JPH05192B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an impact tool having a cutting edge with circumferential directionality and having a structure in which the directionality of the bit can be easily changed.

[Prior Art] A striking tool that chisels or forms grooves in concrete by striking a chisel-shaped bit has a flat tip, so it has directionality in the circumferential direction. The work was carried out by relating the characteristics to the parts to be operated such as the handle and frame of the impact tool.

For this reason, the relationship between the bit and the handle is determined assuming a general posture, and since the working posture changes between a flat part such as a floor or wall and a vertical part, it is difficult for the worker to I was operating it by changing the way I held it.

However, the operating parts such as the handle are originally in the safest and easiest condition to work with, and some models allow the installation position of the handle to be changed to accommodate such conditions. .

However, the working posture changes very frequently during the work, and changing the mounting position of the handle each time becomes an impediment to the work and is not practical.

In addition, a large circumferential force is generated at the cutting edge,
If the device is operated with a large amount of force, even if the position of the handle is changed, it is not possible to operate the device uniformly in each circumferential direction, including the relationship with the weight balance of the entire main body.

[Problems to be Solved by the Invention] Under these circumstances, the present invention solves these problems in an impact tool that uses a bit that has directionality in the circumferential direction, and allows the handle etc. to quickly respond to the directionality of the bit. The purpose of the present invention is to provide an impact tool that is easy to operate and can be used safely and reliably.

[Means for Solving the Problems] The present invention provides a groove in the circumferential direction that is open toward the end at the rear end of the bit, and is fitted into this groove to restrain the bit in the rotational direction. The problem is solved by providing a key and biasing the bit toward the end with a spring.

[Operation] When changing the bit's position, pull the bit opposite to the spring, remove the engagement between the groove at the rear end of the bit and the key, rotate it, hold the bit in the desired position, and align the groove of the bit with the key. are fitted to restrict the orientation in the direction of rotation.

In this way, the bit can easily change its posture by pulling against the spring.
It is possible to change the posture of the bit without causing any hindrance to work that requires changing posture.

[Example] The present invention will be described in detail based on an example shown in the drawings. Fig. 1 is a longitudinal cross-sectional view of a main part of an impact tool according to an example of the present invention, and Fig. , is a vertical sectional view of the bit portion thereof, and FIG. 3 is an external view showing the impact tool.

In FIG. 1, the impact tool has a bit 1 at one end.
The bit 1 has a tip 2 formed in a U-shape so as to form a groove in concrete or the like, and is oriented in the circumferential direction.

A spring 4 is provided at one end of the main body side 3 of the impact tool to prevent the bit 1 from falling off.

Furthermore, the end 5 located on the main body side 3 of the bit 1
A plurality of grooves 6 which are open toward the rear end are arranged in the circumferential direction.

In addition, keys 7 formed by balls are fitted into the grooves 6, and the grooves 6 are configured not to rotate via the keys 7, and the rotation of the bit 1 is restrained by the main body side 3 in the rotational direction. It is something that exists.

The bit 1 is provided with a collar 8, and is configured so that the spring 4 comes into contact with the collar 8, so that even if the bit 1 tries to come off from the main body side 3, the collar 8 hits the spring 4 and does not come off. It is configured.

Further, the bit 1 is configured such that the end portion 5 is struck, and the blow is transmitted to the tip 2 of the bit 1, and is used for forming grooves in concrete, etc., and removing sealing material filled in the grooves. configured for use.

The bit 1 is configured so that the collar 8 hits the spring 4 and does not come off easily, but the spring 4
When the bit 1 is strongly pulled in the direction of the tip 2 against the bias of the bit 1, the spring 4 is expanded and the bit 1 is pulled and moved in the direction of the tip.

Then, when the bit 1 is strongly pulled toward the tip, the groove 6 formed in the end 5 of the bit 1 is disengaged from the key 7 fixed to the main body side 3, and is no longer restricted in the rotational direction.

Furthermore, when the tension on the bit 1 is released, the bit 1 is moved between the key 7 and the groove 6 by the bias of the spring 4.
The grooves 6 and the keys 7 move so that they fit into each other, and are restrained in the rotational direction at a position where the grooves 6 and the keys 7 coincide in the rotational direction.

In FIG. 2, the end portion 5 of the bit 1 is provided with a groove 6 at a constant angle in the circumferential direction, and is configured to be fixed at every predetermined angle.

In FIG. 3, the impact tool has a bit 1 at one end.
is attached, one handle 9 is provided at the other end, and the other handle 10 is provided approximately in the center.

With this configuration, the impact tool allows the bit 1 to be placed in any desired position while gripping the handles 9 and 10 so as to be in a position convenient for the work.

That is, when the bit 1 is pulled against the spring 4, rotated to an arbitrary position, and released, the spring 4 inserts the bit 1 into the main body side 3, and the groove 6 and the key 7 are fitted. At this position, the bit 1 is restrained in the rotational direction by the main body side 3.

Therefore, the orientation of the bit 1 in the rotational direction can be obtained independently of the handles 9 and 10.

Further, such a change in the posture of the bit 1 can be done extremely easily by pulling the bit 1 against the spring 4, so that it can be carried out without any trouble to the work.

Various types of bits 1 can be used depending on the purpose, and if a groove 6 into which a key 7 can fit is formed in the end 5, the shape of the tip 2 of the bit 1 can be changed. Without limitation, for example, a flat spatula-shaped bit may be used, and various types of bits whose orientation is limited in the direction of rotation can be used.

[Effects of the Invention] According to the present invention, the bit can be arbitrarily fixed at a specific position in the rotational direction, so the bit can be held against the spring without changing the position of the handle on the main body. Since it can be easily operated by pulling and rotating, it is extremely convenient for work, and has the effect of allowing safe and reliable work.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of the main parts of an impact tool according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of the bit part, and FIG. 3 shows the external appearance of the impact tool. FIG. 1...Bit, 3...Body side, 4...Spring, 6...Groove, 7...Key, 9, 10...Handle.

Claims (1)

[Claims] 1. In an impact tool equipped with a bit having circumferential directionality at the cutting edge, a groove that is open toward the end is provided in the circumferential direction at the rear end of the bit, and the bit is fitted into this groove to rotate the bit. A key is provided to restrict the direction,
An impact tool characterized in that the bit is urged toward the end by a spring.