Mitre saw with angularly adjustable fence

Abstract: A miter saw includes a base, a table rotatably attached to the base, a saw assembly attached to the table, and a first fence assembly attached to the base, the first fence assembly including a work supporting surface which is movable between a first position substantially perpendicular from at least one of the table plane and the base plane, and a second position inclined relative to from the at least one of the table plane and the base plane. Another saw includes a base, a table rotatably attached to the base, a saw assembly attached to the table, and a first fence assembly attached to the base, the first fence assembly including a first workpiece supporting surface substantially perpendicular from at least one of the table plane and the base plane, and a second workpiece supporting surface which is inclined relative to from the at least one of the table plane and the base plane. Methods for obtaining compound cuts from such saws are also disclosed.

Description: This invention relates generally to miter saws and, more particularly, to a fence for a miter saw, according to the preamble of claim 1 and as known from US-A-5297463. Furthermore the invention relates to a method of making a compound cut using such a saw. Prior art miter saws typically have a base assembly 12, including a rotatable table assembly 13, a saw assembly 14, including a blade 14B, pivotally disposed on the table assembly 13 so that a user can downwardly pivot the saw assembly 13 to bring the blade 14B towards the table assembly 13, as shown in FIG. 1. The table assembly 13 is rotatable about a vertical axis to allow miter cuts. Because miter saws are commonly used for cutting crown molding, it is preferable to provide a bevel mechanism 35 to allow the saw assembly 14 to pivot about a horizontal axis for changing the angle of blade 14B relative to table assembly 13, i.e., the bevel angle. Accordingly, the crown molding M shown in FIG. 1 can be cut by rotating table assembly 13 for selecting the miter angle, rotating saw assembly 14 for selecting the bevel angle, and then downwardly pivoting the saw assembly 14 in a "chopping" action for cutting a molding M, disposed on table assembly 13. However, the bevel mechanism 35 is expensive to design and manufacture. It could increase the inaccuracy of the saw 100, creating inaccurate cuts, which result in loss of materials, time and/or money. Having a bevel mechanism 35 may require a different fence. Fences are fixedly disposed on base assembly 12 to support a workpiece during the cutting operation. In miter saws without a bevel mechanism, the fence is typically a rectangle. In miter saws having a bevel mechanism, i.e., a compound miter saw, the fence may have a large gap near the blade to provide clearance at any bevel angle. However, because of the large gap, such fence may not properly support the workpiece at the different bevel angles, causing inaccurate or rough cuts. Prior people skilled in the art have proposed using a fence assembly 20, as shown in US Patent No. 5,297,463, with a sliding fence portion 24 to provide support workpiece in all bevel angles. Such fences, however, are expensive to manufacture. US Patent No. US 5,865,079 describes a mitre saw having a support mounted on a turntable and a saw mounted on the support. A reversible fence is connected to the base to support a workpiece. The fence has opposite ends such that one end has a vertical edge portion, and the other end has an angled edge portion for supporting the workpiece during compound mitre cutting. Another prior art method for cutting crown molding is illustrated in FIG. 2, where like numerals designate like parts. Molding M is placed at an angle between fence 20 and table assembly 13. A stop 25 may be used to maintain the molding M in place. By changing the miter angle, the molding M can be cut along a compound angle without requiring bevel angle adjustments. However, because the bottom of molding M is substantially unsupported by the fence 20, it may splinter, creating an inaccurate cut, which may result in loss of materials, time and/or money. In accordance with the present invention, an improved saw is employed. The saw includes a base, a table rotatably attached to the base, a saw assembly attached to the table, and a first fence assembly attached to the base, the first fence assembly including a work supporting surface which is movable between a first position substantially perpendicular from at least one of the table plane and the base plane, and a second position inclined relative to from the at least one of the table plane and the base plane. Another saw includes a base, a table rotatably attached to the base, a saw assembly attached to the table, and a first fence assembly attached to the base, the first fence assembly including a first workpiece supporting surface substantially perpendicular from at least one of the table plane and the base plane, and a second workpiece supporting surface which is inclined relative to from the at least one of the table plane and the base plane. Additional features and benefits of the present invention are described, and will be apparent from, the accompanying drawings and the detailed description below. The accompanying drawings illustrate preferred embodiments of the invention according to the practical application of the principles thereof, and in which: FIG. 1 is a left elevational view of a first prior art compound miter saw; FIG. 2 is a left elevational view of a second prior art compound miter saw; FIG. 3 is a front perspective of a miter saw comprising a fence according to a first embodiment of the present invention; FIG. 4 is a front elevational view of the miter saw of FIG. 3; FIGS. 5A and 5B are left elevational views of the miter saw of FIG. 3, showing the fence in a substantially vertical position and an inclined position, respectively; FIG. 6 is a front perspective of a miter saw comprising a fence according to a second embodiment of the present invention; FIG. 7 is a front elevational view of the miter saw of FIG. 6; FIGS. 8A and 8B are left elevational views of the miter saw of FIG. 6, showing the fence in a substantially vertical position and an inclined position, respectively; FIG. 9 is a front perspective of a miter saw comprising a fence according to a third embodiment of the present invention; FIG. 10 is a front elevational view of the miter saw of FIG. 9; FIGS. 11A, 11B and 11C are left elevational views of the miter saw of FIG. 9, showing the fence in a substantially vertical position, a rearwardly inclined position and a forwardly inclined position, respectively; FIG. 12 is a front perspective of a miter saw comprising a fence according to a fourth embodiment of the present invention; FIG. 13 is a front elevational view of the miter saw of FIG. 12; FIGS. 14A and 14B are left elevational views of the miter saw of FIG. 12, showing the fence providing a substantially vertical surface and an inclined surface, respectively; FIG. 15 is a front perspective of a miter saw comprising a fence according to a fifth embodiment of the present invention; FIG. 16 is a front elevational view of the miter saw of FIG. 15; and FIGS. 17A and 17B are left elevational views of the miter saw of FIG. 15, showing the fence providing a substantially vertical surface and an inclined surface, respectively. The invention is now described with reference to the accompanying figures, wherein like numerals designate like parts. FIGS. 3 through 17B illustrate exemplary miter saws having a fence assembly according to the present invention, shown merely for purposes of illustration. One skilled in the art will readily recognize from the following description, taken in conjunction with the accompanying drawings and claims, that the principles of the invention are equally applicable to other miter saws or saws of types other than that shown for purposes of illustration in the drawings. Similarly, one skilled in the art will readily recognize that the principles of a fence according to the invention are also applicable to other type of powered, or even unpowered, equipment for performing an operation on a workpiece. Such equipment includes compound miter saws, dado saws, spindle shapers or sanders, or other types of powered or unpowered devices that allow placement of a workpiece in inclined positions. Referring to FIGS. 3 through 17B, miter saw 10 has a base assembly 12, including a rotatable table assembly 13, a saw assembly 14, including a blade 14B, pivotally disposed on the table assembly 13 so that a user can downwardly pivot the saw assembly 13 to bring the blade 14B towards the table assembly 13. The table assembly 13 is rotatable about a vertical axis to allow miter cuts. Saw blade 14B is at least partially enclosed by a blade guard 16 and driven by a motor 17 and a handle 18, which allows the operator to move the saw blade 14B and the blade guard 16 from a clear position free of a workpiece M to a cutting position with the saw blade 14B in cutting engagement with the workpiece. Referring to FIGS. 3 through 5B, a first embodiment of the fence according to the present invention is illustrated as fence assembly 200. Fence assembly 200 is interconnected with the base 12 and extends laterally across the table assembly 13 against which the workpiece M is fixedly positioned and supported for performing a cutting operation thereon. Preferably fence assembly 200 is disposed on both left and right sides of saw 10. Fence assembly 200 preferably comprises a workpiece supporting portion 204 that is slidably attached to post 205 via a boss 204B. Preferably post 205 has a slot 207 therein for limiting the travel range of portion 204. Boss 204B may extend through the slot 207 and treadingly engage knob 208. Portion 204 preferably comprises a downward extension 206, which extends below the top surface of base 12 through a slot 201. Extension 206 has a shaft 209 extending therethrough, which in turn extends through a slot 202 in base 12. As shown in FIG. 5A, the portion 204 can be set so that it is substantially vertical. However, the angle of portion 204 relative to base 12 and table assembly 13 can be changed by sliding boss 204B along slot 207 and shaft 209 along slot 202, as shown in FIG. 5B. (Preferably, shaft 209 is connected via connector 209C to the corresponding shaft 209 in the opposite fence assembly 200 so that both fence assemblies 200 will move in conjunction.) The user can then lock the portion 204 in the desired position by tightening knob 208. To obtain a compound angle cut, the user need only to incline the portion 204, as shown in FIG. 5B, and change the miter angle. Referring to FIGS. 6 through 8B, a second embodiment of the fence according to the present invention is illustrated as fence assembly 210. Fence assembly 210 is interconnected with the base 12 and extends laterally across the table assembly 13 against which the workpiece M is fixedly positioned and supported for performing a cutting operation thereon. Preferably fence assembly 210 is disposed on both left and right sides of saw 10. Fence assembly 210 preferably comprises a workpiece supporting portion 214 and a sliding portion 216 attached to portion 214. Sliding portion 216 is slidably received on track 217 formed in base 12, allowing for pivotal movement of the portion 214 about a substantially horizontal axis, preferably coplanar with the top surface of table assembly 13. Preferably, sliding portion 216 has a slot 213, receiving therethrough a boss (not shown) attached to the base 12. The boss is threadingly engaged to knob 218. As shown in FIG. 8A, the portion 214 can be set so that it is substantially vertical. However, the angle of portion 214 relative to base 12 and table assembly 13 can be changed by sliding portion 216 along track 217, as shown in FIG. 8B. The user can then lock the portion 214 in the desired position by tightening knob 218. To obtain a compound angle cut, the user need only to incline the portion 214, as shown in FIG. 8B, and change the miter angle. Persons skilled in the art will recognize that other means may be used to move portion 216 along track 217. For example, by disposing a rack on portion 216 and a meshing pinion on base 12, or vice versa, the user may move sliding portion 216 by rotating the pinion. Referring to FIGS. 9 through 11C, a third embodiment of the fence according to the present invention is illustrated as fence assembly 220. Fence assembly 220 is interconnected with the base 12 and extends laterally across the table assembly 13 against which the workpiece M is fixedly positioned and supported for performing a cutting operation thereon. Preferably fence assembly 220 is disposed on both left and right sides of saw 10. Fence assembly 220 preferably comprises a workpiece supporting portion 224 pivotally attached to base 12 via a hinge 226. Preferably portion 224 pivots about an axis substantially coplanar with the top surface of table 13. Portion 224 includes an extension 225. An arcuate slot 223 is disposed on base 12. A knob 228 threadingly engages a bolt 229 extending through extension 225 and slot 223. As shown in FIG. 11A, the portion 224 can be set so that it is substantially vertical. However, the angle of portion 224 relative to base 12 and table assembly 13 can be changed by rotating portion 224 forwardly or rearwardly about hinge 226, as shown in FIGS. 11B and 11C. The user can then lock the portion 224 in the desired position by tightening knob 228. To obtain a compound angle cut, the user need only to incline the portion 224, as shown in FIGS. 11B and 11C, and change the miter angle. Persons skilled in the art will recognize that other means may be used to rotate portion 224 about hinge 226. For example, by disposing a rack on base 12 and a meshing pinion on extension 225, the user may rotate portion 224 by rotating the pinion. Persons skilled in the art will also recognize that the edge nearest to blade 14B of portions 204, 214 and 224 are preferably inclined, creating a gap for clearing blade 14B when inclined. However, the resulting gap need not be as large as the gap required by a prior art fence, thus providing appropriate support to the workpiece. Referring to FIGS. 12 through 14B, a fourth embodiment of the fence according to the present invention is illustrated as fence assembly 230. Fence assembly 230 is interconnected with the base 12 and extends laterally across the table assembly 13 against which the workpiece M is fixedly positioned and supported for performing a cutting operation thereon. Preferably fence assembly 230 is disposed on both left and right sides of saw 10. Fence assembly 230 preferably comprises a workpiece supporting portion 236 attached to base 12. Workpiece supporting portion 234 may be slidably received by portion 236. Portion 234 preferably has a substantially vertical work supporting surface 234S. Portion 236 may also have a substantially vertical surface, which may be coplanar with surface 234S. Preferably portion 234 has an extension 234E which is slidably received in a channel 236C of portion 236. A screw 239 may push extensions 234E against portion 236 for locking portion 234 in place. As shown in FIG. 14A, the surface 234S is substantially vertical. However, by removing portion 234, inclined surface 236S of portion 236 is exposed, providing a supporting surface for an inclined workpiece M. In other words, the angle of the supporting surface of fence assembly 230 can be changed by installing or removing portion 234. To obtain a compound angle cut, the user need only to remove the portion 234, as shown in FIG. 14B, and change the miter angle. Referring to FIGS. 15 through 17B, a fifth embodiment of the fence according to the present invention is illustrated as fence assembly 240. Fence assembly 240 is interconnected with the base 12 and extends laterally across the table assembly 13 against which the workpiece M is fixedly positioned and supported for performing a cutting operation thereon. Preferably fence assembly 240 is disposed on both left and right sides of saw 10. Fence assembly 240 preferably comprises a workpiece supporting portion 246 attached to base 12. Portion 246 preferably has a substantially vertical work supporting surface 246S. Workpiece supporting portion 244 may be pivotally attached to portion 246 via a hinge 245. Accordingly, portion 244 is preferably pivotable about an axis which is preferably coplanar to work supporting surface 246S and/or parallel to the top surface of table assembly 13. As shown in FIG. 17A, the surface 246S is substantially vertical. However, by pivoting portion 244, inclined surface 244S of portion 244 is exposed, providing a supporting surface for an inclined workpiece M. In other words, the angle of the supporting surface of fence assembly 240 can be changed by moving portion 244. To obtain a compound angle cut, the user need only to move the portion 244, as shown in FIG. 17B, and change the miter angle. Persons skilled in the art may recognize other alternatives to the means disclosed herein. However, all these additions and/or alterations are considered to be equivalents of the present invention when they fall within the scope of the claims.

Claims: A saw (10) comprising: a base (12) having a base plane; a table (13) rotatably attached to the base, the table having a table plane; a saw assembly (14) attached to the table, the saw assembly comprising a cutting tool (14B) and a motor (17) for driving the cutting tool; a fence assembly (200, 210 220) attached to the base wherein the fence assembly (200, 210, 220) is capable of providing a workpiece supporting surface (204 -244) that is perpendicular to at least one of the table plane (13) or the base plane characterized in that the fence assembly (200, 210, 220) is also capable of providing a workpiece supporting surface that is inclined relative to at least one of the table plane or the base plane. A saw as claimed in claim 1, wherein the fence assembly (200, 210, 220) comprises a workpiece supporting surface (204 - 244) which is movable between a first position perpendicular to at least one of the table plane or the base plane, and a second position inclined relative to at least one of the table plane or the base plane. A saw as claimed in claim 1 or claim 2, wherein the fence assembly comprises a first portion (204) engaged to the base. A saw according to claim 3, wherein the first portion provides the workpiece supporting surface. A saw as claimed in claim 3, wherein the first portion is pivotally attached to the base. A saw according to claim 5, wherein the first portion is pivotally attached to the base about an axis which is coplanar with at least one of the base plane or the table plane. A saw as claimed in claim 3, 4 or 5, wherein the first portion is inclinable towards front of the table, and/or toward the rear of the table. A saw as claimed in any one of claims 3 to 7, wherein the first portion is slidably attached to the base. A saw as claimed in claim 1, wherein the fence assembly comprises a first workpiece supporting surface perpendicular to at least one of the table plane and the base plane, and a second workpiece supporting surface which is inclined relative to at least one of the table plane or the base plane. A saw as claimed in claim 3 and 9, wherein the first portion provides the first workpiece supporting surface and/or the second workpiece supporting surface. A saw as claimed in claim 3 and 9, wherein the fence assembly comprises a second portion (214) engaged to the first portion. A saw as claimed in claim 11, wherein the second portion provides the first and/or the second workpiece supporting surface. A saw as claimed in claim 11 or claim 12, wherein the second portion is slidably provided on the first portion, and/or is pivotally attached to the first portion. A saw as claimed in any one of claims 11 to 13, wherein the second portion pivots about an axis coplanar with the first workpiece supporting surface and/or substantially parallel to the table plane or base plane. A saw as claimed in any one of claims 1 to 14, wherein the fence assembly is disposed on the left hand side of the saw assembly, when viewed from a position from which the saw is operated. A saw as claimed in any one of claims 15, further comprising another fence assembly disposed on the right of the saw assembly. A saw according to claim 16, wherein the another fence assembly is interconnected with the fence assembly. A method of making a compound cut comprising the steps of: providing a miter saw (10) comprising a base (12), a table (13) rotatably attached to the base, and a saw assembly (14) attached to the table, the saw assembly comprising a cutting tool (14B) and a motor (17) for driving the cutting tool; providing a fence assembly (200 - 240) attached to the base, the fence assembly (200 - 240) comprising a work supporting surface which is movable between a first position perpendicular from at least one of the table plane or the base plane, and a second position inclined relative to from the at least one of the table plane or the base plane; moving the first fence assembly to the second position; and rotating the table. A method as claimed in claim 18, wherein the moving step comprises pivoting the first portion, and/or sliding the first portion. A method according to claim 18, wherein the fence assembly further comprises a first workpiece supporting surface perpendicular from at least one of the table plane or the base plane, and a second workpiece supporting surface which is inclined relative to from the at least one of the table plane or the base plane; exposing the second workpiece supporting surface; and rotating the table. A method as claimed in claim 20, wherein the exposing step comprises removing or pivoting the second portion.

Inventors: AYALA ADAN, EVANS SCOTT D, MEREDITH DARYL, AYALA, ADAN, EVANS, SCOTT D., MEREDITH, DARYL
Applicants: BLACK & DECKER INC, BLACK & DECKER INC.
Application year: 1999
Main classification: B27B27
IPC codes: B27B27