JP2000283214A - Vibrator for vibration isolating device and active vibration isolating device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibrator for a vibration isolating device obtaining vibrating force by using a permanent magnet and a coil, which can resolve problems such as degradation in durability due to repeat deformation of a lead wire for feeding to the coil, and degradation in energy efficiency or controlling accuracy due to increasing the weight of an output member by equipping the permanent magnet. SOLUTION: A pair of permanent magnet members 82, 83, 100, 102, 104 are axially arranged on a first side of an axial member 78 and a housing cylindrical member 80 arranged so relatively displace in the axial direction. On axially both sides of these permanent magnet members, magnetic poles which is opposite in direction are provided, and a coil member which increases the intensity of magnetic fields by the pair of the permanent magnet members 82, 83, 100, 102, 104 at one side and decreases at the other side is equipped. On a second side of the axial member 78 and the housing cylindrical member 80, a strong magnetic member 86 which is arranged within the magnetic field formed by the pair of the permanent magnet members 82, 83, 100, 102, 104, and on which axial driving force is exerted by the change in the intensity of the magnet field with energizing the coil member is equipped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator for a vibration isolator which exerts a vibrating force when employed in a vibration isolator which exhibits an active vibration isolating effect, and an active vibration isolator using such a vibration exciter. It is about.

[0002]

2. Description of the Related Art Conventionally, in order to reduce vibration in a member to be damped, conventionally, vibration damping means using a damping effect of a shock absorber, a rubber elastic body, or the like, and a spring effect of a coil spring, a rubber elastic body, or the like are generally used. Vibration isolation means are used, but all of them exert a passive vibration isolation action. For example, when the vibration characteristics to be damped are changed, sufficient vibration isolation is used. There was a problem that it was difficult to obtain a vibration effect. Therefore, in recent years, active vibration isolators that actively or destructively suppress vibration to be damped have been developed, and application to a vibration isolator mount, a vibration isolator bush, a vibration damper, and the like may be considered. It has become For example, those described in JP-A-61-220925 and JP-A-1-83742 are those.

[0003] By the way, an active vibration isolator requires a vibrator for generating vibration. In such a vibrator,
Excellent frequency control of the generated excitation force is required. Therefore, Japanese Patent Application Laid-Open No. 61-220925 and Japanese Utility Model Application Laid-Open No. 3-73
No. 741, JP-A-6-235438, JP-A-6-505676, etc., a permanent magnet is arranged on one member arranged to be relatively displaceable, and the other is arranged on the other member. It has been proposed to employ a vibrator in which a coil is arranged on a member and a vibrating force is generated between the two members by Lorentz force or electromagnetic force generated by energizing the coil. .

However, in these vibrators, it is necessary to mount either the coil or the permanent magnet to the output member which is vibrated and displaced by the electromagnetic force. Then, since the power supply lead wire to the coil is deformed each time vibration is applied, there is a problem that it is difficult to obtain sufficient durability. On the other hand, when a permanent magnet is attached to the output member, the output controllability is likely to be deteriorated due to the large weight of the permanent magnet, and power consumption and heat generation tend to be problems because large drive power is required. .

[0005]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to prevent deformation of a power supply lead wire to a coil and to provide a permanent Provided is a novel structure of an electromagnetic vibration isolator for a vibration isolator having a novel structure capable of avoiding drastic weight increase of an output member due to a magnet and achieving both excellent durability and light weight of the output member. Is to do.

Further, the present invention is constituted by using a vibrator for a vibration isolator having a structure according to the present invention as described above, and an active vibration isolating effect based on the vibrating force of the vibrator is advantageous. It is another object of the present invention to provide an active vibration isolator which can be exhibited stably and stably.

[0007]

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. Further, aspects or technical features of the present invention are described in the entire specification and the drawings without being limited to those described below.
Alternatively, it should be understood that the present invention is recognized based on the inventive concept that can be grasped by those skilled in the art from the description thereof.

[0008] A first aspect of the present invention is as follows: (a) a shaft member;
(B) a housing cylinder member which is arranged outwardly in a direction perpendicular to the axis of the shaft member so as to be axially displaceable relative to the shaft member; and (c) magnetic poles are set on both sides in the axial direction. At least one pair of permanent magnet members fixedly disposed on one of the shaft member and the housing tubular member in a state where the magnetic poles are arranged in the axial direction so that the polarities of the magnetic poles are opposite to each other. And (d) a pair of magnetic fields respectively formed by the pair of permanent magnet members which are fixedly disposed with respect to the pair of permanent magnet members and form a unidirectional magnetic field by energization. (E) fixedly disposed on one of the other side of the shaft member and the housing tubular member to increase the strength of one of the shaft members and decrease the strength of the other one of the shaft members. Formed by permanent magnets Was allowed to position within the magnetic field, the strength of the magnetic field formed by the permanent magnets which form them each pair,
A vibrator for a vibration isolator having a ferromagnetic member to which an axial driving force is exerted by being relatively changed by energizing the coil member.

In the vibrator for the vibration isolator having the structure according to the first aspect of the present invention, a pair of magnetic fields are formed by the magnetic pole portions of the pair of permanent magnet members arranged in the axial direction. At the same time, the relative strength of the pair of magnetic fields is changed by energizing the coil member. As a result, the magnitude of the magnetic force exerted on the ferromagnetic member by the permanent magnet member is changed on both sides in the axial direction, and the ferromagnetic member has an amount corresponding to the relative strength generated by the pair of magnetic fields. Are displaced in the axial direction. Therefore, by controlling the energization of the coil member and changing the relative strength of the pair of magnetic fields, the displacement force applied to the ferromagnetic member is changed, and the permanent magnet member, the coil member, and the ferromagnetic member are changed. , In other words, an axial displacement force can be exerted between the shaft member and the housing cylinder member.

[0010] In the vibrator according to this aspect, since both the permanent magnet member and the coil member are mounted on one of the shaft member and the housing cylinder member, the vibrator is used. When assembling to the vibration isolator, of the shaft member and the housing cylindrical member, the member on which the permanent magnet member and the coil member are mounted is fixedly attached to the vibration isolator, and the member on which the ferromagnetic member is mounted is removed. By using an output member that can be vibrated and displaced, the deformation of the power supply lead wire to the coil member during operation can be completely prevented, and the weight of the output member due to the permanent magnet can be avoided. Thus, a vibration exciter for a vibration isolator having excellent durability and having a lightweight output member and exhibiting excellent controllability and energy efficiency can be advantageously realized.

In the vibrator according to this aspect, at least one pair of permanent magnet members is sufficient as a pair, and two or more pairs of permanent magnet members can be employed. Further, the coil member may be any member that can apply a magnetic field in one direction to the pair of permanent magnet members, and may be configured by a coil that is individually arranged for each pair of permanent magnets and forms a pair. , And a single coil that applies a magnetic field to a pair of permanent magnets. Furthermore, the ferromagnetic member may be formed of a ferromagnetic material such as iron, and may have various shapes and structures to which a magnetic force can be exerted by each pair of permanent magnets.
A movable iron core-shaped ferromagnetic member disposed in the center holes of the permanent magnet member and the coil member, each having a hollow solenoid structure, so as to be axially displaceable on the central axis of the permanent magnet member and the coil member. It is possible to adopt a member, or it is arranged to be axially spaced and opposed to a permanent magnet member and a coil member formed with an electromagnet structure, and to approach / change by a change in magnetic attraction by the permanent magnet member. It is also possible to employ an adsorbent-like ferromagnetic member arranged so as to be relatively displaceable in the separating direction.

According to a second aspect of the present invention, there is provided a vibration isolator for a vibration isolator having the structure according to the first aspect, wherein the vibration is applied between the shaft member and the housing cylinder member and between the two members. While preventing relative displacement in the direction perpendicular to the axis of
It is characterized in that a guide mechanism that allows relative displacement of the two members in the axial direction is provided. If such a guide mechanism is employed, the shaft member and the housing cylinder member are coaxially positioned relative to each other while allowing relative displacement in the axial direction, thereby increasing the operation of the vibrator, that is, increasing the generated vibration force. And stabilization becomes possible. In particular, when the magnetic pole portion of the permanent magnet member and the ferromagnetic member are employed in combination with a structure in which the magnetic pole portion and the ferromagnetic member are opposed to each other in a direction perpendicular to the axis, the distance between the facing surfaces of the magnetic pole portion and the ferromagnetic member is stabilized. Since it can be set small and sufficiently small, the magnetic force exerted between the permanent magnet and the ferromagnetic member, and hence the generated excitation force, can be obtained more efficiently.

The guide mechanism is, for example, a sliding sleeve which is fixedly supported by a housing tubular member and guides the shaft member slidably in the axial direction. Adopting a leaf spring having an annular plate shape that spreads at right angles, fixing the shaft member to the inner peripheral edge, and fixing the housing cylindrical member to the outer peripheral edge,
A configuration in which the components are axially separated from each other can be suitably adopted. If such a leaf spring is adopted, the shaft member and the housing cylinder member are set to a neutral position in the axial direction while the coil member is not energized based on the elasticity of the leaf spring. The position can be advantageously retained in a restoring manner, and a more stable vibration operation can be realized. More preferably, a plurality of leaf springs are disposed apart from each other in the axial direction, whereby the shaft member and the housing cylinder member can be more stably held coaxially.

According to a third aspect of the present invention, there is provided a vibration isolator for a vibration isolator having a structure according to the first or second aspect, wherein an axial direction relative to the shaft member and the housing cylindrical member is set. It is characterized in that a stopper means for limiting the amount of displacement is provided. If such a stopper is employed, the relative displacement between the permanent magnet member and the ferromagnetic member is reduced more than necessary. Therefore, even when an impact force or the like is input to the vibration isolator, the vibration can be reduced. In particular, the operation of the vessel can be stabilized, and in particular, the shaft member and the housing cylinder member are set at a constant relative neutral position in the axial direction by balancing the acting magnetic force on the ferromagnetic member by the pair of permanent magnet members. When restoring, restoration to the neutral position can be advantageously and stably realized. In addition, as such a stopper mechanism, for example, a contact surface that is axially separated from and opposed to each other in the axial direction is formed on the shaft member side and the housing cylinder member side via a cushioning member such as a rubber stopper. A structure in which the relative displacement in the axial direction between the two members is limited in a buffering manner by the contact of the contact surfaces via the buffer member is preferably employed.

Further, a fourth aspect of the present invention is a vibration isolator for a vibration isolator having a structure according to any one of the first to third aspects, wherein the pair of permanent magnet members are each The inner peripheral surface of the permanent magnet member is fixed to the housing cylindrical member in an annular shape extending in the circumferential direction, and both magnetic poles of the permanent magnet members are set apart from each other in the axial direction on the inner peripheral surface of each permanent magnet member. Along with forming the coil member by disposing a coil between the two magnetic poles in the axial direction of each of the permanent magnet members, a cylindrical portion is provided for the ferromagnetic member, and the cylindrical portion is formed. It was arranged coaxially with each permanent magnet member, and the outer peripheral surface of the cylindrical portion was opposed to the inner peripheral surface where the magnetic poles were set in each permanent magnet member with a gap in the radial direction. That is the feature. According to this embodiment, a vibrator having a substantially solenoid structure can be advantageously realized, and the permanent magnet member and the ferromagnetic member, and further, the shaft member can be advantageously compared with the case where an electromagnet structure or the like is employed. It is possible to easily secure the stroke amount and the control accuracy of the housing cylinder member in the axial direction.

According to a fifth aspect of the present invention, there is provided a vibration isolator for a vibration isolator having a structure according to the fourth aspect, wherein the ferromagnetic members are arranged such that the axial lengths thereof are arranged in the axial direction. The length of the pair of permanent magnet members is smaller than the entire length in the axial direction. In such an embodiment, a larger axial driving force can be efficiently obtained between the permanent magnet member and the ferromagnetic member.

Further, a sixth aspect of the present invention is a vibration isolator for a vibration isolator having a structure according to any one of the first to fifth aspects, wherein each pair is energized by energizing the coil member. An auxiliary magnet for increasing the axial driving force exerted on the ferromagnetic member in cooperation with the relative strength of the magnetic field generated by the permanent magnet is fixed to the ferromagnetic member. And In this embodiment, a greater axial relative driving force can be obtained between the permanent magnet member and the ferromagnetic member, and thus between the shaft member and the housing cylinder member. In addition, the auxiliary magnet fixed to the ferromagnetic member assists the magnetic force of the permanent magnet member and can be at least smaller than the permanent magnet, so that the problem of weight increase in the ferromagnetic member can be advantageously avoided. .

According to a seventh aspect of the present invention, there is provided a fluid chamber in which an incompressible fluid is sealed, wherein a part of a wall portion is formed of a main rubber elastic body elastically deformed by input vibration. By configuring another part of the wall of the fluid chamber with a displaceable vibration member, and vibrating the vibration member,
In an active vibration isolator capable of controlling the internal pressure of the fluid chamber, a vibration isolator vibrator having a structure according to any of the first to sixth aspects is adopted, In the vibrator, an axial relative displacement force generated between the shaft member and the housing cylindrical member is applied to the vibrating member to vibrate, while a part of the wall portion is easily deformed. An active vibration isolator comprising a flexible film, forming an equilibrium chamber filled with an incompressible fluid, and providing a fluid communication passage connecting the equilibrium chamber to the fluid chamber. .

According to this embodiment, the active force capable of effectively and precisely controlling the exciting force to the exciting member, and thus the internal pressure of the fluid chamber, over a high frequency range. A type anti-vibration device can be advantageously realized. Further, in this aspect, even when a static load is input under the mounted state of the vibration isolator, the pressure change of the fluid chamber due to the static load causes the fluid flow from the fluid chamber to the equilibrium chamber through the fluid communication passage. As a result, the initial load applied to the vibrating member and the vibrator can be advantageously reduced or avoided, and the vibrator can stably move the vibrating member. It is possible to stably obtain the excitation operation and, consequently, the intended active vibration damping effect irrespective of the action of the static load or the magnitude thereof.

It is desirable that the fluid communication passage be substantially closed in a frequency range in which a vibration damping effect is to be obtained based on the control of the internal pressure of the fluid chamber by the vibration of the vibration member. This can be advantageously realized by setting the value of the ratio of the cross-sectional area of the fluid communication passage: A to the length of the passage: L: A / L sufficiently small. Also, by setting an appropriate A / L value for this fluid communication passage,
It is also possible to obtain a passive vibration damping effect based on the resonance action of the fluid caused to flow through the fluid communication passage at the time of vibration input. Particularly preferably, the passive vibration damping effect based on the resonance action of the fluid caused to flow through the fluid communication passage is reduced to vibration in a lower frequency range than the vibration exerting the vibration damping effect based on the internal pressure control of the fluid chamber. The value of A / L of the fluid communication passage is tuned so as to be exerted on the fluid communication passage. As a result, both the active vibration damping effect based on the internal pressure control of the fluid chamber and the passive vibration damping effect based on the resonance effect of the fluid flowing through the fluid communication passage can be more advantageously exerted.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 as a first embodiment of an active vibration isolator according to the present invention. This engine mount 10
Has a structure in which a first mounting bracket 12 and a second mounting bracket 14 which are spaced apart and opposed to each other are elastically connected by a main rubber elastic body 16, and the first mounting bracket 12 is an automobile. The second mounting bracket 14 is fixed to the body side of the vehicle with a bolt or the like on the power unit side, and is interposed between the power unit and the body,
The power unit is designed to support the body against vibration. In such a mounted state, a static power unit load is applied between the first mounting bracket 12 and the second mounting bracket 14 in the substantially vertical direction in the drawing. In addition to the input in the direction in which the two mounting brackets 14 are opposed to each other (in the direction of the center axis of the mount), the main vibration to be damped is also input in substantially the same direction as the load of the power unit. In the following description, the up-down direction refers to the up-down direction in FIG. 1 in principle.

More specifically, the first mounting bracket 12 includes a substantially cup-shaped cup metal 17 and a substantially disk-shaped lid metal 1.
8. The cup fitting 17 includes a tapered cylindrical peripheral wall portion 20 that expands toward the opening side, and a flange-like portion 22 that extends radially outward at an opening peripheral edge portion. Is integrally formed with an annular caulking portion 24. Then, the cover fitting 18 is overlapped with the opening of the cup fitting 17, and the outer peripheral edge of the cover fitting 18 is fixed by caulking with the flange-shaped portion 22 and the caulking portion 24, and the opening of the cup fitting 17 is closed The first mounting member 12 having a hollow structure is formed by being covered in a fluid-tight manner. A mounting bolt 25 protruding upward is fixed at the center of the lid fitting 18 so that the first mounting fitting 12 is fixedly attached to a power unit (not shown) by the mounting bolt 25. It has become.

A diaphragm 26 made of an easily deformable thin rubber film as a flexible film is accommodated in the hollow inside of the first mounting member 12. The diaphragm 26 has its center portion slackened so as to be easily deformed, and the outer peripheral edge portion is held by the caulking portion of the cup fitting 17 and the lid fitting 18 so that the first mounting bracket 1 is held.
The two hollow interiors are arranged vertically and fluid-tightly in two. Accordingly, an equilibrium chamber 28 in which an incompressible fluid is sealed is formed between the diaphragm 26 and the cup fitting 17 in the hollow interior of the first mounting fitting 12, and the diaphragm 26 and the lid are formed. An air chamber 30 that allows deformation of the diaphragm 26 is formed between the metal fittings 18. In addition, any of water, alkylene glycol, polyalkylene glycol, silicone oil, and the like can be used as the sealed fluid. In the present embodiment, in particular, in order to effectively obtain a vibration damping effect based on a fluid flow action described later. In this case, a low-viscosity fluid of 0.1 Pa · s or less is suitably used. Further, the air chamber 30 may be communicated with an external space.

On the other hand, the second mounting member 14 includes an upper cylindrical member 32 and a lower cylindrical member 3 each having a large-diameter, substantially cylindrical shape.
4. The upper cylindrical metal part 32 is a tapered cylindrical part 36 whose substantially upper half in the axial direction expands upward, and has a substantially annular ring that expands radially outward in the axially lower opening part. A plate-shaped step portion 40 is integrally formed, and a caulking portion 42 extending in the axial direction is integrally formed on the outer peripheral edge of the step portion 40. On the other hand, the lower cylinder fitting 34 is formed integrally with a substantially annular plate-shaped upper flange-shaped portion 44 and a lower flange-shaped portion 46 which respectively extend outward in the radial direction at the upper and lower opening peripheral edges in the axial direction. The upper and lower cylindrical fittings 32 and 34 are overlapped with each other in the axial direction, and the lower flange-like portion 46 of the lower cylindrical fitting 34 is formed with the step portion 40 and the caulking portion 42 of the upper cylindrical fitting 32.
The upper and lower tubular fittings 32 and 34 are fixed to each other by being swaged and fixed so that the second fitting 14 has a large-diameter cylindrical shape as a whole.
Although not explicitly shown in the drawings, the lower flange-shaped portion 46 of the lower cylindrical fitting 34 is provided with a mounting hole, a mounting bolt, and the like for fixing the second mounting fitting 14 to the body of the automobile. I have.

The first mounting member 12 is disposed so as to be axially above the second mounting member 14 so as to face each other on substantially the same central axis. A main rubber elastic body 16 is interposed between opposing surfaces of the metal fitting 12 and the second mounting metal 14, and the first mounting metal 12 and the second mounting metal 14 are elastically connected by the main rubber elastic body 16. Have been. The main rubber elastic body 16 has a substantially truncated conical shape, and a cup fitting 17 constituting the first mounting fitting 12 is superimposed on the small diameter side end face,
The outer peripheral surface of the tapered cylindrical portion 36 of the cup fitting 17 is vulcanized and adhered to the main rubber elastic body 16 in a state of entering the inside of the main rubber elastic body 16. A second mounting bracket 14 is provided on the outer peripheral surface of the large-diameter end of the main rubber elastic body 16.
Are overlapped, and the inner peripheral surface of the tapered tubular portion 36 is vulcanized and adhered. In short, the main rubber elastic body 16 is
And an upper cylinder fitting 32 are integrally formed. The space between the cup fitting 17 and the upper opening of the upper cylinder fitting 32 is fluid-tightly closed by the main rubber elastic body 16. The inner peripheral surface of the upper cylindrical fitting 32 has a stepped portion 4.
A thin seal rubber layer 48 including the lower surface of the main rubber elastic body 16 is formed integrally with the main rubber elastic body 16. In addition, the main rubber elastic body 16 has an upper cylindrical fitting 32 at the large diameter end face.
A large-diameter circular recess 50 that opens into the inside is formed, and the bottom wall 52 of the cup fitting 17 is formed at the bottom of the circular recess 50.
Is exposed.

A partition plate 54 and a vibrating member 56 are provided in the hollow interior of the second mounting member 14 in a housed state. The partition plate 54 is formed of a hard material such as a metal,
It has a thin, generally circular disk shape, and its outer peripheral edge is held between the caulking portions of the upper and lower cylindrical fittings 32, 34,
It extends in the direction perpendicular to the axis and is arranged so as to partition between the upper and lower cylindrical fittings 32 and 34. The vibrating member 56 is formed of a hard material such as a metal and has an inverted cup shape, and a supporting cylindrical metal fitting 60 formed of a hard material such as a metal is provided on an outer peripheral side of the vibrating member 56. Are arranged substantially coaxially and spaced apart in the radial direction. A connecting rubber 58 formed of a rubber elastic body having a substantially annular shape is interposed between the outer peripheral surface of the cylindrical wall portion of the vibrating member 56 and the inner peripheral surface of the supporting cylindrical member 60, The inner peripheral surface of the connecting rubber 58 is vulcanized and adhered to the cylindrical wall of the vibrating member 56, and the outer peripheral surface of the connecting rubber 58 is vulcanized and adhered to the support cylinder 60, so that the vibrating members The support cylinder 60 is elastically connected to the support cylinder 60 by a connection rubber 58. In addition, the support cylinder fitting 60 is a thin stepped cylinder in which a small-diameter portion 62 is formed integrally on the lower side in the axial direction and a large-diameter portion 64 is formed integrally on the upper side in the axial direction, with a step portion formed in the middle portion in the axial direction. It has a shape, and a flange-shaped support portion 66 is formed integrally with the periphery of the opening of the large diameter portion 64. The connecting rubber 58 is vulcanized and bonded to the inner peripheral surface of the small-diameter portion 62, while the support portion 66 is
The partition plate 54 is superimposed on the outer peripheral edge of the partition plate 54.
At the same time, the connection rubber 58 and the bottom wall of the vibration member 56 are assembled in such a manner as to be spread in the direction perpendicular to the axis by being clamped between the caulking portions of the upper and lower cylindrical fittings 32 and 34. In addition, by attaching the vibration member 56 in this manner, the opening on the axially lower side of the second mounting member 14 is
The vibrating member 56, the connecting rubber 58, and the support cylinder 60 are fluid-tightly closed.

Thus, on the upper side of the partition plate 54, a main liquid chamber 68 in which a part of the wall is formed of the main rubber elastic body 16 and in which an incompressible fluid is sealed is formed. On the other hand, on the lower side of the partition plate 54, a part of the wall portion is constituted by the vibration member 56, and a sub-liquid chamber 70 in which an incompressible fluid is sealed is formed. That is, the main liquid chamber 68
In the meantime, when a vibration is applied to the first mounting member 12 and the second mounting member 14, the internal pressure fluctuation is generated based on the elastic deformation of the main rubber elastic body 16, while the sub-liquid chamber 70 The inner pressure is controlled by displacing the vibration member 56 by a vibration device 72 described later. A through hole 74 having an inner diameter smaller than the outer diameter of the vibrating member 56 is formed at the center of the partition plate 54. The through hole 74 allows the main liquid chamber 68 and the sub liquid chamber 70 to pass through.
Are communicated with each other. Thus, a pressure change in the sub liquid chamber 70 due to the vibration displacement of the vibration member 56 is transmitted to the main liquid chamber 68 based on the fluid flow through the through hole 74. Then, as is well known, the vibration member 56 is vibrated with a vibration force corresponding to the frequency and amplitude of the vibration to be damped, and the pressure of the main liquid chamber 68 is actively controlled to thereby reduce the input vibration. An offset vibration damping effect can be obtained or a dynamic spring constant reduction effect of the engine mount 10 can be obtained, so that an active vibration damping effect is exhibited. As is clear from this,
In the present embodiment, a part of the wall is constituted by the main rubber elastic body 16 and the vibrating member 56 by the main liquid chamber 68 and the sub-liquid chamber 70, and a fluid chamber whose internal pressure can be controlled by the displacement of the vibrating member 56. Is configured.

Particularly preferably, the resonance action of the fluid caused to flow through the through-hole 74 is exerted in a vibration frequency range to be damped such as low-order vibration or high-order vibration of idling or running noise. The passage cross-sectional area and the passage length of the through hole 74 are tuned so that the pressure transmission efficiency from the chamber 70 to the main liquid chamber 68 is advantageously ensured. Also, the connecting rubber 58
The vibrating member 5 is driven by a vibrating force applied from the vibrator 72.
6 is designed to have an elastic deformability that can be sufficiently displaced, and a rigidity that does not allow pressure to escape due to swelling deformation or the like easily due to a change in pressure of the sub-liquid chamber 70. In particular, it is desirable that the connecting rubber 58 has elasticity so that the vibration member 56 can be restored to a fixed initial position in the axial direction.

A communication small hole 76 is formed at the center of the bottom wall 52 of the cup fitting 17 constituting the first mounting member 12, and the main liquid chamber 68 is formed through the communication small hole 76.
And the equilibrium chamber 28 are communicated with each other, and both chambers 68, 2
Fluid flow between 8 is allowed. Then, when the power unit load is applied and the main rubber elastic body 16 is elastically deformed under the mounted state of the engine mount 10 and the pressure of the main liquid chamber 68 is increased,
Since the fluid flows from the main liquid chamber 68 to the equilibrium chamber 28 through the small hole 76, the pressure change of the main liquid chamber 68 is reduced or avoided as much as possible based on the capacity change allowance of the equilibrium chamber 28. As a result, the desired anti-vibration characteristics are stably exhibited.

Particularly preferably, the resonance action of the fluid caused to flow through the communication small hole 76 is exerted in a frequency range lower than the vibration required for the active vibration damping effect by the vibration of the vibration member 56. Based on the resonance effect of the fluid through the communication small hole 76, the passage cross-sectional area and the passage length of the communication small hole 76 are set so that the passive vibration-proof effect against low-frequency vibration such as shake is effectively exerted. Is tuned.

Further, a vibrator 72 is mounted on the mount body having the above-described structure with respect to the second mounting bracket 14, and the vibrator 72 allows the vibrating member 5 to be mounted.
6 is reciprocated in the axial direction.

In the vibrator 72, a housing tube fitting 80 as a housing tube member is disposed on substantially the same central axis so as to be spaced radially outward of a shaft bolt 78 as a shaft member. A magnetic body 86 as a ferromagnetic member is disposed in a magnetic field formed by a pair of permanent magnets 82 and 83 fixedly mounted on the housing cylinder 80 and a pair of coils 84 and 85. The magnetic body 86 is fixedly attached to the shaft bolt 78,
The relative displacement force in the axial direction is exerted between the shaft bolt 78 and the housing cylindrical member 80 by changing the strength of the magnetic field when the coils 84 and 85 are energized, and thus the strength of the magnetic force exerted on the magnetic body 86. It has become.

More specifically, the shaft bolt 78 has a rod shape that extends in the axial direction in the opposite direction with the bolt head at the lower end and extends over the entire length in the axial direction on the outer peripheral surface. Extending fixing sleeve 88 and a plurality of fixing rings 90
However, it is extrapolated. The upper end in the axial direction of the shaft bolt 78 is screwed and fixed to the center of the bottom wall of a connection fitting 92 having a substantially thick cup shape.
By pinching it axially between 2 and the bolt head,
The fixing sleeve 88 and each fixing ring 90 are fixedly attached to the shaft bolt 78, respectively. A cylindrical magnetic body 86 made of a ferromagnetic material such as iron is extrapolated and arranged at the center of the shaft bolt 78, and is integrally formed at an axially upper opening of the magnetic body 86 so as to be formed in a radial direction. An annular plate-shaped mounting portion 94 extending inward is provided with a fixing sleeve 88.
And the fixing ring 90 in the axial direction, the magnetic body 86 is fixedly assembled to the shaft bolt 78 in a state where the magnetic body 86 is coaxially spaced apart radially outward of the shaft bolt 78. Have been.

On the other hand, the housing cylinder 80 has a cylindrical shape having a diameter sufficiently larger than the shaft bolt 78 and the magnetic body 86, and a magnet / coil unit 96 is fitted into the hollow interior of the housing cylinder 80. It is fixedly assembled. The magnet / coil unit 96 has two cylindrical permanent magnets 82 and 83 and a substantially thick annular plate with respect to a cylindrical outer peripheral holder 98 made of a nonmagnetic material such as synthetic resin or aluminum. Three yokes 100, 102, and 104 made of a ferromagnetic material are alternately overlapped and inserted in the axial direction, and are formed on both sides in the axial direction at openings on both sides of the housing cylinder 80. It is fixedly attached to the housing cylinder 80 by being clamped by the caulking portion 110 via the ring-shaped spacer 106. Here, each of the permanent magnets 82 and 83 is disposed along the inner peripheral surface of the outer peripheral holder 98, and both magnetic poles are formed on both sides in the axial direction.
Are set opposite to each other so that the ends of the two permanent magnets 82 and 84 that face each other in the axial direction have the same polarity (in the illustrated embodiment,
Both are N poles). Each yoke 100, 10
Each of the yokes 100, 102, and 10 is disposed so as to project radially inward from the inner peripheral surface of the outer peripheral holder 98, and is disposed adjacent to each other in the axial direction.
The two permanent magnets 82 and 84 are disposed between the opposing surfaces 2 and 104 so as to be axially sandwiched between their outer peripheral edges. As a result, in the yokes 100 and 104 on both the upper and lower sides, the same magnetic pole (in the illustrated embodiment, both S poles) are formed on the inner peripheral edge, and the inner yoke 102 on the central yoke 102 is formed. Another magnetic pole (N pole in the illustrated embodiment) is formed in the portion. In short, in the present embodiment, the two permanent magnets 82,
84 and three yokes 100, 102, 104,
Magnetic poles are set on both sides in the axial direction to form a pair of permanent magnet members arranged in the axial direction.

Further, between the opposing surfaces of the yokes 100 and 102 and 102 and 104 arranged adjacent to each other in the axial direction, coils 84 and 85 are disposed on the inner peripheral sides of the permanent magnets 82 and 83, respectively. It is assembled in a state of being accommodated between the yokes 100 and 102 and between the yokes 102 and 104, respectively. Each of the coils 84 and 85 has a lead wire 108 respectively.
Power is supplied through In short, two permanent magnets 82, 83 and three yokes 100, 102,
Two coils 84 and 85 are mounted on the pair of permanent magnet members formed at 104 between the two magnetic pole portions, and these coils 84 and 85 constitute a coil member. The inner diameter of the bobbin in each of the coils 84 and 85 is equal to the yoke 100, 102,
The inner diameter is substantially the same as the inner diameter 104.

A shaft bolt 78 to which a magnetic body 86 is attached is inserted into a hollow hole of a magnet / coil unit 96 assembled to the housing cylinder 80.
In addition, in the opening on both sides in the axial direction of the housing cylinder 80,
Metallic leaf springs 1 each having a thin annular plate shape
The inner peripheral edge is fixed to the shaft bolt 78 by a fixing sleeve 88 or a fixing ring 90, and the outer peripheral edge is fixed to the housing cylinder 80 by a spacer 106 or a caulking portion 110. As a result, it is assembled so as to straddle between the shaft bolt 78 and the housing cylinder 80. Thereby, the shaft bolt 7
8 and the housing cylinder 80 are prevented from relative displacement in the direction perpendicular to the axis by a pair of leaf springs 112 provided at both ends in the axial direction, and are axially moved based on the elastic deformation of the leaf springs 112. Are resiliently connected to each other and positioned on the same central axis in a state where relative displacement is allowable.

On the housing cylinder 80 side,
Each yoke 100, 102, 1 forming a magnetic pole portion
The inner diameter of the magnetic material 04 is the same as that of the magnetic material 8 attached to the shaft bolt 78.
6 is set slightly larger than the outer diameter of the yoke 100, 102, 104 so that the inner peripheral surface of each of the yokes 100, 102, 104 faces the outer peripheral surface of the magnetic body 86 with a small gap in the radial direction. Have been. Further, in the present embodiment, the magnetic body 8
6 has three yokes 100, 102, 10
4 is slightly shorter than the total axial length of the upper and lower ends of the magnetic pole portion.
A magnetic body 86 is provided at a central portion in the axial direction with respect to 104. In the magnet / coil unit 96, the axial thicknesses of the upper and lower yokes 100 and 104 are set to be substantially the same.
Numeral 6 has a substantially symmetrical structure with respect to the center line not only in the radial direction but also in the axial direction.

Then, the vibrator 7 having such a structure is provided.
2, a housing cylinder 80 is press-fitted and fixed to a substantially large-diameter cylindrical bracket 114;
, The housing cylinder 80 is fixedly attached to the second mounting bracket 14 (lower cylinder 34) constituting the mount body. On the other hand, the shaker 72
The shaft bolt 78 is assembled by press-fitting and fixing a connection fitting 92 screwed to the upper end of the shaft bolt 78 to the vibration member 56 constituting the mount body. As a result, the vibrator 72 is located axially below the second mounting bracket 14 and is disposed substantially on the same central axis as the second mounting bracket 14.

The bracket 114 has an outward flange-like portion 116 formed integrally with the upper opening in the axial direction.
The lower cylinder fitting 34 is fixed to the lower cylinder fitting 34 by being superimposed on the lower flange-shaped portion 46 and fixed by bolts with fixing bolts 118. The lower opening in the axial direction of the bracket 114 is covered with an easily deformable dust cover 120 formed of a thin rubber film. Further, a substantially annular plate-shaped stopper fitting 122 is provided at the axially upper opening of the housing tubular fitting 80, and the outer peripheral edge of the stopper fitting 122 is attached to the housing tubular fitting 80 by the spacer 106 and the caulking portion 110. It is clamped and fixed. The stopper fitting 122 has a central portion protruding upward in the axial direction, an inner peripheral portion protruding most upward in the axial direction, and is provided on the outer peripheral side of the connecting fitting 92 fixed to the upper end of the shaft bolt 78. The connecting metal fitting 9
2 and is opposed to the vibrating member 56 which is externally fitted and fixed in the axial direction.

In the present embodiment, as described above, the housing cylindrical member 80 of the vibrator 72 is fixedly supported by the second mounting member 14 and the shaft bolt 78 is connected to the vibrating member 5.
6 fixedly attached to the vibrator 7
In a state in which the mounting member 2 is mounted on the mount main body, almost any deformation occurs in each of the leaf springs 112 and 112 in the vibrator 72 and the connecting rubber 58 that elastically supports the vibrating member 56 in the mount main body. Each part size is set so that there is no such.

In the engine mount 10 having the above-described structure, when the coils 84 and 85 of the vibrator 72 are energized, the shaft bolt 78 of the vibrator 72 is energized.
An axial relative displacement force generated between the housing member 80 and the housing cylinder 80 is exerted on the vibration member 56, so that the vibration member 56 is vibrated and displaced.

That is, in this embodiment, each coil 8
4, 85 are supplied with electricity through the lead wire 108 in the same circumferential direction. First, as shown in FIG. 2, when current is supplied to each of the coils 84 and 85 in a clockwise direction when viewed from above in the axial direction, the coils 8 and 85 are energized.
By energizing the coils 4 and 85, a magnetic field is generated around the coils 84 and 85 in which the lines of magnetic force are directed downward on the inner peripheral side of the coils 84 and 85 and upward on the outer peripheral side. The magnetic field generated by energizing the coils 84 and 85 weakens the magnetic field in the opposite direction between the magnetic poles formed on the inner peripheral surfaces of the upper yoke 100 and the middle yoke 102 by the upper permanent magnet 82. On the other hand, the lower yoke 1
02 and the magnetic field in the same direction between the magnetic poles formed on the inner peripheral surfaces of the lower yoke 104 are strengthened. As a result, the upper yoke 10
0 and the magnetic force exerted on the upper portion of the magnetic body 86 between the magnetic poles of the middle yoke 102 and the lower yoke 10.
The magnetic body 86 moves toward the lower side in the axial direction with respect to the magnet / coil unit 96 so that the magnetic force exerted on the lower portion of the magnetic body 86 between the magnetic poles of the magnets 4 increases to obtain a larger magnetic flux density. Relative displacement.

Next, from this state, the coils 84, 85
When the power supply to the magnetic body 86 is stopped, the magnetic force applied to the upper portion of the magnetic body 86 between the magnetic poles of the upper yoke 100 and the middle yoke 102 and the magnetic force between the magnetic poles of the middle yoke 102 and the lower yoke 104 as shown in FIG. And the magnetic force exerted on the lower portion of the magnetic body 86 is equalized.
Due to the elasticity of 12, 112, the magnetic body 86 is restored to the neutral position located at the axial center portion with respect to the magnet / coil unit 96.

Thereafter, as shown in FIG. 4, when current is applied to each of the coils 84 and 85 in a counterclockwise direction when viewed from above in the axial direction, the coils 84 and 85 are energized.
Due to the power supply to the coils 84 and 85, the magnetic field lines directed upward on the inner peripheral side of the coils 84 and 85 and directed downward on the outer peripheral side of the coils 8 and 85
Spawn around 4,85. Then, the upper yoke 100 and the middle yoke 102 are driven by the upper permanent magnet 82 by a magnetic field generated by energizing the coils 84 and 85.
The magnetic field in the same direction between the magnetic poles formed on each inner peripheral surface of the inner yoke 102 is strengthened,
The magnetic field in the opposite direction between the magnetic poles formed on the inner peripheral surface of the lower yoke 104 is weakened. As a result, the middle yoke 102
The magnetic force exerted on the lower portion of the magnetic body 86 between the magnetic poles of the lower yoke 104 and the upper yoke 100 and the middle yoke 102
The magnetic body 86 is displaced relative to the magnet / coil unit 96 upward in the axial direction so that the magnetic force exerted on the upper portion of the magnetic body 86 between the magnetic poles becomes larger, and a larger magnetic flux density is obtained. I'm sullen.

Therefore, the direction of energization to the coils 84 and 85 is switched and controlled in accordance with the frequency of the input vibration to be damped, so that the shaft bolt 78 is displaced in the axial direction relative to the housing cylinder 80. Can do
Therefore, the vibration member 56 attached to the shaft bolt 78
At a frequency corresponding to the input vibration, it is possible to obtain a desired active vibration damping effect.

In the engine mount 10 having the above-described structure, the coils 84 and 85 of the vibrator 72 are fixed to the housing tubular fitting 80 fixedly mounted on the second fitting 14. Therefore, when the vibrator 72 is operated, an excessive force such as deformation on the lead wire 108 can be prevented from acting, and excellent durability can be realized.

In the engine mount 10,
In the vibrator 72, the permanent magnets 82 and 83
4, 85, since it is fixed to the housing tube fitting 80 fixedly attached to the second mounting fitting 14,
It is possible to reduce the mass of the movable portion that is displaced during the operation of the vibrator 72 without drastically lowering the output. As a result, the vibratory output by the vibrator 72 can be increased to a high frequency range. It is possible to control with high precision. In particular, in the present embodiment, the magnetic material 8 having a hollow structure is used.
By adopting No. 6, the control accuracy is further improved by further reducing the weight of the movable part.

Further, in the present embodiment, each permanent magnet member is formed in a concave groove shape which opens to the inner circumferential side and extends in the circumferential direction, and the magnetic poles are set on both inner circumferential edges which are separated from each other in the axial direction. In addition, since the coils 84 and 85 are disposed in a state of being accommodated in the concave grooves, a space for disposing the coils 84 and 85 is efficiently secured, and the coils 84 and 85 are efficiently disposed. There is also an advantage that the effect of adjusting the magnetic force of the permanent magnet member by energizing the power is more efficiently exerted.

In the present embodiment, the pair of leaf springs 112 can advantageously position the shaft bolt 78 and the housing cylinder 80 in the direction perpendicular to the axis, and the shaft bolt 78 can be used. The housing cylinder 80 is restored to the neutral position in the axial direction and is positioned and held, so that more stable operation can be realized. In addition, the relative displacement of the shaft bolt 78 and the housing cylinder 80 in the axial direction is not only the elasticity of the leaf spring 112 but also
Since the vibration member 56 is restricted by contact with the partition plate 54 and the stopper fitting 122, the operation stability is more advantageously realized, and the excessive deformation of the connecting rubber 58 is prevented, and the durability is improved. Improvement can also be achieved.

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.

Incidentally, another embodiment of the vibrator which can be suitably adopted in the engine mount 10 as in the above embodiment is shown in FIGS. 5 to 8 and a brief explanation will be added below. In the following description, members and parts having the same structure as the vibrator in the above embodiment are given the same reference numerals as those in the above embodiment in the drawings, and their details are described. Detailed description is omitted.

First, in the vibrator 126 shown in FIG. 5, the magnetic body 86 attached to the shaft bolt 78 is
Two auxiliary magnets 128, 129 are fixedly assembled. Each of these auxiliary magnets 128 and 129 has a cylindrical shape, and is arranged in the axial direction so that the magnetic field formed by the upper permanent magnet member and the magnetic field formed by the lower permanent magnet member are aligned. It is arranged so that it can be positioned inside and inside. Each of the auxiliary magnets 128 and 129 has both magnetic poles formed on both sides in the axial direction.
By being set opposite to each other, the ends of the two auxiliary magnets 128 and 129 that face each other in the axial direction have the same polarity. In particular, in the present embodiment,
Each yoke 100, 102, 10 constituting the permanent magnet member
The polarities of the auxiliary magnets 128, 129 are set so that the magnetic poles of the auxiliary magnets 128, 129 receive magnetic attraction with respect to the magnetic pole of No. 4.

In the vibrator 126 of this embodiment in which such auxiliary magnets 128 and 129 are provided on the magnetic body 86,
Since the permanent magnets 82 and 83 and the auxiliary magnets 128 and 129 cooperate to form a magnetic field having a higher magnetic flux density, the magnetic force as a restoring force for guiding the shaft bolt 78 to the neutral position with respect to the housing cylinder 80. Further, it is possible to obtain the exciting force more advantageously. Moreover, the auxiliary magnet 12
8, 129 can be small, so that the effect of improving the control accuracy by reducing the weight of the vibrating member can be sufficiently achieved.

Next, in the vibrator 130 shown in FIG. 6, the middle yoke 102, which is a single member in the vibrator 72 according to the first embodiment, is used for the upper coil 84. The middle yoke 132 and the middle yoke 134 for the lower coil 85 are divided and formed independently. Even when the permanent magnet member having such a structure is employed, any of the effects similar to those of the vibrator 72 according to the first embodiment can be effectively exhibited.

Further, in the vibrator 136 shown in FIG. 7, each of the vibrators 136 has a cylindrical shape in a state of being directly radially opposed to the outer peripheral surface of the magnetic body 86 fixed to the shaft bolt 78. The permanent magnet 136 and the permanent magnet 138 having
They are arranged in a state of being arranged in the axial direction, and are fixedly supported by the housing tube fitting 80. These permanent magnets 136 and 138 have both magnetic poles formed on both sides in the axial direction, as in the first embodiment, and have both permanent magnets 1.
By setting the polarities at 36 and 138 to be opposite to each other, the ends of the two permanent magnets 136 and 138 facing each other in the axial direction have the same polarity. In short, in the present embodiment, a pair of permanent magnet members is constituted by the single permanent magnets 136 and 138 without using a yoke or the like. Therefore, even when the permanent magnet member having such a structure is employed, the same effects as those of the vibrator 72 according to the first embodiment can be effectively exerted.

Further, in the vibrator 140 shown in FIG. 8, as in the vibrator 136 shown in FIG. 7, a single permanent magnet 136, 138 forms a pair of permanent magnet members. In addition, on the outer peripheral side of the two permanent magnets 136 and 138, both permanent magnets 136 and 138 are provided.
A coil member is constituted by one coil 142 disposed so as to straddle between 138. By employing one coil 142 that applies a magnetic field to each of the permanent magnet members in this manner, the same effect as that of the vibrator 72 according to the first embodiment can be effectively obtained. You can.

In each of the above-described embodiments, the ferromagnetic member is mounted on the shaft member side, while the permanent magnet member and the coil member are mounted on the housing cylinder member side. In the case where the housing cylinder member is fixed and can be vibrated and displaced as an output member, a configuration is adopted in which a permanent magnet member and a coil member are mounted on the shaft member side and a ferromagnetic member is mounted on the housing cylinder member side. Is done.

Further, the current supplied to the coil member may be any as long as it can change the magnetic field formed by the permanent magnet member. In addition to the alternating current, a pulse current or a pulsating current can be employed.

In addition, in the first embodiment, the vehicle engine mount using the vibrator having the structure according to the present invention has been described. However, the vibrator according to the present invention may be a vehicle body mount or a vehicle mount. It goes without saying that any of them can be applied to a differential mount or various vibration damping devices other than automobiles.

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.

[0062]

As is apparent from the above description, in the vibration isolator for a vibration isolator having the structure according to the present invention, only one of the shaft member and the housing cylinder member, which are relatively displaced, is provided. Since both the permanent magnet member and the coil member are assembled, the member on the side where the permanent magnet member and the coil member are mounted is used as a fixed member, and the other member is used as an output member that can be vibrated and displaced. Prevention of repeated deformation of the power supply lead wire to the coil member,
Weight reduction of the output member can be achieved at the same time, and excellent durability and improvement of output control accuracy up to a high frequency range can be advantageously realized.

Further, in the active vibration isolator having the structure according to the present invention, not only high performance is realized by excellent durability and control accuracy of the vibrator, but also in the initial state under the mounted state. Even when a load is input, the pressure increase of the fluid chamber is reduced or avoided by the pressure absorbing action of the equilibrium chamber, so that the intended vibration damping effect can be stably obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an active vibration isolator as one embodiment of the present invention.

FIG. 2 is an operation state explanatory view for explaining an operation of a vibration exciter in the active vibration isolator shown in FIG. 1;

FIG. 3 is another operation state explanatory view for explaining the operation of the vibrator in the active vibration isolator shown in FIG. 1;

FIG. 4 is a diagram illustrating still another operation state for explaining the operation of the vibrator in the active vibration isolator shown in FIG. 1;

FIG. 5 is an explanatory longitudinal sectional view showing a vibration exciter for a vibration isolator as one embodiment of the present invention, which can be employed in the active vibration isolator shown in FIG. 1;

FIG. 6 is an explanatory longitudinal sectional view showing a vibration exciter for a vibration isolator as another embodiment of the present invention.

FIG. 7 is an explanatory longitudinal sectional view showing a vibration exciter for a vibration isolator as still another embodiment of the present invention.

FIG. 8 is an explanatory longitudinal sectional view showing a vibration isolator for a vibration isolator as still another embodiment of the present invention.

[Explanation of symbols]

 10 Engine Mount 12 First Mounting Bracket 14 Second Mounting Bracket 16 Main Rubber Elastic Body 28 Equilibrium Chamber 56 Vibration Member 58 Connecting Rubber 68 Main Liquid Chamber 70 Sub Liquid Chamber 72 Vibrator 78 Shaft Bolt 80 Housing Cylindrical Fitting 82 , 83 permanent magnet 84, 85 coil 86 magnetic body 96 magnet / coil unit 100, 102, 104 yoke 108 lead wire 112 leaf spring

Claims (7)

[Claims] 1. A shaft member, a housing cylinder member spaced apart outward in a direction perpendicular to the axis of the shaft member and displaceable relative to the shaft member in the axial direction, and magnetic poles on both sides in the axial direction. In a state where the magnetic poles are set in the axial direction so that the polarities of the magnetic poles are opposite to each other, at least one pair of the shaft member and the housing tubular member fixedly arranged on one side of the housing member. A permanent magnet member, and a pair of magnetic fields formed by the pair of permanent magnet members, which are fixedly disposed with respect to the pair of permanent magnet members and form a unidirectional magnetic field by energization. While increasing the strength of
On the other hand, a coil member to be reduced, and fixedly disposed on either the other side of the shaft member and the housing cylinder member, are positioned in a magnetic field formed by the pair of permanent magnets, And a ferromagnetic member to which an axial driving force is exerted by changing the strength of a magnetic field formed by each pair of permanent magnets relatively by energizing the coil member. Exciter for equipment. 2. A guide mechanism between the shaft member and the housing cylinder member, which allows relative displacement of the two members in the axial direction while preventing relative displacement between the two members in the direction perpendicular to the axis. The vibrator for a vibration isolator according to claim 1, further comprising: 3. The vibrator according to claim 1, further comprising stopper means for limiting an axial relative displacement between the shaft member and the housing cylinder member. 4. The pair of permanent magnet members, respectively,
The inner peripheral surface of the permanent magnet member is fixed to the housing cylindrical member in an annular shape extending in the circumferential direction, and both magnetic poles of the permanent magnet members are set apart from each other in the axial direction on the inner peripheral surface of each permanent magnet member. Along with forming the coil member by disposing a coil between the two magnetic poles in the axial direction of each of the permanent magnet members, a cylindrical portion is provided for the ferromagnetic member, and the cylindrical portion is formed. It was arranged coaxially with each permanent magnet member, and the outer peripheral surface of the cylindrical portion was opposed to the inner peripheral surface where the magnetic pole was set in each permanent magnet member with a gap in the radial direction. A vibration exciter for a vibration isolator according to claim 1. 5. The vibration isolator according to claim 4, wherein the length of the ferromagnetic member in the axial direction is smaller than the entire length of the pair of permanent magnet members arranged in the axial direction in the axial direction. Shaker. 6. An axial driving force applied to the ferromagnetic member is increased in cooperation with the fact that the strength of the magnetic field by the pair of permanent magnets is relatively changed by energizing the coil member. The vibrator according to claim 1, wherein an auxiliary magnet is fixed to the ferromagnetic member. 7. A part of a wall portion is formed of a main rubber elastic body elastically deformed by input vibration to form a fluid chamber in which an incompressible fluid is sealed, and a separate wall portion of the fluid chamber is formed. 7. An active vibration isolator, wherein a part of the fluid vibration chamber is constituted by a displaceable vibration member, and the internal pressure of the fluid chamber can be controlled by vibrating the vibration member. And a relative displacement force in an axial direction generated between the shaft member and the housing cylindrical member in the vibration isolator for vibration isolator. While a part of the wall portion is formed of a flexible film which is easily deformed to form an equilibrium chamber in which an incompressible fluid is sealed, and the equilibrium chamber is formed by the fluid. An active vibration isolator, wherein a fluid communication passage communicating with the chamber is provided.