JPH0565936A - Vibration control equipment - Google Patents

Abstract

PURPOSE:To improve the durability of a diaphragm and obtain a sufficient loss factor by disposing only a main liquid chamber and a first auxiliary liquid chamber on one side of an inner cylinder so as to provide the first auxiliary liquid chamber with large capacity, thereby preventing the generation of excessive tension to the diaphragm during large amplitude vibration. CONSTITUTION:An inner cylinder 26 is provided in an outer cylinder 16, and a main liquid chamber 42 is disposed on one side of the inner cylinder 26. A first auxiliary liquid chamber 44 is disposed on the opposite side of the main liquid chamber to the inner cylinder 26 side through a partition plate 40. The partition wall of the first auxiliary liquid chamber 44 is partially formed of a diaphragm 22. A second auxiliary liquid chamber 58 is provided on the opposite side to the main liquid chamber 42 with the inner cylinder 26 placed in between. On one side of the inner cylinder 26, only the main liquid chamber 42 and first auxiliary liquid chamber 44 are disposed, so that the first auxiliary liquid chamber 44 can be provided with large capacity, and in association with this, the diaphragm 22 can be provided with large area. This results in improving the durability of the diaphragm 22 and obtaining a sufficient loss factor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-filled type vibration damping device which is used for engine mounts, roll stoppers, bushes and the like of vehicles and absorbs and dampens vibrations from vibration generating parts.

[0002]

2. Description of the Related Art An engine of a car is provided with an anti-vibration device as an engine mount between the engine and the vehicle body.
The engine vibration is prevented from being transmitted to the vehicle body. Vibrations generated in the engine include so-called shake vibration that occurs when the vehicle is traveling at a speed of approximately 70 km / h, so-called idle vibration that occurs when the vehicle is idling, and when the vehicle is traveling at a speed of approximately 5 km / h. .. Generally, the shake vibration has a frequency of less than 15 Hz, while the idle vibration has a frequency of 20 to 40 Hz.
The shake vibration and the idle vibration have different frequencies.

A liquid-filled type prevention device has been proposed as a vibration isolation device that effectively absorbs vibrations of such a wide frequency (Japanese Patent Application Laid-Open Nos. 2-42226 and 4-422).
No. 27).

This vibration isolator comprises an outer cylinder and an inner cylinder, and a main liquid chamber, a first sub-liquid chamber and a second sub-liquid chamber are arranged in layers on one side of the inner cylinder. Here, the main liquid chamber and the first sub liquid chamber are connected by a limiting passage for absorbing shake vibrations, and the main liquid chamber and the second sub liquid chamber are connected by a limiting passage for absorbing idle vibrations. .. Further, part of the partition walls of the first sub liquid chamber and the second sub liquid chamber is composed of a diaphragm, respectively, and can be expanded and contracted. In this vibration isolator, an engine that is a vibration generating portion is connected to one of an inner cylinder and an outer cylinder, and a vehicle body that is a vibration receiving portion is connected to the other of the inner cylinder and the outer cylinder.

During the shake vibration, the liquid moves back and forth between the main liquid chamber and the first sub liquid chamber through the restriction passage for absorbing the shake vibration. However, the shake vibration has a very large amplitude (for example, the amplitude is ± 1 m, unlike the vibration having a high frequency and a small amplitude (for example, the idle vibration has an amplitude of about ± 0.1 mm) such as the idle vibration.
m), the volume of liquid flowing in and out of the first sub-liquid chamber is large.

However, in this vibration isolator, since the liquid chambers are concentrated on one side of the inner cylinder, there is a limit in securing the area of the diaphragm, and the area of the diaphragm is relatively small. Is becoming

Therefore, when a large amount of liquid flows between the main liquid chamber and the first sub liquid chamber due to the shake vibration, the first liquid
Since the diaphragm in the sub liquid chamber is greatly expanded and contracted and a large tension is applied to the diaphragm, the durability of the vulcanized adhesive portion of the diaphragm and the diaphragm itself becomes a problem. Further, when tension is generated in the diaphragm, this tension acts in the direction of blocking the flow of liquid and limits the amount of liquid that passes through the restriction passage. Therefore, it is possible that a sufficient loss coefficient cannot be obtained.

[0008]

In consideration of the above facts, the present invention improves the durability of the diaphragm by preventing excessive tension from being generated in the diaphragm at the time of large-amplitude vibration, and effectively prevents the liquid from flowing in the restricted passage. It is an object of the present invention to obtain an anti-vibration device that can be made to flow into the interior of the device to generate a sufficient loss coefficient.

[0009]

A vibration isolator according to the present invention comprises an outer cylinder connected to one of a vibration generator and a vibration receiver, and an inner cylinder connected to the other of the vibration generator and the vibration receiver. An elastic body provided between the outer cylinder and the inner cylinder, an intermediate cylinder provided between the outer cylinder and the inner cylinder via the elastic body, and an elastic body. A first concave portion which is provided and whose wall surface is deformed when vibration is generated; a partition member which closes the first concave portion; a main liquid chamber which is constituted by the first concave portion and the partition member; A diaphragm provided on the side opposite to the first recess side and covering the partition member, a first sub-liquid chamber constituted by the diaphragm and the partition member, and the first sub-liquid sandwiching the inner cylinder. Restricting passage forming member provided on the opposite side of the chamber, the inner cylinder and the limiting passage structure A second sub liquid chamber provided between the main material chamber, the first sub liquid chamber, and the second sub liquid chamber, the second sub liquid chamber being provided between the first sub liquid chamber and the second sub liquid chamber. It is characterized by

[0010]

In the present invention having the above-described structure, for example, when the inner cylinder is connected to the vibration generating portion such as the engine and the outer cylinder is connected to the vibration receiving portion such as the vehicle body, the vibration from the vibration generating portion causes the inner cylinder, the elastic body, and the The vibration is absorbed by the resistance due to the internal friction of the elastic body supported by the vibration receiving portion through the outer cylinder, and the liquid passage resistance and the liquid column generated in the limiting passage between the main liquid chamber and the sub liquid chamber. Vibration is absorbed by resonance.

When the vibration has a low-frequency and large-amplitude, the liquid travels back and forth between the main liquid chamber and the first auxiliary liquid chamber through the low-frequency and large-amplitude limiting passage, and passes through this limiting passage. The low-frequency large-amplitude vibration is absorbed by receiving resistance or resonating in the liquid column.

On the other hand, when the frequency of vibration rises, the restriction passage for low frequency and large amplitude becomes clogged, so that the liquid passes through the restriction passage for high frequency and the main liquid chamber and the second auxiliary liquid chamber As the liquid column resonates in this restricted passage as it travels back and forth, the dynamic spring constant of the vibration isolator decreases, and high frequency vibrations are absorbed.

Further, in the vibration isolator of the present invention, since only the main liquid chamber and the first sub liquid chamber are arranged in one of the inner cylinders,
The first sub-liquid chamber can have a large volume, and there is no problem that the liquid receives resistance in the first sub-liquid chamber and the anti-vibration characteristics are not sufficiently exhibited. Further, since the volume of the first sub-liquid chamber is large, the area of the first diaphragm can be increased, and even if a large amount of liquid enters and leaves the first sub-liquid chamber during large-amplitude vibration, The deformation of the diaphragm is small. Therefore, the first diaphragm does not exert a large tension and has good durability.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a vibration isolation device 10 according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, the anti-vibration device 10 is provided with a mounting frame 12 for mounting on a vehicle body (not shown), and an outer cylinder 16 is provided in an annular portion 14 of the mounting frame 12. Press-fitted and fixed. The outer cylinder 16 may be fixed by caulking both ends of the annular portion 14. A large rectangular hole 18 is formed on the lower side of the outer cylinder 16. A thin rubber layer 20 is vulcanized and adhered to the inner peripheral surface of the outer cylinder 16, and as shown in FIG.
A part of the thin rubber layer 20 is closed by a diaphragm 22 formed so as to project inward of the outer cylinder 16. An air chamber 24 is provided between the diaphragm 22 and the annular portion 14.
And is communicated with the outside as needed.

As shown in FIG. 3, the inner cylinder 2 is placed inside the outer cylinder 16.
6 are arranged in the same direction. As shown in FIG. 2, an intermediate cylinder 28 is arranged between the inner cylinder 26 and the outer cylinder 16 coaxially with the outer cylinder 16. As shown in FIG. 1, circular flanges 30 viewed from the axial direction are provided at both ends of the intermediate cylinder 28 in the axial direction, and as shown in FIG. 3, the outer peripheral surface is in close contact with the thin rubber layer 20. is doing. The intermediate cylinder 28
By crimping both ends of the outer cylinder 16
It is fixed in 6.

As shown in FIG. 1, the intermediate portion of the intermediate cylinder 28 in the axial direction is a reduced diameter portion 30B. As shown in FIGS. 2 and 3, an elastic body 32 is disposed between the inner cylinder 26 and the intermediate cylinder 28, and the elastic bodies 32 are the outer peripheral surface of the inner cylinder 26 and the inner peripheral surface of the intermediate cylinder 28, respectively. It is vulcanized and bonded.
Further, the elastic body 32 is formed with a through hole 34 which is axially penetrated above the inner cylinder 26.

The elastic body 32 has a recess 36 cut out toward the inner cylinder 26 toward the large rectangular hole 18 of the outer cylinder 16.
Are formed. The concave portion 36 is surrounded by a partition plate 40 arranged corresponding to the cutout portion 30C formed on the lower side of the small diameter portion 30B of the intermediate cylinder 28 to form a main liquid chamber 42. Further, a first sub liquid chamber 44 is formed between the partition plate 40 and the diaphragm 22. As shown in FIG. 1, the partition plate 40 is formed with a pair of side wall portions 40A facing each other, and a top plate portion 40B continuous with the side wall portion 40A is formed at one end of the side wall portions 40A. The side wall portion 40
A flange portion 40C bent at a right angle on the outer cylinder 16 side of A
Are continuously formed. As a result, the partition plate 40 has a substantially hat-shaped cross section along the axis, as shown in FIG. Further, as shown in FIG. 1, a bent portion 40D is formed at one longitudinal end of the top plate portion 40B. The flange portion 40C of the partition plate 40 is the reduced diameter portion 30 of the intermediate cylinder 28.
It is sandwiched between A and the thin rubber layer 20.

As shown in FIG. 1, the small diameter portion 3 of the intermediate cylinder 28.
A recess 46 is formed on the upper side of 0B.
A rib 48 is provided upright along the circumferential direction at the central portion in the axial direction of 6. As shown in FIGS. 1 and 2, semicircular arc-shaped notches 50 are formed in the vicinity of both longitudinal ends of the rib 48. Further, as shown in FIGS. 1, 2 and 4, in the intermediate cylinder 28, square holes 52 penetrating the intermediate cylinder 28 inward and outward are formed at predetermined intervals at intersections of the recess 46 and the flange portion 30. Four are formed. 2 (A) and FIG.
As shown in (B), these square holes 52 are formed in a recess 46 by a small diaphragm 54 formed of a thick elastic body.
It is blocked from the side.

Each of the small diaphragms 54 has a semicircular cross section perpendicular to the axis, and is convex outward in the radial direction of the intermediate cylinder 28. The edge portions of these small diaphragms 54 are vulcanized and adhered to the periphery of the opening of the square hole 52 of the recess 36. The axial center side of the small diaphragm 54 faces the outside air through the through hole 34.
The small diaphragm 54 is the diaphragm 22.
Rigidity is higher than.

As shown in FIG. 2, the concave portion 36 is closed by a limiting passage forming member 56 to form a second auxiliary liquid chamber 58. The restricted passage forming member 56 has a substantially semicircular arc shape, and the outer peripheral surface thereof is in close contact with the thin rubber layer 20. As shown in FIGS. 1 and 3, thin portions 56A are formed at both axial ends of the restricted passage forming member 56.
A is the reduced diameter portion 3 formed on the flange portion 30 of the intermediate cylinder 28.
It is sandwiched between 0A and the thin rubber layer 20 of the outer cylinder 16. Further, a narrow groove 60 and a wide groove 62 are formed on the outer periphery of the restricted passage forming member 56 along the circumferential direction.

As shown in FIG. 3, the fine groove 60 is arranged on the arrow B direction side in FIG. 3 with the rib 48 as a boundary, and as shown in FIG. It is connected to the chamber 42 and the other end is connected to the first sub liquid chamber 44 via the small diameter portion 30B. The narrow groove 60 is surrounded by the outer cylinder 16 to form a first limiting passage 64.

On the other hand, the wide groove 62, as shown in FIG.
It is disposed on the arrow F direction side in FIG. 3 with the rib 48 as a boundary, and as shown in FIG. 4, one end is connected to the main liquid chamber 42 via the small diameter portion 30B and the other end sandwiches the inner cylinder 26. Through the opening 65 formed on the side opposite to the one end of the second sub liquid chamber 58.
Is connected with. The wide groove 62 is formed by the outer cylinder 16
The second limiting passage 66 is surrounded by.

A stopper metal fitting 68 is fixed to the inner cylinder 26 on the partition plate 40 side. The stopper fitting 68 is covered with the elastic body 32 to form the stopper portion 70, and limits the amount of movement of the inner cylinder 26 toward the partition plate 40.

The main liquid chamber 42, the first sub-liquid chamber 44, the second
Sub liquid chamber 58, first limiting passage 64, and second limiting passage 6
6 is filled with a liquid such as water or oil.

Next, the operation of this embodiment will be described. When the mounting frame 12 is mounted on a vehicle body (not shown) and the inner cylinder 26 is connected to an engine (not shown), vibration of the engine is supported by the vehicle body (not shown) via the inner cylinder 26, the elastic body 32, the outer cylinder 16, and the mounting frame 12. .. At this time, the elastic body 32
Is elastically deformed and the vibration of the engine is absorbed by the damping action based on internal friction.

When the vibration of the engine has a low frequency and a large amplitude (as an example, a shake vibration having a frequency of less than 15 Hz and an amplitude of about ± 1 mm), the liquid in the main liquid chamber 42 passes through the first limiting passage 64 to the first limiting passage 64. It goes back and forth between the sub liquid chamber 44. Here, since the small diaphragm 54 of the second sub liquid chamber 58 is thicker and has higher rigidity than the diaphragm 22 of the first sub liquid chamber 44, it is hardly deformed, and the volume change of the second sub liquid chamber 58 is small and the second sub liquid chamber 58 is small. The liquid does not flow in the restriction passage 66. Therefore, the liquid is the first
The shake resistance is absorbed by the passage resistance or the liquid column resonance in the restriction passage 64.

Since only the main liquid chamber 42 and the first sub-liquid chamber 44 are provided on one side of the inner cylinder 26 in the vibration isolator 10, three liquid chambers are provided on one side of the inner cylinder. The capacity of the first sub-liquid chamber 44 can be made larger than that of the conventional vibration damping device, and accordingly, the area of the diaphragm 22 can be made larger. For this reason, the liquid is not subjected to resistance in the first sub liquid chamber 44, the liquid can effectively move back and forth in the first restriction passage 64, and a large loss coefficient can be obtained. Further, since the shake vibration has a large amplitude, a large amount of liquid enters and leaves the first sub-liquid chamber 44 during the shake vibration, but the diaphragm 22 forming the partition wall of the first sub-liquid chamber 44 has a large area and therefore the deformation amount is small. Large tension does not act on the diaphragm 22. Therefore, the diaphragm 22 has good durability.

When the vibration frequency of the engine becomes slightly higher (20-40 Hz idle vibration as an example), the first limiting passage 64 becomes clogged. Therefore, the liquid in the main liquid chamber 42 passes through the second limiting passage 66 and deforms the small diaphragm 54 to move back and forth between the main liquid chamber 42 and the second sub-liquid chamber 58, and the liquid in the second limiting passage 66. The liquid column resonates to reduce the dynamic spring constant and absorb the idle vibration. Also,
The second auxiliary liquid chamber 58 of the vibration isolator 10 is isolated from the main liquid chamber 42 and the first auxiliary liquid chamber 44 with the inner cylinder 26 interposed therebetween, and thus has a high degree of freedom in design, and the capacity and the small diaphragm 54.
Can be set to an optimum size, and the idle vibration absorption effect is also improved.

(Experimental Example) In Table 1 below, the results of the vibration damping characteristic test of the vibration damping device 10 of this embodiment are shown in a graph.

[0031]

[Table 1] From the test shown in Table 1 above, it is clear that the vibration damping device 10 of the present embodiment has a larger loss coefficient during shake vibration than the vibration damping device of the conventional example.

[Second Embodiment] Anti-vibration device 10 according to the present invention
A second embodiment will be described with reference to FIGS. The same components as those in the first embodiment are designated by the same reference numerals,
The description is omitted.

As shown in FIGS. 5 and 6, in the vibration isolator 10 of this embodiment, the concave portion 46 of the intermediate cylinder 28 has the flange 3 formed therein.
A partition 72 connecting 0s is divided into two in the directions of arrows L and R. The side of the partition 72 in the direction of the arrow L in FIG. 6 is the second auxiliary liquid chamber 58, and the side of the partition 72 in the direction of the arrow R in the FIG. 6 is the third. It is a sub liquid chamber 74. Further, the square hole 52 corresponding to the third auxiliary liquid chamber 74 is made smaller than the square hole 52 corresponding to the second auxiliary liquid chamber 58, and the small diaphragm 54 corresponding to the third auxiliary liquid chamber 78 is the first. It is made thicker and has higher rigidity than the small diaphragm 54 corresponding to the second sub-liquid chamber 58.

Further, the narrow passage 6 is formed in the restricted passage forming member 56.
5, a groove 76 having a width wider than that of the wide groove 62 is formed on the arrow B direction side in FIG. As shown in FIG. 7, one end of this groove 76 is connected to the main liquid chamber 4 via the small diameter portion 30B.
2 and the other end is connected to the third auxiliary liquid chamber 7 through the opening 78.
It is connected with 4. The groove 78 is surrounded by the outer cylinder 16 to form a third restriction passage 80.

Therefore, a vibration having a frequency higher than that of the idle vibration (for example, a small amplitude vibration in the vicinity of a frequency of 100 to 300 Hz which causes a high-frequency muffled sound) is input to the vibration isolator 10 and the second limiting passage 66 is formed. Even in the clogging state, the liquid in the main liquid chamber 42 passes through the third restriction passage 80 to deform the small diaphragm 54 of the third auxiliary liquid chamber 74 and move back and forth between the liquid and the third auxiliary liquid chamber 74. You can As a result, the liquid resonates in the liquid in the third restriction passage 80 to reduce the dynamic spring constant of the vibration isolator 10, and it is possible to absorb the high frequency vibration that causes the high frequency muffled noise.

(Experimental Example) In Table 2 below, the results of the vibration damping characteristic test of the vibration damping device 10 of this embodiment are shown in a graph.

[0037]

[Table 2] As shown in Table 2 above, in the vibration damping device 10 of the present embodiment,
The dynamic spring constant is reduced in the high-frequency vibration range (around 100 to 300 Hz) due to the liquid column resonance effect in the third restriction passage 80. In the first embodiment, the first sub-liquid chamber 44 and the second sub-liquid are used. The chamber 58 is connected in parallel to the main liquid chamber 42, but the present invention is not limited to this, and the main liquid chamber 42, the first sub liquid chamber 44, and the second sub liquid chamber 58 may be connected in series. Good.

In the second embodiment, the first sub-liquid chamber 44,
The second sub liquid chamber 58 and the third sub liquid chamber 74 are connected in parallel to the main liquid chamber 42, but the present invention is not limited to this, and the main liquid chamber 4 is not limited to this.
2, first sub-liquid chamber 44, second sub-liquid chamber 58 and third sub-liquid chamber 7
4 may be connected in series.

[0039]

As described above, since the vibration isolator of the present invention has the above-mentioned constitution, it is possible to improve the durability of the diaphragm and prevent the diaphragm from having excessive loss by preventing excessive tension from being generated at the time of large-amplitude vibration. It has an excellent effect that can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a vibration isolation device according to a first embodiment of the present invention.

FIG. 2 shows a vibration damping device according to a first embodiment of the present invention,
(A) is a sectional view taken along the line II-II in FIG. 3, and (B) is a line II in FIG. 2 (A).
It is a B-IIB sectional view.

FIG. 3 is a sectional view taken along the axis of the vibration damping device according to the first embodiment of the present invention.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3, showing the vibration damping device according to the first embodiment of the present invention.

FIG. 5 is a perspective view showing a vibration damping device according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a vibration isolator according to a second embodiment of the present invention, taken along a second restriction passage.

FIG. 7 is a cross-sectional view showing a vibration isolator according to a second exemplary embodiment of the present invention, taken along a third restricted passage.

[Explanation of symbols]

 10 Vibration Isolator 16 Outer Cylinder 22 Diaphragm 26 Inner Cylinder 28 Intermediate Cylinder 32 Elastic Body 36 Recess (First Recess) 40 Partition Plate (Partition Member) 42 Main Liquid Chamber 44 First Sub Liquid Chamber 56 Restricted Passage Constituent Member 58 Number 2 Sub-liquid chamber 64 First limiting passage 66 Second limiting passage 80 Third limiting passage

Claims (1)

[Claims] 1. An outer cylinder connected to one of the vibration generator and the vibration receiver, an inner cylinder connected to the other of the vibration generator and the vibration receiver, and between the outer cylinder and the inner cylinder. An elastic body provided, an intermediate cylinder provided between the outer cylinder and the inner cylinder via the elastic body, and a first wall provided on the elastic body and having a wall surface deformed when vibration occurs. A recess and the first
Partition member for closing the concave portion, a main liquid chamber constituted by the first concave portion and the partition member, and the partition member provided on the opposite side of the partition member from the first concave portion side and covering the partition member. A diaphragm, a first sub-liquid chamber constituted by the diaphragm and the partition member, a restricting passage forming member provided on the opposite side of the inner cylinder from the first sub-liquid chamber, and the inner cylinder. A second auxiliary liquid chamber provided between the restriction passage constituent member and a restriction passage provided in the restriction passage constituent member and connecting the main liquid chamber, the first auxiliary liquid chamber, and the second auxiliary liquid chamber to each other. An anti-vibration device comprising: