JP2000310274A - Fluid-sealed type vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a vibration control characteristic along a wider frequency region by securing tuning freedom of first and second orifice passages and adding a hydraulic pressure absorption mechanism, capable of displaying an effective vibration control effect against vibration of a high frequency region with superior space efficiency. SOLUTION: This device is constituted by forming a first orifice passage 48, tuned to a low frequency region on the outer peripheral part of a partition member 30 and forming a second orifice passage 52 tuned to an intermediate frequency region in length less than one cycle in the circumferential direction at an intermediate part in the diametrical direction of the partition member 30. A movable plate 56, constituting a hydraulic pressure absorption mechanism, is arranged in a region of an intermediate part in the diametrical direction of the partition member 30 on which the second orifice passage 52 is not formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid-filled type vibration damping device which obtains a vibration damping effect based on a flow action such as a resonance action of a sealed incompressible fluid, and more particularly to vibrations in different frequency ranges. By selectively using the first and second orifice passages tuned to exhibit an effective anti-vibration effect, a fluid-filled type anti-vibration that can obtain an anti-vibration effect according to the input vibration The present invention relates to a vibration device.

[0002]

2. Description of the Related Art Conventionally, as a kind of a vibration isolator, by selectively using first and second orifice passages which are tuned differently from each other, the flow action and pressure fluctuation of a fluid sealed inside are selectively performed. 2. Description of the Related Art There is known a fluid-filled type vibration damping device that can change and adjust a vibration damping effect obtained by utilizing the above-described method according to input vibration or the like. As described in JP-A-8-270718, JP-A-9-280304, and the like, such a vibration isolating device generally includes a first mounting bracket formed by a second mounting having a substantially cylindrical shape. The first mounting bracket and the second mounting bracket are connected to each other by an elastic body of the main body, and are disposed separately on one axial side of the opening in the axial direction. The opening is fluid-tightly covered, and the other opening in the axial direction of the second mounting member is fluid-tightly covered with a flexible film. Further, a partition is formed between the rubber elastic body and the flexible film. A pressure receiving chamber in which vibration is input between the partition member and the opposing surfaces of the main rubber elastic body is formed by disposing a member and fixedly supported by the second mounting bracket. A variable-capacity equilibrium chamber is formed between the pressure receiving chamber and the flexible membrane. A first orifice passage communicating with the first orifice passage and a second orifice passage tuned to a higher frequency range than the first orifice passage are formed in the partition members, respectively, while the flexible membrane is interposed therebetween. An actuator is disposed on the opposite side of the equilibrium chamber, and the flexible membrane is axially displaced by the actuator so as to abut / separate from the opening of the second orifice passage in the partition member. The second orifice passage is cut off / communicated to control the vibration isolation characteristics.

[0003] In such a conventional fluid-filled type vibration damping device, in the tuning frequency range of the first and second orifice passages, the vibration damping effect based on the flow action of the fluid caused to flow through those orifice passages is not obtained. Effectively, when vibration is input in a frequency range higher than the tuning frequency range of the second orifice passage, the fluid flow resistance of any of the orifice passages is significantly increased, and the vibration isolation characteristics tend to be significantly reduced. there were. for that reason,
Further improvement has been desired in cases where vibration isolation characteristics are required in a wider frequency range, particularly in a high frequency range.

[0004] In order to cope with such a demand, for example, a movable plate that can be minutely displaced based on the pressure difference between the pressure receiving chamber and the equilibrium chamber is provided in the partition member, and the pressure of the pressure receiving chamber during the input of high-frequency vibration is increased. By providing a hydraulic pressure absorbing mechanism that absorbs and reduces the fluctuation by the displacement of the movable plate, it is conceivable to reduce the dynamic spring in a high frequency range. However, when a movable plate is further arranged on the partition member in which the first orifice passage and the second orifice passage are formed, it is difficult to avoid an increase in the size of the partition member and complexity of the structure. A big issue is how to secure the installation space. In particular, depending on the arrangement position of the movable plate in the partition member, the degree of freedom in tuning the first and second orifice passages such as the passage cross-sectional area and the passage length may be limited. The displacement position of the flexible film that is brought into contact with / separated from the opening of the orifice passage is also limited, and depending on the displacement position of the flexible film, the durability and the displacement of the flexible film are reduced. Significant adverse effects can also occur.

[0005]

The present invention has been made in view of the above-mentioned circumstances, and has as its object to solve the problem of the degree of freedom of tuning the first and second orifice passages and the flexibility of the orifice passage. Space for the movable plate in the partition member can be efficiently obtained while ensuring sufficient durability of the conductive film, thereby exhibiting an excellent anti-vibration effect against vibration in a wider frequency range. It is an object of the present invention to provide a fluid filled type vibration damping device.

[0006]

An embodiment of the present invention which has been made to solve such a problem will be described below. In addition, each aspect described below can be adopted in any combination. In addition, it should be understood that aspects and technical features of the present invention are not limited to those described below, but are recognized based on the inventive concept described in the entire specification and the drawings. It is.

According to a first aspect of the present invention, a first mounting member is disposed at a distance from one of the openings in the axial direction of a second mounting member having a substantially cylindrical shape. The member and the second mounting member are connected by a rubber elastic body so as to cover one opening in the axial direction of the second mounting member in a fluid-tight manner and to open the other opening in the axial direction of the second mounting member. By covering the portion with a flexible film in a fluid-tight manner, further arranging a partition member between the main rubber elastic body and the flexible film and fixedly supporting the second mounting member, A pressure receiving chamber into which vibration is input is formed between the partition member and the opposing surface of the main rubber elastic body, and a variable-capacity equilibrium chamber is formed between the partition member and the flexible membrane. A first orifice passage that communicates with the balance chamber, and a tuner in a higher frequency range than the first orifice passage. And a second orifice passage formed in the partition member, and an actuator is disposed on the opposite side of the equilibrium chamber with the flexible film interposed therebetween. Is displaced to abut / separate from the opening of the second orifice passage in the partition member, thereby shutting off / communicating the second orifice passage. One orifice passage is formed so that the outer peripheral portion of the partition member extends in the circumferential direction, and the second orifice passage has a length less than one circumference in the circumferential direction at the radially intermediate portion of the partition member. And one end in the circumferential direction opens to the pressure receiving chamber side, and the other end in the circumferential direction extends radially inward and is formed so as to open to the equilibrium chamber side substantially at the center of the partition member. A movable plate in which the internal pressure of the pressure receiving chamber and the equilibrium chamber is applied to one surface of each of the second orifice passages at a radially intermediate portion of the cutting member is provided so as to be displaceable by a predetermined amount. I did it.

In the fluid filled type vibration damping device having the structure according to the first aspect, the first orifice passage is formed in the outer peripheral portion of the partition member, so that the passage length can be advantageously secured. The first orifice passage can be advantageously tuned to a low frequency range. In addition, since the second orifice passage is formed at the intermediate portion in the radial direction of the partition member, the second orifice passage can also advantageously secure a passage length necessary for tuning to the middle frequency range. Moreover, since the second orifice passage is opened toward the equilibrium chamber at the center of the partition member, the center of the flexible membrane can be displaced by the actuator to open and close the second orifice passage. Because it is possible, the durability of the flexible membrane is advantageously ensured, and even when the flexible membrane is in contact with the partition member, the volume of the equilibrium chamber can be changed by the outer peripheral portion of the flexible membrane. Can be secured advantageously, and the vibration-proof effect and the like by the first orifice passage can be effectively exhibited.
Furthermore, by using a space in the radially intermediate portion of the partition member where the second orifice passage is not formed, the movable plate is disposed, so that the movable member of an effective size can be suppressed while suppressing the enlargement of the partition member. A plate can be provided, and thereby, it is possible to effectively obtain an anti-vibration effect in a high frequency region based on a hydraulic pressure absorbing action of the pressure receiving chamber by the movable plate.

In this embodiment, a partition member made of a hard material such as metal or synthetic resin is preferably used. In addition, as the flexible film, a thin rubber film reinforced with canvas or the like, a resin film that is easily deformed, or the like is preferably employed as necessary. Further, any actuator may be used as long as it can reciprocate the flexible film.
For example, a pneumatic actuator having a closed air chamber and taking out displacement of a wall portion due to a change in air pressure of the air chamber as an output, and an output member capable of being displaced based on the action of electromagnetic force or magnetic force Any of an electromagnetic or electric actuator and the like can be adopted. Further, by fixing the output member of the actuator to the flexible film, it is possible to prevent the flexible film from being damaged due to rubbing between the output member of the actuator and the flexible film.

According to a second aspect of the present invention, there is provided a fluid filled type vibration damping device having a structure according to the first aspect,
It is an object of the present invention that the first orifice passage is formed by covering a circumferential groove that opens in the outer peripheral surface of the partition member and extends in the circumferential direction with the second mounting member. In this aspect, by forming the first orifice passage at the outermost peripheral portion of the partition member,
The length of the first orifice passage can be more advantageously secured. Further, by using the second mounting member, the first orifice passage can be formed with a simple structure.

According to a third aspect of the present invention, there is provided a fluid filled type vibration damping device having a structure according to the first or second aspect, wherein the second orifice passage is formed in one axial direction of the partition member. A lid member having a concave groove formed so as to extend in the circumferential direction at the middle portion in the radial direction and having one end portion in the circumferential direction extending radially inward and overlapping the partition member. On the other hand, a housing recess extending in the circumferential direction and opening on the same side as the groove is formed between the circumferential ends of the groove, and the movable plate is formed in the housing recess. The housing recess is covered with the lid member, and a communication hole communicating the housing recess with the pressure receiving chamber or the equilibrium chamber is formed in the bottom wall and the lid member of the housing recess. After being formed, the internal pressures of the pressure receiving chamber and the equilibrium chamber are adjusted on one surface of the movable plate. That it has to be exerted, it characterized. According to this aspect, in the partition member, the formation of the second orifice passage and the disposition of the movable plate include:
Either can be advantageously realized with a simple structure. In particular, a simple-shaped plate member or the like can be used as the lid member, which can further improve manufacturability and manufacturing cost. In this aspect, as the movable plate, a plate body not directly supported by the partition member may be disposed so as to be freely displaceable between the bottom wall of the housing recess and the facing surface of the lid member. However, for example, an elastically deformable rubber plate is disposed between the bottom wall of the housing recess and the lid member at the outer peripheral edge thereof, and displacement is allowed by the elastic deformation of the rubber plate. You may do it.

According to a fourth aspect of the present invention, in the fluid-filled type vibration damping device having a structure according to any one of the first to third aspects, the actuator is adapted to act on the partition member by pneumatic action. It is constituted by a pneumatic actuator having a piston member driven in the approach / separation direction, wherein the flexible member is displaced by the piston member. In such a fluid-filled type vibration damping device having a structure according to this aspect, a simple and lightweight actuator is advantageously realized. In particular, in the case of an automobile vibration isolator, the characteristics of the vibration isolator can be more advantageously switched and controlled by driving the actuator using the negative pressure and the atmosphere generated in the intake system of the internal combustion engine. Become.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, in order to clarify the present invention more specifically, representative embodiments of the present invention will be described.
This will be described in detail with reference to the drawings.

First, FIG. 1 shows an engine mount 10 according to a first embodiment of the present invention. In this engine mount 10, a first mounting member 12 and a second mounting member 14 as a first mounting member and a second mounting member arranged at a predetermined distance from each other are interposed therebetween. The first and second mounting brackets 12 and 14 are attached to one of the vehicle body side and the power unit side, respectively. Is supported on the vehicle body. Further, at the time of mounting on a car, the weight of the power unit is exerted and the main rubber elastic body 16 is elastically deformed.
The first mounting member 12 and the second mounting member 14 are displaced by a predetermined amount in a direction approaching each other, and main vibration for the purpose of damping vibration is input in a substantially vertical direction in the drawing. ing. In the following description, the up-down direction refers to the up-down direction in FIG. 1 in principle.

More specifically, the first mounting member 12 has a substantially disk shape, and a mounting bolt 18 protruding upward in the axial direction is fixed to a central portion. At the center of the lower surface of the first mounting member 12, a support 20 having a hollow substantially inverted truncated cone shape protruding downward is fixedly mounted. An umbrella fitting 21 extending outward in a direction perpendicular to the axis is fixed by caulking. The first mounting bracket 12 is fixedly mounted on a power unit (not shown) by mounting bolts 18.

On the other hand, the second mounting member 14 has a substantially cylindrical shape with a large diameter, and spreads radially outward with a predetermined width at one opening edge (upper in the figure) in the axial direction. The flange portion 22 is formed integrally. Further, an annular locking claw 24 bent radially inward with a small width over the entire circumference in the circumferential direction is formed integrally with the opening peripheral edge at the other side in the axial direction (downward in the figure). The locking claw 24 is formed, for example, by press-forming the second mounting member 14 by deep drawing or the like, and then punching out the center of the bottom wall portion to manufacture the second mounting member 14, thereby providing a special engagement member. It can be advantageously formed by the outer peripheral edge of the bottom wall left by punching, without requiring the step of forming the pawl 24.

The first mounting member 12 is disposed substantially coaxially on one axial side (upper side in the figure) of the second mounting member 14 so as to be spaced apart therefrom. A rubber elastic body 16 is interposed between the second mounting member 14 and the second mounting member 14. The main rubber elastic body 16 has a substantially frusto-conical shape, the lower surface of the first mounting member 12 is vulcanized and bonded to the small-diameter end surface, and the second elastic member 16 is formed with a large-diameter end peripheral surface. Since the upper inner peripheral surface of the second mounting member 14 is vulcanized and bonded, it has a recess 28 that opens downward in the axial direction. That is, the main rubber elastic body 16 is an integrally vulcanized molded product 2 in which the first and second mounting members 12 and 14 are vulcanized and bonded.
The upper opening of the second mounting member 14 is covered with the main rubber elastic body 16 in a fluid-tight manner. The support 20 fixed to the first mounting bracket 12 penetrates the rubber elastic body 16 in the axial direction and protrudes into the recess 28, and the umbrella bracket 21 is positioned in the recess 28. ing.

The main rubber elastic body 16 has a connecting portion between the first mounting member 12 and the second mounting member 14.
One or a plurality of pockets 27 that open toward the inside (downward in the figure) of the second mounting member 14 are formed at predetermined intervals in the circumferential direction.
At the formation site, the main rubber elastic body 16 is thinned to have only the thickness of the bottom wall of the pocket portion 27, so that elastic deformation is relatively easy.

Further, in the second mounting member 14, a partition member 30 and a diaphragm 32 as a flexible film (movable wall member) are accommodated and arranged in an axial central portion and an axial lower opening portion, respectively. ing. The partition member 30 is formed of a hard material such as a synthetic resin or a metal, and has a substantially thick disk shape as a whole. Further, the diaphragm 32 is formed of a thin rubber film which is easily deformed, and a metal ring 34 which is also a support metal is vulcanized and bonded to the outer peripheral surface. Then, the partition member 30 and the diaphragm 32 are sequentially inserted in the axial direction from the lower opening of the second mounting member 14, and then the diameter of the second mounting member 14 is reduced. The member 30 and the metal ring 34 are fitted and fixed to the second fitting 14.

A metal ring 34, which is vulcanized and bonded to the outer peripheral edge of the diaphragm 32, is fitted and fixed to the lower opening of the second mounting bracket 14, thereby lowering the second mounting bracket 14. The opening is closed in a fluid-tight manner by the diaphragm 32, so that inside the second mounting member 14,
A fluid chamber 36 in which an incompressible fluid is sealed is formed. As the sealed fluid, any of water, alkylene glycol, polyalkylene glycol, silicone oil and the like can be adopted. In particular, in the present embodiment, in order to advantageously obtain the fluid resonance effect described below, the viscosity is set to 0. .1Pa.
A low-viscosity fluid of s or less is suitably employed. In the present embodiment, a thin seal rubber layer 38 is formed integrally with the main rubber elastic body 16 over substantially the entire inner peripheral surface of the second mounting member 14, and the partition member 30 and the metal ring 34 are formed. A high degree of fluid tightness is given to a portion where the second fitting 14 is fitted.

The sealing of the incompressible fluid into the fluid chamber 36 is performed, for example, by separating the partition member 30 from the integrally vulcanized molded product 26.
Or by assembling the diaphragm 32 in an incompressible fluid. That is, as shown in FIG. 2, an integrally vulcanized molded product 26, a partition member 30, and a diaphragm 32, which are manufactured separately, are prepared.
They are immersed in an incompressible fluid, and the second fitting 14 of the integrally vulcanized molded product 26 is made in the incompressible fluid.
Then, the partition member 30 and the diaphragm 32 (metal ring 34) are inserted, and then the diameter of the second mounting member 14 is reduced by octagonal drawing or the like, so that the mount body 64 having the fluid chamber 36 is advantageously provided. It can be manufactured. The metal ring 34 is inserted radially inward of the locking claw 24 formed on the peripheral edge of the opening of the second fitting 14, and the diameter of the second fitting 14 is reduced thereafter. The locking claw 24 prevents the metal ring 34 from coming off in the axial direction.

The partition member 30 is connected to the second mounting member 14.
The fluid chamber 36 is divided into upper and lower parts by the partition member 30 by being fitted and fixed to the axial intermediate portion of the fluid chamber 36, so that the wall is located above the partition member 30. A pressure receiving chamber 40 in which a part of the wall is formed of the main rubber elastic body 16 is formed, while an equilibrium chamber 42 in which a part of the wall is formed of the diaphragm 32 is formed below the partition member 30. ing. That is, when vibration is input between the first mounting member 12 and the second mounting member 14, vibration is input to the pressure receiving chamber 40 based on the elastic deformation of the main rubber elastic body 16 and a pressure change occurs. On the other hand, the equilibrium chamber 42 is easily allowed to change in volume based on the deformation of the diaphragm 32 while being tightened. The diaphragm 32 has a slack wavy shape so that its deformation can be easily tolerated.

The pressure receiving chamber 40 is mounted under the mounted state.
At the approximate center of the inside, an annular constriction 43 is formed between the outer peripheral surface of the umbrella bracket 21 and the inner peripheral surface of the pressure receiving chamber 40 by positioning the umbrella bracket 21. When vibration is input between the mounting bracket 12 and the second mounting bracket 14, the umbrella bracket 21 is vibrated in the axial direction within the pressure receiving chamber 40, and the fluid flows through the constricted portion 43 within the pressure receiving chamber 40. Is to be generated.

Further, the partition member 30 has a thick disk shape, is opened on the outer peripheral surface, and extends in the circumferential direction with a length of less than one round (about 3/4 round in the present embodiment). Outer groove 4
4 and an inner circumferential groove 4 which is open on the lower surface in the axial direction and extends for a length of one circumference or less in the circumferential direction (in the present embodiment, about 周 circumference).
6 are formed. Then, the outer peripheral surface of the partition member 30 is brought into close contact with the inner peripheral surface of the second mounting bracket 14 via the seal rubber layer 38, and the outer peripheral side groove 44 is fluid-tightly covered by the second mounting bracket 14. As a result, both ends are connected to the pressure receiving chamber 40 and the equilibrium chamber 42, and the pressure receiving chamber 40 and the
First orifice passage 4 allowing fluid flow between
8 are formed.

The inner peripheral groove 46 is covered by a substantially disk-shaped cover 50 as a cover member superposed on the lower surface. The lid body 50 has a thin plate shape formed of a hard material such as metal or resin, and is formed by, for example, punching a metal plate, and is closely overlapped with the lower surface of the partition member 30. Thereby, the opening of the inner peripheral side groove 46 is covered in a fluid-tight manner. In particular, in the present embodiment, the fitting tube portion 5 extending axially downward from the outer peripheral edge of the partition member 30.
1 is formed integrally, and an annular rib 53 protruding downward in the axial direction is integrally formed on the outer peripheral edge of the lid 50, and the annular rib 53 is press-fitted and fixed to the fitting tubular portion 51. As a result, the partition member 30 and the fitting cylinder 51 are integrally assembled with each other. In addition, after these partition member 30 and the fitting cylinder part 51 are previously assembled outside the fluid,
It is desirable to assemble the main rubber elastic body 16 with the integrally vulcanized molded product 26 in a fluid from the viewpoint of assembling workability and the like.

Further, the inner circumferential groove 46 is formed such that one end in the circumferential direction is bent or curved inward in the radial direction of the partition member 30 and extends radially until reaching the center axis of the partition member 30. Extends to. One end in the circumferential direction of the inner peripheral groove 46 is connected to the pressure receiving chamber 40 through a communication hole 55 formed in the bottom surface of the concave groove 46 of the partition member 30, while the inner peripheral groove is The other end in the circumferential direction of the groove 46 is
Of the equilibrium chamber 4 through the central communication hole 57 drilled in the center of
2 are connected. As a result, a second orifice passage 52 that allows fluid flow between the pressure receiving chamber 40 and the equilibrium chamber 42 is formed. The opening of the second orifice passage 52 on the equilibrium chamber 42 side is formed by the central communication hole 57 of the lid 50, and is located substantially at the center of the partition member 30 and extends downward in the axial direction. In addition, the periphery of the opening is a flat surface formed by the lid 50.

The partition member 30 has an inner peripheral groove 46.
In a portion where is not formed, an accommodating recess 54 that opens to the lower surface in the axial direction is formed. This housing recess 54
Is formed to extend in the circumferential direction with a substantially constant width in the radial direction. In the present embodiment, in particular, it is formed to have a width slightly larger than the inner circumferential groove 46 and less than half the circumferential length.
Further, a rubber elastic plate 56 is housed and arranged in the housing recess 54, and the opening of the housing recess 54 is
Covered with 0. The rubber elastic plate 56 has a flat plate shape thinner than the depth dimension of the accommodation recess 54, and has an outer peripheral edge integrally formed with a protruding edge 58 protruding to both sides. When the protruding edge portion 58 is sandwiched between the bottom surface of the housing recess 54 and the lid 50, the rubber elastic plate 56 is located at an intermediate portion in the depth direction within the housing recess 54 and spreads in an expanded state. , Are arranged so as to partition the inside of the accommodation recess 54. Then, the internal pressure of the pressure receiving chamber 40 and the internal pressure of the equilibrium chamber 42 are applied to the upper and lower surfaces of the rubber elastic plate 56 through the through holes 60 formed in the bottom wall portion of the housing recess 54 and the lid body 50, respectively. When the rubber elastic plate 56 is elastically deformed based on the pressure difference between the two chambers 40 and 42, the rubber elastic plate 56
A substantial fluid flow between the pressure receiving chamber 40 and the equilibrium chamber 42 is generated through the through hole 60 by an amount of fluid corresponding to the amount of elastic deformation of the pressure receiving chamber 40.

Particularly, in the present embodiment, the first orifice passage 48 can exhibit a vibration damping effect (attenuation effect) against low-frequency vibrations such as shakes based on the resonance action of the fluid flowing inside the first orifice passage 48. In addition, the length of the passage, the sectional area, and the like are adjusted. Also, the second orifice passage 52
The ratio of the passage length: L to the cross-sectional area: A: A / L is set to be larger than that of the first orifice passage 48, and when the medium frequency vibration such as idling vibration is input, the first orifice Tuning is performed so that an effective vibration damping effect (vibration insulation effect) can be exhibited in a state where the passage 48 is substantially closed. In the present embodiment, as is apparent from the drawings, the second orifice passage 52 is formed with a larger passage cross-sectional area and a smaller passage length than the first orifice passage 48. Furthermore, when the high frequency vibration such as a muffled sound is input, the housing recess 54 is set in the pressure receiving chamber 40 when both the first and second orifice passages 48 and 52 are substantially closed.
By allowing a substantial fluid flow based on the elastic deformation of the rubber elastic plate 56 between the and the equilibrium chamber 42, the increase in the pressure of the pressure receiving chamber 40 is reduced or eliminated, thereby avoiding a remarkably high dynamic spring. It is tuned so that an excellent vibration isolation effect (vibration insulation effect) can be maintained. In order to stably allow fluid flow through the through hole 60 even at the time of vibration input in a high frequency range, a concave portion 62 is formed in the upper bottom wall portion of the housing concave portion 54 to be thinned. As a result, the flow path formed by the through hole 60 can
It is formed with a sufficiently large cross-sectional area and a small length.

In the present embodiment, in particular, when vibrations in a higher frequency range are input such that the fluid flow resistance through the through-holes 60 is significantly increased, the constriction portion 4 is formed in the pressure receiving chamber 40.
3 so that an effective vibration damping effect (vibration insulation effect) is exhibited based on the resonance action of the fluid flowing through
The channel cross-sectional area, length, and the like of the constricted portion 43 are adjusted. Moreover, in the present embodiment, the elastic deformation of the main rubber elastic body 16 due to the change in the internal pressure of the pressure receiving chamber 40 is caused by the pocket portion 27.
As a result, the flow rate of the fluid in the pressure receiving chamber 40 and, consequently, through the constricted portion 43 is advantageously secured, so that a more excellent vibration damping effect is exhibited.

Further, the mount body 64 structured as described above is located below the second mounting bracket 14,
A negative pressure type actuator 66 as an actuator is provided and assembled. In this negative pressure actuator 66, a substantially disk-shaped rubber elastic wall 70 is axially overlapped with a substantially disk-shaped outer wall member 68 formed of a rigid material such as a synthetic resin or a metal. A working air chamber 72 is formed between the facing surfaces of the outer wall member 68 and the rubber elastic wall 70 so as to be sealed with respect to the outer space. The working air chamber 72 is fixed to the lower end of the case cylinder 74 in the axial direction. It is attached.

The case tube fitting 74 has a thin, large-diameter cylindrical shape. The lower end portion in the axial direction is reduced in diameter to form a fitting portion 76. An annular locking projection 78 protruding inward in the radial direction is integrally formed, and a bracket 80 is attached to the upper opening in the axial direction. This bracket fitting 80
Has a thick large-diameter cylindrical shape, and is integrally formed with a flange-like portion 81 extending outward in the radial direction at one (upper) opening peripheral edge in the axial direction. It is fixed to the upper opening of the metal fitting 74 by press fitting or welding. As shown in FIG. 8, an outer wall member 68 and a rubber elastic wall 70 separately manufactured are sequentially inserted from above the case tube fitting 74, and the outer peripheral edge of the outer wall member 68 is attached to the case tube fitting 74. And a fitting ring 82 as an annular metal fitting that is vulcanized and bonded to the outer peripheral surface of the rubber elastic wall 70 by press-fitting, drawing, or the like. The outer wall member 68 and the outer peripheral edge of the rubber elastic wall 70 are overlapped between the locking projection 78 and the fitting ring 82 and are brought into fluid tight contact with each other. A working air chamber 72 is formed between the walls 70.

A pressing member 8 as a piston member having a substantially inverted cup shape is provided at the center of the rubber elastic wall 70.
4 is vulcanized and bonded in a buried state, and a coil spring 86 as a biasing means is accommodated and disposed in the center of the working air chamber 72 so that the outer wall member 68 and the rubber elastic wall
0 between the opposing surfaces. The urging force of the coil spring 86 constantly urges the pressing member 84 fixed to the rubber elastic wall 70 in a direction away from the outer wall member 68 in the axially upward direction.

Further, at the center of the outer wall member 68,
A circular recess 88 projecting into the working air chamber 72 is formed, and a port 90 is integrally formed projecting into the circular recess 88 from the center of the bottom wall of the circular recess 88. An external pipe (not shown) is connected to the port 90 so that the working air chamber 72 is selectively connected to a negative pressure source (not shown) and the atmosphere through the external pipe. Has become. Thus, under the condition in which the atmospheric pressure is applied to the working air chamber 72, the pressing fitting 84 is positioned to protrude upward by the urging force of the coil spring 86, while the negative pressure is applied to the working air chamber 72. Below, the pressing fitting 84 is pulled down (to the outer wall member 68 side) and held against the urging force of the coil spring 86. Note that a buffer stopper rubber 92 protruding toward the circular recess 88 is formed on the upper bottom of the pressing fitting 84 opposed to the upper bottom of the circular recess 88 in the outer wall member 68. The amount of displacement of the press fitting 84 when the 84 is lowered is buffered.

And, as shown in FIG. 1, the negative pressure type actuator 66 as described above is provided with a case cylinder fitting 74.
The bracket 80 fixed to the mount body 64
Is fixed to the second mounting member 14 by press-fitting from the lower side in the axial direction, so that the second mounting member 14 is disposed in the lower opening. Although not explicitly shown in the drawing, a plurality of bolts or bolt insertion holes are provided in the flange-like portion 81 of the bracket fitting 80, so that the second mounting fitting 14 of the mount body 64 is provided. But,
It is configured to be fixedly mounted on a body side of an automobile (not shown) via a bracket 80. The flange portion 81 of the bracket 80 is superposed on the flange portion 22 of the second mounting member 14, and is firmly positioned and fixed in the axial direction. Note that the assembling work of the negative pressure type actuator 66 and the assembling work of the negative pressure type actuator 66 to the mount main body 64 as described above can be advantageously performed in the atmosphere. Further, as is apparent from the above description, in the present embodiment, the case cylinder 74 and the bracket 80 constitute a mounting cylinder for supporting the negative-pressure actuator 66 on the second mounting 14. .

The negative pressure type actuator 66 assembled to the mount main body 64 in this manner has a second orifice in which the upper bottom of the press fitting 84 is formed at the center of the partition member 30 with the diaphragm 32 interposed therebetween. Passage 52
Are arranged to face the opening on the equilibrium chamber 42 side.
In a state where the atmospheric pressure is applied to the working air chamber 72 of the negative pressure type actuator 66, as shown in FIG. 1, the pressing metal 84 presses the center of the diaphragm 32 based on the urging force of the coil spring 86. The part is the partition member 30
And is brought into close contact with the periphery of the opening (central communication hole 57) of the second orifice passage 52, so that the second orifice passage 52 is maintained in a closed state. On the other hand, when a negative pressure is applied to the working air chamber 72 of the negative pressure type actuator 66, the pressing fitting 84
Is pulled down against the urging force of the coil spring 86, and the pressing fitting 84 and the diaphragm 32 are separated from the partitioning member 30, so that the central communication hole 57
Is opened, the second orifice passage 52 is connected to the equilibrium chamber 42, and the second orifice passage 52 is maintained in a communicating state.

That is, under the condition that atmospheric pressure is applied to the working air chamber 72 of the negative pressure type actuator 66, the pressure receiving chamber 4
Fluid flow through the first orifice passage 48 is effectively generated between the zero and the equilibrium chamber 42, and an effective anti-vibration effect against a low-frequency large-amplitude vibration such as a shake is exhibited based on the resonance action of the fluid. When the high-frequency small-amplitude vibration is input, the pressure receiving chamber 40 is set based on the substantial fluid flow through the through hole 60 between the pressure receiving chamber 40 and the equilibrium chamber 42 due to the elastic deformation of the rubber elastic plate 56. Pressure fluctuations are absorbed and reduced, and the vibration damping effect due to the low dynamic spring is exhibited. In the present embodiment, an effective vibration damping effect can be exhibited even for input vibration in a higher frequency range based on the fluid flow through the constricted portion 43 in the pressure receiving chamber 40.

On the other hand, when a negative pressure is applied to the working air chamber 72 of the negative pressure actuator 66, the pressure receiving chamber 40
And the equilibrium chamber 42, the fluid flow through the second orifice passage 52, whose flow resistance is sufficiently smaller than that of the first orifice passage 48, is effectively generated. An effective anti-vibration effect against medium-frequency and medium-amplitude vibration such as idling vibration is exhibited.

Therefore, by selectively applying the atmospheric pressure and the negative pressure to the working air chamber 72 of the negative pressure type actuator 66 in accordance with the running state of the vehicle or the like, the vibration control characteristics of the engine mount 10 are switched. You can do
Therefore, it is possible to selectively provide the engine mount 10 with the optimum vibration damping characteristics for the input vibration. The case cylinder 74 supporting the negative pressure type actuator 66 is provided with a communication hole 94 penetrating in and out, and through this communication hole 94, a sealed state formed between the diaphragm 32 and the rubber elastic wall 70. The space is communicated with the external space, and the diaphragm 3
2 is easily and stably allowed.

In the engine mount 10 having the above-described structure, the first orifice passage 48 is formed on the outer peripheral edge of the partition member 30, and the second orifice passage 52 and the rubber elastic plate 56 are connected to each other. By forming or disposing the first orifice passage 48 in the radially intermediate portion, the first orifice passage 48 is set in a low frequency range, and the second orifice passage 5
2 can be tuned to the middle frequency range, and the rubber elastic plate 56 can be tuned to the high frequency range, respectively, and the first and second orifice passages 48 and 52 and the rubber elastic plate 56 can be connected to the partition member 30. Therefore, it can be formed with excellent space efficiency.

Therefore, according to this embodiment, over a wide frequency range of the low frequency range, the middle frequency range, and the high frequency range,
Engine mount 10 that can demonstrate excellent vibration isolation effect,
It can be advantageously formed with a simple structure and a compact size.

The embodiment of the present invention has been described in detail above, but this is merely an example.
By the specific description in such an embodiment,
It is not to be construed as limiting.

For example, the outer peripheral groove 44 forming the first orifice passage 48, the inner peripheral groove 46 forming the second orifice passage 52, and the accommodating recess 54 in which the rubber elastic plate 56 is disposed. In any case, the length, width, and the like are appropriately designed according to the required vibration isolation characteristics and the like,
Its shape and structure are by no means limited.

The umbrella fitting 21, the pocket 27, and the like employed in the above embodiment are not essential in the present invention.

Further, the specific structure of the mounting cylinder for supporting the actuator on the second mounting metal, the structure for mounting the actuator to the mounting cylinder, and the like are different from those of the first embodiment. Various structures can be employed. Specifically, for example, the bracket 80 attached to the body is extended downward in the axial direction, and the fitting ring 82 of the negative pressure type actuator 66 is attached to the lower end in the axial direction.
Is fixed, the negative pressure type actuator 66
Can be directly attached to the bracket 80. Alternatively, an annular plate-shaped stepped portion extending radially outward is provided near the lower end portion with respect to the cylindrical wall portion of the case cylindrical member 74, and the stepped portion and the opening peripheral edge portion are directed radially inward. Between the outer wall member 68 of the negative pressure type actuator 66 and the rubber elastic wall 7
The negative pressure actuator 66 can be directly assembled to the bracket 80 by caulking and fixing each outer peripheral edge of the 0 (fitting ring 82).

Further, as a negative pressure type actuator,
It is needless to say that various types of structures can be adopted without being limited to the examples, and that an electromagnetic or electric actuator or the like can also be adopted.

In the above-described embodiment, a specific example in which the present invention is applied to an engine mount for an automobile has been described. However, the present invention is applicable to an anti-vibration device in an automobile body mount or the like or various devices other than an automobile. It is, of course, equally applicable.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, the present invention can be implemented in a form in which various changes, modifications, improvements, and the like are made.
It goes without saying that all such embodiments are included within the scope of the present invention, without departing from the spirit of the present invention.

[0048]

As is apparent from the above description, in the fluid filled type vibration damping device having the structure according to the present invention, the partition member for separating the pressure receiving chamber and the equilibrium chamber has the first orifice passage and the second orifice passage. Both the orifice passage and the hydraulic absorption mechanism using the movable plate can be formed with sufficient tuning freedom and excellent space efficiency. The fluid-filled type vibration damping device that can effectively exhibit the vibration damping effect based on the above can be formed compactly with a simple structure.

[Brief description of the drawings]

FIG. 1 is an explanatory longitudinal sectional view showing an engine mount as a first embodiment of the present invention, which is taken along a line II in FIG. 3;
It is a figure corresponding to a cross section.

FIG. 2 is an explanatory diagram for explaining an assembling process of a mount main body constituting the engine mount shown in FIG. 1;

FIG. 3 is a plan view showing a single partition member constituting the engine mount shown in FIG. 1;

FIG. 4 is a bottom view of the partition member shown in FIG.

FIG. 5 is a view taken in the direction of arrows VV in FIG. 3;

6 is a view taken in the direction of arrows VI-VI in FIG. 3;

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 3;

FIG. 8 is an explanatory diagram for explaining an assembling process of a negative pressure type actuator constituting the engine mount shown in FIG. 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 engine mount 12 first mounting bracket 14 second mounting bracket 16 main rubber elastic body 26 integrally vulcanized molded product 30 partition member 32 diaphragm 36 fluid chamber 40 pressure receiving chamber 42 equilibrium chamber 48 first orifice passage 50 lid 52 Second orifice passage 56 Rubber elastic plate 64 Mount body 66 Negative pressure actuator

Claims (4)

[Claims] A first mounting member is provided at a distance from one axial side of an opening of a second mounting member having a substantially cylindrical shape, and the first mounting member and the second mounting member are arranged. Are connected by a rubber elastic body, and one axial opening of the second mounting member is fluid-tightly covered, and the other axial opening of the second mounting member is covered with a flexible film. By covering the cover in a fluid-tight manner, and further arranging a partition member between the main rubber elastic body and the flexible membrane and fixedly supporting the partition member with the second mounting member, the partition member and the main rubber elastic body are fixed. A pressure receiving chamber to which vibration is input is formed between the opposing surfaces of the body, and a balance chamber having a variable volume is formed between the partition member and the flexible membrane, and the pressure receiving chamber and the balance chamber communicate with each other. And a second orifice tuned to a higher frequency range than the first orifice passage. While forming a orifice passage in the partition member, an actuator is disposed on the opposite side of the equilibrium chamber across the flexible membrane, and the flexible membrane is displaced by the actuator to form the partition. In a fluid-filled type vibration damping device in which the second orifice passage is blocked / communicated by contacting / separating from an opening of the second orifice passage in a member, the first orifice passage is An outer peripheral portion of the partition member is formed so as to extend in a circumferential direction, and the second orifice passage extends in a radial direction at an intermediate portion in a radial direction of the partition member by a length less than one round in a circumferential direction. A side is open to the pressure receiving chamber side, and the other end in the circumferential direction extends radially inward so as to open to the equilibrium chamber side substantially at the center of the partition member, while a radial intermediate portion of the partition member is formed. And a movable plate, to which the internal pressure of the pressure receiving chamber and the equilibrium chamber is applied to each one surface, is disposed so as to be displaceable by a predetermined amount between the circumferential end portions of the second orifice passage. Fluid filled vibration isolator. 2. The fluid according to claim 1, wherein the first orifice passage is formed by covering a circumferential groove that opens in an outer peripheral surface of the partition member and extends in a circumferential direction with the second mounting member. Enclosed vibration damping device. 3. The second orifice passage is opened on one side in the axial direction of the partition member, and extends radially in a radially intermediate portion, and one end in the circumferential direction faces radially inward. The groove formed so as to extend is formed by covering with a lid member superimposed on the partition member, and between the circumferential ends of the groove, extends in the circumferential direction and is the same as the groove. A storage recess that opens to the side is formed, the movable plate is received and arranged in the storage recess, and the storage recess is covered with the lid member, and a bottom wall portion and a lid member of the storage recess are provided. To
3. A communication hole according to claim 2, wherein said housing recess is formed with a communication hole communicating with said pressure receiving chamber or said equilibrium chamber, and the internal pressure of said pressure receiving chamber and said equilibrium chamber is applied to each one surface of said movable plate. Fluid filled type vibration damping device. 4. The actuator according to claim 1, wherein the actuator comprises a pneumatic actuator having a piston member driven in a direction of approaching / separating from the partition member by the action of air pressure, and the piston member displaces the flexible membrane. The fluid filled type vibration damping device according to any one of claims 1 to 3, wherein the vibration damping device is used.