Drill head for creating a borehole in the ground

Abstract

A drill head for creating a substantially vertical borehole in the ground, includes a body connected to a rotational drive of a drilling device; drilling tools on the body, for loosening the ground at a working face of the borehole; suctioning elements for leading away the loosened ground, which can be connected to a pump, and the suctioning elements include an opening region on the body and with at least one opening in the region of the drilling tools. The opening region has may have an elongate extent, and is connected to a suction box with an opening for connecting to the pump. The loosened ground can be sucked through the opening into the suction box with the pump. The suction box is tapered in width from the opening toward the connection opening, and that the height of the suction box increases from the opening toward the connection opening.

Claims

1. A drill head, for creating a vertical borehole in the ground, comprising a body connectable to a rotary drive of a drilling device, wherein the body comprises; drilling tools for loosening the ground at a face of the borehole; a suction system, for discharging the loosened ground at the face, connectable to a pump, wherein the suction system has an opening region disposed on the body comprising at least one opening in a section of the drilling tools at the face, wherein: the opening region is elongated; the at least one opening of the opening region is connected to a suction box which at an end opposite to the opening has a connector opening for connecting to the pump; the suction box comprises a first pair of opposite sides and a second pair of opposite sides, with a separation between the first pair of opposite sides increasing and a separation of a second pair decreasing between the opening and the connector opening, the ground loosened by the drilling tools in a flow direction is suctioned in the opening region through the opening and into the suction box by the pump; wherein the suction box is disposed vertically.

2. The drill head as claimed in claim 1, wherein the suction box comprises a nozzle assembly which is directed from the opening toward the connector opening.

3. The drill head as claimed in claim 1, wherein the opening comprises a slot.

4. The drill head as claimed in claim 1, comprising nozzles which are directed into the at least one opening.

5. The drill head as claimed in claim 1, comprising at least two nozzles for dispensing a jet of a medium disposed in front of the opening relative to the direction of drill head rotation, on the lower side of the drill head, said nozzles being directed toward the face.

6. The drill head as claimed in claim 1, comprising at least two nozzles for dispensing a jet of a medium disposed behind the opening relative to the direction of drill head rotation, on the lower side of the drill head, said nozzles being directed toward the face.

7. The drill head as claimed in claim 1, comprising at least one nozzle for dispensing a jet of a medium provided on the lower side of the drill head, wherein the jet moves the loosened ground into a region of the face traversed by the opening during the rotation of the drill head.

8. The drill head as claimed in claim 7, comprising a baffle on the lower side of the drill head, wherein the baffle is disposed as one of a straight or curved element on the lower side of the drill head disposed, at least one of diagonal or at least partially circumferential, wherein the at least one nozzle jet hits the baffle, resulting in a change in the moving direction of the loosened ground.

9. The drill head as claimed in claim 1, comprising at least two nozzles in the center of the lower side of the drill head aligned in opposing directions.

10. The drill head as claimed in claim 1, comprising at least two nozzles tangentially aligned on the lower side of the drill head.

11. The drill head as claimed in claim 1 comprising radially adjustable peripheral cutting tools.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be explained in more detail hereunder by means of exemplary embodiments in conjunction with a drawing. In the drawing:

(2) FIGS. 1 to 11 show views and details pertaining to a first embodiment of a drill head according to the invention;

(3) FIGS. 12 to 19 show views and details pertaining to a second embodiment of a drill head according to the invention; and

(4) FIGS. 20 to 32 show views and details pertaining to a third embodiment of a drill head according to the invention.

(5) In the figures pertaining to the first embodiment: FIG. 1 shows a three-dimensional view of the lower side of the drill head of the first embodiment according to the invention; FIG. 2 shows a lateral view of FIG. 1; FIG. 3 shows a plan view of the lower side of FIG. 1; FIG. 4 shows a plan view of the upper side of FIG. 1; FIG. 5 shows a three-dimensional view of a first embodiment of a suction box according to the invention; FIG. 6 shows a front view of FIG. 5; FIG. 7 shows a lower view of FIG. 5; FIG. 8 shows a three-dimensional illustration of the lower view of FIG. 7; FIG. 9 shows a partially sectional lateral view of FIG. 5, having a deployed cleaning element; FIG. 10 shows a view analogous to that of FIG. 9, having a retracted cleaning element; FIG. 11 shows a three-dimensional downward-tilted front view of FIG. 5.

(6) In the figures pertaining to the second embodiment: FIG. 12 shows a three-dimensional view of the lower side of the drill head of the second embodiment according to the invention; FIG. 13 shows a lateral view of FIG. 12; FIG. 14 shows a plan view of the lower side of FIG. 12; FIG. 15 shows a plan view of the upper side of FIG. 12; FIG. 16 shows a plan view of a second embodiment of a suction box according to the invention; FIG. 17 shows a lower view of FIG. 16; FIG. 18 shows a partially sectional side view of FIG. 16 along the line A-A; FIG. 19 shows an enlarged fragment of FIG. 18.

(7) In the figures pertaining to the third embodiment: FIG. 20 shows a plan view of the lower side of the drill head of the third embodiment according to the invention; FIG. 21 shows a plan view of the upper side of FIG. 12; FIG. 22 shows FIG. 20 having material conveying regions illustrated; FIG. 23a shows FIG. 20 having medium jets dispensed by nozzles for the transportation of material illustrated; FIG. 23b shows an enlarged partial fragment of FIG. 23a; FIG. 24 shows a sectional view through a suction region according to the invention; FIG. 25 shows a lateral view of a third embodiment of a suction box according to the invention; FIG. 26 shows a first sectional view of FIG. 25 seen in the direction of the width of the suction box; FIG. 27 shows a three-dimensional view of FIG. 25; FIG. 28 shows a plan view of FIG. 25; FIG. 29 shows a second sectional view of FIG. 25, seen transversely to FIG. 26; FIG. 30 shows an enlarged partial fragment of FIG. 20, having a deployed peripheral cutting tool; FIG. 31 shows the peripheral cutting tool of FIG. 30 in the retracted state; and FIG. 32 shows the peripheral cutting tool of FIG. 30 in the emergency state.

DETAILED DESCRIPTION

(8) FIG. 1 to FIG. 4 in a three-dimensional illustration show a drill head 10 according to the invention in a first embodiment. The drill head 10 has a body 11, drilling tools 12 being disposed on the lower side 13 thereof. The drill head 10 on the upper side 14 thereof has a connector 15 for a drive (not illustrated) of a drill device (not illustrated). The drive, not illustrated, here is provided directly in the drilling device, for example, the latter being disposed in a casing tube (not illustrated) or in a pile (not illustrated), for example. A further, not final, alternative can also be a top drive which is provided pile on a casing tube or on a pile and by way of which the drill head 10 is connected by way of a stem.

(9) Further variants of drives, drill devices and assemblies in a borehole/pile are likewise possible. Alternatively, the use of the drill head in conjunction with a shaft drilling machine is also possible.

(10) A In order to enable undercuts below a casing tube or a pile, for example, the body 11 on the circumference 16 thereof can have deployable peripheral cutting tools 17 which are illustrated as deployed in FIG. 1 Furthermore provided in an exemplary manner on the circumference 16 on the body 11 are consumable elements 18.

(11) The drilling tools 12 can be, for example, chisel disks 12a, peeling chisels 12b, or roller chisels 12c. The selection of the drilling tools 12 takes place as a function of the ground/rock to be loosened in order for the borehole to be established. Illustrated here are chisel disks 12a and peeling chisels 12b.

(12) A centering drilling tool 19 which enables centering of the drill head 10 is likewise provided here in the center of the lower side 13, for example.

(13) In a first embodiment, the body 11 on the lower side 13 thereof furthermore has a suction box 20. The suction box 20 is illustrated in detail in FIGS. 5 to 11. Said suction box 20 on the front side 21 thereof has an opening region 22 which has at least one opening 23.

(14) The opening 23 of the first embodiment of the suction box 20 has a classifying element 24 which subdivides the opening 23 into opening portions 23a. The grain size of the loosened ground/rock that can enter the interior space 25 of the suction box 20 is determined by the classifying element 24.

(15) The interior space 25 is formed by a lid 26 as the upper side and a base 27 as the lower side, said lid 26 and said base 27 as one embodiment here being embodied in a planar manner. Other shapes of lids and bases are likewise possible. The suction box 20 furthermore has lateral walls 28, the latter here from the front side 21 extending along the shape of the lid and of the base.

(16) As a consequence of the shape of the lid 26, of the base 27 and of the lateral walls 28, a funnel is preferably configured, for example, in that the width BB of the interior space 25 decreases as a result of the curved shape of the lateral walls 28, as a result of which the velocity of the flow of the suctioned mixture composed of the loosened ground/rock and the carrier medium increases as the width BB decreases.

(17) An opening 29 on which a connector 30 for a conveying line 31 is provided, which line during the drilling operation is connected to a pump (not illustrated) so as to perform the discharge of the loosened ground/rock, or of the mixture composed of the conveying medium and the loosened ground/rock, is provided on the rear side of the interior space 25.

(18) In the context of the first embodiment of the suction box 20 according to the invention, the height HH of the interior space 25, proceeding from the front side 21 toward the opening 29 on the rear side of the suction box 20 can additionally be varied (not illustrated), in particular enlarged so as to counteract blockages of the interior space 25 by loosened ground/rock.

(19) Furthermore, it is likewise possible for the suction box 20, here illustrated as symmetrical, to be embodied asymmetrically in that the opening 29 is disposed so as to be laterally offset, for example (not illustrated). It is particularly expedient here for the opening 29 to be disposed so as to be offset toward the circumference 16 of the body 11 so as to adapt the flow profile, for example so as to increase in a targeted manner the flow velocity in regions of the interior space 25, in those regions in which more ground/rock is loosened in the rotation in the rotating direction A and enters the interior space 25 of the suction box 20 through the opening 23.

(20) The same is also possible in that the connector 30 of the conveying line 31 opens into the interior space 25 so as to be inclined into the latter, as is illustrated in FIG. 5, for example.

(21) Friction elements 32 which enable that the suction box 20 during drilling, or rotating in the rotating direction A, respectively, can slide on the face, or at a defined spacing from the latter, respectively, are disposed on the lower side of the base 27.

(22) The opening region 22 including the opening 23, the latter extending along the front side 21, has ground loosening tools 33, here a peeling blade, for example. As a result of the ground loosening tools 33 it is possible for ground/rock in the region of the front side 21 of the suction box 20 to be loosened or picked up in a targeted manner and to be supplied to the opening 23, discharging then taking place in the latter.

(23) Additionally or alternatively, baffles (not illustrated), in order for the loosened material that is not directly suctioned in the flow direction B by the flow to be supplied to the opening region 22 and then for said material to be suctioned through the openings 23 into the interior 25, can also be provided.

(24) Above the openings 23, nozzles 34 are disposed on the front side 21 (see in an exemplary manner FIG. 9), said nozzles 34 being directed in the direction B of the opening 29 and dispensing from a carrier medium, for example a liquid or air, a jet in a direction E into the interior space 25 so that material which is situated in the interior space 25 is moved in the direction B to the opening 29. Furthermore, accumulations of loosened material can also be dissolved by the jets dispensed by the nozzles 34. When dispensing a liquid, the latter can be used, for example, or alternatively also for liquefying the loosened/conveyed material in the suction box 20 and/or the opening region 22, and thus for guaranteeing improved discharging. The conveying flow in the conveying line 31 and/or the liquefaction here are/is advantageously conceived such that the loosened/conveyed material does not back up in the opening region 22, but the opening region 22 remains substantially vacant.

(25) A cleaning element 35 is additionally provided in the opening region 22. The cleaning element 35 has rods 36 which are guided in passages 37 such that, when the rods 36 are moved in the cleaning direction C, the rods engage in the opening portions 23a of the openings 23, or in the classifying elements 24 provided therein, respectively, and remove deposited material therefrom and thus render the openings 23 passable again. The cleaning element 35 is subsequently moved out of the opening portions 23a again counter to the direction of the arrow C. Alternatively, nozzles 38 which in the cleaning direction D dispense liquid jets for cleaning, as is illustrated in an exemplary manner in FIG. 9, can also be provided for cleaning the openings or the classifying elements 24. When dispensing a liquid, the latter can be used, for example, or alternatively also for liquefying the loosened/conveyed material in the suction box 20 and/or the opening region, and thus for guaranteeing improved discharging. The conveying flow in the conveying line 31 and/or the liquefaction here are/is advantageously conceived such that the loosened/conveyed material does not back up in the opening region 22, but the opening region 22 remains substantially vacant.

(26) FIG. 12 to FIG. 15 in a three-dimensional illustration show a drill head 10 according to the invention in a second embodiment. The drill head 10 has a body 11, drilling tools 12 being disposed on the lower side 13 thereof. The drill head 10 on the upper side 14 thereof has a connector 15 for a drive (not illustrated) of a drill device (not illustrated). The drive, not illustrated, here is provided directly in the drilling device, for example, the latter being disposed in a casing tube (not illustrated) pile or in a pile (not illustrated), for example. A further, not final, alternative can also be a top drive which is provided on a casing tube or on a pile and by way of which the drill head 10 is connected by way of a stem. Further variants of drives, drill devices and assemblies in a borehole/pile are likewise possible. Alternatively, the use of the drill head in conjunction with a shaft drilling machine is also possible.

(27) In order to enable undercuts below a casing tube or a pile, for example, the body 11 on the circumference 16 thereof can have deployable peripheral cutting tools 17 which are illustrated as deployed in FIG. 1. Furthermore provided in an exemplary manner on the circumference 16 on the body 11 are consumable elements 18.

(28) The drilling tools 12 can be, for example, chisel disks 12a, peeling chisels 12b, or roller chisels 12c. The selection of the drilling tools 12 takes place as a function of the ground/rock to be loosened in order for the borehole to be established. Illustrated here are chisel disks 12c and peeling chisels 12b.

(29) A centering drilling tool 19 which enables centering of the drill head 10 is likewise provided here in the center of the lower side 13, for example.

(30) In a second embodiment, the body 11 on the lower side 13 thereof furthermore has a suction box 40. The suction box 40 is illustrated in detail in FIGS. 16 to 19. FIG. 18 shows a sectional view 102 from FIG. 16. FIG. 19 here shows an enlarged view of the encircled region from FIG. 18. The suction box 40 in the region of the front side 41 thereof has an opening region 42 which has at least one opening 43.

(31) The opening 43 of the second embodiment of the suction box 40 can have a classifying element (not illustrated here) which subdivides the opening 43 into opening portions 43a. The grain size of the loosened ground/rock that can enter the interior space 45 of the suction box 20 is determined by the classifying element.

(32) The interior space 45 is formed by a lid 46 as the upper side and a base 47 as the lower side, said lid 26 and said base 27 as one embodiment here being embodied in a planar manner. Other shapes of lids and bases are likewise possible. The suction box 40 furthermore has lateral walls 48, the latter here from the front side 41 extending along the shape of the lid and of the base.

(33) As a consequence of the shape of the lid 46, of the base 47 and of the lateral walls 48, a funnel is preferably configured, for example, in that the width BB of the interior space 45 decreases as a result of the curved shape of the lateral walls 48, as a result of which the velocity of the flow of the suctioned mixture composed of the loosened ground/rock and the carrier medium increases as the width BB decreases. Additionally, the height HH of the interior space 45 of the suction box 40, proceeding from the front side 41, varies toward the opening 49 on the rear side of the suction box 40. Said height HH in the second embodiment is enlarged so as to counteract blockages of the interior space 45 as a result of loosened ground/rock. Other variations in terms of height are likewise possible in order to generate specific flow profiles in the interior space 45. This also applies to the suction box 20 of the first embodiment.

(34) An opening 49 on which a connector 40 for a conveying line 41 is provided, which line during the drilling operation is connected to a pump (not illustrated) so as to perform the discharge of the loosened ground/rock, or of the mixture composed of the conveying medium and the loosened ground/rock, is provided on the rear side of the interior space 45.

(35) Additionally, and not illustrated here, in the context of the second embodiment of the suction box 40 according to the invention, it is possible for the suction box 40, here illustrated as symmetrical, to be embodied asymmetrically in that the opening 49 is disposed so as to be laterally offset, for example. It is particularly expedient here for the opening 49 to be disposed so as to be offset toward the circumference 16 of the body 11 so as to increase in a targeted manner the flow velocity in those regions in which more ground/rock is loosened in the rotation in the rotating direction F and enters the interior space 25 of the suction box 40 through the opening 43.

(36) Alternatively, the same is also possible in that the connector 40 of the conveying line 41 opens into the interior space 45 so as to be inclined into the latter.

(37) Disposed upstream of the opening 43 is a deflecting element 60 which by way of articulation points 61 on the suction box 40, for example on the lateral walls 48 of the latter, is disposed so as to be movable. This here is preferably a rotating movement in the rotating direction G about the articulation points 61. At least one actuator 62, for example a hydraulic cylinder, is provided for moving the deflecting element 60. Said actuator 62 is connected to, for example a first detent 63 disposed on the deflecting element 60 and to a second detent 64 disposed on the lid 46 so that the pivoting movement can be carried out when activating the actuator 62. The deflecting element 60 in this instance can be folded in the rotating direction G.

(38) At least one ground loosening tool 65 is disposed on the end of the deflecting element 60 that lies opposite the first detent 63. The deflecting element 60 can furthermore have nozzles 66 which, for example, from a carrier medium, for example a liquid or air, dispense a jet in the direction E into the interior space 45. As a result thereof, material that is situated in the interior space 45 can be moved in the direction B to the opening 49. When dispensing a liquid, the latter can be used, for example, or alternatively also for liquefying the loosened/conveyed material in the suction box 20 and/or the opening region 22, and thus for guaranteeing improved discharging. The conveying flow in the conveying line 31 and/or the liquefaction here are/is advantageously conceived such that the loosened/conveyed material does not back up in the opening region 22, but the opening region 22 remains substantially vacant.

(39) A friction element 52 disposed on a base plate 55 is provided on the base 47.

(40) As a function of the degree of pivoting of the deflecting element 60, an opening gap 67 exists between the base plate 55 and the ground loosening tool 65. The size of said opening gap 67 is determined by the quantity of material in terms of loosened ground/rock that has been picked up, for example. Classifying can furthermore be performed by way of the opening gap 67, for example, so as to prevent the entry of specific grain sizes of loosened ground/rock.

(41) Furthermore, a nozzle 68 which, as a cleaning element from a carrier medium, for example a liquid or air, dispenses a jet in the cleaning direction D so as to remove jammed material from the opening gap 67 can be disposed on the base plate 55. When dispensing a liquid, the latter can be used, for example, or alternatively also for liquefying the loosened/conveyed material in the suction box 20 and/or the opening region 22, and thus for guaranteeing improved discharging. The conveying flow in the conveying line 31 and/or the liquefaction here are/is advantageously conceived such that the loosened/conveyed material does not back up in the opening region 22, but the opening region 22 remains substantially vacant.

(42) Furthermore, an articulation element 69 that is connected to an actuator which is not illustrated and by way of which the entire suction box 40 is movable in relation to the body 11 so as to move the entire suction box 40 closer to the face, for example, or remove said suction box 40 from the latter, as a result of which the penetration depth into the face and/or the quantity of loosened material picked up are/is able to be influenced is illustrated in FIG. 19, for example.

(43) The opening 23 of the suction box 20 of the first embodiment thus faces directly the rotating direction A, whereas the opening 43 of the suction box 40 of the second embodiment is not directly reached. The loosened material that passes through the opening gap 67 first has to be deflected to the flow direction by the deflecting element 60 and fed to the opening 43. Liquefying can then take place here in a corresponding manner. The ground loosening tools 65 of the second embodiment are thus pulled across the face, while the ground loosening tools 33 of the first embodiment are pushed across the face.

(44) FIG. 20 to FIG. 23b in a three-dimensional illustration show a drill head 10 according to the invention in a third embodiment. The drill head 10 has a body 11, drilling tools 12 being disposed on the lower side 13 thereof. The drill head 10 on the upper side 14 thereof has a connector 15 for a drive (not illustrated) of a drill device (not illustrated). The drive, not illustrated, here is provided directly in the drilling device, for example, the latter being disposed in a casing tube (not illustrated) or in a pile (not illustrated), for example. A further, not final, alternative can also be a top drive which is provided on a casing tube or a pile and by way of which the drill head 10 is connected by way of a stem. Further variants of drives, drill devices and assemblies in a borehole/pile are likewise possible. Alternatively, the use of the drill head in conjunction with a shaft drilling machine is also possible.

(45) In order to enable undercuts below a casing tube or a pile, for example, the body 11 on the circumference 16 thereof can have deployable peripheral cutting tools 17 which are illustrated as deployed in FIG. 20. The individual states of the peripheral tool 17 are shown in FIGS. 29 to 31. Furthermore provided in an exemplary manner on the circumference 16 on the body 11 are consumable elements 18.

(46) The drilling tools 12 can be, for example, chisel disks 12a, peeling chisels 12b, or roller chisels 12c. The selection of the drilling tools 12 takes place as a function of the ground/rock to be loosened in order for the borehole to be established. Illustrated here are chisel disks 12a.

(47) As an alternative to the above-described centering drilling tool 19, a row of disks 12a which likewise enable centering of the drill head 10 are provided in the center of the lower side 13.

(48) In a third embodiment, the body 11 furthermore has a suction box 70. The suction box 70 is illustrated in detail in FIGS. 24 to 29. Said suction box 70 has an opening region 72 which has at least one opening 73.

(49) The opening 73 of the third embodiment of the suction box 70 has a classifying element 74 which subdivides the opening 73 into opening portions 73a. The grain size of the loosened ground/rock that can enter the interior space 75 of the suction box 70 is determined by the classifying element 74.

(50) The interior space 75 is formed by a lid 76 as the upper side and a base 73 as the lower side, as well as by lateral walls 78 and a rear wall 77.

(51) As a consequence of the shape of the lid 76, of the rear wall 77 and of the lateral walls 78, a funnel is preferably configured, for example, in that the width BB of the interior space 75 (see FIG. 26) decreases as a result of the shape and disposal of the lid 76 and of the rear wall 77, as a result of which the velocity of the flow of the suctioned mixture composed of the loosened ground/rock and the carrier medium increases as the width BB decreases.

(52) An opening 79 on which a connector 71 for a conveying line (not illustrated) is provided, which line during the drilling operation is connected to a pump (not illustrated) so as to perform the discharge of the loosened ground/rock, or of the mixture composed of the conveying medium and the loosened ground/rock, is provided on the rear side of the interior space 75.

(53) Additionally, the height HH of the interior space 75 of the suction box 70, proceeding from the opening region 72, increases toward the opening 79 on the upper side of the suction box 70 so as to counteract blockages of the interior space 75 as a result of loosened ground/rock.

(54) A nozzle bar 81 is provided in front of the opening region 72 in the rotating direction, and a second nozzle bar 80 is provided behind the opening region 72 in the rotating direction, both so as to be parallel to the opening region 72, or to the opening 73, respectively, on the lower side 13 of the drill head 10. The nozzle bars 81 have a multiplicity of nozzles 82, 83 disposed in series. These nozzles 82, 83 each dispense a jet AA, DD of a purging medium, preferably a liquid jet or a compressed air jet. The nozzles 82 of the nozzle bar 80 and the nozzles 83 of the nozzle bar 81 are disposed such that said nozzles are aligned onto the face and toward the opening region 72. The nozzles 82 here on the lower side 13 of the drill head 10 are disposed at an angle in relation to the vertical, and the nozzles 83 on the lower side 13 of the drill head 10 are disposed at an angle in relation to the vertical. The angle and the angle preferably differ from one another. The angle here is particularly preferably smaller than the angle . The jets AA here impact the face (not illustrated) and cause the loosened ground to be swirled or activated, respectively, so that this loosened ground can more readily be suctioned into the opening 73. Furthermore, a blocking effect is also created by the jets AA such that loosened ground ideally cannot exit the region CC between the jet AA and the jet DD counter to the rotating direction A. The blocking effect is improved as the angles , R between the face and the vertical increase. In contrast, the effect of loosening/accelerating the loosened ground improves up to an angle , p to be determined in an optimal manner if the angle , p decreases.

(55) The jet DD, which in comparison to the jet AA is directed straighter onto the face, substantially causes a blocking effect so that material or loosened ground, respectively, that has been activated by the jet AA and thus been accelerated in the rotating direction cannot exit the region CC in the rotating direction A.

(56) Furthermore preferably provided here on the external circumference of the lower side 13 of the drill head 10 in the region of the suction box 70 is a flow ring 84. Proceeding from the lower side 13, the flow ring 84 extends toward the face. Said flow ring here is preferably implemented as a metal sheet provided on the circumference 16 of the drill head 10. The flow ring 84 has the effect that the suctioning through the opening 73 is not performed in the form of a short circuit from the peripheral region of the borehole.

(57) In order for the suctioned liquid to be filled below the drill head 10, openings 85 here are preferably provided on the right and on the left on the short side of the opening 73 and are connected to a line (not illustrated) by way of which the liquid is fed to the intake region. It is in particular avoided as a result of the preferably targeted infeed in the intake region that crossflows are created below the drill head 10 in the extraction region, as a result of which an uncontrolled transportation of material would arise. Apart from wear, such an uncontrolled transportation of material also leads to already loosened ground being repeatedly traveled across by the drilling tools 12.

(58) In order to effect an optimal transportation of material of the loosened ground to the opening region 72 of the suction box 70, a centralizing unit is preferably provided, preferably on the lower side 13 of the drill head 10. This centralizing unit is composed of baffles and nozzles by way of which loosened ground in specific regions is fed to that region of the face that is traveled across by the opening region 72 of the suction box 70. Controlling of the material flow is effected in a simple manner as a result thereof, by way of which an optimized distribution of material from those regions in which more ground is loosened on the face to those regions in which less ground is loosened by the drilling tools 12 is able to be achieved in order to optimize the suctioning.

(59) Provided to this end are baffles 86 of various lengths and incidence angles, said baffles 86 being provided directly behind drilling tools 12 disposed in specific portions. The baffles 86 here extend from the lower side 13 of the drill head 10 toward the face. Said baffles are diagonally disposed such that the loosened material, or the loosened ground, respectively, is moved efficiently from the external regions of the lower side 13 of the drill head 10 toward the opening region 73. This transportation of material is effected by nozzles 87 which are in each case provided in a housing 88 on the external side of the lower side 13 of the drill head 10. The nozzles 87 here dispense a tangential jet EE of a purging medium (liquid or air) that impacts the respective baffle 87. The jet EE on the baffle 87 is then deflected in the flow direction HH parallel to the baffle 87. The material that is loosened by the drilling tools 12 in front of the respective baffle 86 is then transported in the direction HH by this purging medium flow.

(60) Furthermore, the peripheral cutting tools 17 also have baffles 89 which are likewise diagonally disposed such that material from the outside, as a result of the production of the drill head 10, is able to be transported along the baffle 89 toward the inner region of the lower side 13 of the drill head 10. In turn, nozzles 90 that direct a jet FF of a purging medium (liquid or air) onto the baffle 89 are also provided in a housing 91 such that the flow direction of the jet FF is changed at the baffle 89 such that said flow direction runs in the direction HH parallel to the baffle 89. A peeling chisel 12b which cuts and straightens the wall of the borehole is preferably provided on the external side of the baffle 89 of the peripheral cutting tool 17. A nozzle 92 which dispenses a jet (not illustrated) of a purging and cooling medium (liquid or air) is provided for cooling and purging the peeling chisel 12b. The jet here is directed along the peeling chisel 12b toward the face region. The loosened material that is purged here is then acquired by the baffle 89 and likewise transported away from the nozzle 90 in the flow direction HH, preferably in combination with the jet FF.

(61) In the region of the center in which the centering drilling tool 19 is embodied, the latter here preferably being embodied as a row of disks 12a, nozzles 93 are provided in a housing 94 so as to be parallel to the row, said nozzles dispensing a jet GG of a purging medium (liquid or air) in the flow direction I parallel to the row of disks 12a such that the loosened material that is loosened by the respective disks 12a is conveyed out of the center by the jets GG. Baffles 95 which here are embodied in a curved manner and disposed circumferentially on the lower side 13 of the drill head 10 in a region of the face that is traveled across by the opening region 73 of the suction box 70 are provided for delimiting this material flow.

(62) The lower side 13 of the drill head by the baffles and nozzles is divided into different material conveying portions J to M. The baffles 89 in conjunction with the nozzles 90 in the region of the peripheral cutting tools 17 have the effect of an external conveying region J, the latter being shown in FIG. 22. The ground which is loosened by the drilling tools 12 in these regions is conveyed by the baffles 89 in the flow direction HH into the regions K1 to K4 to L that are situated further inward and are concentric with the former. The regions K1 to K4 here are preferably of different sizes because the respective associated baffles 86 are preferably embodied in different length. As a result thereof, a targeted distribution of material is achieved into the annular region L or into a region K4 situated outside the latter, said region is then being travelled across by the suction box 70, as a result of which a discharge of the loosened ground takes place. These regions are likewise shown in FIG. 22. The center M is situated within the annular region L, the material loosened in said center M then being conveyed in the flow direction I against the baffles 95 and into the region L. A targeted distribution of material takes place here in such a manner that the bulk of the conveyed material can be received by the inner part of the opening region 73 such that the discharge of material, or the suctioning, respectively, is significantly improved as a result.

(63) The states of movement of the peripheral cutting tool 17 are shown in FIGS. 30 to 32. Said peripheral cutting tools 17 here have a main body 96 which is able to be moved in the direction of the arrow N. Provided to this end is an actuator 97 which here is preferably embodied as a hydraulic cylinder. FIG. 30 shows the deployed position of the peripheral cutting tools 17, while FIG. 31 shows the retracted position. The main body 96 is retracted into the body in 11 of the drill head 10 or deployed therefrom by moving a piston 98 in the cylinder 99 by way of the piston rod of said piston 98. An emergency solution for recovering the drill head 10 upon completion of the drilling works is shown in FIG. 32, in which emergency the main body is no longer able to be retracted by virtue of a malfunction or a failure of the actuator 97. Provided to this end is a shear pin 100 which in the normal operating state functions as a rotary bearing for pivoting the main body 96 into the body 11 of the drill head 10 in the moving direction N. In the event of a malfunction, this shear pin 100 is shorn off such that the main body 96 is pivotable in the direction of the arrow O about the articulation 101. The articulation 101 is the point of engagement of the actuator 97 on the main body 96.

(64) TABLE-US-00001 List of reference signs: 10 Drill head 11 Body 12 Drilling tool 12a Chisel disk 12b Peeling chisel 12c Roller chisel 13 Lower side 14 Upper side 15 Connector 16 Circumference 17 Peripheral cutting tool 18 Consumable element 19 Centering drilling tool 20 Suction box 21 Front side 22 Opening region 23 Opening 23a Opening portion 24 Classifying element 25 Interior space 26 Lid 27 Ground 28 Lateral wall 29 Opening 30 Connector 31 Conveying line 32 Friction element 34 Ground loosening tool 34 Nozzle 35 Cleaning element 36 Rod 37 Passage 40 Suction box 41 Front side 42 Opening region 43 Opening 45 Interior space 46 Lid 47 Ground 48 Lateral wall 49 Opening 50 Connector 51 Conveying line 52 Friction element 53 Ground loosening tool 54 Nozzle 55 Base plate 60 Deflecting element 61 Articulation point 62 Actuator/hydraulic cylinder 63 First detent 64 Second detent 65 Ground loosening tool 66 Nozzle 67 Opening gap 68 Nozzle 69 Articulation element 70 Suction box 71 Connector 72 Opening region 73 Opening 73a Opening portion 74 Classifying element 75 Interior space 76 Lid 77 Rear wall 78 Lateral wall 79 Opening 80 Nozzle bar primary nozzles 81 Nozzle bar secondary nozzles 82 Nozzle 83 Nozzle 84 Flow ring 85 Opening 86 Baffle 87 Nozzle 88 Housing 89 Baffle 90 Nozzle 91 Housing 92 Nozzle 93 Nozzle 94 Housing 95 Baffle 96 Main body 97 Actuator 98 Piston 99 Cylinder 100 Shear pin 101 Articulation point 102 Sectional View A Rotating direction B Flow direction C Cleaning direction D Cleaning direction