JPS62196433A - Liquid-sealed vibration isolator - Google Patents

Abstract

PURPOSE:To effectively prevent transmission of vibration extending over the wide range of frequency by lowering a spring constant of a device to absorb vibration when high-frequency small-amplitude vibration is input and exhibiting large vibration damping forces when low-frequency large-amplitude vibration is input. CONSTITUTION:The first liquid chamber A is partitioned by a thin rubber elastic substance wall 1 expanding downward, and an upper plate 3 also serving as a stopper element is joined to the upper end opening of the chamber. Both right and left end portions of the upper plate 3 are extended upward to form stopper portions 31, and a stopper rubber member 32 is provided at each bent-up opposite surface. A connecting member 4 substantially T-shaped in section is disposed between both stopper portions 31 and the upper plate 3, and a vibration isolating rubber body 5 having a small spring constant is stretched between both side edges of the connecting member 4 and vertical walls 311 of the stopper portions 31. Further, a cylindrical side plate 6 is joined to the lower end of the rubber elastic substance wall 1. A partition plate 7, a thin rubber substance wall 2 and the outer peripheral edge of a base plate 8 are wrapped and held by the side plate 6, and the liquid chambers A, B communicate with each other through a throttle hole 73.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid-filled vibration isolator, and more particularly to a liquid-filled vibration isolator that can be suitably used as an engine mount for F and F cars.

[Prior Art] A liquid-filled vibration isolator includes a first liquid chamber whose chamber wall is a thick rubber elastic wall that supports a vibrating body, and a first liquid chamber that is separated from the liquid chamber by a partition plate provided with a throttle hole. , a second liquid chamber whose chamber wall is a thin rubber elastic wall that freely deforms depending on the internal pressure is often used, and such a vibration isolator has a sealing liquid in the aperture hole when a large amplitude vibration is input. flows and generates a large vibration damping force.

[Problems to be Solved by the Invention] By the way, since the engine rear mount of the above-mentioned F and F cars requires almost no static load supporting force, the thickness of the above-mentioned thick rubber elastic body can be made thinner; is preferable in that it can absorb high frequency imaging well. However, reducing the thickness of the rubber elastic body results in a decrease in its expansion modulus, resulting in the problem that the vibration damping effect described above is not effectively exerted.

In view of these problems, the present invention is a liquid-filled vibration isolator used for engine mounts that hardly receive shared loads, and which absorbs vibrations by reducing the spring constant of the device sufficiently when high-frequency, small-amplitude vibrations are input. It is an object of the present invention to provide a liquid-filled vibration isolator that can effectively prevent vibration transmission over a wide frequency range by exhibiting a large vibration damping force when a low frequency, large amplitude vibration is manually applied.

[Means for Solving the Problems] The configuration of the present invention will be explained with reference to FIG. The vibration isolator includes a connecting member 4 that is connected to a vibrating body and vibrates integrally with the vibrating body, a bridge 1 to a collar body 3 that are provided at a predetermined distance from the connecting member 4 in the vibration direction, and A first liquid chamber A consisting of a chamber wall 1 that can be deformed in a direction, and a chamber wall 2 that is deformed freely according to internal pressure and is divided from the first liquid chamber Δ by a partition plate 7 provided with a throttle hole 73. The stopper body 3 is coupled to one end of the first liquid chamber Δ in the vibration direction, and the other end of the first liquid chamber A in the vibration direction is 1. Substantially static relative to the vibrating body. It is bonded to the substrate with t=.

"Operations and Effects" When low frequency, large amplitude vibration is applied manually, the connecting member 4 vibrates greatly and comes into contact with the stopper body 3. As a result, the stopper body 3
The chamber wall 1 of the first liquid chamber A coupled with the first liquid chamber A is deformed in the vibration direction, and a high internal pressure is generated in the liquid chamber A, and the sealing liquid flows through the throttle hole 73.

Therefore, large-amplitude vibrations are quickly reduced by the high spring force caused by the internal pressure and the high damping force caused by the flow resistance of the sealing fluid.

The connecting member 4 does not come into contact with the stopper body 3 when high-frequency, small-amplitude vibrations are input. Therefore, even if the connecting member 4 vibrates, this vibration is not transmitted to the base body.

[Example] In FIG. 1, a thick inner rubber elastic wall 1 that expands downward constitutes the chamber wall of a first liquid chamber A, and an upper plate 3 that also serves as a stopper body is joined to its upper end opening. It is. The upper plate 3 has a rectangular shape as shown in FIG. 2, and its upper surface serves as a stopper portion 3a, and its left and right ends are extended upward and then bent inward to meet the stopper surface 3a and a predetermined position. The stopper portions 31 form stopper surfaces 31a facing each other at intervals. Both stopper parts 31 are opposed to each other at a predetermined interval, and a stopper rubber body 32 is provided on the opposing surfaces bent upward.

A connecting member 4 is disposed between the stopper portions 31 and the upper plate 3 with a distance therebetween. The connecting member 4 is a columnar body having a substantially T-shaped cross section with a thick center wall, and has a bolt 41 erected on the upper surface of the central portion thereof to be connected to an engine serving as a vibrating body. Both side edges of the connecting member 4 and each stopper portion 31
A vibration-proof rubber body 5 having a sufficiently small spring constant is stretched between the vertical walls 311, and the connecting member 4 is elastically held by the rubber body 5. The rubber body 5 extends to the lower surface and the upper surface of both sides of the connecting member 4, and the stopper rubber layer 51.
It is 52.

A cylindrical side plate 6 is joined to the lower end of the rubber elastic wall 1. The upper half of the side plate 6 is joined to the rubber elastic wall 1, and the lower half holds the outer peripheral edges of the partition plate 7, the thin rubber elastic wall 2 disposed below the partition plate 7, and the bottom plate 8. There is. The rubber elastic wall 2 is deformable and forms a second liquid chamber B between it and the partition plate 7. The partition plate 7 includes a lower plate 71 fixed to the side plate 6 and an upper plate 72 joined to the upper surface of the lower plate 71.
The throttle hole 73, which communicates with both the liquid chambers A and B, is formed by the control holes provided at radially symmetrical positions and the grooves formed on the joint surfaces of the respective plates 71 and 72 connecting the control holes. has been done.

The bottom plate 8 is formed into a container shape and is fixed to the vehicle frame as a base by a bolt 81 protruding from the center of the bottom surface.

When the vertical vibration of the engine is input, the connecting member 4 moves up and down together with it. At this time, the small amplitude vibration of the engine is effectively absorbed by the vibration isolating rubber body 5 which supports the connecting member 4 and has a sufficiently small spring constant.

On the other hand, when the width vibration is manually applied, the connecting member 4 moves up and down greatly, and the stopper surface 3a of the upper plate 3 or the stopper part 3
1. Along with this, the thick rubber elastic wall 1 integrally joined to the upper plate 3 is deformed, the internal pressure of the liquid chamber A changes, and the sealing liquid flows through the throttle hole 73 at high speed. In this way, the large amplitude vibration is quickly reduced by the high spring force due to the increase in the internal pressure of the liquid chamber A and the high damping force due to the liquid flowing through the throttle hole 73.

In addition, the connecting member 4, the stopper surface 3a, and the stopper part 3
The impact upon contact with the stopper rubber layer 51, 52 is alleviated by the stopper rubber layer 51, 52. In addition, in response to vibration input in the left-right direction in the figure, the side surface of the central part of the connecting member 4 is connected to the stopper rubber body 32.
to suppress vibrations.

The vibration-proof rubber body 5 is not necessarily required. Further, the thick rubber elastic wall 1 can be replaced with a bellows or the like that can be expanded and contracted in the vertical direction.

[Brief explanation of drawings]

FIG. 1 is an overall sectional view of the device, a sectional view taken along line II in FIG. 2, and FIG. 2 is a plan view of the device. 1... Thick rubber elastic wall (chamber wall of the first liquid chamber)
2...Thin rubber elastic wall (chamber wall of second liquid chamber)
3... Upper plate (stopper body) 3a, 31a... Stopper surface 4... Connecting member 5... Vibration isolating rubber body 7...・Partition plate 73... Throttle hole 8... Bottom plate A... First liquid chamber B... Second liquid chamber

Claims (2)

[Claims] (1) A connecting member connected to the vibrating body and vibrating integrally therewith, a stopper body provided at a predetermined distance from the connecting member in the vibration direction, and a chamber wall deformable in the vibration direction. and a second liquid chamber comprising a chamber wall that is partitioned from the first liquid chamber by a partition plate provided with a throttle hole and that freely deforms according to internal pressure, and the stopper A plate is coupled to one end of the first liquid chamber in the vibration direction, and the other end of the first liquid chamber in the vibration direction is coupled to a base that is substantially stationary with respect to the vibrating body. Liquid filled vibration isolator. (2) The chamber wall of the first liquid chamber is composed of a cylindrical thick-walled rubber elastic body provided facing in the vibration direction, and a stopper surface is provided at one end of the rubber elastic body and faces oppositely with the connecting member interposed therebetween. 2. A liquid-filled vibration isolating device according to claim 1, wherein a stopper body having a spring constant is joined to the stopper body, and the connecting member is connected to a portion of the stopper body between the stopper surfaces by a vibration isolating rubber body having a small spring constant.