JPH074458A - Bush form vibration control rubber - Google Patents

Abstract

PURPOSE:To provide a bush form vibration control rubber which can eliminate a gap between the engaging surface of the engaging claw on the outer periphery of an outer tube, and the engaging receiver of a cylindrical holder, and generates no shear which causes the generation of a strange sound between the outer tube and the cylindrical holder. CONSTITUTION:A rigid body inner tube 1 and a rigid body outer tube 3 having an engaging flange 8 at the base side are combined by a vibration proof rubber 5, and an engaging claw 7 to engage with the upper end edge 9a of a cylindrical holder 9 is formed at the top end side of the rigid body outer tube 3. Plural through holes 23 are formed on the engaging surface side of the engaging claw 7 formed on the outer peripheral wall of the rigid body outer tube 3, and the engaging surface is covered by a rubber layer 25 extending from the vibration proof rubber 5 through the through holes 3. And the rubber layer 25 has the thickness almost same as the thickness of the maximum gap generated between the engaging surface 7a of the engaging claw 7, and the upper end edge 9a of the cylindrical holder 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bush type vibration proof rubber. In particular, the present invention is suitable for a body mount cushion (anti-vibration mount) of front and rear suspension members in an automobile.

Here, a body mount cushion whose rigid outer cylinder portion is divided into two parts will be mainly described as an example, but the present invention is not limited to this.

[0003]

2. Description of the Related Art An example of a bush type vibration proof rubber used as a conventional body mount cushion is shown in FIGS.

The rigid body tubular portion 1 and the rigid body outer tubular portion 3 are connected by a vibration-proof rubber portion 5, and the rigid body tubular portion 3 is divided into a pair of half tubular portions 3a, 3a. The semi-cylindrical portions 3a and 3a are separated from each other before press-fitting into the tubular holder 9, and the semi-cylindrical portions 3a and 3a are close to each other after press-fitting into the tubular holder 9. The rigid outer cylindrical portion 3 is formed with a plurality of (four in the illustrated example) engaging claw portions 7 that engage with the upper edge (engaging receiving portion) 9a of the cylindrical holder 9 on the tip side. The base portion side is an engagement flange portion 8 so as to engage with the lower end portion of the cylindrical holder 9. In addition, the tip end side of the rigid outer cylindrical portion 3 is formed in a squeezed shape so that the vibration-proof rubber can be easily inserted into the cylindrical holder 9.

The anti-vibration rubber is press-fitted into the cylindrical holder 9 formed integrally with the suspension member (sub-frame) 11 from below, and the anti-vibration rubber is attached to the bolt 15 protruding from the vehicle body 13. Through the washer 17 and the nut 19 through the washer 17.
The vehicle body 13 and the sub-frame 11
Is intervened between. In the figure, 21 is a stopper rubber.

The anti-vibration rubber has a function of attenuating vibrations such as vertical movements and vertical vibrations which act on the sub-frame while the vehicle is running, and transmit the vibrations to the vehicle body.

At this time, the anti-vibration rubber at the time of bouncing tends to come out upward, but this is prevented by the engagement of the lower end of the tubular holder 9 and the engaging flange portion 3b of the rigid outer tubular portion 3. . Further, at the time of rebound, the anti-vibration rubber tries to come out downward, but this is prevented by the engagement between the engaging claw portion 7 and the upper end edge (engagement receiving portion) 9a of the tubular holder 9.

A known technique similar to the above is described in Japanese Utility Model Publication No. 57-126649.

[0009]

However, since the cylindrical holder 9 is usually formed by press working and has a large manufacturing dimensional tolerance, the engaging claw portion 7 is usually formed at a higher position in consideration of the tolerance ( The cylindrical holder 9 is pressed with a minus tolerance.).

Therefore, a gap G of about 1 mm is provided between the engaging surface 7a of the engaging claw portion 7 and the upper edge 9a of the cylindrical holder 9.
May occur. It has been found that the presence of this gap causes relative displacement between the outer periphery of the outer cylindrical portion 3 and the cylindrical holder 9 to cause abnormal noise (squeak noise).

In view of the above, the present invention can eliminate the gap between the engaging surface of the engaging claw portion on the outer periphery of the outer tubular portion and the engaging receiving portion of the tubular holder, and the outer tubular portion and the tubular portion can be eliminated. An object of the present invention is to provide a bush-type vibration-proof rubber that does not cause a gap that causes abnormal noise between the bush-shaped vibration-proof rubber and the holder.

[0012]

The bush type vibration-proof rubber of the present invention solves the above problems by the following constitution.

A rigid body outer cylinder portion and a rigid body outer cylinder portion having an engaging flange portion on the base side are connected by a vibration-proof rubber portion, and the rigid body outer cylinder portion is a cylindrical holder on the tip side. In a bush type vibration-proof rubber having a configuration in which an engaging claw portion that engages with the engaging receiving portion is formed, a plurality of engaging claw portions formed on the outer peripheral wall of the rigid outer cylindrical portion are provided on the engaging surface side. A through hole is formed, and the engagement surface is covered with a rubber layer extending from the anti-vibration rubber portion through the through hole, and the rubber layer is formed between the engagement surface of the engaging claw portion and the engagement receiving portion of the tubular holder. It is characterized by having the same thickness as the maximum gap generated between them.

[0014]

The operation and effect of the present invention is as follows.
With the above configuration, the following actions and effects are achieved.

The engagement surface 7a of the engagement claw portion 7 formed on the outer peripheral wall of the rigid outer cylindrical portion 1 is covered with the rubber layer 25, and the rubber layer 23 is formed.
Has substantially the same thickness as the maximum gap generated between the engaging surface 7a of the engaging claw portion 7 and the engaging receiving portion 9a of the cylindrical holder 9. Therefore, the gap G between the engagement surface 7a of the engagement claw portion 7 and the upper end edge 9a of the cylindrical holder 9 is equal to the rubber layer 25.
Filled with.

Therefore, even when the anti-vibration rubber receives a force to pull out downward at the time of rebound of the automobile, there is a slight displacement between the rigid outer cylindrical portion and the cylindrical holder as in the conventional case. No noise is generated, and no abnormal noise (squeak noise) is generated.

[0017]

EXAMPLES The present invention will now be described in detail based on examples. The same parts as those in the above-described example are designated by the same reference numerals, and the description thereof will be omitted in whole or in part.

Similar to the above-mentioned example, the rigid body tubular portion 1 and the rigid outer tubular portion 3 having the engaging flange portion 3b on the base portion side (one end side).
Is connected to the rigid outer cylindrical portion 3 by a vibration-proof rubber portion 5.
Is divided into a pair of semi-cylindrical parts 3a, 3a, the semi-cylindrical parts 3a, 3a are separated from each other before press-fitting into the tubular holder 9, and the semi-cylindrical parts 3a, 3a are press-fitted into the tubular holder 9 after being pressed. In this configuration, they are close to each other. Further, the rigid outer cylindrical portion 3 has an engaging claw portion 7 that engages with the engaging receiving portion 9a of the cylindrical holder 9 on the distal end side.
Is formed, and the base portion side is an engagement flange portion 8 so as to engage with the lower end portion of the cylindrical holder 9.

Here, the separation distance d between the semi-cylindrical parts 3a and 3a.
Is 3 to 5 mm when the outer peripheral radius r of the semi-cylindrical portions 3a and 3a is 25 mm. Further, in the illustrated example, the rigid tubular portion 1 is a steel pipe and the rigid outer tubular portion 3 is glass fiber reinforced nylon, but the molding material for the inner tubular portion 1 and the outer tubular portion 3 has a required strength. There is no particular limitation, and metal materials such as steel and aluminum (including castings), reinforced plastics, ceramics and the like are optional. The anti-vibration rubber part is formed of natural rubber, ethylene propylene rubber, or the like, and is usually insert-molded by injection, transfer, etc., using the rigid body tubular portion 1 and the rigid body tubular portion 3 as inserts. So far,
It is substantially the same as the conventional example. The shapes of the inner tubular portion 1 and the outer tubular portion 3 are both cylindrical in the illustrated example, but the outer tubular portion 3
The shape may be an elliptical shape or a rectangular tube shape.

In the above-mentioned structure, in this embodiment, as shown in FIG.
As shown in FIG. 6, a plurality of through holes 23 are formed in the peripheral wall of the rigid outer cylindrical portion 3 on the engaging surface 7 a side of the engaging claw portion 7.
The engaging surface is covered with a rubber layer 25 extending from the anti-vibration rubber portion. At this time, the rubber layer 25 has substantially the same thickness (usually 1.0 to 3 mm) as the maximum gap generated between the engaging surface 7a of the engaging claw portion 7 and the engaging receiving portion 9a of the tubular holder 9.
Have.

The rubber layer is usually formed during molding of the vibration-proof rubber portion, but the vibration-proof rubber may be pushed out into the cylindrical holder when it is pressed.

It is needless to say that the present invention can be applied to a vibration-proof rubber in which the rigid outer cylindrical portion 3 is not a divided body, as shown in FIG. It can also be applied to a vibration-proof rubber having a structure in which the engaging claw portions 7 are continuous.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a conventional bush-type anti-vibration rubber.

FIG. 2 is a vertical cross-sectional view showing a state where the anti-vibration rubber of FIG. 1 is press-fitted into a holder.

FIG. 3 is an enlarged sectional view of a part III in FIG.

FIG. 4 is a vertical cross-sectional view showing a state before press-fitting the holder of the vibration-proof rubber according to the embodiment.

5 is a plan view of FIG.

FIG. 6 is an enlarged sectional view of a VI portion in FIG.

FIG. 7 is a plan view showing an example in which the rigid outer cylinder part is also applied to a vibration isolating rubber which is not a divided body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rigid-body cylinder part 3 Rigid-body cylinder part 5 Anti-vibration rubber part 7 Engaging claw part 7a Engaging surface 8 Engaging flange part 9 Cylindrical holder 9a Upper end edge (engaging receiving part) of the cylindrical holder 23 Rubber layer formation Through hole 25 rubber layer

Claims (1)

[Claims] 1. A vibration-proof rubber portion is connected between a rigid body tubular portion and a rigid body outer tubular portion having an engaging flange portion on the base side, and the rigid body outer tubular portion is provided on the tip side. In a bush type vibration-proof rubber having a structure in which an engaging claw part that engages with an engaging receiving part of a cylindrical holder is formed, a plurality of bushes are provided on an engaging surface side of the engaging claw part of a peripheral wall of the rigid outer cylinder part. A through hole is formed, and the engagement surface is covered with a rubber layer extending from the anti-vibration rubber portion through the through hole, the rubber layer engaging the engagement surface of the engagement claw portion and the cylindrical holder. A bush type anti-vibration rubber having a thickness substantially equal to a maximum gap generated between the bush and the receiving portion.