JP2003004086A - Liquid sealed vibration isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an unusual noise associated with a sudden internal pressure change in a main liquid chamber. SOLUTION: A partition member partitioning a main liquid chamber and an auxiliary liquid room is provided with an idle orifice passage whose opening is opened and closed by a seat part 20 provided to a part of a diaphragm 15, wherein the opening/closing is controlled by a press member. The seat part 20 is thickend, and recesses 51 and 52 are provided on the upper and lower sides. A hemispherical projection 54 and a seal having a sectional shape having an approximately right triangle around the seat part 20 provided with a thin wall part 53 are provided around the seat part 20. The horizontal film part is provided to the side in elastic body 3.

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. In addition to opening and closing, normally, the pressing member pushes the seat to close the opening of the idle orifice passage, and when the seat is idle, the pressing member opens the seat, so that the seat opens the opening of the idle orifice passage. A configuration is known in which the idle orifice passage is opened (for example, see JP-A-10-281214).

[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 suppress the generation of abnormal noise 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, the first aspect of the present invention relating to the liquid-sealing vibration isolator comprises: a first attachment member attached to the vibration source side; and a second attachment member attached to the 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 the 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. In the opening / closing means, a seating portion that comes into contact with the opening of the orifice passage is formed of at least an elastic member and is thicker than other portions,
It is characterized in that a thin-walled portion is provided at the center of the seating portion so as to absorb fluctuations in the internal pressure of the main liquid chamber.

According to a second aspect of the present invention, in the above-mentioned first aspect, an annular seal is formed around the thin portion of the seating portion, and the cross section of the seal is oblique to the inside of the seating portion and substantially perpendicular to the outside. It is characterized in that it is formed into a substantially right-angled triangular shape having sides.

A third aspect of the present invention is characterized in that, in the second aspect, a plurality of substantially hemispherical protrusions having a lower protrusion height inside the seal are formed in the circumferential direction.

A fourth aspect of the present invention is characterized in that, in any one of the first to third aspects, the seating portion is formed on a part of a diaphragm forming a sub liquid chamber.

According to a fifth aspect of the present invention, in the fourth aspect, the orifice passage is closed by pressing the seat with a pressing member, and a recess is formed on the side of the seat that contacts the pressing member. Characterize.

According to a sixth aspect of the present invention, in the fifth aspect, a concave portion is provided on a surface of the pressing member that comes into contact with the seat portion.

According to a seventh aspect of the present invention, in the elastic body portion according to any one of the first to sixth aspects, a thin transverse membrane portion that is elastically deformable and detachable is provided, and the transverse membrane portion absorbs a change in internal pressure in the main liquid chamber. It is characterized by having done.

[0011]

According to the first aspect of the present invention, since the seat portion is formed thick and the central portion thereof is made thin, the thin portion absorbs fluctuations in the internal pressure of the main liquid chamber. Therefore, even if a large vibration is input, a sudden change in the internal pressure of the main liquid chamber is suppressed to suppress the occurrence of a cavitation phenomenon, so that abnormal noise due to the seating portion is less likely to occur.

According to the second aspect, since the seal has a substantially right-angled triangular cross section and the outside is a substantially vertical side, when the seating portion abuts on the partition member side, the apex of the seal that abuts first is Since it falls to the vertical side, it enhances the sealing effect and reduces the impact to suppress the generation of abnormal noise.

According to the third aspect of the present invention, since the substantially hemispherical protrusion having a lower protruding height than that of the seal is provided, the seal is brought into contact with the low spring first, and then the protrusion of the higher spring is brought into contact with the seal. Can be changed, and the spring of the opening / closing means can be changed non-linearly at the time of contact with the partition member.

According to the fourth aspect, since the seat portion is formed by a part of the diaphragm, the seat portion having each of the above structures can be easily provided.

According to the present invention, since the pressing member is provided and the recess is provided on the side of the seating portion where the pressing member abuts, the impact at the time of contact between the pressing member and the seating portion is alleviated and abnormal noise is generated. Can be suppressed.

According to the sixth aspect, since the concave portion is provided on the surface of the pressing member that comes into contact with the seat portion, the impact when the pressing member abuts on the seat portion is mitigated, and the generation of abnormal noise is suppressed.

According to the present invention, since the transverse membrane portion is provided on the elastic main body portion, when the internal pressure of the main liquid chamber increases, the transverse membrane portion deforms and absorbs the internal pressure. Therefore, the internal pressure fluctuation transmitted to the opening / closing means. The influence of is reduced, and the generation of abnormal noise is suppressed.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment will be described below with reference to the drawings. 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 of a seat portion, FIG. 4 is a plan view of the seat portion, and FIG. 5 is a seal. FIG. 6 is an enlarged view of a portion, and FIG. 6 is a plan view of the pressing member. In the following description, up, down, left and right 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 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 which surrounds 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 partially formed on the side surface of the main liquid chamber cylinder 7.
The lining portion 8 of the hole 9 forms a lateral film portion 10 which is elastically deformable outward through the hole 9. 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 main liquid chamber 13, and is connected to the auxiliary liquid chamber 14 through a damping orifice passage 16 and an openable / closable idle orifice passage 17. Sub liquid chamber 14 of idle orifice passage 17
The side opening 18 is formed in the central portion of the diaphragm 15,
It is opened and closed by a thick-walled seating portion 20, and the seating portion 20 is controlled by the pressing member 21 to be in close contact with the partition member 12 or to open the opening 18.

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

A flange 25 is formed on the outer peripheral portion of the upper portion 22, a part thereof is a recessed portion 26 forming the damping orifice passage 16, and a outermost peripheral portion is a fixed portion 27. 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 taper 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 concave groove 31 is combined with the concave portion 26 so as to face each other, and forms 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 the upper end thereof abuts the lower surface of the cushion flange 33.

The diaphragm 15 made of an appropriately calcinable material such as rubber has an outer peripheral portion integrated with a mounting ring 36 having a substantially crank-shaped cross section, forms an elastic peripheral wall 37 extending upward along the inner surface thereof, and a standing wall 35. The mounting ring 3 extends upward along the outer side of the mounting portion and is in contact with the outer peripheral end of the fixing portion 27.
The upper end 38 of 6 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 center protruding upward and its periphery spreading laterally. The pressing member 21 is entirely covered with a non-breathable burnable film 40, and its center is made of an elastic material such as rubber. A thick pressing portion 41 is integrally formed.

A metal plate 42, one end of which is 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 outer periphery of the burnable film 40. Part 4
It is integrated with 3.

The periphery of the thick end portion 43 is caulked integrally with the outer peripheral portion and the entire periphery of the resin bottom plate 45 by the fixing ring 44. As a result, a closed space is formed between the burnable film 40 and the bottom plate 44 to form a negative pressure chamber 46, and the negative pressure chamber 4 is provided at the center of the bottom plate 44.
A joint pipe 47 is formed to connect 6 to the intake passage of the engine (not shown).

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.

FIG. 6 is a plan view showing the pressing member 21 from above in FIG. 2, and as is apparent from this drawing, the pressing member 2 is shown.
A circular concave portion 49 is formed in the center of the upper surface that contacts the seating portion 20 of No. 1.
Is provided. The circular concave portion 49 reaches the outer peripheral portion and communicates with the open cross-shaped groove 49a.

As shown in FIGS. 3 to 5, the seating portion 20 is formed with a ring-shaped portion 50 which is thicker than the other portions, and central portions are formed with concave portions 51 and 52 on the front and back surfaces. 5
A thin portion 53 is formed by 1, 52.

In the ring-shaped portion 50, substantially hemispherical projections 54 are formed concentrically on the inner peripheral side at predetermined intervals, and a seal 55 having a substantially right-angled triangular cross section is formed on the outer peripheral side. Protrusion 54
The protrusion height of is lower than that of the seal 55 by d (FIG. 5).

The seal 55 has a slanted side 56 on the inner side, a vertical side 57 on the outer side, and a vertex 58 on or substantially near the extension of the vertical side 57.

Next, the operation of this embodiment will be described. When a large vibration is generated at the time of starting and stopping the engine, it is transmitted to the engine mount, the elastic main body portion 3 is largely deformed, and the internal pressure fluctuation in the main liquid chamber 13 occurs. At this time, when the elastic body portion 3 is deformed downward, the idle orifice passage 1
Due to the large hydraulic pressure applied to the opening 18 from inside 7, the seat 20
The pressing member 21 is pushed down, and the opening 18 of the lower portion 24
Stay away from the surroundings. On the contrary, when the elastic main body 3 is deformed upward, the inside of the main liquid chamber 13 becomes a negative pressure, and the seating portion 20 moves downward.
Is sucked and adhered to the vicinity of the opening 18.

At this time, since the seat portion 20 is formed thick and the central portion thereof is the thin portion 53, the thin portion 53 absorbs the fluctuation of the internal pressure of the main liquid chamber 13. Therefore, even if a large vibration is input, a sudden change in the internal pressure of the main liquid chamber 13 is suppressed to suppress the occurrence of a cavitation phenomenon.
An abnormal noise due to 0 is less likely to occur.

Further, since the seal 55 has a substantially right-angled triangular cross section and the outside has a substantially vertical side 57, when the seating portion 20 abuts on the partition member side, as shown by phantom lines in FIG.
First, the apex of the seal 55 that comes into contact first falls to the side of the vertical side 57, so that the sealing effect is enhanced and the impact is mitigated to suppress the generation of abnormal noise.

Further, since the substantially hemispherical projection 54 having a lower protruding height than the seal 55 is provided, the contact state is set so that the seal 55 first abuts with the low spring and then the projection 54 of the higher spring abuts. Partition member 12 that can be changed
The spring of the opening / closing means can be changed non-linearly at the time of contact with.

In addition, the seat 20 is attached to the diaphragm 15
The seating portion 20 can be easily provided because it is configured by a part of the seat.

Further, since the pressing member 21 is provided and the concave portion 52 is provided on the side of the seating portion 20 on which the pressing member 21 abuts, the impact at the time of contact between the pressing member 21 and the seating portion 20 is alleviated and abnormal noise is generated. Occurrence can be suppressed.

Moreover, since the circular recess 49 is provided on the surface of the pressing member 21 that comes into contact with the seating portion, the pressing member 21 is made a low spring to reduce the impact when the pressing member 21 comes into contact with the seating portion 20, and Suppress the generation of sound.

[Brief description of drawings]

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

[Figure 2] Exploded view of the main part

FIG. 3 is an enlarged sectional view of a seat portion.

FIG. 4 is a plan view thereof

FIG. 5 is an enlarged sectional view of a seal part.

FIG. 6 is a plan view of a pressing member.

[Description of Reference Signs] 1: First mounting member, 2: Second mounting member, 3: Elastic main body portion, 10: Transverse membrane portion, 12: Partition member, 13: Main liquid chamber, 14: Sub liquid chamber, 15: change in internal pressure, 16: damping orifice passage, 17: idle orifice passage, 1
8: Opening, 20: Seating portion, 21: Pressing member, 51: Recessed portion, 52: Recessed portion, 53; Thin portion, 54: Protrusion, 55: Seal

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Komitsu Southern             1239 Kamekubo, Oimachi, Iruma-gun, Saitama             Yamashita Rubber Co., Ltd. F-term (reference) 3D035 CA05 CA35                 3J047 AA03 CA09 CB06 DA02 FA02

Claims (7)

[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 to form a liquid chamber, this liquid chamber is partitioned by a partition member into a main liquid chamber and a sub liquid chamber, and an orifice passage that connects these main liquid chamber and sub liquid chamber is partitioned. In the liquid seal vibration isolator, which is formed on a member and is provided with an opening / closing means for opening / closing the orifice passage, the opening / closing means has at least a seating portion which is in contact with the opening of the orifice passage and is made of an elastic member. The liquid sealing and vibration isolating device is characterized in that it is formed thicker than the above portion, and that a thin portion is provided in the central portion of this seating portion to absorb fluctuations in the internal pressure of the main liquid chamber. 2. A ring-shaped seal is formed around a thin portion of the seat, and the cross section of the seal has a substantially right-angled triangular shape having an oblique side inside the seat and a side substantially perpendicular to the outside. The liquid seal vibration proof device according to claim 1, wherein the liquid seal vibration proof device is formed so as to form an eggplant. 3. The liquid-sealing vibration isolator according to claim 2, wherein a plurality of substantially hemispherical projections having a lower projecting height inside the seal are formed in the circumferential direction. 4. The liquid-sealing vibration isolator according to claim 1, wherein the seating portion is formed on a part of a diaphragm forming a sub liquid chamber. 5. The orifice passage is closed by pressing the seat with a pressing member, and a recess is formed on the side of the seat that contacts the pressing member. Liquid seal anti-vibration device. 6. The liquid seal vibration isolator according to claim 5, wherein a recess is provided on a surface of the pressing member that comes into contact with the seating portion. 7. The elastic main body is provided with a thin transverse membrane portion that is elastically deformable and detachable, and the transverse membrane portion absorbs a change in internal pressure in the main liquid chamber.
The liquid-sealing vibration isolator according to any one of 1.