CN217121957U

CN217121957U - Reciprocating saw

Info

Publication number: CN217121957U
Application number: CN201890001717.XU
Authority: CN
Inventors: 林展鸿; 崔智勤
Original assignee: Techtronic Cordless GP
Current assignee: Techtronic Cordless GP
Priority date: 2018-11-02
Filing date: 2018-11-02
Publication date: 2022-08-05
Anticipated expiration: 2028-11-02
Also published as: WO2020087502A1

Abstract

A reciprocating saw is disclosed, comprising: a motor (30); a first output member (23a) and a second output member (23b) adapted to be connected to the saw blades (22a, 22 b); a first gear (38a) coupled with the first output member (23a) and a second gear (38b) coupled with the second output member (23 b). The first output member (23a) and the second output member (23b) are adapted to move independently of each other, and the first gear (38a) and the second gear (38b) are adapted to rotate when driven by the motor (30). The first gear (38a) and the second gear (38b) are formed with or connected to a first deviating member (44a) and a second deviating member (44b), respectively. The first output member (23a) and the second output member (23b) are movably coupled to the first deviating member (44a) and the second deviating member (44b), respectively, such that the first output member (23a) and the second output member (23b) are adapted to perform a reciprocating movement. There are many improvements to the reciprocating saw such as a simple and effective dual saw tooth drive mechanism and an easy to use saw tooth clamping module.

Description

Reciprocating saw

Technical Field

The present invention relates to power tools, and more particularly, to power saws having reciprocating saw blade(s).

Background

Reciprocating saws utilize motor power to drive their saw blade(s) in a reciprocating motion to cut a workpiece, such as wood. Reciprocating saws typically include two saw blades that reciprocate in a non-synchronized manner to achieve better cutting results.

However, existing dual blade reciprocating saws typically include complex drive mechanisms to achieve simultaneous driving of the two blades and at the same time the blades move in anti-phase with each other. On the other hand, conventional double blade reciprocating saws do not facilitate the attachment and detachment of the saw blade to and from the saw body.

SUMMERY OF THE UTILITY MODEL

In view of the above background, it is an object of the present invention to provide an alternative reciprocating saw which eliminates or at least alleviates the above technical problems.

The above object is achieved by combining the features of the main claims; the dependent claims disclose further advantageous embodiments of the invention.

Other objects of the present invention will appear to those skilled in the art from the following description. Accordingly, the foregoing objects are not exclusive and serve only to illustrate some of the many objects of the invention.

Accordingly, in one aspect, the present invention is a reciprocating saw comprising: a motor; a first output member and a second output member adapted to be connected to a saw blade; a first gear coupled with the first output member; and a second gear coupled with the second output member. The first output member and the second output member are adapted to move independently of each other, and the first gear and the second gear are adapted to rotate when driven by the motor. The first and second gears are formed with or connected to first and second biasing members, respectively. The first and second output members are movably coupled to the first and second biasing members, respectively, such that the first and second output members are adapted to perform reciprocating movements.

Preferably, the first gear and the second gear have the same axis of rotation. The first and second biasing members are offset from the axis of rotation.

More preferably, the first gear and the second gear are bevel gears and are adapted to be driven by bevel pinions simultaneously.

Most preferably, the first output member and the second output member each comprise a groove. The first and second biasing members are received in grooves of the first and second output members, respectively, and are adapted to move in a direction perpendicular to a reciprocating direction of the first and second output members.

According to a variant of the preferred embodiment, the first deviation member and the second deviation member are located at different angular positions with respect to the rotation axis.

According to another variant of the preferred embodiment, the first and second deviation members are stubs formed on the circular faces of the first and second gears, respectively.

According to a second aspect of the present invention, there is provided a reciprocating saw comprising: a motor; an output member driven by the motor, the output member adapted to be connected to a saw blade; and a blade clamping module disposed on the output member. The blade clamping module includes a user actuated lever connected to a locking pin. The locking pin is adapted to fit with a locking hole of the saw blade and lock the saw blade. The user actuation lever is adapted to move between a locked position, in which the locking pin locks the saw blade, and an unlocked position, in which the locking pin is spaced away from the saw blade.

Preferably, the blade clamping module further comprises a clamp body connected to the user actuated lever. The clamp body is formed with a saw blade receiving slot defined by two inner walls. The clamp body is further formed with a hole in communication with the blade receiving slot from at least one of the inner walls. The locking pin is adapted to move along the bore into or out of the slot as the user actuated lever moves between the locked and unlocked positions.

More preferably, the saw blade receiving slot is substantially "L" shaped.

According to a variant of the preferred embodiment, the blade clamping module further comprises a resilient member connected to the user actuation lever. The user actuation lever is biased into its locked position by the resilient member.

According to another variant of the preferred embodiment, the elastic member is a torsion spring comprising two legs. One of the legs is connected to the clamp body. The other leg is connected to the user actuation lever and the locking pin.

According to a third aspect of the present invention, there is provided a reciprocating saw comprising: a motor; an output member driven by the motor, the output member adapted to be connected to a saw blade; and a blade clamping module disposed on the output member. The blade clamping module comprises a locking button and a locking member. The locking button is adapted to move between a locked position, in which the locking button places the locking member in a position to lock the saw blade, and an unlocked position, in which the locking member is freely movable in a direction substantially perpendicular to the locking button.

Preferably, the locking button is formed with a ramp adapted to move the locking member to its locking position when the locking button is moved from its unlocked position to its locked position.

More preferably, the locking member is a ball.

According to a variation of the preferred embodiment, the saw blade receiving slot is substantially "L" shaped.

According to another variant of the preferred embodiment, the blade clamping module further comprises a resilient member connected to the locking button; the locking button is biased to its locking position by the resilient member.

The utility model has many advantages. First, some embodiments of the present invention are dual blade reciprocating saws that use two bevel gears to drive two output members simultaneously. The output member is driven to reciprocate in a non-synchronous manner, and this is achieved by two offset members on the two bevel gears in anti-phase. The reciprocating saw therefore includes a simple yet reliable structure for driving the saw blade.

Some other embodiments of the present invention are dual blade reciprocating saws having blade clamping modules that can each be operated by a user with one hand to mount or dismount a blade from a saw body. The user need only align the end of the blade with the L-shaped slot on the clamp body and when the user releases the user actuation lever, the blade will be automatically and securely locked. Such a design enables a conventional yet simple blade clamping mechanism to easily mount and dismount the blade from the reciprocating saw.

Drawings

The above and further features of the invention will be apparent from the following description of preferred embodiments, given by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 shows a perspective view of a dual blade reciprocating saw according to an embodiment of the present invention.

FIG. 2 shows the reciprocating saw of FIG. 1 with the housing halves removed to expose the motor and other components.

FIG. 3 illustrates a perspective view of the drive module of the reciprocating saw of FIG. 1.

Fig. 4 is a partial view of the transmission module of fig. 3 with one bevel gear and one output member removed.

Fig. 5 is a top view of the transmission module of fig. 3.

Fig. 6a to 6h show the position of the first output member and the second output member in a one-to-one manner when the bevel gear is in four different angular positions.

Figure 7 shows a perspective view of a saw blade and its corresponding blade clamping module.

Fig. 8 is an exploded view of one of the blade clamping modules of fig. 7.

Fig. 9 shows the clamp body of the saw blade clamping module of fig. 8 in isolation.

Fig. 10a to 10d show in a one-to-one manner the position of the user actuated lever and the corresponding condition of the locking pin in the blade clamping module of fig. 7.

Fig. 11a to 11f show in a one-to-one manner the steps of mounting the saw blade to the blade clamping module and the corresponding condition of the locking pin in the blade clamping module of fig. 7.

FIG. 12 shows a perspective view of two saw blades of the reciprocating saw of FIG. 1.

Figure 13 is a cross-sectional view of the saw blade of figure 12 containing a groove.

Fig. 14 shows a perspective view of the two saw blades of fig. 12 separated from each other.

Fig. 15 shows a portion of a drive module of a reciprocating saw according to another embodiment of the present invention.

Fig. 16a is a perspective view of a blade clamping module according to another embodiment of the present invention, wherein the blade clamping module is in a locked state.

Fig. 16b shows a cross-sectional view of the saw blade clamping module of fig. 16 a.

Fig. 16c is a perspective view of the saw blade clamping module of fig. 16a in an unlocked state.

Fig. 16d shows a cross-sectional view of the saw blade clamping module of fig. 16 c.

In the drawings, like numerals designate like parts throughout the several embodiments described herein.

Detailed Description

In the following claims and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

As used herein, terms such as "horizontal," "vertical," "upward," "downward," "above," "below," and similar terms are for the purpose of describing the normal direction of use of the invention, and are not intended to limit the invention to any particular orientation.

Referring now to fig. 1-2, a first embodiment of the present invention is a reciprocating saw that includes two saw blades 22. The saw blades 22 are each mounted to a front end of the housing 28 via a respective saw blade clamping module 24. The guard 20 is also mounted to the front end of the housing 28 and extends beyond the blade clamping module 24 to protect a user from the running saw blade 22 during operation. A removably mounted battery pack 24 is positioned at the rear end of the handle portion 26. The forward end of the handle portion 26 is connected to the rearward end of the housing 28. The front-to-back direction is defined herein as being substantially parallel to the direction of movement of the saw blade 22. A switch 32 is also disposed on the handle portion 26. It should be noted that, as shown in FIG. 1, the blade 22 and handle portion 26 are substantially perpendicular to the housing 28 in terms of the longitudinal direction, while the battery pack is substantially parallel to the housing 28.

Since fig. 2 removes one half of the housing 28, fig. 2 shows the motor 30 housed in the housing 28. The output of the motor 30 is connected to the transmission module 21. The transmission module is a mechanical module that converts the rotational output of the motor 30 into linear reciprocating movement of the saw blade 22 at a desired frequency and travel distance. The structure of the transmission module 21 will be described in more detail below. It should be noted that in this example, the direction of the axis of the motor shaft (not shown) of the motor 30 is substantially perpendicular to the longitudinal direction of the saw blade 22.

Turning now to fig. 3 to 5. The transmission module 21 is supported on the housing (not shown in fig. 3 to 4) of the reciprocating saw directly on the gear box (not shown) of the transmission module 21 by means of two ball bearings 36. The transmission module 21 comprises a bevel pinion 40 and two oppositely arranged

bevel gears

38a, 38 b. The transmission module 21 receives motor drive power at a bevel pinion 40 connected to a motor shaft (not shown). It should be noted that the transmission module 21 as shown in fig. 3 to 4 has an opposite orientation compared to the transmission module shown in fig. 1 and 2. The bevel pinion 40 is positioned between the two

bevel gears

38a, 38b and has its axis of rotation substantially perpendicular to the axis of rotation of the

bevel gears

38a, 38b, as best shown in FIG. 5. On the other hand, the two

bevel gears

38a, 38b have the same axis of rotation. As shown in fig. 3, the output mechanical power of the transmission module 21 is carried by two

output members

23a, 23b, which correspond one-to-one with

bevel gears

38a, 38b, respectively. The longitudinal direction of the

output members

23a, 23b and the direction of movement thereof are substantially perpendicular to the axis of rotation of the bevel pinion 40 and both

bevel gears

38a, 38 b. The

output members

23a, 23b are adapted to move independently of each other, but are both supported in a movable manner by two bushings 34 located on either side of the

bevel gears

38a, 38b, such that the two

output members

23a, 23b are limited to moving only in a linear direction generally transverse to a line connecting the centers of the

bevel gears

38a, 38 b. The

output members

23a, 23b are adapted to be removably connected to the saw blade 22 (in particular comprising two saw

blades

22a, 22b), respectively, by means of a saw blade clamping module 24, as will be described in more detail later.

For clarity, FIG. 4 shows only one of the two sets of output members and corresponding bevel gears. The output member shown in fig. 4 is the output member 23b, i.e., the left output member of the two output members when viewed rearward in the longitudinal direction thereof from the front of the reciprocating saw. A part of the output member 23b is formed into an oval shape to define the groove 47b, and the oval portion 46b is connected to the remaining part of the output member 23b exhibiting an elongated shape. The recess 47b receives a stud 44b which is fixedly connected to the circular face of the bevel gear 38 b. The stub 44b is offset from the rotational axis of the bevel gear 38b and serves as an offset member for cooperating with the recess 47b to convert the rotational movement of the bevel gear 38b into a reciprocating movement of the output member 23b, as will be described in more detail later.

Fig. 5 shows one set of output members 23b, bevel gears 38b, and one set of output members 23a, two sets of bevel gears 38 a. Although fig. 4 only shows the output member 23b and the bevel gear 38b, it should be noted that the output member 23a and the bevel gear 38a have the same structure and working principle as the output member 23b and the bevel gear 38b, and that the two sets of transmission mechanisms are mirror images of each other. Fig. 5 further shows that at the front end of the

output members

23a, 23b, respectively, two

blade clamping modules

24a and 24b are connected, which will now be discussed in more detail.

Turning now to fig. 7, the blade clamping module 24 comprises two

blade clamping modules

24a and 24b, each removably connected to the

saw blades

22a and 22b, respectively. The two

blade clamping modules

24a and 24b can be operated by the user independently of each other, and this means that neither, one, or both of the

saw blades

22a and 22b can be mounted to the reciprocating saw at any time. Fig. 7 shows the positions of the

blade clamping modules

24a, 24b offset from each other in the longitudinal direction of the

saw blades

22a and 22 b. This is because when the

blade clamping modules

24a, 24b are connected to the

output members

23a, 23b which can be moved relative to each other, the

blade clamping modules

24a, 24b also move relative to each other.

Fig. 8-9 show the components of the blade clamping module 24 a. Similar to the case of the drive mechanism, although fig. 8 only shows the blade clamping module 24a, the other blade clamping module 24B has the same structure and working principle, and therefore, for the sake of brevity, will not be described again. In the blade clamping module 24a, the clamp body 54 is fixed to the output member 23a by well-known means such as welding or screws. There is a torsion spring 52 having two short legs 52e fixed to two bosses 54c formed on the clamp body 54, respectively, and the other U-shaped leg fixed to the movable locking pin 48. In particular, the U-shaped leg comprises two parallel legs 52c and a turnaround section 52d at the end of the parallel legs 52 c. The two parallel legs 52c engage the locking pin 48 and are restrained by the two

wings

48e and 48d so that the U-shaped legs remain connected to the locking pin 48. Since the legs of the torsion spring 52 are mounted on the clamp body 54 and the locking pin 48, respectively, the locking pin 48 is adapted to move relative to the clamp body 54 and within a bore 54d formed in the clamp body 54, but is normally biased to a locked position as shown in fig. 10 a. On the other hand, the turning section 52d of the U-shaped leg engages with the mounting 50c of the user actuation lever 50, which is pivotally connected to the clamp body 54 via the boss 54 c. In this way, when the user actuation lever 50 is pivoted, the locking pin 48 also moves linearly due to the rigid connection of the U-shaped legs between the locking pin 48 and the user actuation lever 50. Fig. 9 also illustrates an L-shaped slot 54e formed in the clamp body 54 for use as a saw blade receiving slot for insertion of an L-shaped tab on a saw blade therein. The L-shaped slot 54e is defined by two inner walls 54f on the clamp body 54. The L-shaped slot 54e communicates with the bore 54d at an inner wall 54 f. The L-shaped slot 54e and the aperture 54d are aligned substantially perpendicular to each other.

Turning now to fig. 12-14, the manner of overlapping of the two saw

blades

22a, 22b is particularly illustrated. The saw blade 22b (i.e., the saw blade connected to the blade clamping module 24b and in turn connected to the output member 23b and the bevel gear 38b) has a different structure than the saw blade 22a (i.e., the saw blade connected to the blade clamping module 24a and in turn connected to the output member 23a and the bevel gear 38 a). In particular, no depressions are formed in the saw blade 22b, but the saw blade includes a circular protrusion 60d and a rectangular protrusion 60 c. Accordingly, the saw blade 22a includes an elongated recess 62 that receives the circular protrusion 60d and the rectangular protrusion 60c of the saw blade 22b when the

saw blades

22a, 22b are mounted on the reciprocating saw. The

saw blades

22a, 22b are further adapted to move relative to each other in that the circular projection 60d and the rectangular projection 60c are allowed to move within the groove 62. The edge 62c of the groove 62 is chamfered. At one end of the groove 62 there is an elongated hole 62d through which the circular protrusion 60d can pass so that the

saw blades

22a, 22b can be separated from each other, but the circular protrusion 60d cannot escape from the groove 62. This is because the circular protrusion 60d has an umbrella shape so as to be caught by the groove 62 having the chamfered edge 62 c. The rectangular protrusion 60c serves as a guide for the movement of the saw blade 22b relative to the saw blade 22 a.

Turning now to the operation of the reciprocating saw described above, fig. 6a to 6h show how the two

bevel gears

38a, 38b rotate during one cycle of blade movement. Each pair of drawings, i.e. fig. 6a and 6b, 6c and 6d, 6e and 6f, and 6g and 6h, shows different angular positions of the two

bevel gears

38a, 38b separated from each other by 90 degrees. Referring to fig. 1-4, when the user actuates the switch 32 of the reciprocating saw, the motor 30 begins to rotate, and this causes the bevel pinion 40 to rotate in a single direction. As the two

bevel gears

38a, 38b are simultaneously engaged with the bevel pinion 40, rotation of the bevel pinion causes the two

bevel gears

38a, 38b to rotate simultaneously, but in different directions. For example, if the bevel pinion 40 of fig. 3 is moved in a clockwise direction (when viewed from the top of the drive module 21 of fig. 3), the bevel gear 38b is also rotated in a clockwise direction, but the bevel gear 38a is rotated in a counterclockwise direction.

As mentioned above and shown in fig. 6a to 6h, two

stubs

44b and 44a are connected to the two

bevel gears

38b, 38a, respectively, and the two

stubs

44b and 44a are configured to differ in angular position by 180 degrees when the reciprocating saw is manufactured. Thus, the two

output members

23a and 23b always travel in opposite directions at any time. Starting from fig. 6a and 6b, it is assumed that the position of the stub 44b is at an angular position of 0 degrees, while the position of the stub 44a is at an angular position of 180 degrees. The saw blades (not shown in fig. 6a to 6 h) are at this time maximally offset from each other because the

output members

23a and 23b are offset from each other due to the positions of the

stubs

44a and 44 b.

During rotation of the

bevel gears

38a, 38b, their

respective stubs

44a, 44b also rotate about the same axis of rotation. However, since the

stubs

44a, 44b are received in corresponding grooves formed on the

output members

23a, 23b (e.g., the grooves 47b on the output member 23b), any movement of the

stubs

44a, 44b does not cause the

output members

23a, 23b to move in a vertical direction, which is a direction perpendicular to the longitudinal direction of the

output members

23a, 23 b. In contrast, movement of the

stubs

44a, 44b will cause the

output members

23a, 23b to move in a horizontal direction that is substantially parallel to the longitudinal direction of the

output members

23a, 23 b.

Next, if the bevel gear 38b is rotated in the clockwise direction and the bevel gear 38a is rotated in the counterclockwise direction, after rotating 90 degrees, the bevel gear 38b is moved to the position (90 degrees) shown in fig. 6c and the bevel gear 38a is moved to the position (90 degrees) shown in fig. 6 d. Subsequently, after rotating another 90 degrees, the bevel gear 38b moves to the position shown in fig. 6e (180 degrees), and the bevel gear 38a moves to the position shown in fig. 6f (0 degrees). This rotation continues so fig. 6g shows bevel gear 38b moving to the 270 degree position and fig. 6h shows bevel gear 38a moving to the position (270 degrees). Finally, after the last 90 degrees of rotation, the two

bevel gears

38a, 38b return to their positions shown in fig. 6b and 6a, and this means that the entire rotation cycle of the

bevel gears

38a, 38b is complete. The above-described process will be repeated for each rotation cycle of the

bevel gears

38a, 38b while the motor 30 remains running. As can be seen, the two

bevel gears

38a, 38b move about different rotational directions in each rotation cycle, and in most cases their angular positions are different. Only at certain points in time, as shown in fig. 6c and 6d and fig. 6g and 6h, are the

bevel gears

38a, 38b in exactly the same angular position. In particular, the locations of the

stubs

44a, 44b are the same at their 90 and 270 degrees locations, and opposite at 0 and 180 degrees. Together with the different rotational directions of the

bevel gears

38a, 38b, this causes the

saw blades

22a and 22b to move in anti-phase. When the

bevel gears

38a, 38b are in their angular positions of 0 degrees or 180 degrees, the

saw blades

22a, 22b are in their extreme/final positions (opposite to each other). When the

bevel gears

38a, 38b are in their 90 or 270 degree angular positions, the two saw

blades

22a, 22b meet at an intermediate position, but with different directions of movement (one forward and the other backward). In this way, the reciprocating saw is able to continuously output a reciprocating movement of the

saw blades

22a, 22b, wherein the two saw blades are always 180 degrees out of phase. Such operation does not require any intervention by the user, but only requires keeping the motor energized. Since the structure of the

saw blades

22a, 22b is described above in relation to fig. 12-14, the

saw blades

22a, 22b are slidably engaged with each other, so that the lateral distance between the

saw blades

22a, 22b does not change at any time, which ensures a stable and reliable sawing result.

Turning now to fig. 10a to 10d, wherein fig. 10a and 10c show the locked and unlocked positions, respectively, of the user actuated lever 50, and fig. 10b and 10d show the locked and unlocked positions, respectively, of the locking pin 48. In fig. 10a, the end of the user actuated lever 50 is shown where the closure 50c is closer to the clamp body 54. This is because in the state shown in fig. 10a, there is no user intervention, and the user actuation lever 50 is biased by the torsion spring 52 (which is an elastic member). At this point, the locking pin 48 is also in its locked position, as can be seen in fig. 10b, the trailing end 48c of the locking pin 48 occupies a portion of the L-shaped slot 54 e. Although fig. 10b and 10d do not show a saw blade, in the position of fig. 10b, the locking pin 48 will lock any saw blade that has been inserted into the L-shaped slot 54e by fitting with a hole (not shown) in the saw blade.

If the user operates the user actuated lever 50 in the position of figure 10a by overcoming the bias of the torsion spring 52, the user actuated lever 50 moves to the unlocked position shown in figure 10c, wherein the end of the user actuated lever 50 having the closure 50c moves further from the clamp body 54. Thus, the locking pin 48 also moves in the bore 54e away from the clamp body 54 and the tail end 48c leaves the L-shaped slot 54e as shown in fig. 10 d. Although fig. 10b and 10d do not show a saw blade, in the position of fig. 10d, the locking pin 48 will not prevent any saw blade that has been inserted into the L-shaped slot 54e from being released from the blade clamping module and then removed.

Turning to fig. 11 a-11 f, it is shown how the

saw blades

22a and 22b can be mounted to two

blade clamping modules

24a and 24b, respectively, of a reciprocating saw. First, the user must move the user actuation lever 50 to its unlocked position and, therefore, also move the locking pins 48 of the two

blade clamping modules

24a and 24b to their unlocked positions. This is shown in fig. 11a and 11b, where the tail end 48c of the locking pin 48 is shown away from the L-shaped slot 54e of the two

blade clamping modules

24a and 24 b. The two

blade clamping modules

24a and 24b are then ready to receive a saw blade. The user then positions the saw blade in the L-shaped slots 54e of the two

blade clamping modules

24a and 24b by aligning the L-shaped tabs (not shown) of the

saw blades

22a and 22b, respectively, as shown in fig. 11 c. At this point, however, the user has not yet released the user actuation lever 50 (still in its unlocked position), and thus the tail end 48c of the locking pin 48 has not yet locked the

saw blades

22a and 22b as shown in FIG. 11 d. Finally, after the user releases the user actuation lever 50, the user actuation lever 50 moves to its locked position, as shown in FIG. 11e, and the trailing end 48c of the locking pin 48 locks the

saw blades

22a and 22 b. Thus, the

saw blades

22a and 22b can move together with the

output members

23a and 23b to perform a sawing operation. To remove the

saw blades

22a and 22b from the reciprocating saw, the user simply reverses the process shown above in FIGS. 11 a-11 f. In any event, the locking pin 48 is adapted to move along the bore 54d into the L-shaped slot 54e or out of the L-shaped slot 54e as the user actuation lever 50 moves between its locked and unlocked positions.

Fig. 15 illustrates another embodiment of the present invention, in which an alternative drive module 121 for a reciprocating saw is shown. The difference with the transmission module shown in fig. 1 to 4 is that the transmission module 121 no longer contains a mating bevel gear design. Instead, there is only one bevel gear (not shown) in the transmission module 121, which is driven by a small bevel gear (not shown) in a manner similar to that described in fig. 1 to 4. Bevel gears directly drive output member 123a, but bevel gears also transfer their movement to cam 164, which is connected to another output member 123b, where cam 164 has an opposite cam profile to bevel gears so that output member 123b moves in anti-phase with output member 123 a.

Fig. 16a to 16d show another embodiment of the present invention showing an alternative saw tooth clamping module for a reciprocating saw. Such a serration clamping module may be used with a single serration reciprocating saw or a double serration reciprocating saw. The difference with the serrated clamping module shown in fig. 8 to 11f is that the serrated clamping module 224 shown in fig. 16a to 16d does not contain any user actuated levers. Instead, a lock button 225 is provided as the user actuation portion. The lock button 225 is adapted to move between a locked position as shown in fig. 16a and 16b and an unlocked position as shown in fig. 16c and 16 d. The lock button 225 has a substantially rod-like formation and includes a first end 225a that protrudes from the clamp body 254 of the serrated clamping module 224 when the lock button 225 is in its unlocked position. As shown in fig. 16b and 16d, the second end 225b of the lock button 225 is movably received within a channel (not shown) formed in the clamp body 254. The second end 225b is connected to a spring 259 (not shown in fig. 16 b) which in turn is connected to the inner wall of the clamping body 254. Since the width of the second end 225b is increased as compared to the first end 225a, a slope 225c is formed on the lock button 225 at the junction of the first end 225a and the second end 225 b. The ramp 225c is adapted to drive a ball 263, which is also received within the clamp body 254. The sphere 263 is adapted to move in a direction substantially perpendicular to the lock button 225. The ball 263 is further adapted to partially enter the L-shaped slot 254e which serves as a saw blade receiving slot and is formed on the clamp body 254 for insertion of an L-shaped tab on a saw blade therein.

In operation, the lock button 225 is normally biased by a spring 259 to its locked position, as shown in fig. 16a and 16b, in the absence of user intervention. At this point, the second end 225b is positioned against the ball 263, forcing the ball 263 partially into the L-shaped slot 254 e. If the current L-shaped slot 254e does not have any saw blade (not shown) mounted, the spheres 263 lock the saw blade that has been inserted into the L-shaped slot 54e by fitting into holes (not shown) in the saw blade. If the user wants to remove the blade from blade clamping module 224, he/she need only depress first end 225a of lock 225 and lock button 225 travels to its unlocked position, as shown in fig. 16 c-16 d. In this state, the first end 225a is retracted to the clamp body 254, and the second end 225b is moved to its travel end against the force of the spring 259. At this point, the ball 263 is no longer blocked by the second 225b and if the user pulls the mounted blade out of the L-shaped slot 254e, the ball 263 travels to the position shown in figure 16d so the blade can be removed. Thereafter, if the user re-inserts the blade/new blade, he/she need only remove the pressing force on the lock button 225 to return it to the locked position shown in fig. 16a and 16 b. During this process, the ramp 225c moves the ball 263 laterally with respect to the direction of movement of the locking button 225, and this returns the ball 263 to the position shown in fig. 16 b.

Accordingly, exemplary embodiments of the present invention have been fully described. Although the description refers to particular embodiments, it will be apparent to those skilled in the art that the present invention may be practiced with modification of these specific details. Therefore, the present invention should not be construed as being limited to the embodiments set forth herein.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only exemplary embodiments have been shown and described and do not limit the scope of the invention in any way. It is to be understood that any feature described herein may be used with any embodiment. The illustrative embodiments are not mutually exclusive or exclude other embodiments not enumerated herein. Accordingly, the present invention also provides embodiments that include combinations of one or more of the above illustrative embodiments. Modifications and variations may be made to the present invention as set forth herein without departing from the spirit and scope of the invention, and, accordingly, only such limitations should be imposed as are indicated by the appended claims.

For example, although the reciprocating saw shown in fig. 1-14 has two blade clamping modules intended to mount two blades to the reciprocating saw, in other variations it is entirely possible to have only one such blade clamping module in a reciprocating saw (which is a single blade saw).

Claims

1. A reciprocating saw, comprising:

a) a motor;

b) a first output member and a second output member adapted to be connected to a saw blade; the first output member and the second output member are further adapted to move independently of each other;

c) a first gear coupled with the first output member and a second gear coupled with the second output member; the first gear and the second gear rotate when driven by the motor, wherein the first gear and the second gear are bevel gears and are adapted to be simultaneously driven by bevel pinions;

wherein the first gear and the second gear are respectively formed with or connected to a first biasing member and a second biasing member; the first and second output members are movably coupled to the first and second biasing members, respectively, such that the first and second output members are adapted to perform reciprocating movements.

2. The reciprocating saw of claim 1, wherein the first gear and the second gear have the same axis of rotation; the first and second biasing members are offset from the axis of rotation.

3. The reciprocating saw as defined in claim 1, wherein said first output member and said second output member each include a recess; the first and second biasing members are received in grooves of the first and second output members, respectively, and are adapted to move in a direction perpendicular to a reciprocating direction of the first and second output members.

4. The reciprocating saw of claim 2, wherein the first biasing member and the second biasing member are located at different angular positions relative to the rotational axis during a portion of a rotational cycle.

5. The reciprocating saw of claim 1, wherein the first and second biasing members are stubs formed on the circular faces of the first and second gears, respectively.

6. A reciprocating saw, comprising:

a) a motor;

d) a blade clamping module disposed on the first output member and the second output member;

wherein the blade clamping module includes a user actuated lever connected to a locking pin; the locking pin is adapted to fit with a locking hole of the saw blade and lock the saw blade; the user actuation lever is adapted to move between a locked position, in which the locking pin locks the saw blade, and an unlocked position, in which the locking pin is spaced away from the saw blade.

7. The reciprocating saw of claim 6 wherein the blade clamping module further comprises a clamp body connected to the user actuated lever; the clamp body is formed with a saw blade receiving slot defined by two inner walls; the clamp body further formed with a hole communicating with the blade receiving slot from at least one of the inner walls; the locking pin is adapted to move along the bore into or out of the slot as the user actuated lever moves between the locked and unlocked positions.

8. The reciprocating saw of claim 7, wherein the blade receiving slot is substantially "L" shaped.

9. The reciprocating saw of claim 7 wherein the blade clamping module further comprises a resilient member connected to the user actuated lever; the user actuation lever is biased into its locked position by the resilient member.

10. The reciprocating saw as defined in claim 9, wherein the resilient member is a torsion spring including two legs; one of the legs is connected to the clamp body; the other leg is connected to the user actuation lever and the locking pin.

11. A reciprocating saw, comprising:

a) a motor;

c) a blade clamping module disposed on the first output member and the second output member;

wherein the blade clamping module comprises a locking button and a locking member; the locking button is adapted to move between a locked position, in which the locking button places the locking member in a position to lock the saw blade, and an unlocked position, in which the locking member is freely movable in a direction substantially perpendicular to the locking button.

12. The reciprocating saw of claim 11 wherein the lock button is formed with a ramp adapted to move the locking member to said position when the lock button is moved from its unlocked position to its locked position.

13. The reciprocating saw of claim 11 wherein the locking member is a ball.

14. The reciprocating saw of claim 11, wherein the blade receiving slot is substantially "L" shaped.

15. The reciprocating saw of claim 11, wherein the blade clamping module further comprises a resilient member connected to the lock button; the locking button is biased to its locking position by the resilient member.