JP2012141027A - Vibration isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration isolator that prevents damping characteristics and spring characteristics for vibration from being changed even when a load is changed and the deterioration of vibration isolating performance is reduced, with a simple constitution.SOLUTION: The vibration isolator 10 includes: a fixed plate which is horizontally fixed and arranged; a movable plate which is arranged on the upper part of the fixed plate and is supported to be relatively moved with respect to the fixed plate via at least three elastic members disposed between the fixed plate and the movable plate; and damper parts arranged adjacent to the elastic members between the fixed plate and the movable plate. Each damper part is constituted of a reception member which is fixed to the fixed plate or the movable plate, a disk-shaped damper material made of viscoelastic body which is arranged coaxially to be slidable in the reception member and a support shaft whose one end is connected to the neighborhood of the center of the damper material, and the other end of the support shaft is supported so as to be swung via a swinging means with respect to the movable plate or the fixed plate.

Description

  The present invention elastically supports various precision devices, such as a microscope and a balance, which are easily affected by vibrations, with respect to a work table or the like, and suppresses vibrations of the work table or the like from propagating to the precision devices. The present invention relates to a vibration isolator.

Conventionally, as such a vibration isolation device, for example, Patent Document 1 discloses a vibration isolation device (anti-vibration support device) that combines an elastic body and a viscoelastic body, and is configured as shown in FIG. ing.
That is, in FIG. 13, the vibration isolator 1 includes a coil spring 2 as an elastic body, a damper material 3 as a viscoelastic body, and a pair of flanges 4 to which both ends of the coil spring 2 and the damper material 3 are attached. It is configured.

The damper material 3 is formed in a cylindrical shape with, for example, an epoxy resin.
Then, both ends of the damper material 3 and both ends of the coil spring 2 are attached to the flanges 4 in a state where the damper material 3 is inserted into the hollow portion of the coil spring 2.
At that time, in a state where the elastic center in the load direction acting on the composite of the coil spring 2 and the damper material 3 is encased on the viscoelastic body, that is, the damper material 3 side, both ends of the coil spring 2 and the damper material 3 correspond to the flanges 4 respectively. It is being fixed with the screw 5 with respect to.

According to the vibration isolator 1 having such a configuration, one side, for example, the lower flange 5 is attached to the fixed plate, and the other side, for example, the upper flange 5 is attached to the movable plate, and the fixed plate is placed on the upper surface of the work table or the like. At the same time, a precision device to be isolated is mounted on the movable plate. Thereby, a large attenuation can be obtained on the movable plate with respect to vibrations acting in the horizontal direction (lateral direction) and the vertical direction (vertical direction) with respect to the fixed plate.
Here, the load acting on the coil spring 2 is calculated based on the weight and the center of gravity of the precision device to be isolated, and the spring constant is selected so that the amount of deflection of the coil spring 2 becomes a reference value. That is, the spring constant of the coil spring 2 and the damping characteristic of the damper material 3 are set exclusively for the precision instrument.
As a result, it is possible to manufacture a vibration isolator having the optimal vibration isolation performance for the precision instrument.

  JP 63-30628 A

By the way, the vibration isolator 1 described above cannot be used for various precision instruments because the spring constant of the coil spring 2 and the damping characteristic of the damper material 3 are set exclusively for the precision instrument.
Therefore, when the vibration isolator 1 is used to perform vibration isolation of precision equipment having various weights, the amount of deflection of the coil spring 2 is not constant depending on the weight of the precision equipment.

なる式１で表される。
この式から、除振装置の固有振動数ｆ_０は、精密機器の質量Ｍに依存し、精密機器が重くなると、固有振動数ｆ_０が低くなり、また精密機器が軽くなると、固有振動数ｆ_０が高くなることが分かる。
同様に、ダンパー材３のバネ定数ｋｄが大きくなると、固有振動数ｆ_０は高くなり、バネ定数ｋｄが小さくなると、固有振動数ｆ_０は低くなる。In general, the natural frequency f ₀ of the vibration isolator is such that the spring constant of the coil spring 2 is ks, the spring constant of the damper material 3 is kd, the mass of the precision device is M, and the movable part mass of the vibration isolator is m.

It is represented by the following formula 1.
From this equation, the natural frequency f ₀ of the vibration isolator depends on the mass M of the precision device. When the precision device becomes heavy, the natural frequency f ₀ decreases, and when the precision device becomes light, the natural frequency f 0. It turns out that ₀ becomes high.
Similarly, when the spring constant kd of the damper material 3 is increased, the natural frequency f ₀ is higher, the spring constant kd is reduced, natural frequency f ₀ is lowered.

Here, in the case where precision instruments having various weights are mounted on the movable plate, the amount of crushing of the damper material 3 is not constant in the cylindrical damper material 3 described above. For this reason, not only the desired damping characteristic cannot be obtained, but also the spring characteristic of the damper material 3 varies greatly. Accordingly, as the weight of the precision instrument to be mounted changes, the natural frequency f _{0 of the} vibration isolation device 1 also changes greatly, and the vibration isolation performance deteriorates.

  In view of the above points, the present invention provides a vibration isolator having a simple configuration that suppresses changes in damping characteristics and spring characteristics with respect to vibration and reduces deterioration in vibration isolation performance even when the load changes. The purpose is to provide.

  According to the present invention, the above object is achieved through the fixing plate horizontally fixed and the at least three elastic members disposed above the fixing plate and interposed between the fixing plate and the fixing plate. Each of the damper parts is composed of a movable plate that is supported so as to be movable relative to the fixed plate, and a damper portion that is disposed adjacent to each elastic member between the fixed plate and the movable plate. Are each a receiving member fixed to the fixed plate or the movable plate, a disk-shaped damper material coaxially and slidably disposed in the receiving member, and a center of the damper material A support shaft having one end connected in the vicinity thereof, and the other end of the support shaft is supported to be swingable with respect to the movable plate or the fixed plate via a swinging means. This is achieved by the featured vibration isolation device.

  In the vibration isolator according to the present invention, preferably, the receiving member and the support shaft in each damper portion are arranged perpendicular to the fixed plate and the movable plate in a no-load state.

  In the vibration isolator according to the present invention, preferably, the receiving member, the damper material, and the support shaft in each of the damper portions are disposed so as to be inclined toward the center from one of the fixed plate and the movable plate to the other in an unloaded state. Has been.

  In the vibration isolator according to the present invention, preferably, the receiving member has a cylindrical inner wall surface.

  In the vibration isolator according to the present invention, it is preferable that the receiving member has a tapered truncated cone-shaped inner wall surface from the opening side toward the fixed side.

  In the vibration isolator according to the present invention, preferably, the swinging means is constituted by a coil spring mounted on a peripheral surface at the other end of the support shaft.

  In the vibration isolator according to the present invention, preferably, the swinging means is made of a cylindrical rubber material mounted on a peripheral surface at the other end of the support shaft.

  The vibration isolator according to the present invention is preferably constituted by a linear spring in which the swinging means is connected to the support shaft.

  The vibration isolator according to the present invention is preferably configured such that the swinging means is a rubber plate provided perpendicular to the support shaft in a no-load state on the surface of the support region of the movable plate or the fixed plate. ing.

According to the above configuration, when precision devices with various masses are mounted on the movable plate, the elastic member generates a deflection amount in the vertical direction according to a load acting downward on the movable plate.
Here, since the damper material of the damper portion is slidable in the receiving member, the damper material moves along the axial direction in the receiving member by the amount of bending described above.
Therefore, the contact state between the damper member and the receiving member in the damper portion is constant regardless of the amount of bending of the elastic member. As a result, the change in the spring characteristics and damping characteristics of the damper material due to the weight of the precision equipment mounted on the movable plate is extremely small, so that the mass of the precision equipment mounted affects the vibration isolation characteristics of the vibration isolation device. There is nothing.

In addition, when an operator operates a precision device mounted on the movable plate of the vibration isolator, the support shaft of the damper portion is fixed when the movable plate is displaced in the horizontal direction relative to the fixed plate. And the damper material is inclined with respect to the receiving member. At this time, since the damper material is greatly deformed, the damping characteristic is increased. Thereby, the free vibration of the movable plate of the vibration isolator and the precision instrument is quickly suppressed.
Furthermore, since the horizontal spring constant in the damper portion can be reduced, the natural frequency in the horizontal direction of the vibration isolation device can be set low, and the vibration isolation performance of the vibration isolation device is improved.

  When the receiving member has a tapered truncated cone-shaped inner wall surface from the opening side toward the fixed side, the mass of the precision instrument mounted on the movable plate is heavy, and the amount of bending of the elastic member is large. When the damper material is pushed deeper into the hollow portion of the receiving member, the amount of deformation of the damper material increases and the spring characteristics of the damper material become stronger. Therefore, the combined spring constant of the elastic member and the damper material is increased, the influence of the mass of the precision instrument is offset, and the decrease in the natural frequency of the vibration isolator is suppressed.

Also, if the precision instrument is light and the elastic member has a small amount of deflection, the damper material is located closer to the opening in the hollow portion of the receiving member, so that the amount of deformation of the damper material is small, or the damper material Does not contact the inner wall surface of the receiving member, so that the spring constant of the damper material is weakened. Therefore, the combined spring constant of the elastic member and the damper material is reduced, and an increase in the natural frequency of the vibration isolation device is suppressed.
In this way, since the change in the natural frequency of the vibration isolator due to the mass of the precision instrument mounted on the movable plate is reduced, sufficient vibration isolation characteristics can be obtained regardless of the weight of the precision instrument to be isolated. Is obtained.

  Thus, according to the vibration isolator according to the present invention, even if the load changes, changes in the damping characteristic and the spring characteristic with respect to vibration can be suppressed, and deterioration of the vibration isolation performance can be reduced.

  It is a schematic side view which shows the structure in the use condition of 1st embodiment of the vibration isolator by this invention.   It is a disassembled perspective view of the vibration isolator of FIG.   It is an expanded sectional view which shows the structure of the damper part in the vibration isolator of FIG.   FIG. 2 is a partially cutaway side view showing an enlarged swinging means for a support shaft of a damper portion in the vibration isolator of FIG. 1.   FIG. 2 is a schematic side view showing a state in which a horizontal displacement has occurred in a precision instrument in the vibration isolation device of FIG. 1.   It is a schematic side view which shows the state which mounted the precision instrument lighter than the precision instrument in the vibration isolator of FIG.   It is a schematic side view which shows the state which mounted the precision instrument heavier than the precision instrument in the vibration isolator of FIG.   It is an expanded sectional view which shows the structure of the damper part in 2nd embodiment of the vibration isolator by this invention.   FIG. 9 is an enlarged cross-sectional view illustrating a state where (A) a heavy precision device is mounted and (B) a light precision device is mounted in the damper portion of FIG. 8.   It is an expanded sectional view which shows the structure of the damper part in 3rd embodiment of the vibration isolator by this invention.   It is an expanded sectional view which shows the structure of the damper part in 4th embodiment of the vibration isolator by this invention.   It is an expanded sectional view which shows the structure of the damper part in 5th embodiment of the vibration isolator by this invention.   It is a schematic side view which shows the structure of an example of the conventional vibration isolator.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 12.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

1 and 2 show the configuration of the first embodiment of the vibration isolator according to the present invention.
1 and 2, a vibration isolator 10 includes a fixed plate 11, a movable plate 12, a plurality of coil springs 13 and dampers as elastic members disposed between the fixed plate 11 and the movable plate 12. Part 20.

The fixed plate 11 is composed of, for example, a plate-like member such as metal that is horizontally fixed on the work table 14.
More specifically, in the illustrated case, the fixing plate 11 is placed on the work table 14 via rubber feet 11a provided on the bottom surfaces of the four corners.

Similarly, the movable plate 12 is made of a plate-like member such as metal, and is disposed horizontally above the fixed plate 11 at a predetermined interval.
Further, the movable plate 12 supports a precision device 15 such as a microscope or a balance placed on the upper surface thereof.
Here, the precision instrument 15 is arranged on the movable plate 12 so that the center of gravity thereof is located on the vertical axis V passing through the center of the movable plate 12 in the horizontal direction (X direction and Y direction in FIG. 2).

As shown in FIG. 2, the coil springs 13 are arranged in the vicinity of the four corners of the fixed plate 11 and the movable plate 12, respectively, so as to extend perpendicularly to the fixed plate 11 and the movable plate 12, that is, in the Z direction.
Each coil spring 13 has a lower end 13 a fixed to the fixed plate 11 and an upper end 13 b fixed to the movable plate 12.
Here, each coil spring 13 receives a load due to the weight of the precision device 15 and the movable plate 12 placed on the movable plate 12, and is elastically deformed by an amount of deflection determined by its spring constant.

  Each damper portion 20 is disposed adjacent to the corresponding coil spring 13. In the illustrated case, each damper portion 20 is disposed closer to the center in the X direction than the corresponding coil spring 13, that is, closer to the vertical axis V.

  Each damper part 20 is comprised from the receiving member 21, the damper material 22, and the spindle 23 as shown in detail in FIG.

  In this case, the receiving member 21 is formed in a hollow cylindrical shape by, for example, an aluminum material, and the upper end is fixed to the lower surface of the movable plate 12 by a screw 21a.

The damper material 22 is formed of two viscoelastic bodies formed in a thin disk shape, for example, low-elasticity rubber, and is attached to the support shaft 23 at a predetermined interval by a spacer 22a.
Here, the outer diameter of the damper material 22 is selected to be slightly larger than the inner diameter of the cylindrical hollow portion of the receiving member 21, and is always compressed against the inner wall in the hollow portion of the receiving member 21. Abutting and slidable along the longitudinal direction of the receiving member 21.

The support shaft 23 is made of, for example, a rod-shaped member such as metal, and the lower end thereof is supported so as to be swingable with respect to the upper surface of the fixed plate 11 via the swinging means 24.
In this case, the oscillating means 24 includes a fixing member 24b fixed by a screw 24a provided on the fixing plate 11, a screw portion 24c, and a spring member 24d.
The screw portion 24c is a stud bolt, and is fixed and held on the upper surface of the fixing member 24b by welding or the like, and extends vertically upward from the upper surface of the fixing member 24b and the fixing plate 11.

As shown in FIG. 4, the spring member 24 d is formed by winding a diamond-shaped stainless steel wire rod into a coil shape, and the pitch is formed at the screw pitch of the screw portion 24 c and the lower end of the support shaft 23 described later. The screw pitch of the formed screw portion 23a is set to be the same, and the inner diameter thereof is set to be substantially the same as the inner diameters of the screw portion 24c and the screw portion 23a.
Thereby, the lower end of the spring member 24d is externally inserted into the screw portion 24c.

On the other hand, the upper end of the spring member 24d is extrapolated to the screw portion 23a provided at the lower end of the support shaft 23 described above. At that time, in a state where the support shaft 23 and the screw portion 24c are abutted in the vertical direction so that the distance between the lower end surface of the support shaft 23 and the upper end surface of the screw portion 24c is about 1 mm inside the spring member 24d. And held by the spring member 24d.
Accordingly, since the spring member 24d can be expanded and contracted in the region of the above-described interval, the support shaft 23 is located at the lower end thereof with respect to the screw portion 24c via the spring member 24d, that is, on the upper surface of the fixing plate 11. On the other hand, it is supported to be swingable.

The vibration isolator 10 according to the embodiment of the present invention is configured as described above. For example, when the precision device 15 is mounted, as illustrated in FIG. 1, the load due to the weight of the precision device 15 and the movable plate 12 is The movable plate 12 is applied to each coil spring 13 and supports the movable plate 12 in a floating state in a state where each coil spring 13 is bent by elastic deformation by this load.
Accordingly, in each damper portion 20, the damper portion 22 slides in the vertical direction within the hollow portion of the receiving member 21 in response to the reduction due to the elastic deformation of each coil spring 13, and stops at the illustrated height position H <b> 1. .

In such a state, as shown in FIG. 5, for example, when the precision device 15 is operated, the operator applies a force to the precision device 15 in the horizontal direction. When the displacement is caused by vibration or the like in the direction of arrow A, the central axis of each coil spring 13 is inclined by an angle θ as shown in the figure.
At this time, the receiving member 21 of the damper portion 20 is also displaced in the direction of arrow A by the same amount as the movable plate 12, but the support shaft 23 is supported by the swinging means 24 so as to be swingable with respect to the fixed plate 11. As the support shaft 23 is tilted by swinging, the damper material 22 is greatly bent. Due to this bending deformation, the amount of energy absorbed by the damper material 22 increases, so that the convergence of free vibration in the horizontal direction in the vibration isolation device 10 is promoted.
Since the spring constant in the swinging direction of the swinging means 24, that is, the spring member 24b when the support shaft 23 swings is small, the horizontal natural frequency in the vibration isolator 10 is the horizontal direction of the coil spring 13. Determined by the spring constant.

Next, a case where a precision instrument 15L that is lighter than the precision instrument 15 described above is mounted on the movable plate 12 will be described.
In FIG. 6, a load due to the weight of the precision device 15 </ b> L and the movable plate 12 is applied to each coil spring 13, and the movable plate 12 is supported in a floating state in a state where each coil spring 13 is bent due to elastic deformation by this load. .
In this case, since the weight of the precision device 15L is lighter than the weight of the precision device 15, the load applied to each coil spring 13 is reduced by the weight difference. Therefore, as shown in FIG. 6, the amount of bending of each coil spring 13 is reduced.

Accordingly, in each damper portion 20, the damper portion 22 slides in the vertical direction within the hollow portion of the receiving member 21 in response to the reduction due to the elastic deformation of each coil spring 13, and the receiving member 21 is shown in FIG. It rests at a height position H2 higher than the height position H1.
That is, in each damper portion 20, the damper material 22 is located near the lower end of the receiving member 21.
At this time, since the damper material 22 only moves in the axial direction within the cylindrical receiving member 21, the contact state of the outer peripheral edge of the damper material 22 with the inner surface of the receiving member 21 is substantially the same. Therefore, even if the precision instrument 15 is changed to a lighter precision instrument 15L, the damping characteristics and spring characteristics of the damper material 22 hardly change.

A case where a precision device 15H heavier than the above-described precision device 15 is mounted on the movable plate 12 will be described.
In FIG. 7, a load due to the weight of the precision device 15H and the movable plate 12 is applied to each coil spring 13, and the load is used to support the movable plate 12 in a floating state in a state where each coil spring 13 is bent due to elastic deformation. .
In this case, the amount of deflection of each coil spring 13 is such that the weight of the precision device 15H is heavier than the weight of the precision device 15, so the load applied to each coil spring 13 increases by the weight difference. Therefore, as shown in FIG. 7, the amount of deflection of each coil spring 13 increases.

Accordingly, in each damper portion 20, the damper material 22 slides in the vertical direction within the hollow portion of the receiving member 21 in response to compression by the elastic deformation of each coil spring 13, and the receiving member 21 is shown in FIG. It stops at a height position H3 lower than the height position H1.
That is, in each damper portion 20, the damper material 22 is positioned near the upper end of the receiving member 21.

  In this way, even if precision instruments 15, 15L or 15H having different weights are mounted on the movable plate 12, the damper material 22 only moves in the axial direction within the cylindrical receiving member 21. The contact state of the outer peripheral edge of the damper material 22 with the inner surface of the receiving member 21 is substantially the same. Therefore, even if the precision instrument 15 is changed to a lighter precision instrument 15L or a heavier precision instrument 15H, the damping characteristics and spring characteristics of the damper material 22 hardly change.

  Thus, according to the vibration isolator 10 according to the embodiment of the present invention, even if the weight of the precision device 15 mounted on the movable plate 12 changes, the contact state of the damper material 22 hardly changes, that is, The damping characteristic and the spring characteristic of the damper material 22 are hardly changed, and the deterioration of the vibration isolation characteristic can be suppressed.

FIG. 8 shows the configuration of the damper portion in the second embodiment of the vibration isolator according to the present invention.
In FIG. 8, the vibration isolator has substantially the same configuration as that of the vibration isolator 10 shown in FIGS. 1 and 2, and the same components are denoted by the same reference numerals and description thereof is omitted.
This vibration isolator differs from the vibration isolator 10 shown in FIGS. 1 and 2 only in the configuration of the damper portion 20.

  In other words, in FIG. 8, in this vibration isolator, the damper portion 30 includes a receiving member 31, a damper material 22, and a support shaft 23.

The receiving member 31 has an inner wall surface formed in a tapered truncated cone shape upward, and its upper end is fixed to the lower surface of the movable plate 12 by a screw 31a.
Here, the frustoconical hollow portion of the receiving member 31 has an inner diameter at the lower end larger than the outer diameter of the damper material 22, an inner diameter at the upper end smaller than the outer diameter of the damper material 22, and an axial direction of the hollow portion ( The inner diameter at a height position of a quarter from the lower side (vertical direction) is formed to be the same as the outer diameter of the damper material 22.

  According to the vibration isolator having such a configuration, the same effect as that of the vibration isolator 10 shown in FIG. 1 is obtained, and when the heavy precision device 15H is mounted on the movable plate 12, FIG. As shown in FIG. 3, the amount of bending of each coil spring 13 increases, and in each damper portion 30, the damper material 22 slides in the vertical direction within the hollow portion of the receiving member 31 in response to compression due to elastic deformation of each coil spring 13. By moving, the receiving member 31 moves downward from the height position shown in FIG.

At this time, since the inner diameter of the inner wall surface of the receiving member 31 is gradually reduced, the outer periphery of the damper member 22 is compressed inward and deformed into an umbrella shape as shown in FIG. As a result, the damping characteristics of the damper material 22 increase, the spring characteristics also change, and the spring constant increases.
Therefore, the amount of energy absorbed by the damper material 22 when the heavy precision instrument 15H freely vibrates increases, and the attenuation increases. Thereby, convergence of the free vibration of the heavy precision instrument 15H is promoted.

  Furthermore, the composite spring constant by the coil spring 13 and the damper material 22 also increases. Since the natural frequency of the vibration isolator 10 is determined based on the ratio of the spring constant and the mass based on the above-described formula 1, when the heavy precision device 15H is mounted, the change in the ratio decreases as the spring constant increases. The change in the natural frequency of the vibration isolator is also reduced.

  On the other hand, when the light precision device 15L is mounted on the movable plate 12, the amount of bending of each coil spring 13 is reduced as shown in FIG. Corresponding to the extension due to the elastic deformation of the coil spring 13, the damper member 22 slides in the vertical direction in the hollow portion of the receiving member 31, and the receiving member 31 moves upward from the height position shown in FIG.

At this time, since the inner diameter of the inner wall surface of the receiving member 31 of the damper member 22 gradually increases, the pressing force on the outer periphery decreases, and the lower damper member 22 has its outer periphery separated from the inner wall surface of the receiving member 31. To do. As a result, the damping characteristic of the damper material 22 is reduced, the spring characteristic is also changed, and the spring constant is reduced.
Accordingly, the amount of energy absorbed by the damper material 22 when the light precision instrument 15L freely vibrates is reduced, and the attenuation is reduced. Thereby, the convergence of the free vibration of the light precision instrument 15L is prevented from being overdamped.
Furthermore, since the composite spring constant by the coil spring 13 and the damper material 22 is also reduced, the change in the natural frequency of the vibration isolator is also reduced.

FIG. 10 shows the configuration of the damper portion in the third embodiment of the vibration isolator according to the present invention.
10, this vibration isolator has substantially the same configuration as that of the vibration isolator 10 shown in FIGS. 1 and 2, and therefore, the same components are denoted by the same reference numerals and description thereof is omitted.
This vibration isolator differs from the vibration isolator 10 shown in FIGS. 1 and 2 only in the configuration of the damper portion 20.

That is, in FIG. 10, in this vibration isolator, the swinging means 24 in the damper portion 20 includes a hollow cylindrical connecting member 24e made of, for example, a rubber tube member, instead of the coil spring-like spring member 24d. Yes.
Further, on the fixing member 24a, a cylindrical portion 24f is provided instead of the screw portion 24c.
Then, circumferential grooves 24g and 23b are formed on the outer peripheral surface at the upper end of the cylindrical portion 24f and the outer peripheral surface at the lower end of the support shaft 23.

Here, the inner diameter of the connecting member 24e is selected to be smaller than the outer diameters of the cylindrical portion 24f and the support shaft 23.
Thereby, when the upper end and lower end of the connecting member 24e are fitted on the lower end of the support shaft 23 and the upper end of the columnar portion 24f, the connecting member 24e bites into the circumferential grooves 24g, 23b, thereby connecting the connecting member 24e. The falling off of the support shaft 23 and the cylindrical portion 24f of 24e is prevented.
At that time, since the interval between the lower end surface of the support shaft 23 and the upper end surface of the cylindrical portion 24f is about 1 mm in the connecting member 24e, the connecting member 24e can be expanded and contracted in the region of this interval. The shaft 23 is supported at its lower end via a connecting member 24e, that is, swingable with respect to the fixed plate 11.

  According to the vibration isolator having such a configuration, it operates in the same manner as the vibration isolator 10 shown in FIGS. 1 and 2.

FIG. 11 shows the configuration of the damper portion in the fourth embodiment of the vibration isolator according to the present invention.
In FIG. 11, the vibration isolator has substantially the same configuration as the damper portion in the vibration isolator illustrated in FIG. 10, and thus the same components are denoted by the same reference numerals and description thereof is omitted.
This vibration isolator differs from the vibration isolator shown in FIG. 10 only in the configuration of the damper portion 20.

That is, in FIG. 11, in this vibration isolator, the swinging means 24 in the damper portion 20 includes a wire spring 24h instead of the connecting member 24e made of a rubber tube member.
Holes 24i and 23c are provided at the centers of the upper end surface of the cylindrical portion 24f on the fixing member 24a and the lower end surface of the support shaft 23, respectively.

Thereby, the upper end and the lower end of the wire spring 24h are press-fitted into the hole 23c on the lower end surface of the support shaft 23 and the hole 24i on the upper end surface of the columnar portion 24f, and the line spring 24h is inserted into the support shaft 23 and the columnar portion 24f. Fixed concentrically.
At that time, since the distance between the lower end surface of the support shaft 23 and the upper end surface of the cylindrical portion 24f is about 1 mm, the wire spring 24h can be elastically deformed in the region of this interval. The lower end is supported so as to be swingable with respect to the fixed plate 11 via a wire spring 24h.

  According to the vibration isolator having such a configuration, it operates in the same manner as the vibration isolator 10 shown in FIGS. 1 and 2.

FIG. 12 shows the configuration of the damper portion in the fifth embodiment of the vibration isolator according to the present invention.
In FIG. 12, the vibration isolator has substantially the same configuration as the vibration isolator shown in FIGS. 1 and 2, and therefore, the same components are denoted by the same reference numerals and description thereof is omitted.
This vibration isolator differs from the vibration isolator 10 shown in FIGS. 1 and 2 only in the configuration of the damper portion 20.

That is, in FIG. 12, in this vibration isolation device, the damper portion 40 includes a swinging means 41 instead of the swinging means 24.
The swinging means 41 includes a flat hollow cylindrical fixing member 42, a disk-like elastic member 43 attached to the upper end of the fixing member 42, a flange 44 attached to the upper surface at the center of the elastic member 43, It is composed of

The fixing member 42 is made of, for example, a metal pipe or the like, and is fixed on the fixing plate 11.
The elastic member 43 is made of, for example, a rubber plate, and the outer peripheral edge thereof is fixed to the upper end outer periphery of the fixing member 42.
The flange 44 is integrally attached to the lower end of the support shaft 23 and is coaxially fixed to the upper surface of the elastic member 43 at the center.

As a result, the lower end of the support shaft 23 is attached to the fixed plate 11 via the flange 44, the elastic member 43 and the fixed member 42.
At this time, the support shaft 23 is attached perpendicularly to the surface of the elastic member 43 and is supported so as to be swingable with respect to the fixed plate 11 by elastic deformation of the elastic member 43.

  According to the vibration isolator having such a configuration, it operates in the same manner as the vibration isolator 10 shown in FIGS. 1 and 2.

  In addition, the receiving member, the damper material, and the support shaft in the damper portion may be arranged so as to be inclined toward the central axis from one of the fixed plate and the movable plate to the other in an unloaded state.

In the vibration isolator 10 according to the above-described embodiment of the present invention, the movable plate 12 is supported by the four coil springs 13 disposed near the four corners with respect to the fixed plate 11, and is positioned adjacent to each coil spring 13. However, the present invention is not limited to this, and the movable plate 12 on which the precision device 15, 15L or 15H is mounted is supported in a balanced manner with respect to the fixed plate 11. If it is done, it is obvious that it may be supported by at least three or more coil springs 13 and damper portions 20.
At this time, the arrangement locations of the coil springs 13 and the damper portions 20 may be selected so that their weighted average positions are aligned in the vertical direction with the center of gravity of the precision device 15.

  In the above-described embodiment, each damper portion 20, 30, 40 is disposed adjacent to the corresponding coil spring 13 on the inner side in the X direction. However, the present invention is not limited to this, and each damper portion 20, 30, 40 may be arranged on the inner side in the Y direction with respect to the corresponding coil spring 13 or near the center of the fixed plate 11 and the movable plate 12.

  In the above-described embodiment, the coil spring 13 is used to support the movable plate 12 with respect to the fixed plate 11, but not limited to this, other types of elastic members may be used. it is obvious.

  Further, in the above-described embodiment, the case of performing vibration isolation of the precision instruments 15, 15L, and 15H has been described. However, it may be used for vibration isolation of other various apparatus devices, particularly precision instruments. Is clear.

  As described above, according to the present invention, even if the load changes, a very excellent vibration isolation device is provided in which the change in the damping characteristics and the spring characteristics against vibration is suppressed and the deterioration of the vibration isolation performance is reduced. Can be done.

10 vibration isolator 11 fixed plate 12 movable plate 13 coil spring (elastic member)
14 Work table 15 Precision instrument 15H Heavy precision instrument 15L Light precision instrument 20, 30, 40 Damper part 21, 31 Receiving member 22 Damper member 23 Support shaft 24, 41 Oscillating means 42 Fixing member 43 Elastic member 44 Flange

Claims (9)

It is movable relative to the fixed plate through at least three elastic members disposed between the fixed plate arranged horizontally and the fixed plate, and interposed between the fixed plate and the fixed plate. A movable plate supported by the damper plate, and a damper portion disposed adjacent to each elastic member between the fixed plate and the movable plate, and
Each of the damper portions is a receiving member fixed to the fixed plate or the movable plate, a disk-shaped damper material made of a viscoelastic body coaxially and slidably disposed in the receiving member, It consists of a support shaft with one end connected near the center of the damper material,
The other end of the support shaft is supported so as to be swingable with respect to the movable plate or the fixed plate via a swinging means.
A vibration isolator characterized by that.   2. The vibration isolation device according to claim 1, wherein the receiving member and the support shaft in each of the damper portions are arranged perpendicular to the fixed plate and the movable plate in an unloaded state.   The receiving member, the damper material, and the support shaft in each of the damper portions are arranged so as to be inclined toward the center side from one of the fixed plate and the movable plate to the other in an unloaded state. Item 6. The vibration isolator according to item 1.   The vibration isolator according to any one of claims 1 to 3, wherein the receiving member has a cylindrical inner wall surface.   The vibration isolator according to any one of claims 1 to 3, wherein the receiving member has a tapered truncated cone-shaped inner wall surface from the opening side toward the fixed side.   The vibration isolator according to any one of claims 1 to 5, wherein the swinging means is constituted by a coil spring mounted on a peripheral surface at the other end of the support shaft.   The vibration isolator according to any one of claims 1 to 5, wherein the swinging means is formed of a cylindrical rubber material attached to a peripheral surface at the other end of the support shaft.   The vibration isolator according to any one of claims 1 to 5, wherein the swinging means is constituted by a linear spring connected to the support shaft.   2. The swinging means is composed of a rubber plate provided perpendicularly to the support shaft in an unloaded state on the surface of a support region of the movable plate or the fixed plate. 6. The vibration isolator according to any one of 5 to 5.

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