JP2001227581A - Vibration control device, and actuator therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration control device with novel structure having an air chamber formed in a sealed condition from an external space which can reduce or prevent the pressure fluctuation in the air chamber while completely preventing invasion of water and dust in the air chamber. SOLUTION: A permeable waterproof membrane 94 is disposed on a wall to demarcate the air chamber 62 from the external space to allow the air to pass between the air chamber 62 and the external space via the permeable waterproof membrane 94.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device having an air chamber formed in a sealed state with respect to an external space, and an actuator suitably used in such a vibration damping device. The present invention relates to a vibration isolator used as various vibration isolating connectors or vibration isolating supports such as body mounts, vibration isolating supports, and vibration dampers, and an actuator that can be used in such a vibration isolating device.

[0002]

2. Description of the Related Art In a member such as an automobile body where vibration (including noise caused by vibration) is a problem, the member is interposed between two members to reduce the vibration and is controlled by a vibration source. Vibration damping couplings such as engine mounts or vibration damping supports that reduce the transmission of vibration to the vibration damping object, and dynamic dampers that are directly attached to the vibration damping object and directly reduce vibration of the vibration damping object itself An anti-vibration device such as a vibration isolator is preferably employed. As one type of such an anti-vibration device, one side of a displacement member that is deformed or displaced at the time of vibration input is sealed against an external space. One with an air chamber is known.

For example, Japanese Patent Publication No. 7-54131 discloses that a first mounting member and a second mounting member are connected by a main rubber elastic body while a part of a wall is formed by the main rubber elastic body. The pressure receiving chamber and the equilibrium chamber whose wall part is composed of a flexible membrane are formed, an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber are connected to each other. In a fluid filled type vibration damping device having an orifice passage communicating with a flexible membrane, a cover member is provided behind the flexible membrane, and an air chamber is formed between the flexible membrane and the cover member.
There is disclosed a fluid-filled type vibration damping device that protects the flexible film from the outside while permitting deformation of the flexible film.

In Japanese Patent Application Laid-Open No. Hei 10-227329, a first mounting member and a second mounting member are connected by a main rubber elastic body, and a part of a wall portion is constituted by the main rubber elastic body. To form a fluid chamber in which the incompressible fluid is sealed, and another part of the wall of the fluid chamber is constituted by a movable member displaceably supported with respect to the second mounting member. A closed air chamber is formed behind the movable member, and a vibrating means for applying a vibrating force to the movable member to actively vibrate is accommodated in the air chamber so that the vibrating means is externally provided. There is disclosed an active vibration isolator designed to protect against vibration.

Further, Japanese Patent Application Laid-Open Nos. Hei 4-95633 and Hei 8-313718 disclose that a mass member having a predetermined mass is elastically connected to a supporting member via a rubber elastic body so as to be relatively displaceable. A vibrating means for forming a sub-vibration system and forming a closed air chamber between the support member and the mass member to apply a vibrating force to the mass member to actively vibrate the mass member, An active vibration damper that accommodates and arranges in a room to protect the vibration means from the outside is disclosed.

Further, Japanese Patent Application Laid-Open No. 6-505676 and the like include a permanent magnet and a coil member which are disposed so as to be relatively displaceable, and reduce a magnetic force or an electromagnetic force generated by energizing the coil member. By applying a vibration force based on the vibration isolator to generate an active vibration isolating effect, and by setting the working space including the relative displacement area between the permanent magnet and the coil member as a closed air chamber. Also, there is disclosed an actuator for a vibration isolator in which a mechanism for generating a vibration force is protected from the outside.

By the way, such a vibration isolator, a vibration damper,
In the actuator, it is important to prevent water or foreign matter from entering the air chamber in order to secure a stable operation and obtain a desired vibration damping effect.

[0008] However, if the air chamber is completely sealed, a change in pressure in the air chamber due to a temperature change or irreversible air permeation through a rubber film or the like adversely affects the vibration damping performance or causes the occurrence. Due to the negative pressure, water or the like is sucked into the air chamber from a slight gap, and there is a possibility that durability or the like may be reduced.

[0009] In order to deal with such a problem,
For example, in an anti-vibration device or an actuator for an automobile, it is conceivable to provide an air passage that communicates an air chamber in the anti-vibration device or the actuator with a space where water does not enter, such as a vehicle room, using an air hose or the like. When the air passage is formed, there is a problem that the assembling is troublesome and a significant increase in cost cannot be avoided.

[0010]

Here, the present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to completely prevent intrusion of water, dust, and the like into an air chamber. Another object of the present invention is to provide a vibration damping device having a novel structure and an actuator for the vibration damping device, which can reduce or prevent the pressure fluctuation of the air chamber.

[0011]

An embodiment of the present invention which has been made to solve such a problem will be described below. In addition, each of the components employed in each of the embodiments described below can be employed in any combination as much as possible. In addition, aspects and technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or based on an inventive idea that can be understood by those skilled in the art from the descriptions. It should be understood that the

That is, the first aspect of the present invention is that a displacement member which is deformed or displaced by an exciting force passively or actively applied at the time of vibration input has one side closed to an external space. In the vibration isolator provided with the provided air chamber, the air chamber is connected to an external space through a breathable waterproof film.

[0013] In the vibration isolator having the structure according to this aspect, the air-permeable waterproof film is provided between the air chamber and the external space, so that the air-permeable waterproof film is formed based on the pressure difference between the air chamber and the external space. While the flow of air between the air chamber and the external space is allowed based on the permeability of the breathable waterproof membrane,
The entry of water and dust from the external space into the air chamber can be almost completely prevented based on the waterproof property of the breathable waterproof film.
Therefore, in such a vibration damping device, a reduction in vibration damping performance and durability due to pressure fluctuations in the air chamber and intrusion of foreign matter into the air chamber is avoided as much as possible, and the intended vibration damping effect is achieved. It can be obtained effectively and stably.

In this embodiment, the air-permeable waterproof membrane may be a porous membrane made of a hydrophobic resin such as polytetrafluoroethylene (PTFE) or polyolefin, a mesh, a woven or nonwoven fabric, or an ordinary resin. A porous membrane or the like coated with a waterproof resin can be advantageously used. Among them, in particular, a PTFE membrane that has been made porous by stretching can be suitably employed because it has both excellent waterproofing performance and ventilation performance. Specifically, for example, Japan Gore-Tex product “Gore-Tex” (Registered trademark) or the like is advantageously employed.

According to a second aspect of the present invention, there is provided a vibration isolator having a structure according to the first aspect, wherein a first mounting member attached to one member to be vibration-isolated and connected, The second mounting member to be attached to the other member is elastically connected to each other by a main rubber elastic body, and a part of a wall portion is formed by the main rubber elastic body, and an incompressible fluid is sealed therein. While forming the pressure receiving chamber, a part of the wall portion is formed of a flexible film which is easily deformed to form an equilibrium chamber filled with an incompressible fluid, and the pressure receiving chamber and the equilibrium chamber are communicated with each other. By providing an orifice passage, the displacement member is constituted by such a flexible film, and the air chamber is formed on the opposite side of the displacement member from the equilibrium chamber.
In such a vibration isolator having a structure according to this aspect, a passive fluid-filled type vibration isolator can be advantageously realized, and is suitably employed as, for example, an engine mount or a body mount for an automobile. obtain. In this case, the pressure change of the air chamber formed behind the equilibrium chamber is reduced or prevented, and water and foreign substances are prevented from entering the air chamber. Performance can be achieved.

According to a third aspect of the present invention, there is provided an anti-vibration device having a structure according to the first or second aspect, wherein the first mounting member is mounted on one member to be vibration-isolated and connected, A second mounting member attached to the other member to be vibration-isolated is elastically connected to each other by a main rubber elastic body, and a part of a wall portion is formed by the main rubber elastic body so that an incompressible fluid is formed. While forming the sealed fluid chamber, another part of the wall of the fluid chamber is constituted by a movable member displaceably supported with respect to the second mounting member, so that the movable member has A displacement member is formed, the air chamber is formed on a side of the movable member opposite to the fluid chamber, and a vibration means for applying a vibration force to the movable member to actively vibrate is provided. , Features. In the vibration damping device having the structure according to this aspect, an active fluid-filled vibration damping device can be advantageously realized, and is suitably used in, for example, an engine mount or a body mount for an automobile. obtain. In this case, the change in pressure of the air chamber formed on the opposite side of the fluid chamber of the movable member is reduced or prevented, and the invasion of water and foreign matter into the air chamber is prevented, so that excellent durability and excellent durability are achieved. Stable vibration isolation performance can be realized.

According to a fourth aspect of the present invention, in the third aspect, the vibrating means is housed and arranged in the air chamber. In the vibration isolator having the structure according to the present aspect, the vibration means can be advantageously protected by housing and disposing the vibration means in an air chamber sealed with respect to the external space. Stabilization can be achieved, and further improvement in the stability of the vibration isolation performance can be achieved.

According to a fifth aspect of the present invention, there is provided a vibration isolator having a structure according to the first aspect, wherein a mass member having a predetermined mass is provided with respect to a support member attached to a vibration member to be subjected to vibration isolation. Are elastically connected to each other via an elastic support so as to be relatively displaceable to form a sub-vibration system, the air chamber is formed between the support member and the mass member, and the displacement member is formed by the elastic support. On the other hand, a vibrating means for applying a vibrating force to the mass member to actively vibrate is accommodated and arranged in the air chamber. In such a vibration isolator having a structure according to this aspect,
An active type vibration damper can be advantageously realized, and can be suitably adopted, for example, in a vehicle body vibration damper or the like. In this case, a change in pressure of the air chamber formed between the support member and the mass member is reduced or prevented, and water and foreign matter are prevented from entering the air chamber, so that excellent durability and stability are achieved. Thus, the anti-vibration performance can be realized.

In a sixth aspect of the present invention, there is provided a fluid filled type vibration damping device having a structure according to any one of the third to fifth aspects, wherein a partition wall for dividing the air chamber into two is provided. On both sides of the partition wall, a first divided air chamber in which a part of a wall portion is constituted by the displacement member, and a second divided air chamber communicated with the external space via the breathable waterproof membrane. And that a ventilation orifice communicating the first divided air chamber and the second divided air chamber with each other is provided.
Features. In the fluid-filled type vibration damping device having the structure according to the present aspect, the air pressure applied to the first divided air chamber passes through the ventilation orifice, and the second divided air provided with the permeable waterproof membrane is provided. Room. Therefore, even when a periodic or sudden pressure change occurs in the air chamber due to the displacement member constituting the wall of the first divided air chamber, the ventilation orifice is tuned to an appropriate cross-sectional area or length. By doing so, it is possible to reduce or avoid the transmission of significant pressure fluctuations to the second divided air chamber, and as a result, it is possible to suppress the pressure exerted on the gas permeable waterproof membrane, and thus to improve the gas permeability. The durability of the waterproof film can be improved.

Further, a seventh aspect of the present invention includes a permanent magnet and a coil member which are disposed so as to be relatively displaceable, and which is based on a magnetic force or an electromagnetic force generated by energizing the coil member. An actuator for an anti-vibration device that exerts a vibration force on an anti-vibration device to generate an active anti-vibration effect, wherein a cover member that partitions an operation space including a relative displacement region between the permanent magnet and the coil member from an external space. And that the working space is an air chamber in a sealed state, and that the air chamber is communicated with an external space via a breathable waterproof membrane.
Features. In such an actuator having a structure according to this aspect, an actuator for a vibration isolator can be advantageously realized, and for example, is preferably employed as a separate actuator that is advantageously employed in an active vibration isolator. Can be done. In this case, the pressure change of the air chamber, which is separated from the external space by the cover member and is sealed, is reduced or prevented, and the entry of water and foreign matter into the air chamber is prevented. That is, it is possible to realize the performance and stable vibration isolation performance.

In the second to seventh aspects of the present invention as described above, the same breathable waterproof membrane as that of the first aspect can be suitably adopted, and particularly, the stretchable waterproof membrane can be stretched. The PTFE membrane made porous is more preferably adopted because it has both excellent waterproofing performance and ventilation performance.

[0022]

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

FIG. 1 shows an automotive engine mount 10 according to a first embodiment of the present invention. In this figure, reference numeral 12 denotes a first support member as a first attachment member, and reference numeral 14 denotes a second support member as a second attachment member. Rubber elastic body 16 interposed between
Are elastically connected to each other. In the engine mount 10, the first support 12
By attaching one of the first and second support members 14 to the power unit side or the body side, the power unit can be supported on the body with vibration isolation.

More specifically, the first support fitting 12 is
An upper metal fitting 20 and a lower metal fitting 22 each having a substantially cylindrical shape with a bottom and provided with outer flange portions 16 and 18 at the periphery of the opening are overlapped with each other on their opening sides. It is configured by bolt connection. At the center of the bottom wall of the upper bracket 20, a mounting bolt 24 is provided so as to protrude outward, and the first supporting bracket 12 is attached to the power unit side or the body by the mounting bolt 24. It can be attached to the side.

A space 30 having a predetermined size is formed inside the first support fitting 12 between the upper fitting 20 and the lower fitting 22 by the concave portions 26 and 28 of the upper and lower fittings 20 and 22. Have been. In this space 30, a diaphragm 32 as a flexible film having a substantially thin disk shape and partitioning the space into two is accommodated and arranged, and its outer peripheral edge is formed by the upper fitting 20 and the lower fitting. The diaphragm 32 is attached by being sandwiched between the outer flange portions 16 and 28 of the 22. That is, the diaphragm 32 allows the space 30 to be formed in the recess 2 of the upper fitting 16.
That is, it is fluid-tightly partitioned between the side 6 and the side of the recess 28 of the lower bracket 18.

On the other hand, the second support member 14 has a substantially large-diameter annular block shape, and is opposed to the lower metal member 22 of the first support member 12 at a predetermined distance in the axial direction. It has been impatient. And these first support fittings 12
A rubber elastic body 34 as a main body rubber elastic body is interposed between the second support fitting 14 and the second support fitting 14, and the two support fittings 12 and 14 are elastically connected by the rubber elastic body 34. It has been impatient. The rubber elastic body 34 has a tapered cylindrical shape or a truncated cone shape, and has a bottom wall portion of the lower bracket 22 of the first support bracket 12 with respect to an opening end face on the small diameter side. The outer peripheral surface is fixed, while the axial end surface of the second support member 14 is fixed to the large-diameter opening end surface. That is, the rubber elastic body 34 is formed as an integrally vulcanized molded product having the lower fitting 22 and the second support fitting 14.

Further, the first support fitting 12 and the second support fitting 14 are connected by the rubber elastic body 34, so that an inner hole of the second support fitting 14 is provided therebetween. A recess 36 that opens to the outside is formed.

That is, as is clear from FIG. 1, the opening on the small diameter side of the tapered cylindrical rubber elastic body 34 is closed by the first support fitting 12, so that the recess 36 is formed. Formed in the rubber elastic body 34,
The annular second support fitting 14 is attached to the large diameter opening of the rubber elastic body 34,
The recess 36 is connected to the inner hole of the second support fitting 14.

Further, inside the second support fitting 14,
A diaphragm 38 having a substantially thin disk shape is disposed at the opening of the recess 36. An annular ring-like mounting ring 42 is integrally attached to an outer peripheral edge of the diaphragm 38 via an annular-plate-like support rubber elastic body 40 that extends radially outward. The diaphragm 38 is attached to the second support fitting 14 by bolting the mounting ring 42 to the second support fitting 14. Thereby, the diaphragm 38
Is supported rubber elastic body 40 with respect to second support fitting 14.
It is displaceably mounted based on the elastic deformation of. As is clear from this, in the present embodiment, a displacement member is constituted by the diaphragm 38 and the supporting rubber elastic body 40.

Further, by mounting the vibration plate 38 to the second support fitting 14, the opening of the recess 36 is covered in a fluid-tight manner. A main liquid chamber 44 in which a predetermined incompressible fluid is sealed is formed therein. In addition, as the sealing fluid, for example, water, alkylene glycol, polyalkylene glycol, silicone oil, or the like is preferably used.

That is, in the main liquid chamber 44, a part of the wall is formed of the rubber elastic body 34, and the vibration between the first support fitting 12 and the second support fitting 14 is caused. At the time of input, the internal pressure fluctuation is caused based on the elastic deformation of the rubber elastic body 34, and the other part of the wall formed by the rubber elastic body 34 is displaced. It is constituted by a possible diaphragm 38. As is apparent from this, in the present embodiment, the main liquid chamber 44 constitutes a pressure receiving chamber.

On the other hand, the same incompressible fluid as that of the main liquid chamber 44 is sealed in the recess 28 of the lower fitting 22 in the space 30 formed inside the first support fitting 12. I have. Thereby, the equilibrium chamber 46 whose volume change is easily allowed based on the deformation of the diaphragm 32 is formed by the concave portion 28 of the lower metal fitting 22. A space on the side of the concave portion 26 of the upper fitting 20 which is located on the opposite side of the equilibrium chamber 46 with the diaphragm 32 interposed therebetween is a working air chamber 48 which allows the deformation of the diaphragm 32.

Furthermore, the main liquid chamber 44 and the equilibrium chamber 46
A disc metal fitting 50 is superimposed on the bottom wall of the lower metal fitting 22 that constitutes a partition wall for partitioning and is fixed by bolts.
The disk metal fitting 50 is provided with a circumferential groove 52 extending in the circumferential direction on a surface on which the lower metal fitting 22 is overlapped. Thereby, when the disc metal fitting 50 is superimposed on the lower metal fitting 22, a predetermined length extends in the circumferential direction between the overlapping surfaces of the disk metal fitting 50 and the lower metal fitting 22, and both ends in the circumferential direction are An orifice passage 54 communicated with the main liquid chamber 44 and the equilibrium chamber 46 is formed through a communication hole provided in the lower metal fitting 22 and the disk 50.

When an internal pressure fluctuation is caused in the main liquid chamber 44 at the time of vibration input, the main liquid chamber 44 and the equilibrium chamber 46
When the fluid flows through the orifice passage 54, a predetermined vibration-proof effect is exerted based on the fluid action or resonance action of the fluid. In the present embodiment, the length of the orifice passage 54 and the length of the orifice passage 54 are determined so that a high damping effect can be exerted when a low-frequency large-amplitude vibration such as a shake is input based on the resonance action of the fluid caused to flow through the orifice passage 54. The area is tuned.

On the other hand, on the opposite side (lower side in the figure) of the second support fitting 14 from the side where the rubber elastic body 34 is fixed,
A bottom fitting 56 is provided. And this bottom fitting 56
Is a bottomed cylindrical shape provided with an outer flange portion 58 extending radially outward and a projecting portion 60 projecting radially inward at a predetermined height at an opening peripheral portion. The outer flange portion 58 is integrally fixed to the second support fitting 14 by being bolted to the axial end face of the second support fitting 14. That is, as is apparent from FIG. 1, in this embodiment, behind the diaphragm 38, the back surface of the diaphragm 38, the inner peripheral surface of the second support 14, and the bottom A closed chamber 62 is formed as an air chamber surrounded by the inner peripheral surface.

An electromagnetic drive means 64 is accommodated in the closed chamber 62. This electromagnetic driving means 64
The two magnetic pole portions have a circular block-shaped permanent magnet 66 positioned in the direction of displacement of the diaphragm 38 (vertical direction in the figure). The end face on the magnetic pole side on the opposite side to the diaphragm 38 side is arranged in contact.

Further, the diaphragm 38 of the permanent magnet 66
A substantially thick disk-shaped end fitting 68 is disposed in contact with the end face on the magnetic pole side. Here, the outer diameter of the end fitting 68 is larger than that of the permanent magnet 66 and smaller than the inner diameter of the protrusion 60 formed on the periphery of the opening of the bottom fitting 56. It is projected radially outward from 66 with a predetermined dimension, and its outer peripheral surface is
The inner peripheral surface of the protruding portion 60 of the bottom fitting 56 is opposed to the inner peripheral surface at a predetermined distance in the radial direction. The end fitting 68 and the bottom fitting 56 are connected and fixed to a plurality of fixing bolts 70, so that the permanent magnet 66 is sandwiched and fixed between the two fittings 68, 56. .

The bottom fitting 56 and the end fitting 68
Are formed of a ferromagnetic material such as iron, thereby forming a substantially closed magnetic path around the permanent magnet 66, and a bottom fitting located on the magnetic path. An annular or cylindrical gap 72 continuous in the circumferential direction is formed between the radially opposed surfaces of the 56 projections 60 and the end fittings 68. The fixing bolt 70 connecting the bottom fitting 56 and the end fitting 68 is made of a non-magnetic material such as an aluminum alloy, so that a short circuit of the magnetic path is prevented.

Further, a cylindrical bobbin 74 having a substantially inverted bottom and made of a non-magnetic material such as synthetic resin or aluminum is provided above the end fitting 68 forming the magnetic path at a predetermined distance. It is arranged. And this bobbin 7
The bottom wall portion 4 is fixed to the back surface of the diaphragm 38 with bolts and nuts, while the cylindrical wall portion 76 is formed on the inner peripheral surface of the protruding portion 60 of the bottom fitting 56. And the outer peripheral surface of the end fitting 68 is inserted and disposed movably in the axial direction in a gap portion 72 formed between the outer peripheral surface of the end fitting 68 and the outer peripheral surface of the cylindrical wall portion 76. Has a cylindrical coil 78 fixed thereto.
That is, this allows the coil 78 and the bobbin 74 to be integrally displaceable in the gap portion 72, and the coil 78 is held by the diaphragm 38 via the bobbin 74. -ing A predetermined current is supplied to the coil 78 attached to the bobbin 74 from the outside through the lead 80.

The bottom fitting 56 which defines the sealed chamber 62 in cooperation with the vibration plate 38 and the second support fitting 14 has at least one circumferential position near the outer peripheral edge of the bottom surface. A through-hole 82 communicating the chamber 64 with the external space is formed. Then, a vent filter 84 as shown in FIG.
By closing 2, the sealed chamber 64 is kept in a sealed state.

The vent filter 84 has a housing body 86 and a cap 88 formed of a synthetic resin material. The housing main body 86 has a substantially cylindrical shape as a whole, and is formed with an air passage 89 extending through the central axis in the axial direction. Further, a tapered locking portion 90 having a substantially inverted truncated cone shape is integrally formed at one axial end (lower portion in FIG. 2) of the housing body 86. The side end portion is projected in a hook shape from the cylindrical outer peripheral surface of the housing body 86 to form a step-shaped diameter stop surface 91. On the other hand, a flange 92 extending radially outward is integrally formed near the other end in the axial direction of the housing main body 86, and an outer portion in the axial direction from the flange 92 has a larger diameter and is thicker. It is a meat tube wall portion 95. And this thick wall 9
5, a filter 94 as a waterproof gas permeable membrane is disposed in the air hole 89, and the outer peripheral edge portion is a thick cylindrical wall portion 95.
By being buried in the space, it is assembled so as to spread in the direction perpendicular to the axis and block the ventilation hole 89.

On the other hand, the cap portion 88 has a shallow inverted cup shape, and is externally fitted to the thick cylindrical wall portion 95 of the housing body 86, and may be bonded or locked as necessary. Be attached by being. The bottom surface and the inner peripheral surface of the cap portion 88 are closely overlapped with the axial end surface and the outer peripheral surface of the thick cylindrical wall portion 95 of the housing body 86, and the open end surface of the cap portion 88 is The axially upper opening of the ventilation hole 89 of the housing main body 86 is covered by the cap 88 in a closed state by being closely overlapped with the flange 92.

The overlapping surface of the cap portion 88 of the housing body 86 extends radially inward from the outer peripheral edge of the flange portion 92 and extends axially upward on the outer peripheral surface of the thick-walled cylindrical wall portion 95. Further, a suitable number of continuous grooves 100 radially inwardly extending in the axial direction end surface of the housing body 86 are formed radially in the circumferential direction. Then, the housing body 86 and the cap portion 8 are formed by the concave groove 100.
8 is a gap-shaped communication hole 9 extending in the radial direction between the superposed surfaces 8.
7 is formed, and the axially upper opening of the housing body 86 is opened on the outer peripheral surface through the communication hole 97 to communicate with the external space.

In the present embodiment, the filter 94 in the vent filter 84 is made of polytetrafluoroethylene (hereinafter, ePTFE) made porous by stretching.
It is described. ) Has been adopted. This ePTFE is
Since the filter 94 has excellent waterproofness and air permeability, and the filter 94 made of ePTFE is disposed on the ventilation path 89, the vent filter 84 allows water, dust, etc. Is effectively prevented, and a change in air pressure in the closed chamber 62 can be applied to the external space through the filter 94.

Such ePTFE is disclosed in, for example, Japanese Patent Publication Nos. 43-13560, 51-18991, 51-30277, 56-17216, and the like. It can be manufactured by various known manufacturing methods. For example, a basic eP
As a method for producing TFE, first, a liquid lubricant such as naphtha is mixed with PTFE fine powder to form a paste, and the paste is extruded by a so-called paste extrusion method through preliminary molding. Further, after the lubricant is removed by evaporation from the extruded product, the extruded product is monoaxially or biaxially stretched at a temperature equal to or lower than the melting point of PTFE to make it porous. Usually, after these steps, the product is completed through a firing step in which the expanded porous material is heated to a temperature equal to or higher than the melting point of PTFE and then cooled. Also,
In some cases, the product is fired (heat-treated) without firing or slightly fired.

After the vent filter 84 having such a structure is used, the ring-shaped packing 85 is externally inserted from the locking portion 90 side of the housing body 86, and then the locking portion 9 is inserted.
0 is fitted into the through-hole 82 of the bottom fitting 86 and inserted therethrough, and the locking surface 91 of the locking portion 90 is locked to the inner surface of the bottom fitting 56 so that it is not slid out. Also,
In such a mounted state, the packing 85 is narrowed between the opposing surfaces of the locking portion 90 and the bottom fitting 86, thereby causing the bottom fitting 5.
Six through holes 82 are sealed in a fluid-tight manner.

Accordingly, in the engine mount 10 having the above-described structure, by applying an alternating current to the coil 78, an electromagnetic force (Lorentz force) according to Fleming's left-hand rule is generated on the coil 78. As a result, a driving force proportional to the current is exerted on the diaphragm 38 via the bobbin 74 on which the coil 78 is mounted. Then, the power supply to the coil 78 is controlled, and the main liquid chamber 4 generated by the input vibration is controlled.
By vibrating the diaphragm 38 in accordance with the internal pressure fluctuation of 4, the internal pressure of the main liquid chamber 44 can be controlled, whereby the active or active vibration isolation against the input vibration can be achieved. The effect can be obtained, and the anti-vibration characteristics of the mount can be appropriately changed.

In the engine mount 10, a sealed chamber 62 provided behind the diaphragm 38 is provided.
Since the electromagnetic driving means 64 including the permanent magnet 66 and the coil 78 are arranged, the electromagnetic driving means 64
Is completely prevented from invading water or the like from the external space into the closed chamber 62 provided, and the exciting force by the electromagnetic driving means 64 can be obtained stably, so that the exciting performance is more stable. In addition, the durability of the electromagnetic driving means 64 can be improved.

That is, in the engine mount 10, since the sealed chamber 62 is communicated with the external space through the vent filter 84 including the filter 94 as a gas permeable waterproof film, the filter 94 is waterproof. The intrusion of water, dust, etc. from the external space into the closed chamber 62 can be effectively avoided based on the property, whereby the adverse effect on the vibration isolation performance due to the entry of moisture and foreign matter into the closed chamber 62 is advantageous. Can be prevented. Further, when a static pressure change occurs in the closed chamber 62 due to a temperature change or the like, the static pressure is quickly eliminated and maintained at substantially the atmospheric pressure based on the permeability of the filter 94. Therefore, it is possible to stably obtain the desired anti-vibration performance.

Therefore, such an engine mount 10
In this case, the service life of the electromagnetic drive means, and consequently the service life of the engine mount 10 itself, can be effectively extended, and the main liquid chamber adapted to the large electromagnetic force generated by the electromagnetic drive means 64. Thus, the internal pressure control capability of 44 can be advantageously obtained, so that the intended anti-vibration characteristics can be exhibited with extremely high accuracy and stability over a long period of time.

Next, FIG. 3 shows a vibration damper 102 according to a second embodiment of the present invention. In the following embodiments, the same reference numerals are given to members and parts having the same structure as in the first embodiment, and a detailed description thereof will be omitted.

That is, in the vibration damper 102, a mass metal fitting 106 serving as a mass member is attached to a vibrating body (not shown) to be damped by a mass metal fitting 106 serving as a mass member. It is elastically connected via a body 108, thereby forming one vibration system using the mass metal fitting 106 as a mass system and the support rubber elastic body 108 as a spring system. Also, the mounting bracket 104 and the mass bracket 1
Between 06, an electromagnetic drive mechanism including a coil 110 and a permanent magnet 112 is incorporated, and an exciting force is exerted on the vibration system by this electromagnetic drive mechanism. By applying a vibration force in this vibration system to the vibrating body via the mounting bracket 104, vibration in the vibrating body can be actively suppressed. In addition, in the vibration damper 102 of the present embodiment, an effective vibration damping effect can be exhibited with respect to the vertical vibration in FIG. In the following description, the vertical direction in FIG. 3 is simply referred to as the vertical direction.

More specifically, the mounting bracket 104 has a substantially truncated conical shape, and a bracket 114 is superimposed on the lower end surface in the axial direction and fixed by bolts. The bracket 114 has a circular flat plate shape, and has a fixing portion 116 protruding downward and extending radially outward at a plurality of locations on the periphery, and a diagonally upward projecting radially extending portion. The stopper portion 118 is integrally provided, and the fixing portion 116 is fixed to a vibrator (not shown) by a bolt or the like.

On the upper side of the mounting bracket 104 in the axial direction,
A bobbin 120 having a substantially inverted cup shape is provided so as to open upward on the same central axis, and a bolt is provided in a state where the bobbin 120 is superimposed on the upper surface of the mounting bracket 104 at a central portion of the bottom wall portion 122. 124 fixed. The coil 110 is wound around the outer peripheral surface of the cylindrical portion 126 of the bobbin 120 and is fixedly mounted.
In short, the coil 110 is fixedly mounted on the mounting bracket 104 via the bobbin 120.

Further, a mass metal fitting 106 having a large diameter circular block shape is provided on the upper side in the axial direction of the mounting metal fitting 104.
Are spaced apart on the same central axis. And
The outer peripheral surface of the mounting bracket 104 and the opposing surface of the outer peripheral edge of the mass bracket 106 are elastically connected by a substantially thick disk-shaped support rubber elastic body 108, whereby the support rubber elasticity is increased. The body 108 and the mass metal fitting 106 constitute one auxiliary vibration system.

The mass metal fitting 106 is formed of a ferromagnetic material, and has a central hole 128 formed in the center axis thereof, which penetrates in the axial direction. A peripheral groove 130 is formed which extends to open on the lower surface in the axial direction. A cylindrical permanent magnet 112 having both magnetic poles set on both sides in the radial direction is fixedly disposed on the inner wall surface 132 on the outer peripheral side of the peripheral groove 130. The inner diameter of the permanent magnet 112 is set to be larger than the diameter of the inner wall surface 134 on the inner peripheral side of the peripheral groove 130, whereby the inner diameter of the inner wall 134 on the inner peripheral side of the peripheral groove 130 becomes permanent. The inner peripheral surfaces of the magnets 112 are arranged to face each other in the radial direction at a predetermined distance from each other. Also,
The inner surface 134 of the inner peripheral side wall of the peripheral groove 130 and the permanent magnet 1
A cylindrical gap 136 extending continuously in the circumferential direction is formed between the opposing surfaces of the inner peripheral surface of the cylinder 12. In short, a closed magnetic path is formed between the mass metal fitting 106 and the permanent magnet 112, and an air gap 136 is set on the magnetic path. Thereby, the inner surface 13 of the inner peripheral side wall portion of the peripheral groove 130 facing the permanent magnet 112 with the air gap 136 interposed therebetween.
4, a magnetic pole different from the magnetic pole on the inner peripheral surface of the permanent magnet 112 is generated, so that the air gap 13 sandwiched between the magnetic poles is generated.
6, a magnetic field is effectively formed. The coil 110 supported by the bobbin 120 with respect to the gap 136 is inserted and arranged so as to be relatively displaceable in the axial direction with a predetermined gap therebetween.

Further, a solid connecting rod 138 protruding axially upward from the central axis is fixed to the axially upper surface of the mounting bracket 104 by a bolt 124, and a central hole 128 of the mass metal fitting 106. Is arranged to pass through. The protruding tip of the connecting rod 138 is fixed to the leaf spring 140 by a bolt 142. The leaf spring 140 has a thin disk shape, and a slit or the like extending spirally in the circumferential direction is formed, so that elastic characteristics in the axial direction are adjusted. The annular shape is arranged above the mass metal fitting 106 in the axial direction and in the direction perpendicular to the axis. The outer peripheral edge portion is overlapped with the upper end surface of the mass metal fitting 106 and is press-fitted and fixed to the mass metal fitting 106. The ring metal 143 is attached by being clamped and fixed between the mass metal fitting 106 and the upper end surface thereof. That is, the leaf spring 140 is connected to the mounting fitting 104 via the connecting rod 138, whereby the leaf spring 140 cooperates with the supporting rubber elastic body 108 to form the mass fitting 106.
Are elastically supported with respect to the mounting bracket 104. As is apparent from this, in the present embodiment, an elastic support is constituted by the support rubber elastic body 108 and the plate spring 140.

Further, on the upper side of the leaf spring 140, a partition plate 146 having an inverted dish shape whose bottom portion protrudes upward is disposed, and the central portion having the thin disk shape is provided with the leaf spring 140. Are arranged at a predetermined distance axially upward from, and the outer peripheral edge is superimposed on the leaf spring 140, and is fixed together with the leaf spring 140 by the ring metal 143 between the mass metal fitting 106. Have been. The partition plate 146 has a communication hole 141 formed therein.

Further, an inverted cup-shaped cover fitting 148 is assembled and fixed to the mass fitting 106. A stopper 150 is formed on the periphery of the opening of the cover fitting 148, and forms a mechanism for limiting the displacement of the mass fitting 106 in cooperation with the stopper 118 of the bracket 114. The bottom wall portion of the cover fitting 148 is spaced above the partition plate 146 while maintaining a space between the bottom fitting and the central recess at the axially upper end surface of the mass fitting 106. Thereby, the space on both sides in the axial direction of the mass metal fitting 106 is covered by the bottom wall portion of the cover metal fitting 148 and the supporting rubber elastic body 108, respectively, so that the inside of the cover metal fitting 148 is sealed from the external space. A closed chamber 152 is formed as an air chamber.

The closed chamber 152 is provided with the mass member 1.
The first divided sealed chamber 154 and the second divided sealed chamber 156 are divided into two by a partition plate 146 disposed in the axially upper part of FIG. The first divided sealed chamber 154 on the side of the mass fitting 106 and the second divided sealed chamber 156 on the bottom side of the cover fitting 148 are sealed from the external space. There, the communication hole 1 is formed in the partition plate 146.
41, the two divided sealed chambers 1 are provided.
54 and 156 are communicated with each other, and the communication hole 141 is provided.
The orifice passage 15 as a ventilation orifice which allows the flow of gas between the two divided sealed chambers 154 and 156
8 are formed. The orifice passage 158
Is small in diameter so that the resonance frequency of the air to be circulated is sufficiently higher than the vibration frequency for vibration isolation.

A through hole 160 is formed in the bottom wall of the cover fitting 148, and a vent filter 84 is provided in the through hole 160. The packing 85 is narrowly pressurized between the vent filter 84 and the cover fitting 148, whereby the through hole 160 is closed in a fluid-tight manner. Then, similarly to the first embodiment, the vent filter 84 can substantially completely prevent water or foreign matter from entering the sealed chamber 152 from the external space, and secures air permeability to generate the sealed chamber 152. The pressure change is released to the external space so that it can be maintained at substantially the atmospheric pressure.

Accordingly, the vibration damper 1 having the above-described structure is provided.
In 02, when a power supply line is connected to the power supply connector 111 and power is supplied to the coil 110 from the outside via the lead wire 111, the coil 110 and the mass metal fitting 106 forming a magnetic path are connected to each other in relation to the magnetic field existing in the gap 136. An electromagnetic force in the axial direction (vertical direction) is generated between the coils 110. When an alternating current or a pulsating current is applied to the coil 110, an exciting force is exerted between the coil 110 and the mass member 106 by the electromagnetic force. Becomes Therefore, by controlling the supply current to the coil 110 based on the reference signal corresponding to the vibration to be damped in the vibrating body, the vibration to be damped to the vibrating body is actively reduced. It is possible to exert an exciting force. In this case, in particular, since the vibration damper 102 forms one vibration system by the supporting rubber elastic body 108 and the mass metal fitting 106, the natural frequency of this vibration system is determined by the vibration frequency to be damped. By tuning to correspond to
By utilizing the resonance action of the vibration system, a large excitation force is exerted on the vibrating body with small power consumption, and an efficient vibration damping effect can be obtained.

Further, in the vibration damper 102 of the present embodiment, the through hole 160 is formed in the bottom wall portion of the cover fitting 148 which is a part of the wall defining the closed chamber 152, and the through hole 160 is formed. Is closed by a vent filter 84 including a gas permeable waterproof membrane as in the first embodiment, so that the vibration damping effect due to the intrusion of water or foreign matter from the external space into the closed chamber 152 can be reduced. Can be effectively avoided, and the durability of the vibration damper 102 can be improved. In addition, since the static pressure change generated in the sealed chamber 152 can be released to the external space,
The stable damping effect can be exhibited without the damping effect depending on the static pressure change generated in the closed chamber 152.

In addition, in the present embodiment, the closed chamber 1
52, a partition plate 146 is provided, and the partition plate 146 is formed with a communication hole 141 through the orifice passage 15.
8, the first divided sealed chamber 154 is formed.
Is applied through the orifice passage 158 to the second divided closed chamber. Therefore, for example, an active excitation force is applied to the mass metal fitting 106 by energizing the coil 110, and the displacement of the support rubber elastic body 108 which constitutes a part of the wall of the first divided sealed chamber 154 causes Even when a pressure change is caused in one of the divided sealed chambers 154, when the pressure change is transmitted to the vent filter 84, the orifice passage 158 allows the second divided sealed chamber 1.
Since the transmission of the pressure change to 56 can be prevented or buffered, the pressure change transmitted to the vent filter 84 disposed in the second divided sealed chamber 156 can be suppressed, It is possible to improve the durability of the gas permeable waterproof film used for the vent filter 84, and it is possible to obtain more stable gas permeable and waterproof properties.

Therefore, in such a vibration damper 102, the durability of the electromagnetic drive means, and furthermore, the durability of the vibration damper 102 can be effectively improved, and the exciting force generated by the electromagnetic drive means can be further reduced. As a result, it is possible to stably obtain, and thus, it is possible to efficiently maintain the desired anti-vibration characteristics for a long period of time.

Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention is not to be construed as being limited by the specific description in these embodiments. Absent.

For example, in the first embodiment, the vent filter 84 is provided for the closed chamber 62 provided behind the diaphragm 38, but the vent filter 84 is used as the air chamber with the equilibrium chamber 46 as the air chamber. 46 may be provided.
In this case, the vent filter 8 in the closed chamber 62 is used.
4 need not necessarily be provided.

The specific structure of the actuator provided in the closed chambers 62 and 152 is not limited at all. For example, various well-known actuators such as an actuator using a piezoelectric blocking or magnetostriction blocking degree are used. Any of them can be adopted.

The arrangement, specific shape and number of the vent filters 84 provided for the sealed chambers 62 and 152 are determined in consideration of the required waterproofness, cost, and manufacturability. It is appropriately set and is not particularly limited.

Furthermore, the number and specific shape of the orifice passages 158 formed in the partition plate 146 are not limited, and by setting them to appropriate cross-sectional areas and lengths, a desired frequency can be obtained. It is possible to tune.

Further, in the second embodiment, the leaf spring 1 forming the elastic support in cooperation with the support rubber elastic body 108 is used.
The number, shape, etc. of 40 are required for the spring characteristics and cost,
It is appropriately set in consideration of manufacturability and the like, and it is also possible to employ elastic supporting means such as a coil spring instead of such a leaf spring 140.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements, and the like can be made, and any such embodiments can be carried out without departing from the spirit of the present invention. It goes without saying that they are included in the range.

【The invention's effect】

As is apparent from the above description, in the vibration isolator and the actuator for the vibration isolator having the structure according to the present invention, the air chamber provided in a sealed state with respect to the external space is provided with a gas permeable waterproof membrane. By communicating with the external space through the air chamber, air permeability and waterproofness in the air chamber can be achieved at the same time.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an engine mount according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a vent filter employed in the engine mount shown in FIG.

FIG. 3 is a longitudinal sectional view showing a vibration damper as a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Engine mount 12 1st support fitting 14 2nd support fitting 32 Diaphragm 34 Rubber elastic body 38 Vibration plate 40,108 Support rubber elastic body 44 Main liquid chamber 46 Equilibrium chamber 48 Working air chamber 54 Orifice passage 62, 152 Closed chamber 64 electromagnetic drive means 84 vent filter 94 filter 102 damper 104 mounting bracket 106 mass bracket 110 coil 112 permanent magnet 146 partition plate 148 cover bracket 154 first divided sealed chamber 156 second divided sealed chamber 158 orifice passage

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Yoshihiko Hagino 3-1, Higashi 3-chome, Komaki City, Aichi Prefecture F-term (reference) 3D035 CA05 CA21 CA23 3J047 AA03 AB01 CA02 CC02 CC04 CD11 FA02 FA03 3J048 AA03 AB07 AC04 BA02 BB05 BB06 BE03 BF02 BF12 CB22 DA01 EA07 EA13

Claims (8)

[Claims] 1. An anti-vibration system in which an air chamber closed to an external space is provided on one side of a displacement member which is deformed or displaced by an exciting force passively or actively applied at the time of vibration input. A vibration isolator, wherein the air chamber is communicated with an external space via a breathable waterproof membrane. 2. A first mounting member attached to one member connected to the vibration-proof connection and a second mounting member attached to the other member connected to the vibration-proof connection. At least, a part of the wall is formed of the main rubber elastic body to form a pressure receiving chamber in which an incompressible fluid is sealed, and a part of the wall is formed of an easily deformable flexible film. By forming an equilibrium chamber filled with an incompressible fluid and providing an orifice passage communicating the pressure receiving chamber and the equilibrium chamber with each other, the flexible member constitutes the displacement member. The vibration isolator according to claim 1, wherein the air chamber is formed on a side opposite to the equilibrium chamber. 3. A first mounting member attached to one member connected to the vibration-proof connection and a second mounting member attached to the other member connected to the vibration-proof connection. At least, a part of the wall is constituted by the main rubber elastic body to form a fluid chamber in which an incompressible fluid is sealed, and another part of the wall of the fluid chamber is connected to the second mounting portion. By configuring the movable member so as to be displaceable with respect to the member, the movable member is configured with the movable member, and the air chamber is formed on the opposite side of the movable member from the fluid chamber. The vibration isolator according to claim 1 or 2, further comprising a vibration unit that applies a vibration force to the movable member to actively vibrate. 4. The vibration isolator according to claim 3, wherein said vibration means is accommodated and arranged in said air chamber. 5. A sub-vibration system is constructed by elastically connecting a mass member having a predetermined mass to a support member attached to a vibration member to be subjected to vibration isolation via an elastic support so as to be relatively displaceable. A vibration means for forming the air chamber between the support member and the mass member and forming the displacement member by the elastic support member, while applying a vibration force to the mass member to actively vibrate, 2. The vibration isolator according to claim 1, wherein said vibration isolator is accommodated in said air chamber. 6. A partition wall for bisecting the air chamber,
On both sides of the partition wall, a first divided air chamber in which a part of a wall portion is constituted by the displacement member, and a second divided air chamber communicated with the external space via the breathable waterproof membrane. The fluid filled type vibration damping device according to any one of claims 3 to 5, further comprising a ventilation orifice that connects the first divided air chamber and the second divided air chamber to each other. 7. The fluid filled type vibration damping device according to claim 1, wherein a hydrophobic porous film of polytetrafluoroethylene which has been made porous by stretching is used as the breathable waterproofing film. 8. A vibration control device comprising: a permanent magnet and a coil member disposed so as to be relatively displaceable; and a vibration force based on a magnetic force or an electromagnetic force generated by energizing the coil member. In an actuator for an anti-vibration device that produces an active anti-vibration effect, a cover member that partitions an operation space including a relative displacement region between the permanent magnet and the coil member from an external space is provided, and the operation space is sealed. An actuator, wherein the air chamber is in a state, and the air chamber is communicated with an external space via a breathable waterproof film.