JPS6246041A - Vibration-isolator - Google Patents

Abstract

PURPOSE:To suitably absorb vibration by providing an orifice separately from a shaft piercing through a liquid chamber, thereby to always ensure movement of a fluid. CONSTITUTION:The middle portion of a connecting shaft 26 pierces through an intermediate film 24, and a ring 28 is fixed to the intermediate film 24 to move in the axial direction in relative to the outer periphery of the connecting shaft 26. Therefore, the ring 28 corresponds to the outer periphery of the connecting shaft 26, so that the intermediate film 24 moves relatively to the connecting shaft 26. Accordingly, even if the connecting shaft 26 moves, the intermediate film 24 is kept from being pulled to move by the connecting shaft 26, so that the expansion and contraction of an upper small liquid chamber 22A and a lower small liquid chamber 22B are ensured to suitably absorb vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibration isolating device that is interposed between a vibration generator and a vibration receiver and absorbs vibrations by the resistance force of a liquid passing through an orifice.

[Background technology and issues to be solved] As a vibration isolating device used in automobile engine mounts, cab mounts, potty mounts, etc., a liquid chamber is partitioned with an intermediate film, and an orifice provided in this partition part is used to reduce resistance during liquid flow. A vibration isolating device has been proposed that causes the
No. 7704).

This vibration isolator is provided with a shaft that passes through the partition wall in order to transmit the expansion/contraction force of one liquid chamber as the expansion/contraction force of the other liquid chamber and to produce a greater damping effect. An orifice is formed between this shaft and the partition wall, through which liquid rapidly passes when the liquid chamber expands or contracts.

However, in this vibration isolator, when vibration acts in a direction that is misaligned with the axis of the penetrating shaft, the distance between the shaft and the partition wall, that is, the size of the orifice changes, and damping cannot be obtained at a specified frequency ψ. There will be no.

In consideration of the above facts, the present invention provides a vibration isolating device that absorbs vibration by combining a liquid chamber and an orifice.
The object is to obtain a vibration isolator that can reliably absorb vibrations even from different directions.

[Summary and operation of the invention] In the vibration isolating device according to the present invention, a liquid chamber is divided into small liquid chambers through an intermediate membrane and communicated with each other through an orifice, and the intermediate membrane receives vibrations from one small liquid chamber and the other small liquid chamber. It is characterized in that it has a shaft passing through it that transmits information to the chamber, and that this shaft can slide on the interlayer membrane.

Therefore, in the present invention, the orifice provided separately from the shaft that penetrates the liquid chamber always ensures fluid movement, and even when vibrations in a direction different from the axial direction act, the shaft does not move relative to the intermediate film. , it is possible to ensure the expansion and contraction of the liquid chamber and to ensure the generation of resistance at the orifice to perform appropriate vibration absorption.

Embodiment 1 of the Invention FIG. 1 shows an embodiment of a vibration isolator to which the present invention is applied. This vibration isolator IO has a base plate 12 provided in the middle part for attachment to the vehicle body, and has attachment holes 14 drilled near the outer periphery to which attachment bolts are applied.

This base plate 12 has a through hole in the center, and an elastic body 16 such as rubber is vulcanized and bonded to the vicinity of the inner circumference. This elastic body 16 extends above and below the base plate 12,
A ring plate 17 is vulcanized and bonded to the upper extension portion.
This ring plate 17 has a hair tuft plate 18 fixed by caulking, and a ring plate 19 is vulcanized and bonded to the downwardly extending portion.
The elastic body 16 to which is fixed by caulking forms a liquid chamber 22 together with the upper brake 1B and the lower plate 20, and this liquid chamber 22 is connected to the -L small liquid chamber 22A and the lower liquid chamber 22B by an intermediate film 24. It is divided into. The outer peripheral portion of the intermediate film 24 is integrally connected to the elastic body 16.

A connecting shaft 26 passes through the upper plate 18 and the lower plate 20 at their axial center portions. The upper end of this connecting shaft 26 is fixed to the upper plate 18, and the lower end is fixed to the lower plate 20.
An O-ring 25 is attached between the sleeve 20A and a watertight structure.

The connecting shaft 26 has a cylindrical shape, and a mounting bolt (not shown) passes through the connecting shaft 26 so that an automobile engine can be mounted and fixed on the upper plate 18.

The intermediate portion of the connecting shaft 26 passes through the intermediate film 24, and a ring 28 is fixed to the intermediate film 24 so as to be movable relative to the outer circumference of the connecting shaft 26 in the axial direction. This ring 28 can be made of nylon, aluminum, iron, etc., and the gap between it and the outer periphery of the connecting shaft 26 is about 0.1 to 0.3 m.

A small cylinder 30 is fixed through the intermediate film 24, and an orifice 32 is formed inside the upper liquid chamber 22A and the lower liquid chamber 22B.
It communicates with

Next, the operation of this embodiment will be explained.

The base plate 12 is fixed to the body of an automobile (not shown) using the mounting holes 14. Further, an automobile engine (not shown) is mounted on the upper plate 18, and is fixed to the upper plate 18 by bolts inserted into the connecting shaft 26.

When the engine is in operation, engine vibrations are transmitted through the upper plate 18 and are also transmitted to the lower plate 20. The elastic body 16 that receives this vibration absorbs the vibration due to internal friction. Furthermore, as the liquid moves through the orifice 32 by expanding and contracting the small liquid chamber 22A and the lower liquid chamber 22B, vibrations are absorbed by the resistance force generated during this movement.

The relationship between the -L small liquid chamber 22A and the lower liquid chamber 22B is such that when the connecting shaft 26 moves downward and the upper liquid chamber 22A is reduced, the lower plate 20 of the lower liquid chamber 22B moves downward. Since the liquid chamber is expanded and the movement of fluid passing through the orifice 32 is promoted, a larger resistance force is generated than when the liquid chamber is expanded or contracted in width. The same holds true when the connecting shaft 26 moves in the negative direction.

In particular, since a ring 28 corresponds to the outer periphery of the connecting shaft 26 so that the interlayer film 24 can move relative to the connecting shaft 26, even when the connecting shaft 26 moves downward in FIG.
The intermediate film 24 is not moved by being pulled by the connecting shaft 26, and ensures the expansion and contraction operations of the upper liquid chamber 22A and the lower liquid chamber 22B.

Furthermore, even when vibrations from the engine act in a direction different from the axial direction of the connecting shaft 26, the connecting shaft 26 moves relative to the intermediate film 24 to expand and contract the small liquid chamber 22A and the lower liquid chamber 22B. . Also in this case, since the orifice 32 always has the same inner diameter, the size of the orifice 32 does not change when the connecting shaft 26 moves, and stable attenuation can be obtained at the target frequency.

[Effects of the Invention] As described above, in the vibration isolating device according to the present invention, the liquid chamber is divided into small liquid chambers through the intermediate membrane and communicated with each other through the orifice, and the intermediate membrane is not subjected to vibration. The shaft that transmits the signal to the other small liquid chamber passes through it, and this shaft is characterized by being able to slide on the interlayer film, so even if the vibration acts in a direction different from the predetermined direction, the desired frequency can be maintained. It has an excellent effect of achieving reliable vibration damping.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of a vibration isolator according to the present invention. DESCRIPTION OF SYMBOLS 10... Vibration isolator, 16... Fist elastic body, 18... Upper plate, 20... Fist lower plate, 22A... Upper fluid chamber, 22B... Lower fluid chamber, 24... Intermediate film , 26... Connection shaft, 28... Ring, 32... Orifice.

Claims (2)

[Claims] (1) The liquid chamber is divided into small liquid chambers through an intermediate membrane and communicated through an orifice, and a shaft passes through the intermediate membrane to transmit vibrations to the other small liquid chamber. A vibration isolator characterized by being able to slide with an interlayer film. (2) The vibration isolator according to claim 1, wherein the orifice is formed through an intermediate film.