JP2003004091A - Liquid sealed vibration isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occurrence of an unusual noise by blocking the sudden variation of internal pressure of the main liquid chamber. SOLUTION: A partition member 12 is formed in a three layer structure which comprises the resin made upper part 22, the middle part 23 made of an elastic material and the lower part 24 made of metal or the like. An outer peripheral part of the upper part 22 is overlaid on a cushion flange 33. The outer peripheral part of the lower part 24 is abutted to the lower surface of a cushion flange 33. The lower surface of the outer peripheral part of the lower part 24 is overlaid on an elastic peripheral wall 37. By so doing, while the outer peripheral part of the partition member 12 is floated and supported through the cushion flange 33 and the elastic peripheral wall 37, the lower side 24 is vertically moved by the variation of internal pressure of the main liquid chamber 13, whereby blocking the sudden variation of internal pressure of the main liquid chamber 13. The top of a coil spring 48 in a press member 21 is floated and supported by an elastic material pressing part 41, thereby reducing vibration transmission from the coil spring 48 to the metal plate 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-sealing vibration isolator used for automobile engine mounts and the like.

[0002]

2. Description of the Related Art As such a liquid-sealed engine mount, an idle orifice passage is provided between a main liquid chamber and a sub-liquid chamber, and a part of a diaphragm constituting the sub-liquid chamber is used as a seating portion. While opening and closing, the pressing member normally presses the seat to close the opening of the idle orifice passage, and the pressing member opens the seat during idling. With K, the seat opens the opening of the idle orifice passage. It has been known that the idle orifice passage is opened (see Japanese Patent Laid-Open No. 10-281214 as an example).

[0003]

When the opening / closing means for the orifice passage is provided as described above, the opening / closing means may generate an abnormal noise. For example, in the case of the above idle orifice passage, when a large vibration is input at the time of starting or stopping the engine in a closed state, the elastic main body is largely elastically deformed to positively or negatively pressure the main liquid chamber. As a result, a sudden change in internal pressure may occur, and a large number of air bubbles may be generated in the liquid, causing a cavitation phenomenon in which air is generated. When this phenomenon occurs, the opening / closing means that closes the orifice passage is pushed toward the side of the sub-liquid chamber or, conversely, strongly adsorbed to the side of the main liquid chamber. By repeating this, the abnormal noise is generated. . Therefore, an object of the present invention is to prevent abnormal noise from being generated by the opening / closing means based on the internal pressure fluctuation of the main liquid chamber when the engine is started or stopped.

[0004]

In order to solve the above-mentioned problems, a first invention relating to a liquid-sealing vibration isolator according to the present invention is a first mounting member mounted on a vibration source side and a second mounting member mounted on a vehicle body side. And a substantially conical elastic main body provided between them, forming a liquid chamber having the elastic main body as a part of a wall, and partitioning the liquid chamber with a main liquid chamber. In a liquid sealing and vibration isolating device, which is divided into a sub liquid chamber by a partition member, an orifice passage communicating between the main liquid chamber and the sub liquid chamber is formed in the partition member, and an opening / closing means for opening and closing the orifice passage is provided. The outer peripheral portion of the partition member is floatingly supported via an elastic member.

According to a second aspect of the invention, on the same premise as described above, a seating portion provided on a diaphragm forming a sub liquid chamber and a pressing member for pressing the same by a return spring are provided as opening and closing means for the orifice passage. The pressing member is made of an elastic material in which a rigid plate is integrated to support one end of the return spring in a floating manner.

[0006]

According to the first aspect of the present invention, since the outer peripheral portion of the partition member is floatingly supported by supporting the partition member via the elastic member, there is a large vibration input associated with, for example, starting or stopping the engine. And the internal pressure fluctuation is absorbed by the movement of the partition member in accordance with the internal pressure fluctuation of the main liquid chamber. Therefore, it is possible to suppress a sudden change in the internal pressure of the main liquid chamber and prevent the occurrence of a cavitation phenomenon, so that the generation of abnormal noise can be reduced.

According to the second aspect of the invention, since the return spring of the pressing member is supported in a floating manner, the force input from the return spring to the rigid plate forming the pressing member is reduced, and as a result, the plate is different. Even if sound is generated, it can be reduced. The same applies to the input from the return spring to the plate when the return spring resonates.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment will be described below with reference to the drawings. FIG. 1 is a full sectional view of a liquid-sealed engine mount according to this embodiment, FIG. 2 is an exploded view of constituent members, FIG. 3 is an enlarged sectional view showing a fixing portion structure of a partition member, and FIG. 4 is an enlarged sectional view of a pressing member. Is. In the following description, the upper, lower, left and right sides of the liquid seal vibration isolator will be expressed with reference to the state of FIG.

First, in FIGS. 1 and 2, this engine mount has a first mounting member 1, a second mounting member 2 and an elastic main body portion 3, and the first mounting member 1 is a vibration source by a screw. Is attached to the engine which is the second attachment member 2
Is attached to the vehicle body by the flange 4.

The flange 4 is connected to a metal operating chamber cylinder 6 surrounding the opening / closing means chamber 5, and its upper end is connected to the main liquid chamber cylinder 7 by caulking. The main liquid chamber cylinder portion 7 is integrated with the hem portion of the elastic main body portion 3, and a lining portion 8 that is continuously and integrally formed with the elastic main body portion 3 is formed on the inner surface thereof.

A circular hole 9 is partly formed on the side surface of the main liquid chamber cylinder portion 7. The lining portion 8 of this hole 9 portion has a lateral membrane portion 10 which is elastically deformable inward and outward through the hole 9. Eggplant The transverse membrane portion 10 is for absorbing the internal pressure fluctuation of the main liquid chamber 13, and the elastic deformation of the transverse membrane portion 10 may be controlled by an operating means such as a solenoid if necessary.

A liquid chamber is formed in a space surrounded by the first mounting member 1, the second mounting member 2 and the elastic main body 3, and the interior thereof is divided by the partition member 12 into the main liquid chamber on the elastic main body 3 side. 1
3 and the auxiliary liquid chamber 14 on the opening / closing means chamber 5 side. The sub liquid chamber 14 is formed between the diaphragm 15 and the partition member 12 in the opening / closing means chamber 5.

A non-compressible liquid is sealed in the liquid chamber, and the main liquid chamber 13 is in constant communication with the sub liquid chamber 14 and a damping orifice passage 16 and an openable / closable idle orifice passage 1 are provided.
You will be contacted with 7. An opening 18 of the idle orifice passage 17 on the side of the sub liquid chamber 14 is opened and closed by a thick seat portion 20 formed in the central portion of the diaphragm 15, and the seat portion 20 is opened by the pressing member 21 in the partition member 12.
It is controlled so that the opening 18 is closed by being pressed against the surroundings and brought into close contact, and conversely, by pulling down the pressing member 21, the opening 18 is opened apart from the partition member 12.

As is apparent from FIG. 2, the partition member 12
Is a circular table-shaped upper portion 22 made of resin that largely projects into the main liquid chamber 13, an intermediate portion 23 made of an elastic member such as rubber, and a metallic lower portion 24 made of aluminum die casting or the like.
Is a combination of.

A flange 25 is formed on the outer peripheral portion of the upper portion 22, a ceiling portion 26 forming a part of the damping orifice passage 16 is formed on a part of the flange 25, and a fixed portion 27 is formed on the outermost peripheral portion. Further, a substantially spiral passage 28 opened downward is formed in the central portion, and one end thereof communicates with the opening 18 and the other end communicates with the main liquid chamber 13.

The intermediate portion 23 is provided with a tapered portion 30 which gradually becomes thicker toward the outer peripheral side and a concave groove 31 formed on the outer peripheral side thereof, and the outermost peripheral portion is a standing wall 32 which is an outer wall of the concave groove 31. The recessed groove 31 faces the ceiling portion 26 and is assembled to form an upper portion of the damping orifice passage 16 inside. The upper end of the standing wall 32 is a cushion flange 33 that projects radially outward.

The damping orifice passage 16 is spirally formed between the upper portion 22 and the intermediate portion 23 and between the intermediate portion 23 and the lower portion 24, and one end of the damping orifice passage 16 communicates with the main liquid chamber 13.
The other end communicates with the sub liquid chamber 14. This characteristic is set so as to resonate with the liquid column with respect to low-frequency vibration during one-step traveling.

Of the contact portion between the upper portion 22 and the intermediate portion 23, the inner portion facing the damping orifice passage 16 is a tapered joint portion 29 (FIG. 1). Further, the fixing portion 27 overlaps the cushion flange 33 of the standing wall 32.

An opening 18 is formed in the center of the lower portion 24,
A groove 34 is formed below the groove 31, and a lower part of the damping orifice passage 16 is formed between the groove 34 and the intermediate portion 23. The outermost peripheral portion of the intermediate portion 23 forms a standing wall 35 and overlaps the outside of the standing wall 32, and its upper end abuts the lower surface of the cushion flange 33.

The diaphragm 15 made of a suitable burnable material such as rubber is integrated with the mounting ring 36 having a substantially crank-shaped cross section on the outer peripheral portion thereof, and an elastic peripheral wall 37 extending upward along the inner surface thereof is formed. . The elastic peripheral wall 37 extends upward along the outside of the standing wall 35, and the outer peripheral end of the fixing portion 27 contacts the inner peripheral surface of the upper end portion. The upper end 38 of the mounting ring 36 is sandwiched between the working chamber tubular portion 6 and the main liquid chamber tubular portion 7 and integrally fixed by caulking.

As a result, the partition member 12 becomes the main liquid chamber cylindrical portion 7
Of the caulking flange 7a (FIG. 2) and the inward flange 39 (FIG. 2) formed at the lower end of the mounting ring 36, and the cushion flange 33 and the elastic peripheral wall 3 are fixed.
Floating supported by 7.

The pressing member 21 has a columnar shape with its central portion projecting upward and its peripheral portion spreading laterally. The pressing member 21 is entirely covered with a non-breathable burnable film 40, and its central portion is made of an elastic material such as rubber. The thick pressing portion 41 is integrated. Further, a metal plate 42 having one end integrated with the pressing portion 41 is provided along the inside of the burnable film 40, and the other end of the outer periphery thereof is the thick end portion 43 which is the outer periphery of the burnable film 40. It is integrated with.

The circumference of the thick end portion 43 is caulked integrally with the outer circumference of the resin bottom plate 45 by a fixing ring 44. As a result, a closed space is formed between the burnable film 40 and the bottom plate 44 to form the negative pressure chamber 46.
In addition, a joint pipe 47 for connecting the negative pressure chamber 46 and an intake passage of the engine (not shown) is formed in the center of the bottom plate 44.

A coil spring 48 is provided between the periphery of the joint pipe 47 and the pressing portion 41. When the negative pressure chamber 46 is opened to the atmosphere, the pressing portion 41 is pushed up to lower the seating portion 20 to the lower portion 24. When the negative pressure is connected to the seat 18 by pressing the seat 18 around the opening 18, the seating portion 20 opens the seat 18 against the coil spring 48. Reference numeral 49 is a recess provided on the surface of the pressing member 21 that contacts the seat 20.

As shown in FIG. 3, the partition member 12 is supported between the working chamber cylinder 6 and the main liquid chamber cylinder 7 through the cushion flange 33 and the elastic peripheral wall 37 so as to be floatingly supported. There is. That is, the flange 25, which is the outer peripheral portion of the upper portion 22, can be moved downward in the figure by the cushion flange 33 and the elastic peripheral wall 37, and the lower portion 24 has the outer peripheral side standing wall 35 in contact with the cushion flange 33 and the elastic peripheral wall 37 in the vertical direction. , Can be moved up and down in the figure.

Therefore, when + vibration is applied to the main liquid chamber 13, the cushion flange 33 and the elastic peripheral wall 37 are compressed and the partition member 12 as a whole moves downward in the figure, and the main liquid chamber 13
Prevents sudden changes in internal pressure. On the contrary-when vibration is applied,
The lower portion 24 of the partition member 12 compresses the cushion flange 33 and moves to the upper side in the figure, and also prevents a sudden change in the internal pressure of the main liquid chamber 13. However, since the upper portion 22 of the partition member 12 is directly fixed to the upper side by the crimping flange 7a, the upward movement is restricted.

As shown in FIG. 4, the coil spring 48
The upper end of the abuts against the pressing portion 41. The pressing portion 41 is an elastic member, and the coil spring 48 is floatingly supported by the pressing portion 41. Therefore, the pressing member 21
When the force and the vibration are applied to the metal plate 42 from the coil spring 48 via the pressing portion 41, the force applied to the metal plate 42 at this time due to the floating support by the pressing portion 41. And the transmission of vibrations is greatly reduced.

On the other hand, the metal plate 42 is a substantially trumpet-shaped member having rigidity, and when vibration is transmitted to the metal plate 42, it functions as a kind of speaker. Therefore, the coil spring 48 is floatingly supported to reduce the transmission of vibrations to the metal plate 42, thereby reducing the generation of abnormal noise from the metal plate 42. Further, when the pressing member 21 and the seating portion 20 move up and down relatively violently, the coil spring 48 also resonates, but vibration transmission to the metal plate 42 at the time of this resonance is also reduced, and noise is similarly generated. To reduce.

[Brief description of drawings]

FIG. 1 is a full sectional view of an engine mount according to an embodiment.

[Fig. 2] Exploded view of essential parts

FIG. 3 is an enlarged sectional view showing a floating support structure of a partition member.

FIG. 4 is an enlarged sectional view showing a floating support structure of a return spring.

[Explanation of symbols]

1: 1st attachment member, 2: 2nd attachment member, 3: elastic main body part, 6: working chamber cylinder part, 7: main liquid chamber cylinder part, 10: lateral membrane part, 12: partition member, 13: Main liquid chamber, 14: Sub liquid chamber, 1
5: Internal pressure change, 16: Damping orifice passage, 1
7: idle orifice passage, 18: opening, 20: seating portion, 21: pressing member, 22: upper portion, 23: intermediate portion, 2
4: Lower part, 33; Cushion flange, 37: Elastic peripheral wall, 41: Pushing part, 42: Metal plate, 48: Coil spring

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Claims (2)

[Claims] 1. An elastic main body comprising a first mounting member mounted on the vibration source side, a second mounting member mounted on the vehicle body side, and a substantially conical elastic main body portion provided therebetween. Part of the wall is formed, and this liquid chamber is divided into a main liquid chamber and a sub liquid chamber by a partition member, and an orifice passage that connects these main liquid chamber and the sub liquid chamber is partitioned. A liquid-sealing anti-vibration device, which is formed on a member and has an opening / closing means for opening / closing the orifice passage, wherein the outer peripheral portion of the partition member is floating-supported via an elastic member. Shaking device. 2. A first attachment member attached to the vibration source side, a second attachment member attached to the vehicle body side, and a substantially conical elastic main body portion provided therebetween, and the elastic main body. Part of the wall is formed, and this liquid chamber is divided into a main liquid chamber and a sub liquid chamber by a partition member, and an orifice passage that connects these main liquid chamber and the sub liquid chamber is partitioned. A liquid seal vibration isolator formed on a member and provided with opening / closing means for opening / closing the orifice passage, and a seating portion provided on a diaphragm forming the sub-liquid chamber as opening / closing means for the orifice passage, and Is provided with a pressing member for pressing the return spring, and the pressing member is made of an elastic material in which a rigid plate is integrated to support one end of the return spring in a floating manner. Anti-vibration device for liquid seal.