Clamp with an anti-pivot and lock mechanism

Abstract

An F-type clamp with an anti-pivot and lock mechanism that engages a side of the first post facing the clamp head below a pivot axis of the guide arm of the clamp; or the anti-pivot axis engages a second side opposite the first side and above the pivot axis of the guide arm.

Claims

1. A clamp, comprising: a component engagement member including a clamp head operatively connected to a handle; a guide arm operatively connected to the component engagement member at a first end of the guide arm, and the guide arm has an opening at a second end distal the first end and the guide arm has a central axis from the first end to the second end; a first post extending through the opening and in sliding engagement with the guide arm, and the first post has a first side facing the component engagement member and a second side opposite the first side, wherein the guide arm has a pivot axis at the second end thereof relative to the first post and the pivot axis is perpendicular to the central axis of the guide arm; a second post at an end of the first post and disposed generally perpendicular to the first post and having a first end connected to the first post and a second end, distal the first end, and the second end is disposed opposite the clamp head; and, an anti-pivot and lock mechanism operatively connected to the guide arm and the first post adjacent to the opening of the guide arm, and the anti-pivot and lock mechanism is selectively adjustable relative to the first post, wherein the anti-pivot and lock mechanism engages the first post above or below the pivot axis and the central axis of the guide arm, and wherein increasing engagement of the anti-pivot and lock mechanism is configured to cause the component engagement member to rotate away from the second post.

2. The clamp of claim 1, further comprising a tab on the second end of the guide arm adjacent to the second side of the first post; and the anti-pivot and lock mechanism is operatively connected to the tab and the anti-pivot and lock mechanism is selectively adjustable relative to the first post to engage the second side of the first post, wherein the anti-pivot and lock mechanism has a central axis that is offset relative to the central axis of the guide arm or offset relative to the pivot axis of the guide arm.

3. The clamp of claim 2, wherein the tab is integrally formed with the guide arm adjacent the opening of the guide arm and protrudes toward the end of the first post opposite the second post or protrudes toward the second post, and the clamp further comprises an internally threaded aperture through the tab and a thumb screw with an externally threaded portion for threaded engagement with the aperture.

4. The clamp of claim 3, wherein the thumb screw and the aperture have a common central axis which is offset relative to the central axis of the guide arm toward the end of the first post opposite the second post or toward the second post.

5. The clamp of claim 1, wherein the anti-pivot and lock mechanism includes a cam adjacent the first side of the first post and the cam has a cam surface that is selectively adjustable to engage and disengage the first side of the first post, wherein the cam is offset relative to the central axis and the pivot axis of the guide arm toward the second post or toward the end of the first post opposite the second post.

6. The clamp of claim 5, wherein the first post comprises a first lateral side and a second lateral side that each connect the first side and the second side, and wherein rotation of the cam moves an eccentricity of the cam across the first side in a direction from the first lateral side to the second lateral side.

7. The clamp of claim 5, wherein the first post comprises a first lateral side and a second lateral side that each connect the first side and the second side, and wherein rotation of the cam moves an eccentricity of the cam across the first side in a direction from the first lateral side to the second lateral side.

8. The clamp of claim 1, wherein increasing engagement of the anti-pivot and lock mechanism rotates the component engagement member away from the second post.

9. A clamp, comprising: a component engagement member including a clamp head operatively connected to a handle; a guide arm operatively connected to the component engagement member at a first end of the guide arm, and the guide arm has an opening at a second end distal the first end and the guide arm has a central axis from the first end to the second end; a first post extending through the opening and in sliding engagement with the guide arm, and the first post has a first side facing the component engagement member and a second side opposite the first side, wherein the guide arm has a pivot axis at the second end thereof and the pivot axis is perpendicular to the central axis; a second post at an end of the first post and disposed generally perpendicular to the first post and having a first end connected to the first post and a second end, distal the first end, and the second end is disposed opposite the clamp head; a tab on the second end of the guide arm adjacent to the second side of the first post; an anti-pivot and lock mechanism operatively connected to the tab and the anti-pivot and lock mechanism is selectively adjustable relative to the first post to engage the second side of the first post, wherein the anti-pivot and lock mechanism has a central axis that is offset relative to the central axis of the guide arm or offset relative to the pivot axis of the guide arm, wherein increasing engagement of the anti-pivot and lock mechanism rotates the component engagement member away from the second post.

10. The clamp of claim 9, wherein the tab has an internally threaded aperture and the anti-pivot and lock mechanism includes an externally threaded portion corresponding to the internally threaded aperture.

11. The clamp of claim 10, wherein the anti-pivot and lock mechanism includes a disc member connected to the externally threaded portion.

12. The clamp of claim 10, wherein the central axis of the anti-pivot and lock mechanism extends through a center of the externally threaded portion and the central axis of the anti-pivot and lock mechanism is offset relative to the central axis or the pivot axis of the guide arm toward the first end of the first post.

13. The clamp of claim 9, wherein the component engagement member includes a gear mechanism supported between the handle and the clamp head and the first end of the guide arm is operatively connected to the gear mechanism for relative movement between the gear mechanism and the guide arm.

14. The clamp of claim 13, wherein the gear mechanism is a threaded shaft, and the handle is mounted to a first end of the threaded shaft and the clamp head is mounted to a second end of the threaded shaft distal to the handle.

15. The clamp of claim 14, wherein the clamp head is pivotally attached to the second end of the threaded shaft.

16. The clamp of claim 9, wherein the first post has a first end and a second end and the second post is disposed at the second end and the tab extends from the second end of the guide arm toward the first end of the first post.

17. A clamp, comprising: a component engagement member including a clamp head operatively connected to a handle; a guide arm operatively connected to the component engagement member at a first end of the guide arm, and the guide arm has an opening at a second end distal the first end and the guide arm has a central axis from the first end to the second end; a first post extending through the opening and in sliding engagement with the guide arm, and the first post has a first side facing the component engagement member and a second side opposite the first side, wherein the guide arm has a pivot axis at the second end thereof relative to the first post and the pivot axis is perpendicular to the central axis of the guide arm; a second post at an end of the first post and disposed generally perpendicular to the first post and having a first end connected to the first post and a second end, distal the first end, and the second end is disposed opposite the clamp head; an anti-pivot and lock mechanism operatively connected to the guide arm and the first post adjacent to the opening of the guide arm, and the anti-pivot and lock mechanism is selectively adjustable relative to the first post, wherein the anti-pivot and lock mechanism engages the first post above or below the pivot axis and the central axis of the guide arm; and, wherein the anti-pivot and lock mechanism comprises a cam operatively connected to the to the guide arm and is moveable to engage the first side of the first post above or below the central axis and the pivot axis of the guide arm and disengage from the first side of the first post while remaining connected to the guide arm, wherein increasing engagement of the anti-pivot and lock mechanism rotates the component engagement member away from the second post.

18. The clamp of claim 17, wherein the cam is a cam disc that is pivotally connected to the guide arm and to pivot a cam surface thereof to engage and disengage the first side of the first post.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and other advantages of the invention will become more apparent from the following description in view of the drawings. Similar structures illustrated in more than one figure are numbered consistently among the drawings.

(2) FIG. 1 is a side elevational view of prior art F-type clamps on a work panel or table top with a work piece.

(3) FIG. 2 is a side sectional view of a prior art F-type clamp.

(4) FIG. 2A is an expanded view of the clamp of FIG. 2, showing a gap between a first post and guide arm of the clamp.

(5) FIG. 3 is a side elevational view of the prior art F-type clamp showing a pivoting relationship of the guide arm relative to the first post.

(6) FIG. 3A is a side sectional of the F-type clamp of FIG. 3.

(7) FIG. 3B is an expanded view of FIG. 3A illustrating the pivot axis of the guide arm.

(8) FIG. 4 is a side elevational view of the prior art clamp of FIG. 1 with the work piece removed and the guide arm having slipped downward.

(9) FIG. 5 is a side elevational view of a prior art clamp with a lock mechanism with the work piece removed and the clamp head having pivoted downward.

(10) FIG. 6 is a side sectional view of an F-type clamp with the guide arm having pivoted downward.

(11) FIG. 6A is an expanded view of the F-type clamp of FIG. 6, illustrating more detail of the pivoting movement of the guide arm about this pivot axis.

(12) FIG. 7 is a perspective view of a woodworking clamp with an anti-pivot and lock mechanism in accordance with aspects of the invention.

(13) FIG. 8 is an exploded perspective view of the anti-pivot and lock mechanism for the woodworking clamp in accordance with aspects of the invention.

(14) FIG. 9 is a perspective view of the clamp in accordance with aspects of the invention positioned on a work panel.

(15) FIG. 10 is a side elevational view of the woodworking clamp, in accordance with aspects of the invention, on a work panel with a work piece and the anti-pivot and lock mechanism engaging the guide arm.

(16) FIG. 11 is an elevational view of the woodworking clamp of FIG. 10 with the work piece removed, and a second work piece positioned to be inserted between the clamp head and panel.

(17) FIG. 11A is an expanded view of the anti-pivot and locking mechanism in accordance with aspects of the invention.

(18) FIG. 12 is a bottom perspective view of a second embodiment of the invention, including a second embodiment of the anti-pivot and lock mechanism in an engaged position.

(19) FIG. 12A is an expanded view of the clamp of FIG. 12.

(20) FIG. 13 is a bottom perspective view of the second embodiment of the invention, including a second embodiment of the anti-pivot and lock mechanism in a disengaged position.

(21) FIG. 13A is an expanded view of the clamp of FIG. 13.

(22) FIG. 14 is an exploded view of the second embodiment of the invention.

(23) FIG. 15 is a side elevational view of the second embodiment of the invention in connection with a work panel or table top.

(24) FIGS. 16 and 17 are perspective views of the first embodiment with the clamp oriented so that the clamp head faces upward.

(25) FIG. 18 is a perspective view of the second embodiment with the clamp oriented so that the clamp head faces upward.

DETAILED DESCRIPTION OF THE INVENTION

(26) In describing particular features of different embodiments of the present invention, number references will be utilized in relation to the figures accompanying the specification. Similar or identical number references in different figures may be utilized to indicate similar or identical components among different embodiments of the present invention.

(27) It is to be noted that the terms first, second, and the like as used herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms a and an do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. Notwithstanding that the numerical ranges and parameters setting forth the broad scope are approximations, the numerical values set forth in specific non-limiting examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all sub-ranges subsumed therein. As a non-limiting example, a range of less than 10 can include any and all sub-ranges between (and including) the minimum value of zero and the maximum value of 10, that is, any and all sub-ranges having a minimum value of equal to or greater than zero and a maximum value of equal to or less than 10, e.g., 1 to 7. It is to be noted that all ranges disclosed within this specification are inclusive and are independently combinable.

(28) The inventor of the subject invention has developed an F-type clamp that includes an anti-pivot and lock mechanism that holds the guide arm and clamp head in stable position so the position of the guide arm and clamp head relative to a work surface does not have to be adjusted during use for example with multiple workpieces of the same thickness. The anti-pivot and lock mechanism is selectively adjustable relative to a first post of the clamp to engage the first post at a point are area that offset relative to a pivot axis of the guide arm and offset relative to a central axis of the guide arm.

(29) Aspects of the invention may include a thumb screw selectively adjustable relative to the first post and the thumb screw has a central axis that is offset relative to the pivot axis or central axis of the guide arm toward a first end or second end of a clamping post of the F-type clamp.

(30) Another aspect of the invention involves an anti-pivot and lock mechanism that includes an adjustable cam disc that is selectively adjustable selectively adjustable relative to the first post and engages the first post at a point or area that is offset relative to the pivot axis or central axis of the guide arm toward a first end or second end of a clamping post of the F-type clamp.

(31) In reference to FIGS. 7 and 8, a clamp 40 is illustrated and includes a component engagement member 41 that may further include a handle 42 affixed to one end of a threaded shaft 44 and a clamp head 46 pivotally attached to the other end of the other threaded shaft 44. In an embodiment, the clamp head 46 may include a disc 47 fabricated from a metal alloy such as stainless steel and a cap member 49 fitted over the disc member 47. The cap member 49 may be fabricated from a natural or synthetic rubber, or a plastic material. Embodiments may include the clamp head 46 pivotally interconnected to the shaft 44. By way of example, a ball and socket type joint (not shown) may be provided so the clamp head 46 pivots relative to the shaft 44.

(32) A guide arm 48 is provided in threaded engagement with the threaded shaft 44 at a first end 48A thereof and supports a first post 50 at a second end 48B. The first post 50 is connected in linear sliding engagement with the guide arm 48 to accommodate different thicknesses of items to be clamped together. More specifically, the second end 48B of the guide arm 48 has an opening 51 (FIG. 8) through which the first post 50 extends and is selectively slidable therein or there through to different positions to accommodate different size work pieces for clamping. The first post 50 has a first end 50A and a second end 50B, and has a first side 50C facing the component engagement member 41 and a second side 50D opposite to the first side 50C and facing away from the component engagement member 41.

(33) A second post 52 (also referred to herein as clamping post) is attached to the second end 50B of the first post 50 and preferably, substantially 90 and extends toward the clamp head 46. The term substantially or generally perpendicular means within 5 of 90, and preferably within 2 of 90. The first post 50 and second post 52 may be separate parts that are welded together, or other fastening mechanisms may be used to secure the posts, 50, 52 together. Alternatively, the first and second posts 50, 52 may be forged or made as a single integral component.

(34) As will be explained in more detail below, in an embodiment when clamping two components together, the second post 52 is inserted into a channel of an auxiliary (or second) component to be clamped to a wood working apparatus. The second or auxiliary component, which may be a wooden member with one or more channels, is positioned against a surface, such as a fence of a table or table saw or router table (or a first component), and the clamp head 46 is positioned on the auxiliary component by sliding the guide arm 48 along the first post 50, or sliding the engagement member 41 and guide arm 48, including the clamp head 46, toward a work piece on the first and/or second components. The handle 42 is then rotated thereby rotating the threaded shaft 44 so the clamp head 46 moves linearly toward the workpiece securing the workpiece to the first and/or second components.

(35) The clamp 40 and auxiliary or second component (also referred to as a work panel) may be of the type described in U.S. Pub. No. 2015/0343607, which is incorporated herein by reference in its entirety. More specifically, the second post 52 and channel of the work panel may have cross-section trapezoid shapes, also referred to as a dovetail shape.

(36) While aspects of the invention are shown in connection with an auxiliary work component, panel or surface as shown in FIGS. 9-11, the invention may also be used to secure work pieces or other components directly to a work table, such as a table of hole punch or other work surface.

(37) The threaded shaft 44 acts as a gear mechanism operatively connected to the guide arm 48 to facilitate relative movement of the clamp head 46, guide arm 48 and clamping post 42 to clamp two components together. While embodiments described herein include the guide arm 18 attached in threaded engagement with the threaded shaft 44 for adjustment of the second post 52 relative to the clamp head 46, the invention is not so limited, and may include other gear mechanisms or other clamping mechanisms. For example, the guide arm 48 may be operatively connected to a handle that has a lock and ratcheting mechanism to position the second post 52 relative to the clamp head 46 such as incorporated in the Quick Clamp sold by Festool. In addition, the term handle is intended to cover any type of gripping member that allows manipulation of the clamp 40, such as a knob. To that end, the invention is not limited to a rotatable handle connected to a threaded shaft.

(38) As described above, in some instances when performing wood working tasks it may be beneficial for the guide arm 48 to be locked in position relative to the first post 50, or vice versa. This may be the case when one is working with multiple work pieces that have the same thickness dimension. In an embodiment shown in FIGS. 7-11, an anti-pivot and lock mechanism 60 may be operatively connected to the guide arm 48 and first post 50 to lock these components in position relative to one another, and lock the clamp head 46 in a position. The mechanism 60 also prevents the guide arm 48 from pivoting relative to the first post 50, as described above with respect to the prior art F-type clamps.

(39) As illustrated, a tab 62 is connected to the second end 48B of the guide arm 48 adjacent to the second side 50D of the first post 50, or along the second side 50D of the first post 50. In this embodiment, the tab 62 extends toward a first end 50A of the first post 50 that is opposite to the second end 50B at which the second post 52 is disposed. The anti-pivot and locking mechanism 60 may include a screw type fastener, such as a thumb screw that includes a disc 64 and an externally threaded portion 66 that is at least partially disposed within an internally threaded aperture 68 in the tab 62.

(40) The disc 64 may be grasped and rotated so the locking mechanism 60 is selectively adjustable within the aperture 68 relative to the second side 50D of the first post 50. In this manner, the guide arm 48 can be locked in a desired position. For example, as shown in FIG. 10, two workpieces 70, 72 having the same thickness dimension T are positioned on a work panel or table top 74 for cutting. An auxiliary work panel 74 (FIGS. 9 and 10) is clamped to the table to support the workpieces 70, 72 for cutting. The panel 74 includes a plurality of channels 78 configured to receive the second post 52 of the clamp 40. The workpiece 70 is inserted between a top surface of the work panel 74 and the clamp head 46, and the handle 42 is rotated to fix the head clamp 46 against the work piece 70. The locking mechanism 60 is actuated to secure the guide arm 48 in a desired position.

(41) As shown in FIG. 11, after a cut is made in the first workpiece 70, the first workpiece 70 is removed; however, the guide arm 48 remains in position relative to the first post 50 and second post 52 so the claim head 46 is positioned to receive the second workpiece 72. No further adjustment is required of the guide arm 48, and clamp head 46 to receive the second workpiece 72 on the table or work panel 74, because the locking mechanism 50 locks the guide arm 48 in position and prevents or restricts pivoting of the guide arm 48 and clamp head 46. The guide arm of prior art clamps having a similar F-type configuration often slip, or pivot, between cutting different workpieces and the guide arm must be readjusted between cuttings. With the novel invention disclosed herein, if any readjustment is necessary, it may be to slightly tighten the clamp head 46 against the workpiece 72.

(42) Again in reference to FIG. 10, the guide arm 48 has a central axis 53 from its first end 48A to its second end 48B. As shown, the locking mechanism 60 has a central axis 61 that is offset relative to the central axis 53 of the guide arm 48. The central axis 53 of the guide arm 48 is a longitudinal axis passing through the center of the guide arm 48 from the first end 48A to the second end 48B thereof. In addition, or alternatively, the central axis 61 of the locking mechanism 60 may be offset relative to a pivot axis 63 of the guide arm 48, which pivot axis 63 is perpendicular to the central axes 53, 61. In this embodiment, the central axis 61 is offset toward the first end 50A of the first post 50. In another embodiment, the central axis 61 may be offset toward the second end 50B of the first post 50. In such an embodiment, the tab 62, for example, may extend toward the second end 50B of first post 50.

(43) Described in another manner, the central axis of the 61 of the mechanism 60 may be above or below sides or surfaces 48C or 48D, depending on the position of the mechanism 60 or the orientation of the clamp 40

(44) In either embodiment, a gap 92 (FIG. 11A) is formed between a surface of the tab 62 or a surface of the second end 48B of the guide arm 48 facing the second side 50D of the first post 50, and the threaded portion 66 of the lock mechanism 60 spans the gap 92 between the tab 62 and first post 50. Absent the anti-pivot and lock mechanism 60, this gap 92 enables the pivoting action of the guide arm 48 and clamp head 46 as described above with respect to the prior art F-type clamps.

(45) In reference to FIG. 11, the first work piece 70 has been removed and the second work piece 72 is shown positioned for insertion between the clamp head 46 and the work panel 74. As shown, the guide arm 48 and clamp head 46 remain in position such that the clamp head 46 does not pivot downward so the second work piece 72 can be readily inserted between the clamp head 46 and the work panel 70.

(46) The interface between the anti-pivot/lock mechanism 60 and the first post 50 and guide arm 48 is shown in more detail with repect to FIG. 11A. As shown, the threaded member 66 spans the gap 82 to contact the second side 50D of the post 50. As the anti-pivot/lock device 60 is screwed against the second side 50D of post 50, the tab 62 is pulled away from the post 50 slightly pivoting the guide arm 48 until guide arm 48 or second end 48B of the guide arm 48 engages the first and second sides 50C, 50D of the post at contact areas or edges 85A, 85B thereby locking the guide arm 48 against the post 50. In addition, this particular arrangement prevents or inhibits the downward pivoting of the guide arm 48 and clamp head 46 as described above with respect to the prior art F-type clamps.

(47) With respect to the embodiment shown in FIGS. 7-12A, the clamp 40 is positioned relative to workpieces 70, 72 and work panel or table top 74 with the clamp head 46 facing downward and the handle 42 extending upward; however, the invention for the clamp 40 is not so limited. As shown in FIGS. 16 and 17, the clamp 40 is operational when the clamp head 46 is facing upward and the handle 42 is extending downward.

(48) In addition, while the tab 62 is shown disposed or protruding toward the first end 50A of the first post 50, embodiments may include the tab 62 disposed or protruding toward the second end 50B of the first post 50 or toward the clamping post 52. In this manner, the central axis of the anti-pivot and locking mechanism is offset relative to the central axis 53 of the guide arm 48 and pivot axis 63 of the guide arm 48 toward the second end 50B of the first post 50 or toward the clamping post 52.

(49) FIGS. 12-14 illustrate a second embodiment of the invention in which the clamp 100 includes an anti-pivot and lock mechanism 120. The clamp 100 has a similar configuration to that of the above described clamp 10, including handle 102, threaded shaft 104 and clamp head 106. In addition, the clamp 100 includes guide arm 108 in threaded engagement with the threaded shaft 104 at a first end 108A and in linear sliding engagement with first post 110 at its second end 108B. The clamp 100 further includes the clamping post 112 at an end of the first post 110. The first post 110 has a first side 110C facing the clamp head 106 and a second side 110D opposite the first side 110C.

(50) The anti-pivot and lock mechanism 120 shown for example in FIGS. 12 and 12A is operatively connected to the guide arm 108 and depending on its position, operatively connected to the first post 110. More specifically, the anti-pivot and lock mechanism 120 engages the first side 110C of the first post 110 below the guide arm 108, or below a pivot axis or below a longitudinal, central axis of the guide arm 108. In as much as the first post 110 is slidable within or through the second end 108B of the guide arm 108, a gap 128 exists between the first post 110 and the second end 108B of the guide arm 108. As described above, the guide arm 108 has a tendency to pivot down when replacing work pieces.

(51) To that end, the anti-pivot and lock mechanism spans the gap 128 (FIG. 13A) to prevent pivoting of guide arm 108. The anti-pivot and lock mechanism includes a cam disc 122 pivotally attached to an underside 108C of the guide arm 108 and a bolt 124 is in threaded engagement with an internally threaded aperture 126 (FIG. 14) of guide arm 108. With respect to FIG. 12A, the anti-pivot and lock mechanism 120 is shown in an engaged position wherein the cam disc 122 spans the gap 128 between the guide arm 108 and the first post 110, whereby a side surface 122A abuts or engages the first side 110C of first post 110 thereby preventing downward pivot of the guide arm 108 relative to the first post 110. Note, that the guide arm 108 should engage the first post 110 as described above with respect to FIGS. 10, 11, and 11A. More specifically, a gap 128 exists between the end 108B of the guide arm 108, and the cam 122 or side surface 122A engages the first post 110 above or below the central axis 53 of the guide arm 108 or above or below the pivot axis 63 of the guide arm as shown in FIG. 15 and depending on the orientation of the clamp 100.

(52) With respect to FIGS. 13 and 13A, the anti-pivot and lock mechanism 120 is shown in a disengaged position, whereby the position of the first post 110 and clamp post 112 can be selectively and linearly adjusted relative to the guide arm 108 and clamp head 106. Once the first post 110 and clamp post 112 are appropriately positioned relative to the clamp head 106 to receive a work piece, the cam disc 122 is rotated or pivoted to engage the first side 110C of the first post 110 to lock the guide arm 108 in position and prevent downward pivot thereof.

(53) With respect to the embodiment shown in FIGS. 12-15, the clamp 100 is positioned relative to workpieces 70, 72 and work panel or table top 74 with the clamp head 106 facing downward and the handle 102 extending upward; however, the invention for the clamp 100 is not so limited. As shown in FIG. 18 the clamp 100 is operational when the clamp head 106 is facing upward and the handle 102 is extending downward.

(54) In addition, while the cam 122 is shown disposed under the guide arm 108 adjacent side 108C and toward second end 110B the first post 110, embodiments may include the cam 122 disposed on the other side 108D of the guide arm 10 disposed toward the first end 110B of the first post 110. In this manner, cam 122 is offset relative to the central axis 53 of the guide arm 48 and pivot axis 63 of the guide arm 48 toward the first end 110A of the first post 110.

(55) While the preferred embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those of skill in the art without departing from the invention herein. Non-limiting examples include a component that is described above as being attached to one part of the apparatus may alternatively be attached to a different part of the apparatus in other embodiments. Parts described as being indirectly connected may be connected directly to each other, and vice versa. Component parts may be assembled from individual pieces or may be integrally formed as a single unit. Alternative types of connectors and alternative materials may be used. The apparatus may be used with other types of power tools. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.