JPH0716129Y2 - Liquid-filled mount - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a liquid-filled mount for use in automobiles, and in particular, a low spring constant is obtained in a high frequency range and a high damping characteristic is obtained in a low frequency range. And a liquid-filled mount.

[Conventional technology]

As prior arts related to the present invention, there are known JP-A-60-139940, JP-A-60-71749, JP-A-60-143947, and JP-A-62-25348.

The anti-vibration device disclosed in Japanese Unexamined Patent Publication No. 60-139940 is provided with a plurality of circumferentially spaced liquid chambers in an elastic body that connects the inner cylinder and the outer cylinder, and each of the liquid chambers is surrounded. By communicating with each of the directional and axial throttle passages, vibrations in all directions can be damped. Other Japanese Utility Model Laid-Open Nos. 60-71749, 60-143947, and 62-25348 also disclose a vibration-proof structure in which a liquid is enclosed.

A conventional liquid-filled mount is, for example, the actual open sho 62-2534.
As disclosed in Japanese Patent No. 8, it has a tubular orifice, and in the vibration of a low frequency range of 10 to 20 Hz,
High damping characteristics can be obtained.

However, depending on the structure of the tubular orifice that increases the damping coefficient in the low frequency range, the spring constant becomes large in the high frequency range of 100 to 500 Hz. When the spring constant increases, the vibration transmission increases, which causes a problem that the riding comfort of the vehicle and the bass sound of the vehicle deteriorate.

Therefore, a low dynamic spring constant can be obtained by vibration at high frequencies,
In addition, a liquid-filled mount that can obtain high damping characteristics in vibrations in a low frequency range has been previously proposed by the present applicant (Japanese Patent Application No. 62-184388).

In this liquid-filled mount, as shown in FIG. 3, the inner cylinder 1 and the outer cylinder 2 are connected by elastic bodies 3 and 4, and the liquid is sealed between the inner and outer cylinders by the elastic bodies 3 and 4. Liquid chamber 5
Are formed. The liquid chamber 5 is fixed to either one of the inner cylinder 1 and the outer cylinder 2 (fixed to the inner cylinder 2 in the figure) and is elastically deformable by high frequency vibration in the axial direction. 6 and the second liquid chamber 7. Then, the first liquid chamber 6 and the second liquid chamber 7 are communicated with each other by a circumferentially extending flow passage 9 formed between the elastic partition 8 and the inner and outer cylinders.

In such a liquid-filled mount, a damping force is obtained due to the flow resistance when the liquid passes through the flow path when vibrating in a low frequency range. Further, when vibrating in a high frequency range, a phase difference of forces occurs due to a resonance phenomenon, so that the spring constant can be reduced.

[Problems to be solved by the device]

However, in the above liquid-filled mount,
When a lateral force (a direction perpendicular to the axial direction) acts, the circumferential distance (gap) between the elastic partition wall and the inner and outer cylinders changes significantly, and the axial damping coefficient is maintained at a substantially constant value. However, there is a problem in that stable attenuation characteristics cannot be obtained.

It is an object of the present invention to provide a liquid-filled mount capable of maintaining a constant damping coefficient in the axial direction and obtaining stable damping characteristics.

[Means for Solving the Problems]

A liquid-filled mount according to the present invention which meets this object connects an inner cylinder and an outer cylinder via an elastic body arranged at a distance in the axial direction, and the elastic body seals liquid between the inner and outer cylinders. And an elastic partition wall that is elastically deformable at the time of high frequency vibration in the axial direction is fixed to the outer cylinder with a slight gap from the inner cylinder, and the elastic partition separates the liquid chamber from the first chamber. It is divided into a liquid chamber and a second liquid chamber, and on the elastic partition,
An orifice that connects the first liquid chamber and the second liquid chamber is provided, and the elastic partition wall has a V-shaped cross-section in the radial direction.

[Action]

In the liquid-filled engine mount configured as described above, when axial displacement acts on the inner cylinder during vibration in the low frequency range, the volume of one liquid chamber decreases depending on the vibration direction, and The volume of the other liquid chamber is expanded. Thereby, for example, the liquid in the first liquid chamber flows into the second liquid chamber through the gap between the elastic partition wall and the inner cylinder and the orifice, and the flow resistance when the liquid passes through each flow path. Causes a damping force.

The elastic partition wall is fixed to the outer cylinder with a slight gap from the inner cylinder, and the radial partition section of the elastic partition wall is V-shaped, so that the elastic partition wall is easily stretched and deformed in the radial direction. Therefore, the followability in the direction perpendicular to the axial direction due to the contact of the elastic partition wall with the inner cylinder can be improved. Therefore,
Even if the inner cylinder comes into contact with the elastic partition wall and is pressed by the force in the direction perpendicular to the axial direction, the part opposite to the contact part is easily pulled to the contact part side, and the part opposite to the contact part The gap between the parts does not become extremely large. That is, there is no great difference between the circumferential gap in this case and the gap when this load is not applied. Therefore, the damping coefficient in the axial direction can be maintained at a substantially constant value, and stable damping characteristics can be obtained.

At the time of vibration in a high frequency range, when an axial force similarly acts on the inner cylinder, the volumes of the first liquid chamber and the second liquid chamber change, but since the frequency is high, the liquid is The resistance when passing through the gap and the orifice becomes large. That is, the situation is the same as when the gap and the orifice are clogged. Therefore, the liquid in the first liquid chamber cannot pass through the gap and the orifice, and the elastic partition wall is elastically deformed. When the elastic partition is elastically deformed, the liquid in that portion flows in the axial direction according to the elastic deformation of the elastic partition, and a resonance phenomenon occurs due to the mass of the liquid and the volume elasticity of the first liquid chamber and the second liquid chamber. . Under such a resonance phenomenon, a phase difference of forces occurs, so that the spring constant can be kept at a low value up to the resonance frequency, and the spring constant can be reduced in the high frequency range.

〔Example〕

Hereinafter, a preferred embodiment of a liquid-filled mount according to the present invention will be described with reference to the drawings.

FIG. 1 and FIG. 2 show an embodiment of the present invention, particularly an example applied to a mount used for a suspension of an automobile. In the figure, 11 indicates an inner cylinder, and an outer cylinder 12 is arranged on the outer periphery of the inner cylinder 11. Outer cylinder
The upper end of 12 projects more than the upper end of the inner cylinder 11, while the lower end of the inner cylinder 11 projects more than the lower end of the outer cylinder 12. The upper end of the outer cylinder 12 is formed with a flange portion 13 that bulges outward in the radial direction. A reinforcing member 14 extending in the circumferential direction and having a substantially L-shaped cross section is located inside the upper end of the outer cylinder 12. The lower end of the reinforcing member 14 slightly projects inward in the radial direction.
The outer peripheral portion of the flange portion 13 is bent inward in the radial direction, and the outer peripheral end of the reinforcing member 14 is wrapped and held by the bent portion 15.

The inner cylinder 11 and the outer cylinder 12 are supporting rubbers as elastic bodies which are located between the inner and outer cylinders and are arranged at intervals in the axial direction (axis A direction).
16 and a rubber diaphragm 17 as an elastic body. The inside of the support rubber 16 is joined to the outer peripheral surface of the inner cylinder 11, and the outside of the support rubber 16 is joined to the inner peripheral surface of the reinforcing member 14 and the inner peripheral surface of the outer cylinder 12. The portion of the support rubber 16 joined to the inner peripheral surface of the outer cylinder 12 serves as a seal member. The inner side of the diaphragm 17 is joined to the outer peripheral surface of the seal ring 18 press-fitted into the inner cylinder 11, and the outer side of the diaphragm 17 is joined to the inner peripheral surface of the lower end portion of the outer cylinder 12. An auxiliary member extending in the axial direction is provided near the center of the support rubber 16.
31 is installed. Further, the support rubber 16 is provided with a cavity portion 19 that reduces the rigidity in the radial direction.

A liquid chamber 20 is formed between the inner cylinder 11 and the outer cylinder 12 by surrounding the support rubber 16 and the diaphragm 17. Liquid chamber 20
Silicon oil, ethylene glycol, or the like, for example, is sealed inside. The liquid chamber 20 is provided with an elastic partition wall 41 made of an elastic body that divides the liquid chamber 20 into a first liquid chamber 21 and a second liquid chamber 22. The elastic partition wall 41 has a V-shaped cross section in the radial direction, which is bent in the axial direction.
Is fixed to the outer cylinder 12 with a slight gap 24. That is, a gap 24 extending in the circumferential direction is formed between the inner peripheral surface of the elastic partition wall 41 and the outer peripheral surface of the inner cylinder 22. In the present embodiment, the outer peripheral surface of the elastic partition wall 41 is joined to the ring member 25 for the convenience of production, and the ring member 25 is press-fitted into the outer cylinder 12. Thereby, the elastic partition wall 41 is fixed to the outer cylinder side.

The reason why the elastic partition wall 23 has a V-shaped cross-section in the radial direction is to facilitate the elastic deformation and extension of the elastic partition wall 23 in the radial direction. It can easily follow the displacement in the right angle direction.

The elastic partition wall 41 is made of natural rubber or a material obtained by mixing a small amount of styrene-butadiene rubber with natural rubber. The thickness of the elastic partition wall 41 is 4 to 6 m in this embodiment.
The clearance between the elastic partition wall 41 and the inner cylinder 11 is set to about 0.5 mm.

A circular rigid plate 26 is arranged in the first liquid chamber 21, and the rigid plate 26 is fixed to the inner cylinder 11. A gap 27 is formed between the outer peripheral surface of the rigid plate 26 and the inner peripheral surface of the outer cylinder 12, and when the inner cylinder 11 is largely displaced in the direction perpendicular to the axial direction, the rigid plate 26 causes the outer cylinder 12 to move. It comes into contact with.

The elastic partition wall 41 is provided with a tubular orifice 30 that connects the first liquid chamber 21 and the second liquid chamber 22. Orifice
Reference numeral 30 is for flowing a fluid from one liquid chamber to the other liquid chamber when the inner cylinder 11 moves in the axial direction, and a damping force is generated by the flow resistance at this time. The orifice
The members constituting 30 are made of resin such as plastic material.

The outer cylinder 12 is fitted and held in a hole 34 formed in the body of the automobile. A flange member 36 is provided on the upper end surface of the inner cylinder 11, and a bolt 37 is inserted into the flange member 36 and the inner cylinder 11. The flange member 36 bulges outward in the radial direction, and its diameter is substantially the same as the diameter of the flange member 13 of the outer cylinder 12. A stopper made of an elastic body having a triangular cross section is provided on the top surface of the reinforcing member 14 located immediately above the flange member 13.
38 are joined. The stopper 38 is integrally formed with the above-mentioned support rubber 16 in manufacturing. The flange member 36 is capable of contacting the stopper 38, and a gap is formed between the flange member 36 and the stopper 38 when the vehicle is stopped. A suspension differential device 39 is connected to the lower end of the bolt 37.

Next, the operation of the liquid-filled mount will be described.

Inner cylinder connected to the suspension via bolts 37
11, when the load is applied from the top of the figure, the first liquid chamber
The volume of 21 is reduced and the volume of the second liquid chamber 22 is increased. In other words, since the supporting rubber 16 is hard to be deformed at the outer peripheral portion by the reinforcing member 14, the supporting rubber 16 and the elastic partition wall are
The first liquid chamber 21 located between the first liquid chamber 21 and 41 is reduced by the movement of the elastic partition wall 41 accompanying the movement of the inner cylinder 11. This allows
The liquid in the liquid chamber 20 flows from the first liquid chamber 21 into the second liquid chamber 22. In this case, the liquid flows into the second liquid chamber 22 through the gap 24 and the orifice 30, and the flow resistance when passing through the gap 24 and the orifice 30 provides high damping characteristics.

In this case, since the gap 24 between the elastic partition wall 41 and the inner cylinder 11 is significantly smaller than that of the conventional structure, the inner cylinder 11 abuts on the elastic partition wall 41 by the force in the direction perpendicular to the axial direction, and Partition wall 41
Even if is pressed, the portion on the opposite side of the contact portion with the elastic partition wall 41 is also pulled by the contact portion, so that the gap 24 on the opposite side of the contact portion does not become significantly large. In particular, since the radial partition shape of the elastic partition wall 41 is V-shaped so as to project in the axial direction, the elastic partition wall 41 can easily follow the displacement in the direction perpendicular to the axial direction due to the contact with the inner cylinder 11. As a result, the gap 24 in the circumferential direction between the elastic partition wall 41 and the inner cylinder 11 has almost no difference compared to the case where no load acts in the direction perpendicular to the axial direction. Therefore, the damping coefficient in the axial direction can be maintained at a substantially constant value, and stable damping characteristics can be obtained.

In addition, the elastic partition wall 41 has a V-shaped cross section, and
Since the elastic deformation of the elastic partition wall is facilitated, the stress generated in the elastic partition wall 41 can be reduced, and the durability of the elastic partition wall 41 can be enhanced.

When the vibration in the high frequency range is transmitted to the inner cylinder 11, the high vibration causes a large resistance when the liquid passes through the gap 24 and the orifice 30. The elastic partition 41 is elastically deformed by the pressure. Therefore, the liquid near the elastic partition 41 is
The elastic deformation of 41 causes the liquid to flow in the vertical direction, and the resonance phenomenon occurs due to the mass of this liquid and the volume elasticity of the first liquid chamber 21 and the second liquid chamber 22. That is, under such a phenomenon, a force phase difference occurs, so that the mount spring constant maintains a low value up to the resonance frequency. Therefore, the spring constant can be reduced in the high frequency range, and the vibration insulation can be improved.

In this way, high damping characteristics are obtained for vibrations in the low frequency range,
Since a low spring constant can be obtained by vibration in a high frequency range, the riding comfort of the vehicle is improved and the sound inside the vehicle is also reduced.

Further, in this embodiment, since the rigid plate 26 that moves integrally with the inner cylinder 11 is provided between the support rubber 16 and the elastic partition wall 41, the resonance of the resonance system that can be obtained by the mass of the liquid and the volume elastic coefficient of the liquid chamber. The frequency can be 500 Hz or higher. And
Since the spring constant up to the resonance frequency can be lowered,
Vibration transmission can be reduced up to about 500Hz.
Further, when a large load is applied to the inner cylinder 11 in the direction perpendicular to the axial direction, the rigid plate 26 contacts the outer cylinder 12 and serves as a stopper, so that the support rubber 16 and the elastic partition wall 41 are not excessively deformed. Prevented and both protected from destruction.

[Effect of device]

According to the liquid-filled mount according to the present invention, the inner cylinder and the outer cylinder are connected to each other via the elastic body that is arranged at a distance in the axial direction, and the inner cylinder and the outer cylinder are connected by this elastic body. A liquid chamber in which liquid is enclosed is formed, and an elastic partition that is elastically deformable during high-frequency vibration in the axial direction is fixed to the outer cylinder with a slight gap from the inner cylinder. Is divided into a first liquid chamber and a second liquid chamber, an elastic partition is provided with an orifice for communicating the first liquid chamber and the second liquid chamber, and the elastic partition has a radial cross-sectional shape as an axis. Since it has a V-shape that bends in the direction, the volume of each liquid chamber changes with the vibration in the axial direction when vibrating in the low frequency range with large amplitude.
High damping characteristics can be obtained by the flow resistance of the liquid flowing through the gap between the elastic partition wall and the inner cylinder and the orifice.

Further, by making the cross-sectional shape of the elastic partition in the radial direction a V-shape that bends in the axial direction, it is possible to improve the followability in the direction perpendicular to the axial direction due to the contact of the elastic partition with the inner cylinder. Even when the inner cylinder presses the elastic partition wall by the force in the direction perpendicular to the direction, it is possible to suppress the gap caused by this pressing to a small value. Therefore, the damping coefficient in the axial direction can be maintained at a substantially constant value, and stable damping characteristics can be obtained.

Moreover, by making the cross-sectional shape of the elastic partition into a V shape,
The elastic partition wall can be easily expanded and deformed in the radial direction, and the stress generated in the elastic partition wall can be reduced. Therefore, the durability of the elastic partition can be enhanced.

Furthermore, when vibrating in a high frequency range with a small amplitude, the gap between the elastic partition and the inner cylinder and the orifice are closed due to high-speed vibration, and the elastic deformation of the elastic partition and the action of the liquid mass cause resonance. The system can be configured. Therefore, under the resonance phenomenon, a force phase is generated, and the spring constant can be reduced. Therefore, the vibration insulation in the high frequency range is improved, and the riding comfort of the vehicle can be improved and the sound inside the vehicle can be reduced.

[Brief description of drawings]

1 is a sectional view of a liquid-filled mount according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is described in Japanese Utility Model Application No. 62-184388. FIG. 4 is a cross-sectional view of the liquid-filled mount that is used. 11 …… Inner cylinder 12 …… Outer cylinder 16,17 …… Elastic body 20 …… Liquid chamber 21 …… First liquid chamber 22 …… Second liquid chamber 41 …… Elastic partition 24 …… Elastic partition and inner Gap between cylinder 26 …… Rigid plate 30 …… Orifice

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. An inner cylinder and an outer cylinder are connected via an elastic body arranged at a distance in the axial direction, and the elastic body forms a liquid chamber in which liquid is sealed between the inner and outer cylinders. An elastic partition wall that is elastically deformable during high-frequency vibration in the direction is fixed to the outer cylinder with a slight gap from the inner cylinder, and the elastic partition divides the liquid chamber into a first liquid chamber and a second liquid chamber. The elastic partition wall is provided with an orifice that connects the first liquid chamber and the second liquid chamber, and the elastic partition wall has a V-shaped cross-section in the radial direction. Liquid-filled mount featuring.