JPH10311367A - Active vibration damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a decrease in vibration damping performance, damage of a member, etc., due to a gall (contact) with a magnetic pole surface by a coil and a permanent magnet, in an active vibration damper having an electromagnetic exciting means constituted by including the coil and the permanent magnet. SOLUTION: Each one of a coil 22 and a permanent magnet 18 is supported to be mounted in each one of a shaft member 12 and an outer cylinder member 14 arranged separately mutually in the diametric direction, so that based on current carrying in the coil 22, electromagnetic force generated between the coil and the permanent magnet 18 is given so as to be influenced as relative displacement force in the axial direction between these shaft member 12 and outer cylinder member 14, also these shaft member 12 and outer cylinder member 14 are connected by a pair of elastic connection members 16, 16 in both end parts in the axial direction wherein the coil 22 and the permanent magnet 18 are interposed in the axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damper mounted on a vibration damping object to reduce vibration, and more particularly to an electromagnetic vibration means including a coil and a permanent magnet, and power supply to a coil member. The present invention relates to an active vibration damper that actively suppresses vibration by applying a vibration force based on an electromagnetic force generated by the vibration to a vibration damping target.

[0002]

2. Description of the Related Art Conventionally, as a means for reducing the vibration of a vibration damping target such as an automobile body which is a member in which vibration (including noise caused by vibration) is a problem, there has been a conventional method. JP-A-6-235438 and JP-A-7-17-1
As described in Japanese Patent Application Laid-Open No. 90139 and the like, a vibration force generating means is provided, and a vibration force corresponding to the vibration to be damped is applied to the vibration damping target, so that the vibration of the vibration damping target is actively activated. A vibration damper that can be reduced has been proposed. In addition, in such a vibration damper, a vibrating force generating means that can easily control the frequency, amplitude, phase, etc. of the vibrating force is desirable in order to obtain an effective vibration damping effect. An electromagnetic vibrating means in which a coil is disposed so as to be relatively displaceable therein and an exciting force is obtained based on an electromagnetic force generated between the coil and a permanent magnet by energizing the coil is preferably used. Has been adopted. And, with such electromagnetic vibration means,
Since the coil and the permanent magnet are relatively displaced in the axial direction of the coil, when attaching the damper to the damping target,
The axial direction of the coil substantially coincides with the vibration direction of the vibration damping target to be damped.

[0003] In such an electromagnetic vibrating means, it is desirable to dispose the coil sufficiently close to the magnetic pole surface of the permanent magnet in order to efficiently obtain a large vibrating force. However, in the conventional vibration damper, since the coil and the permanent magnet are generally elastically connected in a substantially cantilever structure, when an external force (vibration) in a direction perpendicular to the axis of the coil is applied, the coil and the permanent magnet are connected. The permanent magnet is easily displaced in the twisting direction (the direction in which the coil and the permanent magnet are inclined relative to the axial line of the coil), and the displacement in the twisting direction causes the coil to move toward the magnetic pole surface of the magnet. Contact may cause galling or the like, which may cause a serious problem such as disconnection of the coil or damage to components. Therefore, conventionally, as described in the above-mentioned publication, a sliding guide member for guiding the coil in the axial direction with respect to the permanent magnet is suitably adopted, and the coil and the permanent magnet are arranged in a direction perpendicular to the axis. Relative displacement is prevented.

However, if a sliding type guide member is provided for restricting the displacement of the coil and the permanent magnet in the direction perpendicular to the axis, a sliding resistance is generated when the coil and the permanent magnet are displaced in the axial direction, and the sliding resistance is large. However, the transmission efficiency of the excitation force to the vibration damping object is reduced, and the stability is not stable because the external force in the direction perpendicular to the axis exerted between the coil and the permanent magnet changes. there were.
For this reason, it was difficult to apply a sufficient excitation force that can exert an effective vibration damping effect to the vibration damping target, and there was a problem that the vibration damping effect was greatly reduced. is there.

[0005] In addition, there is a possibility that noise and other problems may occur due to abnormal noise (sliding contact noise) generated in the sliding portion of the guide member.

[0006]

Here, the inventions according to claims 1 to 4 have all been made on the background of the above-mentioned circumstances, and the problem to be solved is to solve the problem of the electromagnetic vibration means. In an active vibration damper provided with a coil, the displacement in the twisting direction of the coil and the permanent magnet is effectively suppressed without providing a sliding type guide member, so that the coil when an external force in the direction perpendicular to the axis is applied. It is an object of the present invention to provide an active damper having a novel structure capable of stably ensuring excellent transmission efficiency of an exciting force while preventing galling between the magnetic pole face and a magnetic pole surface caused by a permanent magnet.

[0007]

In order to solve such a problem, the feature of the invention according to claim 1 is as follows.
(A) a shaft member, (b) an outer cylindrical member spaced apart outward in a direction perpendicular to the axis of the shaft member, and (c) between an opposing surface of the shaft member and the outer cylindrical member in a direction perpendicular to the axis. (D) a permanent magnet disposed and supported on one of the shaft member and the outer cylinder member and supported between the shaft member and the outer cylinder member; The electromagnetic force generated between the permanent magnet by energization by being attached to and supported by one of the shaft member and the outer cylinder member,
(E) a coil that exerts an axial relative displacement force on the shaft member and the outer cylinder member; and (e) the shaft member on both axial sides of the permanent magnet and the coil that are located in the axial direction. An active vibration damper having a pair of elastic connecting members interposed between opposed surfaces of the outer cylindrical member in a direction perpendicular to the axis and elastically connecting the shaft member and the outer cylindrical member so as to be relatively displaceable in the axial direction. is there.

In the active vibration damper having the structure according to the first aspect of the present invention, one of the shaft member and the outer cylindrical member is attached to the vibration damping target and mounted. Either the shaft member or the outer cylinder member is elastically supported by the vibration damping object via a pair of elastic connecting members to form a single vibration system. By applying an exciting force based on the tightened electromagnetic force to the vibration system, an exciting force is applied to the vibration damping object via the vibration action of the vibration system.

Here, the shaft member or the outer cylindrical member constituting the vibration system is elastically supported by a pair of elastic connecting members interposed on both sides in the axial direction. When applied, displacement in the twisting direction is extremely effectively prevented, and a large spring stiffness is advantageously exhibited against the displacement in the twisting direction.Therefore, the coil can be provided without providing a special guide member or the like. The occurrence of inconvenience due to galling between the magnet and the magnetic pole surface can be effectively suppressed.

Further, since there is no need to provide a sliding type guide member, even when a load perpendicular to the axis is applied, the relative displacement characteristics of the coil and the permanent magnet in the axial direction and, consequently, the vibration damping target. Therefore, the transmission efficiency of the excitation force with respect to the vibration can be stably ensured, whereby the improvement and stabilization of the vibration damping effect can be effectively achieved.

The pair of elastic connecting members may be any as long as they elastically connect the shaft member and the outer cylindrical member while permitting relative displacement in the axial direction. An elastic body or a leaf spring made of metal or synthetic resin, which substantially expands in the radial direction, is employed. In other words, if such an elastic body is adopted, while ensuring a low dynamic spring characteristic with respect to the axial displacement of the shaft member and the outer cylindrical member, a high dynamic spring characteristic with respect to the displacement in the direction perpendicular to the axis is ensured. Also, the contact between the coil and the magnetic pole surface when a load is input in the direction perpendicular to the axis is advantageously prevented, and the vibration damping effect can be more stably achieved.

Further, as the pair of elastic connecting members, those having substantially the same elastic characteristics as described in claim 2 are preferably employed, whereby the structure is improved. And the displacement of the coil and the permanent magnet in the twisting direction when a load is input in the direction perpendicular to the axis can be more advantageously achieved.

[0013] More preferably, the apparatus includes a shaft member or an outer cylindrical member elastically supported by a pair of elastic connecting members with respect to an object to be damped, and a coil or a permanent magnet attached thereto. The center of gravity of the mass member in the vibration system to be set is set so as to be located substantially on the elastic main shaft in the direction perpendicular to the axis of the pair of elastic connecting members, whereby the coil and the The displacement of the magnet in the twisting direction can be more effectively prevented.

Further, the specific configuration of the electromagnetic driving means that generates a relative excitation force in the axial direction by including the coil and the permanent magnet is not limited at all. The configuration described in claim 3 can be suitably adopted. That is, a feature of the invention according to claim 3 is that, in the active vibration damper having a structure according to the invention according to claim 1 or 2, the permanent magnet includes the shaft member and the outer cylinder member. A closed magnetic path including the permanent magnet and the shaft member or the outer cylindrical member to which the permanent magnet is attached is formed in a ring shape extending in the circumferential direction and magnetic poles are set on both sides in the axial direction. On the closed magnetic path, a magnetic gap having magnetic pole surfaces opposed in the direction perpendicular to the axis is formed continuously in the circumferential direction,
The coil is arranged in such a magnetic gap. In the driving means having such a configuration, in the limited annular space between the shaft member and the outer cylinder member, the arrangement space of the coil can be efficiently secured, and
Since it is possible to obtain a large magnetic flux density in the space where the coil is provided, it is possible to efficiently obtain the exciting force on the vibration damping target with a compact structure.

Whether the coil or the permanent magnet is attached to the shaft member or the outer cylinder member, and which of the shaft member and the outer cylinder member is attached to the vibration damping object depends on the vibration to be damped. It is appropriately determined according to, for example, as described in claim 4, while attaching the permanent magnet to the shaft member, the shaft member,
By attaching to the vibration damping target, a configuration in which the outer cylinder member is elastically supported by the vibration damping target via the pair of elastic connecting members can be selectively and advantageously employed. That is, if such a configuration is adopted, the mass of the mass in the vibration system can be advantageously secured.
This makes it possible to exert a large excitation force on the object to be damped by using the resonance action of the vibration system more effectively.

[0016]

DETAILED 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.

First, FIG. 1 shows a vibration damper 10 according to one embodiment of the present invention. This vibration damper 10
An inner cylinder fitting 12 as a shaft member and an outer cylinder fitting 14 as an outer cylinder member, which are coaxially arranged at a predetermined distance in the radial direction, are axially moved by rubber elastic bodies 16 and 16 as elastic connecting members. The permanent magnet 18 is fixedly attached to the outer cylinder 14 while the coil 2 is fixed to the inner cylinder 12.
2 is fixedly mounted, and an electromagnetic force acts between the coil 22 and the permanent magnet 18 when the coil 22 is energized, so that the coil 22 and the permanent magnet 18, and furthermore, the inner cylindrical fitting 12 and the outer cylindrical fitting 14. Between them, an axial relative displacement force is generated. The vibration damper 10 is mounted by fixedly attaching the inner cylinder fitting 12 to a vibration control target (not shown), and a vibration force caused by a relative displacement between the inner cylinder fitting 12 and the outer cylinder fitting 14. Is applied to the object to be damped, whereby the vibration in the object to be damped is actively suppressed. In the following description, the vertical direction refers to the vertical direction in FIG.

More specifically, the inner cylindrical member 12 has a small-diameter, thick-walled cylindrical shape, and the upper and lower ends in the axial direction are each approximately の 長 in length and are located outside the central portion. The fitting tube 26 has a small diameter. Thereby, two step surfaces 27 are formed on the outer peripheral surface at the axially intermediate portion of the inner cylindrical fitting 12. On the other hand, the outer tube fitting 14 is
It has a large-diameter cylindrical shape, and the upper and lower ends in the axial direction are fitting tubes 28 each having a length of about 1/6 and an inner diameter larger than the central part. Further, the central portion of the outer tube fitting 14 has a lower end portion in the axial direction having a length of approximately 1/4 and an inner diameter dimension that is large enough not to reach the fitting tube portion 28 to form a press-fitting tube portion 29. I have. Thereby,
Three step surfaces 31 are formed on the inner peripheral surface at the axially intermediate portion of the outer cylinder fitting 12. The outer tube fitting 14 is provided so as to cover the outer peripheral surface of the inner tube fitting 12 radially outward at a predetermined distance, and the inner and outer tube fittings 1 are provided.
2 and 14 are elastically connected by a pair of rubber elastic bodies 16 at both ends in the upper and lower directions in the axial direction.

Each rubber elastic body 16 has a thick, substantially annular plate shape, and a fitting inner cylinder 30 is fitted on its inner peripheral surface, and a fitting outer cylinder 32 is fitted on its outer peripheral surface. Have been. Then, the fitting inner cylinder 30 is externally fitted and fixed to the fitting cylinder portion 26 of the inner cylinder fitting 12, is positioned in contact with the step surface 27, and the fitting outer cylinder 32 is fitted with the outer cylinder fitting 14. The inner cylindrical fitting 12 and the outer cylindrical fitting 14 are provided so as to be straddled between the inner cylindrical fitting 12 and the outer cylindrical fitting 14 by being internally fitted and fixed to the mounting cylinder portion 28 and positioned in contact with the step surface 31. Thereby, the inner cylinder fitting 12 and the outer cylinder fitting 1
4 is elastically connected in a state where relative displacement in the axial direction is allowed based on the elastic deformation of the rubber elastic bodies 16 and 16 and between the radially opposed surfaces of the inner and outer cylindrical fittings 12 and 14. Defines an annular internal space 33 whose both sides in the axial direction are substantially closed by rubber elastic bodies 16 and 16.

A bobbin 34 is attached to the inner cylindrical member 12 at an axially intermediate portion thereof. The bobbin 34 includes a large-diameter cylindrical wall 36 and the cylindrical wall 3.
6 has a substantially inverted cup shape as a whole with a bottom wall 38 covering the upper opening. A mounting hole 40 is formed in the center of the bottom wall portion 38, while the coil 22 is wound and fixed on the outer peripheral surface of the central portion of the cylindrical wall portion 36. After the mounting of the coil 22, a cylindrical cover member 43 is externally mounted on the cylindrical wall portion 36 of the bobbin 34, and the outer peripheral surface of the coil 22 is protected. In addition, as the material of the bobbin 34, besides the synthetic resin, a metal material, particularly a non-magnetic metal material such as an aluminum alloy can be used. However, when a conductive material is used, the eddy current is suppressed. Therefore, it is desirable to provide a slit 44 extending in the axial direction at one location on the circumference of the cylindrical wall portion 36.

The bobbin 34 is provided with a mounting hole 40.
In the figure, the inner peripheral edge of the bottom wall portion 38 is engaged with the stepped surface 27 of the inner cylinder fitting 12 while being externally inserted from the upper end in the axial direction of the inner cylinder fitting 12. By being pressed onto the surface 27, it is fixedly and coaxially attached to the inner cylinder fitting 12. Thereby, the bobbin 34 is accommodated and arranged in the internal space 33 defined between the inner and outer cylindrical fittings 12 and 14, and the wound cylindrical wall portion 36 of the coil 22 approaches the outer cylindrical fitting 14. It is located along the inner peripheral surface of the outer tube fitting 14. The power supply lead wire 48 for the coil 22 is drawn out to the outside through an axial through hole 50 formed in the fitting inner cylinder 30 at one axial end of the inner cylinder fitting 12.

On the other hand, a lower yoke 52 having a thick annular plate shape is inserted into the outer cylinder fitting 14 from below in the axial direction and is press-fitted and fixed to the press-fitting cylinder portion 29, and a step at the center in the axial direction. It is fixedly attached by being positioned in contact with the surface 31. As a result, the lower yoke 52 is positioned at a predetermined distance below the bobbin 34 in the internal space 33, and is disposed so as to protrude radially inward from the outer cylinder 14 toward the inner cylinder 12. ing. The inner diameter of the lower yoke 52 is larger than the outer diameter of the inner cylinder 12, and the lower yoke 52 is disposed in the inner cylinder 12 without being buffered.

On the lower yoke 52, the permanent magnet 18 and the upper yoke 56 each having an annular block shape are overlapped on the same axis in the axial direction, and the connecting bolt 58
Are integrally connected and fixed to each other. As a result, the upper and lower yokes 56 and 52 and the permanent magnet 18 are fixedly attached to the outer tube fitting 14 and positioned in the internal space 33. Each of the permanent magnet 18 and the upper yoke 56 has an inner diameter that is larger than the outer diameter of the inner cylindrical fitting 12 and an outer diameter that is smaller than the inner diameter of the cylindrical wall portion 36 of the bobbin 34. , Inner cylinder fitting 12 and bobbin 3
4 are inserted upward from the axially lower side between the radially opposed surfaces, and are disposed in the inner cylindrical fitting 12 and the bobbin 34 without being buffered.

Here, the permanent magnet 18 has both magnetic poles set on both sides in the axial direction (for example, as shown, an N pole is located on the upper side in the axial direction and an S pole is located on the lower side in the axial direction). Further, the outer tube fitting 14 and the upper and lower yokes 56 and 52 are
It is made of a ferromagnetic material such as iron.
The upper and lower yokes 56 and 52 are connected to the permanent magnet 18 to form a magnet member 62 that forms a magnetic path. That is, in the longitudinal section shown in FIG. 1, annular closed magnetic paths are formed on both sides of the inner cylinder fitting 12 by the magnet member 62, respectively. And the outer tube fitting 14 and the upper yoke 56
A magnetic gap 60 is formed between the radially opposite surfaces of the magnetic head. Then, with respect to the magnetic gap 60, the bobbin 3
4 is inserted and arranged, so that the bobbin 3
The coil 22 attached to the fourth 4 is disposed in the magnetic gap 60.

Accordingly, the vibration damper 1 having such a structure is provided.
At 0, when the coil 22 is energized, an electromagnetic force in the axial direction (vertical direction in FIG. 1) is generated between the coil 22 and the magnet member 62 due to the magnetic field existing in the magnetic gap 60. When an alternating current or a pulsating current is applied to the coil 22, a relative displacement force in the axial direction acts between the coil 22 and the magnet member 62 by the electromagnetic force, and the coil 22 and the magnet member 62 are separated from each other by a rubber elastic body. Based on the elastic deformation of No. 16, it is relatively displaced in the axial direction. In short, in this embodiment, the electromagnetic vibrating means is constituted by the coil 22 and the magnet member 62.

Therefore, the inner cylinder fitting 12 is fixedly attached to the vibration damping target by a bolt or the like inserted into the inner cylinder fitting 12, so that the axial direction of the inner and outer cylinder fittings 12 and 14 is adjusted in the vibration damping target. The vibration damper 10 is mounted on a vibration damping object so that the vibration direction substantially matches the vibration direction to be vibration-proofed, and under such a mounted state, the current supplied to the coil 22 is adjusted so that the vibration is prevented. By supplying a current having a frequency, a phase, and an amplitude corresponding to the vibration to the coil 22, the axial direction relative to the inner cylinder fitting 12 including the coil 22 and the outer cylinder fitting 14 including the magnet member 62 is determined. Based on the typical reciprocal displacement (vibration displacement), an exciting force for actively reducing the vibration to be damped can be exerted on the vibration damping target.

In particular, since the outer metal fitting 14 displaced by the electromagnetic force is resiliently supported by the rubber elastic members 16 and 16 to form one vibration system, the outer metal fitting 14 has a resonance function of the vibration system. Based on this, an efficient vibration transmission can be realized based on the above. By appropriately tuning the natural frequency of such a vibration system, it is possible to obtain an extremely effective vibration damping effect on the vibration in the specific frequency band in question. You can.

Further, the vibration damper 1 structured as described above
0, the inner tube fitting 12 supporting the coil 22;
An outer tube fitting 14 supporting a permanent magnet 18 is inserted and disposed inside and outside, and both axial portions thereof are elastically connected by rubber elastic bodies 16, respectively. Since it is connected to the metal fitting 12 by a both-end supporting structure supported on both sides in the axial direction, even when the radial vibration load is applied alone or simultaneously with the axial load as an external force, the outer cylindrical metal fitting 14 The displacement in the twisting direction with respect to the inner cylinder fitting 12 is advantageously suppressed.
In addition, the coil 22 and the permanent magnet 18
Since each of them is disposed at a substantially central portion between the pair of rubber elastic bodies 16 in the axial direction, the displacement in the twisting direction between the inner and outer cylinders 12 and 14 (the displacement of the inner and outer cylinders 12 and 14). Displacement in the direction where both central axes are relatively inclined)
In the case where the coil 22 and the permanent magnet 18 are provided, the amount of displacement due to the twisting is sufficiently reduced even when the occurrence of the wobbling occurs.

Therefore, in the vibration damper 10, even when a radial vibration load is applied as an external force between the inner and outer cylindrical fittings 12, 14, the coils 22 which are radially opposed to each other with a small gap therebetween. Galling between the magnetic pole surface (the inner facing surface of the magnetic gap 60) and the magnetic pole surface by the permanent magnet 18 is effectively prevented, and a smooth relative displacement in the axial direction can be stably exhibited. A vibration effect can be exerted.

Also, as described above, the pair of rubber elastic bodies 16,
16 and the inner and outer cylindrical fittings 12, 1
4, since the displacement in the twisting direction is suppressed, there is no need to provide a sliding type guide member as in the prior art. Therefore, in addition to the structure being extremely simple and excellent durability being exhibited, Problems such as a reduction in vibration damping effect and instability caused by sliding resistance and variations thereof, which have conventionally been problems, can be advantageously solved.

In particular, in the vibration damper 10 of the present embodiment, the pair of rubber elastic bodies 16 have the same structure as each other, and therefore have the advantage of simple structure and easy manufacture. In addition, the displacement of the inner and outer tube fittings 12 and 14 in the twisting direction when a radial vibration load is input can be more effectively suppressed.

In addition, in the vibration damper 10 of the present embodiment, the outer cylindrical metal fitting 1 which is relatively displaced with respect to the vibration damping target.
On the fourth side, the center of the mass including the permanent magnet 18 and the upper and lower yokes 56 and 52 is set at a substantially central portion in the axial direction of the outer tube fitting 14, and the radial direction of the pair of rubber elastic bodies 16 and 16 as a whole is set. The elastic main shaft of both rubber elastic bodies 1
6 and 16 have the same structure, so that the outer cylinder 1
4 is set at the center in the axial direction, the inclination displacement of the outer cylindrical member 14 when a radial vibration load is input is also advantageously prevented, and the magnetic pole surface formed by the coil 22 and the permanent magnet 18 Contact such as galling with the like is more effectively prevented.

Next, FIG. 2 shows a vibration damper 70 as a second embodiment of the present invention. The vibration damper 70 is another specific example of a pair of elastic connecting members for elastically connecting a shaft member and an outer cylindrical member to the vibration damper 10 according to the first embodiment. Therefore, for members and portions having the same structure as the first embodiment,
The same reference numerals as in the first embodiment denote the same in the drawings, and a detailed description thereof will be omitted.

That is, in the vibration damper 70 of the present embodiment, two cylindrical upper and lower positioning sleeves 72 and 73 are externally inserted into the axially central portion of the inner cylindrical fitting 12, and the axially end surfaces thereof are formed. They are positioned in contact with each other. Then, after the bobbin 34 and the thin leaf-shaped upper leaf spring 74 are externally inserted from outside in the axial direction of the upper positioning sleeve 72, the upper pressing sleeve 76 having a thin cylindrical shape is formed.
Are externally fitted and fixed to the inner tube fitting 12, whereby
The inner peripheral edges of the bobbin 34 and the upper leaf spring 74 are clamped between the axially opposing surfaces of the upper positioning sleeve 72 and the upper pressing sleeve 76 and are fixed to the inner cylinder fitting 12. Note that an annular wiring sleeve 78 having a through hole 50 for taking out the power supply lead wire 48 to the coil 22 to the outside is fixed to the upper holding sleeve 76.

Further, from outside of the lower positioning sleeve 73 in the axial direction, after a thick ring-shaped spacer 80 and a thin annular plate-shaped lower leaf spring 82 are externally inserted into the inner cylindrical fitting 12,
A lower holding sleeve 84 having a thin cylindrical shape is externally fitted and fixed to the inner cylinder fitting 12.
The inner peripheral edge portion 2 is sandwiched between the axially opposed surfaces of the lower positioning sleeve 73 and the lower pressing sleeve 84 via the spacer 80, and is fixed to the inner cylinder fitting 12.

The upper and lower positioning sleeves 72, 73
Are provided with cushioning rubber 85 protruding on the outer peripheral surface at the axially outer end. When the inner and outer tube fittings 12 and 14 are relatively displaced in the axial direction, the bobbin 34 and the upper yoke 56 or the spacer 80 and the lower yoke 52 are buffered in the axial direction via the buffer rubber 85. The inner and outer cylinder fittings 12,
14, the relative displacement amount is limited.

On the other hand, a thick-cylindrical outer yoke 86 and a thin-cylindrical yoke fixing sleeve 88 are press-fitted and fixed to the outer cylinder fitting 14 on both sides in the axial direction with the lower yoke 52 interposed therebetween. The outer yoke 86 and the yoke fixing sleeve 88 pinch the outer peripheral edge of the lower yoke 52 in the axial direction, and the lower yoke 52 is fixed to the outer tube fitting 14. Here, the outer yoke 86 is
The magnet member 62 is formed of a ferromagnetic material and forms a closed magnetic path in cooperation with the upper and lower yokes 56 and 52 and the permanent magnet 18. The coil 22 is disposed between the inner peripheral surface of the outer yoke 86 and the outer peripheral surface of the upper yoke 56.
Are formed to form a magnetic gap 60.

The outer peripheral edge of the upper leaf spring 74 is superposed on the axially outer end face of the outer peripheral yoke 86. Further, the upper leaf spring 74 has an annular upper side. A press ring 90 is press-fitted into the inner tube fitting 12 and is fixedly disposed. As a result, the outer peripheral edge of the upper leaf spring 74 is clamped between the axially opposing surfaces of the outer yoke 86 and the upper pressing ring 90, and is fixed to the outer tube fitting 14.

Further, the outer peripheral edge of the lower leaf spring 82 is overlapped on the axially outer end face of the yoke fixing sleeve 88, and further, on the axially outer side of the lower leaf spring 82,
A lower press ring 92 having an annular shape is press-fitted into the inner cylinder fitting 12 and is fixedly disposed. As a result, the outer peripheral edge of the lower leaf spring 82 is clamped between the axially opposing surfaces of the yoke fixing sleeve 88 and the lower pressing ring 92 and is fixed to the outer tube fitting 14.

In short, in the vibration damper 70 having the above-described structure, a pair of elastic members for connecting the inner and outer cylinders 12 and 14 are provided between the axially opposite ends of the inner and outer cylinders 12 and 14, respectively. , Are constituted by upper and lower leaf springs 74 and 82 which are interposed in the radial direction.
Based on the elastic deformation of the upper and lower leaf springs 74 and 82, relative displacement of the inner and outer cylindrical fittings 12 and 14 in the axial direction is allowed. The upper and lower leaf springs 74 and 82 may be any as long as they allow the relative axial displacement of the inner and outer cylindrical fittings 12 and 14 based on their elastic deformation. Can also be adopted.

In such a vibration damper 70 as well, the outer cylinder 14 to be vibrated includes the upper and lower leaf springs 74 and 82.
As a result, the inner cylinder 1 of the outer cylinder 14 is supported similarly to the vibration damper in the first embodiment.
2 is advantageously suppressed in the torsion direction, and galling between the coil 22 and the pole face by the permanent magnet 18 is effectively prevented, thereby improving and stabilizing the vibration damping effect against axial vibration. The same effects as those of the vibration damper in the first embodiment, such as the above, can be similarly exhibited.

In particular, if the leaf springs 74 and 82 are employed, it is easy to set the spring rigidity in the direction perpendicular to the axis to be large, and the relative displacement of the inner and outer cylindrical fittings 12 and 14 in the radial direction is advantageously suppressed. There is also an advantage of gaining. Furthermore, the adoption of the metal leaf springs 74 and 82 has an effect that the heat resistance of the vibration damper can be advantageously secured.

Next, FIG. 3 shows a vibration damper 100 as a third embodiment of the present invention. The vibration damper 100 has, as a shaft member, a mass rod 102 having a solid rod shape having a circular cross section. In addition, an outer cylinder fitting 104 as an outer cylinder member having a large-diameter cylindrical shape is coaxially disposed so as to surround the mass rod 102 at a predetermined distance in the radial direction. The outer tube fitting 104 has a flange portion 106 that extends radially outward at an upper end portion in the axial direction. The mass rod 102 is desirably a non-magnetic material having an appropriate weight.
For example, an aluminum alloy is advantageously used.

A pair of rubber elastic bodies 108, 108 are interposed between the mass rod 102 and the outer cylindrical fitting 104 at both axial ends, and the rubber elastic bodies 108, 108 102 and the outer tube fitting 104 are elastically connected. The rubber elastic body 108 has a thick, substantially annular plate shape, and has a thin inner cylinder 1 on its inner peripheral surface and outer peripheral surface, each having a thin cylindrical shape.
10 and the fitting outer cylinder 112 are vulcanized and bonded. The fitting inner cylinder 110 is externally fitted and fixed to the axial end of the mass rod 102, and the fitting outer cylinder 112 is
4, the rubber elastic body 108 is interposed between the inner and outer cylindrical fittings 12 and 14 and is mounted thereon, and the inner cylindrical fitting 12 and the outer cylindrical fitting 14 are radially opposed to each other. A rubber elastic body 108 is interposed therebetween. Also, thereby, between the mass rod 102 and the outer cylinder fitting 104,
An annular internal space 114 that is continuous in the circumferential direction is defined between the pair of rubber elastic bodies 108.

Further, the mass rod 102 has a permanent magnet 11 having a thick annular plate shape at an axially intermediate portion.
Upper and lower yokes 116 and 118 each having a thick annular plate shape are superposed on both sides in the axial direction of No. 5, and a magnet member 120 closely contacted in a sandwich shape is externally inserted. The periphery is the mass rod 10
2 fitted inner cylinders 110, 1 externally fitted and fixed to both ends in the axial direction.
By being sandwiched between the members 10 in the axial direction, they are fixedly attached to the mass rod 102 as a whole. In this case, the magnetic poles of the permanent magnet 115 are set on both sides in the axial direction, so that in the magnet member 120, both magnetic poles are set in the upper yoke 116 and the lower yoke 118.

On the other hand, a coil member 122 is inserted and fixed to the outer tube fitting 104 at an axially intermediate portion. The coil member 122 has a structure in which a first coil 126 and a second coil 128 are wound around a bobbin 124 having a substantially cylindrical shape at a predetermined distance from each other in the axial direction. And such a coil member 12
2 is inserted into the outer tube fitting 104 and disposed along the inner peripheral surface of the outer tube fitting 104, and the outer peripheral edge thereof is press-fitted and fixed to both axial ends of the outer tube fitting 104. Fitting outer cylinder 1
It is fixedly attached to the outer tube fitting 104 by being sandwiched in the axial direction between the first and second tubes 112 and 112.

As a result, the magnet member 120 attached to the mass rod 102 and the coil member 122 attached to the outer cylinder fitting 104 are both made of a pair of rubber elastic bodies 1.
In the inner space 114 defined between 08 and 108, it is arranged in the central portion in the axial direction. Further, the first coil 126 of the coil member 122 is
0, and the second coil 128 of the coil member 122 is radially opposed to the lower yoke 118 of the magnet member 120. I have.
Thereby, both the first coil 126 and the second coil 128 are arranged in the magnetic field by the magnet member 120. If the outer metal fitting 104 is made of a ferromagnetic material, the magnet member 120 and the upper and lower yokes 116, 1
An annular magnetic path having a closed structure is formed by the outer ring member 18 and the outer cylindrical member 104, and the first and second coils 126 and 128 are disposed in the magnetic gap formed on the annular magnetic path. It is possible to obtain a strong electromagnetic force.

The vibration damper 100 having such a structure is as follows.
The outer cylindrical fitting 104 is press-fitted into a mounting hole provided in a predetermined vibration damping target, and is fixedly mounted by being positioned by the flange portion 106. Then, under such a mounted state, the first and second coils 12
When an alternating current or a pulsating current is applied to the coils 6 and 128, the coil 12
An electromagnetic force is generated between the magnet member 120 and the magnet member 120, and the electromagnetic force causes the magnet member 120, the coil member 122, and thus the mass rod 102 and the outer cylinder fitting 14, based on the elastic deformation of the rubber elastic body 108. , Are reciprocally displaced relatively in the axial direction. In short, in the present embodiment, the magnet member 120 and the coil member 122
This constitutes the electromagnetic vibration means.

Therefore, the outer cylinder fitting 104 is fixed to the vibration damping target such that the axial directions of the mass rod 102 and the outer cylinder fitting 104 substantially coincide with the vibration direction in which vibration is to be prevented in the vibration damping target. When the vibration damper 100 is mounted on the vibration damping target, the coils 126, 1
The current having a frequency, phase and amplitude corresponding to the vibration to be damped is adjusted by adjusting the supply current to the coil 28.
By supplying power to the magnet members 120 and
The mass rod 102 including the coil member 122 and the like is reciprocally displaced (vibrated) in the axial direction with respect to the outer cylinder fitting 104 including the coil member 122 and the like. Can be exerted to actively reduce the vibration.

Therefore, the vibration damper 100 of this embodiment is
In the same manner as in the vibration dampers of the first and second embodiments, the mass rod 102 and the rubber elastic bodies 108, 10
An effective vibration damping effect can be exerted on the vibration damping target through the vibration action of the vibration system configured including 8.

Moreover, in such a vibration damper 100,
Similarly to the vibration damper in the first embodiment, the mass rod 102 to be vibrated is supported by a pair of rubber elastic bodies 108, 108 in a double-supported structure with respect to an outer cylinder 104 fixed to the vibration damping target. Therefore, the displacement of the mass rod 102 in the twisting direction with respect to the outer cylinder fitting 104 is advantageously suppressed, and the galling between the coil member 122 and the magnet member 120 is effectively prevented, whereby the axial vibration is prevented. Any of the effects similar to those of the vibration damper in the first embodiment, such as improvement and stabilization of the vibration damping effect, can be effectively exerted.

The embodiments of the present invention have been described above in detail, but these are literal examples.
It should not be construed that the configuration of the embodiment is limited.

For example, the specific structure of the electromagnetic driving means is as follows.
It should not be construed as limiting in any way by the description of the above-described embodiment, and any conventionally known various structures that generate an exciting force by energizing a coil disposed in a magnetic field may be employed. It is, of course, possible. Specifically, for example, a permanent magnet is attached to one of the shaft member and the outer cylinder member that is fixedly attached to the vibration damping target, and the permanent magnet is attached to the vibration damping target via an elastic member. A coil may be attached to the other side of the vibration system.

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

[0055]

As is apparent from the above description, in the vibration damper having the structure according to the first to fourth aspects of the present invention, any of the shafts which are relatively displaced in the axial direction by energizing the coil. Since the member and the outer cylinder member are elastically connected at both ends in the axial direction by a pair of elastic connecting members disposed so as to sandwich the electromagnetic driving means including the coil and the permanent magnet in the axial direction. Even when a load in the direction perpendicular to the axis is applied between the shaft member and the outer cylinder member, the relative displacement in the twisting direction between the two members is extremely effectively prevented, and the magnetic pole surfaces of the coil and the magnet are prevented. The occurrence of inconvenience due to galling or the like is effectively avoided, and the improvement and stabilization of the vibration damping performance can be advantageously achieved.

[Brief description of the drawings]

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

FIG. 2 is an explanatory longitudinal sectional view showing a vibration damper as a second embodiment of the present invention.

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

[Explanation of symbols]

 10, 70, 100 Damper 12 Inner tube 14 Outer tube 16 Rubber elastic body 18 Permanent magnet 22 Coil 62 Magnet member 74 Upper leaf spring 82 Lower leaf spring 102 Mass rod 104 Outer cylinder fitting 108 Rubber elastic body 115 Permanent magnet 120 Magnet member 122 Coil member 126 First coil 128 Second coil

Claims (4)

[Claims] A shaft member; an outer cylinder member spaced apart outward in a direction perpendicular to the axis of the shaft member; and an outer cylinder member disposed between opposing surfaces of the shaft member and the outer cylinder member in a direction perpendicular to the axis. A permanent magnet attached to and supported by one of the shaft member and the outer cylinder member; and a permanent magnet disposed between the shaft member and the outer cylinder member in a direction perpendicular to the axis thereof. By being attached to and supported by one of the other members, an electromagnetic force generated between the permanent magnet by energization is exerted as an axial relative displacement force on the shaft member and the outer cylinder member. On both sides in the axial direction of the coil, the permanent magnet and the coil are both sandwiched in the axial direction, interposed between the shaft member and the facing surface of the outer cylindrical member in a direction perpendicular to the axis, and A pair of elastic connections for elastically connecting the cylindrical members so that they can be relatively displaced in the axial direction An active vibration damper comprising: a member; 2. The active vibration damper according to claim 1, wherein said pair of elastic connecting members have substantially the same elastic characteristics. 3. The permanent magnet has a ring shape extending in the circumferential direction between the shaft member and the outer cylindrical member, and has magnetic poles on both sides in the axial direction. A closed magnetic path is configured including the attached shaft member or the outer cylindrical member, and a magnetic gap having a magnetic pole surface opposed in a direction perpendicular to the axis on the closed magnetic path is formed continuously in a circumferential direction. And the coil is disposed in the magnetic gap.
4. The active vibration damper according to claim 1. 4. The permanent magnet is attached to the shaft member, and the shaft member is attached to a vibration damping target. The active vibration damper according to claim 1, wherein the active vibration damper is elastically supported via the pair of elastic connection members.