JPH06241269A - Liquid-filling vibration control bush - Google Patents

Abstract

PURPOSE:To maintain the durability of a vibrationproof rubber body simply in terms of structure and inexpensively by dispensing with a separate rubber stopper body. CONSTITUTION:A rubber block pierced through and embedded with an inner cylinder 2 is installed on a car frame 5, forming it into a vibro-isolating rubber body 1. A main liquid chamber A setting the double end parts to both side walls is formed in a lower half part of this rubber body 1, making it connect to a sub-liquid chamber B using a rubber membrane 3 as a chamber wall via a throttle passage F. An almost inverted U-shaped bracket 4 lower in height than the vibro-isolating rubber body 1 is installed so as to cover an outer boundary of this rubber body 1, and when the bracket 4 is locked to a car frame 5, the rubber body 1 is pressed downward by the top wall 41, whereby both side walls of the main liquid chamber A are compressed and deformed. At the time of vibration inputting, since the top wall 41 of the bracket 4 serves as stopper and thereby any displacement upward the inner cylinder 2 is regulated, vertical compressive state in the side wall will in no case be eliminated at all, so that sufficient durability is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-filled anti-vibration bush for damping vibration by circulating a filled liquid in a throttle channel.

[0002]

2. Description of the Related Art An anti-vibration bush, in which an inner cylinder having a vibrating body connected and fixed thereto is embedded in a vibration-proof rubber body and the vibration-proof rubber body is held by a tubular bracket, has a simple structure and excellent durability. Therefore, it is often used for vibration isolation of various parts of the vehicle.

In recent years, in this type of vibration-proof bush, a liquid chamber is formed in a vibration-proof rubber body, and a filled liquid is circulated in a throttle channel in response to a vibration input so that a sufficient vibration damping force can be obtained. What has been done is proposed.

In this case, since the side wall of the liquid chamber located at the end face of the block-shaped anti-vibration rubber body is relatively thin, there is concern that its durability may be reduced. Therefore, for example, Japanese Patent Laid-Open No. 4-
In the 102741 publication, a rubber stopper plate is provided so that the displacement of the inner cylinder at the time of vibration input is restricted within a certain range in which the side wall is appropriately compressed.

[0005]

However, in the above-mentioned conventional structure, since it is necessary to separately manufacture the rubber stopper plate and adjust the assembling, there is a problem that the manufacturing cost is high.

An object of the present invention is to solve the above problems, and an object thereof is to provide a liquid-filled anti-vibration bush having a simple structure and a low cost, which does not require a separate rubber stopper body.

[0007]

To explain the structure of the present invention, a rubber block is provided on a substrate 5 to form a vibration-proof rubber body 1, and an inner cylinder for connecting the vibration body 6 to the vibration-proof rubber body 1. 2 is embedded through, and a main liquid chamber A is formed in the lower half portion of the vibration-proof rubber body 1 with both end faces as both side walls 11 and 12, and the main liquid chamber A is formed by a freely deformable chamber wall 3. Is made to communicate with the auxiliary liquid chamber B via the throttle flow passage F, and the height of the vibration-proof rubber body 1 is high.
A substantially inverted U-shaped bracket 4 which is lower than the above is provided so as to cover the outer circumference of the vibration-proof rubber body 1, and the bracket 4 is attached to the base body 5.
When it is fixed to the main liquid chamber A, the vibration damping rubber body 1 is pressed downward by the top wall 41 to compressively deform both side walls 11 and 12 of the main liquid chamber A.

[0008]

In the above structure, with the bracket 4 formed in a substantially inverted U-shape fixed to the base 5 while covering the outer periphery of the vibration isolating rubber body 1, the vibration isolating rubber body 1 is pressed downward and the side walls 1
1, 12 are compressed and deformed. When the load of the vibrating body 6 is applied to the inner cylinder 2, the vibrating body 6 is displaced downward, and the entire vibration-proof rubber body 1 is further compressed and deformed, and a stopper clearance d1 is generated between the top surface 1a and the bracket top wall 41. .

When vibration is input in this state, the inner cylinder 2 is displaced up and down, but since the top wall 41 of the bracket 4 serves as a stopper to restrict upward displacement, the side walls 11, 12 are formed.
The vertical state of compression is not eliminated, and tensile stress is not generated, so sufficient durability is exhibited.

[0010]

1 and 2, a block-shaped anti-vibration rubber body 1 is held and fixed on a vehicle frame 5, which is a base body, whose outer periphery is held by a substantially inverted U-shaped bracket 4 which opens downward. The bracket 4 is a press-formed product of a metal plate body having reinforcing flanges 42 on both side edges, and both end horizontal portions 43 are fixed to the vehicle frame 5 by bolts. An inner cylinder 2 is embedded in the anti-vibration rubber body 1, and a rod-shaped mounting portion 6 of the engine, which is a vibrating body, is inserted and fixed in the inner cylinder 2.

The antivibration rubber body 1 has a main liquid chamber A which is formed by engraving the inner cylinder penetrating portion in the lower center with a certain depth from the bottom surface and hermetically closing it with a bottom plate 7. An outer peripheral portion of the bottom surface of the vibration-proof rubber body 1 is joined to a ring-shaped throttle member 8 having an inverted U-shaped cross section. The aperture of the throttle member 8 is closed by a bottom plate 7 to form a throttle channel F inside. There is. The central portion of the bottom plate 7 projects upward along the inner circumference of the diaphragm member 8, and the projecting portion 71
A thin rubber film 3 is arranged so as to partition the lower space of the above, and a sub liquid chamber B having this as a chamber wall is formed between it and the lower surface of the protruding portion 71. The sub liquid chamber B and the main liquid chamber A are communicated with each other through a throttle channel F, and the inner cylinder 2 is accompanied by engine vibration.
Is displaced up and down, the enclosed liquid flows into both liquid chambers A and B through the throttle channel F, and a large vibration damping occurs.

A stopper rubber 9 having a similar shape to that of the main liquid chamber A is housed in the main liquid chamber A. When the inner cylinder 2 moves downward due to engine vibration, the upper side wall of the main liquid chamber A contacts the stopper rubber 9. Regulated. Further, the top surface 1 forming the arc surface of the vibration-proof rubber body 1
A stopper clearance d1 is formed between a and the arc-shaped top wall 41 of the bracket 4, and the upward movement of the inner cylinder 2 due to engine vibration is restricted by the contact between the top surface 1a and the top wall 41. .

When the inner cylinder 2 moves upward, the chamber wall of the main liquid chamber A is deformed in the pulling direction. in this case,
Since the chamber walls 11 and 12 formed on the both end surfaces of the vibration-proof rubber body 1 are relatively thin, there is a concern that the durability may deteriorate when the internal pressure of the main liquid chamber A is large. Therefore, even if the inner cylinder 2 is displaced upward, the stopper clearance d1 is set to the chamber wall 1
No. 1 and No. 12 are set so as not to generate tensile stress.

The stopper clearance d1 will be described below.
A structure for realizing the above will be described.

As shown in FIG. 3, the anti-vibration rubber body 1 before being inserted into the bracket 4 has substantially the same cross-sectional shape as the bracket 4, but the height h1 of the top surface 1a forming the arc surface thereof is It is higher than the height h2 of the top wall 41 of the bracket 4, and the curvature of the former is larger than that of the latter. The left and right side surfaces of the anti-vibration rubber body 1 are bulged portions 13 that bulge outward. When the anti-vibration rubber body 1 is inserted into the bracket 4 as shown by the arrow in the figure, the left and right bulged portions 13 are The bracket 4 is pressed against the inner circumferences of both legs to prevent the bracket 4 from falling off.

In a state before fixing the bracket 4 having the anti-vibration rubber body 1 mounted thereon to the vehicle frame 5, as shown in FIG. 4, with respect to the bottom plate 7 located in contact with the vehicle frame 5,
The horizontal portions 43 on both ends of the bracket 4 are located above by d2.
When the bracket 4 is bolted to the vehicle frame 5, the top wall 41 of the bracket 4 pushes the top surface 1a of the vibration isolating rubber body 1 downwardly to deform it in the compression direction as a whole, and the side walls 11, 12 thereof. (FIG. 2) is also in a compressed state.

When the engine is supported by the inner cylinder 2 in this state, the inner cylinder 2 is displaced downward by the static load, and
As shown in FIG. 5, the stopper clearance d1 is generated between the top surface 1a of the anti-vibration rubber body 1 and the top wall 41 of the bracket 4.

Even if the inner cylinder 2 is displaced upward within the range of the stopper clearance d1 due to the input of engine vibration,
The compressed state of the side walls 11 and 12 is not eliminated, and tensile stress does not occur. This ensures sufficient durability.

[0019]

As described above, according to the liquid-filled anti-vibration bush of the present invention, without providing a separate rubber stopper plate,
With a simple and inexpensive structure, sufficient durability can be secured.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a liquid filled vibration damping bush in an engine supporting state showing an embodiment of the present invention, which is a cross sectional view taken along line I-I of FIG.

FIG. 2 is a vertical cross-sectional view of the liquid-filled anti-vibration bush with the engine supported, and is a cross-sectional view taken along the line II-II of FIG.

FIG. 3 is an exploded cross-sectional view of a liquid filled vibration damping bush.

FIG. 4 is a transverse cross-sectional view of the liquid-filled anti-vibration bush before being attached to the vehicle frame.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Anti-vibration rubber body 1a Top surface 11, 12 Side wall 2 Inner cylinder 3 Rubber film (chamber wall) 4 Bracket 41 Top wall 5 Vehicle frame (base body) 6 Rod-shaped mounting part (vibrating body) A Main liquid chamber B Sub liquid chamber F Restricted flow path

Claims (1)

[Claims] 1. A rubber block is provided on a base body to form a vibration-proof rubber body, and an inner cylinder for connecting the vibration body to the vibration-proof rubber body is embedded through, and both ends thereof are provided in a lower half portion of the vibration-proof rubber body. A main liquid chamber having side surfaces on both side walls is formed, and the main liquid chamber is made to communicate with a sub liquid chamber composed of a freely deformable chamber wall through a throttle channel, and the height is higher than that of a vibration-proof rubber body. And a substantially inverted U-shaped bracket that covers the outer circumference of the anti-vibration rubber body, and when the bracket is fixed to the base body, the anti-vibration rubber body is pushed downward by the top wall of the anti-vibration rubber body, so that Liquid-filled anti-vibration bush characterized by compressing and deforming both side walls.