WO2014117681A1

WO2014117681A1 - Power tool

Info

Publication number: WO2014117681A1
Application number: PCT/CN2014/071326
Authority: WO
Inventors: 王家达; 徐静涛; 钟红风; 张士松
Original assignee: 苏州宝时得电动工具有限公司
Priority date: 2013-01-30
Filing date: 2014-01-24
Publication date: 2014-08-07
Also published as: CN103963024A; CN103963024B

Abstract

The present invention provides a power tool, which comprises an output shaft used for mounting and driving a working head to work, a fastener used for fixing the working head on the output shaft, a locking piece that moves between a locking position and a release position, an elastic element used for enabling the locking piece to always face the locking position and a retainer that can be selected to cooperate with the locking piece, wherein the locking piece is used for locking and releasing the working head. Such setting enables an operator to press the fastener only so that the fastener pushes the retainer to cause the retainer to get away from cooperation with the locking piece, while the locking piece moves to the locking position under an action of the elastic element and locks a rod part of the fastener to the output shaft, so that the working head is easily mounted on the output shaft. At the release position, the retainer cooperates with the locking piece so that the fastener can be easily dismounted from the output shaft, improving operation convenience.

Description

Power tools

The invention relates to a power tool.

Background technique

A working head in a power tool, such as a circular saw blade, is typically driven by a rotating output shaft that is coupled to the motor of the power tool. In many cases, the circular saw blade has a hole through the center that houses the output shaft. One end of the output shaft on which the circular saw blade is mounted is internally threaded. When installing, place the saw blade on the output shaft, extend the fastening bolt through the hole in the saw blade into the thread of the output shaft, and then tighten the fastening bolt with a wrench to fix the circular saw blade on the output shaft. Similarly, the circular saw blade can be removed by loosening the fastening bolts with a wrench and removing the fastening elements from the output shaft. It can be seen that the conventional structure of mounting the working head on the output shaft is cumbersome and time consuming.

Therefore, it is necessary to provide an improved power tool to solve the above problems.

Summary of the invention

The technical problem to be solved by the present invention is to provide a power tool capable of assembling and disassembling a working head conveniently and quickly.

In order to solve the above problems, the present invention provides a power tool including: an output shaft for mounting and driving a working head, including a longitudinally extending receiving hole; and a fastener for fixing the working head The output shaft includes a rod portion extending into the receiving hole; a locking member moving between the locking position and the releasing position for locking and releasing the fastener; Urging the locking member to always face the locking position; the stopping member is selectably engageable with the locking member; in the releasing position, the locking member cooperates with the locking member to be capable of outputting from the output Removing the fastener from the shaft; the fastener pushes the stopper during the release position to the locking position, causing the stopper to disengage from the locking member, The locking member is moved to the locked position by the elastic member; in the locked position, the locking member locks the fastener to the output shaft.

According to the power tool disclosed by the present invention, the fastener is pushed by the operator, so that the fastener pushes the stopper to move, and the stopper is disengaged from the engagement with the locking member, and the locking member is disengaged and cooperates with the stopper. After being moved by the elastic member to the locking position, the fastener is locked on the output shaft, so that the working head can be easily mounted on the output shaft; the lock is matched with the locking member, and the lock is locked The clamping member is held in a release position in which the fastener can be easily removed from the output shaft, improving operation Convenience.

Preferably, the stopper is selectively engageable with the locking member along an axial direction of the output shaft. Preferably, one of the stopper and the locking member is provided with a fitting groove, and the other of the stopper and the locking member is provided with a fitting portion, the fitting groove and The mating portions are mated.

Preferably, the stopper is provided with a groove that cooperates with the fastener, and the groove is semicircular or curved.

Preferably, the rod portion includes an abutting surface perpendicular to an axis of the output shaft, and the locking member includes a through hole through which the abutting surface passes and a locking functioning with the abutting surface The limiting surface is provided with a limiting hole through which the abutting surface cannot pass, wherein the through hole is in communication with the limiting hole.

Preferably, the output shaft is connected with a mounting seat, and one of the mounting seat and the locking member is provided with a guiding groove inclined with respect to an axis of the output shaft, and the mounting seat and The other of the locking members is provided with a guiding portion, and the guiding groove cooperates with the guiding portion.

Preferably, the mounting seat includes first and second split seats, and the guiding slot is formed by the first and second split seats.

Preferably, the power tool further includes a driving member that urges the locking member to move, the driving member includes a first engaging surface that engages with the locking member, and the first engaging surface passes when the driving member moves Driving the locking member to move.

Preferably, the locking member is provided with a second engaging surface matching the first engaging surface, and the second engaging surface is inclined with respect to an axis of the output shaft.

Preferably, a spring is provided between the stopper and the driving member.

Preferably, the driving member is disposed on the output shaft in an axial direction of the output shaft. Preferably, the rod portion is provided with a tapered end that cooperates with the stopper.

Preferably, the receiving hole is provided with a threaded hole at an end close to the saw blade.

Another technical problem to be solved by the present invention is to provide an operation method capable of quickly and easily loading and unloading a work head to a power tool.

In order to solve the above problems, the present invention provides an operating method for loading and unloading a working head to a power tool, the power tool comprising: an output shaft for mounting and driving the working head, including a mounting portion mated with the working head and a longitudinally extending receiving hole; a fastener for fixing the working head to the output shaft, comprising a pressing plate coupled to the working head and a rod extending into the receiving hole; the locking member, in the locking Moving between a position and a release position for locking or releasing the stem; the method of operation comprising the steps of: a) locating the working head between the mounting portion and the pressure plate, Rod Passing through the working head and extending into the receiving hole; b) pressing the pressing plate in the axial direction of the output shaft to move the locking member and clamp the fastener.

In the operation method disclosed by the present invention, the operator can easily mount the working head on the output shaft without the need of an external auxiliary tool, and the operation is very convenient.

Preferably, the power tool further includes a retaining member selectively engageable with the locking member, and an elastic member for causing the locking member to always face the locking position. In step b), the tightening The fastener pushes the stop member to cause the stop member to disengage from the locking member, the locking member moving under the action of the elastic member and clamping the rod portion.

Preferably, in step b), the stopper is disengaged from the locking member along the axial direction of the output shaft.

Preferably, in step b), the elastic member urges the locking member to move in a direction inclined with respect to an axis of the output shaft.

Preferably, the power tool further includes a driving member movably disposed on the output shaft, the operating method further comprising the steps of: c) pressing the driving member to drive the locking member to move to release the tightness firmware.

Preferably, in step C), the driving member is pressed in the axial direction of the output shaft.

Preferably, in step C), the driving member drives the locking member to move in a direction inclined with respect to an axis of the output shaft.

Preferably, in step C), the stopper is movably engaged with the locking member along an axial direction of the output shaft.

Preferably, a spring is provided between the stopper and the driving member.

Preferably, in step C), the stopper pushes the fastener under the action of the spring. Another technical problem to be solved by the present invention is to provide an operation method capable of quickly and easily removing the work head from the power tool.

In order to solve the above problems, the present invention provides an operating method for loading and unloading a working head to a power tool, the power tool comprising: an output shaft for mounting and driving the working head; and a fastener for fixing the working head On the output shaft; a locking member that moves between a locked position and a released position for locking or releasing the fastener; a driving member movably disposed on the output shaft; The method comprises the steps of: a) pressing the drive member, driving the locking member to move to release the fastener; b) removing the working head. In the operating method disclosed by the present invention, the operator only needs to press the driving member to drive the locking member to move to release the fastener, so that the fastener can be easily removed from the output shaft, which improves the convenience of operation.

Preferably, in step a), the driving member is pressed in the axial direction of the output shaft.

Preferably, in step a), the driving member drives the locking member to move in a direction inclined with respect to an axis of the output shaft.

Preferably, the power tool includes a stop member that is selectable to cooperate with the locking member.

Preferably, the stopper cooperates with the locking member along an axial direction of the output shaft.

Preferably, a spring is provided between the stopper and the driving member.

Preferably, the stopper pushes the fastener under the action of the spring

DRAWINGS

The invention will be further described in detail below with reference to the accompanying drawings.

Figure 1 is a perspective view of a power tool of the present invention.

Figure 2 is a partial perspective view of the power tool of Figure 1 with the housing removed.

3 is an exploded perspective view of the quick clamping device of the power tool of the present invention.

4 is an exploded perspective view of another perspective of the quick clamping device of the power tool of the present invention.

Figure 5 is a partial perspective view of the quick-clamping device of the power tool of the present invention, in which case the locking member does not clamp the firmware.

Figure 6 is a partial perspective view of the quick-clamping device of the power tool of the present invention, in which case the locking member clamps the fastener.

Figure 7 is a cross-sectional view of the quick-clamping device of the power tool of the present invention with the drive member in an initial position. Figure 8 is a cross-sectional view of the quick-clamping device of the power tool of the present invention with the locking member in the released position. Figure 9 is a cross-sectional view of the quick-clamping device of the power tool of the present invention with the locking member in the locked position. Figure 10 is a perspective view of another angle of the power tool of the present invention.

In the picture:

3 0. Small electric circular saw 3 2. Housing 34. Motor

3 6. Drive assembly 3 8. Circular saw blade 4 0. Output shaft

4 2. Front of the housing 4 4. Rear of the housing 4 6 . Middle of the housing

4 8. Power cord 4 9. Switch 5 0. Fasteners 52. Mounting section 54. 孑L 56. Center hole

58. Boss 60. Connector 62. Raised

64. Platen 65. Button 66. Rod

68. Fixed end 70. Free end 72. Step

74. Abutment surface 76. Locking member 78. Elastic element

80. Stopper 81. Mounting bracket 82. First split seat

84. Second split seat 86. Mounting sleeve 88. First guide surface

90. Second guiding surface 92. Limiting groove 94. Main body

96. Through hole 98. Limit hole 100, . Locking surface

102. Limiting portion 104. Projection portion 106, . Limiting surface

108. abutment surface 110. guiding portion 112. mating portion

114, . with groove 116, . body 118. support

120. Groove 122 .U-shaped groove 124. .Spring

126. drive member 128. operation portion 130, . meshing portion

132. Guide portion 134. Guide groove 136, .

138. Second mating surface 139. Threaded hole 140, . Protective cover

142, . hole

detailed description

The present invention relates to a power tool, and more particularly to a structure and method for mounting a work head on a power tool. The power tool may be an electric circular saw, a small electric circular saw, an oscillating machine, an angle grinder, a diagonal saw, etc.; and the working head may be a straight saw blade, or may be a circular saw blade, an abrasive disc, a scraper, etc. Other accessories.

In the present embodiment, a small electric circular saw is cited to illustrate the inventive concept of the present invention.

Referring to Figures 1 and 2, a small electric circular saw 30 includes a housing 32, a motor 34 housed within the housing 32, a transmission assembly 36 coupled to the motor 34 for transmitting power, and driven by the transmission assembly 36. The output shaft 40 of the circular saw blade 38 is mounted (as shown in Figure 3). In the description of the present invention, unless otherwise stated, directional terms such as front, back, left, right, up and down, etc., are relative to the direction in which the small electric circular saw is normally used, as defined by the advancement of a small electric circular saw. The direction is the front, and the direction opposite to the forward direction of the small electric circular saw is the rear.

The housing 32 includes a housing front portion 42, a housing rear portion 44, and a connection housing front portion 42 and a housing rear The central portion 46 of the portion 44 of the portion 44. Here, the central portion 46 of the housing is a handle grip. Of course, the handle grip can also be provided at other portions of the housing 32 or separately.

In the present embodiment, the motor is the motor 34, and the motor 34 transmits power to the output shaft 40 through the transmission assembly 36, thereby driving the circular saw blade 38 for cutting work. As is well known to those skilled in the art, the motor can also be a pneumatic motor, a hydraulic motor, or the like. The motor 34 is housed in the rear portion 44 of the housing, and the motor 34 is electrically connected to the power line 48 so as to be connectable to an AC power source (not shown). Of course, the motor 34 can also be powered by a DC battery. The small electric circular saw 30 further includes a switch 49, and the switch 49 is electrically connected to the motor 34 for controlling the opening and closing of the motor 34.

As shown in Fig. 3, the output shaft 40 extends in the longitudinal direction and has an axis X. A circular saw blade 38 is attached to the output shaft 40 by a fastener 50 at one end. The output shaft 40 includes a mounting portion 52 that mates with the circular saw blade 38 and a receiving hole 54 that extends in a human direction.

The circular saw blade 38 has a central hole 56 formed therein, and the output shaft 40 is provided with a boss 58 that cooperates with the central hole 56. In the present embodiment, the size of the center hole 56 is larger than the size of the boss 58. Therefore, the small electric circular saw 30 is also provided with a connecting member 60. The connecting member 60 is provided with four cylindrical projections 62 for engaging with the four arcuate corners of the center hole 56. When installed, the four cylindrical projections 62 of the connector 60 pass through the mounting portion 52 and cooperate with the four arcuate corners 6 of the central bore 5 to securely mount the circular saw blade 38 on the output shaft 40. At the same time, the power is better transmitted. Of course, it will be readily understood by those skilled in the art that the boss 58 can be matched or not matched to the central aperture 56 in shape, size, or both. The cross section of the center hole 56 can be of various shapes such as a circle, an ellipse, a triangle or a profile. Similarly, the cross section of the boss 58 can have a variety of shapes, such as an ellipse, a triangle, a polygon, and the like.

The fastener 50 is used to mount the circular saw blade 38 on the output shaft 40, and the fastener 50 passes through the central hole 56 of the circular saw blade 38, thereby connecting the circular saw blade 38 to the mounting portion 52 of the output shaft 40.

In order to quickly install or disassemble the circular saw blade 38, the small circular saw 30 is provided with a quick clamping device that can quickly mount or remove the fastener 50.

In the present embodiment, the fastener 50 includes a pressure plate 64 that mates with the circular saw blade 38 and a stem portion 66 that extends into the receiving aperture 54. The bottom surface of the pressure plate 64 may be substantially tapered. A knob 65 is provided on the bottom surface of the pressure plate for easy pressing by the operator. The stem portion 66 is generally cylindrical. Of course, the cross section of the stem portion 66 can be of a variety of shapes, such as rectangular, elliptical, and the like.

The stem portion 66 includes a fixed end 68 that is coupled to the pressure plate 64 and an oppositely disposed free end 70. The end of the free end 70 is a tapered end.

The rod portion 66 is provided with a step 72 at a position close to the free end 70, and the step 72 is formed substantially sag The abutment surface 74 is perpendicular to the axis X of the output shaft 40. In this embodiment, the outer contour of the abutting surface 74 is circular. Of course, those skilled in the art can easily understand that the outer contour of the abutting surface 74 can be many other shapes, such as multi-joint, elliptical, triangular, etc. Wait. The specific function of the tapered end 70 and the abutting surface 74 will be described in detail later.

Referring to Figure 3, the quick-clamping device includes a resilient member 78 that is movable between a locked position and a released position, an elastic member 78 for causing the locking member 76 to always face the locked position, and optionally engages with the locking member 76. Stop 80.

A mount 81 is attached to the output shaft 40. In the present embodiment, the mount 81 includes first and second split seats 82 and 84, wherein the second split seat 84 is fixedly coupled to the output shaft 40. In the present embodiment, the second split seat 84 is provided with a threaded hole, and the output shaft 40 is externally threaded at the other end away from the mounting portion 52. Thus, the output shaft 40 is coupled to the second split seat 84 by a threaded engagement. together. Of course, the output shaft 40 and the second split seat 84 can also be secured together by screws, rivets, welding, etc., other mounting means well known to those skilled in the art.

The outer side of the mount 81 is provided with a mounting sleeve 86 having an internal thread, and the second split seat 84 is provided with an external thread (not shown). The internal thread of the mounting sleeve 86 cooperates with the external thread of the second split seat 84 to securely connect the first and second split seats 82 and 84 together. Of course, the external thread can also be placed on the first split seat 82. It will be appreciated that the mount 81 can also be a single unitary body; or form a unitary unit with the output shaft 40; or be secured to the output shaft 40 by bolts, screws, rivets, and the like, as is well known to those skilled in the art. .

A guide groove (not labeled) that cooperates with the locking member 76 is provided in the mounting seat 81. The locking member 76 moves in the guide groove to effect a transition between the locked position and the released position.

The first split seat 82 is provided with a first guiding surface 88 that cooperates with the locking member 76. Here, the first guiding surface 88 is inclined with respect to the axis X of the output shaft 40.

As shown in Fig. 4, the second split seat 84 is provided with a second guiding surface 90 which cooperates with the locking member 76. Similarly, the second guiding surface 90 is inclined with respect to the axis X of the output shaft.

When the first and second split seats 82 and 84 are fixedly coupled together, a guiding groove is formed between the first guiding surface 88 and the second guiding surface 90 to cooperate with the locking member 76. Thus, the guide groove is inclined with respect to the axis X of the output shaft.

A limiting groove 92 for accommodating the stopper 80 is disposed in the mounting seat 81. Preferably, the extending direction of the limiting groove 92 is parallel to the axis X of the output shaft. Of course, it will be easily understood by those skilled in the art, The direction in which the bit groove 92 extends may also be inclined with respect to the axis X of the output shaft 40.

The locking member 76 is machined from a rigid material that is mounted in the mount 81 and is located in the space formed by the first and second split seats 82 and 84. The locking member 76 includes a generally U-shaped body 94 having a through hole 96 through which the abutting surface 74 can pass and a limiting hole 98 through which the abutting surface 74 cannot pass. The through hole 96 and the limiting hole 98 are respectively located at both ends of the main body 94 and communicate with each other. The through hole 96 may match the outer contour of the abutment surface 74 or may not match the outer contour of the abutment surface 74, and may only be slightly larger than the outer contour of the abutment surface 74. In the present embodiment, the through holes 96 are substantially square. The limiting hole 98 communicating with the through hole 96 is rectangular and has a width slightly smaller than the side length of the through hole 96.

A locking surface 100 abutting against the abutting surface 74 is formed on the surface of the main body 94. A through hole 96 is opened on the locking surface 100.

Referring to FIG. 5, when the locking member 76 is in the release position, the through hole 96 is aligned with the receiving hole 54 (not shown) on the output shaft 40, so that the abutting surface 74 on the fastener 50 can pass through the through hole 96 at the same time. And the receiving hole 54; referring to FIG. 6, when the locking member 76 is in the locking position, the radially outward movement of the locking member 76 causes the through hole 96 to be displaced from the receiving hole 54 on the output shaft 40, and the limiting hole 98 is The receiving holes 54 are at least partially aligned. Because the limiting holes 98 are narrow, they cannot be passed through the abutting surface 74 of the fastener 50, and under the action of the elastic member 78, the locking surface 100 on the locking member 76 is The abutment surface 74 mates such that the locking member 76 locks the fastener 50 to the output shaft 40. The stem portion 66 includes a stop portion 102 coupled to the step 72, and the stop portion 102 can pass through the stop hole 98.

Two projections 104 extending symmetrically outward from the end of one end of the through hole 96 are provided from the main body 94. The projection 104 includes a limiting surface 106 disposed perpendicular to the abutment surface 74. The limiting surface 106 and the abutment surface 108 on the mounting seat 81 form a space for receiving the elastic member 78. That is, one end of the resilient member 78 abuts against the limiting surface 106 and the other end abuts against the abutment surface 108.

Referring again to Fig. 4, the locking member 76 is provided with a guiding portion 110 adapted to the guiding groove. Of course, the guide groove can also be disposed on the locking member 76, and the guiding portion 110 is disposed on the mounting seat 81.

The guiding portions 110 are disposed on both sides of the through hole 98, and the extending direction of the guiding portion 100 is inclined with respect to the locking surface 100. Therefore, when the locking member 76 moves, the upper and lower surfaces of the guiding portion 100 are respectively engaged with the first and second guiding surfaces 88 and 90, so that the guiding portion 100 can be opposite to the guiding groove. The axis X of the output shaft is tilted. Of course, it will be understood by those skilled in the art that the direction of movement of the locking member 76 can also be perpendicular to the axis X of the output shaft 40.

The stopper 80 is machined from a rigid material that is movably received in the limit groove 92 such that the stopper 80 is movably mounted on the output shaft 40 and movable in the axial direction of the output shaft 40. . Of course, as understood by those skilled in the art, the direction of movement of the stop 80 can be inclined or perpendicular with respect to the axis X of the output shaft 40.

The stop member 80 is selectively engageable with the locking member 76. One of the stopper 80 and the locking member 76 is provided with a fitting groove, and the other of the stopper 80 and the locking member 76 is provided with a fitting portion that cooperates with the fitting portion.

In the present embodiment, the engaging portion 112 is disposed on the stopper 80, and the fitting groove 114 is provided on the locking member 76. The mating groove 114 extends in the axial direction of the output shaft 40.

The stopper 80 includes a body 116, and two fitting portions 112 and two supporting portions 118 extend from upper and lower surfaces of the body 116, respectively. The body 116 is generally in the form of a sheet and is provided with a groove 120 that cooperates with the fastener 50, wherein the groove 120 may have a shape such as a semicircle or an arc. When installed, the semi-circular or curved groove 120 faces the through hole 96 in the locking member 76. Thus, when the tapered end 70 mates with the recess 120, the fastener 50 pushes the stopper 80 to move more stably.

The two fitting portions 112 extend downward from the lower surface of the body 116 in the axial direction and are disposed symmetrically at the center. When the engaging portion 112 is received in the engaging groove 114, the stopper 80 prevents the locking member 76 from moving, and the locking member 76 is in the releasing position; when the engaging portion 112 is disengaged and cooperates with the engaging groove 114, the stopper 80 cannot prevent the locking The member 76 moves and the locking member 76 moves to the locked position by the elastic member 78. Here, the elastic member 78 may be a compression spring, a torsion spring or the like.

The two support portions 118 extend axially upward from the upper surface of the body 116 and are also disposed centrally symmetrically. The support portion 118 is provided with a U-shaped groove 122 for partially accommodating the spring 124. The spring 124 is used to urge the stop member 80 into engagement with the locking member 76.

In summary, in the release position, the stop member 80 cooperates with the locking member 76 to remove the fastener 50 from the output shaft 40, so that the circular saw blade 38 can be quickly disassembled; during the release position to the locking position The fastener 50 pushes the stopper 80 to urge the stopper 80 to disengage from the locking member 76, and the locking member 76 moves to the locking position by the elastic member 78; in the locking position, the rod portion 66 is clamped to the output shaft 40, and the circular saw blade 38 is clamped between the mounting portion 52 and the pressure plate 64, so that the circular saw blade 38 can be quickly mounted. This makes it possible to quickly replace the circular saw blade 38 without the need for an external aid.

Referring again to Figure 3, to facilitate the transition of the locking member 76 from the locked position to the released position, the small electric circular saw also includes a drive member 126 that causes the locking member 76 to move. By operating the drive member 126, the locking member 76 can be moved from the locked position to the released position, thereby allowing the fastener 50 to be removed from the output shaft 40. The driving member 126 is movably disposed on the mount 81 to drive the locking member 76 to move in a direction inclined with respect to the axis X of the output shaft 40.

The driving member 126 includes an operating portion 128 operable by an operator, an engaging portion 130 and a guiding portion 132 connected to the operating portion 128. The guide portion 132 cooperates with the guide groove 134 on the mounting seat 81 to move the driving member 126 between the driving position and the initial position, wherein the guiding groove 134 extends in a direction parallel to the axial direction of the output shaft 40. As such, the drive member 126 is operatively movable in the axial direction of the output shaft 40. Of course, the driving member 126 can also be moved in a direction inclined with respect to the axis X of the output shaft 40 or by rotation or the like on the mounting seat 81.

The engaging portion 130 includes a first engaging surface 136 which is disposed obliquely in the axial direction. When the driving member 126 is movable, the locking member 76 is driven to move by the first engaging surface 136.

The locking member 76 is provided with a second mating surface 138 (shown in Figure 4) that mates with the first mating surface 136, the second mating surface 138 being disposed obliquely with respect to the axis X of the output shaft 40.

The driving portion 126 is pressed such that the first engaging surface 136 engages with the second engaging surface 138, thereby driving the locking member 76 to move from the locked position to the released position.

Referring to Fig. 7, in the present embodiment, a spring 124 is disposed between the stopper 80 and the driving member 126. Therefore, the spring force of the spring 124 causes the drive member 126 to always be in the initial position; at the same time, the stop member 80 is urged to always be in a position to engage the lock member 76. Of course, the small electric circular saw 30 can also be provided with two springs which respectively urge the drive member 126 to the initial position and urge the stop member 80 to always engage the locking member 80.

The locking and releasing process of the circular saw blade 38 of the present embodiment will be described below with reference to Figs. 8 and 9. The driving member 126 can drive the locking member 76 to be switched from the locking position to the releasing position. In the locking position, the fastener 50 is clamped by the locking member 76, thereby stably fixing the circular saw blade 38 to the output shaft 40. In the released position, the locking member 50 releases the fastener 50, allowing the fastener 50 to be removed from the output shaft 40, thereby removing the circular saw blade 38. Therefore, the small circular saw can quickly replace the circular saw blade 38 without the need for an external auxiliary tool.

As shown in Figure 8, the locking member 76 is now in the released position. In this position, the stop member 80 cooperates with the locking member 76 under the action of the spring 124. That is, under the action of the spring 124, the engaging portion 112 on the stopper 80 is engaged in the fitting groove 114 on the locking member 76. At this time, the through hole 96 in the locking member 76 is substantially aligned with the receiving hole 54 in the output shaft 40. The locking surface 100 on the locking member 76 is disengaged from the fastener 50. At this point, the locking member 76 is in the release fastener 50, which in turn removes the fastener 50 from the locking member 76 so that the circular saw blade 38 can be removed. It should be noted that the above-described release position is to move the drive member 126 by an external force to cause the lock member 76 to move to the release position. In the release position, although the external force is removed, the driving member 126 is returned to the initial position due to the action of the spring 124; the engaging portion 112 on the stopper 80 is engaged in the engaging groove 114 on the locking member 76, thereby The locking member 76 is held in the released position.

Prior to mounting the fastener 50 into the output shaft 40, the circular saw blade 38 is first mounted between the mounting portion 52 of the output shaft 40 and the pressure plate 64. The circular saw blade 38 can be first mounted on the mounting portion 52 of the output shaft 40, and then the fastener 50 is passed through the central hole 56 of the circular saw blade 38 and into the receiving hole 54 of the output shaft 40. The fastener 50 passes through the central opening 56 of the circular saw blade 38 and extends into the receiving aperture 54 of the output shaft 40.

When the lock is required, the user presses the knob 65 on the fastener 50 (see Fig. 3), and the free end 70 of the fastener 50 cooperates with the recess 120 of the stopper 80 to urge the stopper 80 to overcome. The spring force of the spring 124 is axially displaced a certain distance until the mating portion 112 on the stop member 80 disengages from the mating groove 114 on the locking member 76. The stopper 80 moves in the axial direction of the output shaft 40 during the movement of the stopper 80.

As shown in FIG. 9, when the engaging portion 112 on the stopper 80 is disengaged from the engaging groove 114 on the locking member 76, the locking member 76 is moved by the elastic member 78 and clamps the rod portion 66. .

It should be noted that during the locking process, the locking member 76 is inclinedly moved relative to the axis X of the output shaft 40 by the elastic member 78; under the action of the elastic member 78, the movement of the locking member 76 causes the through hole 96 to The receiving holes 54 of the output shaft 40 are staggered, so that the limiting portion 102 on the fastener 50 is located in the limiting hole 98. With the further action of the resilient member 78, the locking surface 100 on the locking member 76 engages the abutment surface 74 of the fastener 50, and the fastener 50 is clamped by the locking member 76 to secure the circular saw blade 38 thereto. Between the mounting portion 52 and the pressure plate 64.

It is noted that in the above-described locked position, the locking surface 100 is disposed substantially perpendicular to the axis X of the output shaft 40.

It is noted that in the locked position described above, the stop member 80 compresses the spring 124. The stopper 80 is held at a position that is not engaged with the lock member 76 by the step surface opposite to the abutment surface 74.

It should be noted that in the present embodiment, the moving direction of the locking member 76 is inclined relative to the direction in which the axis X of the output shaft 40 extends, and is not vertically disposed. This is because the small electric circular saw 30 can be installed with different brands and different types of circular saw blades, and the thickness of such circular saw blades is bound to be inconsistent. Therefore, the tilting arrangement eliminates the axial gap due to the non-uniform thickness of the circular saw blade. Therefore, as can be understood by those skilled in the art, it is also possible to eliminate the cooperation of the inclined surface and the abutting surface of the fastener. In addition to the axial clearance due to the uneven thickness of the circular saw blade. Of course, if the moving direction of the locking member 76 is perpendicular to the extending direction of the axis X of the output shaft 40, the locking member 76 can also fix a circular saw blade of a certain thickness.

In the above, the clamping process of the small electric circular saw 30 of the present embodiment has been described in detail, and the release process is reversed from the clamping process. When the circular saw blade 38 needs to be detached from the output shaft 40, the drive member 126 is moved in the axial direction parallel to the output shaft 40 by simply pressing the driving portion 128 of the driving member 126 and compressing the spring 124. During the movement of the driving member 126, the first engaging surface 136 engages with the second engaging surface 138 of the locking member 76, thereby driving the locking member 76 to move. When the locking member 76 is moved toward the mounting seat 81, the locking surface 100 is disengaged from the abutting surface 74, and the through hole 96 is moved to a position substantially aligned with the receiving hole 54, thereby releasing the fastener 50. The stopper 80 is axially moved downward by the elastic force of the spring 124. Since the groove 120 of the stopper 80 is engaged with the free end 70, the fastener 50 is driven, and finally the fastener 50 is driven from the output shaft. A certain distance is pushed in, so that the fastener 50 can be easily taken out from the output shaft; at the same time, the stopper 80 is axially moved downward until the engaging portion 112 cooperates with the engaging groove 114, and the stopper 80 blocks the locking member. 76 moves, the locking member 76 is in the release position.

It should be noted here that, as shown in FIG. 9, in the present embodiment, the receiving hole 54 is provided with a threaded hole 139 at an end close to the circular saw blade 38. If the fastener is replaced with a threaded fastening bolt or screw. When the circular saw blade 38 is mounted, it is only necessary to pass the fastener through the central hole 56 in the circular saw blade 38 and threadedly engage the threaded hole 139, and the circular saw blade 38 can also be fixed to the output shaft 40.

Referring to Figure 10, a protective cover 140 is provided on the front portion 42 of the housing. The shield 140 includes a generally circular aperture 142. The aperture 142 can be closed or semi-closed for receiving the drive member 126. Thereby, the user is prevented from erroneously operating the driving member 126; or the driving member 126 is actuated by placing the small electric circular saw 30 on the table.

The present invention is not limited to the foregoing embodiments, and other changes may be made by those skilled in the art in light of the spirit of the present invention. However, as long as the functions implemented are the same or similar to the present invention, they should be covered by the scope of the present invention. .

Claims

Claim

What is claimed is: 1. A power tool, characterized in that: the power tool comprises:

An output shaft for mounting and driving the working head, comprising a longitudinally extending receiving hole; a fastener for fixing the working head to the output shaft, comprising a rod extending into the receiving hole;

a locking member movable between the locked position and the released position for locking and releasing the fastener; and an elastic member for causing the locking member to always face the locked position;

a stopper, optionally mate with the locking member;

In the release position, the stop cooperates with the locking member to remove the fastener from the output shaft; the fastener pushes the stop during the release position to the locking position Actuating member, causing the stopper to disengage from the locking member, the locking member is moved to the locking position by the elastic member; in the locking position, the locking member will The fastener is locked to the output shaft.

2. The power tool according to claim 1, wherein: the stopper is selectively engageable with the locking member along an axial direction of the output shaft.

The power tool according to claim 1 or 2, wherein: one of the stopper and the locking member is provided with a fitting groove, and the stopper and the locking member The other of the two is provided with a fitting portion, and the fitting groove cooperates with the fitting portion.

The power tool according to claim 1 or 2, wherein: the stopper is provided with a groove that cooperates with the fastener, and the groove is semicircular or curved.

5. The power tool according to claim 1, wherein: the lever portion includes an abutting surface perpendicular to an axis of the output shaft, and the locking member includes a passage surface through which the abutting surface can pass a through hole and a locking surface that cooperates with the abutting surface, wherein the locking surface is provided with a limiting hole through which the abutting surface cannot pass, wherein the through hole and the limiting hole are in communication.

The power tool according to claim 5, wherein: the output shaft is connected with a mounting seat, and one of the mounting seat and the locking member is provided with respect to the output shaft An axially inclined guiding groove is provided with a guiding portion on the other of the mounting seat and the locking member, and the guiding groove cooperates with the guiding portion.

7. The power tool according to claim 6, wherein: the mounting seat comprises first and second split seats, and the guiding groove is formed by the first and second split seats.

8. The power tool according to claim 1, wherein: the power tool further comprises a driving member for causing movement of the locking member, the driving member comprising a first engaging surface that engages with the locking member When the driving member is active, the locking member is driven to move by the first engaging surface.

9. The power tool according to claim 8, wherein: the locking member is provided with a second engaging surface matching the first engaging surface, and the second engaging surface is opposite to the output shaft The axis is tilted.

A power tool according to claim 8, wherein: a spring is provided between the stopper and the driving member.

A power tool according to claim 8, wherein: said driving member is disposed on said output shaft so as to be movable in the axial direction of said output shaft.

The power tool according to claim 1, wherein the stem portion is provided with a tapered end that engages with the stopper.

The power tool according to claim 1, wherein the receiving hole is provided with a threaded hole at an end close to the saw blade.