JPH04102741A - Liquid-sealed vibrationproof bush - Google Patents

Abstract

PURPOSE:To drastically prolong service life by forming a stopper rubber layer which is separated from a vibrationproof rubber body, on the outer peripheral part of an inner cylinder which contacts a stopper body for regulating the shift by the attachment the of inner cylinder when vibration is inputted. CONSTITUTION:A thin stopper rubber layer 5 having a certain thickness is formed separately from a vibrationproof rubber body 3 on the upper surface at the center of the outer periphery of an inner cylinder 2. Though the vibrationproof rubber body 3 uses a rubber material having the superior vibrationproofness, the stopper rubber layer 5 uses the rubber material having the superior impact resistance. When the inner cylinder 2 contacts a stopper body 4, the generation of abnormal noise is effectively prevented by the stopper rubber layer 5, and the generation of a crack on the stopper rubber layer 5 is prevented because of the superior impact resistance. Further, even if a crack is generated, the propagation of the crack to the vibrationproof rubber body 3 is prevented, because the stopper rubber layer 5 is formed separately from the vibrationproof body 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a liquid-filled anti-vibration bushing, and more particularly to structural improvements thereof.

[Prior Art] A vibration-proof bushing has a vibration-proof rubber body bonded between an inner cylinder and an outer cylinder, and because of its compact shape, it is often used in vehicle engine mounts and the like. In recent years, there have been some anti-vibration bushings in which a liquid chamber is provided inside the anti-vibration rubber body to effectively damp vibration through the action of a sealing liquid.
As shown in FIG.

In the figure, an interring 6 is press-fitted into a large-diameter, thin-walled outer cylinder 1 along its inner periphery, and the interring 6 is open at the center of its upper circumferential surface. The vibration isolating rubber body 3 is formed by joining the outer periphery to the inner circumference of the upper half of the interring 6, and the inner cylinder 2 is embedded through the center of the bottom wall of the vibration isolating rubber body 3.

A recess communicating with the opening of the interring 6 is formed in the vibration isolating rubber body 3, leaving side walls at both ends to form a main liquid chamber A. The interring 6 has a concave center on its upper half circumference, and an arc-shaped throttle member 7 in which a folded throttle channel 71 is formed.
is arranged. The lower circumferential surface of the interring 6 is further greatly recessed inward, and a thin rubber sheet 8 is disposed here to constitute a sub-liquid chamber B, and the throttle channel 71 is connected to the sub-liquid chamber B and the main liquid chamber. It is connected to A.

A rubber stopper plate 9 having a constant thickness is disposed between the bottom surface of the vibration isolating rubber body 3 and the concave portion of the interring 6 to restrict the amount of downward movement of the inner cylinder 2 due to vibration input.

Furthermore, a stopper body 4 made of resin and having a similar shape that is slightly smaller than the shape of the liquid chamber is inserted in the main liquid chamber A to regulate the amount of upward movement of the inner cylinder 2 due to vibration input. .

[Problems to be Solved by the Invention] Incidentally, on the outer periphery of the center portion of the inner cylinder 2 that abuts the stopper body 4, a thin stopper rubber layer 31 is provided with a vibration-proofing rubber body in order to prevent abnormal noises from occurring when abutting the stopper body 4. Although it extends more integrally than 3,
Due to the thin wall, cracks may occur due to the impact of contact.
There is a problem in that this crack propagates to the vibration-proof rubber body 3 and shortens the life of the vibration-proof bushing.

In this case, the generation of cracks can be prevented by making the stopper rubber layer 31 thicker, but this will cause the deformation of the stopper rubber layer 31 during contact to extend to the vibration isolating rubber body 3, causing a change in its characteristics. This will cause problems.

The present invention solves these conventional problems, and it is possible to improve the strength of the stopper rubber layer, and also to prevent cracks that occur in the stopper rubber layer from extending to the vibration-proof rubber body, resulting in a long-life liquid encapsulation system. The purpose is to provide an anti-vibration bushing.

[Means for Solving the Problems] To explain the present invention in detail, a vibration-proof rubber body 3 is bonded and disposed between an outer cylinder 1 and an inner cylinder 2, and a liquid chamber A is provided in the vibration-proof rubber body 3. In the liquid-filled anti-vibration bushing, a stopper body 4 is inserted into the liquid chamber A to bring the inner cylinder 2 into contact with the inner cylinder 2 during vibration input to restrict further displacement. A stopper rubber layer 5 separate from the vibration isolating rubber body 3 is formed on the outer circumference of the inner cylinder 2 in contact with the inner cylinder 2.

[Function] According to the liquid-filled anti-vibration bushing having the above structure, the stopper rubber layer 5 on the outer periphery of the inner cylinder 2 is formed separately from the anti-vibration rubber body 3. It can be made of a rubber material with excellent impact resistance that is different from the rubber material of the vibration isolating rubber body. Even if a crack occurs in the stopper rubber layer 5, it will not propagate to the separate vibration isolating rubber body 3.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 and 2, focusing on the differences from the conventional example.

In the figure, an interring 6 is press-fitted into a thin outer cylinder 1, and a main liquid chamber A is formed within a vibration isolating rubber body 3 that is bonded and disposed within the interring 6. This main liquid chamber A communicates through a throttle channel 71 in the throttle member 7 to a sub-liquid chamber B whose chamber walls are made of a thin rubber sheet 8.

A stopper body 4 made of resin is inserted in the main liquid chamber A, and the stopper body 4 is configured to stop the main liquid when the inner cylinder 2 under a static load is displaced slightly upward than shown in the figure. It has a similar shape to the shape of room A. When vibration is input, the inner cylinder 2 is displaced up and down, and when displaced upward, the upper surface of the center of its outer periphery comes into contact with the lower surface of the stopper body 4. When a large vibration is input, the stopper body 4 is pushed by the inner cylinder 2 and moves until its outer periphery abuts the inner periphery of the throttle member 7, and in this state, the movement of the inner cylinder 2 that abuts the stopper body 4 is restricted. be done.

Here, a thin stopper rubber layer 5 having a constant thickness is formed on the upper surface of the center of the outer circumference of the inner cylinder 2, separate from the vibration-proof rubber body 3. The stopper rubber layer 5 is made of a rubber material with excellent impact resistance, whereas the vibration isolating rubber body 3 uses a rubber material with excellent vibration damping performance.

Therefore, when the inner cylinder 2 comes into contact with the stopper body 4, the occurrence of abnormal noise is effectively prevented by the stopper rubber layer 5, and the stopper rubber layer 5, which has excellent impact resistance, cracks. Never.

Furthermore, even if a crack occurs, the crack will not propagate to the vibration-isolating rubber body 3 because it is molded separately from the vibration-isolating rubber body 3.

Note that the stopper rubber layer 5 only needs to be substantially separated from the vibration-isolating rubber body 3, so that a part of the rubber material flows during molding of the vibration-isolating rubber body to form the stopper rubber layer. By providing multiple relatively narrow rubber passages,
In addition to molding the stopper rubber layer and the vibration-proof rubber body at the same time,
It may also be possible to prevent only the propagation of cracks.

[Effects of the Invention] As described above, according to the liquid-filled anti-vibration bushing of the present invention, it is possible to effectively prevent the generation of cracks in the stopper rubber layer that prevents the generation of abnormal noise and the propagation of the cracks to the anti-vibration rubber body. is possible,
This makes it possible to significantly extend the lifespan.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, in which FIG. 1 is an overall vertical cross-sectional view of a liquid-filled anti-vibration bushing, FIG. 2 is an overall cross-sectional view thereof, and FIGS. 3 and 4 are A conventional example is shown, and the third
The figure is an overall longitudinal sectional view of the liquid-filled anti-vibration bushing, and FIG. 4 is an overall cross-sectional view thereof. 1...Outer cylinder 2...Inner cylinder 3...Vibration-proof rubber body 4...Stopper body 5...Stopper rubber layer 6...Interring 7...Aperture member 71...Aperture Channel 8...Rubber sheet 9...Rubber stopper plate A...Main liquid chamber (liquid chamber) B...Sub-liquid chamber Fig. 3 Fig. 4

Claims (1)

[Claims] A vibration-proof rubber body is bonded and arranged between the outer cylinder and the inner cylinder, and
In the liquid-filled vibration isolating bushing having a liquid chamber formed in the vibration isolating rubber body, a stopper body is inserted into the liquid chamber to abut the inner cylinder to restrict further displacement when vibration is input, and a stopper body is inserted into the liquid chamber to prevent further displacement. On the outer periphery of the inner cylinder that comes into contact with the body,
A liquid-filled anti-vibration bushing characterized in that a stopper rubber layer is formed separately from the above-mentioned anti-vibration rubber body.