JPH0389043A - Fluid-filled vibration isolating mount - Google Patents

Abstract

PURPOSE:To obtain a desired vibration isolating characteristic selectively according to inputted vibration by forming an orifice passage of three orifice passages, mutually different in the cross-sectional area/length ratio, provided at partition members, as well as providing a multi-stage switching valve means. CONSTITUTION:In the state of a valve body 64 being held in a protruding position, a pressure receiving chamber 34 and a balance chamber 36 are communicated through a first and a second orifice passages 56, 58, but because of the cross sectional area/length ratio of the passage 56 being small and its flow resistance being large compared to those of the passage 58, the vibration of a fluid between the chambers 34, 36 at the time of vibration input is solely generated in the passage 58, thereby displaying low-moving spring effect on the inputted vibration in an intermediate frequency band: In the state of the valve body 64 being held in an intermediate position, the chambers 34, 36 are communicated only through the passage 56, thus displaying damping effect on inputted vibration in a low frequency band. In the state of the valve body 64 being held in a contracting position, the chambers 34, 36 are communicated through the passage 56 and a third orifice passage 62, and vibration is damped by the passage 62 because of the above mentioned ratio.

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a vibration isolating mount that obtains a predetermined vibration isolating effect based on the flow of a fluid sealed therein, and is particularly effective in the flow of such a fluid. The present invention relates to a fluid-filled vibration-isolating mount whose vibration-isolating effect can be switched and controlled.

(Background technology) In recent years, the required characteristics for various vibration-isolating coupling bodies have become more sophisticated, and it has become difficult for conventional anti-vibration rubber, which relied exclusively on rubber elastic bodies, to provide the vibration-isolating function. Many studies and improvements have been made to this, and as one measure, encapsulation of fluid has been proposed.

As a type of vibration-proof connecting body sealed with such a fluid, as shown in Japanese Patent Application Laid-open No. 53-53'76, etc., a vibration-proof connecting body is attached to each member to be vibration-proof connected, and is attached in the direction of vibration input. A first support metal fitting and a second support metal fitting arranged opposite to each other with a predetermined distance apart are integrally connected by a rubber elastic body interposed between them, and the first and second support metal fittings are integrally connected. An orifice passageway that forms a pressure receiving chamber in which a predetermined incompressible fluid is sealed between the metal fittings and in which vibration is manually applied and an equilibrium chamber whose volume is variable, and further communicates the pressure receiving chamber and the equilibrium chamber with each other. A fluid-filled anti-vibration mount having a structure is known. In other words, in such a fluid-filled vibration isolating mount, the rubber elastic body alone is not sufficient, based on the resonance effect of the fluid that is caused to flow in the orifice passage when vibration is input between the first and second support fittings. This results in an excellent anti-vibration effect that is previously unavailable.

By the way, such anti-vibration mounts are suitably used, for example, as engine mounts and differential mounts for automobiles, but normally, anti-vibration mounts used for such parts are Multiple types of vibrations are manually generated depending on the dog's behavior, etc., and in order to effectively dampen each vibration,
Different vibration isolation characteristics may be required. For example, automotive engine mounts are required to have low dynamic spring characteristics to withstand idling vibrations of about 20 to 30 Hz that are input when the vehicle is stopped, while low dynamic spring characteristics are required to withstand idling vibrations of about 20 to 30 Hz that are input when the vehicle is stopped. High damping characteristics are required for front and rear low frequency vibrations, and low dynamic spring characteristics are required for high frequency vibrations of around 1007, such as muffled sounds.

However, in the conventional fluid-filled vibration isolation mount as described above, the vibration isolation effect due to the resonance effect of the fluid can only be effectively exhibited in the limited frequency range set in the orifice passage. For example, if the orifice passage is tuned so that a high damping effect can be exerted by the resonance effect of the fluid flowing inside it when vibration is input in the low frequency range corresponding to engine shake, etc., the When vibrations in the frequency range are input, the flow resistance of the fluid through the orifice passage increases significantly, causing the mount to have a significantly higher dynamic spring, which reduces vibration isolation performance against medium to high frequency vibrations such as idling vibrations and muffled noise. The problem was that the amount of water was significantly reduced.

In addition, in order to avoid the high movement spring of the mount due to such blockage of the orifice passage, Japanese Patent Laid-Open No. 57-9
340, etc., a movable member to which the liquid pressure in the pressure receiving chamber is applied to one surface and the liquid pressure in the equilibrium chamber to the other surface is applied to a partition wall that partitions the pressure receiving chamber and the equilibrium chamber. ,
It has been disclosed that the movable member is disposed and held so that it can be displaced by a predetermined dimension, thereby eliminating an increase in hydraulic pressure within the pressure receiving chamber based on the displacement of the movable member.

However, due to the structure of such a hydraulic pressure absorption mechanism using a movable member, vibrations that have a small difference in amplitude from vibrations that should be damped by the fluid flowing inside the orifice passage can be suppressed by the orifice passage. It is difficult to tune the vibration damping effect without impairing it, and it is difficult to obtain that effect. Therefore, for example, as mentioned above, when the orifice passage is made to flow through the inside of the orifice passage, it is difficult to tune the vibration damping effect. When tuned in such a way that a vibration damping effect can be achieved, it is extremely difficult to prevent the mount from becoming a highly dynamic spring even with such a hydraulic pressure absorption mechanism for idling vibrations having an amplitude close to that. It is.

Furthermore, in such a liquid pressure absorption mechanism, even when low frequency vibration is input, in which the vibration damping effect of the fluid flowing in the orifice passage should be exhibited, the liquid in the pressure receiving chamber is reduced by the amount of displacement of the movable member. This also has the disadvantage that the pressure is absorbed and the amount of fluid that can be made to flow through the orifice passage is reduced accordingly, resulting in a reduction in the vibration damping effect of the orifice passage.

(Problem to be solved) Here, the present invention has been made against the background of the above-mentioned circumstances, and the problem to be solved is:
To provide a fluid-filled vibration isolation mount that can switch and control the vibration isolation effect exerted based on the flow of fluid and selectively obtain desired vibration isolation characteristics according to input vibration. be.

(Solution Means) In order to solve this problem, in the present invention, the vibration input direction is provided with:
A first support metal fitting and a second support metal fitting respectively attached to the members to be vibration-isolated and connected are integrally connected by a rubber elastic body interposed between them, and
a pressure-receiving chamber that is supported by the second support fittings and is arranged with a partition member disposed in a direction substantially perpendicular to the vibration input direction, in which internal pressure fluctuations are generated due to elastic deformation of the rubber elastic body when vibration is input; A variable volume equilibrium chamber, at least a portion of which is defined by a flexible membrane, is formed on the side of the first support fitting, and a variable volume equilibrium chamber is formed on the opposite side of the pressure receiving chamber, and the pressure receiving chamber and the equilibrium chamber are connected to each other. In a fluid-filled vibration damping mount, the fluid-filled vibration isolating mount is provided with a predetermined incompressible fluid and an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other. , consisting of three orifice passages with different cross-sectional area/length ratios, and the communication state of at least two orifice passages excluding the one with the minimum cross-sectional area/length ratio. controlling multi-stage switching valve means, the multi-stage switching valve means jointly blocking fluid flow between the pressure receiving chamber and the equilibrium chamber through the two orifice passages; Its feature is that it is constructed in such a way that it is uniformly permissible.

Furthermore, in the present invention, among the three orifice passages, the orifice passage with the largest cross-sectional area/length ratio is
The pressure receiving chamber and the equilibrium chamber each communicate with each other through a communication space that extends in a direction substantially perpendicular to the vibration input direction, and inside the communication space, the vibration input direction a fluid enclosure which accommodates and arranges a movable member that is displaceable by a predetermined distance and that closes a communication hole of the communication cavity to the pressure receiving chamber or the equilibrium chamber by contacting the inner surface of the communication cavity; Another feature is the anti-vibration mount.

(Examples) Hereinafter, in order to clarify the present invention more specifically, examples of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 and 2 show an embodiment of an automobile engine mount having a structure according to the present invention. In these figures, 10 and 12 are a first support metal fitting and a second support metal fitting, and - vibration manual force direction (
They are arranged facing each other at a predetermined distance in the vertical direction in FIG. A second support 10.12 is elastically connected. Although not shown in the drawings, in this engine mount, the first and second support fittings 10.12 are attached to either the vehicle body side or the engine unit side, and there is an intermediary between them. This allows the engine unit to be supported against vibrations in the vehicle body.

More specifically, the first support fitting 10 is formed in a substantially circular flat plate shape, and a stopper portion 16 extending outward is integrally provided on the outer peripheral edge thereof. . On the other hand, the second support fitting 12 is formed in a cylindrical shape with a bottom, and an outer flange portion 18 that extends outward in the radial direction is integrally provided at the peripheral edge of the opening.

These first support fittings 10 and second support fittings 1
2 is a state in which the second support metal fitting 12 opens toward the first support metal fitting 10, and is arranged facing each other at a predetermined distance. Further, a mounting bolt 20 is attached to the first support fitting 10 at a substantially central portion thereof, protruding outward, while a mounting bolt 22 is attached to the second support fitting 12 at its bottom. These mounting bolts 20.22
Accordingly, the first and second support fittings 1O112 are attached to either the vehicle body side or the engine unit side, respectively.

Further, the rubber elastic body 14 is formed in a substantially cylindrical shape with a bottom, and at the axial center of the cylinder wall,
A regulating fitting 24 in the shape of an annular plate is placed under the embedding state and vulcanized and bonded thereto, while a connecting fitting 26 in the form of an annular plate with a caulking portion is provided at the peripheral edge on the opening side. Further, on the axially outer surface of the bottom side, the first support fitting 10 is provided.
are integrally provided by being vulcanized and bonded, respectively. Note that the rubber elastic body 14 is formed to extend onto the surface of the stopper portion 16 provided on the first support fitting 10, so that the stopper portion 16
A cushioning rubber portion 28 is formed to cover the surface of.

In such a rubber elastic body 14, the connecting fitting 2
6 is caulked and fixed to the outer flange portion of the second support metal fitting 12, and the opening thereof is fixedly attached to the second support metal fitting 12, whereby the first support metal fitting 10 and the second support metal fitting 12, and integrally connects both metal fittings 10 and 12.

Further, at the opening of the rubber elastic body 14, a diaphragm 3 made of a rubber elastic membrane having a thin circular sheet shape is provided.
0 is arranged, and its outer peripheral edge is connected to the connecting fitting 26.
It is attached to the second support fitting 12 by being clamped by the caulking portion. The opening of the rubber elastic body 14 is liquid-tightly closed by the diaphragm 30, and thereby the rubber elastic body 1
The interior of 4 is sealed from the outside space.

Note that there is a space between the diaphragm 30 and the second support fitting 12, which allows the diaphragm 30 to expand and deform.
A space 31 with a predetermined volume is defined.

Furthermore, inside this sealed rubber elastic body 14,
A predetermined incompressible fluid such as water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixture thereof is sealed, thereby forming a fluid chamber within the rubber elastic body 14. Incidentally, such fluid can be advantageously sealed by, for example, caulking and fixing the connecting fitting 26 to the second supporting fitting 12 in a predetermined fluid.

Further, within the fluid chamber, a partition member 32 having a substantially bottomed cylindrical shape is held at its opening side peripheral edge together with the diaphragm 30 by the caulking portion of the connecting fitting 26 against the second support fitting 12. As a result, it is arranged so as to protrude toward the first support metal fitting 10 side.

That is, the fluid chamber is partitioned into two chambers by the partition member 32, and the peripheral wall portion is made of rubber elastic material on the first support fitting 10 side with the partition member 32 in between. 14, and a pressure receiving chamber 34 is formed in which an internal pressure fluctuation is generated based on the elastic deformation of the rubber elastic body 14 when vibration is input. A diaphragm 30 forms a variable volume equilibrium chamber 36 in which internal pressure fluctuations are absorbed or reduced based on the elastic deformation of the diaphragm 30.

Further, the partition member 32 is constructed by axially overlapping an upper partition fitting 38 and a lower partition fitting 40, each of which has a substantially bottomed cylindrical shape.

In the cylindrical wall portion of the partition member 32, an annular space 48 is formed between the overlapping surfaces of the upper and lower partition fittings 38, 40, and extends approximately along the circumference in the circumferential direction. Inside the annular space 48 is a through hole 5 provided in the upper partition fitting 38 at one end in the circumferential direction.
0, while communicating with the inside of the pressure receiving chamber 34,
The intermediate portion in the circumferential direction and the other end portion in the circumferential direction are communicated with the equilibrium chamber 36 through a through hole 52 and a through hole 54 provided in the lower partition fitting 40, respectively.

That is, thereby, within such annular cavity 48,
A first orifice passage 56 and a second orifice passage are provided between the through holes 50 and 54 and between the through holes 50 and 52 to allow fluid to flow between the pressure receiving chamber 34 and the equilibrium chamber 36. Two orifice passages 58 are respectively formed, and these first and second orifice passages 56
．． 58 are formed with different predetermined lengths, and the first orifice passage 56 is set to have a smaller ratio (cross-sectional area/length) than the second orifice passage 58. And such first orifice passage 5
Based on the resonance effect of the fluid flowing through the second orifice passage 58, a high damping effect against low frequency vibrations of around 10 Hz corresponding to shake etc. can be exhibited. Based on the action, a low dynamic spring effect can be exerted against medium frequency vibrations of about 20 to 30 Hz, which corresponds to idling vibrations.
Each one is tuned.

Furthermore, in the bottom wall of the partition member 32, a communicating space 42 having a disc shape with a predetermined thickness is formed between the overlapping surfaces of the upper and lower partition fittings 38, 40, and the inside thereof is Through hole 44 formed in upper and lower partition fittings 38 and 40
．． 46-, the pressure receiving chamber 34 and the equilibrium chamber 36 are communicated with each other. Furthermore, a movable plate 60 having a substantially disk shape is housed in the communication space 42 so as to be movable by a predetermined distance.

That is, thereby, there is a space between the pressure receiving chamber 34 and the equilibrium chamber 36 that allows substantial fluid flow through the through holes 44.46 based on the displacement of the movable plate 60. Three orifice passages 62 are formed. In the third orifice passage 62, the ratio (cross-sectional area/length) thereof is set to be larger than that of the second orifice passage 58, so that the flow can be caused inside the third orifice passage 62. Based on the resonance effect of the fluid, it is tuned so that a low dynamic spring effect can be exhibited against high frequency vibrations of around 100 Hz.

Further, a valve body 64 having a substantially disk shape is accommodated in the equilibrium chamber 36, while a protruding position is located inside the space 31 formed in the second support fitting 12. A drive motor 68 having an output shaft 66 that can be switched in three axial stages is housed, and the output shaft 66 extends in the direction opposite to the first and second support fittings 10 and 12.
The second support fitting 12 is attached via the annular plate-shaped holding fitting 70.
is fixedly attached to. In addition, in the figure, 7
2 is a lead wire for supplying electricity to the drive motor 68.

The output shaft 66 of the drive motor 68 is connected to the valve body 6.
4, the valve body 64
However, according to the operation of the drive motor 68, inside the equilibrium chamber 36,
The position of the first support metal fitting 10 and the second support metal fitting 12 can be controlled in three stages in the opposing direction. Note that the valve element 64 is integrally vulcanized and bonded to the diaphragm 30 on its lower surface, thereby ensuring liquid tightness of the equilibrium chamber 36.

The valve body 64 also has a central portion of its upper surface that protrudes at a predetermined height in the axial direction toward the bottom wall of the partition member 32, and is inserted into the through hole 46 provided in the bottom wall. As a result, an axial protrusion 74 capable of closing the through hole 46 is provided, and at its outer peripheral edge, it protrudes radially toward the peripheral wall of the partition member 32, and the inner surface of the lower partition fitting 40 A radial protrusion 76 is provided that can close the through hole 52 by coming into contact with the opening portion of the through hole 52 .

The valve body 64 is positioned by the drive motor 68, so that the through hole 46 and the through hole 52 are communicated/blocked depending on the position. It is. More specifically, in the protruding position where the output shaft 66 of the drive motor 68 is most protruded, the valve body 64 has its axial protrusion 74 as shown in FIGS. 1 and 2. is inserted into the through hole 46 of the partition member 32 to close the through hole 46, while its radial protrusion 76 is positioned on the bottom side of the partition member 32 and is provided on the lower partition fitting 40. The through hole 52 is maintained in an open state. In addition, in the intermediate position where the output shaft 66 of the drive motor 68 is in the intermediate protruding state, the axial protrusion 74 of the valve body 64 is inserted into the through hole 46 as shown in the third jump. While closing the through hole 46, the radial protrusion 76
is brought into contact with the opening of the through hole 52, so that the through hole 5
It is designed to block 2. Furthermore, in the retracted position where the output shaft 66 of the drive motor 68 is retracted, the axial protrusion 74 of the valve body 64 is removed from the through hole 46, as shown in FIG. , while opening the through hole 46, when the radial protrusion 76 comes into contact with it,
The through hole 52 is closed.

That is, as shown in FIGS. 1 and 2, when the valve body 64 is held in the protruding position, the inside of the pressure receiving chamber 34 and the inside of the equilibrium chamber 36 are connected to the first orifice passage 56.
and through the second orifice passageway 58, respectively.
Although they are communicated with each other, the first orifice passage 5G is (
Since the ratio of cross-sectional area/length (cross-sectional area/length) is small and the flow resistance is large, fluid flow between the pressure receiving chamber 34 and the equilibrium chamber 36 during vibration input occurs exclusively within the second orifice passage 58. It will be done. Therefore, under such conditions, based on the resonance effect of the fluid flowing through the second orifice passage 58, the low-motion spring responds to the input vibration in the medium frequency range of about 20 to 30 degrees Celsius, which corresponds to idling vibration. It can be effective.

Furthermore, while the valve body 64 is held in the protruding position, the third orifice passage 62 is blocked, and the pressure inside the pressure receiving chamber 34 due to the flow of fluid through the third orifice passage 62 is blocked. Since escape of hydraulic pressure is completely prevented, the low motion spring effect of the fluid flowing through the second orifice passage 58 is not inhibited by the third orifice passage. be.

Further, as shown in FIG. 3, when the valve body 64 is held at the intermediate position, the pressure receiving chamber 34 and the equilibrium chamber 36 are connected only through the first orifice passage 56.
The pressure receiving chambers 34 are communicated with each other and are connected to each other during vibration input.
Fluid flow between the balance chamber 36 and the second orifice passage 56 occurs exclusively within the second orifice passage 56. Therefore, under such conditions, based on the resonance effect of the fluid flowing through the first orifice passage 56,
A damping effect can be exerted on input vibrations in a low frequency range of about 10 Hz, which corresponds to shakes and the like. Also, since the third orifice passage 62 is blocked at the intermediate position of the valve body 64, the damping effect of the fluid flowing through the first orifice passage 56 is It is not obstructed by the passage 62.

Furthermore, as shown in FIG. 4, the valve body 64
When the pressure receiving chamber 34 and the equilibrium chamber 36 are held in the contracted position, the interior of the pressure receiving chamber 34 and the interior of the equilibrium chamber 36 are communicated with each other through the first orifice passage 56 and the third orifice passage 62, respectively. No. 1 orifice passage 56
has a smaller (cross-sectional area/length) ratio and greater flow resistance than the No. 30 orifice passage 62, so the fluid flow between the pressure receiving chamber 34 and the equilibrium chamber 36 during vibration input is reduced. is produced exclusively within the third orifice passage 62. Therefore, under such conditions, based on the resonance effect of the fluid flowing in the third orifice passage 62, a low dynamic spring effect against human vibration in the high frequency range after 100 Hz, which corresponds to muffled noise, etc. can be demonstrated.

In addition, regarding the engine mount in this example,
Since the movable plate 60 disposed within the communication cavity 42 can restrict the amount of fluid flowing through the third orifice passage 62,
Even when the valve body 64 is held in the contracted position, the third orifice passage 62 is substantially blocked by the movable plate 60 when a low-frequency, large-amplitude vibration equivalent to a shake is input. As a result, a fluid flow is generated in the first orifice passage 56, and a high damping effect based on the resonance effect can be effectively exhibited.

Therefore, in the engine mount having the above-described structure, the output value of the vehicle's speed sensor, acceleration sensor, or road surface sensor, etc. Based on this, by operating the drive motor 68 and controlling the position of the valve body 64, vibration damping characteristics corresponding to the input vibration can be effectively exhibited, thereby suppressing idling vibration, muffled noise, etc. Both low dynamic spring characteristics against high frequency vibrations and high damping characteristics against low frequency vibrations such as shaking can be extremely advantageously achieved based on the resonance effect of the fluid.

Although the embodiments of the present invention have been described in detail above, these are literal illustrations, and the present invention is not to be construed as being limited only to these specific examples.

For example, the specific form and structure of the three orifice passages 56, 58, and 62 are not limited in any way, and may be determined as appropriate depending on the required vibration damping characteristics, mount shape, etc. It is also possible to form the first orifice passage 56 and the second orifice passage 58 independently of each other.

Furthermore, when a damping effect against low frequency, large amplitude vibrations is not required when high frequency, small amplitude vibrations are input, it is not necessary to provide the movable plate 60 for the third orifice passage 62.

Furthermore, the multi-stage switching valve means for switching and controlling the three orifice passages 56, 58, and 62 is not limited to that of the embodiment described above. It is also possible to perform the rotation by rotating the body, or to use a solenoid means, pneumatic means, etc. instead of the drive motor 68.

Furthermore, the first orifice passage 56 having the smallest ratio (cross-sectional area/length) may also be controlled to communicate/block depending on its utilization status.

In addition, it goes without saying that the present invention can be well applied to automobile engine mounts as illustrated, as well as automobile differential mounts, and vibration-proof mounts for various devices other than automobiles.

In addition, although not listed, the present invention can be implemented in embodiments with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and such embodiments may be different from the present invention. It goes without saying that any of these are included within the scope of the present invention as long as they do not depart from the spirit of the invention.

(Effects of the Invention) As is clear from the above description, in the fluid-filled vibration damping mount according to the present invention, the switching control of the orifice passage by the multi-stage switching valve means allows the fluid-filled vibration damping mount to switch between the appropriate one of the orifice passages according to the input vibration. orifice passages can be selectively utilized, thereby providing, for example, a high damping effect on low-frequency vibrations due to the resonant action of the fluid flowed in the first orifice passage; A low dynamic spring effect on medium frequency vibrations based on the resonance effect of the fluid flowing in the passage, and a low dynamic spring effect on high frequency vibrations based on the resonance effect of the fluid flowing in the third orifice passage are input. This can be achieved selectively depending on the vibration, and extremely good vibration isolation performance can be exhibited against human vibration over a wide frequency range.

Further, the fluid according to the present invention is arranged such that a movable member is accommodated in a third orifice passage (communicating space) which is set to have the largest cross-sectional area/length ratio among the three orifice passages. In the enclosed type anti-vibration mount, the third orifice passage can be substantially closed when the movable member comes into contact with the inner surface of the communication cavity, so even when the third orifice passage is open, When low-frequency, large-amplitude vibrations are input, it is possible to advantageously obtain a vibration-damping effect based on the resonance effect of the fluid flowing through the separate orifice passage.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing an engine mount according to an embodiment of the present invention, and corresponds to the I■ cross section in FIG. 2. FIG. It is a diagram. 3 and 4 are longitudinal cross-sectional views of the engine mount shown in FIG. 1 in different operating states. 10: First support fitting 12: Second support fitting 14: Rubber elastic body 30: Diaphragm 32: Partition member
34: Pressure receiving chamber 36: Equilibrium chamber 42: Communication cavity 44. 46: Through hole 48: Annular cavity 50. 52, 54: Through hole 56: First orifice passage 58: Second orifice passage 60: Movable plate 62: Third orifice passage 64: Valve body 66: Output shaft 68: Drive motor

Claims (2)

[Claims] (1) A first support metal fitting and a second support metal fitting are interposed between the first support metal fittings and the second support metal fittings that are respectively attached to the members to be vibration-isolated and connected, and are arranged facing each other at a predetermined distance in the vibration input direction. The rubber elastic body is integrally connected with the rubber elastic body and is supported by the second support metal fitting and is disposed in a direction substantially perpendicular to the vibration input direction with a partition member in between. A pressure-receiving chamber in which internal pressure fluctuations occur due to elastic deformation of the pressure-receiving chamber is on the side of the first support fitting, and a volume-variable equilibrium chamber, at least a portion of which is defined by a flexible membrane, is on the opposite side of the pressure-receiving chamber. In a fluid-filled vibration isolation mount, the pressure receiving chamber and the equilibrium chamber are respectively formed, and a predetermined incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and an orifice passage is provided to communicate the pressure receiving chamber and the equilibrium chamber with each other. , the orifice passage is constituted by three orifice passages provided in the partition member and having different cross-sectional area/length ratios, and among the orifice passages, at least the cross-sectional area/length ratio is A multi-stage switching valve means is provided for controlling the communication state of two orifice passages other than the smallest one, and the multi-stage switching valve means controls communication between the pressure receiving chamber and the equilibrium chamber through the two orifice passages. 1. A fluid-filled vibration damping mount characterized in that the fluid-filled vibration isolating mount is configured to both prevent the flow of fluid at and to alternatively allow the flow of fluid. (2) Of the three orifice passages, the orifice passage with the largest cross-sectional area/length ratio is communicated with the inside of the pressure receiving chamber and the equilibrium chamber, respectively, and is substantially perpendicular to the vibration input direction. It is configured with a communicating cavity that expands in a direction, and can be displaced a predetermined distance in the vibration input direction inside the communicating cavity, and by contacting the inner surface of the communicating cavity, the vibration of the communicating cavity is expanded. 2. The fluid-filled vibration damping mount according to claim 1, further comprising a movable member for closing a communication hole with respect to the pressure receiving chamber or the equilibrium chamber.