JP2004324871A - Liquid sealed vibration damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid sealed vibration damper having a wider-range resonance frequency in a resonance orifice. <P>SOLUTION: A main liquid chamber 5 partially formed by an insulator 4 is communicated with a sub liquid chamber 8 via a damping orifice 7. An inner pressure absorbing film 17 is provided on a wall portion of the main liquid chamber 5 and its film tension is controlled by a film tension varying means 18. The film tension varying means 18 has a press member 20 and a solenoid 22 for moving it forward and backward. The press member 20 has a stepwise press face 25. When the press member 20 is pressed against the inner pressure absorbing film 17 by the solenoid 22, a pressure area is changed with a stroke and film tension is nonlinearly changed. As a result, an expansion spring is greatly changed to produce a great change in resonance frequency accordingly, providing a wider-range resonance frequency. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ring vibration isolator used for an engine mount of a vehicle, which has a resonance orifice and performs vibration isolation by resonance of a liquid column, and more particularly to a device capable of broadening a resonance frequency.
[0002]
[Prior art]
A first mounting member mounted on the vibration source side, a second mounting member mounted on the vibration receiving side, an insulator interposed therebetween for absorbing vibration, and a liquid in which the insulator forms part of a wall. And a liquid chamber partitioned into a main liquid chamber and a sub liquid chamber, which are communicated with each other through an orifice passage, and an internal pressure absorbing film is provided on a part of a wall surrounding the main liquid chamber. An internal pressure absorption type liquid ring engine mount in which the membrane tension is changed is known. In this type of engine mount, if the internal pressure absorbing film is softened, the internal pressure change is absorbed to make it a low dynamic spring, and if it is made rigid, the expansion spring, which is the spring constant generated by the internal pressure change of the engine mount, is raised. The flow rate to the orifice passage is increased, thereby increasing resonance efficiency and reducing vibration transmission.
[0003]
[Patent Document 1] JP-A-7-305740 [Patent Document 2] JP-A-2002-70930 [Patent Document 3] JP-A-2002-70931 [Patent Document 4] JP-A-2002-168284 [Patent] Reference 5: Japanese Patent Application Laid-Open No. 2002-250392 Patent Document 6: Japanese Patent Application Laid-Open No. 2003-4090
FIG. 12 is a diagram showing in principle the control of the internal pressure absorbing film in the conventional liquid ring engine mount, which controls the free deformation of the internal pressure absorbing film shown in A and changes the tension of the internal pressure absorbing film shown in B. Some change the expansion spring. That is, in A, a negative pressure chamber c is provided on the side opposite to the main liquid chamber b of the internal pressure absorbing film a, and when the pressure is made negative, the internal pressure absorbing film a is suction-fixed to the inner wall of the negative pressure chamber c to restrict free deformation. It is supposed to. In B, the drive member d directly attached to the internal pressure absorbing film a is moved from the neutral position (0) to the main liquid chamber b side (+ side) or the opposite side (− side) to move back and forth. The membrane tension is increased, and as a result, the expansion spring is increased. In the present application, the movement toward the main liquid chamber b is referred to as (+), and the opposite side is referred to as retreat (-).
[0005]
In the above AB, when the internal pressure absorbing film a is not controlled, the internal pressure absorbing film a is freely elastically deformed to absorb the internal pressure fluctuation and reduce the expansion spring due to the internal pressure generated by the vibration input to the main liquid chamber b. In this way, a low dynamic spring is obtained. However, with respect to the input from the suspension, which is a vibration having a low frequency (about 10 Hz) and a small amplitude during normal running, free vibration is regulated by adjusting the clearance to maintain the damping performance.
At the time of control, in the case of A, the internal pressure absorbing film a is fixed by the application of a negative pressure or the like and free vibration is regulated, so that the expansion spring is improved and the orifice resonance is improved in efficiency. In the case of B, the tension of the internal pressure absorbing film a is generated by moving the internal pressure absorbing film a in the + or − direction from the 0 position (when not controlled), thereby improving Kf and increasing the efficiency of the orifice resonance. .
[0006]
[Problems to be solved by the invention]
FIG. 13 shows a change in resonance when the change in tension of the internal pressure absorbing film in B is used. As shown in A, when the internal pressure absorbing film a is elastically deformed to x0 to x3, as shown in B, the expansion spring gradually increases, and the resonance frequency fn changes to fx1 to fx3. That is, between the resonance frequency change Δfx and the extension spring change ΔKf, Δfx∝ (ΔKf) ^1/2
There is a relationship.
B indicates the resonance frequency on the horizontal axis and the phase at the resonance frequency on the vertical axis.
[0007]
As is clear from this graph, the change in the resonance frequency when the membrane tension control is used is caused by the change in the extension spring (ΔKf), but the internal pressure absorbing film needs to maintain the damping performance when not controlled. Therefore, ΔKf cannot be changed extremely, and the control frequency band Δfx is in a very limited range. Therefore, if a phase of δ1 or more is required in the frequency band of f1 to f3 in the region from the idle state to the start, the control frequency band Δfx is only between f1 and f2 in the above figure, and in the section between f2 and f3, Since the phase is less than δ1, an effective cutoff effect cannot be obtained in this section. Therefore, it is desired to widen the control frequency band Δfx.
[0008]
For this purpose, it is conceivable to change the film tension change of the internal pressure absorbing film non-linearly with respect to the magnitude of the input vibration. FIG. 14A shows that the amount of elastic deformation of the internal pressure absorbing film 1 changes nonlinearly from the reference position x0 to xα and further to xβ. At this time, as shown in B, with respect to the deformation amount x on the horizontal axis, the film tension F on the vertical axis sharply rises from xα and shows a nonlinear change e. Assuming that a straight line between x0 and xα is g, the difference Δ between g on xβ and the non-linearized portion e is an increase of ΔKf. As a result, the control frequency band Δfx can be expanded. Therefore, if the film tension of the internal pressure absorbing film can be changed non-linearly, the control frequency band Δfx can be expanded. Therefore, the present invention aims to realize this.
[0009]
[Means for Solving the Problems]
The liquid seal vibration isolator according to claim 1, wherein a first mounting member mounted on the vibration source side, a second mounting member mounted on the vibration receiving side, and an insulator interposed therebetween for absorbing vibration. A liquid chamber forming a part of the wall, the liquid chamber is divided into a main liquid chamber and a sub liquid chamber, and the two liquid chambers communicate with each other via a resonance orifice. In a liquid-sealed vibration isolator provided with an internal pressure absorption film made of an elastic film that partially elastically deforms and absorbs changes in internal pressure,
It is provided with a pressing member that is pressed against the internal pressure absorbing film, and a film tension changing unit that continuously or multi-stagely changes the tension of the internal pressure absorbing film according to the amount of advance / retreat stroke of the pressing member. Features.
[0010]
A second aspect of the present invention is characterized in that, in the first aspect, the pressing surface shape of the pressing member changes stepwise.
[0011]
A third aspect of the present invention is characterized in that, in the first aspect, the cross-sectional shape of the internal pressure absorbing film changes irregularly.
[0012]
A fourth aspect of the present invention is characterized in that, in the third aspect, a deformation regulating stopper is provided on the internal pressure absorbing film to make the sectional shape irregular.
[0013]
A fifth aspect of the present invention is characterized in that, in the third aspect, a positioning portion is provided at a central portion of the internal pressure absorbing film to make the cross-sectional shape irregular.
[0014]
According to a sixth aspect of the present invention, in any one of the first to fourth aspects, the resonance orifice is an idle orifice and is used for controlling the resonance frequency.
[0015]
A seventh aspect of the present invention is characterized in that in any one of the first to fourth aspects, the resonance orifice is a damping orifice, which is used to eliminate the frequency dependence of the liquid column resonance.
[0016]
An eighth aspect of the present invention is characterized in that in any one of the first to seventh aspects, the driving means of the pressing member is a solenoid or an intake negative pressure.
[0017]
【The invention's effect】
According to the first aspect, when the internal pressure absorbing film is provided with a pressing member that is pressed against the internal pressure absorbing film, and the tension of the internal pressure absorbing film is changed continuously or in multiple steps by the amount of advance / retreat stroke of the pressing member, the internal pressure absorbing film is provided. The pressing area of the film changes continuously or in multiple steps. As a result, the film tension changes non-linearly and the expansion spring changes, so that the change in the resonance frequency can be widened and a high phase can be obtained. In addition, compared to the conventional active type liquid ring vibration isolator, the structure can be simplified and the cost can be reduced.
[0018]
According to the second aspect, since the pressing surface shape of the pressing member is changed stepwise, the pressing area can be easily changed depending on the stroke amount.
[0019]
According to the third aspect, by making the cross-sectional shape of the internal pressure absorbing film irregular, the film tension can be changed non-linearly with respect to the stroke amount of the pressing member.
[0020]
According to the fourth aspect, since the internal pressure absorbing film is provided with the deformation restricting stopper, as the elastic deformation of the internal pressure absorbing film increases, the tension of the deformation restricting stopper increases, making it difficult for the internal pressure absorbing film to elastically deform. , The expansion spring can be increased non-linearly.
[0021]
According to the fifth aspect, since the positioning portion is provided at the center portion of the internal pressure absorbing film, it is possible to prevent the displacement of the pressing member during the stroke.
[0022]
According to the sixth aspect, by controlling the film tension of the internal pressure absorbing film at the time of idling, the resonance frequency can be broadened, and a high phase can be obtained. Vector control becomes possible, and vibration on the vehicle body side can be effectively suppressed.
[0023]
According to the seventh aspect, when the change of the resonance frequency is controlled by controlling the film tension of the internal pressure absorbing film when the liquid column resonance occurs due to the damping orifice, the phase generated by the resonance can be made high, and therefore, the original phase can be obtained. Where the resonance frequency changes depending on the deformation amount and deformation speed of the liquid ring vibration isolator, the high frequency makes it possible to maintain the resonance frequency constant and eliminate the frequency dependency. it can.
[0024]
According to the eighth aspect, it is possible to easily drive the pressing member by setting the driving means of the pressing member to a solenoid or an intake negative pressure.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments will be described with reference to the drawings. 1 and 2 relate to a liquid ring engine mount common to the embodiments, FIG. 1 is a top view thereof, and FIG. 2 is a sectional view corresponding to line 2-2 in FIG. In the following description, “up and down” is based on the state in FIG.
[0026]
In FIG. 1, the liquid-tight engine mount 1 includes a first mounting member 2, a second mounting member 3, and an insulator 4. The first mounting member 2 is connected to a vibration source side such as an engine (not shown), and the second mounting member 3 is connected to a vibration receiving side such as a vehicle body (not shown).
[0027]
As shown in FIG. 2, the insulator 4 is a well-known rubber vibration isolator having a substantially conical shape made of rubber. However, a known elastic vibration isolating member having a substantially conical shape made of a suitable elastic material such as rubber and other elastomers can be used, and the first mounting member 2 and the second mounting member 3 are connected and integrated. I do.
[0028]
A main liquid chamber 5 is formed inside the first mounting member 2, the second mounting member 3, and the insulator 4, and a well-known incompressible working fluid is sealed therein. The main liquid chamber 5 communicates with the sub liquid chamber 8 via a damping orifice 7 formed on the outer periphery of the partition member 6. The damping orifice 7 absorbs, with high damping, vibration during normal running which affects the riding comfort of low frequency and small amplitude of about 10 Hz. The sub liquid chamber 8 is covered by a diaphragm 9.
[0029]
The partition member 6 is formed by vertically integrating a resin or metal upper member 10, a rubber middle member 11, and a resin or metal lower member 12, and each is a disk-shaped member. The material is not particularly limited. The damping orifice 7 is formed between the outer peripheral portions of these three members. 7b in the figure is an outlet.
[0030]
An idle orifice 13 is formed between the upper member 10 and the middle member 11. The idle orifice 13 communicates with the main liquid chamber 5 and the sub liquid chamber 8 to generate a liquid column resonance at an engine vibration frequency at the time of idling to reduce the dynamic spring. Vibration transmission to the mounting member 3 is cut off. The idle orifice 13 is openable and closable, the details of which will be described later.
[0031]
The peripheral wall of the main liquid chamber 5 is constituted by an upper cylindrical member 14 which is a part of the second mounting member 3 and a cylindrical elastic wall 15 which covers the inside thereof. The cylindrical elastic wall 15 is an extension formed continuously and integrally with the insulator 4. An opening 16 is formed in a part of the upper cylindrical member 14, and a portion of the cylindrical elastic wall 15 overlapping the opening 16 is an internal pressure absorbing film 17. The internal pressure absorbing film 17 is an elastic film made of an appropriate elastic material such as rubber, and has a spring capable of affecting the internal pressure of the main liquid chamber 5. In this embodiment, it is integral with the cylindrical elastic wall 15, but this part may be formed as a separate member and have different spring constants.
[0032]
Outside the internal pressure absorbing film 17, that is, on the opposite side of the main liquid chamber 5 across the internal pressure absorbing film 17, a film tension varying means 18 is provided, and is supported on the flange 19 at the lower end of the upper cylindrical member 14 or by another member. ing. The film tension varying means 18 includes a pressing member 20 pressed against the internal pressure absorbing film 17 and a solenoid 22 that allows an armature 21 integrated with the pressing member 20 to move in the axial direction. The armature 21 is made of a magnetic material, and advances and retreats with respect to the internal pressure absorbing film 17 depending on the direction of the line of magnetic force generated by the solenoid 22, and the stroke amount is proportional to the strength of the magnetic field generated by the solenoid 22.
[0033]
The control of the drive current for the solenoid 22 is performed by the control device 23, and is controlled based on the detection signal of the rotation sensor 24 that detects the engine speed. The sensor signal serving as the basis of the control is not limited to the rotational speed, but may be another appropriate sensor detection amount indicating the operation state of the engine or a sensor detection amount related to direct input vibration. The driving means is not limited to the solenoid 22, and various known means such as negative pressure of intake air of the engine can be used.
[0034]
The pressing surface 25 of the pressing member 20 pressed against the internal pressure absorbing film 17 changes stepwise. Although the details of this will be described later, since the pressing area of the internal pressure absorbing film 17 pressed by the pressing member 20 changes according to the stroke amount of the pressing member 20, the film tension of the internal pressure absorbing film 17 changes. . As a result, when the film tension of the internal pressure absorbing film 17 increases, the expansion spring, which is a spring generated by a change in the internal pressure as the vibration isolator, increases. The adjustment of the membrane tension of the internal pressure absorbing membrane 17 can be controlled either in multiple stages or continuously.
[0035]
The outlet 26 of the idle orifice 13 on the side of the auxiliary liquid chamber 8 is openable and closable by an opening / closing valve 27 formed at the center of the diaphragm 9, and is open only in an idle frequency range, and is closed in other cases. The opening / closing valve 27 is pressed against the head 31 of the elastic member 30 and is opened and closed by the expansion and contraction of the elastic member 30.
[0036]
A hollow negative pressure chamber 33 is formed between the head 31 and the bottom 32 of the elastic member 30. The negative pressure chamber 33 is configured to switch the connection between the intake negative pressure and the atmosphere via a ventilation nozzle 34. When the intake negative pressure is applied, the valve moves downward in the figure against the return spring 35, and the opening / closing valve 27 opens the outlet 26. When the intake negative pressure is shut off and the atmosphere is released, the return spring 35 And exit 26 is closed.
[0037]
Next, a first embodiment of the film tension control will be described with reference to FIGS. As shown in FIG. 3, the pressing surface 25 has a step-like shape, the tip (top) 25 a forms an initial clearance d0 between the pressing surface 25 and the internal pressure absorbing film 17, the next step 25 b has d1, and the next step 25 b has d1. The stage 25c changes to d2, and the bottom stage 25d forms d3. Then, when the pressing member 20 is pushed out by the solenoid 22, as shown in FIGS. 4A to 4C, the pressing area in which the internal pressure absorbing film 17 is pressed changes from S1 to S3 with the pressing displacement of d1 to d3.
[0038]
FIG. 5 is a graph showing the effect on the internal pressure absorbing film 17 due to the change in the stroke amount of the pressing member 20. As shown by a solid line in accordance with the change in the amount of pressing displacement of the pressing member 20, the holding area is As a result, the area of the internal pressure absorbing film 17 that can be freely elastically deformed decreases, and the film tension changes in a multi-step manner as a whole, as shown by a dotted line, which rises to the right. At this time, the inclination of the broken line portion of the film tension corresponding to each pushing displacement amount increases and changes in multiple stages from θ1 to θ3, and changes to θ1 <θ2 <θ3.
[0039]
When the membrane tension changes in multiple stages, the expansion spring increases in multiple stages in accordance with the membrane tension. Therefore, if the pushing displacement amount is controlled to d1 to d3, a non-linear Kf change can be obtained. That is, by making the film tension non-linear, ΔKf can be increased and Δfx can be increased.
[0040]
6 to 8 show a second embodiment. As shown in FIG. 6, in this embodiment, the pressing member 20 has a substantially shell shape, and the pressing surface 25 is continuous and substantially streamlined. When the pressing member 20 is continuously pushed out toward the internal pressure absorbing film 17, as shown in FIGS. 7A to 7C, the pressing portion 20 presses the internal pressure absorbing film 17 in the pressing member 20 in accordance with the pressing amount x. The area increases and changes. Therefore, the pressing area of the pressing member 20 is correspondingly increased.
[0041]
FIG. 8 is a graph corresponding to FIG. 5 and shows the effect on the internal pressure absorbing film 17 due to the change in the stroke amount of the pressing member 20, and the solid line according to the change in the pushing displacement amount of the pressing member 20. As shown by, the holding area increases in a straight line rising to the right, as a result, the area of the internal pressure collecting membrane 17 that can be freely elastically deformed decreases, and the membrane tension becomes a continuous curve rising as a whole as shown by the dotted line. It changes in shape. Therefore, the non-linear change is performed steplessly and continuously. Therefore, this can further simplify the structure.
[0042]
FIG. 9 shows the relationship between the change of the resonance frequency and the phase in the first and second embodiments, where fa and fb are the required reference phase δ1 frequencies, f1 is the resonance frequency in the free state, and f2 is only the film tension. Is the maximum controllable resonance frequency when f is changed, and f3 is the maximum controllable resonance frequency when the holding area is changed.
[0043]
As is clear from this figure, Δf (1-2) when only the film tension is changed and Δf (1-3) when the holding area is changed are Δf (1-2) <Δf (1- 3), and Δf can be broadened accordingly. The dotted line is an example of the related art having only one resonance frequency.
[0044]
Thus, in the damping frequency range, the expansion spring is increased in this way, and when the liquid column resonance is generated by the damping orifice, the film tension of the internal pressure absorbing film is controlled to control the change in the resonance frequency. Can have a high phase, so that the resonance frequency originally depends on the deformation amount and deformation speed of the liquid ring vibration isolator, but the resonance frequency can be kept constant by the high phase. And the frequency dependency can be eliminated.
[0045]
In the idling frequency range, vector control is required to suppress bending vibration on the vehicle body side.However, since the resonance frequency is widened and the phase becomes higher as the resonance frequency becomes higher, vector control becomes possible. Therefore, bending vibration of the vehicle body can be effectively suppressed.
[0046]
FIG. 10 shows a third embodiment, in which the upper member 10 is provided with a deformation restricting portion 10a of the internal pressure absorbing film 17 on the side of the main liquid chamber 5 and an initial clearance C1 is provided between the upper member 10 and the internal pressure absorbing film 17 to provide a large input. The internal pressure absorbing film 17 can be configured to restrict excessive deformation (absorption of internal pressure).
[0047]
In addition, an initial clearance C2 may be provided between the tip of the pressing portion 20 that changes the pressing area and the internal pressure absorbing film 17 so as to restrict the deformation of the film beyond free deformation.
[0048]
FIG. 11 shows a fourth embodiment relating to the regulation of the external deformation of the internal pressure absorbing film 17, in which a stopper 17a which is formed integrally with the internal pressure absorbing film 17 and forms a ring-shaped leg which opens obliquely in the outer peripheral direction is provided. The pressing member 20 is pressed against the stroke passage 28. With this configuration, when the internal pressure absorbing film 17 is bent toward the pressing member 20 and elastically deforms, the stopper 17a is strongly pressed against the stroke passage 28 and stretches as the amount of elastic deformation increases. The expansion spring can be increased by making it difficult to deform, and the input to the internal pressure absorbing film 17 can be dispersed to increase the internal pressure. In addition, since the stopper 17a is always in contact with the stroke passage 28, a structure for preventing interference noise with the pressing member 20 can be achieved.
[0049]
In addition, by making the cross-sectional shape on the side of the internal pressure absorbing film 17 irregular, a change of the expansion spring according to the stroke amount of the pressing member 20 can be realized. The stopper 17a in FIG. 11 is a specific example of this. Further, a columnar positioning portion 17b may be integrally formed at the center of the internal pressure absorbing film 17 so as to protrude. The projecting end of the positioning portion 17b is fitted into a positioning recess 25e provided on the top 25a of the pressing member 20. In this manner, the displacement of the pressing member 20 due to the stroke can be prevented, and the initial deformation portion is formed at a stage where the stroke amount is small.
[0050]
The present invention is not limited to the above embodiments, and various modifications and applications are possible within the principle of the present invention. For example, various types of driving means for the pressing member are possible, but it is also possible to use the negative suction pressure of the engine. In this case, the air is supplied instantaneously from the intake passage side serving as a negative pressure supply source. Further, the present invention can be applied to an appropriate liquid-sealed vibration isolator other than the engine mount.
[Brief description of the drawings]
FIG. 1 is a top view of a liquid-sealed engine mount according to an embodiment; FIG. 2 is a sectional view taken along line 2-2 of FIG. 1; FIG. 3 is a view showing a membrane tension control structure according to a first embodiment; 4 is an explanatory diagram of the film tension control. FIG. 5 is a graph showing a change in the holding area and the film tension. FIG. 6 is a diagram corresponding to FIG. 3 according to the second embodiment. FIG. 7 is a diagram according to the second embodiment. FIG. 8 is a diagram corresponding to FIG. 5 according to the second embodiment. FIG. 9 is a graph showing a widening of the resonance frequency. FIG. 10 is a diagram showing a film tension control structure according to the third embodiment. FIG. 11 is a diagram showing a membrane tension control structure according to a fourth embodiment. FIG. 12 is a diagram showing the principle of controlling an internal pressure absorbing film in a conventional example. FIG. 13 is a graph showing a change in resonance frequency in a conventional example. Diagram for explaining tension control [Description of symbols] 1: Liquid ring engine mount, 2: First mounting bracket, 3: Second mounting Tools, 4: Insulator, 5: Main liquid chamber, 6: Partition member, 7: Damping orifice, 8: Sub liquid chamber 7, 9: Diaphragm, 13: Idle orifice, 17: Internal pressure absorbing film, 18: Membrane tension variable means , 20: pressing member, 22: solenoid, 25: pressing surface

Claims (8)

A first mounting member mounted on the vibration source side, a second mounting member mounted on the vibration receiving side, an insulator interposed therebetween for absorbing vibration, and a liquid in which the insulator forms part of a wall. And a liquid chamber is divided into a main liquid chamber and a sub liquid chamber and communicated via a resonance orifice.
In a liquid ring vibration isolator provided with an internal pressure absorbing film made of an elastic film that elastically deforms and absorbs a change in internal pressure on a part of a wall surrounding the main liquid chamber,
It is provided with a pressing member pressed against the internal pressure absorbing film, and provided with a film tension variable means for changing the tension of the internal pressure absorbing film continuously or in multiple stages according to the advance / retreat stroke amount of the pressing member. Characteristic liquid ring vibration isolator. 2. The liquid ring vibration isolator according to claim 1, wherein the pressing surface shape of the pressing member changes substantially stepwise. 2. The liquid ring vibration isolator according to claim 1, wherein the cross-sectional shape of the internal pressure absorbing film changes irregularly. 4. The liquid ring vibration isolator according to claim 3, wherein a deformation regulating stopper is provided on the internal pressure absorbing film to make the cross-sectional shape irregular. 4. The liquid ring vibration isolator according to claim 3, wherein a positioning portion is provided at a central portion of the internal pressure absorbing film to make the cross-sectional shape irregular. The liquid ring vibration isolator according to any one of claims 1 to 5, wherein the resonance orifice is an idle orifice, and is used for controlling a resonance frequency thereof. The liquid ring vibration isolator according to any one of claims 1 to 5, wherein the resonance orifice is a damping orifice, and is used to eliminate the frequency dependence of the liquid column resonance. The liquid ring vibration isolator according to any one of claims 1 to 7, wherein a driving unit of the pressing member is a solenoid or an intake negative pressure.

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