JPS61262244A - Vibration absorbing device - Google Patents

Abstract

PURPOSE:To enable the absorption of vibration from different directions, by the method wherein means, resisting to fluid movement occurring due to vibration exerted in an axial and a radial direction, are mounted to an axial vibration absorbing liquid chamber and a radial vibration absorbing liquid chamber. CONSTITUTION:A space an upper vibration absorbing means 58, attached to the inner periphery of the upper part of an upper cylinder body 12, and a diaphragm 24 forms a lower vibration absorbing means 30, and in the lower vibration absorbing means 30, a liquid chamber, formed by filling a space between the upper vibration absorbing mans 28 and the diaphragm 24 with liquid, is partitioned into an upper liquid chamber 34 and a lower liquid chamber 36 by means of a partition 32. The two chambers 34 and 36 are intercoupled through an orifice 42. A vibration absorbing main body 50 of the rectangular window 56 part bored in an inner cylinder 48 pressed in an upper cylinder body 12 forms a notch 58 to form first and second liquid chambers 60 and 61 between the vibration absorbing main body and the inner periphery of the upper cylinder body 12. The two chambers 60 and 62 are intercommunicated through an orifice 66 formed between the fine groove in the outer periphery of the inner cylinder 48 and the inner periphery of the upper cylinder body 12.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vibration isolator that absorbs vibrations from a vibration source.
In particular, the present invention relates to a vibration isolator that can absorb vibrations from different directions.

[Background technology and matters to be solved]

2. Description of the Related Art Vibration isolators having rubber that expands and contracts due to vibrations from vibration sources are used in cab mounts, body mounts, engine mounts, etc. of vehicles. In this vibration isolator, vibrations are absorbed by internal friction that occurs during vibrations.

In order to effectively absorb vibrations, a liquid chamber is provided that expands and contracts in response to vibrations, and the liquid in this chamber passes through the resistance generating means as the liquid chamber expands and contracts, thereby effectively absorbing vibrations. Devices have also been proposed.

However, these vibration isolators do not take into consideration the absorption of vibrations in different directions, so it is impossible to effectively absorb vibrations depending on the direction of vibration.

The present invention takes the above-mentioned facts into account and aims to provide a vibration isolator that can absorb vibrations from different directions.

[Summary and operation of the invention]

The vibration isolator according to the present invention includes an axial vibration-absorbing liquid chamber and a radial vibration-absorbing liquid chamber, and each of these liquid chambers is provided with means for resisting liquid movement caused by vibrations acting in the axial and radial directions. It is provided.

Therefore, due to the vibrations acting in the axial and radial directions, the liquid in each liquid chamber is given resistance when moving due to the vibrations, so that the vibrations can be effectively absorbed.

[Embodiments of the invention]

FIG. 1.2 shows a vibration isolating device 10 according to a first embodiment of the present invention.
It is shown. This vibration isolator 10 has a flange 14 fixed to the outer periphery of an upper cylindrical body 12 disposed in the center, and is attached to a vehicle body (not shown) using a circular hole 16 formed in the flange 14.

The lower end of the upper cylinder 12 is a radially bent flange 18, which is caulked and fixed to a flange 22 formed at the upper end of the upper cylinder 20.

A rubber diaphragm 24 is located between the flange portions 18 and 22.
The outer periphery of the diaphragm 24 and the upper cylinder body 2 are held together.
An air chamber 26 is formed between the bottom of the 0 and the bottom.

An upper vibration absorbing means 28 is provided on the upper inner periphery of the upper cylinder 12, and a lower vibration absorbing means 30 is provided between the upper vibration absorbing means 28 and the diaphragm 24.

In the lower vibration absorbing means 30, the upper vibration absorbing means 28 and the diaphragm 24
A liquid is filled between them to form a liquid chamber, and this liquid chamber is divided by a partition plate 32 into an upper liquid chamber 34 and an upper liquid chamber 36.

The partition plate 32 has a cylindrical portion 32A whose outer circumferential portion is bent at right angles, and the lower end of this cylindrical portion 32A is a tapered portion 32B whose outer diameter is gradually increased.
The tip of B is a flange portion 32C bent in the radial direction. This flange portion 32G is the diaphragm 24
It is also held between the upper cylinder body 12 and the upper cylinder body 20.

As shown in FIG. 3, an abutting plate 38 is fixed to the partition plate 32 from below. The abutment plate 38 has an outer end welded to the cylindrical portion 32A and an inner end welded to the vicinity of the center of the partition wall plate 32, and has an L-shaped longitudinal cross section and a C-shaped planar shape between these. A groove 40 is formed, and the partition plate 3
An orifice 42 is formed between the contact plate 38 and the contact plate 38. This orifice 42 communicates with the upper liquid chamber 36 through a circular hole 44 formed in one end of the groove 40, and the other end communicates with the upper liquid chamber 34 through a circular hole 46 formed in the partition plate 32. ing.

Therefore, the upper liquid chamber 34 and the upper liquid chamber 36 are communicated with each other via the orifice 42, so that the liquid can move between them.

The upper vibration absorbing means 28 includes a cylindrical vibration absorbing main body 50 that is vulcanized and bonded into the inner cylinder 48 . This vibration absorbing main body 50 is generally made of rubber, and the outer periphery of a main shaft 52 is vulcanized and bonded to the central portion.

The upper end of the main shaft 52 protrudes from the vibration absorbing main body 50 and serves as a mounting bolt portion 54, which is used for mounting an engine (not shown).

By press-fitting the inner cylinder 48 into the upper cylinder body 12, the vibration absorbing main body 50 is supported by the upper cylinder body 12 via the inner cylinder 48, so that when the mounting bolt part 54 moves up and down due to engine vibration, The vibration absorbing main body 50 absorbs engine vibrations due to internal friction, and the upper liquid chamber 34 is expanded and contracted by the deformation of the vibration absorbing main body 50, and the liquid in the upper liquid chamber 34 and the upper liquid chamber 36 flows into the orifice 42. Vibrations in the axial direction of the main shaft 52 are absorbed.

A rectangular window 56 is bored in each of the inner cylinders 48 on the opposite side with the main shaft 52 in between. 1st
A liquid chamber 6o and a second liquid chamber 62 are formed. A narrow groove is formed on the outer periphery of the inner cylinder 48 between the pair of rectangular windows 56, and an orifice 66 is thereby provided between the narrow groove 64 and the inner periphery of the upper cylinder body 12. This orifice 6
6 is the first liquid chamber 60. The second liquid chambers 62 are communicated with each other, and the liquids sealed in these liquid chambers can be moved with respect to each other.

Therefore, when the main shaft 52 moves in the radial direction due to vibrations from the engine, one of the liquid chambers receives a compressive force, so that the liquid in these liquid chambers mutually moves through the orifice 66. .

Next, the operation of this embodiment will be explained.

The assembly is completed by fixing the vibration isolating device 1o to the vehicle body using the inner cylinder 48 and mounting an engine (not shown) to the mounting bolt portion 54.

The vertical vibration of the engine, that is, the axial vibration of the main shaft 52, is absorbed by the internal friction generated within the vibration absorbing main body 50, but the upper liquid chamber 34 expands and contracts due to the vertical movement of the vibration absorbing main body 50. The liquid between the upper liquid chamber 36 and the upper liquid chamber 36 passes through the orifice 42 and repeatedly circulates with the upper liquid chamber 36. Therefore, vibrations are absorbed by the resistance force generated when the liquid passes through the orifice 42. In particular, since the upper liquid chamber 34 and the upper liquid chamber 36 are communicated with each other through an orifice 42 having a long shaft dimension, they have a large vibration absorbing power.

Further, when the engine moves in the left-right direction, that is, in the radial direction of the main shaft 52, the first liquid chamber 60. As the second liquid chamber 62 expands and contracts, these liquids flow with each other through the orifice 66, and the resulting resistance absorbs vibrations.

Since this orifice 66 is also formed with a long shaft dimension, it has a large vibration absorbing power.

In order to make the vibration absorbing power of the orifice 66 even thicker, the narrow groove 64 can be formed not just on a straight line but in a curved manner.

By setting the ratio of the length to the cross-sectional area of these orifices 42.66 to 6 to 20 times, it is possible to obtain about twice the attenuation of the conventional one.

FIG. 5(A) shows an embodiment in which the upper vibration absorbing means 28 is attached to the upper cylinder body 12. That is, by fitting the ring 70 into the ring groove 68 formed on the outer periphery of the inner cylinder 48 and then press-fitting the inner cylinder 48 into the upper cylinder body 12, the inner cylinder 48 is securely attached to the upper cylinder body 12, and the first liquid chamber 6
0. This allows the second liquid chamber 62 to be sealed.

In addition, in the mounting means shown in FIG. 5(B), a protruding portion 72 extending a part of the vibration absorbing body 5° to the outer periphery of the inner cylinder 48 is provided instead of an O-ring. Since this protruding portion 72 receives a large compressive force when the inner cylinder 48 is press-fitted into the upper cylinder body 12, the space between the inner cylinder 48 and the upper cylinder body 12 can be tightly sealed.

Next, FIG. 6 shows a vibration isolating device according to a second embodiment of the present invention. In this embodiment, especially the assembly.

The upper cylinder body 12 is divided into upper and lower halves,
Coaxially fitted together in a telescopic state and welded 74
is fixed by. After the upper vibration absorber stage 28 is inserted into the liquid in the state shown in FIG.
A, the attachment of the inner cylinder 48 is strengthened.

Next, FIG. 7 shows a third embodiment of the present invention. In this embodiment, a small diameter shaft 76 is extended from the lower end of the main shaft 52 and projects into the upper liquid chamber 34, and a movable plate 80 is attached to a ring groove 78 formed in this small diameter shaft 76 and moves integrally. It is a structure.

The area of the gap between the movable plate 80 and the upper cylinder body 12 is larger than the cross-sectional area of the orifice 42.

Therefore, in this embodiment, the liquid between the movable plate 80 and the upper cylinder 12 resonates at high frequency and small amplitude following the clogging of the orifice 42, and the movable spring is further lowered to obtain a low dynamic multiplier. It has become.

FIG. 8 shows a vibration isolator according to a fourth embodiment of the present invention. In this embodiment, a circular hole 82 is provided in the center of the partition plate 32.
A movable plate 84 is attached to this circular hole 82. This movable plate 84 has enlarged diameter portions 86.88 that protrude in the radial direction at both upper and lower ends of the partition wall plate 32, and the width dimension between these enlarged diameter portions 86.88 is the width dimension of the partition wall plate 32. The movable plate 84 can vibrate in the axial direction.

Therefore, in this embodiment, the movable +!
84 moves up and down, and the upper liquid chamber 34. By making it possible to change the volume of the lower liquid chamber 36, the movement spring is prevented from rising, and a low movement magnification (Kdloo
/KS# 1.5).

Next, FIG. 9 shows a vibration isolator according to a fifth embodiment of the present invention. This embodiment shows a lower vibration absorbing means 90 having a structure significantly different from the lower vibration absorbing means 30 of each of the previous embodiments.

In this lower vibration absorbing means 90, the lower end portion of the support tube 92 is formed into a radially extending flange portion 94, which is clamped and fixed between the upper tube body 12 and the upper tube body 20. An O-ring 96 is attached to the outer periphery of this flange portion 94.

A rubber diaphragm 98 is stretched inside the support tube 92 to form an air chamber 1oo between it and the vibration absorbing main body 50, and a liquid chamber 102 between it and the upper cylinder body 20.

A small diameter shaft 104 projects from the lower end of the main shaft 52, passes through the diaphragm 98, and is fixed to the diaphragm 98. Therefore, the lower end of this small diameter shaft 104 is connected to the liquid chamber 102.
A stopper 106 is coaxially screwed into the tip end.

A stopper 108 having a larger diameter than the stopper 106 is sandwiched between the stopper 106 and the tip of the small diameter shaft 104, and corresponds to a large diameter stopper 110 formed at the lower end of the stopper 106. The movable plate 112 whose hole is inserted into the outer periphery of the stopper 106 has a wall thickness equal to that of the stopper 10.
8 and 110, so as to be able to vibrate in the axial direction.

Therefore, in this embodiment, when the main shaft 52 vibrates in the vertical direction, the liquid in the liquid chamber 102 passes through the gap between the outer periphery of the movable plate 112 and the inner periphery of the upper cylinder 20. vibration damping.

Furthermore, during small-amplitude, high-frequency vibrations, the movable plate 112 vibrates between the stoppers 108 and 110, thereby preventing an increase in the dynamic spring constant. The air chamber 100 is designed to prevent pressure rise in the liquid chamber 102 when a static load is applied to the main shaft 52.

〔Effect of the invention〕

As explained above, since the vibration isolating device according to the present invention includes the axial vibration absorption liquid chamber and the radial vibration absorption liquid chamber, it has an excellent effect of being able to reliably absorb vibrations in different directions. have

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view (corresponding to the section taken along the line 1-1 in FIG. 2.4) showing a first embodiment of the vibration isolator according to the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. The figure is an exploded perspective view of the first embodiment;
The figure is a sectional view taken along line IV-IV in Fig. 3, Fig. 5 is a sectional view showing the state when the inner cylinder is attached to the upper cylinder, and Figs. 6 to 9
The figures are cross-sectional views corresponding to FIG. 1 showing second to fifth embodiments of the present invention, respectively. 10... Vibration isolator, 28... Upper vibration absorbing means, 30... Lower vibration absorbing means, 34... Upper liquid chamber, 36... Upper liquid chamber, 42... Orifice, 48... Inner cylinder, 50... Vibration absorbing main body, 52... Main shaft, 54... Mounting bolt part, 60... First liquid chamber, 62... Second liquid chamber, 66... Orifice, 90... ... lower vibration absorbing means, 98 ... diaphragm, 100 ... air chamber, 102 ... liquid chamber.

Claims (1)

[Claims] (1) A vibration isolator that absorbs and damps vibrations from a vibration source, and includes an axial vibration-absorbing liquid chamber and a radial vibration-absorbing liquid chamber, and these liquid chambers absorb and damp vibrations acting in the axial and radial directions, respectively. A vibration isolating device characterized in that it is provided with means for resisting liquid movement caused by.