JPH0680573U - Hammer tool - Google Patents

Abstract

(57) [Abstract] [Object] The present invention relates to a striking tool for transmitting the rotational motion of a drive shaft by using a winding transmission device, and an object of the present invention is to reduce a gear by eliminating a gear by using the winding transmission device. Noise and weight are reduced, and the transmission torque is arbitrarily regulated based on the relationship between belt slip and tension to serve as a slip torque mechanism to reduce costs. [Structure] The rotary motion of the drive shaft 2 of the impact tool is transmitted to the intermediate shaft 4 via the V-belt 3 and further to the cylinder 6 and the tip tool 7 via the flat belt 5. Also, flat belt 5
The slip torque of the flat belt 5 is regulated by adjusting the tension of the, and the transmission torque to the tip tool 7 is regulated.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an impact tool such as an electric hammer drill having a motion conversion mechanism section, an impact mechanism section, and a rotation transmission mechanism section.

[0002]

[Prior art]

 In the conventional technique, as shown in FIG. 3, the rotational movement of the drive shaft 2 is transmitted to the intermediate shaft 4 via the first gear 19. Further, the intermediate shaft 4 has a structure in which the rotation is always transmitted to the tip tool 7 via the second gear 20 provided on the cylinder 6.

Further, the transmission torque to the tip tool 7 is regulated by disposing concave and convex claws 21 on the second gear 20 and the cylinder 6 and engaging them, and further applying a certain load by the spring 22. It was structured.

[0004]

[Problems to be solved by the device]

 In the conventional device, since the transmission of the rotary motion uses the steel gear, there is a problem that gear noise is generated, cost is increased, and the gear becomes heavy.

Further, the torque transmitted to the tip tool is regulated by applying a load using a spring, a washer, and a shaft C snapper while the second gear and the concave and convex claws provided on the cylinder are engaged with each other. The number of points is increased, the cost is increased, the weight is increased, and the transmission torque regulating device is provided on the cylinder, so that the total length is increased. Further, since the load is applied by the spring and the shaft C is fixed by the snap ring, there is a problem that the transmission torque cannot be arbitrarily adjusted.

An object of the present invention is to eliminate the above problems.

[0007]

Means for Solving the Problems The above-mentioned object is achieved by making a drive shaft and an intermediate shaft, and / or an engagement of an intermediate shaft and a cylinder into a winding transmission device. Further, the adjustment of the transmission torque is achieved by providing a device that can adjust the tension of the winding intermediary node from the outside of the main frame.

[0008]

[Action]

 The striking tool configured as described above operates to transmit the rotational movement of the drive shaft by the winding transmission device. Further, the tension adjusting device for the winding medium joint operates so as to regulate the transmission torque to the tip tool by arbitrarily adjusting the tension of the winding medium joint.

[0009]

【Example】

 The present invention will be described below with reference to the embodiment of FIGS. 1 and 2 in which the rotational movement of the drive shaft 2 is transmitted to the intermediate shaft 4 via the V-belt 3. Further, the intermediate shaft 4 rotates the cylinder 6 via the flat belt 5 and constantly transmits the rotation to the tip tool 7. On the intermediate shaft 4, there is provided a swinging body 8 and a clutch 9 which are rotatably engaged with each other. The splines are engaged and arranged. The cylinder 6 is constantly urged forward by a spring 17 via a thrust plate 10 and a thrust bearing 11, and is arranged so as to be movable in the axial direction. The thrust plate 10 comes into contact with the groove 9a of the clutch 9 and the clutch 9 simultaneously moves forward when moving forward. A flange portion 6a, which is concentric with the cylinder 6, is formed on the cylinder 6 so as to overlap with the side surface of the clutch 9. When the clutch 9 is retracted, the concavities and convexities at the ends of the rocking body 8 and the clutch 9 are engaged, and the intermediate shaft 4 and the rocking body 8 are engaged.

In this structure, when the tip tool 7 is pressed against the work material as shown in FIG. 1, the cylinder 6 moves backward against the spring 17. At the same time, it abuts on the cylinder 6 and retracts the clutch 9. As a result, the clutch 9 engages with the oscillating body 8, so that the driving force of the intermediate shaft 4 is transmitted to the oscillating body 8 and the piston 13 reciprocates via the piston pin 12. Further, the impact element 15 follows by the air spring of the air chamber 14 provided in the piston 13, and impacts the tip tool 7 via the intermediate element 16. The hitting section, the converting section that converts the rotation into the reciprocating motion, and the rotation transmitting section are collectively referred to as the mechanism section chamber 18a. As a result, when transmitting the rotational movement of the drive shaft 2 to the intermediate shaft 4, and further when transmitting it from the intermediate shaft 4 to the cylinder 6, gear noise does not occur, and thus work can be performed with low noise.

Further, the torque transmitted to the tip tool 7 is set by the tension of the flat belt 5 by utilizing the feature that the flat belt 5 slips when the load increases. As a result, parts for controlling the transmission torque can be eliminated, the cylinder 6 can be shortened, and the product can be made smaller and lighter, and the cost can be significantly reduced.

[0012]

[Effect of device]

 According to the present invention, since the winding transmission device is used for transmitting the rotary motion of the rotary drive source, the rotary motion can be transmitted without disposing a gear on the driving shaft or the driven shaft. In addition, since belts, ropes, etc. are used for the winding medial parts of the winding transmission device, low noise operation and weight reduction can be achieved. Furthermore, when the transmission method is friction, slipping occurs when the load increases, so that it can function as a transmission torque regulating device for the tip tool, and the transmission torque regulating device can be removed, and parts can be removed. The cost can be reduced and the size and weight can be reduced. Furthermore, the torque transmitted to the tool bit can be arbitrarily regulated by adjusting the tension of the winding medium node of the winding transmission device.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of an essential part showing an embodiment of a tool of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a vertical cross-sectional side view of essential parts showing an embodiment of a hitting tool according to a conventional technique.

[Explanation of symbols]

2 is a drive shaft, 3 is a V belt, 4 is an intermediate shaft, 5 is a flat belt, 6 is a cylinder, and 7 is a tip tool.

Claims (4)

[Scope of utility model registration request] 1. A rotary drive source, a conversion mechanism section for converting the rotational movement of the rotary drive source into a reciprocating movement, a striking mechanism section connected to the conversion mechanism section, and a rotation transmission for transmitting the rotation to the tip tool. A striking tool having a mechanism section, wherein a winding transmission device is provided on the rotation drive shaft and the rotation transmitting mechanism section. 2. The impact tool according to claim 1, wherein a belt, a rope, a V-belt, a chain or the like is used as a winding medium node of the winding transmission device. 3. The impact tool according to claim 1, wherein the transmission method of the winding transmission device is transmission by friction and meshing. 4. The striking tool according to claim 1, wherein the transmission torque to the tip tool can be regulated by adjusting the tension of the winding medium node of the winding transmission device.