CN109954937B

CN109954937B - Saw blade quick clamping device for reciprocating saw and reciprocating saw

Info

Publication number: CN109954937B
Application number: CN201711338744.4A
Authority: CN
Inventors: 王佳
Original assignee: Bosch Power Tools China Co Ltd
Current assignee: Bosch Power Tools China Co Ltd
Priority date: 2017-12-14
Filing date: 2017-12-14
Publication date: 2022-11-08
Anticipated expiration: 2037-12-14
Also published as: CN109954937A

Abstract

The application provides a saw blade quick-clamping device for a reciprocating saw and the reciprocating saw. The saw blade quick clamping device comprises a reciprocating rod driven by a transmission system of the reciprocating saw, and the reciprocating rod is provided with a saw blade seat for installing a saw blade; a clamping assembly releasably clamping the blade to the blade mount of the reciprocating bar; the clamping assembly comprises a clamping shell, the clamping shell comprises a cavity for accommodating the saw blade seat and is set to be capable of reciprocating along the direction vertical to the axial direction of the reciprocating rod, and when the clamping assembly is in a clamping position, the saw blade is clamped between the clamping shell and the mounting surface of the saw blade seat; and the driving component is arranged in the cavity of the clamping shell to drive the clamping shell to move in a reciprocating manner. The rapid mounting and dismounting of the saw blade are realized through the matching movement of the clamping shell and the driving part; fasteners are not needed for connecting all the parts, and the assembly mode is simple and quick; each part has simple structure and easy processing, and is suitable for various electric reciprocating saws.

Description

Saw blade quick clamping device for reciprocating saw and reciprocating saw

Technical Field

The present application generally relates to the field of rapid tooling fixtures. And more particularly to a blade quick-clamping device for an electric reciprocating saw and a reciprocating saw having such a blade quick-clamping device.

Background

Electric reciprocating saws are widely applied to industries such as automobiles, decoration, leather and the like, and mainly comprise a jig saw, a saber saw and the like, and linear or curve cutting is carried out on workpieces such as wood, metal, plastic, rubber and the like through the reciprocating motion of a saw blade. The clamping mechanism of the saw blade of the reciprocating saw is generally of two types, namely a common type and a quick type, the common type clamping mechanism is generally used for clamping the saw blade and the reciprocating rod by using a fastening element, and the mounting and dismounting operations are complicated and time-consuming. Quick clamping mechanisms allow for quick clamping or release of the saw blade, are convenient to operate, but are generally complex in construction and assembly.

Patent document US6112420a discloses a saw blade clamping device for a reciprocating saw, wherein the saw blade is held on a bottom projection of a cavity of a housing by a rotatable clamping handle, and a plate for clamping is provided between the clamping handle and the bottom of the cavity of the housing. In addition, the clamping device fixes the fastening piece through the hole on the shell and the threaded hole on the reciprocating rod. However, in practical applications, due to the limitation of the manufacturing process, the bottom protrusion of the housing is not easy to form, and the requirement of fixing the saw blade cannot be satisfied well only by the bottom protrusion of the housing. In some solutions, it is necessary to provide a fixing pin on the reciprocating bar for fixing the blade, and the fixing pin on the reciprocating bar is usually required to pass through a hole in the blade holder having a certain thickness and through a hole in the bottom of the housing before it can be engaged with the blade. The cantilever length of the pin is thus significantly increased, resulting in the pin root being subjected to a significant stress concentration, which tends to break at the root and fail during cutting. Therefore, the existing clamping device has the defects of various parts, complex installation, insufficient strength and the like.

Disclosure of Invention

The present application aims to solve the above-mentioned problems of the prior art and to provide an improved quick clamping device for saw blades, which enables self assembly in a simple manner and allows quick and easy mounting and dismounting of the saw blade. Another object of the present application is to provide a saw blade quick clamping device that allows saw blades of different thicknesses to be securely held while avoiding damage to components in the quick clamping device, and extending product life.

To this end, according to one aspect of the present application, there is provided a saw blade quick clamping device for a reciprocating saw, comprising: a reciprocating lever driven by a transmission system of the reciprocating saw and having a blade holder for mounting a saw blade; a clamping assembly releasably clamping a saw blade to a blade mount of the reciprocating bar; wherein, the centre gripping subassembly includes: a clamping housing including a cavity to receive the blade holder and configured to reciprocate in a direction perpendicular to an axial direction of the reciprocating rod, wherein in a clamping position, the saw blade is clamped between the clamping housing and a mounting surface of the blade holder; and the driving component is arranged in the cavity of the clamping shell to drive the clamping shell to move in a reciprocating manner.

The present application may further include any one or more of the following preferred forms according to the above technical idea.

In certain preferred forms, the drive member comprises a cam pivotally mounted within the cavity of the clamp housing and arranged to pivotally drive the clamp housing to reciprocate.

In certain preferred forms, the cam is arranged to pivotally urge a surface of the blade holder opposite the mounting surface of the blade holder to drive the clamp housing to reciprocate.

In certain preferred forms, the clamping assembly further comprises a fixing pin which is a close fit with a mounting hole provided in the blade mount and has a protruding end which protrudes through the mounting hole to engage with a fixing hole in a mounting shank of a saw blade.

In certain preferred forms, the clamp housing is provided with an opening that is substantially aligned with a mounting hole in the blade mount.

In certain preferred forms, the blade holder is formed with a generally T-shaped mounting slot which is form-fit with a mounting shank of the saw blade.

In certain preferred forms, the clamp assembly further comprises a bearing pin by which the drive member is pivotally mounted within the cavity of the clamp housing.

In certain preferred forms, the clamp assembly further includes a resilient element that is sleeved on the bearing pin and abuts the clamp housing and the drive component, respectively, to deflect the drive component.

In certain preferred forms, the clamp housing is provided in a generally U-shape having a bottom wall and two side walls extending perpendicularly from the bottom wall, the side walls being guided for movement by shoulders formed on the blade holder, the spacing between the two side walls being substantially equal to the width of the mounting shank of the saw blade.

In certain preferred forms, the distance between the free ends of the two side walls of the clamping shell is greater than or equal to the distance between the connecting ends of the two side walls and the bottom wall.

According to another aspect of the present application there is provided a reciprocating saw including a saw blade quick clamping arrangement as described above.

Compare in current saw blade clamping device, the saw blade of this application presss from both sides device soon has following advantage at least: the rapid mounting and dismounting of the saw blade can be achieved by the co-operating movement of the clamping housing and the drive member, preferably a cam; the saw blade is clamped between the clamping shell and the saw blade seat of the reciprocating rod, so that the clamping effect is stable and reliable; fasteners such as screws, bolts and the like are not needed for connecting all the parts, and the assembly mode is simple and quick; each part has simple structure, easy processing, wide application and is suitable for various electric reciprocating saws.

Drawings

Other features and advantages of the present invention will be better understood by the following detailed description of the preferred embodiments when considered in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic view of a saw blade quick-clamping device according to a preferred embodiment of the present application;

FIG. 2 is an enlarged schematic view of the clamping assembly of FIG. 1;

FIG. 3 is an exploded view of the quick clamping arrangement of the saw blade of FIG. 1;

FIG. 4a is a schematic view of the reciprocating lever of the quick-release device of the saw blade of FIG. 1, and FIG. 4b is a schematic view of the reciprocating lever from another angle;

FIG. 5a is a schematic perspective view of a clamp housing of the saw blade quick clamping device of FIG. 1, FIG. 5b is a schematic top view of the clamp housing of FIG. 5a, FIG. 5c is a schematic front view of the clamp housing of FIG. 5a, and FIG. 5d is a schematic side view of the clamp housing of FIG. 5 a;

FIG. 6 is a schematic view of a cam in the quick-clamping device of the saw blade of FIG. 1;

FIG. 7 is a schematic view of a resilient member in the quick-clamping arrangement of the saw blade of FIG. 1;

FIG. 8a is a view similar to FIG. 4a showing a state in which a reciprocating lever is coupled to a fixing pin, and FIG. 8b is a partially enlarged sectional view of FIG. 8 a;

FIG. 9 is a schematic view of the quick clamping device of the saw blade of FIG. 1 in a clamped state;

FIG. 10a is a schematic cross-sectional view of FIG. 9, and FIG. 10b is a schematic cross-sectional view of the saw blade quick clamping device in a released state;

fig. 11a is a schematic view of a blade holder of a reciprocating bar according to another embodiment, and fig. 11b is a schematic view of the reciprocating bar of fig. 11a with a blade mounted thereto.

Detailed Description

The practice and use of the embodiments are discussed in detail below. It should be understood, however, that the description herein of specific embodiments is merely illustrative of specific ways to make and use the disclosure, and is not intended to limit the scope of the disclosure. The description herein of the structural positions of the respective components, such as the directions of upper, lower, top, bottom, etc., is not absolute, but relative. When the respective components are arranged as shown in the drawings, these direction expressions are appropriate, but when the positions of the respective components in the drawings are changed, these direction expressions are changed accordingly.

As used herein, "reciprocating saw" encompasses power tools in which the saw blade cuts in a reciprocating motion, including but not limited to jig saws. With respect to the blade shape of the reciprocating saw, the blade is generally classified as a blade having a fixing hole in a mounting shank, or a blade in which the mounting shank is formed in a substantially T-shape. The application provides a saw blade presss from both sides device soon can be applicable to above-mentioned saw blade to provide the loading and unloading firm fast to the saw blade.

Referring first to fig. 1, according to the concept of the present application, a blade quick clamping device includes a reciprocating bar 10 and a clamping assembly 30, the reciprocating bar 10 is driven by a driving system (not shown) of a reciprocating saw and has a blade holder to which a blade 20 is mounted, and the clamping assembly 30 releasably clamps the blade 20 to the blade holder of the reciprocating bar 10, so that an output power of the driving system can be transmitted to the blade 20 by means of the reciprocating bar 10 to cut a material.

In a preferred embodiment shown in fig. 2 and 3, the clamping assembly 30 comprises a clamping housing 31 and a cam 32 as a preferred example of the driving means, wherein the clamping housing 31 comprises a cavity to receive the blade holder 11 of the reciprocating lever and the cam 32. The clamp housing 31 is provided to be capable of reciprocating in a direction perpendicular to the axial direction of the reciprocating lever 10, and clamps the saw blade 20 between the clamp housing 31 and the mounting surface of the blade holder 11 in the clamping position. Advantageously, a cam 32 is provided to effect the reciprocal movement of the clamp housing 31, by being pivotally mounted within the cavity of the clamp housing 31, thereby pivotally driving the clamp housing 31 to move.

The structure and assembly of the components of the preferred embodiment are described in detail below in conjunction with fig. 4 a-8 b.

As shown in fig. 5a to 5d, the clip housing 31 is provided in a substantially U-shape, including a bottom wall 313 and

side walls

311, 312 extending perpendicularly from the bottom wall 313, thereby forming a cavity. The spacing D1 between the

side walls

311, 312 is approximately equal to the width of the mounting shank of the saw blade 20. Advantageously, shoulders are formed on the blade seat 11 of the reciprocating lever 10, as shown in fig. 4b, which shoulders are formed at both side ends of the blade seat 11 and preferably have a lower shoulder 15 and an upper shoulder 16, so that a guide-groove-like structure is formed between the shoulders, so that the upper and lower end faces of the

side walls

311, 312 of the clamping housing 31 can be snapped into and guided for movement via the guide grooves. The blade holder 11 and the reciprocating rod 10 may be integrated or may be divided into two separate parts and connected by welding, riveting, screwing, or the like.

The cam 32, which can be seen in particular in fig. 6, is pivotally mounted in the cavity of the clamping housing 31 by means of a bearing pin 33 (fig. 3). For this purpose, the holding housing 31 has support holes 315, 316 formed in its two

side walls

311, 312, respectively, and the cam 32 has corresponding through holes 324 formed therein for the support pins 33 to pass through. The clamping housing 31 in its clamping position clamps the saw blade 20 between the bottom wall 313 and the mounting surface of the blade holder 11 of the reciprocating lever 10. As shown in fig. 4a, the side of the blade holder 11 facing the bottom wall 313 of the clamping housing 31 is the mounting surface 13, and the cam 32 is preferably arranged to pivotally push against the surface 14 of the blade holder 11 opposite the mounting surface 13, thereby driving the clamping housing 31 to reciprocate. It will be appreciated that the reciprocating movement of the clamping housing 31 encompasses an initial position in which the saw blade 20 is not clamped, a clamping position in which the saw blade 20 is clamped between the bottom wall 313 of the clamping housing 31 and the mounting surface 13 of the blade holder 11, and a release position in which the saw blade 20 can be attached and detached. When the clamping housing 31 is in the initial position, its bottom wall 313 abuts the mounting surface 13 of the blade holder 11.

The driving action of the cam 32 on the clamping housing 31 is preferably reset, in other words when the cam 32 is forced to move the clamping housing 31 to the release position, once the saw blade has been removed and replaced, the removal of the force on the cam should enable the cam to reset and move the clamping housing 31 to the clamping position, i.e. the cam has a self-locking function. The resilient element 34 shown in fig. 7 effectively fulfils this function. In the illustrated embodiment, the elastic element 34 is, for example, a torsion spring, which is sleeved on the supporting pin 33, and the two

end portions

341 and 342 abut against a first positioning hole 317 formed on the side wall 311 of the clamping housing 31 and a second positioning hole 325 formed on the cam 32, respectively, to deflect the cam 32 for automatic return. In addition, through the arrangement, enough clamping force can be kept to avoid the saw blade from loosening or falling off in the cutting process of the saw blade, and the clamping reliability is further ensured.

The spacing between the two

side walls

311, 312 of the clamp housing 31 is preferably kept uniform in view of the component size and the assembly compactness. However, in order to obtain a good spring force, which makes the operation more comfortable and the clamping more reliable, it is advantageous to arrange the spring element 34 with a certain length. Thus, as best shown in fig. 5b, one of the side walls 311 of the clamping shell 31 has a free end bent such that the distance D2 between the free ends of the two

side walls

311, 312 is greater than the distance D1 between the connecting ends of the two

side walls

311, 312 and the bottom wall 313. In this way, the clamp housing 31 has enough space to accommodate the cam 32 and the elastic member 34, so that the components can be more easily fitted into the cavity of the clamp housing 31.

In the embodiment shown in fig. 6, the cam 32 has a main body portion 321 and an arc portion 322, the main body portion 321 is provided with the above-described through hole 324 through which the support pin 33 passes and the second positioning hole 325 through which the one end portion 342 of the elastic member 34 passes, and is provided to abut against the end surface 323 of the elastic member 34. The inner surface of the curved portion 322 forms a space for receiving the resilient member 34, while the outer surface forms a curved surface for pushing against the surface 14 of the blade holder 11, as will be described in more detail below. In addition, cam 32 has a handle 326 that can be toggled by an operator to effect loading and unloading of the saw blade.

In the case of the saw blade 20 shown in fig. 3, that is, the saw blade 20 has a fixing hole 21 in the mounting shank, the clamping assembly further includes a fixing pin 35, the fixing pin 35 is tightly fitted into the mounting hole 12 provided in the blade holder 11, and has a protruding end protruding out of the mounting hole 12 to be fitted into the fixing hole 21 in the mounting shank of the saw blade 20. As shown in connection with fig. 8a and 8b, one end 356 of the securing pin 35 is inserted into the mounting hole 12 in the blade holder 11 and remains locked, and the other protruding end 355 protrudes over a length L, which is approximately the thickness of a conventional saw blade, for example 1.3mm. Thus, the protruding end of the fixing pin is attached to the thickness of the saw blade from the root, so that excessive stress concentration on the root of the fixing pin 35 is avoided, and the fixing pin is prevented from being broken or broken.

An opening 314 is provided in the bottom wall 313 of the clamp housing to clear the securing pin 35, the opening 314 being generally aligned with the mounting hole 12 in the blade holder, as shown in figure 5 a. When the quick clamping device is used for clamping a saw blade with the thickness smaller than L, the fixing pin can extend out of the fixing hole 21 of the saw blade and can reach the position of the opening 314, so that the bottom wall of the clamping shell is avoided, the bottom wall of the clamping shell is always tightly attached to the side surface of the saw blade, and the saw blade is reliably clamped.

In addition, the opening 314 may also serve as a viewing window for an operator to visually inspect whether the securing hole 21 of the blade is positioned on the securing pin 35 when the blade is being attached and removed. The opening 314 is not limited to the round hole shape shown in the drawings, and other shapes such as a square shape slightly larger than the size of the fixing pin 35 are also possible.

When the saw blade 20 is clamped by the blade snapping arrangement of the present application, see fig. 9 and 10a, the arcuate face of the cam presses against the face 14 of the blade holder and is held in a state in which the clamping housing 31 is moved into the clamping position by the resilient member 34. At this time, the fixing hole 21 of the saw blade 20 is positioned in cooperation with the protruding end 355 of the fixing pin and clamped between the bottom wall 313 of the clamp housing 31 and the mounting surface 13 of the blade holder 11. The arcuate face of the cam includes an arcuate segment 327 having an initial portion 328 and a terminal portion 329, the arcuate segment 327 preferably being configured such that the spacing between the bottom wall of the clamp housing and the mounting face of the blade holder is capable of clamping and releasing most saw blades of different thickness sizes (e.g. 0.8mm to 2.0 mm), wherein the clearance required to release the saw blade is approximately: the L + blade thickness is, for example, such that the pitch is in the range of 0 to 4.0 mm. When the cam pivots until the start 328 presses against the surface 14 of the blade holder 11, as shown in fig. 10b, the clamping housing is in the maximum release position; and the cam is pivoted until the stop 329 is pressed against the surface 14 of the blade holder 11, the clamp housing is in the maximum clamping position.

When it is desired to remove and replace the saw blade 20, as shown in fig. 10b, the operator can toggle the handle 326 of the cam to pivot the cam downwardly about the support pin 33 to move the clamping housing toward its release position, such as to the maximum release position shown in the figure, and then can see through the opening 314 in the clamping housing whether the saw blade 20 has been removed and whether a new saw blade has been accurately positioned on the protruding end 355 of the fixing pin 35. Then, the force applied to the cam is removed, and the cam automatically returns due to the action of the elastic member, so that the grip housing is rapidly moved to the grip position. Therefore, the handle that the quick-clamping device accessible of this application was stirred the cam utilizes the spring force to produce locking effect in the twinkling of an eye, has accelerateed the loading and unloading of saw blade.

Fig. 11a and 11b show another embodiment of a reciprocating lever particularly suitable for use with a saw blade of a jigsaw in which the mounting shank is formed in a generally T-shape. In this embodiment, the blade holder 110 of the reciprocating lever is formed with a substantially T-shaped mounting groove 120, and the mounting groove 120 is form-fitted to the mounting shank 210 of the saw blade 200. For example, a boss 121 is formed on the mounting groove 120, and the boss 121 can abut against a side end protrusion 211 on the mounting shank 210 of the saw blade 200, thereby positioning and fixing the saw blade 200. When the saw blade 200 is installed, a similar operation to that described above can be used, with the saw blade 200 being placed directly into the mounting slot 120 after the clamping housing is moved to the release position, and once the force applied to the cam is removed, the clamping housing is moved to the clamping position to clamp the saw blade 200 between the bottom wall of the clamping housing and the mounting surface of the blade holder 110. It will be appreciated that in such an embodiment, the bottom wall of the clamping housing may be provided without openings, and the reciprocating rod may not require a fixed pin.

From the above summary of the saw blade quick clamping device of the present application, it can be seen that the present application enables easy removal, replacement of the saw blade without the aid of any additional tools; the saw blade has good positioning performance and stable installation, and is not easy to fall off even in the high-speed reciprocating motion and cutting process; particularly, the saw blade quick clamping device can realize the positioning and connection of each part only by simple insertion without any additional parts or structures such as threaded connection, welding or riveting and the like, thereby simplifying the manufacturing and assembling; in addition, each part is reliably implemented, the phenomenon of breakage or even breakage caused by overload can not occur, and the service life of the product is ensured.

It should also be noted that the embodiments shown in fig. 1-11 b only show the main implementing units or components of the saw blade quick clamping device according to the present application, the shape and arrangement of the units or components is merely illustrative and not limiting, and the quick clamping device may alternatively or additionally take on units or components of other shapes and sizes without departing from the spirit and scope of the present application. In addition, in each embodiment, the saw blade seat of the reciprocating lever may be formed by extrusion molding, welding, etc., the clamping housing and the cam may be formed by injection molding, and the type, position, number, etc. of the elastic element and the cam may be modified according to actual needs.

The technical content and technical features of the present application have been disclosed above, however, it is understood that various changes and modifications of the disclosed concept can be made by those skilled in the art under the inventive concept of the present application, and all fall within the protective scope of the present application. The above description of embodiments is intended to be illustrative, and not restrictive, and the scope of the application is defined by the appended claims.

Claims

1. A blade quick clamp device for a reciprocating saw, comprising:

a reciprocating lever (10), said reciprocating lever (10) being driven by a transmission system of the reciprocating saw and having a blade seat (11) for mounting a blade (20);

a clamping assembly (30) releasably clamping a saw blade (20) to a blade mount (11) of the reciprocating bar (10);

characterized in that said clamping assembly (30) comprises:

a clamping housing (31), the clamping housing (31) comprising a cavity to receive the blade holder (11) and being arranged to be reciprocally movable in a direction perpendicular to the axial direction of the reciprocating rod (10), wherein in a clamping position a saw blade (20) is clamped between the clamping housing (31) and a mounting surface (13) of the blade holder (11);

a driving component installed in a cavity of the clamping shell (31) to drive the clamping shell (31) to move in a reciprocating manner.

2. Saw blade quick clamping device according to claim 1, wherein the drive means comprises a cam (32), the cam (32) being pivotably mounted within a cavity of the clamping housing (31) and being arranged to pivotally drive the clamping housing (31) to reciprocate.

3. Saw blade quick clamping device according to claim 2, wherein the cam (32) is arranged to pivotally push against a surface (14) of the blade holder (11) driving the clamping housing (31) to move to and fro, said surface (14) being opposite to the mounting surface (13) of the blade holder (11).

4. Saw blade quick clamping device according to claim 3, characterized in that the clamping assembly (30) further comprises a fixing pin (35), the fixing pin (35) being tightly fitted with a mounting hole (12) provided on the saw blade holder (11) and having a protruding end (355) protruding out of the mounting hole (12) to cooperate with a fixing hole (21) on the mounting shank of the saw blade (20).

5. Saw blade quick clamping device according to claim 4, characterized in that the clamping housing (31) is provided with an opening (314), which opening (314) is substantially aligned with the mounting hole (12) in the saw blade holder (11).

6. Saw blade snap-action device according to claim 3, characterized in that the blade holder (11) is formed with a substantially T-shaped mounting groove (120), which mounting groove (120) is form-fit with a mounting shank (210) of the saw blade (20).

7. Saw blade quick clamping device according to any one of claims 1 to 6, wherein the clamping assembly (30) further comprises a bearing pin (33), the drive member being pivotally mounted in a cavity of the clamping housing (31) by means of the bearing pin (33).

8. Saw blade quick clamping device according to claim 7, wherein the clamping assembly (30) further comprises a resilient element (34), the resilient element (34) being sleeved on the support pin (33) and abutting the clamping housing (31) and the drive part, respectively, to deflect the drive part.

9. Saw blade snap-action device according to claim 8, wherein the clamping housing (31) is provided substantially in a U-shape with a bottom wall (313) and two side walls (311, 312) extending perpendicularly from the bottom wall (313), the side walls (311, 312) being guided in movement by shoulders (15, 16) formed on the saw blade holder (11), the distance between the two side walls (311, 312) being substantially equal to the width of the mounting shank of the saw blade (20).

10. Saw blade quick-clamping device according to claim 9, characterized in that the distance between the free ends of the two side walls (311, 312) of the clamping housing (31) is greater than or equal to the distance between the connecting ends of the two side walls (311, 312) and the bottom wall (313).

11. A reciprocating saw, characterized in that the reciprocating saw comprises a saw blade snap-in arrangement according to any one of the preceding claims.