JPH10159889A - Fluid mount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid mount with damping effect in low frequency vibration and damping effect in high frequency vibration combined by using less structural elements. SOLUTION: A fluid mount has an outside cylindrical member 1 and an inside cylindrical member 2, an elastic body 3 mounted between the outside cylindrical member 1 and the inside cylindrical member 2, plural liquid chambers 4 formed by the outside cylindrical member 1, the inside cylindrical member 2 and the elastic body 3 to fill fluid therein and an orifice 5 communicated with the liquid chambers 4 via a communication hole 6. The orifice 5 is formed of elastic material and the fluid mount is formed in approximately cylindrical shape so that the orifice 5 can be formed in approximately annular shape along the outside cylindrical member 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid mount that is disposed between a suspension member and a vehicle body or a power plant and a vehicle body and that reduces vehicle interior noise caused by input from a power train system.

[0002]

2. Description of the Related Art As a conventional fluid mount, for example, there is a fluid mount as shown in FIGS. 7 and 8 (first conventional example). Here, FIG. 7 is a cross-sectional view showing a conventional fluid mount, and FIG. 8 is a CC cross-sectional view in FIG. In this conventional example, a pair of liquid chambers 14, 1 is provided between an outer tubular member 11 and an inner tubular member 12 by an elastic body 13 elastically connecting the outer tubular member 11 and the inner tubular member 12.
4 are formed, and the two liquid chambers 14, 14 communicate with an orifice 15 disposed along the outer tubular member 11 through a communication hole 16. Either the outer cylinder member 11 or the inner cylinder member 12 is on the vibration transmission side, and the other is on the transmission side, and the liquid in the two liquid chambers 14 and 14 is subjected to the vibration input by the outer cylinder member 11 and the inner cylinder member. 12 through the orifice 15 due to the relative displacement with respect to the liquid chamber 12 from the other liquid chamber 1
By flowing to 4, a damping effect is exhibited in a wide frequency range from a low frequency to a high frequency.

As a conventional fluid mount, for example, there is a fluid mount (second conventional example) described in Japanese Patent Application Laid-Open No. 7-127684. This conventional example,
It has a pair of liquid chambers between the inner and outer cylinders, and a thin film part is provided on a partition part separating the two liquid chambers, and both liquid chambers are communicated by an orifice passage, so that a wide frequency range from low frequency to high frequency is provided. Can exhibit a damping effect.

[0004]

However, in the first conventional example, when the outer cylindrical member 11 is set as the vibration transmission side and the inner cylindrical member 12 is displaced (for example, ΔX1), When the cylindrical member 12 is displaced at a very high speed (high-frequency vibration), the displacement of the inner cylindrical member 12 (ΔX1)
Causes the outer cylindrical member 11 to be displaced, but the orifice 15
The liquid inside has a large inertial force, and its displacement (for example, ΔX
2) is smaller and the flow of the liquid to the other liquid chamber is smaller. When the inner cylindrical member 12 is displaced at a very low speed (low-frequency vibration), the inertial force and passage resistance of the liquid in the orifice 15 are small, and the displacement of the inner cylindrical member 12 (ΔX
Since the liquid in the orifice 15 is displaced (△ X2) by 1), the liquid passes through the orifice 15 and flows from one liquid chamber to the other liquid chamber, and the displacement of the outer cylindrical member 11 does not occur. As described above, in a high frequency region higher than the frequency at which the attenuation becomes maximum, the liquid sticks in the orifice 15 so that the liquid does not flow, so that the dynamic spring constant increases and the vibration is easily transmitted to the vehicle body side. The room sound pressure level could be worse. In the second conventional example,
Since it is necessary to separately provide the thin film portion of the partition portion separating the two liquid chambers and the orifice, there has been a problem that the number of parts increases. In view of the above, the present invention has been made by focusing on the unsolved problems of the above conventional example, and aims at achieving both the damping effect at low frequency vibration and the damping effect at high frequency vibration with a small number of components in a fluid mount. The purpose is to:

[0005]

According to another aspect of the present invention, there is provided a fluid mount which is mounted between an outer tubular member and an inner tubular member, and between the outer tubular member and the inner tubular member. An elastic body, a plurality of liquid chambers formed by the outer cylindrical member and the inner cylindrical member, and the elastic body; a fluid is sealed in the plurality of liquid chambers; and a communication hole is provided between the plurality of liquid chambers. A fluid mount comprising an orifice communicating through
The orifice is formed of an elastic material. A fluid mount according to a second aspect is characterized in that, in the first aspect, the orifice is formed integrally with the elastic body. Furthermore, the fluid mount according to claim 3 is the fluid mount according to claim 1 or 2, wherein the fluid mount is substantially cylindrical, and the orifice is formed in a substantially annular shape along the outer cylindrical member. It is characterized by.

[0006]

Hereinafter, a first embodiment of the present invention will be described.
Will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a fluid mount according to Embodiment 1 of the present invention.
FIG. 2 is a sectional view taken along the line A-A in FIG. 1. A pair of liquid chambers 4 and 4 are formed by an elastic body 3 interposed between the outer cylindrical member 1 and the inner cylindrical member 2 and elastically connecting the outer cylindrical member 1 and the inner cylindrical member 2. The chambers 4 and 4 are communicated with an orifice 5 arranged along the outer tubular member 1 through a communication hole 6. Further, the orifice 5 is formed in a tubular shape by an elastic material that can expand and contract in the radial direction of the orifice, and is fixed to the outer tubular member 1 in an annular shape.

In the first embodiment, since the member forming the orifice 5 is made of an elastic material and is made of an elastic tube which expands and contracts in the radial direction of the orifice, the inner cylindrical member 2 is, for example, extremely upward in the drawing shown in FIG. 3 and 4 will be described with reference to FIGS. Here, FIG.
FIG. 4 is an explanatory view showing deformation of the orifice 5 due to relative displacement between the inner tubular member 2 and the outer tubular member 1 of the fluid mount of the first embodiment. FIG. 4 is an explanatory view showing characteristics of the fluid mount of the present invention. It is. When the inner cylinder member 2 is displaced upward at a very high speed on the drawing shown in FIG. 3, as shown in FIG. 4, the displacement of the inner cylinder member 2 causes the upper liquid chamber pressure to become P1 and the lower liquid chamber pressure to become P1. It becomes P2 (however, P2 <P1), and the pressure in the orifice 5 takes a pressure gradient from P1 to P2. At this time, the shape of the orifice 5 is deformed to reduce the change in the liquid pressure in the upper liquid chamber 4 due to the relationship between the pressure in the liquid chamber 4 and the pressure gradient in the orifice 5. In other words, this is equivalent to the liquid in the orifice 5 being displaced in a direction to reduce the pressure change, and the liquid pressure change due to the displacement (vibration) of the inner cylindrical member 2 is absorbed by the shape deformation of the orifice 5 as shown in FIG. I do.

As the rigidity of the elastic tube forming the orifice 5 is lower, the change in the hydraulic pressure of the high-frequency component is more easily absorbed by the deformation of the elastic tube. Vibration transmitting force is reduced. Even if the rigidity of the elastic tube is set to be relatively low, the low-frequency component is balanced to some extent in the liquid chamber 4 and the orifice 5, so that the orifice 5 is not crushed by the liquid pressure. As described above, in the first embodiment, since the pressure fluctuation of the high frequency component in the liquid chamber 4 is absorbed by the orifice 5 formed of the elastic material, the number of components is small.
It is possible to achieve both a damping effect in low frequency vibration and a damping effect in high frequency vibration.

Next, a second embodiment of the present invention will be described with reference to the drawings showing a fluid mount according to the second embodiment shown in FIGS. Here, FIG. 5 is a cross-sectional view showing a fluid mount according to Embodiment 2 of the present invention,
FIG. 6 is a sectional view taken along line BB in FIG. The basic concept is the same as in the first embodiment, except that the orifice 5
Are integrally molded as a part of the elastic body 3. Note that the other configuration and operation and effect are the same as those of the first embodiment, and the corresponding components are denoted by the same reference numerals and description thereof will be omitted. Thus, in the second embodiment,
In addition to the effects of the first embodiment, since the orifice 5 is integrally formed with the elastic body 3, the structure is simplified, and the cost can be further reduced.

Although the embodiments of the present invention have been described in detail above, the specific configuration is not limited to the above-described embodiments, and even if there is a design change or the like within a range not departing from the gist of the present invention. Included in the invention. For example, in the above-described embodiment, the case where the number of liquid chambers is two (a pair of liquid chambers) is described. However, the number of liquid chambers is not limited to two, and the present invention is applied to two or more liquid chambers. It is possible to The application of the fluid mount of the present invention to a vehicle can be applied to a rear differential mount of a differential gear, a power plant, a member supporting a power plant, and the like.

[0011]

According to the first aspect of the present invention, since the pressure fluctuation of the high-frequency component in the liquid chamber of the fluid mount is absorbed by the orifice formed of the elastic material, the number of components and the low-frequency vibration can be reduced. The effect that both the damping effect and the damping effect by high-frequency vibration can be achieved is obtained. According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, since the orifice is integrally formed with the elastic body, the structure can be simplified and the cost can be further reduced. can get. Further, according to the third aspect of the present invention, since the orifice is formed of a single elastic material or is integrally molded with the elastic body, the orifice is formed along the outer cylinder so as to have an orifice shape (a substantially annular shape). ) Can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a fluid mount according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is an explanatory diagram showing deformation of an orifice accompanying relative displacement between an inner cylindrical member and an outer cylindrical member of the fluid mount according to the first embodiment.

FIG. 4 is an explanatory diagram showing characteristics of the fluid mount of the present invention.

FIG. 5 is a cross-sectional view showing a fluid mount according to a second embodiment of the present invention.

6 is a sectional view taken along line BB in FIG.

FIG. 7 is a cross-sectional view showing a conventional fluid mount.

8 is a sectional view taken along the line CC in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer cylinder member 2 Inner cylinder member 3 Elastic body 4 Liquid chamber 5 Orifice 6 Communication hole

Claims (3)

[Claims] 1. An outer tubular member and an inner tubular member, an elastic body loaded between the outer tubular member and the inner tubular member, and the outer tubular member, the inner tubular member, and the elastic body. In a fluid mount including a plurality of liquid chambers and an orifice in which fluid is sealed inside the plurality of liquid chambers and communicating between the plurality of liquid chambers through communication holes, the orifice is formed of an elastic material. A fluid mount characterized in that: 2. The fluid mount according to claim 1, wherein the orifice is formed integrally with the elastic body. 3. The fluid mount according to claim 1, wherein the fluid mount has a substantially cylindrical shape, and the orifice is disposed in a substantially annular shape along the outer tubular member.