WO1998007544A1

WO1998007544A1 - Reciprocating saw with rocker motion

Info

Publication number: WO1998007544A1
Application number: PCT/US1997/014469
Authority: WO
Inventors: Kenneth R. Jordan; Roger Neitzell
Original assignee: Milwaukee Electric Tool Corporation
Priority date: 1996-08-19
Filing date: 1997-08-18
Publication date: 1998-02-26

Abstract

A reciprocating saw (20) having a housing (22), a spindle (24) mounted for reciprocation within the housing, and a motor for reciprocating the spindle (24). A track member (56) is interconnected with the spindle to allow the spindle to be reciprocated in a down-cutting rocking motion, a non-rocking motion, or an up-cutting rocking motion. The spindle slides within a counterweight (26) and the counterweight slidably interacts with the track member (56). A hinged bearing (90) interconnects the drive arm (48) with the spindle (24). The wobble plate (44, 46) is mounted on a wobble shaft (42) rotatable about a rotating axis, and the hinged bearing includes a cylindrical member (96) mounted to the spindle for pivoting about a pivoting axis (100) that is substantially perpendicular to the rotating axis (110). The drive arm (48) reciprocates along a reciprocating axis (112) that is substantially perpendicular to the pivoting axis, and the cylindrical member (96) is slidable relative to the drive arm along a sliding axis that is substantially perpendicular to the pivoting axis.

Description

RECIPROCATING SAW WITH ROCKER MOTION

FIELD OF THE INVENTION The present invention generally relates to the field of reciprocating saws.

BACKGROUND OF THE INVENTION Reciprocating saws are used to cut a variety of objects, such as metal pipes, wood and drywall. Such saws typically include a housing and a spindle mounted in the housing for reciprocating motion along an axis that is parallel to the longitudinal extent of the spindle. An electric motor provides power to the spindle through a mechanical reciprocating device that converts the rotary motion of a motor shaft to linear reciprocating motion. Such mechanical reciprocating devices can, for example, include an eccentric drive, as disclosed in U.S. Patent No. 5,079,844, or a wobble plate drive, as disclosed in U.S. Patent Nos. 5,025,562 and 5,050,307. In some reciprocating saws, the spindle reciprocates in an orbital reciprocating motion as opposed to a straight line reciprocating motion. The orbital motion is characterized by a forward (i.e., in the cutting direction) motion of the saw blade as the saw blade is being retracted toward the saw on the cutting stroke, and a corresponding rearward (i.e., opposite the cutting direction) motion of the saw blade as the saw blade is being extended away from the saw on the return stroke. The result is a circuitous, or orbital, path of the saw blade. Such orbital motion is believed to improve the speed at which the saw cuts a workpiece by driving the saw blade into the workpiece during the cutting stroke and withdrawing the saw blade from the workpiece during the return stroke.

Orbital motion has been achieved in a number of different ways. For example, in U.S. Patent Nos. 4,238,884 and 4,628,605, a forward force (in the cutting direction) is applied by a blade roller directly to the saw blade during the cutting stroke, and forward motion of the saw blade is accommodated by a forgiving interconnection between the spindle and the drive mechanism. In U.S. Patent No. 5,212,887, the spindle reciprocates through a pivotally-mounted bushing, and the back end of the spindle is connected to an eccentric member that provides forward-rearward motion to the spindle. In U.S. Patent Nos. 4,962,588 and 4,550,501, the back end of the spindle is moved forward-rearward by connection to a cam surface on a rotating gear, and in U.S. Patent No. 5,392,519 the back end of the spindle is moved forward-rearward by connection to an eccentric member .

SUMMARY OF THE INVENTION The utilization of blade rollers, cam surfaces, and eccentric members can be unnecessarily complicated and expensive. Further, such devices tend to wear down, and some can introduce unwanted vibrations into the saw. Accordingly, it is an object of the present invention to provide a saw that approaches the better cutting performance of orbital saws without the complexity required for orbital motion. It is a related object of the present invention to achieve a forward motion of the saw blade during the cutting stroke without resorting to orbital motion.

The above-noted objects are achieved by providing a reciprocating saw having a housing, a spindle mounted for reciprocation within the housing, a motor for moving the front end of the spindle along a first substantially linear path during the cutting stroke, and a means for selectively changing the first path of the front end to a second substantially linear path during the cutting stroke, the second path being different than (e.g., oblique to) the first path.

The means for changing the path of movement of the saw blade can include a substantially linear track member connected to the spindle and mounted for tilting (e.g., pivotally) relative to the housing. The track member is tiltable between a first position, resulting in motion of the front end of the spindle along the first path, and a second position, resulting in motion of the front end along the second path. In one embodiment, the reciprocating saw further includes a counterweight mounted for reciprocation within the housing. The spindle is slidably positioned within the counterweight, and the track member is connected to the counterweight. The track member preferably includes a longitudinal slot, and the saw further includes a follower member (e.g., a bearing) connected to the spindle and slidably positioned within the slot. The present invention further provides a method of reciprocating a spindle of a reciprocating saw, including the steps of moving the front end of the spindle along a first substantially linear path during the cutting stroke, and changing the first path of the front end to a second substantially linear path during the cutting stroke, the second path being different than the first path. Preferably, the reciprocating saw further includes a substantially linear track member connected to the spindle and mounted for tilting relative to the housing, and the changing step includes the step of tilting the track member from a first position, resulting in motion of the front end along the first path, to a second position, resulting in motion of the front end along the second path. The saw can further include a counterweight mounted for reciprocation along a first counterweight path, wherein the spindle is slidably positioned within the counterweight. In this embodiment, the changing step can include the step of moving the counterweight along a second counterweight path different than the first counterweight path.

In another aspect, the present invention provides a reciprocating saw including a housing, a spindle mounted for reciprocation within the housing, a motor for reciprocating the front end of the spindle along a first path (e.g., substantially linear path) during both the cutting and return strokes, and a means for selectively changing the first path of the front end of the spindle to a second path (e.g., substantially linear path) during both the cutting and return strokes, the second path being different than the first path. The changing means preferably includes a substantially linear track member interconnected with the spindle and mounted for tilting relative to the housing. The track member is tiltable between a first position, resulting in motion of the front end along the first path, and a second position, resulting in motion of the front end along the second path. The reciprocating saw can further include a counterweight mounted for reciprocation within the housing, wherein the spindle is slidably positioned within the counterweight, and wherein the track member is interconnected with the counterweight. Preferably, the track member includes a longitudinal slot, and the reciprocating saw further includes a follower member interconnected with the spindle and slidably positioned within the slot.

The present invention further provides a method of reciprocating a spindle of a reciprocating saw, the method including the steps of reciprocating the front end along a first path during both the cutting and return strokes, and selectively changing the first path of the front end to a second path during both the cutting and return strokes, wherein the second path is different than the first path. Preferably, the second path is substantially linear.

In yet another aspect, the present invention provides a reciprocating saw including a housing, a spindle mounted for reciprocation within the housing and having a first cutting direction and a second cutting direction opposite the first cutting direction, a means for moving the front end along a first (e.g., linear) cutting path during the cutting stroke, the first cutting path characterized by movement at least partially in the first cutting direction, and a means for selectively changing the saw such that the front end moves along a second (e.g., linear) cutting path during the cutting stroke, the second cutting path characterized by movement at least partially in the second cutting direction. Preferably, the changing means can selectively change the saw such that the front end moves along a neutral cutting path during the cutting stroke, the neutral cutting path characterized by movement substantially perpendicular to the first and second cutting directions.

The present invention further provides a method of reciprocating a spindle of a reciprocating saw, including the steps of moving the front end along a first cutting path during the cutting stroke, the first cutting path characterized by movement at least partially in a first cutting direction, and changing the saw such that the front end moves along a second cutting path during the cutting stroke, the second cutting path characterized by movement at least partially in a second cutting direction opposite the first cutting direction. The method can further include the step of changing the saw such that the front end moves along a neutral cutting path during the cutting stroke, the neutral cutting path characterized by movement substantially perpendicular to the first and second cutting directions.

The present invention also provides a reciprocating saw including a housing, a spindle mounted for reciprocation within the housing, a bearing member mounted with the housing and positioned to support the spindle for reciprocating motion and rocking motion, and a track member mounted to the housing and being connected to the spindle. The track member is designed to move the rear end of the spindle along a path that results in rocking motion of the bearing member.

The track member is preferably movable between a first position, resulting in oblique movement of the rear end of the spindle and rocking motion of the bearing member, and a second position, resulting in no oblique movement of the rear end and substantially no rocking of the bearing member. For example, the track member can be pivotally mounted to the housing. In one embodiment, the track member includes a longitudinal slot, and the reciprocating saw further includes a follower member interconnected with the spindle and movably positioned within the slot. The present invention further provides a reciprocating saw including a hinged bearing interconnecting the drive arm with the spindle. The hinged bearing preferably includes a cylindrical member pivotably mounted to the spindle and slidably interconnected with the drive arm. For example, the cylindrical member can include an opening for slidably receiving a portion of the drive arm. Preferably, the hinged bearing is arranged such that the drive arm does not directly contact the spindle.

In one embodiment, the wobble plate is mounted on a wobble shaft rotatable about a rotating axis, the cylindrical member is slidable relative to the drive arm along a sliding axis, and the drive arm reciprocates along a reciprocating axis. The cylindrical member is pivotably mounted to the spindle for pivoting about a pivoting axis that is perpendicular to one or more of the above-mentioned axes.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a partial side section view of a reciprocating saw embodying the present invention with the guide member in a down-cutting position and the spindle in a fully retracted position. Fig. 2 is the partial side section view of Fig. 1 with the spindle in a fully extended position.

Fig. 3 is a front view of the reciprocating saw shown in Fig. 1. Fig. 4 is a partial right side view of the reciprocating saw shown in Fig. 1.

Fig. 5 is a section view taken along line 5-5 in Fig. 1. Fig. 6 is a section view taken along line 6-6 in

Fig. 1.

Fig. 7 is a right side view of the reciprocating saw taken along line 7-7 in Fig. 5.

Fig. 8 is a section view taken along line 8-8 in Fig. 5.

Fig. 9 is a section view taken along line 9-9 in Fig. 5.

Fig. 10 is a perspective assembly view of the housing insert, follower member, eccentric cam member and adjustment knob.

Fig. 11 is a partial side view of the internal drive components of the reciprocating saw of Fig. 1 with the guide member in a substantially neutral or non-rocking position. Fig. 12 is a partial side view of the internal drive components of the reciprocating saw of Fig. 1 with the guide member in an up-cutting position.

Fig. 13 is a perspective assembly view of an alternative connection between the wobble plate drive arm and the spindle.

Fig. 14 is a section view of the alternative connection shown in Fig. 13. DETAILED DESCRIPTION

Figs. 1 and 2 illustrate a reciprocating saw 20 embodying the present invention. The reciprocating saw

20 generally includes a main housing 22, a spindle 24 reciprocatably mounted within the housing 22, and a counterweight 26 reciprocatably mounted with the housing

22. The spindle 24 includes a front end 28 that supports a saw blade 30, which is designed to cut in a cutting direction 32 (i.e., in the direction of the saw teeth) opposite a non-cutting direction 34. The spindle 24 reciprocates the saw blade 30 through a cutting stroke (usually toward the housing 22) and a return stroke (usually away from the housing 22). The counterweight 26 provides a vibration-reducing force that at least partially counteracts the forces created by movement of the spindle 24 and the saw blade 30.

A drive means in the form of an electric motor (not shown) is mounted in the housing 22. The motor includes a drive pinion 36 that engages a gear 38 mounted on a jack shaft 40 that is rotatably mounted within the housing 22. A wobble shaft 42 is positioned over the jack shaft 40 and is designed to drive primary and secondary wobble plates 44,46 in a conventional manner. The primary wobble plate 44 includes a primary drive arm 48 that extends through a slot 50 (Fig. 6) in the counterweight 26 to drivingly engage the reciprocating spindle 24. The secondary wobble plate 46 includes a secondary drive arm 52 that drivingly engages the counterweight 26.

In addition to being mounted for reciprocating motion, the reciprocating spindle 24 is also mounted for rocking motion relative to the housing 22. Such rocking motion is facilitated by a spherical bearing sleeve 54 pivotably mounted within the housing 22. The spherical bearing sleeve 54 rocks relative to the housing 22, and the reciprocating spindle 24 reciprocates through the bearing sleeve 54. It should be appreciated that, instead of a spherical bearing sleeve 54, the bearing sleeve 54 could comprise a plane bearing sleeve mounted to the housing 22 for pivoting motion about a horizontal axis. The illustrated reciprocating spindle 24 is designed to move in three distinct motions : a down-cutting rocking motion, a substantially neutral or non-rocking motion, and an up-cutting rocking motion. Figs. 1 and 2 illustrate the down-cutting rocking motion. Such motion is generated due to the interconnection between the spindle 24 and an inclined track member 56. Such interconnection is provided by the interconnection between a rear end 58 of the spindle 24 and the counterweight 26, and further by the interconnection between the counterweight 26 and the inclined track member 56. More specifically, the rear end 58 of the spindle 24 is designed to be supported by and to slide within the counterweight 26. Accordingly, any oblique motion (i.e., angled relative to the longitudinal extent of the reciprocating spindle 24) of the counterweight 26 will result in oblique motion of the rear end of the spindle 24 and rocking motion of the spindle 24 about the spherical bearing sleeve 54.

Referring to Fig. 5, in addition to riding on the reciprocating spindle 24, the counterweight 26 is slidably interconnected with the track member 56. In this regard, two follower members in the form of bearings 60 are secured to opposing sides of the counterweight 26 and slidably engage a slot 62 in the track member 56. Because the track member 56 is inclined relative to the longitudinal extent of the counterweight 26 (as shown in Fig. 1), the sliding interaction between. the counterweight 26 and the track member 56 will result in oblique movement of the counterweight 26 as the counterweight 26 is reciprocated within the housing 22. More specifically, as the counterweight 26 is moved from the position shown in Fig. 1 to the position shown in Fig. 2, the counterweight 26 moves downwardly (as viewed in Figs. 1 and 2) within the housing 22, resulting in upward movement of both the front end 28 of the spindle 24 and the corresponding saw blade 30. During this upward movement of the saw blade 30, the spindle 24 is being extended. As the spindle 24 is being retracted, the counterweight 26 is extended and moved upward slightly, following the track member 56. Such upward movement of the counterweight 26 results in downward movement of the saw blade 30. Accordingly, it can be seen that the saw blade 30 moves downward slightly (i.e., in the cutting direction 32) during the cutting stroke, and upward slightly (i.e., in the non-cutting direction 34) during the return stroke. However, the cutting stroke and return stroke occur along the same path, and therefore the path of the saw blade 30 is not orbital.

In the illustrated embodiment, the slot 62 in the track member 56 is substantially linear. Alternatively, the slot could be curved.

Turning to Fig.6, in order to accommodate oblique movement of the counterweight 26, the interconnection between the secondary drive arm 52 and the counterweight 26 is provided by a spherical slide bearing 64. More specifically, the spherical slide bearing 64 provides for rocking motion between the secondary drive arm 52 and the counterweight 26, and the secondary drive arm 52 is also slidable within the spherical slide bearing 64 to accommodate transverse movement of the counterweight 26 relative to the secondary drive arm 52. Similarly, the primary drive arm 48 is interconnected with the spindle 24 by a spherical slide bearing (not shown).

In order to allow the path of the saw blade 30 to be adjusted, the angle of the track member 56 is adjustable. More specifically, referring to Figs. 3-5 and 7-9, the track member 56 is pivotally mounted to a housing insert 66 by a pivot member 68. Adjustment of the angle of the track member 56 is accomplished by rotating an adjustment knob 70. The adjustment knob 70 can be rotated to provide rotation to an eccentric cam member 72 having an eccentric pin 74 that slidably engages an adjustment slot 76 in the track member 56. As the eccentric cam member 72 is rotated, the eccentric pin 74 provides transverse movement to the front end 78 of the track member 56, thereby causing rotation of the track member 56 about the pivot member 68.

Referring to Fig. 10, to secure the position of the track member 56, the adjustment knob 70 is provided with two teeth 80 designed to selectively engage three pairs of corresponding recesses 82 in the housing insert 66. The adjustment knob 70 is biased toward the housing insert 66 by a spring 84 and a corresponding spring stop 86 secured to the eccentric cam member 72. Rotation of the adjustment knob 70 is accomplished by pulling the adjustment knob 70 away from the housing insert 66 until the teeth 80 are disengaged from the recesses 82 in the housing insert 66. Subsequently, the adjustment knob 70 can be rotated until the teeth 80 are aligned with a different pair of recesses 82. The adjustment knob 70 can then be released whereby the spring 84 will force the adjustment knob 70 and corresponding teeth 80 toward the housing insert 66 and into the corresponding recesses 82. The positions of the three pairs of recesses 82 in the housing insert 66 correspond with the three desired motions of the saw blade 30: down-cutting rocking otion, substantially neutral or non-rocking motion, and up-cutting rocking motion.

Fig. 11 illustrates the reciprocating saw 20 with the track member 56 in the substantially neutral or non- rocking position, resulting in movement of the front end 28 of the reciprocating spindle 24 in a path different than described above with respect to Fig. 1. Such positioning of the track member 56 is accomplished by rotating the adjustment knob 70, as described above in more detail. With the track member 56 in this position, the counterweight 26 and spindle 24 will not significantly rock about the spherical bearing sleeve 54, thereby resulting in a neutral or non-rocking motion of the saw blade 30. The neutral motion of the saw blade 30 is generally illustrated in Fig. 11 with the fully extended position of the saw blade 30 shown in solid lines and the fully retracted position of the saw blade 30 shown in broken lines. With the track member 56 in this position, the reciprocating saw 20 can be used for either up-cutting (as illustrated) or down-cutting.

Fig. 12 illustrates the reciprocating saw 20 with the track member 56 positioned in an up-cutting rocking position, resulting in movement of the front end 28 of the reciprocating spindle 24 in a path different than described above with respect to Figs. 1 and 11. As noted above, such positioning of the track member 56 is accomplished by rotating the adjustment knob 70 to the appropriate position. With the track member 56 in this position, the saw blade 30 will follow the illustrated path, with the fully extended position of the saw blade 30 shown in solid lines and the fully retracted position of the saw blade 30 shown in broken lines. With the track member 56 in this position, the reciprocating saw 20 can be used for up-cutting in a cutting direction opposite that shown in Fig. 1.

Figs. 13 and 14 illustrate an alternative way to interconnect the wobble plate with the spindle. Instead of using a spherical slide bearing as described above in connection with Figs. 1-12, the apparatus of Figs. 13 and 14 utilizes a sliding hinged bearing 90 that allows relative sliding between the spindle 92 and the wobble plate 94. In the illustrated embodiment, the hinged bearing 90 includes a pin member in the form of a cylindrical member 96 positioned within a lateral opening 98 in the spindle 92. The lateral opening 98 is dimensioned such that the cylindrical member 96 is rotatable within the lateral opening 98 about a pivoting axis 100. The cylindrical member 96 is longer than the width of the spindle 92 so that the ends of the cylindrical member 96 protrude beyond the sides of the spindle 92 (see Fig. 14).

The cylindrical member 96 includes a vertical opening 102 dimensioned to slidably receive a drive portion 104 of the wobble plate 94 for sliding along a sliding axis 106. The wobble plate 94 is mounted on a wobble shaft 108 (not shown in Fig. 13) that rotates about a rotating axis 110, and the wobble plate 94 reciprocates along a reciprocating axis 112. In the illustrated embodiment, the pivoting axis 100 is substantially perpendicular to all of the sliding axis 106, the reciprocating axis 112, and the rotating axis 110.

The spindle 92 slides within a counterweight 114 (see Fig. 14), as described above in connection with Figs. 1-12. The counterweight 114 includes opposing grooves 116 that are dimensioned to slidably receive the exposed ends of the cylindrical member 96. This configuration maintains the cylindrical member 96 generally centered with respect to the spindle 92, and further inhibits rotation of the counterweight 114 relative to the wobble plate 94.

The configuration of Figs. 13 and 14 operates to provide a mechanical interconnection between the wobble plate 94 and the spindle 92 such that the reciprocating motion of the wobble plate 94 is transferred to the spindle 92. The sliding connection between the drive portion 104 and the cylindrical member 96 accommodates orbital or rocking motion of the spindle 92. Rotation of the spindle 92 is prevented by the interaction between the wobble plate 94, the cylindrical member 96 and the spindle 92, without direct contact between the wobble plate 94 and the spindle 92.

The foregoing description of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings, and the skill or knowledge of the relevant art, are within the scope of the present invention. The embodiments described herein are further intended to explain best modes known for practicing the invention and to enable others skilled in the art to utilize the invention in such, or other, embodiments and with various modifications required by the particular applications or uses of the present invention. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art .

Claims

What is claimed is:

1. A reciprocating saw comprising: a housing; a spindle mounted for reciprocation within said housing, said spindle having a front end adapted to support a saw blade movable through a cutting stroke and a return stroke; a motor for moving said front end of said spindle along a first substantially linear path during the cutting stroke; and a means for selectively changing the first path of said front end to a second substantially linear path during the cutting stroke, said second path being different than the first path.

2. A reciprocating saw as claimed in claim 1, wherein said changing means includes a substantially linear track member interconnected with said spindle, said track member being tiltable between a first position, resulting in motion of said front end along the first path, and a second position, resulting in motion of said front end along the second path.

3. A reciprocating saw as claimed in claim 2, further comprising a counterweight mounted for reciprocation within said housing, wherein said spindle is slidably positioned within said counterweight, and wherein said track member is interconnected with said counterweight .

4. A reciprocating saw as claimed in claim 2, wherein said track member includes a longitudinal slot, and wherein said saw further includes a follower member interconnected with said spindle and slidably positioned within said slot.

5. A reciprocating saw as claimed in claim 4, wherein said track member is pivotally connected to said housing.

6. A reciprocating saw as claimed in claim 4, wherein said follower member includes a bearing positioned with said slot.

7. A method of reciprocating a spindle of a reciprocating saw, the spindle having a front end adapted to receive a saw blade movable through a cutting stroke and a return stroke, said method comprising the steps of: moving the front end along a first substantially linear path during the cutting stroke; and changing the first path of the front end to a second substantially linear path during the cutting stroke, the second path being different than the first path.

8. A method as claimed in claim 7, wherein the reciprocating saw further includes a substantially linear track member connected to the spindle, and wherein said changing step includes the step of tilting the track member from a first position, resulting in motion of the front end along the first path, to a second position, resulting in motion of the front end along the second path.

9. A method as claimed in claim 7, wherein the saw further includes a counterweight mounted for reciprocation along a first counterweight path, wherein the spindle is slidably positioned within the counterweight, and wherein the changing step includes the step of moving the counterweight along a second counterweight path different than the first counterweight path.

10. A reciprocating saw comprising: a housing; a spindle mounted for reciprocation within said housing, said spindle having a front end adapted to receive a saw blade movable through a cutting stroke and a return stroke; a motor for reciprocating said front end along a first path during both the cutting and return strokes; and a means for selectively changing the first path of said front end to a second path during both the cutting and return strokes, said second path being different than the first path.

11. A reciprocating saw as claimed in claim 10, wherein said first and second paths are substantially linear.

12. A reciprocating saw as claimed in claim 10, wherein said changing means includes a track member interconnected with said spindle and tiltable between a first position, resulting in motion of said front end along the first path, and a second position, resulting in motion of said front end along the second path.

13. A reciprocating saw as claimed in claim 12, further comprising a counterweight mounted for reciprocation within said housing, wherein said spindle is slidably positioned within said counterweight, and wherein said track member is interconnected with said counterweight .

14. A reciprocating saw as claimed in claim 12, wherein said track member includes a longitudinal slot, and wherein said reciprocating saw further includes a follower member interconnected with said spindle and slidably positioned within said slot.

15. A method of reciprocating a spindle of a reciprocating saw, the spindle having a front end adapted to receive a saw blade movable through a cutting stroke and a return stroke, said method comprising the steps of: reciprocating said front end along a first path during both the cutting and return strokes; and selectively changing the first path of said front end to a second path during both the cutting and return strokes, the second path being different than the first path.

16. A method as claimed in claim 15, wherein the second path is substantially linear.

17. A reciprocating saw comprising: a housing; a spindle mounted for reciprocation within said housing, said spindle having a front end adapted to receive a saw blade movable through a cutting stroke and a return stroke, said spindle having a first cutting direction and a second cutting direction opposite the first cutting direction; a means for moving said front end along a first cutting path during the cutting stroke, the first cutting path characterized by movement at least partially in the first cutting direction; and a means for selectively changing said saw such that said front end moves along a second cutting path during the cutting stroke, the second cutting path characterized by movement at least partially in the second cutting direction.

18. A reciprocating saw as claimed in claim 17, wherein said first cutting path is substantially linear.

19. A reciprocating saw as claimed in claim 17, wherein said second cutting path is substantially linear.

20. A reciprocating saw as claimed in claim 17, wherein said changing means can selectively change said saw such that said front end moves along a neutral cutting path during the cutting stroke, the neutral cutting path characterized by movement substantially perpendicular to the first and second cutting directions.

21. A method of reciprocating a spindle of a reciprocating saw, the spindle having a front end adapted to receive a saw blade movable through a cutting stroke and a return stroke, the spindle having a first cutting direction and a second cutting direction opposite the first cutting direction, said method comprising the steps of: moving the front end along a first cutting path during the cutting stroke, the first cutting path characterized by movement at least partially in the first cutting direction; and changing the saw such that the front end moves along a second cutting path during the cutting stroke, the second cutting path characterized by movement at least partially in the second cutting direction.

22. A method as claimed in claim 21 further comprising the step of changing the saw such that the front end moves along a neutral cutting path during the cutting stroke, the neutral cutting path characterized by movement substantially perpendicular to the first and second cutting directions.

23. A reciprocating saw comprising: a housing; a spindle mounted for reciprocation within said housing, said spindle having a front end adapted to receive a saw blade movable through a cutting stroke and a return stroke, and a rear end opposite said front end; a bearing member mounted with said housing and positioned to support said spindle for reciprocating motion and rocking motion; and a track member interconnected with said spindle and designed to move said rear end of said spindle along a path that results in rocking motion of said bearing member.

24. A reciprocating saw as claimed in claim 23, wherein said track member is movable between a first position, resulting in oblique movement of said rear end of said spindle and rocking motion of said bearing member, and a second position, resulting in no oblique movement of said rear end and substantially no rocking of said bearing member.

25. A reciprocating saw as claimed in claim 24, wherein said track member is pivotally mounted to said housing.

26. A reciprocating saw as claimed in claim 24, wherein said track member is substantially linear.

27. A reciprocating saw as claimed in claim 23, wherein said track member includes a longitudinal slot, and wherein said reciprocating saw further comprises a follower member interconnected with said spindle and movably positioned within said slot.

28. A reciprocating saw comprising: a housing; a spindle mounted for reciprocation within said housing; a wobble plate having a drive arm for providing reciprocating motion to said spindle; and a hinged bearing interconnecting said drive arm with said spindle.

29. A reciprocating saw as claimed in claim 28, wherein said wobble plate is mounted on a wobble shaft rotatable about a rotating axis, and wherein said hinged bearing includes a cylindrical member mounted to said spindle for pivoting about a pivoting axis that is substantially perpendicular to said rotating axis.

30. A reciprocating saw as claimed in claim 28, wherein said hinged bearing includes a cylindrical member pivotably mounted to said spindle, said cylindrical member being slidably interconnected with said drive arm.

31. A reciprocating saw as claimed in claim 30, wherein said cylindrical member includes an opening for slidably receiving a portion of said drive arm.

32. A reciprocating saw as claimed in claim 28, wherein said hinged bearing includes a cylindrical member mounted to said spindle for pivoting about a pivoting axis, and wherein said cylindrical member is slidable relative to said drive arm along a sliding axis that is substantially perpendicular to said pivoting axis.

33. A reciprocating saw as claimed in claim 28, wherein said hinged bearing includes a cylindrical member mounted to said spindle for pivoting about a pivoting axis, and wherein said drive arm reciprocates along a reciprocating axis that is substantially perpendicular to said pivoting axis.

34. A reciprocating saw as claimed in claim 28, wherein said hinged bearing is arranged such that said drive arm does not directly contact said spindle.

35. A reciprocating saw as claimed in claim 28, wherein said hinged bearing includes a pin member pivotally mounted in said spindle, wherein at least one end of said pin member protrudes out from said spindle.

36. A reciprocating saw as claimed in claim 35, wherein said pin member has a length that is positioned substantially parallel to a width of said spindle, and wherein said length of said pin member is greater than said width of said spindle.

37. A reciprocating saw as claimed in claim 35, further comprising a counterweight mounted for reciprocation within said housing, said spindle being positioned to reciprocate within said counterweight.

38. A reciprocating saw as claimed in claim 37, wherein said counterweight includes at least one groove for accommodating said at least one end of said pin member.