JPH0236962Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The present invention relates to a hydraulic vibration absorbing device used for absorbing hydraulic vibration of a hydraulic circuit of a hydraulic clutch release device, for example. In particular, a body has a first port and a second port connected to a master cylinder and an operating cylinder, respectively, and a stepped cylinder that communicates with both ports at a small diameter portion, and a fluid is supplied to the small diameter portion of the stepped cylinder of this body. A piston that is tightly and slidably fitted to form a hydraulic chamber communicating with both ports, and an end surface of the piston opposite to the hydraulic pressure chamber and a lid plate fixed to the body are interposed. In a hydraulic vibration absorbing device having a rubber cushion member and a plate interposed within the large diameter portion of the stepped cylinder, abnormally high fluid levels may occur due to a failure of the clutch device or blockage of the piping system. When pressure acts on the hydraulic pressure chamber, the cushion member may be excessively deformed and damaged due to the sliding of the piston, or the piston may slide excessively due to damage to the cushion member, causing damage to the working cylinder. The present invention relates to a stopper that limits the displacement of the piston and the plate toward the cushion member so as not to cause a shortage of liquid.

(Prior art) As a conventional device of this kind, for example,
There is one described in Publication No. 104631. As shown in FIG. 3, this rubber cushion member 16 is formed into a cylindrical shape, and a hole is formed in the center of the plate 15.
6 is formed on the end surface of the piston 12, and when the piston 12 and the plate 15 are displaced by a specified amount toward the cushion member 16, the projection 12b extends into the cushion member 16.
2b collides with the cover plate 18 to stop further displacement of the piston 12 and plate 15.

(Problems to be Solved by the Invention) In the conventional device as described above, the outer diameter of the cushion member 16 is limited due to the size constraints of the device, and the volume of the cushion member 16 is increased. If the inner diameter of the cushion member 16 is made smaller in order to increase the spring constant, the piston 1
The cross-sectional area of the protrusion 12b of No. 2 becomes smaller, and the protrusion 12
When b collides with the cover plate 18, the surface pressure between the two becomes extremely high, and the cover plate 18 must be made strong to prevent deformation, which poses a problem in that the weight of the device increases.

Therefore, the present invention attempts to solve the above problem by improving the stopper.

[Structure of the idea]

(Means for Solving the Problems) The measures taken by the present invention to solve the above problems include an annular contact surface formed on the piston on the peripheral wall of the stepped cylinder of the body, or the outer periphery of the side surface of the cushion member of the plate. A ring-shaped stopper is installed to limit the displacement of the piston and plate toward the cushion member due to collision with the cushion member.

(Function) With this configuration, the lid plate does not receive a huge force from the piston, so the lid plate does not need the strength required in conventional devices, and the weight of the device can be reduced compared to conventional devices. It is something.

(Example) Hereinafter, the present invention will be further clarified by describing an example of the present invention based on the drawings.

First, one embodiment of FIG. 1 will be explained. 10 is the body, and port 10 is connected to the master cylinder M.
a, a port 10b connected to a clutch release cylinder (operating cylinder) L, and a stepped cylinder 10c. The small diameter portion of stepped cylinder 10c communicates with ports 10a and 10b at its left end.

A piston 12 equipped with a rubber ring-shaped cup seal 11 is attached to the small diameter portion of the stepped cylinder 10c.
are slidably fitted together, whereby the body 10
A hydraulic chamber 13 that communicates with ports 10a and 10b therein.
is formed. A weak spring 14 is arranged within this hydraulic pressure chamber 13 to urge the piston 12 to the right.

There is a plate 1 inside the large diameter part of the stepped cylinder 10c.
5 and a rubber cushion member 16 are arranged. The cushion member 16 is fixed to the plate 15, and is connected to the stepped portion 10d of the body 10.
A precompression is applied to the cushion member 16 by tightening it with a cover plate 18 fixed with bolts 17.

The stopper that limits the displacement of the piston 12 and plate 15 toward the cushion member 16 is a snap ring (ring-shaped stopper) fitted into an annular groove 10e in the peripheral wall of the large diameter portion of the stepped cylinder 10c.
19. When the piston 12 and the plate 15 are displaced by a specified amount toward the cushion member 16, the outer peripheral portion of the side surface of the cushion member 16 of the plate 15 collides with the snap ring 19, thereby stopping further displacement of the piston 12 and the plate 15.

In another embodiment in FIG. 2, the portion of the piston 12 on the plate 15 side is formed to have a small diameter, and the stepped cylinder 10
When the snap ring 19 is fitted into the annular groove 10e formed in the peripheral wall of the small diameter portion of c, and the piston 12 and plate 15 are displaced by a specified amount toward the cushion member 16, the annular contact surface 12a of the piston 12 collides with the snap ring 19. Further displacement of the piston 12 and plate 15 is stopped upon contact.

[Effect of idea]

As explained above, the present invention has the effect of reducing the weight of the device compared to conventional devices, and since the cushion member can be made solid, it is possible to configure a device with a large spring constant of the cushion member. This has the advantage that it can be made smaller than conventional devices.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of one embodiment of the present invention, FIG. 2 is a cross-sectional view of another embodiment of the present invention, and FIG. 3 is a cross-sectional view of a conventional device. Explanation of symbols, 10...Body, 10a, 10b
...Port, 10c...Stepped cylinder, 12...
Piston, 13... Hydraulic pressure chamber, 15... Plate,
16...Cushion member, 18...Lid plate, 19...
... Snatsupring (ring-shaped stoppa).

Claims (1)

[Scope of utility model registration request] A body that has a first port and a second port that are connected to a master cylinder and an operating cylinder, respectively, and a stepped cylinder that communicates with both ports through a small diameter portion, and a small diameter portion of the stepped cylinder of this body that is liquid-tight. and a piston that is slidably fitted to form a hydraulic chamber that communicates with both ports, and a lid plate that is fixed to the body and an end surface of the piston opposite to the hydraulic pressure chamber. A hydraulic vibration absorber comprising a cushion member made of rubber and a plate interposed within the large diameter portion of the stepped cylinder,
A ring shape is formed on the circumferential wall of the stepped cylinder to limit displacement of the piston and the plate toward the cushion member by contact with an annular contact surface formed on the piston or an outer peripheral portion of the side surface of the cushion member of the plate. A hydraulic vibration absorber equipped with a stopper.