JP2001221275A - Liquid-filled type vibration-proofing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid-filled type vibration-proofing device constituted of a small number of part items reducing a vibration at a plurality of frequency areas. SOLUTION: This liquid-filled type vibration-proofing device 2 has a rubber elastic body 8 for connecting mounting members 4, 6 each other; a first diaphragm 12 forming a liquid chambers 14 between the rubber elastic body 8 and it, a first partition member 16 for partitioning the liquid chamber 14 to a main liquid camber 18 and a first sub-liquid chamber 20, a second partition member 32 having a projection 50 projected to the main liquid chamber 18 and press-fitted into the first partition member 16, a second diaphragm 42 clamped and fixed by the first partition member 16 and the second partition member 32, a second sub-liquid chamber 44 positioned in the first partition member 6; a first orifice passage 26 for communicating the main liquid chamber 2/18 with the first sub-liquid chamber 20, and a second orifice passage 48 for connecting the main liquid camber 18 with the second sub-liquid chamber 44. A tip end of the projection 50 is opposed to the robber elastic body 8 at a predetermined interval.

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 having a plurality of vibration damping regions.

[0002]

2. Description of the Related Art Since a power unit including an engine of an automobile vibrates in a wide frequency range, a liquid-filled type vibration damping device capable of reducing the vibration generated in a plurality of frequency ranges has been developed.

As a technique of this type of liquid-filled type vibration damping device, for example, there is one disclosed in Japanese Patent Publication No. Hei 6-94888.

Briefly described with reference to FIG. 5, a liquid chamber 56 in which a liquid is sealed is divided into a main liquid chamber 62 and a sub liquid chamber 62 by rubber members 60 vulcanized and bonded to the partition members 58a, 58b, 58c and the partition member 58b. The main liquid chamber 62 is defined between the partition members 58a, 58b, and 58c.
A first orifice passage 66 and a second orifice passage 68 are formed to mutually communicate with the auxiliary liquid chamber 64.

In the main liquid chamber 62, a substantially disc-shaped metal fitting 70 is provided. The metal fitting 70 is attached to a mounting metal 74 fixed to a bracket 72 by a mounting bolt 7.
8 fixed.

[0006] In the liquid filled type vibration damping device 80 thus configured, the liquid filled vibration damping device 8 is actuated by the resonance action of the liquid flowing through the first orifice passage 66.
It is possible to attenuate the shake vibration generated in a frequency region near 10 Hz input to 0.

[0007] Further, the resonance action of the liquid flowing through the second orifice passage 68 can attenuate the idle vibration generated in a frequency range of about 20 to 30 Hz, which is input to the liquid filled type vibration damping device.

[0008] Based on the resonance effect of the flow of the liquid in the main liquid chamber 62 due to the relative displacement of the metal fitting 70 in the main liquid chamber 62 at the time of the vibration input, it is generated in a frequency region of 100 Hz or more. Vibration such as sound can be attenuated.

[0009]

However, in this type of liquid-filled type vibration damping device 80, three partition members 5 have to be formed in order to form two orifice passages 66 and 68.
8a, 58b, and 58c are required.
Need to be fixed with mounting bolts 78, there is a problem that the number of parts as a whole increases and the manufacturing cost increases.

Further, there is a problem that a process of attaching the metal fitting 70 and a process of vulcanizing and bonding the rubber film 60 to the partition member 58b are required, so that the manufacturing cost is increased.

[0011]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a power unit-side mounting member and a vehicle-body-side mounting member which are disposed to face each other, and a rubber for connecting the pair of mounting members to each other. An elastic body, a first diaphragm fixed to one of the pair of mounting members and forming a liquid chamber between the rubber elastic body, and a first diaphragm provided in the liquid chamber and the pair of mounting members. A first partition member fixed to any one of the above, and defining the liquid chamber as a main liquid chamber on the rubber elastic body side and a first sub liquid chamber on the first diaphragm side;
A projection protruding toward the main liquid chamber;
A second partition member press-fitted into the partition member, a second partition member sandwiched and fixed between the first partition member and the second partition member, and sealing between the first partition member and the second partition member.
A second sub-liquid chamber defined by the diaphragm, the second diaphragm, and the second partition member and located inside the first partition member communicates with the main liquid chamber and the first sub-liquid chamber. A first orifice passage to be formed, formed between an inner peripheral surface of the first partition member and an outer peripheral surface of the second partition member,
A second orifice passage for communicating the main liquid chamber with the second sub liquid chamber, wherein a tip of the protrusion faces the rubber elastic body at a predetermined interval. . With this, the resonance effect of the liquid flowing between the protrusion provided on the second partition member and the rubber elastic body causes 100%.
Vibration such as muffled sound generated in a frequency region of not less than Hz is reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
Details will be described with reference to FIG.

The liquid-filled vibration damping device 2 includes a metal mounting member 4 mounted on a power unit side serving as a vibration source.
And a metal attachment member 6 attached to the vehicle body. The attachment members 4 and 6 are connected to each other by a rubber elastic body 8 so as to face each other. The mounting member 6 includes:
A bottom fitting 6a on a bottomed cylinder and a substantially cylindrical upper fitting 6b
By crimping the lower end of the upper fitting 6b, ie, the lower end in FIG. 1, with respect to the upper edge of the bottom fitting 6a, that is, the outer peripheral flange 10 located above in FIG. Are combined. Also,
The inner peripheral surface of the upper fitting 6b is covered with a thin coating 8a extending from the rubber elastic body 8.

A thin, substantially disk-shaped first diaphragm 12 made of a rubber material is mounted inside the mounting member 6.

A liquid chamber 14 in which a liquid is filled is defined between the first diaphragm 12 and the rubber elastic body 8.

The liquid chamber 14 is further defined into a main liquid chamber 18 and a first sub liquid chamber 20 by a first cylindrical metal-made partition member 16 attached to the attachment member 6. ing.

The first partitioning member 16 has a brim-like shape having a larger diameter than the outer diameter of the power unit side end, ie, the upper end in FIG. 1, at the vehicle body end, ie, the lower end in FIG. A flange portion 22 is formed. The outer peripheral edges of the flange portion 22 and the first diaphragm 12 are
Together with the outer peripheral flange 10 of the bottom fitting 6a, it is sandwiched by the lower end of the upper fitting 6b, caulked and fixed. The outer peripheral surface of the first partition member 16 is formed on the inner peripheral surface of the upper metal fitting 6b by the coating portion 8a of the rubber elastic body 6.
Are in close contact with each other.

On the outer peripheral surface of the first partitioning member 16, a groove 24 is formed in a substantially spiral shape so as to make substantially two rounds on the outer peripheral surface. One end of the groove 24 communicates with the main liquid chamber 18 at the end of the first partition member 16 on the power unit side, and the other end has the end of the groove 24 on the vehicle body side of the first partition member 16. It communicates with one sub liquid chamber 20.

That is, the first groove is formed by the groove 24.
A first orifice passage 26 is formed between the outer peripheral surface of the partition member 16 and the inner peripheral surface of the upper fitting 6b to communicate the main liquid chamber 18 and the first sub liquid chamber 20.

The inner diameter of the first partitioning member 16 at the end on the vehicle body side is reduced in a substantially stepwise manner over the entire circumference. The reduced diameter portion 28 has an annular groove 3 that opens toward the end of the first partition member 16 on the power unit side.
0 is formed over the entire circumference.

As shown in FIG. 2, inside the first partition member 16, a second partition member 32 made of metal and having a substantially bottomed cylindrical shape is provided.
Is press-fitted. The second partition member 32 is press-fitted so that the bottomed end 34 is located on the main liquid chamber 18 side and the open end 36 is located on the first sub liquid chamber 20 side.

The second partition member 32 is connected to the bottomed end portion 3.
The outer peripheral surface near 4 is a press-fit surface 38, and the outer diameter on the side of the opening end 36 is formed smaller than the outer diameter near the bottomed end 34. That is, the second partition member 3
The outer diameter of the second opening end 36 side is set smaller than the inner diameter of the vehicle-side end of the first partitioning member 16, and the outer peripheral surface of the opening end 36 is the inner circumference of the first partitioning member 16. Slightly spaced from the surface.

The bottomed end portion 34 is formed with a flange-like flange portion 40 that is in contact with the end surface of the first partition member 16 on the power unit side over the entire circumference. The press-fit surface 38 has a predetermined length along the axial direction of the second partition member 32.

Between the inner peripheral surface of the first partition member 16 at the end on the vehicle body side and the open end 36 of the second partition member 32, a rubber-made second diaphragm 42 having a substantially disk shape is provided. Are clamped and fixed. The second diaphragm 42 is connected to the first diaphragm 42
The outer peripheral edge is engaged with the annular groove 30 of the partition member 16, and by pressing the second partition member 32 into the first partition member 16, the reduced diameter portion 28 of the first partition member 16 and the second It is clamped and fixed to the opening end 36 of the two partition members 32. Further, the opening end 36 of the second partition member 32 and the first partition member 16 are formed by the second diaphragm 42.
Is sealed with the reduced-diameter portion 28.

The second diaphragm 42 and the bottomed end 34 of the second partition member 32 have the second
A second sub-liquid chamber 44 is defined adjacent to the first sub-liquid chamber 20 via a diaphragm 42.

On the outer peripheral surface of the second partitioning member 32, a groove 46 having a length substantially making a full circle around the outer peripheral surface is formed. One end of the second orifice passage 48 formed by the groove 46 and the inner peripheral surface of the first partition member 16 communicates with the main liquid chamber 18, and the other end thereof communicates with the second sub liquid chamber 44.
Is in communication with

The length of the first orifice passage 26 is formed to be longer than the length of the second orifice passage 48. The cross-sectional area of the first orifice passage 26 is set smaller than the cross-sectional area of the second orifice passage 48.

The bottomed end 34 of the second partition member 32 is integrally provided with a projection 50 projecting toward the main liquid chamber 18 as shown in FIG.

The protruding portion 50 has a substantially disk-shaped head 52 at the tip thereof and a columnar base 54 connected to a substantially center of the bottomed end 34, and has a substantially T-shaped cross section. Has a substantially umbrella shape as a whole.

The head 52 has an outer diameter of the main liquid chamber 1.
8 and smaller than the inner diameter of the head 5.
2 are arranged so that the radial direction is orthogonal to the vibration input direction, that is, the vertical direction in FIG. The head 52 is spaced apart from the rubber elastic body 8 by a predetermined distance, and is formed such that its outer peripheral edge 52a is close to the rubber elastic body 8 over the entire circumference. ing.

The base portion 54 is formed to have a smaller diameter than the head portion 52, and the main liquid chamber 1 of the second orifice passage 48 is formed.
The opening to 8 is formed so as not to be closed.

The first orifice passage 26 reduces the shake vibration generated in the frequency region around 10 Hz by the resonance action of the liquid flowing between the main liquid chamber 18 and the first sub liquid chamber 20. The dimensions of each part are set. Further, the second orifice passage 48 is connected to the main liquid chamber 18.
The dimensions of each part are set so that idle vibration generated in a frequency range around 20 to 30 Hz is reduced by the resonance action of the liquid flowing between the second sub liquid chamber 44 and the second sub liquid chamber 44.

The projections 50 provided on the second partition member 32 reduce vibrations in the frequency range of 100 Hz or more such as muffled sounds. More specifically, referring to FIG. 4, with the relative displacement of the projection 50 in the main liquid chamber 18 at the time of vibration input, the outer peripheral edge 5
The liquid flows between 2a and the rubber elastic body 8, and the resonance such as the flow of the liquid reduces vibration such as muffled sound. Here, FIG. 4 shows the liquid filled type vibration damping device 2 in a state where the mounting member 4 is mounted on a power unit such as an engine and the mounting member 6 is mounted on a vehicle body.

In the liquid-filled type vibration damping device 2 configured as described above, the number of components capable of reducing shake vibration and idle vibration can be reduced, and vibration such as muffled sound generated in a high frequency range can be reduced. Can be.

That is, by providing the projections 50 integrally with the second partition member 32, vibrations in three different frequency ranges such as shake vibration, idle vibration, and muffled sound can be reduced with a small number of parts. Therefore, the manufacturing cost can be reduced.

Since the second diaphragm 42 is held and fixed by the first partition member 16 and the second partition member 32, the first partition member 16 or the second partition member 32 is fixed.
The second diaphragm 42 does not need to be vulcanized and bonded, and since the projection 50 is formed integrally with the second partition member, the corresponding vulcanization bonding step and assembling step can be omitted. In addition, the projecting portion formed integrally with the second partition member can reduce the manufacturing cost.
It is not limited to the shape of the embodiment described above, and the liquid in the main liquid chamber is caused to flow with the relative displacement of the projections in the main liquid chamber at the time of vibration input. Any shape that can reduce vibration in the frequency domain may be used.

[0037]

According to the present invention, vibrations such as a muffled sound generated in a frequency region of 100 Hz or more due to the resonance action of the liquid flowing between the protrusion provided on the second partition member and the rubber elastic body are produced. Reduced. That is, the liquid-filled type vibration damping device that reduces vibrations in three different frequency ranges such as shake vibration, idle vibration, and vibration such as muffled sound is provided by integrally providing the protrusion to the second partition member.
Since it can be configured with a small number of parts, manufacturing costs can be reduced.

Further, the second diaphragm is sandwiched and fixed between the first partition member and the second partition member so that the second diaphragm is fixed.
The step of vulcanizing and bonding the diaphragm to the first partition member or the second partition member can be omitted, and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a liquid filled type vibration damping device according to the present invention.

FIG. 2 is an exploded sectional view of a first partition member, a second partition member, and a second diaphragm.

FIG. 3 is a front view of a second partition member.

FIG. 4 is a cross-sectional view of the liquid filled type vibration damping device according to the present invention in a state where the device is mounted on a vehicle.

FIG. 5 is a cross-sectional view of a conventional liquid-filled type vibration damping device.

[Explanation of symbols]

 16 First partition member 32 Second partition member 42 Second diaphragm 50 Projection 52 Head 54 Base

Claims (1)

[Claims] 1. A power unit-side mounting member and a vehicle body-side mounting member which are arranged to face each other, a rubber elastic body connecting the pair of mounting members to each other, and fixed to one of the pair of mounting members. A first diaphragm that forms a liquid chamber with the rubber elastic body; a first diaphragm that is disposed in the liquid chamber and is fixed to one of the pair of mounting members; A first partition member that defines a main liquid chamber on the body side and a first sub liquid chamber on the first diaphragm side; and a first protrusion protruding toward the main liquid chamber.
A second partition member press-fitted into the partition member, a second diaphragm sandwiched and fixed by the first partition member and the second partition member, and sealing between the first partition member and the second partition member; A second sub-liquid chamber defined by the second diaphragm and the second partition member and located inside the first partition member; and a second sub-liquid chamber communicating with the main liquid chamber and the first sub-liquid chamber. A first orifice passage, a second orifice passage formed between an inner peripheral surface of the first partition member and an outer peripheral surface of the second partition member, and communicating the main liquid chamber and the second sub liquid chamber. Wherein the tip of the projection is opposed to the rubber elastic body at a predetermined interval.