JPS59156677A - Impact moving tool - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact power tool such as a hydraulically driven drill or a hydraulic breaker, and more particularly to an impact power tool that can improve operating performance.

FIG. 1 is a side sectional view showing an example of a conventional impact power tool.

In this figure, 1 is a main body forming an outer shell, 2 is a piston that is disposed within this main body 1 and can freely reciprocate through hydraulic pressure, 3 is attached to the main body 1, and one end of the piston 2 A rigid member, such as a chisel, is placed opposite the. Further, 4.5 is a groove formed in the main body 1, and 6.
Reference numerals 7 denote pressure receiving chambers formed between the main body 1 and the piston 2, and the cross-sectional area of the pressure receiving chamber 7 is set to be larger than the cross-sectional area of the pressure receiving chamber 6.

8 is the main circuit that can supply pressure oil to the pressure receiving chamber 6, 9 is the pressure receiving chamber 7
10 is a pressure oil supply port connected to a hydraulic pump (not shown); 11 is a pressure oil discharge port connected to a tank (not shown); 12 stores high pressure oil; 13 is a low-pressure Akiemulator for absorbing pulsation. Further, 14 is a switching valve arranged between the supply port 10 and the discharge port 11 and the main circuit 9, and is operated by pilot pressure. One end 14a of the switching valve 14 is connected to the groove 4 via a check valve 15 and a pilot circuit 16, and is connected to the groove 4 via a pilot circuit 17.
It is connected to the groove 5 via. The other end 14b of the switching valve 14 is connected to the main circuit 8 via a pilot circuit 18. Note that one end 1 of the switching valve 14
The pressure receiving area of 4a is set larger than the pressure receiving area of the other end 14b.

In the impact power tool configured in this manner, when pressure oil is supplied from the supply port 10 when the piston 2 is located to the left of the position shown in FIG. It is led to the pilot circuit 16 via the main circuit 8, the pressure receiving chamber 6, and the groove 4. In this case, pilot pressure from the pilot circuit 16 is introduced to the end 14a of the switching valve 14, and the end 14a
Pilot pressure from the pilot circuit 18 is introduced to b, but since the pressure receiving area of the end 14b is smaller than the pressure receiving area of the end 14a, the switching valve 14 is in the state shown in FIG.
That is, the main circuit 9 is connected to the discharge port 11.

As a result, the output of the pressure receiving chamber 6 becomes larger than the pressure of the receiver 11TEv7, and the piston 2 moves to the right, for example, the first
The state shown in the figure will be reached. At this time, the main circuit 8 and the groove 4 are cut off by the piston 2, while the groove 5 and the pressure receiving chamber 7 are communicated with each other, so that the pilot air passage 17 is connected to the discharge port 11, that is, the tank. As a result, the switching valve 14 is switched to the right position in FIG. 1 by the pilot pressure of the pilot circuit 18, and the supply port 10 and the main circuit 9 are brought into communication. This allows the pressure oil to flow through the switching valve 14 and the main circuit 9.
However, since the cross-sectional area of the pressure-receiving chamber 7 is set larger than the cross-sectional area of the pressure-receiving chamber 6, the piston 2 is It moves to the left in response to a force corresponding to , collides with chisel 3, and generates an impact force. Thereafter, similar operations are repeated. Note that the chisel 3 performs the work of crushing rocks and the like by the generated impact force, for example.

By the way, in the impact-actuating tool configured in this way, the moving speed of the piston 2 tends to be slower than the conventionally proposed tools that operate the piston 2 using air pressure, and therefore, It is not possible to generate a sufficiently large impact force.

2 and 3 are explanatory diagrams showing another conventional example proposed to eliminate the above-mentioned problems. FIG. 2 is a side sectional view drawn corresponding to FIG. 1, and FIG. This figure is an enlarged side sectional view showing the vicinity of the head of the piston in FIG. 2.

In the examples shown in FIGS. 2.3, the basic configuration is almost the same as that shown in FIG. 1 described above, but the configuration near the head of the piston 2 is different. That is, a gas chamber 19 is provided in a portion of the main body 1 near the head of the piston 2, and this gas chamber IIC is filled with gas such as high pressure nitrogen gas. Two sealing members 21 are arranged between the body 1 and the piston 2 to prevent the gas inside from leaking to the outside of the body 1. In addition, in FIG. 3, 22 is a sealing member that prevents pressure oil from leaking to the outside of the main body 1, n is the sealing member side, and 21 is a drain hole that discharges gas or oil leaking from the sealing member n. .

The operation of the impact power tool configured in this way is basically the same as that shown in FIG. 1 described above, but in the tool shown in FIG. 2
．． When the piston 2 moves to the right in Fig. 3, the gas in the gas chamber 19 is compressed to a higher pressure, and when the piston 2 moves to the left in Figs. 1, it is possible to increase the moving speed of the piston 2 in the leftward movement compared to the tool shown in FIG. 1, and therefore, it is possible to generate a larger impact force.

However, in the conventional impact power tool shown in Fig. 2.3, it is necessary to provide at least two sets of seal members and grooves for the seal members to seal gas and oil.
In particular, it is generally very difficult to seal high-pressure gas, and the number of manufacturing steps tends to increase. Further, since the sealing member 2I is constantly subjected to high pressure, the life of the sealing member 21 is short and its durability is likely to deteriorate. As a result, the piston 2 is likely to malfunction due to gas leakage.

The present invention has been made in view of the actual situation in the prior art, and an object of the present invention is to provide an impact power tool that can ensure a sufficient moving speed of the piston without providing a seal member.

Hereinafter, the impact power tool of the present invention will be explained based on the drawings. FIG. 4 is a side sectional view showing essential parts of an embodiment of the present invention.

In this figure, the prisoner is a space provided in the main body 10 located near the end (head) of the piston 2, and 245 is a telescopic bellows disposed within this space 24, such as a metal thin film. It was prepared by A concentric protrusion is formed in the center of one end of the bellows 5.
This protrusion 26 is removably engaged with a recess n formed in the center of the head of the piston 2. The other end of the bellows 5 is attached to the cover field forming the condyle of the body 10. High pressure gas is sealed inside the bellows δ. Further, the wall surface forming the above-mentioned space 24 is formed into a tapered surface 29 such that the diameter of the portion near the cover fat is large and the diameter of the portion near the piston 2 is small. A portion forming the outside of the bellows 25 in the space is filled with viscous fluid. In addition, Shu is main body 1
This hole is formed in the space 24 and communicates with the space 24 for the inflow and outflow of viscous fluid. In this embodiment, the high-pressure gas is sealed inside the bellows 5 which has sufficient strength, so there is no need for a sealing member to prevent gas leakage, and the gap between the piston 2 and the main body 1 can be reduced. By setting it to a sufficiently small size, it is possible to eliminate the seal member for preventing oil M leakage. The other basic configuration is the same as that shown in FIG. 1, for example.

In one embodiment constructed in this manner, when the piston 2 moves in the right direction in FIG. The bellows 5 contracts through this, and the gas inside the bellows 5 is compressed and becomes higher pressure.
When the piston 2 moves to the left in FIG.
Piston 2 and bellows δ including 6 and recess n
Since the pressure of the gas in the bellows portion is applied to the piston 2 through each end of the piston 2, the moving speed of the piston 2 in the leftward direction can be made sufficiently high. In addition, since high-pressure gas is inserted into the bellows part, which has sufficient strength, and no sealing member is provided, there is no need to process grooves for the sealing member or install the sealing member, and the seal Deterioration in durability of the members and malfunction of the piston 2 will not occur.

Furthermore, since the piston 2 and the bellows 5 are configured to be detachable via the recess M and the protrusion 26, assembly work can be easily performed.

Further, the volume of the portion 31 formed on the outer peripheral portion of the bellows 5 and having a triangular cross section increases as the piston 2 moves to the left in FIG. 4, that is, as the bellows 6 expands. The viscous fluid in the space u flows toward the portion 31 from the portion 32 near the taper rotation. In addition,
The viscous fluid that is insufficient due to this inflow operation flows into the space rows between the holes of the main body 1. If the piston 2 suddenly stops while moving to the left, the bellows 5 will move further due to its inertia, that is, each of the peaks that make up the bellows 5 will move toward the left in a dense manner. , the volume of the portion 31 () located close to the piston 2 decreases. As a result, the viscous fluid flows from the section 31 to the section 3.
Be ejected towards 2. Incidentally, the viscous fluid remaining due to this discharge operation flows out of the main body 1 through the holes in the space part. In this way, if the piston 2 suddenly stops while moving to the left in FIG. 4, the piston 2
The piston 2 is caused by the resistance due to the discharge of viscous fluid due to the decrease in volume of the portion 31 located on the side closer to the piston 2, and the resistance received from the viscous fluid on the sloped surface of the mountain of the bellows 5 located on the side farther from the piston 2. The volume reduction rate of the portion 31 located on the side closer to the piston 2 is regulated, and accordingly, collision between the peaks of the bellows 6 on the side closer to the piston 2 is prevented, and the peaks of the bellows 6 on the side closer to the piston 2 are prevented from colliding with each other. Deformation of the part is prevented.

In addition, since the space U is formed by a tapered member whose diameter decreases as it approaches the piston 2, the volume of the portion 320 decreases as it approaches the piston 2, and the bellows 5 changes from a contracted state to an expanded state. In this case, the flow speed of the viscous fluid into the portion 31 can be increased, and as described above, the portion 3 which is caused by sudden stopping when the piston 2 moves leftward in FIG.
When discharging the viscous fluid from 1 to the section 32, a greater resistance can be generated in the section 31 close to the piston 2, thus contributing to regulating the volume reduction rate of the section 31.

In the above-mentioned embodiment, the piston 2 is provided with the four parts n and the bellows 5 is provided with the protruding part, but on the contrary, the piston 2 is provided with the protruding part and the bellows 5 is provided with the recessed part n. It is also possible to do so.

Further, in the above embodiment, the wall surface forming the space row is formed into a tapered surface, but the wall surface is not formed into a tapered surface, but has a cylindrical inner surface that follows the outer periphery of the bellows 5. You can also do it.

As described above, the impact power tool of the present invention is configured such that a bellows is interposed between the piston and the main body, and the piston is moved using the pressure of the high-pressure gas sealed within the bellows. Therefore, it is possible to ensure a sufficient operating speed of the piston, which has the effect of generating a large impact force. Further, since no seat member is provided, the number of manufacturing steps can be reduced compared to the conventional method, and durability can be improved, and stable operation of the piston can be ensured over a long period of time. Further, since the piston and the bellows are engaged with each other in a layered manner, assembly work can be easily performed. Furthermore, since the viscous fluid is brought into contact with the outside of the bellows portion, deformation of the bellows 5 when the piston suddenly stops can be reliably prevented.

[Brief explanation of drawings]

Figure 1 is a side sectional view showing an example of a conventional 5F power tool;
Figures 2 and 3 are explanatory diagrams showing another example of the conventional Senfh$ power tool. Figure 2 is a side sectional view, and Figure 3 is an enlarged view of the vicinity of the head of the piston in Figure 2. FIG. 4 is a side sectional view showing a main part of an embodiment of the impact power tool of the present invention. 1...Body, 2...Piston, 3...
... Chisel (rigid member), Sae ... Space part,
5...Bellows, bellows, protrusion, etc.
... recess, ah... cover, addition...
・Tapered surface, (capital)...hole. Figure 1 Figure 2 / 19

Claims (1)

[Claims] 1. A main body forming an outer shell, and a main body disposed within this main body,
The method includes a piston that can freely reciprocate through hydraulic pressure, and a rigid member that is attached to the main body and is arranged opposite to the piston, and when the piston reciprocates, the piston collides with a steel member. An impact power tool that generates an impact force by: a space formed in a portion of the main body located near the head of the piston, and a space disposed in the space and having one end attached to the piston;
A bellows whose other end is attached to the main body is provided, high-pressure gas is sealed inside the bellows, and a portion of the space forming the outside of the bellows is filled with a viscous fluid. Moving tools.