JPH11156756A - Hammering tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the life of a buffering member by providing a regulating member regulating deformation amount of the buffering member on the upper side of the opposed surface of the buffering member opposed to a cylinder. SOLUTION: When a tip tool 1 is separated from a material to be cut at the time of machining, shaft force generated on the side of the tip tool 1 by colliding an intermediate hammering element 5 with a retainer sleeve 2 is transmitted from the retainer sleeve 2 to a cylinder 3 via a needle pin 4, is further transmitted from the cylinder 3 to a bearing 12 and a plate 16, is finally transmitted to an urethane ring 17 and is absorbed. This urethane ring 17 has a fixed interference in the shaft direction, is held between the plate 16 and a front cover 18 and fixes the bearing 12. Because the plate 16 is formed into an L-shape by integrally forming a part which is abutted on the side surface located on the side of an anti-tip tool 1 of the urethane ring 17 and regulating member 16a which can be abutted on the opposed surface 17a, the compression deformation amount is regulated by the regulating member 16ad, even if large shaft force pulling the tip tool 1 out to the front is generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regulating member capable of regulating the amount of deformation of a cushioning material used for a hammer drill or the like.

[0002]

2. Description of the Related Art FIG. 2 is a longitudinal sectional side view showing a striking tool provided with a buffer member 17 '. The cushioning member 17 ′ has a surface 17 ″ facing the cylinder 3. Both side surfaces of the cushioning member 17 ′ are held by the plate 16 ′ and the front cover 18 ′, and the cushioning member 17 ′ is on the side opposite to the cushioning member 17 ′. Is held by the inner peripheral surface of the cylinder case 11.

[0003]

In the above configuration, since the buffer member does not hold any opposing surface, if the axial force of the intermediate striker is large, the buffer member is deformed to a position where it can be deformed. Has a problem that the cushioning member is deformed and cannot return to the original state. In addition, when the shock absorbing member thermally expands due to the heat generated at the time of impact, the shock absorbing member is deformed toward the cylinder side. Therefore, there is a similar problem as described above in that the shock absorbing member does not return to its original state while being deformed.

[0004] An object of the present invention is to solve the above-mentioned problem and to improve the life of the cushioning member by regulating the amount of deformation of the cushioning member.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an intermediate striker for transmitting an impact force to a tool bit, a cylinder for accommodating the intermediate striker, a bearing for rotatably supporting the cylinder, and a side face of the bearing. A shock-absorbing tool comprising: a shock-absorbing member having one end in contact with the provided plate and the other end in contact with the front cover, wherein the shock-absorbing member has a surface facing the cylinder, and further has a shock-absorbing surface above the opposing surface. This is achieved by providing a regulating member that regulates the amount of deformation of the member.

[0006]

FIG. 1 is a longitudinal sectional side view showing an embodiment of a hammer drill according to the present invention.

[0007] A retainer sleeve 2 for guiding the tip tool 1
Are locked to the cylinder 3 by the needle pin 4 and guide the outer periphery of the intermediate striker 5. The tip tool 1 having a long groove is locked by a needle roller 6 disposed on the retainer sleeve 2, and the needle roller 6 is held by a needle holder 7. A grip 8 arranged on the outer periphery of the needle holder 7 is locked to the retainer sleeve 2 by a front cap 9. The cylinder 3 is supported by a cylinder case 11 via a bearing 12.
Is provided integrally with the cylinder 3 by a sleeve 13, a sleeve 14, and a tome 15. The outer ring of the bearing 12 is fixed by holding a plate 16 and a cushioning member, for example, a urethane ring 17, with a front cover 18 and screwing the front cover 18 to the cylinder case 11. Further, on the inner periphery of the cylinder 3, a damper holder 20, a damper 21, a damper washer 2
2 are arranged in order, and are fixed by a C-ring 19 so that each comes into contact with the flat portion 5a of the intermediate striker 5. The intermediate striker 5 is disposed between the tip tool 1 and the striker 23, converts the rotational force of a motor (not shown) into a strike force by a motion converter, and converts the strike force through the striker 23 and the like. By transmitting the impact force to the intermediate striker 5, the impact force can be transmitted to the tip tool 1.

When the tip tool 1 is separated from the work material during the work of machining the work piece, the intermediate striker 5 collides with the retainer sleeve 2 as shown in FIG. Occur. This axial force is transmitted from the retainer sleeve 2 to the cylinder 3 via the needle pin 4, and further from the cylinder 3 to the bearing 12, the plate 16, the urethane ring 17
, And can be finally absorbed by the urethane ring 17. The urethane ring 17 is sandwiched between the plate 16 and the front cover 18 with a certain interference in the axial direction, and fixes the bearing 12. The plate 16 has a portion that comes into contact with a side surface of the urethane ring 17 located on the side opposite to the tip tool 1 and a regulating member 16a that can come into contact with the facing surface 17a of the urethane ring 17.
Are integrally formed to form an L-shape. With such a configuration, even when a large force for pulling out the tip tool 1 forward, that is, a large axial force is generated, the amount of compressive deformation of the urethane ring 17 can be restricted above the facing surface 17a. Since the member 16a is provided,
Even if the urethane ring 17 is deformed to the cylinder 3 side, only a predetermined amount is deformed by the regulating member 16a, so that the urethane ring 17 is hardly deformed in the axial direction,
As a result, excessive deformation of the urethane ring 17 can be restricted, and as a result, the present embodiment has an effect that the life of the urethane ring 17 can be improved. Further, the urging ring 17 can be prevented from being thermally expanded by the heat generated at the time of impact and deformed toward the cylinder 3 by the restricting member 16a. When the axial length of the plate 16 is smaller than the axial length of the urethane ring 17, the impact force for a short time is absorbed by the urethane ring 17, and a small load is statically received by mechanical parts other than the urethane ring 17. Therefore, the life of the urethane ring 17 can be further improved.

In the embodiment described above, the regulating member 16a is provided on the plate 16 by integral formation. However, if the regulating member 16a regulates the amount of deformation of the urethane ring 17 toward the cylinder 3, it is separate from the plate. The same effect as described above can be obtained even if a regulating member is provided in the first embodiment. For example, a cylindrical ring may be provided between the bearing 12 and the front cover 18 separately from the plate shown in the related art. Further, in the above-described embodiment, when the urethane ring 17 is deformed, the end of the regulating member 16a does not abut on the side surface of the front cover 18, but the end of the regulating member 16a is By contacting the side surface of the cover 18, the amount of deformation of the urethane ring 17 can be set according to the contact distance. Further, in the embodiment described above, the plate 16
Is smaller than the length of the urethane ring 17 in the axial direction, but it is not always necessary to shorten the length as long as the deformation of the urethane ring 17 does not cause a problem.

[0010]

According to the present invention, the life of the cushioning member can be improved by providing the regulating member for regulating the amount of deformation of the cushioning member.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of a hammer drill according to the present invention.

FIG. 2 is a vertical sectional side view showing a conventional hammer drill.

[Explanation of symbols]

1 is a tip tool, 3 is a cylinder, 5 is an intermediate striker, 12 is a bearing, 16 is a plate, 16a is a regulating member, 17 is a buffer member, 17a is an opposing surface, 18 is a front cover, and 23 is a striker.

Claims (1)

[Claims] 1. An intermediate striker for transmitting an impact force to a tool bit, a cylinder accommodating the intermediate striker, a bearing rotatably supporting the cylinder, and one end provided on a plate provided on a side surface of the bearing. And a cushioning member having the other end in contact with the front cover, wherein the cushioning member has a surface facing the cylinder, and the cushioning member is provided above the facing surface. A striking tool comprising a regulating member for regulating an amount of deformation of the striking tool.