Abstract
A steering head has a body and an auger extending through the body. An outer surface of the steering head may have a rear portion that does not extend beyond a maximum perimeter of the exterior of a forward portion. An outer surface of the steering head may have openings that receive respective steering flaps. The steering head may have cutting bits that pivot between extracted and retracted positions in response to the auger's rotation. The auger may have a helical blade that contacts an internal surface of the body. The steering head may have three light elements that emit light visible at the rear of the steering head.
Claims
1. A steering head comprising: an auger; a cutting bit; and a body having an exterior surface extending from a forward end of the body to a rear end of the body, the body defining an interior volume between the forward end and the rear end, the auger being positioned in the interior volume so that the auger is rotatable within the volume about an axis that extends through the forward end and the rear end, and wherein the cutting bit is disposed at least partially forward of the forward end of the body and is attached to the auger, wherein a first part of the exterior surface defines a first maximum perimeter of the exterior surface about the axis between the forward end and a position rearward of the forward end, and a second part of the exterior surface defines a second maximum perimeter about the axis between the position and the rear end of the body that does not extend beyond the first maximum perimeter radially with respect to the axis, wherein the second part defines a portion thereof extending from the rear end of the body to the position that is radially inward of the first maximum perimeter with respect to the axis.
2. The steering head of claim 1, wherein the first part of the exterior surface is generally cylindrical, the second part of the exterior surface is generally cylindrical, and the generally cylindrical first part of the exterior surface has a general diameter perpendicular to the axis that is greater than a general diameter of the generally cylindrical second part of the exterior surface perpendicular to the axis.
3. The steering head of claim 1, further comprising a cover mounted on the portion of the second part of the exterior surface, the cover enclosing a space between the cover and the portion in which is disposed at least one conduit extending from the rear end of the body to the position.
4. The steering head of claim 3, wherein neither the second part of the exterior surface nor the cover extends outward of the first maximum perimeter radially with respect to the axis.
5. The steering head of claim 3, wherein the at least one conduit is a fluid conduit and the cover defines a fluid outlet to an exterior of the cover that is in fluid communication with the at least one conduit.
6. A steering head comprising: an auger; a cutting bit; a body comprising an interior body having an exterior body surface extending from a forward end of the interior body to a rear end of the interior body, the interior body defining an interior volume between the forward end and the rear end, the auger being positioned in the interior volume so that the auger is rotatable within the volume about an axis that extends through the forward end and the rear end, and wherein the cutting bit is disposed at least partially forward of the forward end of the interior body and is attached to the auger, and an outer tube assembly mounted on and outward of the interior body with respect to the axis, comprising a first outer tube having a first inner side and a first outer side, wherein the first outer side is outward of the first inner side with respect to the axis, the first outer tube having a forward end and a rearward end, and the first outer side defining a first maximum perimeter about the axis between the forward end of the first outer tube and the rearward end of the first outer tube, and a second outer tube mounted on the body rearward of the first outer tube and having a second inner side and a second outer side, wherein the second outer side is outward of the second inner side with respect to the axis, the second outer tube having a forward end and a rearward end, and the second outer side defining a second maximum perimeter about the axis between the forward end of the second outer tube and the rearward end of the second outer tube that does not extend beyond the first maximum perimeter radially with respect to the axis, wherein the second outer side defines a portion thereof extending from the rearward end of the second outer tube to the forward end of the second outer tube that is radially inward of the first maximum perimeter with respect to the axis.
7. The steering head of claim 6, wherein the first outer side is generally cylindrical, the second outer side is generally cylindrical, and the generally cylindrical first outer side has a general diameter perpendicular to the axis that is greater than a general diameter of the generally cylindrical second external side perpendicular to the axis.
8. The steering head of claim 7, wherein a center axis of the generally cylindrical first outer surface is parallel to a center axis of the generally cylindrical second outer surface.
9. The steering head of claim 8, wherein the center axis of the generally cylindrical first outer surface is offset from the center axis of the generally cylindrical second outer surface.
10. The steering head of claim 6, further comprising a cover mounted on the portion of the second outer side of the second outer tube, the cover enclosing a space between the cover and the second outer side in which is disposed at least one conduit extending from the rearward end of the second outer tube to the forward end of the second outer tube.
11. The steering head of claim 10, wherein neither the second outer side nor the cover extends outward of the first maximum perimeter radially with respect to the axis.
12. The steering head of claim 10, wherein the at least one conduit is a fluid conduit and the cover defines a fluid outlet to an exterior of the cover that is in fluid communication with the at least one conduit.
13. The steering head of claim 6, further comprising one or more steering flaps disposed on the outer tube assembly and having a distal end, a first flap face facing radially inwardly toward the body surface and an opposing second flap face facing radially outwardly away from the axis, the one or more steering flaps being moveable between an extended position and a retracted position.
14. A steering head comprising: an auger; a cutting bit; a body having an exterior surface extending from a forward end of the body to a rear end of the body, the body defining an interior volume between the forward end and the rear end, the auger being positioned in the interior volume so that the auger is rotatable within the volume about an axis that extends through the forward end and the rear end, and wherein the cutting bit is disposed at least partially forward of the forward end of the body and is attached to the auger, wherein the body defines one or more openings extending inward from the exterior surface toward the axis; one or more steering flaps respectively disposed in the one or more openings, each steering flap having a distal end, a first flap face facing radially inwardly toward the axis and an opposing second flap face facing radially outwardly away from the axis, each of the one or more steering flaps being moveable between an extended position in which the distal end extends away from the axis and a retracted position in which the steering flap, including its distal end, is received in its said opening; and one or more hinges, each hinge connected to the exterior surface and the second flap face of a respective steering flap of the one or more steering flaps to thereby permit pivotal movement of the steering flap between the extended position and the retracted position, wherein the hinge is received in an opening in the exterior surface and an opening in the second flap face of the respective steering flap so that the hinge does not extend outward of the exterior surface, and does not extend outward of the second flap face of the respective steering flap, with respect to the axis.
15. The steering head of claim 14, wherein the body comprises an interior body having an exterior body surface extending from a forward end of the interior body to a rear end of the interior body, the interior body defining the interior volume, and an outer tube assembly mounted on and outward of the interior body with respect to the axis, the outer tube assembly defining the exterior surface.
16. The steering head of claim 15, wherein the outer tube assembly comprises a first outer tube having a first inner side and a first outer side, the first outer side being outward of the first inner side with respect to the axis and the first outer tube having a forward end and a rearward end, and wherein first outer tube defines the one or more openings.
17. The steering head of claim 14, wherein each opening of the one or more openings has a depth so that the steering flap received in the opening, in its said retracted position, does not extend outward of the exterior surface with respect to the axis.
18. The steering head of claim 17, wherein each of the one or more steering flaps is biased towards the retracted position.
19. The steering head of claim 18, further comprising one or more hydraulic cylinders, wherein each hydraulic cylinder of the one or more hydraulic cylinders is disposed operatively between the body and a respective steering flap of the one or more steering flaps, the one or more hydraulic cylinders biasing the one or more steering flaps toward the retracted position.
20. The steering head of claim 14, wherein only one hinge is used to attach each steering flap of the one or more steering flaps to the body.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended drawings, in which:
[0014] FIG. 1 is a schematic illustration of a steering head attached to an auger machine so that the steering head extracts material where one steering flap of the steering head is in an extended position and another steering flap is in a retracted position, in accordance with an embodiment of the present invention;
[0015] FIG. 2 is a perspective view of a steering head as in FIG. 1, with an alternate cutting head and with a steering flap removed;
[0016] FIG. 3 is a plan view illustrating a steering head as in FIGS. 1 and 2, where steering flaps are in a retracted position;
[0017] FIG. 4 is a plan view of a steering head as in FIG. 1, with an exterior thereof transparently presented;
[0018] FIG. 5 is a top view of the steering head as in FIG. 2;
[0019] FIG. 6 is a side view illustrating a steering head as in FIG. 1 or 2, without a cutting head and with steering flaps in a retracted position;
[0020] FIG. 7 is a rear perspective view illustrating the steering head of FIGS. 1-3, illustrating a rear end of an initial auger section and a conduit cover;
[0021] FIG. 8 is a perspective view illustrating a fluid fitting extending into a fluid chamber positioned on a cover of the steering head of FIGS. 1-3;
[0022] FIG. 9 is a top view, toward the rear, of the steering head s in FIG. 2;
[0023] FIG. 10 is a perspective view illustrating a partially opened hinged cover on the top of a second outer tube of a steering head as in FIGS. 1-3, showing a fluid fitting extending into a fluid chamber positioned on the cover and an exterior fluid outlet in fluid communication with the interior of the chamber;
[0024] FIG. 11 is a front perspective view illustrating the steering head of FIG. 3;
[0025] FIG. 12 is a perspective view illustrating a hydraulic cylinder that may be utilized within a steering head, in accordance with an embodiment of the present invention;
[0026] FIG. 13 is a schematic view illustrating the hydraulic cylinder of FIG. 12 positioned within a flap recess, in accordance with an embodiment of the present invention;
[0027] FIG. 14 is a perspective view illustrating an auger section, in accordance with an embodiment of the present invention;
[0028] FIG. 15 is a top view, toward the front, of the steering head as in FIG. 2;
[0029] FIG. 16 is a top view, toward the front, of the steering head as in FIG. 2;
[0030] FIG. 17 is a perspective view illustrating two extraction tube sections that are attached together, with auger sections positioned inside the extraction tube sections, for use with steering heads as illustrated in FIGS. 1-3;
[0031] FIG. 18 is a partial plan view of the two extraction tube sections as in FIG. 17;
[0032] FIG. 19 is a perspective view illustrating light elements facing rearward into a void between the auger blade edge and the inner surface of the second outer tube of the steering heads as in FIGS. 1-3;
[0033] FIG. 20 is a top schematic view of an example assembly of light elements as in FIG. 19;
[0034] FIG. 21 is a perspective schematic view of an example assembly of light elements as in FIG. 19;
[0035] FIG. 22 is a side schematic view of an example assembly of light elements as in FIG. 19;
[0036] FIG. 23 is a perspective view illustrating a cutting head, for use in steering heads as in FIGS. 1-3, comprising a central body and cutting bits pivotably attached to the central body, in accordance with an embodiment of the present invention;
[0037] FIG. 24 is a partial disassembled view of the cutting head as in FIG. 23;
[0038] FIG. 25 is a front perspective view illustrating a cutting head as in FIG. 19 attached on a steering head as in FIGS. 1-3;
[0039] FIG. 26 is a schematic view illustrating a cutting head with cutting bits pivoted to a retracted state so that the cutting head may be moved through the internal volume of the body, in accordance with an embodiment of the present invention;
[0040] FIG. 27 is a schematic view illustrating the cutting head of FIG. 26 with cutting bits pivoted to an extended state so that the cutting head has a greater cutting area, in accordance with an embodiment of the present invention;
[0041] FIG. 28 is a perspective view illustrating an example cutting bit that may be used with steering heads as in FIGS. 1-3;
[0042] FIG. 29 is a perspective, schematic view illustrating a cutting head, for use in steering heads as in FIGS. 1-3, in an open state, in accordance with an embodiment of the present invention;
[0043] FIG. 30 is a plan view of the cutting head as in FIG. 29;
[0044] FIG. 31 is a perspective, schematic view illustrating a cutting head, for use in steering heads as in FIGS. 1-3, in a closed state, in accordance with an embodiment of the present invention;
[0045] FIG. 32 is a plan view of the cutting head as in FIG. 31;
[0046] FIG. 33 is an example block diagram showing various components of a system comprising a steering head, in accordance with an embodiment of the present invention;
[0047] FIG. 34 is a flow chart illustrating an example method for assembling additional augers to existing augers, in accordance with an embodiment of the present invention; and
[0048] FIG. 35 is a top view, toward the front, of the steering head as in FIG. 2, illustrating a steering flap in a deployed state.
[0049] Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention according to the disclosure.
DETAILED DESCRIPTION
[0050] Reference will now be made in detail to presently preferred embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation, not limitation, of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations may be made in the present invention without departing from the scope and spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents. All values indicated below are intended to be approximated values.
[0051] It should be understood that terms of orientation, e.g., forward, rear or rearward, upper, lower, and similar terms as used herein are intended to refer to relative orientation of components of the devices described herein with respect to each other under an assumption of a consistent point of reference but do not require any specific orientation of the overall system. Thus, for example, the discussion herein may refer to the forward, rearward, lateral, side, or similar descriptions, referring to areas of or directions with respect to an auger boring steering head. Such terms may be used in the present disclosure and claims and will be understood to refer to a relative orientation but not to an orientation of a claimed device with respect to an external frame of reference.
[0052] Further, the term or as used in this application and the appended claims is intended to mean an inclusive or rather than an exclusive or. That is, unless specified otherwise, or clear from the context, the phrase X employs A or B is intended to mean any of the natural inclusive permutations. That is, the phrase X employs A or B is satisfied by any of the following instances: X employs A; X employs B; or X employs both A and B. In addition, the articles a and an as used in this application and the appended claims should generally be construed to mean one or more unless specified otherwise or clear from the context to be directed to a singular form. Throughout the specification and claims, the following terms take at least the meanings explicitly associated herein, unless the context dictates otherwise. The meanings identified below do not necessarily limit the terms, but merely provide illustrative examples for the terms. The meaning of a, an, and the may include plural references, and the meaning of in may include in and on. The phrase in one embodiment, as used herein does not necessarily refer to the same embodiment, although it may. The phrase at least one of A and B is satisfied by any of A alone, B alone, A and B alone, and A and B with others. The phrase one of A and B is satisfied by A, whether or not also in the presence of B, and by B, whether or not also in the presence of A.
[0053] Various aspects or features will be presented in terms of systems that may include a number of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. A combination of these approaches may also be used.
[0054] FIG. 1 is a schematic, sectional plan view of a steering head 10 attached to an auger machine 11 so that steering head 10 may extract material 107 from the ground. Steering head 10 comprises an auger 112 and a cutting head 176 with one or more cutting bits positioned on cutting head 176. An auger machine 11 is, in one or more embodiments, configured to generate rotational motion of auger 112 and cutting head 176 so that one or more cutting bits on cutting head 176 are rotated about a center axis of rotation of auger 112. Steering head 10 may be configured to extract material 107 such as rock in some embodiments, in that the hardness of the cutting bits, the strength of the bits and the components delivering force to those bits, the strength of that force, and the strength of the steering head body are collectively sufficient for that task, but steering head 10 may be configured to extract other materials in other embodiments. Steering head 10 may be configured to cut and extract material 107 having high compressive strengths above around 6,000 PSI, above around 6,500 PSI, above around 7,000 PSI, or above around 7,500 PSI, and in one or more embodiments up to around 30,000 PSI. As should be understood, compressive strength of an excavated material may be defined by a standard such as an American Society for Testing and Materials (ASTM) standard. For example, compressive strength may be measured by applying an ASTM C170 standard, which provides a standard test method for compressive strength of stone having varying dimensions, e.g. layered or having other distinguishable geometric features. The design of steering head 10 and other steering heads described herein may enable these steering heads to push through materials having compressive strengths higher than about 7500 PSI, e.g. solid granite, formations of which can have compressive strengths around 25,000 PSI.
[0055] As will be apparent from the present disclosure, steering head 10 may be utilized with any of various suitable cutting heads, examples of which are illustrated throughout the Figures herein. Thus, it should be understood that the illustration of a given cutting head example in the Figures is not intended to limit any of the illustrated embodiments to such a cutting head but, rather, to emphasize that such embodiments are not limited to particular such arrangements. Generally, each of cutting head 176 and the body of the steering head is made of steel. In one or more embodiments and also referring to FIG. 2, the steering head is assembled to minimize or eliminate the extension of components, other than the cutting bits needed to cut the bore and deployed steering flaps needed to steer the steering head, radially beyond the maximum perimeter defined by the steering head, in this instance by the steering head's body, for example by the body's structural body tubing. In one or more embodiments as discussed herein, for example, The body structure of steering head 10 has a first outer tube 71 of approximately inch thick steel positioned proximate to a forward end of steering head 10 and that, alone or in conjunction with body structures attached to it, such as a front ring 44 described below, defines the set of points that are radially outermost from an axis 16 about which auger 112 rotates (and that is coextensive with a center axis of generally cylindrical tube 71/interior body 23 when the auger is in its ideal alignment, as discussed below) and that thereby define an outermost perimeter of tube 71, regardless whether the points within the set of points are at the same or different positions longitudinally on axis 16 (assuming alignment of axis 16 with the tube/body center axis). In the illustrated embodiments, this outermost steering head perimeter is defined by a steel ring 44 welded onto the forward end of the cylindrical main body portion of tube 71. Steering head 10, in one or more embodiments, includes a plurality of steering flaps 50 (one of which is removed from the steering head as shown at FIG. 2) that may be retracted to an undeployed disposition, in which the outer surfaces of the steering flaps generally conform to the outer surface of tubing 71 so that the flaps do not materially divert the steering head's movement from a direction away from auger machine 11 along a straight axis (e.g. horizontal), or extracted to a deployed position further from a straight axis, in which one or more of the flaps exert pressure onto the wall of the bore being cut by the steering head, thereby urging the steering head to turn in the ground in the opposite direction and thereby away from the straight axis. In one or more embodiments as described herein, when a flap 50 is in its undeployed position, no portion of the flap or its hinge extends outside the maximum perimeter defined by first outer tube 71, thus reducing the likelihood that the engagement of the bore surface with the flap or its hinge as the steering head moves forward along a straight axis 16 through rock or dirt will damage those components and correspondingly facilitating the steering head's use to bore through material that would likely otherwise cause such damage. For example, each steering flap 50 may be retracted, in its undeployed position, into a respective opening 91 in the body of first outer tube 71, extending radially inward from the exterior surface of first outer tube 71, so that steering flap 50 does not extend beyond the maximum perimeter defined by first outer tube 71. Similarly, each steering flap's hinge 70 is positioned within a respective hinge recess 70A (see also FIG. 3) so that hinges 70 do not extend beyond the maximum perimeter defined by first outer tube 71.
[0056] In one or more embodiments, steering head 10 comprises a body having a generally cylindrical steel interior body 23. Interior body 23 has, in one or more embodiments, an approximately twenty inch diameter exterior body surface 33 extending from a forward end 92 of interior body 23 to a rear or trailing end 94 of approximately 24 inches, defining an interior volume 125 between lead and rear ends 92 and 94 bounded by the body's generally cylindrical steel central portion between the ends. The steel that forms interior body 23 is, in these examples, approximately 0.5 or 0.75 thick in the radial direction. End 92 is a forward end in that it is the lead end when the steering head is in use excavating a bore. Steering head 10 also comprises an auger 112 positioned in interior volume 125 that has a center portion 112A along axis 16 and a helical screw blade 113A extending radially outward from center portion 112A and its axis 16. Steering head 10 comprises a cutting head 176, which may comprise one or more cutting bits thereon. In one or more embodiments, cutting head 176 is attached at an end of auger 112 proximate body lead end 92. Auger 112 is positioned in interior volume 125 so that the auger is rotatable within interior volume 125 about axis 16. Axis 16 (which, ideally, is coextensive with the axis of cylindrical body interior volume 125) extends through body lead end 92 and rear end 94 generally in a dimension 56, horizontally in the perspective of FIG. 1 and perpendicular to a dimension 54, which extends vertically in the perspective of FIG. 1. A helical outer or perimeter edge of helical screw blade 113A defines a distal portion, or in some instances a contact portion, 113B.
[0057] Auger 112 is configured in its dimensions so that contact portion 113B engages the interior wall of interior body 23 surrounding interior volume 125, thereby reducing inaccuracy in the rotation of center portion 112A and correspondingly increasing stability of the position of axis 16 in dimension 56. The fit between contact portion 113B and the interior body 23 interior wall is not a friction fit but is, instead, designed so that, given the dimensional tolerances and movement tolerances of the components in the system, there is sufficient clearance between contact portion 113B and the body interior wall to permit the auger to rotate within the body interior volume but to do so with contact between those structures as the auger rotates during its normal, intended use, as permitted by those tolerances, to bound the auger's motion normal to a straight axis 16 within an intended range. For instance, in one or more embodiments as discussed herein, when the cutting bits of cutting head 176 are disposed at their extended positions, such that the maximally-extended cutting bit(s) define(s) a cutting perimeter in a plane normal to axis 16, the gap between auger blade contact portion 113B and the interior body inner volume surface is chosen so that, throughout the auger's full range of motion perpendicular to the axis of the interior body inner volume, that cutting perimeter always entirely encompasses the maximum perimeter defined by the steering head body, e.g. by the steering head's outer body tubing. In such embodiments, the steering head body's maximum perimeter is coextensive with or is within the cutting perimeter at all angular positions about the body's center axis. Thus, in such embodiments, the gap between auger blade contact portion 113B and the interior body inner volume surface is small enough to maintain that condition true. In embodiments where, as discussed herein, the maximum steering head body perimeter is defined by ring 44, then, to maintain the relationship discussed above, the cutting head is dimensioned so that the extended cutting bits would cut a cutting perimeter that is at least equal to the steering head body diameter (in this example, the diameter of ring 44), plus a two times multiple of the gap between auger blade contact portion 113B and the interior body inner volume surface. In other embodiments, allowance is made for wear of auger blade contact portion 113B (inward, toward axis 16) as the auger blade contacts the interior body inner volume surface. In such embodiments, the cutting head is dimensioned so that the extended cutting bits would cut a cutting perimeter that is at least equal to the steering head body diameter, plus a two times multiple of the gap between auger blade contact portion 113B and the interior body inner volume surface, plus a two times multiple of an expected or permitted wear distance for the auger cutting blade.
[0058] In most instances, the gap between auger blade contact portion 113B and the interior body inner volume surface causes, due to gravity, the auger blade to contact the bottom of the interior body inner volume surface. When the auger is sufficiently loaded, however, the auger blade may contact other portions of the interior body inner volume surface, e.g. at any point entirely about the inner volume surface's perimeter. Because wear on the inner surface of interior body 23 arising from this contact between the auger blade and the interior body is distributed, whereas wear on the auger is concentrated on auger blade contact portion 113B, the auger blade wears more quickly than does steering head inner body. In one or more embodiments, the width of auger blade contact portion 113B (in the dimension parallel to auger axis 16) is greater than the width of that portion of the auger blade radially inward of the edge. Such increased thickness in the auger blade edge, in such embodiments, is present in the section of auger disposed within the steering head, or at least disposed within interior body 23, but not in auger sections rearward of the steering head, in embodiments in which the auger blade is not sized to make contact with the inner diameter of pipe casing sections or extraction tube sections. In other embodiments, the auger blade edge is thickened in all auger sections.
[0059] Generally cylindrical first outer tube 71 is, in one or more embodiments, part of the body's outer tube assembly 71A positioned radially outward of interior body 23 relative to axis 16 and the body axis so that tube assembly 71A surrounds interior body 23. As noted, in one or more embodiments, first outer tube 71 has a generally cylindrical inner surface 69C and a generally cylindrical external surface 69A. Inner surface 69C faces exterior body surface 33 of interior body 23 so that inner surface 69C of first outer tube 71 and outer surface 33 of generally cylindrical interior body 23 are concentric about the body axis (16, assuming the auger axis is coextensive with the body axis). It should be understood that first outer tube 71, in one or more embodiments, is not necessarily coextensive with interior body 23 over their lengths along axis 16, though in one or more other embodiments, it is. Thus, for example, interior body 23 may be shorter in such length than first outer tube 71 or vice versa. First outer tube 71 has a forward end proximate lead end 92 of interior body 23 and a rearward end located proximate the body's rear end 94, with a rear edge radially outward of the edge of rear end 94. Steel front ring 44 is welded to the forward end of tube 71. In one or more embodiments, first outer tube 71 is mounted on interior body 23 by a plurality of elongated generally rectangular steel plates 39 (see also FIGS. 4 and 5) that extend, in their dimensions of elongation, generally parallel to the body axis. Each plate 39 is generally planar and is welded to outer surface 33 of interior body 23 so that the plates extend radially outward from body outer surface 33 to inner surface 69C of first outer tube 71, to which they are also welded, in planes that include, and that are angularly spaced apart from one another about, the body axis. As shown in FIG. 5, the leftmost and rightmost plates 39 (in the perspective of FIG. 5) extend continuously between a front end (closest to body front end 92) and a back end (closest to body rear end 94) of the plate. There are two other such continuous plates on the opposite side of interior body 23. Between each adjacent pair of continuous plates 39 are two parallel plates 39 that are discontinuous in their centers, to allow the disposition of fluid conduits and hydraulic cylinders, as discussed below, so that each of those plates is comprised of a front plate section 39A and a rear plate section 39B. Just as their continuous counterparts, however, the discontinuous plates are welded to and extend between the outer surface of interior body 23 and the inner surface of outer tube 71 so that all of plates 39 support first outer tube 71 in its position with respect to interior body 23. As indicated in FIG. 4, plate sections 39A and 39B also provide support for flaps 50. When a flap 50 is deployed to its extended position by one or more corresponding hydraulic cylinders, the flap pushes the steering head in the opposing direction, which can thereby cause the bore surface to apply pressure to the exterior surface of the flap 50 180 opposite the flap 50 being deployed.
[0060] FIG. 4 illustrates an embodiment of a steering head 10, with the body of outer tube assembly 71A and a flap thereof being transparent so that the steering head assembly inside the outer tube assembly is visible. In this embodiment, at front and rear ends 92 and 94 of interior body 23, respective steel annular rings 41 and 43 are welded to outer surface 33 of interior body 23 and inner surface 69C of first outer tube 71, thereby also (similarly to plates 39) locating first outer tube 71 with respect to interior body 23 and protecting the volume between interior body 23 and first outer tube 71 from ingress of earth and rock that otherwise passes through an interior volume of interior body 23 after being dislodged by cutting head 176, by the action of auger 112, and protect the interior volume between interior body 23 and first outer tube 71 from ingress of bentonite. Annular rings 41 and 43 also reinforce interior body 23.
[0061] The wall thicknesses of both interior body 23 and first outer tube 71 are generally constant about both structures, such that first external surface 69A and the inner diameter surface of interior body 23 are also generally cylindrical and concentric about the body axis. At each angular position of radii extending perpendicularly outward from the body axis (which, for purposes of discussion, is coextensive with auger axis 16), along the length of axis 16 between the first outer tube's forward end and its rearward end, the greatest length of the radii at that angular position is part of the maximum perimeter about axis 16 defined by first outer tube 71 (the first maximum perimeter). The remainder of that first maximum perimeter is defined by the greatest radial lengths at positions on axis 16 between the first outer tube's forward and rearward ends for the remaining angular positions about axis 16. As discussed above, in one or more embodiments, the first maximum perimeter is defined by front ring 44.
[0062] A steel frustoconical front shield 46 extends between the forward end of interior body 23 and the forward end of first outer tube 71 and is welded to each. Shield 46 guides earth and rock debris cut from the bore face by cutting head 176 radially inward toward the auger, which, in turn, moves the debris rearward through the interior volume 125 of interior body 23. A through hole 36 extends through the frustoconical wall of shield 46 to allow flow of water from the output of a rigid water conduit 24, as discussed below.
[0063] The outer tube assembly also comprises a generally cylindrical second outer tube 73 that is rearward (with respect to the steering head's direction of travel, along dimension 56 and axis 16) of first outer tube 71 and interior body 23. Second outer tube 73 has a generally cylindrical second inner surface 69D and a generally cylindrical second external surface 69B. The second outer tube's forward end is adjacent the rearward end of first outer tube 71 and rear end 94 of interior body 23 and is attached to the first outer tube through weldment to steel rear annular ring 43 and, e.g. at the bottom of the steering head, to first outer tube 71. Through such connection, for example, the second outer tube is mounted to interior body 23. Whereas the generally cylindrical outer surface 69A of first outer tube 71 has a general cross-sectional diameter of approximately 26 inches, the generally cylindrical outer surface 69B of second outer tube 73 has a general cross-sectional diameter of approximately 24 inches. The generally circular cross section of outer surface 69B of second outer tube 73 is centered about an axis that is slightly below the axis of interior body 23 and first outer tube 71 (which in this example is coextensive with axis 16), and the generally circular cross sections of the outer surfaces of outer tubes 71 and 73 are at the same radial distance from axis 16 only at the bottom of the steering head (assuming the steering head is in its operative position, as indicated in FIG. 1), directly below axis 16. Thus, the outer surface of second outer tube 73 is aligned with the outer surface of first outer tube 71 at the bottom of the steering head but is increasingly offset radially inwardly from the outer surface of the first outer tube at higher positions on the steering head, reaching the greatest offset at the steering head top. At each angular position of radii extending perpendicularly outward from the interior body axis (in this example, axis 16), along the length of axis 16 between the second outer tube's forward end and its rearward end, the greatest length of the radii at that angular position is part of the maximum perimeter defined by second outer tube 73 about the interior body axis (the second maximum perimeter). The remainder of that maximum perimeter is defined by the greatest radial lengths at positions on the interior body axis between the second outer tube's forward and rearward ends for the remaining angular positions about that axis. While it should be understood that the geometries of the first and second outer tubes' outer surfaces can vary, in one or more embodiments the second maximum perimeter does not extend, radially outward with respect to the interior body axis, beyond the first maximum perimeter at any angular position about that axis.
[0064] More generally, in one or more embodiments, second external surface 69B defines at least a portion thereof extending (generally parallel to the interior body axis and at a given angular position about that axis, e.g. at the top of second outer tube 73) continuously from the rearward end of second outer tube 73 to the forward end of second outer tube 73 that is radially inward of the first maximum perimeter with respect to the axis of the interior body and the first outer tube. For example, at the upper portions of steering head 10, second external surface 69B is radially inward (with respect to the interior body/first outer tube axis) of the first maximum perimeter defined by first outer tube 71 (at the uppermost surface of second outer tube 73, by approximately two inches), but second external surface 69B is more proximate to the first maximum perimeter defined by first outer tube 71 at lower portions of steering head 10, and the first and second maximum perimeters coincide at the bottom of the steering head. In some embodiments, such as discussed above with respect to FIG. 1, first external surface 69A of first outer tube 71 and second external surface 69B of second outer tube 73 may both be generally cylindrical in shape, and the generally cylindrical first external surface 69A may have a general diameter D1 perpendicular to axis 16 that is greater than a general diameter D2 of the generally cylindrical second external surface 69B of second outer tube 73, perpendicular to the interior body/first outer tube axis (in the Figures, coinciding with auger axis 16). As shown in FIG. 6, the presently described embodiment of second external surface 69B generally extends along, and is centered about, an axis 16B that is parallel to and offset from axis 16 by about an inch, as indicated at 01. In one or more embodiments as described herein, one or more components, e.g., electrical and fluid (e.g., water, hydraulic, and lubricant) conduits, are disposed on an outer surface of second outer tube 73 that is radially inward of the first maximum perimeter defined by first outer tube 71. The positioning of such components, and for instance all components external to the steering head's outer tubes susceptible to damage from engagement with the bore surface, within the first maximum perimeter defined by first outer tube 71, facilitates use of steering head 10 to cut and extract materials having high compressive strengths without the wall of the bore engaging and damaging the components.
[0065] A steel half-frustoconical rear shield 49 extends between the rear end of interior body 23 and the forward end of second outer tube 73 and is welded to each. Shield 49 extends over the bottom 180 of the rear opening of interior body 23 and the interior of second outer tube 73 and guides the cutting head and auger, which will have a tendency to pull down with gravity to the bottom of second outer tube 73, up into interior 125 of interior body 23 when the cutting head and auger are inserted into the steering head, as discussed below. At the two top edges of half-frustoconical rear shield 49, steel transition flanges 49A and 49B are welded to the rear edge of interior body 23, the interior surface of second outer tube 73, and the top edge of half-frustoconical rear shield 49.
[0066] Also, as noted above, the radially outermost component of steering head 10 is steel ring 44. Its outermost circumference is approximately the same diameter, or of a lesser diameter, as the cutting diameter of cutting head 176. In one or more embodiments, the ring 44 diameter is about greater than the maximum perimeter of first outer ring 71, to facilitate the steering head's passage through the bore, and in such embodiments an operator may deploy one or more of the steering flaps during the steering head's movement in order to maintain the steering head on a desired line of travel. Thus, ring 44 fits approximately flush or otherwise closely in the bore, inhibiting the steering head from undesirably moving radially in the bore. Further, the gap between the forward ring's outer circumference and outer surface 69A of the main generally cylindrical body of first outer tube 71 allows a small degree of movement (in one or more embodiments, about 5 of pivot about its hinge axis) of steering flaps (discussed below) disposed in first outer tube 71 so that the steering flaps can deploy outward to engage the bore. Being disposed at the front of first outer tube 71, proximate the cutting head, ring 44 allows the steering head to pivot slightly on the ring's outer circumference when a flap deploys.
[0067] It should be understood in view of the present disclosure that the configuration, including geometries, of load-bearing body structure of steering head 10 may vary. For example, in embodiments discussed above, in which the overall body system comprises a generally cylindrical inner body with a generally cylindrical outer body structure radially outward of the inner structure, so that multiple steering head components may be housed between the inner and outer structures, it should be understood that the inner and outer structures may, in one or more embodiments, be formed from a single, at least initially monolithic steel cylinder, which is then machined to define the inner and outer structures and the several voids therein that may be provided to accommodate electrical and fluid conduits.
[0068] Steering head 10 comprises a plurality (in this instance, four) of directional steering flaps 50 pivotally attached to first outer tube 71 by hinges 70. Each hinge 70 is a rectangular piece of spring steel that is sufficiently flexible to allow flaps 50 to pivot about a flex at the rectangular flap's center by at least, in one or more embodiments approximately 5 in response to a hydraulic or pneumatic piston, as discussed below. Referring also to FIGS. 15 and 16, each flap 50 is received in a through hole 91 extending through first outer tube 71. The major portion of a through hole 91 is shaped just larger than the perimeter of its flap 50 so that, when the flap is received in the through hole 91 in the flap's retracted position, the flap's outer surface is even with, and generally conforms to the curvature of, the cylindrical outer surface of the main body of first outer tube 71. Through hole 91 also includes a smaller, generally rectangular, section extending forward of the through hole's main portion, to receive the forward half of flap hinge 70. A correspondingly generally rectangular steel flange 45 is welded to the bottom portions of the boundaries of the smaller through hole section, thereby defining a recessed portion of outer surface 69A of first outer tube 71. The first side of each rectangular hinge 70 is connected at a respective such recessed portion of first external side 69A by four bolts passing through the hinge and its corresponding plate 45, while the second side of each hinge 70 is connected at a similar depression in the outer surface of the hinge's steering flap 50 by another four through-bolts. Hinges 70 thereby permit pivotal movement of steering flaps 50 between extended position (indicated at 64) and retracted position (indicated at 62). When one of the flaps is deployed to its extended position 64, the flap engages the wall of the bore through which the steering head moves. The pressure the flap exerts against the bore wall tends to divert the steering head's forward movement off of its straight path, in a direction away from the flap. In the illustrated embodiments, there are four steering flaps, spaced apart from each other at 90 intervals about the outer surface of first outer tube 71, but it should be understood that more or fewer spaced apart steering flaps may be used. Referring also to FIG. 35, each flap 50, in one or more embodiments, has respective depending side portions 167 that extend from the two side edges of the main portion of flap 50 (that generally conforms to the geometry of outer surface 69A of first outer tube 71) radially inward (when the flap is in its retracted position) toward the interior body's axis. In one or more embodiments, the distal edges of side portions 167 extend to and engage outer surface 69A when the flap is in its retracted position, thereby supporting the flap in maintaining its continuity with outer surface 69A. Side portions 167 also tend to block ingress of rock and earthen debris into the volume between the interior body and first outer tube 71. As also illustrated in FIG. 4, a plurality of angled support members 42 are welded to and extend between side portions 167 and the main, upper portion of flap 50.
[0069] Hinges 70 may be attached to first outer tube 71 and flaps 50 in various ways. In one or more embodiments, for example and as described above, the forward side of each hinge 70 is received in a hinge opening 70A (see FIG. 3) in first external surface 69A, and the second side of each hinge 70 is received in a hinge opening 70A (see FIG. 3) in second flap face 79B of a steering flap 50. Openings, in this instance recesses rather than through-openings, 70A and 70A are as deep or deeper (in the radial direction from axis 16) than the thickness of the hinge, so that the hinges are received entirely within the recesses. Thus, when steering flaps 50 are in retracted positions 62, hinges 70 do not extend radially outward of first external side 69A of first outer tube 71 with respect to the interior body axis (coextensive, for purposes of discussion, with axis 16) (or, thus, outward of the outer circumference of front ring 44) and do not extend outward of the outer faces of steering flaps 50 with respect to the interior body axis (see 16). Thus, the bore wall generally does not engage the hinges as the steering head moves through the earth. Limiting the number of components that extend radially outwardly relative to first outer tube 71 limits the amount of force acting on steering head 10 at areas away from cutting head 176, allowing steering head 10 to operate more efficiently.
[0070] In one or more embodiments, the steering head includes four hydraulic cylinders 128, respectively disposed in the four flap through holes 91 that respectively receive the four steering flaps 50, that move steering flaps 50 between their retracted position 62 and extended position 64. Each hydraulic cylinder 128 is attached at its rod end or tube end to the outer surface 33 of interior body 23 and, at the other of its rod end or tube end, engages or is attached to first flap face 79A, which faces radially inwardly toward interior body 23. The ports are attached to hydraulic fluid lines that pass through a cover on second outer tube 73 and are driven by a hydraulic pump, as discussed below. Through the pump's operation, hydraulic cylinders 128 are moved between a retracted state and an extended state to correspondingly drive steering flaps 50 between retracted position 62 and extended position 64. In one or more embodiments, each hydraulic cylinder is a single acting cylinder in that the flap 50 which the cylinder 128 controls is biased by its hinge 70 to its retracted position. Thus, when the hydraulic pump, discussed below, pushes hydraulic fluid into the cylinder through the single hydraulic fluid line to cause the cylinder to expand and raise the flap, it does so against a bias resistance applied by the flap due to the flap's hinge 70. If the control system deactivates the hydraulic fluid pressure applied by the pump, the hinge/flap bias tends to push cylinder 128 back to its retracted position, allowing the flap 50 to return to its retracted position. As will be understood, this moves the hydraulic fluid from cylinder 128 back up the hydraulic line toward the pump and the hydraulic fluid reservoir.
[0071] In the embodiment illustrated in FIG. 2, there is one hydraulic cylinder 128 per flap 50. In the embodiment illustrated in FIG. 4, however, there are two hydraulic cylinders per flap. As should be understood in view of the present disclosure, the size of the steering head body, and correspondingly of the steering flaps, may vary. For larger flaps, and depending on the strength of the hydraulic cylinders, more than one hydraulic cylinder may be needed to deploy each flap. It should be understood that the arrangements illustrated in FIGS. 2 and 4 are for purposes of example only.
[0072] In one or more embodiments, only one, large, monolithic hinge 70 is used to attach each steering flap 50 to first external side 69A of first outer tube 71. As apparent in the Figure, the hinge is aligned with a center line that would bisect the flap through a plane that includes the steering head interior body axis and that would also bisect the hinge. Minimizing the number of hinges on the steering flap 50 minimizes the amount of resistance generated by the engagement of steering head 10 with the bore wall as steering head 10 is urged through underground material 107.
[0073] Each steering flap 50 extends between a hinge end 68 and a distal end 66. Steering flaps 50, and other steering flaps as described herein, are comprised of steel or other suitable material. Hinge end 68 of each steering flap 50 is pivotably attached to first outer tube 71 via a respective hinge 70. Steering flaps 50 are fully received in through holes 91 in first outer tube 71 when steering flaps 50 are in retracted position 62, and the outer surface of each flap 50 may conform to the generally cylindrical outer surface of first outer tube 71. Hinges 70 are disposed with respect to their flaps and first outer tube 71 so that when steering flaps 50 are received in flap through holes 91, no portion of a steering flap 50 extends radially outwardly of the maximum outer perimeter defined by first outer tube 71. In one or more embodiments, the outer surfaces of the flaps are radially within the first outer tube's maximum outer perimeter as defined by front ring 44. As such, when steering head 10 is urged through underground material 107 (e.g., to the left along dimension 56), resistance between the flaps and the bore surface is reduced when the flaps are in retracted position 62 as compared to resistance that might exist if the steering flaps were proud of the generally cylindrical outer surface of first outer tube 71 or of ring 44.
[0074] When steering flaps 50 are each retained in a retracted position 62, or are selectively deployed to maintain the steering head on line, steering head 10 generally maintains its direction (to the left in FIG. 1) as auger machine 11 continues to push the steering head (indirectly, through pushing casing or extraction tube sections attached to the steering head, as discussed below) and auger 112 in that direction. However, the operator of auger machine 11 may utilize the auger machine's control system to actuate one or more hydraulic pumps to, in turn, deploy one or more of steering flaps 50 to their extended positions 64 to adjust the steering head's direction. For example, with the bottom steering flap in an extended position 64 and with the top steering flap in a retracted position, the cutting path for steering head 10 may turn upward (in the perspective of FIG. 1), with the new cutting path extending upwardly and to the left relative to the forward direction defined by axis 16 as it is shown in FIG. 1. Often, the steering flaps are deployed when, for example due to variances in the earth or rock through which the steering head is moving, the steering head deviates from its intended path. In such instances, the steering flaps are deployed in order to keep the steering head on a straight path. In steering head 10, only two steering flaps 50 are visible, but as noted above and with regard to steering head 10 of FIG. 2A, the steering heads of one or more embodiments as discussed herein includes four steering flaps 50, each angularly offset 90 from the two adjacent flaps and 180 from the remaining flap. In other embodiments, more or fewer than four flaps may be employed. In some embodiments, more than one steering flap may be moved to an extended position at one time to cause a steering head to move in a desired direction. Furthermore, steering flaps 50 may be extended in varying amounts to obtain the desired direction. By extending more than one steering flap at once and/or by extending steering flaps in varying amounts, steering head 10 may be adjusted to extend in effectively any direction. In some embodiments, steering flaps 50 may be extended so that distal ends 66 extend radially outwardly by a distance of about 2 inches or more, but steering flaps 50 may extend in different amounts in other embodiments.
[0075] FIG. 1 also illustrates a casing 108. The rear end 94 of steering head 10 may be mounted to a casing 108 by welding. As shown in FIG. 1, casing 108 is also engaged to an auger machine 11, with an auger 112 engaged to and extending from the auger machine 11 through the casing 108 and steering head 10. Auger machine 11 rotates auger 112, thereby enabling auger 112 to perform a boring operation through surrounding material 107. Auger 112 removes material 107 through the steering head 10 and into a starting pit in which auger machine 11 is movably mounted on a track. As the bore hole is lengthened, additional sections of casing 108 may be welded to previously laid casings 108 until a utility crossing line is completed, and additional auger sections therein may be received within casings 108. Once the utility crossing line is completed, auger machine 11, auger 112, and steering head 10 may be removed, and a utility line (e.g. power, water, sewer) may then run through the interconnected casing sections.
[0076] FIG. 3 is a side view illustrating steering head 10 where steering flaps are in their retracted positions. Steering head 10 is an embodiment of a steering head schematically shown in FIG. 1 and should be understood to include components as shown and discussed herein with regard to FIG. 1. Steering head 10 comprises a cutting head 176 that may include one or more cutting bits 209. Cutting bits 209 have cutting portions thereon configured to cut through material. As should be understood, cutting bits of high grade carbide may be used to cut rock up to about 12,000 PSI, while roller cone cutting bits (shown in FIG. 3) may be used for rock up to about 20,000 PSI, and industrial diamond cutters up to about 25,000 PSI, and disc cutters up to about 30,000 PSI. An auger 112 (see FIG. 7) is positioned within interior volume 125 of interior body 23 (see FIG. 1) and within the interior volume defined by second outer tube 73. Auger 112 generally extends along, and is rotatable about, axis 16. A center auger body portion 112A (see FIG. 7) of auger 112 generally extends along axis 16, and axis 16 is generally parallel to dimension 56 (FIG. 3), with both axis 16 and dimension 56 generally extending left to right (and vice versa) in FIG. 3. Axis 16 is generally perpendicular to dimension 54, with dimension 54 generally extending vertically in FIG. 3.
[0077] Steering flaps 50 have distal edges 50B positioned at flap distal end 66 that are rounded in shape to conform to the shape of the bore through which the steering head moves when the steering flap is deployed outward so that the flap's edge 50B engages the bore wall. As indicated herein, the shape of the bore wall is defined, in one or more embodiments, by the maximum cutting diameter of cutting bits 209 of cutting head 176, which will be slightly larger than the maximum perimeter of the steering head body. Thus, if the steering head's cutting head, and corresponding bore wall geometry, are known, the geometry of steering flap rear edge 50B may be determined so that the edge 50B geometry conforms to the bore wall geometry when flap 50 is deployed at the angle (with respect to body of tube 71 axis 16) at which edge 50B engages the bore wall. This conformance between the flap edge and the bore wall optimizes the accuracy of the steering flap's influence on the steering head's direction and reduces the chance that engagement between the steering flap with the bore wall results in damage to the flap. However, distal edges 50B may have different shapes in other embodiments.
[0078] In some embodiments, each spring steel hinge 70 is in a nontensioned state when its flap 50 is in its retracted position 62, so that the hinge biases the flap to that position and so that each steering flap 50 is normally positioned in retracted position 62. Additionally, or alternatively, hydraulic cylinders 128 (see FIG. 1) may be attached to the underside of respective flaps 50 so that the cylinders generally maintain steering flaps 50 in their retracted positions at most times. However, it should be understood that, in other embodiments, steering flaps 50 are not biased, or are biased through a different mechanism.
[0079] Referring to FIGS. 1-4, 7, 17, and 18, several conduits (enclosing, e.g., electrical wiring for communications with controllers disposed within the steering head, wiring for conveying power to electronic components in the steering head, hydraulic lines for hydraulic fluid for steering head hydraulic systems, and/or air lines for pneumatic systems, and water) extend through a series of sequential covers 131 that extend over the upper outer surfaces of casing sections or extraction tubes (described below) from the auger machine pit, or starting pit, to the steering head, and then through a cover 75 over the upper outer surface of second outer tube 73. Each cover 131 and 75 is radially inward of the maximum periphery defined by first outer tube 71, e.g., by front ring 44. In one or more embodiments, cover 75 has a height above the surface of second outer tube 73, and covers 131 have a height above the casings or extraction tubes behind it, in the radial direction outward from the body axis that permits the disposition of the conduits in the volume defined between the exterior surfaces of second outer tube 73 and pipe casings/extraction tube sections and the interior surfaces of covers 131 and cover 75 but that maintains the exteriors of covers 131 and cover 75 within the maximum perimeter defined by first outer tube 71.
[0080] Cover 75, disposed on the top of second outer tube 73, is pivotably attached to second outer tube 73 via a hinge 75A, with cover 75 being positioned proximate to upper (in the perspectives of FIGS. 1-4 and 7) portion 99A (FIG. 3) of second outer tube 73. Referring also to FIG. 7, cover 75 may be pivoted open about hinge 75A to allow access to internal volume 75B of cover 75 and to fluid outlet fitting 77 (FIG. 8). FIGS. 3 and 7 illustrate cover 75 pivoted to its closed position, so that FIGS. 3 and 7 show the outer surface of cover 75, while FIG. 8 illustrates cover 75 pivoted to its open position, so that FIG. 8 shows the inner surface of cover 75. As discussed below, pipe casing sections or extraction tube sections may be sequentially welded or bolted, first, to the rear end of the steering head's second outer tube and, thereafter, to each successive pipe casing section or extraction tube section. As shown in FIGS. 1, 17, and 18, each of these pipe casing sections or extraction tube sections has a respective cover (indicated at 131) hingedly attached to the top thereof, in sequential alignment with the cover 75 on the top of second outer tube 73 and, thereafter, covers 131 on the pipe casing sections, so that the sequence of sequential covers provides a generally continuous enclosure for the conduits as they extend from the auger boring machine's steering head control station 114 to first outer tube 71 of steering head 10. At that point, the conduits pass through a through hole 48 (FIG. 9) in rear steel ring 43 and into the volume between the exterior surface of interior body 23 and the interior surface of first outer tube 71. Within this gap, the conduits are directed to the various components they serve, for example one or more controllers of controller-controlled components, respective hydraulic pistons 128, and water tube 24. Through holes, such as at 57A-E (FIG. 5), through the continuous support plates 39 permit passage of conduits that need to travel to end-components located in other quadrants of the gap.
[0081] In one or more embodiments, the conduits include a communication line 104 and a plurality of fluid supply hoses 105 that extend from the auger boring machine control station into and through the internal volume defined by cover(s) 131 and 75 and the exteriors of the one or more casings/extraction tube sections and second outer tube 73 over which the cover(s) are disposed. Communication line 104, e.g. including a six wire power cable, extends, and establishes electronic communication, between control station 114 and respective controllers of one or more controller-controlled components of steering head 10, passing additionally into the gap between interior body 23 and first outer tube 71. It should be understood that communication line 104 represents, in one or more embodiments, multiple individual wire conduits, providing communication and power to the controllers. In one or more other embodiments, some of these communication lines 104 may be omitted where external control station 114 communicates with the one or more controllers on steering head 10 by wireless communication links, but in these embodiments one or more power buses are present.
[0082] Fluid reservoir(s) 115 is, in one or more embodiments, fluidly connected to conduits such as a fluid supply hose 105, which extends through the internal volume defined between cover 75 and, to the extent present, cover(s) 131 and the exteriors of the casings/extraction tube sections and second outer tube 73 until fluid supply hose(s) 105 reaches and connects to its destination, e.g., a hydraulic piston, a water outlet, or a fluid outlet fitting 77 (see FIG. 8) that fluidly connects to the interior of fluid supply hose(s) 105. In some embodiments, reservoir(s) 115 comprises multiple distinct and independent reservoirs that hold different fluids, such as water to be directed by a fluid hose 105 to the cutting head (via rigid tube 24 and through hole 36 in forward shield 46, as shown in FIG. 4) to cool the cutting head during use, or hydraulic fluid to be directed to the hydraulic cylinders 128 (FIGS. 2 and 4), or bentonite to direct to an outlet of cover 75 for distribution on the bore wall as a lubricant for pipe casings or extraction tubes pushed into the bore behind the steering head. Thus, in such embodiments, hose 105 comprises a plurality of distinct, independent fluid hoses, a separate fluid supply hose being respectively provided for the independent reservoirs 115 for each fluid type. For instance, a fluid supply hose may convey water or other coolant fluid from a water-filled reservoir 115, through the volume defined by cover(s) 75/131 over the exterior of second outer tube 73 and one or more casing sections or extraction tube sections, through annular ring 43, into the gap between interior body 23 and first outer tube 71 to water tube 24 and through hole 36. After cooling the cutting head bits, the water moves rearward, carried by the auger along with rock and earthen debris. As discussed below, some of this water, at the auger blade edge, lubricates the interface between the blade edge and the inner wall of steering head interior body 23.
[0083] In some embodiments, one or more hydraulic fluid hoses 105 extend from a hydraulic fluid reservoir 115, through the internal volume defined by cover(s) 75/131 over the exterior surfaces of second outer tube 73 and one or more bore casings or extraction tubes, to hydraulic cylinders 128 positioned proximate steering flaps 50 in the flaps' respective recesses 91. By selective operation of a pump 147, discussed below, which can select one of a plurality of output hydraulic fluid hoses, the operator can push hydraulic fluid to, or allow withdrawal of hydraulic fluid from, each hydraulic cylinder 128, to thereby extend or retract the cylinder. Through such operation, the operator deploys the cylinder's associated flap 50 outward against the bore wall or retracts its associated flap inward into its recess 91. In such embodiments, the system includes a plurality of discrete, independent hydraulic hoses from the (same) hydraulic fluid reservoir, pumped selectively by the hydraulic pump 147 (FIG. 1) and each leading, as a single line activation system, to a respective hydraulic cylinder 128. Through such selective control of the flaps through their respective cylinders, the operator may control the steering of steering head 10. While a hydraulic cylinder 128 is contemplated to generate movement of steering flaps 50, other mechanisms, such as pneumatic cylinders or water bags that can be selectively filled and drained, may be used.
[0084] In some embodiments, a lubricant fluid hose 105 extends from a lubricant fluid reservoir 115, through the internal volume defined by cover(s) 75/131 over the exterior surfaces of second outer tube 73 and one or more bore casings or extraction tubes, to a fitting 77 (FIG. 8). The system includes a pump 147 to pump lubricant from the reservoir to fitting 77. Fitting 77 extends through a wall on the interior of cover 75 that defines a chamber for receiving a lubricant fluid, such as bentonite, stored in its respective reservoir 115 that is then, as discussed below, output through slits in cover 75 over the exterior of the second outer tube. The fluid coats the rock and earthen bore wall as the steering head moves through the bore, thereby providing a lubricated bore surface for the following casings or extraction tubes. Fitting 77 defines a fluid channel through the fitting, facilitating delivery of the fluid to the chamber for this purpose.
[0085] External control station 114 includes a respective pump, indicated at 147, within the fluid hose line 105 from each of the distinct, independent fluid reservoir 115 that, under the operator's control at control station 114, draws fluid from each reservoir and moves the fluid over the respective hoses 105 to the steering head. In one or more embodiments, the pump for each fluid type, and in the embodiments discussed herein the hydraulic pump, has the capability to drive multiple hydraulic conduits from the single hydraulic fluid reservoir to service the plurality of hydraulic cylinders. In one or more such embodiments, the pump is controllable by control station 114 to select one output hose to which to pump the fluid from the input hose from the lubricant reservoir 115. In such arrangements, therefore, only one flap 50 is deployable at a time, though it should be understood that arrangements permitting simultaneous deployment of flaps can be used.
[0086] FIG. 8 is a perspective view illustrating an embodiment of fluid outlet fitting 77 threadedly positioned in and through the wall of a chamber 75C. The wall of chamber 75C within cover 75 is generally C-shaped in its cross section by a vertical plane that includes or is otherwise parallel to the interior body axis (in one or more embodiments, coextensive with auger axis 16, FIG. 1) when cover 75 is in its closed position as in FIGS. 3 and 7. The wall of cover 75 is generally C-shaped in its cross-section by a plane that is perpendicular to axis 16 (FIG. 1) when cover 75 is in its closed position. Thus, cover 75 and the chamber 75C wall define an interior volume bounded on three sides by the chamber 75C wall and on three sides by the walls of cover 75. The chamber wall is welded onto the inner surface of cover 75 at, in one or more embodiments, a rearward end of second outer tube 73, as shown in FIG. 8, or, in one or more other embodiments, slightly rearward of the center of second outer tube 73, as shown in FIGS. 2 and 10 or up to about midway along the length of cover 75. A through slot 74 (FIGS. 2 and 10) is defined through each of the side walls of cover 75 that form the chamber, so that the through slot fluidly connects the volume defined by the chamber wall and cover 75 with the exterior of cover 75. In one or more embodiments, the cover defines two through slots 74, a respective one on either opposing side of cover 75 in communication with the interior of chamber 75C. About the exterior of its end extending into the interior of cover 75 from the fitting's attachment to the chamber wall, fluid outlet fitting 77 defines a male thread to which a female threaded connector at an end of the lubricant fluid supply hose 105 (FIG. 1) connects, thereby fluidly connecting the interior of lubricant fluid supply hose 105 to the interior of fitting 77 so that fluid from fluid supply hose 105, driven by fluid source 115 and its pump 147 (FIG. 1), flows into the volume defined by the chamber 75C wall and cover 75. As noted above, the respective fluid source 115 and fluid supply hose 105 provide, in one or more embodiments, bentonite, which has a specific gravity higher than water, sand, and soil. Thus, under pressure from the pump 147 that is part of and controlled by the steering head control station 114 at the auger machine (FIG. 1) automatically or directly by the auger machine's operator through a user interface, bentonite is forced into the volume defined by the walls of chamber 75C and cover 75 and out to the exterior of cover 75 through the through slot(s). Due to the disposition of cover 75 on upper exterior surface 99A (FIG. 3) of second outer tube 73, the fluid expelled through the through slot(s) moves downwardly over the exterior of second outer tube 73 due to the force of gravity to lower exterior surface 99B (FIG. 3) of second outer tube 73. The bentonite thereby tends to fill the interstice between the outer wall of second outer tube 73 and the bore wall. As the steering head moves forward under the urging of the auger machine, the outer surfaces of a sequence of pipe casings or extraction tubes welded or otherwise secured to the rear end of the steering head's second outer tube 73 engages the bentonite, which lubricates the casings' or extraction tubes' movement through the bore.
[0087] FIG. 11 is a front perspective view of a steering head illustrating a cutting head 176 of steering head 10. Steering head 10 includes a cutting head 176 having a central body 207 and a plurality of roller cone-type cutting bits 209 attached at respective peripheral positions on central body 207. Cutting bits 209 may each have cutting portions thereon that are configured to cut through underground material such as rock. As steering head 10 is rotated about a rotational axis (e.g., axis 16), each of cutting bits 209 may generally remain in the same position relative to central body 207. In other embodiments, as discussed further herein, cutting bits may expand outwardly upon rotation of a steering head so that a steering head is capable of having a larger cutting area.
[0088] Cutting head 176 is merely one example of a cutting head that may be used within steering head 10. In some embodiments, cutting head 176 and/or any cutting bits thereon may be removable so that another cutting head may be used in its place. This feature may be beneficial to enable customization of cutting heads 176 so that steering head 10 may be tailored to the particular use case. For example, whenever steering head 10 is being used to extract different types of material, different types of cutting heads may be selected to optimize performance of steering head 10.
[0089] FIG. 7 is a rear perspective view illustrating steering head 10 of FIG. 3 and, in particular, cover 75. Cover 75 is pivotably attached to second outer tube 73 via hinge 75A. Internal volume 75B is defined between cover 75 and the exterior surface of second outer tube 73, and various conduit lines are positioned in internal volume 75B, including communication line 104, a water hose 105, a lubricant fluid supply hose 105, and hydraulic hose 105.
[0090] Referring to FIGS. 1, 7, and 14, a rear portion of the section of auger 112 received within the steering head is illustrated within second outer tube 73. Center portion 112A of auger 112 defines a center hole 112B at the steering head auger section's rear end that extends for a short length into center portion 112A along axis 16 and that facilitates connection of this front section of auger 112 initially to a second section of auger 112 that extends through an initial pipe casing or extraction tube section welded to the rear edge of second outer tube 73. The second auger section has a male front end that is matingly received within center hole 112B in the steering head auger section, so that rotation of the second auger section rotates the steering head auger section. The second auger section, in turn, has, at its rear end, a center hole 112B that is the same as the center hole of the steering head auger section. This center hole of the second auger section matingly receives a male front end of a drive output of auger machine 11 (see FIG. 1), so that rotation of the auger machine's drive output rotationally drives the second auger section and, thereby, the steering head auger section. As discussed below with respect to FIG. 14, a pin extends radially (with respect to axis 16) through the rear end of the second auger section and the drive end of the auger drive output, so that the auger sections move with the auger machine in both the forward and rearward directions along the body axis.
[0091] The steering head and the initial casing/extraction tube section are initially disposed in the starting pit. The pit is dug to receive the auger boring machine at a depth that permits the auger machine's disposition, and the alignment of auger portion 112A, so that center axis 16 and the body axis are horizontally aligned with the center line of a desired bore to be dug through the earth beginning at a vertical wall in the starting pit. The steering head and initial casing/extraction tube section are disposed on a track laid upon the pit's typically horizontal floor, thereby aligning the steering head and casing/extraction tube section in the desired orientation at which to cut into the pit's forward wall face. The casing section or extraction tube section has a hinged cover 131 (as discussed above; see also FIGS. 17 and 18), like the hinged cover at the top of the steering head's second outer tube 73, disposed on the casing/extraction tube section so that the cover is aligned front-to-back with the cover on the second outer tube. The front of the cover 131 on the casing/extraction tube section is open to, and abuts the open rear of the cover 75 on the second outer tube so that, when both covers are closed, the two covers define an enclosure for conduits from the auger machine control station extending from the rear end of the rearmost casing attached to the steering head up to annular ring 43 at the rear of the steering head's first outer tube 71. Further, the casing sections and the extraction tube sections have approximately the same outer diameter measured in a plane perpendicular to axis 16, so that the outer surface of the generally cylindrical casing section or extraction tube section defines a generally continuous generally cylindrical outer surface with second outer tube 73. In one or more embodiments, the covers 131 on the casing sections and extraction tube sections are generally the same dimensions as the cover 75 on second outer tube 73. Thus, like the cover 75 on second outer tube 73, the cover(s) on the sections of pipe casing or extraction tube directly or indirectly attached to the steering head, e.g. as described herein and in one or more embodiments, does not extend radially beyond, and in some embodiments has a maximum radial distance from axis 16 that is within, the maximum radial perimeter about axis 16 of first outer tube 71, e.g. as defined by a forward ring 44. The conduits extending between the auger machine steering head control station 114 and the steering head's first outer tube are laid into the open covers 75 and 131, and the covers are closed.
[0092] The auger machine, which is mounted movably on the track, receives the rear end of the initial casing section, or of an initial section of extraction tube section, within a depression in the face of the machine. Moving forward on the track, the auger machine thereby applies forward pressure to the casing section or extraction tube section, which in turn applies corresponding force on the steering head. Thus, by moving forward, the auger machine pushes both the auger and the initial casing/extraction tube section forward into the rock or earthen face of the pit. The auger machine is not otherwise attached to the pipe casing sections to enable the auger machine to pull the casing sections rearward. Thus, while the auger machine can push the casing sections forward, it cannot, in one or more embodiments, pull the casing sections rearward. On the other hand, as described below, the auger machine attaches to the extraction tubes, in one or more embodiments, so that its movement forward and rearward on the track respectively pushes the extraction tubes forward and pulls them rearward, along axis 16.
[0093] As the cutting head initially engages the wall face, and as the auger machine rotates the auger and pushes the auger and the steering head forward, the rotating cutting head is pushed into the wall face, cutting the desired bore. The auger directs the resulting debris rearward though the steering head and the casing/extraction tube section(s) until depositing the debris in the starting pit, from which it can be removed. When the steering head moves sufficiently into the bore that the rear edge of the initial casing section or extraction tube section remains outside of, but is mostly within, the bore, the operator disengages the auger machine from auger center portion 212A by removing the interlocking pin passing through the auger machine's drive portion and the rear end of the auger section (and, in the event extraction tube sections are used, similarly disengages the auger machine from the extraction tube section) and controls the auger machine to move the machine rearward on the track, such that the steering head and casing/extraction tube section remain in their position in the bore as the auger machine retreats. A second casing section is welded to the rear end of the preceding casing section, or a second extraction tube section is attached to the end of the preceding extraction tube section, as the case may be. A third auger section, having a center section with a male forward end configured to matingly engage into center hole 212B of the second auger section and a center hole at its rear end like that of center hole 212B, is similarly attached to the second auger section at the third auger section's front end and to the auger machine's male drive output at the third auger section's rear end. The auger boring machine's auger drive output is matingly connected into center hole 212B of the third auger section (and attached thereto with a pin), and the rear of the second casing/extraction tube section is received in the front face depression of the auger machine (and, in the case of an extraction tube section, is attached to the forward end of the auger machine), in the same manner as the auger machine was connected to the second auger section and the first casing/extraction tube section.
[0094] As indicated above, the second casing/extraction tube section, like the first, has a hinged cover 131 on its top, like hinged cover 75 on second outer tube 71, and the open forward end of this cover abuts and is aligned with the open rear end of the cover on the first casing/extraction tube section, so that the cover on the second casing/extraction tube section continues the conduit enclosure rearward to the rear end of the second casing/extraction tube section. The conduits extending between the auger machine's steering head control station 114 and the hinged cover of the first casing/extraction tube section are laid into the open cover 131, and the cover is closed. The auger boring machine again rotates the auger and pushes forward on the auger and the casing/extraction tube section, thereby pushing the steering head further into the bore and pushing the third auger section, now within the second section of pipe casing or extraction tubing, into the bore being dug by the steering head. As auger machine 11 (FIG. 1) rotates auger 112 (FIG. 1), thereby enabling the cutting head to continue the tunneling operation through the earth or rock material, the rotating auger continues to move the material cut by the cutting head rearwardly through the steering head and the casing/extraction tube sections until it is deposited into the auger machine pit. As the bore hole is lengthened in this manner, this process repeats, so that additional auger sections are sequentially added to the immediately preceding auger sections that are pushed into the bore, and additional pipe casing/extraction tube sections are sequentially welded or otherwise attached to the immediately preceding casing/extraction tube sections as they are pushed into the bore, until a desired bore is completed.
[0095] A pit is also dug (e.g., prior to excavating the bore) at the termination of the desired bore path, so that as the bore is completed, the steering head emerges into the destination pit. To disassemble the boring assembly, the electrical and fluid conduits are disconnected from the steering head and pulled from the steering head and otherwise back through the bore by the operator in the starting pit. The steering head is detached from the initial casing or extraction tube section (e.g., by cutting, where the initial casing head or extraction tube is welded to the steering head). As discussed below, where the cutting head has retractable cutting bits, the bits can be put into their retracted positions, and the steering head's outer tubes and body are then pulled over and away from the cutting head and the first auger section. Alternatively, the cutting head may be removed from the auger before the steering head is removed. The cutting head is then removed. If the boring system is used to install pipe casing sections, a cleaning pig is attached to the front end of the auger in the cutting head's place. As should be understood, a cleaning pig is a device that generally conforms to the bore's diameter. In the starting pit, the auger boring machine is then moved rearward, pulling the accumulated auger sections, and the pig, back rearwardly into and through the bore. As the pig moves through the bore, it collects debris in the casing, pulling it back to the starting pit, where it is eventually deposited, as it moves back through the bore. As each auger section is pulled fully back into the starting pit, an operator disconnects it from the next-forward auger section to which it is attached (e.g., by removing the interlocking pin) and from the auger machine's auger drive (e.g., by removing the interlocking pin). An operator then controls the auger machine to move forward on the track, up to that next-forward auger section, and secures its auger drive to the rearward end of that section. The operator then moves the auger machine rearwardly on the track, pulling that next auger section into the starting pit for removal. This process is repeated until all auger sections and the pig or cutting head (if not removed in the termination pit) are removed from the bore.
[0096] If the auger system has created the bore with the use of pipe casing sections, the auger machine's withdrawal does not remove the casing sections because, while the auger machine receives the rear end of the rearmost pipe casing in an abutment, so that the auger machine can push the casing section(s) forward into the bore, the auger machine is not connected to the pipe casing section(s) to apply force in the rearward direction. Thus, in that instance, the auger machine's movement only removes the auger sections. The pipe casing sections remain in the bore, and a utility line (e.g., power, water, sewer, telecommunications, etc.) may then be run through the interconnected casing sections that remain in the bore.
[0097] On the other hand, as described below, if the auger system has created the bore with the use of extraction tube sections that are intended to be removed from the bore once the bore is created, the auger machine is attached to the extraction tube sections to apply force in both the forward and rearward directions. Thus, in that instance, and after the steering head and the cutting head have been removed at the termination pit, the auger machine's rearward movement described above pulls both the auger sections and the extraction tube sections into the starting pit. No cleaning pig is needed, as removal of the extraction tube sections itself generally clears the bore of remaining debris. However, plastic tubing or other lining material may be attached to the forwardmost extraction tube so that extraction of the extraction tube sections simultaneously pulls the bore lining material into the bore. At the starting pit, an operator removes the extraction tube sections sequentially from each next-forward extraction tube section along with the auger sections, until all extraction tube sections and corresponding auger sections are removed from the bore.
[0098] FIG. 12 is a perspective view illustrating a hydraulic cylinder 128 that, in one or more embodiments, is utilized within a steering head as discussed above to move a steering flap between its extended and retracted positions. As reflected in the discussion above, there are, in the embodiments discussed herein, four cylinders 128 (in other embodiments, eight cylinders 128, two for each flap) respectively disposed in the gap between the steering head interior body and the first outer tube underneath the openings in the first outer tube in which the four flaps are also disposed. Each cylinder is disposed operatively between an outer surface of the steering head's interior body and the under surface of the flap so that operation of the cylinder moves the flap about its hinge pivot position. Hydraulic cylinder 128 comprises a body 130, a first member 132A, a second member 132B, and a hydraulic connection port 132C. Referring also to FIG. 1, a hydraulic hose 105 extends from the auger machine control station and through the enclosures between the interiors of covers 131 and the exteriors of the intervening pipe casing/extraction tubes, then through the enclosure of cover 75 (FIG. 1) and the outer surface of tube 73 (FIG. 1), through the through-hole in ring 43 and into the volume between the interior steering head body and tube 71, to hydraulic cylinder 128 (there are eight hydraulic lines, one to and one from each hydraulic cylinder, driven by pump 147, as discussed with respect to and indicated in FIG. 1) beneath its respective flap in its opening in the first outer tube. The hydraulic line connects to connection port 132C to provide hydraulic fluid to hydraulic cylinder 128. First member 132A is generally in the shape of a circular tube, and second member 132B is generally in the shape of a cylinder. Second member 132B is, in the illustrated embodiment, received within first member 132A so that the first and second members expand and retract (as illustrated in FIG. 12) in a telescoping manner. To reach an expanded state, first member 132A and second member 132B move in the direction indicated by arrow C1 relative to body 130, with center piston 132B extend upward, above surrounding annular member 132A. A base surface 132D of hydraulic cylinder body 130 is attached to outer surface 33 of auger interior body 23 (see FIG. 1) (e.g., by a pair of bolts that extend through the hydraulic piston body and through the steering head interior body, and by an enclosure ring that surrounds the hydraulic cylinder base and that is welded to the steering head interior body exterior), while a distal end of second member 132B abuts first flap face 79A (see FIG. 1) of steering flap 50 (see FIG. 1). Alternatively, in one or more other embodiments, the hydraulic cylinder is reversed, so that base surface 132D is attached to first flap face 79A of steering flap 50, and a distal end of second member 132B abuts the steering head interior body exterior surface. Piston 132B engages the underside of its respective flap 50 (FIG. 1) when the hydraulic cylinder expands to move the flap outward.
[0099] The use of a telescoping hydraulic cylinder 128 enables hydraulic cylinder 128 to fit within a small space, relative to non-telescoping designs, thus enabling the depth of the gap between the steering head interior body and the inner diameter of first outer tube 71 (see FIG. 1) to be small. As a result, interior body 23 and interior volume 125 (FIG. 1) are, in one or more embodiments, enlarged beyond what would be available with the use of a hydraulic cylinder having a non-telescoping piston (though it should be understood that the use of a non-telescoping piston is within the scope of the present disclosure). Thus, the design of hydraulic cylinder 128 may allow for an increased amount of material to be extracted through interior volume 125 due to the increased cross-sectional area of the interior of the steering head interior body and corresponding increased volume of interior volume 125.
[0100] FIG. 13 schematically illustrates a hydraulic cylinder 128 as in FIG. 12 positioned within a through opening 91 in the body of first outer tube 71. The steering flap above the cylinder has been made partially transparent to allow components positioned between steering flap and the underlying steering head interior body to be seen. In the illustrated embodiment, only one hydraulic cylinder 128 is disposed below the flap, with hydraulic cylinder 128 being positioned proximate to a center of the flap and through opening 91. However, in other embodiments, multiple hydraulic cylinders, or actuators other than hydraulic cylinders, may be disposed operatively between the steering head interior body and the steering flap to move the steering flaps to move the flaps between their retracted and extracted positions. Additionally, stops are, in one or more embodiments, positioned on the steering head interior body exterior beneath opening 91 to assist in controlling steering flap positioning. The stops are bumpers disposed on the steering head interior body exterior so that the flap inner surface comes to rest on the stops when the flap reaches its fully retracted position, thereby stopping the flap's further movement radially inward into the gap between the steering head interior body and the first outer tube and maintaining a gap between the flap's inner surface and the steering head interior body outer surface within which the corresponding hydraulic piston can reside. A stop 134A is positioned towards the forward end of flap 50 (toward the left in the perspective of FIG. 13) and two stops 134B are positioned towards the rear (distal) end of the flap (toward the right in FIG. 13).
[0101] FIG. 14 is a perspective view illustrating a section of an auger 112 as in FIG. 1 and that comprises a center portion 112A and a helical screw blade 113A extending radially outward from center portion 112A and defining a contact portion 113B along the outer perimeter thereof. In one or more embodiments, contact portion 113B contacts and slides against the surrounding inner wall of auger interior body 23 (FIG. 1) with an approximately clearance, as discussed above. To provide sufficient strength at contact portion 113B to withstand forces applied to the blade at the engagement between the blade and the auger interior body 23 inner wall, the thickness of blade 113A (parallel to the auger axis) is greater at contact portion 113B than in the portion of the blade inward of the contact portion. In some embodiments, contact portion 113B of the auger section located in the steering head may possess a thickness of about 1.5 to about 2 or more while the blade thickness inward of the contact portion is about 0.5 thick, though it should be understood that the thickness of the inner diameter may vary with variance in the weight of the cutting head. As discussed below, however, in one or more embodiments, the auger blades of the auger sections in the casing sections or extraction tube sections rearward of the steering head do not contact the inner volume surfaces of those casing or extraction tube sections. Thus, the blades of those auger sections are, in one or more embodiments, not as thick (in a dimension parallel with axis 16 (FIG. 1)) as the blade of the auger section disposed within the steering head, e.g. about thick. Additionally, as discussed above, in some embodiments, a lubricant (e.g., water) may be used to lubricate contact portion 113B at its interface with the inner wall surface of interior steering head body 23 (FIG. 1), to thereby reduce friction forces.
[0102] As discussed above, a hole (countersunk in one or more embodiments) 112B aligned with the axis of center portion 112A (see 16, FIG. 1) is provided at the rearward end of center portion 112A, while on the forward end of the center portion an extension 112C extends forward of the main center portion and blade. In the illustrated embodiment, the inner wall of hole 112B is hexagonal in cross section (in a plane normal to the center portion's axis of elongation), and the exterior wall of extension 112C has a complementary hexagonal cross sectional shape of a dimension so that extension 112C is slidably receivable into the hole 112B of the next forward auger section but so that the opposing flat sides of extension 112C prevent the extension's rotation relative to the flat sides of the inner wall of hole 112B, thus keying the extension of the rearward auger portion to the hole of the forward auger section and translating the rotation imparted to the rearward auger section (by the auger boring machine or a still more rearward auger section) to the forward auger section. As illustrated in FIG. 14, a through hole is drilled through extension 112C so that the through hole passes through two opposing flat sides of the extension, while a corresponding through hole passes through the rear end of center portion 112A and countersunk hole 112B. The holes in the extension and the countersunk hole are positioned so that when the extension 112C is fully inserted into the hole 112B of the next forward auger section (so that the main center portions of the two sections abut), and when the rear auger section is rotationally aligned with respect to the forward auger section so that the auger blades of the two sections align in a continuing helical curve, the through hole in the rearward section's extension 112C aligns with the through hole that extends through hole 112B, allowing a pin to be inserted through those holes to thereby axially retain extension 112C of the rearward auger section within the hole 112B of the forward auger section. An elongated pin 119 is shown in FIG. 14 for purposes of illustration, but it will be understood in view of the present disclosure that the pin used in operation will not, in one or more embodiments, extend significantly beyond the outer wall of center section 112A. Thus, a sequential series of auger sections may be assembled as the steering head moves through the bore, as discussed above.
[0103] In one or more embodiments, the initial auger section, disposed in the steering head, is an exception to the arrangement of auger sections having a forward male connection end and a rearward female connection. This initial auger section, unlike subsequent auger sections, has female connection structures 112B at both the forward and rearward ends of the auger section's central portion 112A, rather than having a male connection portion 112(c) in the front. This allows the initial auger section to receive a male connection portion from the cutting head, as described below. It should be understood, however, that this arrangement is for purposes of example only and that other configurations could be used at the front of the initial auger section and at the rear of the cutting head.
[0104] Where the auger system is not used in association with pipe casing sections, the system, in one or more embodiments, may be used instead with other types of enclosures for the auger. In one or more embodiments, the enclosures, like the example pipe casings discussed herein, are attached to the rear of the steering head, or otherwise sequentially with each other, and enclose the auger. Unlike the pipe casing sections, however, the enclosures are not left in the bore after the bore's creation and are, instead, extracted with the auger after the bore is completed. These enclosures are referred to herein as extraction tubes. In one or more examples as discussed herein, extraction tube sections are generally cylindrical in shape, similar to the outer shape of pipe casing sections, and similarly have conduit covers 131 (FIG. 1), but it should be understood that this is for example only. FIG. 17 provides a perspective view of two auger sections (one section being visible in FIG. 17), referred to collectively as auger 112 with respect to FIG. 17, received within two extraction tube sections 123, identified in FIG. 17 as 123A and 123B. Auger 112 is constructed and operates as discussed above with respect to auger 112 of FIG. 14 and auger 112 of FIG. 1, with exceptions as noted herein. Thus, in this example, auger 112 comprises a center portion 112A and a helical screw blade 113A extending outward from center portion 112A. Auger 112 also comprises a distal edge 113B along the outer perimeter of helical screw blade 113A. A hole 112B, with polygonal sides, extends into one end of center portion 112A (a similar hole exists in the rear of the forward auger section), and a correspondingly polygonal male member (not shown) extends from the opposite side of the center portion to be received by the corresponding hole in the rear of the center portion of the auger section in forward extraction tube section 123A, as discussed above with respect to FIG. 14.
[0105] Additionally referring to FIG. 1, and as discussed above, the diameter of the generally cylindrical outermost surface of each extraction tube section, in one or more embodiments, is approximately the same as the diameters of the generally cylindrical outermost surfaces of pipe casings 108 and rear outer steering head tube 73. This outermost surface is defined by a cylindrical outer body tube portion that is disposed radially outward of a generally cylindrical extraction tube interior body having dimensions similar to those of steering head interior body 23. As with the steering head interior body and its outer tube 71, the extraction tube interior body and its outer body tube are secured with respect to each other by longitudinally aligned plates welded to the exterior of the former and the interior of the latter. Still referring to FIG. 1, it will be apparent that the center axis of the generally cylindrical extraction tube section outer tube is offset from the auger axis. As the exterior surface of the extraction tube interior body is generally concentric with the exterior surface of the extraction tube outer tube wall, and the wall thickness (in the radial direction) of the extraction tube interior body is generally the same about the interior body, the center axis of the extraction tube interior body is generally the same as that for the outer tube and is, therefore, also offset from auger axis 16. In one or more embodiments, however, the auger blade on the auger sections rearward of the first auger section (in the steering head) is smaller than the auger blade of the first auger section, such that the diameter of the cylinder defined by auger blade distal edge 113B on those rearward auger sections is less than the diameter of the cylinder defined by auger blade edge 113B in the first auger section. In such embodiments, the reduction in auger blade diameter in the rearward auger sections is sufficient to accommodate the offset between the auger rotational axis 16 and the axis of the generally cylindrical interior surface of the extraction tube interior body so that the auger blades of the rearward auger sections do not contact the interior surface of the extraction tube interior body during use. In one or more embodiments, auger sections with blades of the same or similar diameter are also used in cutting bores for use with pipe casings 108. In such embodiments, and in contrast to the embodiments as illustrated in FIG. 1, the auger blades of the rearward sections do not extend out in the radial direction as far as does the auger blade in the auger section disposed within the steering head.
[0106] Accordingly, and referring again to FIG. 17, auger 112 is positioned within a generally cylindrical interior volume 125 defined by the interior surfaces of the extraction tube interior bodies and that extends through first and second extraction tube sections 123A and 123B, with auger 112 being rotatable within interior volume 125 about auger axis 16 extending through lead end 124 and rear end 126 but without contacting the inner wall of the extraction tube interior bodies. As noted above, in one or more embodiments, the auger blade similarly does not contact the interior wall of pipe casings (see 108, FIG. 1) when pipe casings, rather than extraction tubes, are attached to the steering head rear as it makes its way through the bore. While the radial thickness of the pipe casing sections may vary, their internal diameter is generally greater than the outer diameter of the helical blade of auger 112 (so that that auger can move axially within and rotate with the pipe casing sections). Thus, in such embodiments in which extraction tubes are used, there is a void in the radial direction between the outer surface of the extraction tube interior body and the inner surface of the extraction tube outer tube. Similarly, in such embodiments in which pipe casings are used, there is a void in the radial direction between the auger blade distal edges and the inner surface of the casing sections. In either arrangement, the void extends from the steering head to the rearmost extraction tube section or pipe casing section, thereby allowing light from steering LEDs (discussed below) mounted to the steering head to be seen from the auger machine pit. It also, due to noncontact between auger blade distal end 113B and the inner wall of the extraction tubes' interior bodies or the interior wall surface of casing sections, eliminates friction drag on the distal edge of the auger blade as the auger rotates rearward of the steering head.
[0107] At each of the forward and rearward ends of each extraction tube is an annular ring (one of which is illustrated in FIG. 17) that generally encloses the gap between the extraction tube section's interior body and its outer tube. In each annular ring is an arcuate through hole 129 (one of which is shown in FIG. 17). Each annular ring is oriented on its end of its extraction tube so that the two arcuate through holes 129 are rotationally (about the axis of the generally cylindrical interior body and outer tube) aligned with each other, just inward of the top of the extraction tube section and immediately below the extraction tube section's cover 131. The similarly aligned through holes of the extraction tubes sequentially attached behind the steering head align with each other when the extraction tubes are assembled. Through holes 129 thereby permit a line of sight from the auger machine/starting pit, through the annular rings and through the void between the extraction tubes' interior bodies and the extraction tubes' outer tubes, to the steering LEDs at the steering head, as described below.
[0108] The combined auger assembly within the assembled extraction tube sections connects, at its forward end, to the rear end of the auger section disposed in the steering head 10 (FIGS. 1-4, 7) and, at its rearward end, to the forward-facing drive output of auger machine 11 (FIG. 1), as described above. The auger assembly's forward-facing extension member is received into the polygonal hole in the end of that next-forward auger section, and the auger sections are locked together with radially extending through-pins, as discussed above. The auger assembly's rearward-facing polygonal locking hole receives the auger machine's polygonal forward-facing drive output, and the auger section and drive output are similarly locked together with radially extending through-pins. Each extraction tube section, e.g. 123A and 123B, in the example configuration as illustrated in FIGS. 17 and 18, connects, at its forward end, either to the rear of steering head or to the rear of a next-forward extraction tube section, as described below. The rearmost extraction tube attaches to a forward face of the auger machine, as described below.
[0109] In one or more embodiments, extraction tube sections, e.g. 123A, 123B, etc., are attached together using fasteners. This may be advantageous to enable the sections to be easily separated from each other as each rearmost section is pulled back into the starting pit, as described above, though it should be understood that in other embodiments the sections are attached together by welding instead of removable fasteners. Referring to FIGS. 17 and 18, for example, the rear end of extraction tube section 123A abuts the front end of extraction tube section 123B at an intersection 133, and the two sections are aligned with each other rotationally about the axis of their elongation so that the hinged covers 131 (which are like hinged cover 75 (FIG. 1) of the steering head, but without a fluid chamber and slit) at the tops of the extraction tube sections are aligned so that each cover 131 opens at its ends to the covers of the adjacent extraction tube sections. When the extraction tube sections are so positioned and aligned with respect to each other, four angularly spaced apart through holes 135 in the rear annular ring of an extraction tube section (e.g., 123A) ahead of a following extraction tube section (e.g., 123B) (through holes 135 in the rear annular ring of extraction tube section 123A not shown in FIG. 18 but are the same as through holes 135 seen in FIG. 18 in the rear annular ring of extraction tube section 123B) align with four threaded holes (not shown) extending into the forward annular ring (not shown) of the following extraction tube section (e.g., 123B). Four fasteners 136, e.g. threaded bolts, are inserted through the through holes 135 of the rear annular ring of the forward extraction tube section (123A) and into, and threaded into, the threaded holes of the forward annular ring of the following extraction tube section (123B) to thereby secure the extraction tube sections to each other. Recesses 137 are provided in the forward extraction tube section (123A) proximate to interface 133 so that through holes 135 may be accessed and to facilitate installation of fasteners 136. Further, in one or more embodiments, the rear annular ring of the forward extraction tube section (123A) and the forward annular ring of the following extraction tube section (123B) each defines a pair of countersunk bores 138 spaced 180 apart from each other and aligned with the countersunk bores 138 on the opposing extraction tube section annular ring. Each opposing pair of countersunk bores receives a dowel, thereby reinforcing the rotational attachment of the extraction tube sections to each other.
[0110] The front face of auger machine 11 (FIG. 1) defines four similar threaded holes that align with through holes 135 in the rear annular ring of the last of the last extraction tube section. To drive the steering head deeper into the bore, the operator moves the auger machine up to the rear extraction tube section, until the front face of the auger machine is flush against the rear face (in this instance, the rear annular ring) of the last extraction tube section. With the extraction tube section lying on the auger machine track, and with the extraction tube section's hinged cover at the top, aligned with the other covers ahead, the four through bores 135 at the rear annular ring of the rearmost extraction tube section align with the four threaded bores in the auger machine front face. The operator then inserts a threaded bolt through one of the open through bores in the rear extraction tube section's rear annular ring and threads the bolt into the threaded hole in the auger machine front face, thereby securing the extraction tubes to the front of the auger machine. Thus, the auger machine's subsequent movement on the track toward the bore pushes the steering head and extraction tubing further into the bore, while the auger machine's movement on the track away from the bore pulls the extraction tubing out of the bore and into the start pit. The front extraction tube section is welded or bolted to the rear end of the rear outer tube 73 (FIG. 1) of the steering head.
[0111] As noted, each forward extraction tube section (123A) also comprises a cover 131 attached to exterior surface 157 of the forward extraction tube section via a hinge 139, and each following extraction tube section (123B) comprises a cover 131 attached to exterior surface 157 of the following extraction tube section via another hinge. Covers 131 define a volume between the inner surface of the covers and the outer surface of the extraction tube sections that extends parallel to axis 16, and one or more conduit lines may be received within this volume so that they are protected by covers 131. The cover on the outer cylindrical body of the forwardmost extraction tube section, immediately behind the steering head, aligns with and abuts the rear end of cover 75 (FIGS. 1/2) of the steering head's rear outer tube so that the volume under the covers 131 (which may be extended by the addition of additional extraction tube sections as discussed herein) aligns with the volume under cover 75 (see FIG. 1 and volume 75B, FIG. 3), providing a continuing enclosure through which pass the conduit lines from the auger machine control station. A similar enclosure is provided by the covers 131 on the pipe casings 108 (FIG. 1).
[0112] As discussed above, a water hose may extend from the auger machine steering head control station (see 114, FIG. 1), through the cover volumes (on either extraction tube sections or pipe casing sections, as the case may be), to the front of steering head 10 (FIG. 1) to output water onto the cutting head to cool the cutting bits. That water, along with cut rock and earth debris, falls back behind the cutting head and is driven rearward by the rotating helical auger blade. The water and debris tend to be located on the radially outward part of the helical blade, so that the water acts as a lubricant between the auger blade edge and the inner body wall of the steering head interior body 23 (FIG. 1). To further assist the auger blade edge withstand friction between the blade edge and the body wall, as discussed above, the auger blade (at least of the auger section within the steering head) is thickened at the edge, which in one or more embodiments is thicker (in the shortest dimension across the auger blade at a given point on the auger blade, perpendicular to a radius extending from the auger's rotation axis 16, FIG. 1) at the blade's radially outer edge than at the base of the blade, the portion of the blade extending immediately radially outward from the auger's center portion 112A (FIG. 1).
[0113] Still referring to FIG. 17, and as discussed above, the rearmost extent of the sight line through the void between the extraction tube interior body and the extraction tube outer body tube, extending from the rear of the steering head and through the assembled extraction tubes, is, in the example of assembled extraction tubes 123A and 123B, through hole 129, where the void extends through the rear face of the rearmost extraction tube section. In assemblies in which the steering head pulls pipe casing sections through the bore, as discussed above, the void is defined between a cylinder defined by the distal edge (see 813B, FIG. 14) of the helical auger blade and the pipe casing sections' inner walls (at the top). Unlike the void arrangements utilizing extraction tube sections, the forward and rearward annular ends of the void in arrangements utilizing pipe casings are not closed. As described above, in either type of arrangement, the void extends all the way from the forward extent of the assembled extraction tube sections or pipe casing sections to the rearward extent thereof, thereby allowing light to pass through the void's length, parallel to the extraction tube section or pipe casing section inner volume axis.
[0114] As indicated above and referring to FIG. 19, in either type of arrangement, the void allows light from steering light elements, e.g., elements 141A-141C, disposed in the steering head, as discussed below, to extend through the void 127, which begins as the volume defined between distal edge 113B of the helical auger blade and inner wall surface 69D of the second outer tube (FIG. 19) and continues as the volume between the extraction tube sections' interior bodies and the extraction tube sections' outer bodies, where extraction tube sections are utilized, or between the auger blade and the inner wall of pipe casing sections (in one or more embodiments a radial distance in a range from about 4 inches to about 12 inches, where pipe casing sections are utilized, to the rearmost extent of the auger assembly at the starting pit. In one or more such embodiments, steering head 10 (FIG. 1) comprises a plurality of light elements 141A, 141B, and 141C, e.g. light emitting diode (LED) elements disposed and configured to emit light from the rear of the steering head into the void so that light from the elements is visible at the rear of the pipe casing assembly, or at opening 129 (FIG. 17) at the rear annular ring of the rearmost extraction tube section, as the case may be, connected in sequence and extending rearward from the steering head. LED elements 141A-C are powered and controlled by auger machine steering head control station 114 (FIG. 1), from which power wires (not shown) extend, through covers 131 and 75 to the respective LED elements. The light elements may be disposed at various locations on the steering head. In the presently described embodiments, for example and referring to FIGS. 1 and 19, the light elements are disposed at the rear of steering head interior body 23 and first outer tube 71 in rear annular ring 43 so that the light elements direct light rearwardly into the void such that the lights are visible to a viewer standing in the starting pit behind the steering head and looking into the rear end of the void. But in other embodiments, for example, the light elements are mounted to the interior of the steering head's second outer tube 73, for example at the rear of the second outer tube. In one or more embodiments, the light elements are positioned to emit light into a volume defined by the pipe casings or the extraction tubes so that the light is visible at the rear of the pipe casing section assembly or the extraction tube assembly, as the case may be, by an observer in the starting pit.
[0115] Referring to FIGS. 1 and 19-22, in one or more embodiments, the steering head includes a light assembly 142 that includes the three light elements 141A, 141B, and 141C. Light assembly 142 includes a first, generally planar, bracket 143A having an arcuate inner edge 144 and a generally arcuate outer edge 145, so that bracket 143A is itself generally arcuate in shape. In the illustrated embodiment, the curve of inner edge 144 defines an arc that is part of a circle of a radius generally equal to the radius of the outer surface of steering head interior body 23 (FIG. 1) and the inner surface of annular ring 43 (FIG. 1), and in one or more embodiments bracket 143A is mounted by welding within a gap made in annular ring 43 to fit bracket 143A. LED light elements 141A, 141B, and 141C are mounted on bracket 143A with their centers on an arc concentric with the arc of edge 144 and so that center light 141B is disposed at the top of the steering head interior body rear perimeter and, thereby, in embodiments having the extraction tube sections as discussed herein, aligned midway within the field of view presented to the viewer in the starting pit by opening 129 (FIG. 17). Light elements 141A and 141C are offset from either side of center light 141B so that light from each is also in the field of view presented to the starting pit view by opening 129. The width of opening 129 should be large enough to encompass the distances the LEDs themselves are separated, in one or more embodiments, e.g., by approximately six inches from center to center of each pair of adjacent LEDs. Thus, from the standpoint of an operator of auger boring machine 11 at the starting pit, looking into opening 129 (in embodiments utilizing extraction tube sections) or into the opening between the auger blade edge and the inner diameter of the pipe casings (in embodiments utilizing extraction tube sections), light 141B should (if all the augers in the sequence including and from the steering head are aligned on a straight axis 16) appear, vertically and arcuately, in the 12:00 position in a 3600 circle about axis 16 that includes the three light elements, with light elements 141A and 141C being equiangularly offset on either side of center light 141B.
[0116] In operation, however, and as described above, the operator may control the steering flaps so that the steering head turns from that dimensional alignment. Having deployed one or more flaps, as the operator continues to operate the auger boring machine to move the steering head forward into the rock or earth, the operator expects to see (either through opening 129 if extraction tube sections are used or between the auger blade and the pipe casing sections if pipe casing sections are used) light elements 141A, 141B, and 141C move from those positions in the operator's field of view, with that movement being predictable based on the operator's knowledge of the operational control the operator has applied to the steering head. Variations in hardness, density, or other characteristics in the earth or rock through which the steering head moves, however, can cause the steering head to deviate from the operator's intended path, whether that path be offset from a straight axis or along the straight axis itself. In those instances, the operator should notice movement of light from light elements 141A, 141B, and 141C in the operator's field of view that is different from the expected movement or lack of movement. Upon detecting such difference, the operator can adjust the positions of the steering flaps to bring the steering head's heading back to the operator's intended path.
[0117] In some prior arrangements, only a single light element is provided, in the position of light element 141B, or two lights of the same color are used, in the positions of lights 141A and 141C, without a center light element. Where only one light element is used, there can be circumstances in which the single light element becomes obscured, possibly creating difficulty in accurate steering. Where two light elements of the same color are used, the operator may still be able to view one of the lights when the other is obscured, thereby allowing the operator to continue to accurately steer, but there can nonetheless be confusion regarding which of the two lights remains visible and which is obscured.
[0118] In one or more embodiments, at least one of the light elements has a color or color temperature that is visually or thermally distinct from the color or color temperature of each of the other light elements. For example, either first light element 141A or third light element 141C may have a color and/or a color temperature that is visually or thermally distinct from the color and/or color temperature of the second light element 141B and the other of first light element 141A and third light element 141C. Assuming first light element 141A, for example, that light element is configured in one or more embodiments to emit light having an amber color, which may have a color temperature of around 2000 Kelvin to around 2500 Kelvin. Second light element 141B and third light element 141C are each configured to emit light having a color different from the color of first light element 141A (and in one or more embodiments have the same color as between themselves), such as a natural white light, which may have a color temperature of around 2500 Kelvin to around 3500 Kelvin. By using a color such as amber, first light element 141A may be configured to provide increased performance in foggy or dark areas. Additionally, by differentiating the color or color temperatures of the light elements, the light that is generated from each of the individual lights are more distinguishable from each other. In particular, by using three light elements, where one of the three light elements (e.g., the first light element 141A) emits light that is different from the other two, then if only two lights are visible by the observer at the starting pit, the identities of those lights will always be known. The same will be true regardless which of the three lights is chosen to have the different color light. To provide certainty in the event only one light element is visible, each light element has its own light color that is visually distinguishable from the respective colors of the other two lights. Because the three lights alternate in color, then even if two of the three lights is obscured, the operator can determine which of the three lights is obscured in view of the color and orientation of the other two and, thus, more accurately determine the steering head's actual heading and appropriate heading adjustment, if any is needed. As should be understood, deviation from an intended path may be determined by suspending two weighted strings in the starting pit behind bore, one behind the other. By aligning the two strings in the operator's field of view, the operator should expect to see the center light 141B in alignment with the strings. To the extent that is not true, the steering head is off of its desired path.
[0119] Rearward of center light 141B, within the gap formed between the steering head interior body 23 and first outer tube 71, and forward of annular ring 43, extends a second, generally planar, plate 143B upon which a position 146 sensor is disposed.
[0120] Additionally, light elements may be spread farther apart from each other relative to other light assemblies, and this may allow for even better interpolation. For example, light element 141A is spaced a distance D3 away from light element 141B, and light element 141A is spaced a distance D4 away from light element 141C. Distance D4 may be twice the value of distance D3 so that light element 141B is centered between light elements 141A, 141C. In some embodiments, distance D3 may be greater than about three inches, greater than about four inches, or greater than about five inches. Additionally, in some embodiments, distance D4 may be greater than about six inches, greater than about eight inches, or greater than about ten inches. Distances D3, D4 are measured solely based on the offset along a generally horizontal axis (assuming the steering head has a straight orientation, as described above) transverse to the bore's general axis of elongation (e.g., axis 16 in FIG. 1) between light elements, and distances D3, D4 do not account for offset along a vertical axis or an axis parallel to the bore's general axis of elongation. To the extent that there is a bend in any body within a steering head or within any cutting path, the use of three lights spread farther apart may increase the likelihood that light will still effectively shine through an opening to provide visibility.
[0121] FIG. 23 illustrates one example of a cutting head 176 for use with the steering head embodiments discussed herein with regard to FIGS. 1, 3, and 7. In one or more embodiments, the cutting head has a main body having a maximum radial dimension (in a plane perpendicular to the auger axis, e.g. 16 in FIG. 1) that is less than the radial dimension (in the same plane from the steering head interior body axis) of the inner surface of the steering head interior body 23 (FIG. 1). The cutting head has a plurality of cutting bits, in this example, wing cutters, disposed in fixed positions on the cutting head main body. Other cutting bits, for example one or more cutting bits disposed at the main body's periphery, are disposed pivotally on the main body so that the bits are pivotable between a first, retracted, position with respect to the main body so that the cutting bits do not extend radially outward of the cutting head's maximum radial dimension and a second, extended, position in which the cutting bit does extend radially outward of the cutting head's maximum radial dimension. With the one or more pivotable cutting bits in their extended positions, the cutting head cuts a bore through the rock and earth of a diameter (in a plane perpendicular to the auger axis) that is at least large enough to encompass the steering head's maximum periphery and, in one or more embodiments, that is larger than needed to encompass that periphery, as discussed above. With the one or more pivotable cutting bits in their retracted positions, however, the maximum periphery of the cutting head in a plane perpendicular to the auger axis is within the inner diameter of the steering head body, thereby allowing the auger boring machine to retract the auger, including the cutting head, from the steering head interior body, as described above, and back into the starting pit while the steering head remains in the bore. This may be desired, e.g., to change the cutting bits on the cutting head when a change in hardness of the earth or rock face is encountered during cutting of the bore.
[0122] To remove the auger through the steering head when the one or more peripheral cutting bits are in their retracted positions, the auger machine is moved rearward in the starting pit, thereby pulling the auger rearward through the steering head (and pulling the cutting head through the steering head interior body's inner volume, which is possible because the cutting bits are retracted) and the bore until the rearmost auger body section extends rearward of the bore into the pit. The auger machine is stopped, and the now exposed rearmost auger section is disconnected from both the auger machine and the next rearmost auger section and removed. The auger machine is moved forward and connected to the next auger section at the bore opening, and the process is repeated. The process is repeated until all auger sections, including the forwardmost auger section having the cutting head, are removed. If extraction tube sections are being used, the rearmost extraction tube section is disconnected from the auger boring machine before the auger boring machine begins to pull the auger sections rearward into the starting pit. If the rearmost extraction tube section is not disconnected, the auger boring machine's reward movement would pull both the extraction tube sections and the steering head back out of the bore.
[0123] Referring to FIG. 23 (assembled cutting head) and 24 (disassembled cutting head), cutting head 176 comprises a central body 148 built upon a hexagonal central shaft 148D, the rear end of which is received in a correspondingly hexagonal bore extending into the front end of the forwardmost auger section 112A (FIG. 1), at which the cutting head is secured to the auger central body by a pin (not shown) that extends through both the auger central body and hex shaft 148D. In the steering head's operation, the auger is pushed forward by the auger machine, so that the cutting head is pushed into the front face of the bore. The cutting head's rearward axial movement with respect to the central auger body is precluded in such circumstances by the pin and/or by a collar 148G that surrounds shaft 148D and that abuts a forward face of the auger central body, and/or by the rear face of shaft 148D that abuts a bottom of the forward bore into which shaft 148D is received. When the auger boring machine is moved rearward in the starting pit to pull the auger rearward, the forwardmost auger section 112A (FIG. 1) pulls the cutting head rearward through the pin's engagement. Shaft 148D is rotationally coupled, or fixed, to the auger central body by the engagement between the flat surfaces of the hexagonal sides of shaft 148D that abut the correspondingly flat sides of the hexagonal bore in the forward end of the forwardmost auger section, thus rotationally keying the cutting head to the auger section. Thus, when the auger machine rotates the auger in either rotational direction, the auger machine correspondingly rotates the cutting head.
[0124] The main, central, auger body includes 1.5-3 thick steel hub 148B with a forward generally triangularly shaped (in a plane that includes the auger axis 16, as in FIG. 1) generally planar steel plate welded to the front end of steel hexagonal shaft 148D. A through hole is provided in the generally triangular plate to permit passage of debris therethrough during the cutting head's operation. Immediately rearward of the triangular plate, and disposed between the triangular plate and collar 148G, hub 148B includes a generally rectangular (in a plane that is perpendicular to the auger axis 16, as in FIG. 1) generally planar steel plate 148C welded to the back end of the generally triangular section of the hub and to central hexagonal shaft 148D, which extends through a correspondingly hexagonal bore through the center of generally rectangular plate 148C. One of the flat sides of the triangle of the triangular plate is disposed perpendicularly to the auger axis 16 (FIG. 1). The dimension of elongation of the rearward, generally rectangular, plate that passes through auger axis 16 (FIG. 1) forms a non-zero acute angle 1 (in one or more embodiments, approximately 30) with a dimension line that is parallel to the rear edge of the generally triangular section, passes through the auger axis, and is in a plane perpendicular to the auger axis that also includes the generally rectangular plate's dimension of elongation. The dimensions of the generally rectangular plate are selected, and the hexagonal through bore through the center of the generally rectangular plate is formed at a rotational orientation with respect to the hexagonal shaft 148D and generally triangular front portion of the hub, so that one corner of the generally rectangular plate is generally even with the upper edge of one corner of the generally triangular hub plate and the diagonally opposing corner of the generally rectangular plate is generally even with the bottom edge of the opposite corner (along the same edge as the first corner) of the generally triangular hub plate. This results in the other two opposing corners of the rectangular plate (only one of which is shown in FIG. 24) being above/below the respective flat upper and lower (triangular) surfaces of the generally triangular hub plate. A respective through hole 148E (only one of which is shown in FIG. 24) with an axis generally parallel to the auger axis 16 (FIG. 1) passes through these two corners.
[0125] Cutting head 176 also includes first steel yoke 149A and second steel yoke 149B. First yoke 149A includes a pair of elongated arms 150A, 150B that are offset from each other by a base portion 150C that extends between the arms. A through hole 151C extends through arm 150A, while a concentric through hole 151D extends through arm 150B. Similarly, second yoke 149B include a pair of elongated arms 152A, 152B that are offset from each other by a base portion 152C that extends between the arms. A through hole 151A extends through member 152A, while a concentric hole 151B extends through arm 152B. First yoke 149A is positioned with respect to hub 148B so that its arm 150A abuts the side of the generally rectangular hub portion opposite the generally triangular hub portion and so that hole 151D is concentrically aligned with a through hole (not shown in FIG. 24) through the corner of the generally rectangular hub plate opposite the corner through which through hole 148E passes (with a center axis parallel to the center axis of through hole 148E), and so that its arm 150B abuts the side of the generally rectangular hub plate adjacent the generally triangular hub plate and so that hole 151C is concentrically aligned with the through hole through the rectangular hub plate corner. An elongated bolt or other suitable fastener 154 is received through through-hole 151D, the through-hole through the corner of the generally rectangular hub plate (not shown in FIG. 24), and through hole 151C and is secured in its position with respect to the yoke and the hub by a threaded nut 153 that threads onto a threaded distal end of bolt 154. The gap between arms 150A and 150B is wider than the width of the generally rectangular plate of hub 148B received between the yoke arms. As a result, first yoke 149A is pivotable with respect to the generally rectangular hub portion freely about the axis of the through-hole through the corner of the generally rectangular hub portion (not visible in FIG. 24) and is, therefore, pivotable with respect to the hub, generally. However, because arm 150B engages the generally planar, triangular face of the triangular hub portion (the face being opposite the face visible in FIG. 24) both in an extended position of the yoke, when the edge of the yoke opposite the distal ends of arms 150A and 150B extends beyond the lateral edge of the hub (with respect to the auger axis), and in a retracted position of the yoke, when the edge of the yoke opposite the distal ends of arms 150A and 150B abuts the face of the generally triangular portion of the hub in the central portion of that plate, the yoke is pivotable about the axis of the through-hole through the corner of the generally rectangular hub plate (not visible in FIG. 24) only over an approximately 180 arc, between the yoke's extended and retracted positions. Second yoke 149B is pivotally attached to the diagonally opposite corner of the rectangular hub portion, about through hole 148E, in the same manner, so that yoke 149B is pivotably attached to the cutting head hub between extended and retracted positions over a 1800 arc. When the yokes are in their extended positions, their distal ends define the outermost cutting range of the cutting head as measured radially from the auger axis. When they are in their retracted positions, they are entirely at or inside the radially outermost (from the auger axis) edge of the cutting head hub 148B.
[0126] Referring to FIG. 23, a plurality of cutting bits 155 (in this instance, wing cutters, which may be formed of various materials, such as steel, carbide, or industrial diamond) are attached to the cutting head, for example at a plurality of attachment posts 148A that extend in the forward direction (to the left in the perspective of FIG. 1), parallel to auger axis 16 (FIG. 1), from the forward faces of the central triangular plate of cutting head hub 148B and from the forward faces of arm 150B and arm 151B of yokes 149A and 149B. Each cutting bit is secured onto its post by a pair of bolts that thread into corresponding threaded holes in the posts, thereby aligning each cutting bit so that its tip 155A is oriented in a predetermined direction. In one or more embodiments, each cutting bit defines a bladed end that forms its tip 155A at the apex of two side blades. At each cutting bit, the tip 155A, and the blade edges to each side of the tip, face in a direction generally perpendicular to the auger's elongation dimension 16 (FIG. 1). The cutting bits are oriented, on the triangular plate and on the two yokes 149A and 149B when the yokes are rotated on the hub to their extended positions, so that the blades and the tip face in generally the same direction (though, as apparent in FIG. 23, with some variation accommodated) and so that the blades/tips of the cutting bits on the hub/yokes on one side of the auger center axis face in a direction generally opposite of the blades/tips of the cutting bits on the other side of the auger center axis. Thus, as the cutting head rotates about that axis, all of the cutting head tips/blades either face in the cutting head's direction of rotation or opposite to the cutting head's direction of rotation, depending on that rotational direction, and in one or more embodiments, all of the cutting bits are oriented on the cutting head so that their tips/blades face in the same cutting head rotational direction. In one or more embodiments, for example, the auger machine rotates cutting head 176 counterclockwise (in the perspective illustrated in FIG. 23), and tips 155A face into that counterclockwise rotation so that they are the leading component (followed by blade edges) of cutting bits 155 that contact underground material as the auger machine pushes the auger and its cutting head into the bore face. Further, the posts are disposed on the hub/yokes so that the cutting bits are the leading components of the cutting head as it is pushed into the bore face, so that the cutting bits, and particularly their tips/blades, do the primary work of dislodging earth and rock from the bore face.
[0127] The cutting bits as illustrated in FIGS. 23-25, at 155, are one example of cutting bits that may be employed in a cutting head as disclosed herein, but other cutting bits may be utilized, and are utilized, in one or more other embodiments, and, for example, may have cutting configurations different from the tips and side blade edges illustrated in those figures, such as carbide-tipped cutters, roller cones, disc cutters, diamond cutters, etc. In the one or more embodiments illustrated in FIGS. 23-25, the cutting bits may be exchanged with new cutting bits by removing the bolts that hold the bits on the cutting head hub, removing the cutting bits from the respective posts, replacing the cutting bits on the posts with new cutting bits having a two-bolt hole configuration like the original cutting bits, and securing the new cutting bits onto the posts with the same bolts. Cutting bits may be exchanged, for example, to implement new, unworn bits of the same type or, instead, cutting bits of a different type that may be, for example, more effective in an earth or rock formation that may be newly encountered during excavation of the bore. To exchange the cutting bits, the auger machine first rotates the auger in the directional rotation (clockwise, in the perspective as in FIG. 23) opposite the normal rotational direction when the cutting bit is being used to cut into the bore face. This causes the yokes to rotate back to their retracted positions. With the maximum perimeter of the cutting head now smaller than/within the inner diameter of the steering head interior body, the auger machine moves rearward in its pit, thereby pulling the auger rearward and the cutting head into and through the steering head auger interior body 23 (FIG. 1). When the auger machine pulls the rearmost auger section into the starting pit, the machine is stopped, and that auger section is detached both from the auger machine and the immediately forward auger section. The auger machine is moved forward in the pit, reattached to the now-rearmost auger section, and the process is repeated until the forwardmost auger section, with the cutting head, is removed from the bore into the pit. The operator replaces the cutting bits, as described above, and then uses the auger machine to push the first auger section, with the new cutting bits on the cutting head, back into the bore. Upon inserting the first auger section, the operator detaches the first auger section from the auger machine, moves the auger machine rearward in the starting pit, attaches the next auger section to the auger machine and the first auger section, and pushes the auger further into the bore. This process is repeated until the first auger section, led by the cutting head, is pushed back through the steering head and the cutting head again engages the bore face. In other embodiments, cutting bits 155 are integrally attached to central body 148 and yokes 149A, 149B, either to the triangular plate and yoke arms directly or through integral attachment, such as by welds, to attachment posts 148A.
[0128] While two yokes 149A, 149B are illustrated in the embodiment of FIG. 23, a different number of cutting bits may be utilized in other embodiments. As discussed above, the pivotable attachment between cutting bit yokes 149A, 149B and central body 148 allows each yoke to be pivotable between an extended position and a retracted position. In the extended position, the distal ends of yokes 149A, 149B are at their radially outermost position relative to a central rotational axis of the auger (e.g., axis 16 of FIG. 1). In the retracted position, the distal ends of yokes 149A, 149B are at their radially innermost positions relative to the central rotational axis. In the arrangement of the embodiments discussed herein with regard to FIGS. 23-24, each yoke is pivotal from its retracted position to its extended position with respect to the cutting head hub about an axis parallel to the auger's center rotational axis in the rotational direction (projected into a plane perpendicular to the auger's and the yoke's rotational axis) opposite to the cutting head's rotational direction when the auger rotates the cutting head in its cutting direction, that is, as discussed above, the direction that drives the cutting bits' points into the earth or rock and the auger blade to push the resulting earth and rock debris rearward. For example, each of yokes 149A, 149B is pivotal about the axis of its bolt 154 from its retracted position to its extended position in the clockwise direction (in the perspective illustrated in FIG. 23). As discussed above, to use the cutting head to cut into the bore face, the auger machine rotates the auger counterclockwise (again, in the perspective illustrated in FIG. 23). If, when the auger machine begins such a counterclockwise rotation, the yokes are in their retracted positions and the auger machine has pushed the face of the cutting head into the bore face so that the cutting bits engage the earth and/or rock thereof, the mechanical interaction (such as friction or abutting engagement) between the bore face and the cutting bits attached to the yokes resists the yokes' movement with the cutting head hub that the hub's rotation with the auger would otherwise encourage. This resistance causes the yokes to rotate with respect to the cutting head hub about their respective bolts 154, in a clockwise direction as the cutting head hub rotates in a counterclockwise (in this instance, cutting) direction. As the cutting head hub continues to rotate counterclockwise, and the yokes thereby continue to rotate in the clockwise direction with respect to the hub, the yokes eventually reach their fully extended positions, at which yoke arms 150B and 151B respectively come into abutment with the opposing flat faces of the hub's triangular plate. This engagement forms a stop that precludes the yokes' further clockwise (with respect to the hub) rotation and brings the orientation of the cutting bits 155 of yokes 149A and 149B into alignment with the cutting bits mounted on the triangular plate of the hub on their side of the central rotation axis, so that all cutting bits on the cutting head face into the direction of the cutting heads' rotation, as discussed above, and so that the outermost cutting bit, or other cutting structure, on the two yokes defines the diameter of the bore cut by the cutting head.
[0129] With the yokes in their extended positions, the cutting head's outer diameter is larger than the inner diameter of the steering head interior body 23 (FIG. 1), and the cutting head, therefore, cannot be retracted back through the steering head interior body to, for example, exchange the cutting bits. To return the yokes to their retracted positions, the operator reverses the auger's rotational direction while the cutting head remains engaged with the bore face. As the cutting head hub starts now to rotate in the clockwise direction (in the perspective of FIG. 23), the engagement between the cutting bits on the yokes and the bore face earth or rock resists the yokes' movement with the cutting head hub while remaining in their fully extended positions, and the yokes begin to rotate in the counterclockwise direction with respect to the cutting head hub about the yokes' respective bolts 154. As the cutting head continues to rotate in the clockwise direction, the yokes continue to rotate in the counterclockwise direction with respect to the cutting head hub, until the other sides of yoke arms 150B and 151B engage the flat faces of the cutting head hub's triangular plate. At this point, the yokes are in their fully retracted positions, and the outer diameter of the cutting head is now shorter than the inner diameter of the steering head interior body, and the cutting head can now be retracted back through the steering head and remainder of the bore to replace the cutting bits, as discussed above.
[0130] FIG. 25 is a perspective view illustrating cutting head 176 attached to a forwardmost auger section extending through a steering head 10 (FIG. 1). As discussed with respect to FIG. 1, steering head 10 comprises a first outer tube 71 and a lead end 92. Forwardmost auger section 112 is also received within steering head 10, and auger section 12 is attached to cutting head 176 so that auger 112 and cutting head 176 are rotationally fixed to each other so that they rotate together about auger rotational axis 16 (FIG. 1). In FIG. 25, first yoke 149A is illustrated between a fully retracted position and a fully extended position. However, second yoke 149B is illustrated in a fully extended position.
[0131] FIGS. 26 and 27 schematically illustrate the operation of cutting head 176. FIG. 26 illustrates a cutting head 176 with its yokes pivoted to their retracted positions so that the cutting head may be moved axially through the internal volume of the steering head interior body, and FIG. 27 illustrates cutting head 176 of FIG. 26 with cutting bit yokes pivoted to their extended positions so that the cutting head has a greater effective cutting area than when the yokes are retracted but cannot pass through the steering head interior body's internal volume.
[0132] As illustrated in FIG. 26, cutting head 176 has a reduced cutting area diameter when yokes 149A, 149B are in their retracted positions, so that cutting head 176 may be moved through interior volume 125 of interior body 23. Steering head interior body 23 interior volume 125 generally defines a diameter A in a plane perpendicular to the auger rotational axis 16, while cutting head 176 generally defines a maximum width B1 (over all planes perpendicular to axis 16 encompassing the length of the cutting head) when the yokes are in their retracted states, where maximum width B1 is smaller than diameter A. However, as illustrated in FIG. 27, cutting head 176 may have an enlarged cutting area when the yokes are in their radially outward extended positions, so that cutting head 176 may not be retracted into the inner volume of the steering head interior body. Cutting head 176 generally defines a maximum width B2 over the planes perpendicular to auger axis 16 when the yokes are in their extended positions, and maximum width B2 is greater than diameter A so that cutting head 176 may not be moved through interior volume 125 of interior body 23 when in that state. Maximum width B2 of cutting head 176 is greater than a maximum diameter D5 of the steering head's first outer tube 71 (thereby defining the steering head's maximum outer perimeter). In such embodiments, the extension of the yokes to their extended positions allows cutting head 176 to cut a sufficiently large enough excavation bore to facilitate the steering head's movement into and through the excavation tunnel. As discussed above, in one or more embodiments, rotation of cutting head 176 about axis 16 in a first rotational direction R1 as illustrated in FIG. 26 may cause yokes 149A, 149B to move to their fully retracted positions, while rotation of cutting head 176 about axis 16 in a second rotational direction R2, opposite rotational direction R1, as illustrated in FIG. 27 may cause yokes 149A, 149B to move to their expanded positions. In moving between the retracted position and the expanded position, yoke 149A rotates about axis A3, and yoke 149B rotates about axis A2. Rotational direction R2, in one or more embodiment, is the auger's rotational direction when the cutting head is cutting into the bore face and the auger blade is moving material dislodged by the cutting head from a lead end of the steering head to the rear end of a steering head (and rearward therefrom, to the auger machine's starting pit).
[0133] While cutting bits 155, as described in example embodiments above, are pivotably attached to a central body 148 (through their attachments to the pivoting yokes 149A and 149B), in other embodiments cutting bits are non-pivotally attached to the cutting head's central body. For example, and referring to FIG. 28, an example cutting bit 209 comprises an attachment bracket 209C that attaches to the cutting head hub main body by welding and a body 209B integrally fixed to the bracket. Body 209B generally defines a spherical shape with a plurality of cutting protrusions 209A positioned at various spaced-apart locations on body 209B. Cutting protrusions 209A generally define a conical shape with rounded carbide tips. However, it should be understood that cutting bit 209 is merely one example of many different types of cutting bits that may be utilized. Other cutting bits may be provided having different shapes and sizes.
[0134] But in still further embodiments, cutting bits other than wing cutters, such as cutting bits 209, are pivotally attached to the cutting head's central body. Referring to FIGS. 29 and 30, for example, cutting head 176 has a hub with a main body 148 having a maximum radial dimension (in a plane perpendicular to the auger axis, e.g. 16 in FIG. 1) that is less than the radial dimension (in the same plane from the steering head interior body axis) of the inner surface of steering head interior body 23 (FIG. 1). The cutting head has a plurality of cutting bits 209 (see also FIG. 28) that are disposed in fixed positions on the cutting head main body, on a steel lower collar 148C and a steel upper collar 1481, each of which is welded or otherwise fixedly attached to a central shaft 148H. Each of collars 148C and 1481 has a central through-hole through which central shaft 148H passes. A steel top disc 210 is bolted to the upper surface of upper collar 1481 so that those components are fixed to each other. Top disc 210 defines three slots that respectively receive brackets 209C (FIG. 28) of the cutting bits 209 which are, in turn, bolted or welded onto top disc 210. Lower collar 148C has an annular center section that surrounds center shaft 148H and three flanges 214 that extend radially outward from the annular center section. Each flange defines a through hole 211 (only one of which is shown, in FIG. 29) having a center axis parallel to the axis of elongation of center shaft 148H. A respective cutting bit 209 is attached to two of these flanges by a respective bolt that extends into the respective flange 214 or by welding.
[0135] Other cutting bits 209, however, are disposed pivotally on main body 148 so that the bits are pivotable between a first, retracted, position with respect to the main body so that the cutting bits do not extend radially outward of the cutting head's maximum radial dimension and a second, extended, position in which the cutting bit does extend radially outward of the cutting head's maximum radial dimension. With the one or more pivotable cutting bits in their extended positions, the cutting head cuts a bore through the rock and earth of a diameter (in a plane perpendicular to the auger axis) that is at least large enough to encompass the steering head's maximum periphery and, in one or more embodiments, that is larger than needed to encompass that periphery. With the one or more pivotable cutting bits in their retracted positions, however, the maximum periphery of the cutting head in a plane perpendicular to the auger axis is within the inner diameter of the steering head interior body, thereby allowing the auger boring machine to retract the auger, including the cutting head, from the steering head interior body, as described above.
[0136] Referring again to FIGS. 29 and 30, cutting head 176 has a hub comprising steel central body 148 built upon, for example, a generally cylindrical steel lower central shaft 148D, the rear end of which defines a hexagonal central bore opening (not shown) that receives a correspondingly hexagonal extension portion (see 112C, FIG. 14) of the steering head auger body of the forwardmost auger section 112A (FIG. 1), thereby rotationally locking cutting head 176 to that forwardmost auger section due to engagement between the flat surfaces of the hexagonal bore and the flat surfaces of the hexagonal extension portion. Thus, when the auger machine rotates the auger in either rotational direction, the auger machine correspondingly rotates the cutting head. The cutting head is also secured to the forwardmost auger section in the axial direction by a pin (not shown) that extends radially through the auger section's central body and generally cylindrical (with hex bore) shaft 148D at a through hole 213. In the steering head's operation, the auger is pushed forward by the auger machine, so that the cutting head is pushed into the front face of the bore. The cutting head's rearward axial movement with respect to the central auger body is precluded in such circumstances by the pin and/or by the rear face of shaft 148D that abuts a shoulder of the central auger body.
[0137] Cutting head 176 also includes first steel pivot arm 149A, second steel pivot arm 149B, and third steel pivot arm 149C that abut respective radial flanges 214 on lower collar 148C. A respective through hole (not shown) extends through each pivot arm and is aligned with the hole 211 extending through the pivot arm's corresponding lower collar flange 214. A respective elongated bolt passes through each through-hole 211 and the corresponding pivot arm through hole to secure each pivot arm 149A, 149B, and 149C to its lower collar radial flange 214. The bolts fit loosely within the through holes, thus allowing the pivot arms to rotate with respect to their corresponding lower collar radial flanges about their respective bolts. Three lower radial flanges 215 are fixedly attached to (e.g., by welding) and extend radially outward from central shaft 148H. The three flanges 215 are spaced evenly apart around the circumference of central shaft 148H and extend below respective radial flanges 214. For ease of explanation, only one lower radial flange 215 is illustrated in FIGS. 29-32, but it should be understood that three are provided in the embodiments illustrated in these figures. A through hole extends through the distal end of each lower radial flange 215 and is aligned with the through hole of its corresponding pivot arm and through hole 211. Each lower radial flange 215 is spaced from its corresponding radial flange 214 by a distance slightly larger than the thickness (in the dimension extending between flanges 214 and 215) of its corresponding pivot arm 149A, 149B or 149C, thereby facilitating the pivot arm's ability to pivot with respect to both flanges 214 and 215. The bolt that passes through the through-holes of flange 214 and the pivot arm also passes through the through hole of the lower radial flange. A nut attached at the end of the bolt beneath the lower flange 215 secures the assembly, without creating a friction fit between pivot arms 149A, 149B, and 149C and either their corresponding flanges 214 or 215.
[0138] Each bracket 209C (FIG. 28) of the cutting bits 209 respectively attached at the distal ends of pivot arms 149A, 149B, and 149C has a generally planar face that is closely adjacent to, but that does not touch, an opposing generally planar end face of its corresponding lower radial flange 214. To allow the pivot arm and cutting bit to pivot about the through hole axis of lower radial flange 214, the corners of the distal ends of the lower radial flanges are chamfered, thereby allowing the generally planar face of the bracket of the respective cutting head to clear the distal end of its corresponding lower radial flange. Extending upward from the right edge of each lower radial flange 215 (from the perspective of an observer located along the center axis of generally cylindrical central shaft 148H, looking radially outward through the lower radial flange), however, is a generally planar stop flange 216 (only one of the three of such stop flanges being shown in the figures) that blocks rotation of its corresponding pivot arm 149 in the direction of the stop flange. The pivot arm, therefore, can pivot only in the opposite rotational direction. That rotation, after an approximately 90 pivot, is blocked by engagement of the leading edge of the pivot arm 149A, 149B, or 149C, as the case may be, with the outer surface of central shaft 148H. Thus, each pivot arm 149A, 149B, or 149C is pivotable about the axis of the through-hole through that pivot arm (and the adjacent through holes through the upper and lower radial flanges 214 and 215) only over an approximately 90 arc, between the pivot arm's extended and retracted positions. When the pivot arms are in their extended positions, their distal ends (and/or the radially outermost ends of the respective cutting bits attached to them) define the outermost cutting range of the cutting head as measured radially from the auger axis. When they are in their retracted positions, they are entirely at or inside a perimeter about the auger axis that is within, or at most at, a perimeter defined by the inner wall surface of steering head interior body 23 (FIG. 1). FIGS. 29 and 30 illustrate the pivoting cutting bits in their extracted positions, while FIGS. 31 and 32 illustrate the pivoting cutting bits in their retracted positions.
[0139] In one or more embodiments, the auger machine rotates cutting head 176 counterclockwise (in the perspective of an observer in the auger's center axis, looking down onto the top of the cutting head, in FIG. 29) when cutting head 176 engages underground material as the auger machine pushes the auger and its cutting head into the bore face. The cutting bits are disposed on their brackets and the pivot arms/radial flanges or otherwise on cutting head main body 148 so that the cutting bit bodies 209B and cutting protrusions 209A are the leading components of the cutting head as it is pushed into the bore face, so that the cutting bits, and particularly their cutting protrusions, do the primary work of dislodging earth and rock from the bore face.
[0140] To exchange the cutting bits, the auger machine first rotates the auger in the directional rotation (clockwise, looking down onto the cutting head in the perspective as in FIG. 29) opposite the normal rotational direction when the cutting bit is being used to cut into the bore face. This causes the pivot arms 149A, 149B, and 149C to rotate back to their retracted positions, as discussed below. With the maximum perimeter of the cutting head now smaller than/within the inner diameter of the steering head interior body, the auger machine moves rearward in its pit, thereby pulling the auger rearward and the cutting head into and through the steering head auger interior body 23 (FIG. 1). When the auger machine pulls the rearmost auger section into the starting pit, the machine is stopped, and that auger section is detached both from the auger machine and the immediately forward auger section. The auger machine is moved forward in the pit, reattached to the now-rearmost auger section, and the process is repeated until the forwardmost auger section, with the cutting head, is removed from the bore into the pit. The operator replaces the cutting bits and then uses the auger machine to push the first auger section, with the new cutting bits on the cutting head, back into the bore. Upon inserting the first auger section, the operator detaches the first auger section from the auger machine, moves the auger machine rearward in the starting pit, attaches the next auger section to the auger machine and to the first auger section, and pushes the auger further into the bore. This process is repeated until the first auger section, led by the cutting head, is pushed back through the steering head and the cutting head again engages the bore face.
[0141] As discussed above, the pivotable attachment between cutting bit pivot arms 149A, 149B, 149C and central body 148 allows each pivot arm to be pivotable between an extended position and a retracted position. In the extended position, the distal ends of pivot arms 149A, 149B, 149C are at their radially outermost position relative to a central rotational axis of the auger (e.g., axis 16 of FIG. 1). In the retracted position, the distal ends of pivot arms 149A, 149B, 149C are at their radially innermost positions relative to the central rotational axis. In the arrangement of the embodiments discussed herein with regard to FIGS. 29-32, each pivot arm is pivotal from its retracted position to its extended position with respect to the cutting head body about an axis parallel to the auger's center rotational axis in the rotational direction opposite to the cutting head's rotational direction when the auger rotates the cutting head in its cutting direction, that is, as discussed above, the direction that drives the cutting bits' cutting protrusions 209A into the earth or rock and the auger blade to push the resulting earth and rock debris rearward. For example, each of pivot arms 149A, 149B, 149C is pivotal about the axis of its bolt (that connects it to its radial flanges 214 and 215) from its retracted position to its extended position in the clockwise direction (looking down onto the cutting head, in the perspective illustrated in FIG. 29). As discussed above, to use the cutting head to cut into the bore face, the auger machine rotates the auger counterclockwise (again, looking down onto the cutting head, in the perspective illustrated in FIG. 29). If, when the auger machine begins such a counterclockwise rotation, the pivot arms are in their retracted positions and the auger machine has pushed the face of the cutting head into the bore face so that the cutting bits engage the earth and/or rock thereof, the mechanical interaction (such as friction or abutting engagement) between the bore face and the cutting bits attached to the pivot arms resists the pivot arms' movement with the cutting head hub that the hub's rotation with the auger would otherwise encourage. This resistance causes the pivot arms to rotate with respect to the cutting head hub about their respective bolts, in a clockwise direction as the cutting head hub rotates in a counterclockwise (in this instance, cutting) direction. As the cutting head hub continues to rotate counterclockwise, and the pivot arms thereby continue to rotate in the clockwise direction with respect to the hub, the pivot arms eventually reach their fully extended positions, at which pivot arms come into abutment with their corresponding generally planar stop flanges 216. This engagement forms a stop that precludes the pivot arms' further clockwise rotation with respect to the hub and orients cutting bits 209 of pivot arms 149A, 149B, 149C so that the radially outermost cutting protrusions on the three pivot arms defines the diameter of the bore cut by the cutting head.
[0142] With the pivot arms in their extended positions, the cutting head's outer diameter is larger than the inner diameter of the steering head interior body 23 (FIG. 1), and the cutting head, therefore, cannot be retracted back through the steering head interior body to, for example, exchange the cutting bits. To return the pivot arms to their retracted positions, the operator reverses the auger's rotational direction while the cutting head remains engaged with the bore face. As the cutting head hub starts now to rotate in the clockwise direction (looking down onto the cutting head, in the perspective of FIG. 29), the engagement between the cutting bits on the pivot arms and the bore face earth or rock resists the pivot arms' movement with the cutting head hub while remaining in their fully extended positions, and the pivot arms begin to rotate in the counterclockwise direction about their bolts. As the cutting head continues to rotate in the clockwise direction, the pivot arms continue to rotate in the counterclockwise direction, until the other sides of pivot arm arms 149A, 149B, 149C engage the hub's central shaft 148H. At this point, the pivot arms are in their fully retracted positions, and the outer diameter of the cutting head is now shorter than the inner diameter of the steering head interior body, and the cutting head can now be retracted back through the steering head and remainder of the bore to replace the cutting bits, as discussed above.
[0143] Referring to FIG. 33, an example block diagram is illustrated showing various components of a system 158 comprising a steering head 10. Steering head 10 comprises one or more light assemblies 159, which may be similar to light assembly 142 of FIG. 19 and FIGS. 20-22, and light assemblies 159 may comprise a sensor similar to sensor 146 of FIGS. 20-22. Steering head 10 also comprises one or more steering flaps 50, a communication interface 160, one or more processors 161, and one or more memory devices 162. Auger machine 11 comprises a communication interface 163, one or more processors 164, and one or more memory devices 165. External control station 14 comprises a communication interface 166, one or more processors 168, and one or more memory devices 169. System 158 also includes one or more fluid reservoirs 115 (e.g., respectively for water, bentonite, and hydraulic fluid) and one or more fluid pumps 147 for respectively pumping fluid from the reservoirs.
[0144] External control station 114 may be configured to control the operation of steering head 10 in some embodiments. For example, external control station 114 may cause steering flaps 50 to be extended or retracted by altering an amount of hydraulic fluid provided from a hydraulic fluid reservoir 115 via a pump 147. As another example, external control station 114 may alter the amount of cooling fluid that is provided to steering head 10 by a pump 147 and reservoir 115 to adjust the rate of cooling. As another example, external control station 114 may alter the amount of lubricating fluid that may be provided to steering head 10 by a pump 147 from a reservoir 115 to adjust the amount of lubricant (e.g., bentonite) that is provided. External control station 114 may also be configured to adjust the amount of rotation or power generated at auger machine 11 so that the amount and/or direction of rotation of an auger within steering head 10 may be adjusted. However, external control station 114 may also control operation of steering head 10 and other components of system 158 in other ways as well.
[0145] Auger machine 11 may be configured to generate rotation of an auger within steering head 10. Auger machine 11 may be removably attached to any auger within steering head 10 to allow for further auger portions to be added to any existing augers, thereby extending the overall length of the auger. In some embodiments, auger machine 11 may be adjusted so that the direction of rotation may be changed or so that the rotational speed is changed.
[0146] Processor(s) 161, 164, 168 may be any means configured to execute various programmed operations or instructions stored in a memory device (e.g., memory devices 162, 165, 169) such as a device or circuitry operating in accordance with software or otherwise embodied in hardware or a combination of hardware and software (e.g. a processor operating under software control or the processor embodied as an application specific integrated circuit (ASIC) or field programmable gate array (FPGA) specifically configured to perform the operations described herein, or a combination thereof) thereby configuring the device or circuitry to perform the corresponding functions of processor(s) 161, 164, 168 as described herein.
[0147] In an example embodiment, memory devices 162, 165, 169 may include one or more non-transitory storage or memory devices such as, for example, volatile and/or non-volatile memory that may be either fixed or removable. Memory devices 162, 164, 168 may be configured to store instructions, computer program code, and additional data in a non-transitory computer readable medium for use, such as by processor(s) 161, 164, 168 for enabling the components of system 158 to carry out various functions in accordance with example embodiments of the present invention. For example, memory devices 162, 165, 169 may be configured to buffer input data for processing by processor(s) 161, 164, 168. Additionally, or alternatively, memory devices 162, 165, 169 could be configured to store instructions for execution by processor(s) 161, 164, 168. Memory devices 162, 165, 169 may include computer program code that is configured to, when executed, cause processor(s) 161, 164, 168 to perform various methods described herein. Memory devices 162, 165, 169 may serve as non-transitory computer readable mediums having stored thereon software instructions that, when executed by one or more processors, cause methods described herein to be performed.
[0148] Communications interfaces 160, 163, 166 may be configured to enable communication to other components of system 158 (e.g. via an external network). Communications interfaces 160, 163, 166 may also include one or more communications modules configured to communicate with one another in any of a number of different manners including, for example, via a network. In this regard, communications interfaces 160, 163, 166 may include any of a number of different communication backbones or frameworks including, for example, Ethernet, global positioning system (GPS), cellular, Wi-Fi, or other suitable networks. The network may also support other data sources, including GPS. In this regard, numerous other peripheral devices may be included in system 158. In some embodiments, some or all of communications interfaces 160, 163, 166, may be configured to communicate using short-range wireless technologies such as Bluetooth (e.g., Bluetooth Version 4.1 or another version), Wi-Fi, NearLink, near-field communication (NFC), low power wide area networks (LPWAN), ultra-wideband (UWB), wireless local area network (WLAN) in accordance with IEEE 802.11(b), IEEE 802.11(g), and/or IEEE 802.11(n) standards, and/or low-rate wireless personal access networks (LR-WPAN) pursuant to the IEEE 802.15.4 standard.
[0149] Connections between various components may be wireless connections as noted above. However, in some embodiments, the connections may be wired or direct connections. While certain devices are illustrated in system 158 of FIG. 33, it should be understood that additional devices or components may be added to system 158 and that some of the illustrated devices or components of system 158 may be omitted in some embodiments.
[0150] Additionally, as additional pipe casing sections or extraction tube sections are added, each added section may have an auger received within an internal volume therein, extending the overall length of the augers. For example, FIG. 34 illustrates an example method 170 for adding additional augers. At operation 171, rotation of existing augers may be stopped. This may be done by turning off an auger machine or by otherwise causing auger machine to stop any rotation. At operation 172, existing augers may be disassembled from the auger machine. This may be done by disassembling the auger most proximate to the auger machine from the auger machine. However, other portions of the existing augers may be disassembled as well. At operation 173, the auger machine may be moved farther away from the auger most proximate to the auger machine, and this may enable more space to be provided so that an additional auger may be attached. At operation 174, a new auger may be assembled to existing augers and to the auger machine. A first end of the new auger may be attached to the existing augers, and a second end of the new auger may be attached to the auger machine. At operation 175, the existing auger(s) and new auger may be rotated again. This may be done by turning the auger machine back on to generate rotation of both the preexisting auger and the newly introduced auger.
[0151] Method 170 of FIG. 34 is merely exemplary, and various operations of method 170 may be modified in various ways. Additional operations may be added to method 170 in other embodiments, and some operations of method 170 may be omitted in some embodiments. Additionally, operations of method 170 may be performed in different orders, and some operations of method 170 may be performed simultaneously.
[0152] While one or more preferred embodiments of the invention are described above, it should be appreciated by those skilled in the art that various modifications and variations may be made in the present invention without departing from the scope and spirit thereof. For example, alternate embodiments of composite panels in accordance with the present disclosure may have fewer, or more, layers than the number of the discussed embodiments. It is intended that the present invention cover such modifications and variations as come within the scope and spirit of the appended claims and their equivalents.
CONCLUSION
[0153] Many modifications and other embodiments set forth herein will come to mind to one skilled in the art to which these embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the embodiments are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the invention. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions may be provided by alternative embodiments without departing from the scope of the invention. In this regard, for example, different combinations of elements and/or functions than those explicitly described above are also contemplated within the scope of the invention. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
