CN101683733A - Clutch device of electric tool - Google Patents

Abstract

The invention relates to a clutch device of an electric tool, which is provided with an input gear, a transmission shaft, a first clutch, a second clutch, an output shaft and a spring. The connection between the clutch device and the motor of the electric tool and the connection between the clutches are independent and irrelevant, so that the manufacturing cost can be reduced and greater material selection flexibility can be achieved.

Description

Clutch device for electric tools

technical field

The invention relates to an electric tool, in particular to a clutch device of an electric tool

Background technique

After the general electric tool is started, the motor will drive the output shaft to rotate, and then drive the tool parts connected to the output shaft, such as a screwdriver bit, to rotate. When performing screw locking operations, the continuously rotating bit of the screwdriver will be difficult to combine with the screw, and it is easy to damage the screw. Therefore, whenever a screw is locked, the power tool must be stopped first, and then restarted after the screwdriver head is combined with the screw. Of course, this is quite an inconvenient operation in the operation of continuously locking screws. To solve the aforementioned problems, US Patent No. 5,138,916 provides an electric power tool in which a clutch device is disposed. The electric tool is provided with a first clutch and a second clutch, wherein the periphery of the first clutch is provided with teeth for meshing with the gear of the output shaft of the motor, and the front side of the first clutch is provided with clutch teeth. The rear side of the second clutch is also provided with a clutch tooth. A spring is arranged between the first clutch and the second clutch. Under normal conditions, the clutch teeth of the first clutch are separated from the clutch teeth of the second clutch. The second clutch is connected to an output shaft to which a tool, such as a screwdriver bit, can be connected. When the electric tool is started, the motor drives the first clutch to rotate, but the second clutch, the output shaft and the screwdriver head do not rotate. When an external pressure is applied to the screwdriver bit, it will cause the screwdriver bit, the output shaft and the second clutch to retreat, and then the clutch teeth of the first clutch will mesh with the clutch teeth of the second clutch. At this time, the power of the motor will be Through the first clutch, the second clutch and the output shaft, it is transmitted to the screwdriver head to make it rotate. When the external pressure disappears, the spring will push away the second clutch to cut off the transmission relationship between the motor and the screwdriver bit.

We found that the clutch device provided by the aforementioned invention has the following problems: In order to consider the problems of material wear and strength, the first clutch and the second clutch must be made of high-strength materials, and both must be made of the same material . To cooperate with the first clutch, the output shaft of the motor must also be made of the same material as the first clutch. This would substantially increase the cost of manufacture. In addition, the arrangement of the spring will also increase the difficulty of assembly.

Contents of the invention

The main purpose of the present invention is to provide a clutch device of an electric tool, which has greater flexibility in material selection.

Another object of the present invention is to provide a clutch device of an electric tool, which has lower manufacturing cost and simpler assembly method.

In order to achieve the object of the above-disclosed invention, the clutch device of the electric tool of the present invention mainly includes a motor with an output shaft and a gear on the output shaft; a clutch device with an input that meshes with the gear of the motor gears; a transmission shaft, connected to the input gear; a first clutch, connected to the transmission shaft, with clutch teeth on one side; and a second clutch, with clutch teeth corresponding to the clutch teeth of the first clutch; An output shaft, whose outer end can be connected with a tool piece, and whose inner end is connected with the second clutch; wherein the inner end of the output shaft has a hole; and a spring is arranged in the hole of the output shaft.

In order to describe the structure and characteristics of the present invention in detail, the following preferred embodiments are given and illustrated in conjunction with the drawings as follows:

Description of drawings

Fig. 1 is a sectional view of a preferred embodiment of the present invention;

Figure 2 is a partial sectional view of a preferred embodiment of the present invention, showing that the first clutch and the second clutch are separated;

Fig. 3 is a perspective view of some components of a preferred embodiment of the present invention, showing that the first clutch and the second clutch are separated;

Figure 4 is a partial cross-sectional view of a preferred embodiment of the present invention showing the engagement of the first clutch and the second clutch; and

Fig. 5 is a perspective view of some components of a preferred embodiment of the present invention, showing that the first clutch and the second clutch are engaged.

Description of main component symbols

power tool 1

Housing 10 Trigger 11

Motor 20 Output shaft 21

Gear 211 clutch device 30

Input gear 31 Drive shaft 32

Polygonal hole 321 The first clutch 33

Polygonal column part 331 Clutch teeth 332

Perforation 333 Second clutch 34

Polygonal column part 341 Clutch teeth 342

Perforation 343 Ring shoulder 344

Support shaft 35 board 351

Spring 36 output shaft 40

Polygonal hole 41 Polygonal hole 42

Tool pieces 50

Detailed ways

Please refer to FIG. 1 , an electric tool 1 provided by a preferred embodiment of the present invention includes: a housing 10 in which a motor 20 , a clutch device 30 and an output shaft 40 are installed. The casing 10 is provided with a trigger 11 for controlling a switch to connect or cut off the power of the motor 20 . The power of the motor 20 is transmitted to the output shaft 40 through the clutch device 30 . The outer end of the output shaft 40 can be connected with a tool part 50 (shown as a subhead in the figure) for related operations.

Please refer to FIG. 2 , the clutch device 30 includes an input gear 31 , a transmission shaft 32 , a first clutch 33 , a second clutch 34 , a support shaft 35 and a spring 36 .

One end of the transmission shaft 32 is pivotally mounted on the casing 10 such that it can freely rotate along its axial direction. The input gear 31 is fixed on the transmission shaft 32 to mesh with the gear 211 on the output shaft 21 of the motor 20 . A front end of the transmission shaft 32 has a polygonal hole 321 .

The rear side of the first clutch 33 has a polygonal post 331 , which can be inserted into the polygonal hole 321 of the transmission shaft 32 , so that the first clutch 33 and the transmission shaft 32 are combined together. The rear side of the first clutch 33 has an annular clutch tooth 332 , and the center of the clutch tooth 332 has a through hole 333 .

The second clutch 34 is symmetrical to the first clutch 33 , and has a ring-shaped clutch tooth 342 at the rear, a through hole 343 at the center of the clutch tooth 342 , and a polygonal post 341 at the front. The second clutch 34 further has an annular shoulder 344 surrounding the inner end of the polygonal post 341 .

One end of the supporting shaft 35 is inserted into the through hole 333 of the first clutch 33 , the other end passes through the through hole 343 of the second clutch 34 , and a plate is arranged on the end passing through the through hole 343 of the second clutch 34 351.

The outer end of the output shaft 40 protrudes from the housing 10 and has a polygonal hole 41 for inserting a tool 50 (shown as a bit in FIG. 3 ). The inner end of the output shaft 40 has a polygonal hole 42 for inserting the polygonal column 341 of the second clutch 34 to combine together, and the inner end of the output shaft 40 abuts against the shoulder of the second clutch 34 On face 344. The spring 36 is disposed in the polygonal hole 42 of the output shaft 40 , one end leans against the plate 351 of the support shaft 35 , and the other end leans against the inner end of the polygonal hole 42 of the output shaft 40 .

In a normal state, please refer to FIG. 2 and FIG. 3, the spring 36 will push the output shaft 40 and the plate 351 of the support shaft 35 outward, so that the clutch teeth 342 of the second clutch 34 and the second clutch 34 A clutch tooth 332 of a clutch 33 is disengaged. At this moment, although the motor 20 drives the first clutch 33 to rotate via the input gear 31 and the transmission shaft 32 , the output shaft 40 still does not rotate.

4 and 5, when the tool part 50 receives a certain pressure, it will push the output shaft 40 and the second clutch 34 back, so that the clutch teeth 342 of the second clutch 34 and the first clutch 33 At this time, the power of the motor 20 can be transmitted to the output shaft 40 to drive the tool part 50 to rotate to perform predetermined operations. And when the pressure disappears, the spring 36 will push the transmission shaft 40 outward, so that the clutch teeth 342 of the second clutch 34 are separated from the clutch teeth 332 of the first clutch 33 to cut off the power.

According to the structure of the present invention, the connection between the clutch device 30 and the motor 20 (the gear 211 of the input gear 31 and the motor output shaft 21) and the connection of the clutch (the clutch teeth 332 of the first clutch 33 and the clutch teeth 342 of the second clutch 34 ) are independent and uncorrelated. Therefore, although the first clutch 33 and the second clutch 34 still need to be made of high-strength materials, the input gear 31 and the gear 211 of the motor output shaft 21 can be made of low-strength materials (for example: plastic), so that the manufacturing cost. In addition, the spring 36 is installed in the hole 42 of the output shaft 40, which can achieve a relatively simple assembly procedure.

Claims (9)

1, a kind of arrangement of clutch of electric tool is characterized in that including:

One motor has an output shaft, and has a gear on this output shaft;

One arrangement of clutch has an input gear, with the gears engaged of this motor; One power transmission shaft is connected in this input gear, is rotated by this input gear driven; One first clutch is connected in this power transmission shaft, and the one side has the clutch tooth; And a second clutch, have the clutch tooth, corresponding with the clutch tooth of this first clutch;

One output shaft, its outer end connects a tool piece, and the inner then connects this second clutch; Wherein the inner of this output shaft has a hole, and this output shaft can move along direction approaching and away from this first clutch, when this output shaft away from this first clutch, the clutch tooth of this first clutch separates with the clutch tooth of this first clutch, and this output shaft is near this first clutch, and the clutch tooth of this first clutch and the clutch tooth of this first clutch mesh; And

One spring is arranged in the hole of this output shaft, and this output shaft is pushed against towards the direction away from this first clutch.

2, according to the arrangement of clutch of the described electric tool of claim 1, it is characterized in that, also has a support bar, one end inserts in the perforation of this first clutch, the other end then passes the perforation of this second clutch, and stretch in the hole of this output shaft, make an end of this spring be resisted against on this support bar.

According to the arrangement of clutch of the described electric tool of claim 2, it is characterized in that 3, the end of this support bar in stretching into the hole of this output shaft is provided with a plank, make an end of this spring be resisted against on this plank.

According to the arrangement of clutch of the described electric tool of claim 1, it is characterized in that 4, this second clutch has a shoulder face, the inner of this output shaft is resisted against on this shoulder face.

According to the arrangement of clutch of the described electric tool of claim 1, it is characterized in that 5, an end of this power transmission shaft has a hole, this first clutch has a post portion, inserts in the hole of this power transmission shaft, with in conjunction with this power transmission shaft and this first clutch.

6, according to the arrangement of clutch of the described electric tool of claim 5, it is characterized in that, the Kong Weiyi polygonal holes of this power transmission shaft, the post portion of this first clutch is a polygonal post portion.

According to the arrangement of clutch of the described electric tool of claim 1, it is characterized in that 7, this second clutch has a post portion, insert in the hole of this output shaft, with in conjunction with this power transmission shaft and this second clutch.

8, according to the arrangement of clutch of the described electric tool of claim 7, it is characterized in that, the Kong Weiyi polygonal holes of this output shaft, the post portion of this second clutch is a polygonal post portion.

According to the arrangement of clutch of the described electric tool of claim 1, it is characterized in that 9, the gear of this input gear and this motor is made with the lower material of intensity.

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