JPH05126186A - Vibration-proof bush - Google Patents

Abstract

PURPOSE:To achieve both maneuvering stability and a cushion effect by inserting an insert between an outer cylinder and an inner cylinder disposed concentrically, disposing a rubber layer and a sliding layer at an inner circumferential surface of the insert in order, and disposing vibration-proof rubber bodies on both side of the insert. CONSTITUTION:A relatively long inner cylinder 1 is inserted to an axial center part inside an outer cylinder 2, and a ring-like insert 3 is pressed into a center part between these. A rubber layer 5 of a constant thickness is bound to an inner circumferential surface of the insert 3, and a sliding layer 6 of a small friction resistance is formed on an inner circumferential surface of the insert 3. An inner diameter of the rubber layer 5 is set smaller than an outer diameter of the inner cylinder 1, so the inner cylinder 1 is penetrated to enlarge the diameter of the rubber layer 5 to get it in contact with the sliding layer 6. Vibration-proof rubbers 4A, 4B are inserted from both end aperture parts of the outer cylinder 2 between the outer cylinder 2 and the inner cylinder 1. Vibration inputted to the inner cylinder 1 is thus transmitted through the sliding layer 6 to the rubber layer 5 to be absorbed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping bush, and more particularly to a vibration damping bush suitable for holding a suspension arm of a vehicle suspension.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional anti-vibration bush used for this type of application, which includes an outer cylinder 2 fixed to a vehicle frame and a suspension arm S inserted through the center thereof.
And an inner cylinder 1 having one end thereof connected, and a vibration-proof rubber body 6 having a constant thickness is formed in a cylindrical shape on the outer periphery of the inner cylinder 1, and the vibration-proof rubber body 8 is press-fitted and fixed in the outer cylinder 2. is there.

[0003]

By the way, the above-mentioned anti-vibration rubber body has a large rigidity in the direction perpendicular to the axis of the suspension arm in order to ensure steering stability, and is sufficiently small in the axial direction in order to enhance the cushioning property. It must have spring properties.

However, in the conventional vibration-proof bushing described above, if the spring constant of the vibration-proof rubber body is increased in order to ensure steering stability, the cushioning property will be impaired, and it is difficult to achieve both steering stability and cushioning property. It was

The present invention has been made to solve the above problems, and an object of the present invention is to provide an anti-vibration bush capable of achieving both steering stability and cushioning properties.

[0006]

The structure of the present invention will be described. The outer cylinder 2 has an inner cylinder 1 and an outer cylinder 2 which are concentrically arranged and are respectively connected to a vibrating body. The ring-shaped insert 3 is further projected toward the center of the outer periphery of the inner cylinder 1, a rubber layer 5 having a constant thickness is joined to the inner peripheral surface of the insert 3, and the inner peripheral surface of the rubber layer 5 has a small friction resistance. An inner cylinder 1 is formed by forming a sliding layer 6 so as to contact the sliding layer 6 and position the inner cylinder 1 in a penetrating position, and which is separated from both end portions of the inner circumference of the outer cylinder 2 and the end surface of the insert 3 by a predetermined dimension m. Ring-shaped anti-vibration rubber bodies 4A and 4B are jointly arranged between the both ends of the outer circumference.

[0007]

In the above structure, when vibration in the direction perpendicular to the axis is input, the inner cylinder 1 is prevented from moving because the outer peripheral surface of the inner cylinder 1 is in contact with the rubber layer 5 via the sliding layer 6. ..
If the thickness of the rubber layer 5 is reduced, the rigidity of the vibration-proof bushing in this direction is kept sufficiently large to maintain good steering stability, and the alignment can be kept constant because no rattling occurs. .. Also, the inner cylinder 1 and the insert 3
Since it does not hit directly, the generation of abnormal noise is prevented and the riding comfort is not impaired.

When axial vibration is input, the inner cylinder 1 comes into contact with the sliding layer 6 and freely reciprocates within the insert 3 within the predetermined dimension in accordance with the vibration input. The spring force of the anti-vibration bush at this time is determined only by the anti-vibration rubber bodies 4A and 4B, and if the spring constant of the anti-vibration rubber bodies 4A and 4B is set sufficiently small, good cushioning properties can be obtained. The inner cylinder 1 is also capable of torsional displacement, which also ensures cushioning properties.

[0009]

[Embodiment 1] In FIG. 1, an inner cylinder 1 which is slightly longer than the outer cylinder 2 is disposed at the axial center of the outer cylinder 2, and a ring-shaped insert 3 is press-fitted and fixed in the center of the outer cylinder 2. I am doing it.
The insert 3 is made of a resin material or a metal material.

A rubber layer 5 is bonded to the inner peripheral surface of the insert 3 with a constant thickness, and a sliding layer 6 having a small frictional resistance is formed on the inner peripheral surface of the rubber layer 5. The sliding layer 6 is formed, for example, by bonding a braided liner made of resin fiber such as Teflon having good slidability to the inner peripheral surface of the rubber layer 5. The inner diameter of the rubber layer 5 is made smaller than the outer diameter of the inner cylinder 1 by a certain amount, and the inner cylinder 1 is pushed through the inside of the rubber layer 5 to penetrate it while being in contact with the sliding layer 6. The liner forming the sliding layer may have a two-layer structure in which the contact surface with the inner cylinder is Teflon fiber and the bonding surface with the rubber layer is Tetron fiber.

Anti-vibration rubber bodies 4A and 4B are inserted between both openings of the outer cylinder 2 and the inner cylinder 1. Anti-vibration rubber body 4
A and 4B are ring bodies that expand and incline like an umbrella,
Metal sleeves 71 and 72 are joined to the inner and outer peripheral surfaces thereof, and these sleeves 71 and 72 are press-fitted and fixed to the inner circumference of the outer cylinder 2 and the outer circumference of the inner cylinder 1. The sleeves 71, 72 and the end surface of the insert 3 are separated by a predetermined dimension m.

There are provided stopper plates 11 and 12 which are in contact with both end surfaces of the inner cylinder 1 and which have openings having substantially the same diameter as the inner cylinder 1. A stopper rubber 13 is projectingly formed so as to face the end surface of the cylinder 2.

In the vibration-proof bush having the above structure, the inner cylinder 1
When a vibration in the direction perpendicular to the axis is input from a suspension arm (not shown) that is inserted and fixed in, the outer circumference of the inner cylinder 1 contacts the inner circumference of the rubber layer 5 via the sliding layer 6, and displacement is prevented. If the rubber layer 5 is appropriately thinned, the rigidity of the vibration-proof bush is maintained sufficiently high in this direction, and steering stability is secured.

When axial vibration is input from the suspension arm, the inner cylinder 1 freely slides within the sliding layer 6 within the range of the dimension m, and the spring constant of the vibration-proof bush at this time is the vibration-proof rubber body. The size is sufficiently small due to only the deformation of 4A and 4B. Thus, good cushioning properties are secured in this direction, and riding comfort is improved. In addition, the inner cylinder 1 can be twisted and displaced, which also provides good cushioning properties.

At this time, since the sliding layer 6 is elastically brought into contact with the outer circumference of the inner cylinder 1 by the rubber layer 5 behind it, no rattling or noise is generated when the inner cylinder 1 is moved. In addition, the elasticity of the rubber layer 5 prevents the cushioning property in the axial direction from being lowered.

Further, against excessive vibration input in the axial direction, the end surface of the outer cylinder 2 and the stopper rubber 13 come into contact with each other to prevent the vibration-proof rubber bodies 4A and 4B from being excessively deformed and prevented from being damaged. ..

[0017]

Second Embodiment In the above embodiment, the stopper plate 11,
The stopper rubber 13 is provided on the 12, but as shown in FIG.
One end of the sleeve 72 is formed as a flange portion 721 that bends along the end surface of the outer cylinder 2, and the vibration-proof rubber body 4A,
By extending a part of 4B to form the stopper rubber 41, manufacturing becomes simpler.

[0018]

As described above, according to the vibration-proof bushing of the present invention, it is possible to simultaneously realize a large rigidity in the axial direction and a sufficiently small spring characteristic in the axial direction. And the ride comfort can be satisfied well.

[Brief description of drawings]

FIG. 1 is an overall vertical cross-sectional view of an anti-vibration bush showing an embodiment of the present invention.

FIG. 2 is an overall vertical cross-sectional view of an anti-vibration bush showing another embodiment of the present invention.

FIG. 3 is an overall vertical sectional view of an anti-vibration bush showing a conventional example.

[Explanation of symbols]

 1 Inner Cylinder 2 Outer Cylinder 3 Insert 4A, 4B Anti-vibration Rubber Body 5 Rubber Layer 6 Sliding Layer

Claims (1)

[Claims] 1. An inner cylinder and an outer cylinder, which are concentrically arranged and are respectively connected to a vibrating body, and project a ring-shaped insert from a central portion of an inner periphery of the outer cylinder toward a central portion of an outer periphery of the inner cylinder. At most, a rubber layer having a constant thickness is joined to the inner peripheral surface of the insert to form a sliding layer having a small friction resistance on the inner peripheral surface of the rubber layer, and the inner cylinder is pierced in contact with the sliding layer. The ring-shaped anti-vibration rubber bodies are jointly arranged between the both ends of the inner circumference of the outer cylinder and the both ends of the outer circumference of the inner cylinder which are separated from the insert end surface by a predetermined dimension. Swing bush.