JP2004069005A - Fluid-sealed type vibration damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid-sealed type vibration damper provided with a balance chamber connected to a pressure receiving chamber through a first orifice passage tuned to a low frequency range, and a vibration chamber connected to the pressure receiving chamber through a second orifice passage tuned to a middle frequency range, so that positive damping effect is achieved by applying pressure fluctuation generated in the vibration chamber based on air pressure fluctuation due to external causes to the pressure receiving chamber, in which positive vibration damping effect is effectively achieved to a wide range from middle to high frequencies, and in which deterioration of a vibration state caused by high-order components is avoided in providing positive damping effect to middle frequency vibration. <P>SOLUTION: A through-hole 82 is provided in a partition wall 52 parting the pressure receiving chamber 58 from the balance chamber 38, and a movable plate 84 is disposed on the through-hole 82. Outer circumferential edge parts of the movable plate 84 are held by holding grooves 86 with prescribed rattle. By clearance for the rattle between the holding groove 86 and the movable plate 84, a third orifice passage 90 is formed to be tuned to a high frequency range. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
【Technical field】
The present invention relates to a fluid-filled type vibration damping device in which a vibration damping effect is exerted based on a flow action and a pressure action of an incompressible fluid enclosed therein, and particularly to a pressure fluctuation of the sealed incompressible fluid. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid-filled type vibration damping device in which a vibration damping effect is obtained by externally performing active control according to vibration to be damped.
[0002]
[Background Art]
In the case of vibration-damping members, such as automobile bodies and various members, in which vibration (including noise caused by vibration) is a problem, in order to reduce the vibration, conventionally, the vibration member and the vibration-damping object are used. 2. Description of the Related Art An anti-vibration device such as an engine mount, which is interposed between members to reduce the transmission of vibration from a vibration member to a vibration-isolation target member, is used.
[0003]
As one type of such a vibration isolator, a pressure receiving chamber in which a part of a wall is formed of a main rubber elastic body to which vibration is input and pressure fluctuation is caused when vibration is input, and a flexible and easily deformable A part of the wall is made up of the membrane to form an equilibrium chamber where the volume change is allowed. The pressure receiving chamber and the equilibrium chamber are filled with an incompressible fluid such as water, and both chambers communicate with each other. There is known a fluid-filled type vibration damping device in which a first orifice passage is provided to obtain a passive vibration damping effect based on a flow action of a fluid which is caused to flow through the first orifice passage at the time of vibration input. I have. In recent years, in order to further improve the vibration isolation performance, a part of a wall portion is formed of an elastic vibration plate to form a vibration chamber in which an incompressible fluid is sealed. A second orifice passage communicating with the pressure receiving chamber is provided, and a working air chamber is formed on the opposite side of the vibrating chamber with the elastic vibrating plate interposed therebetween. There has been proposed a fluid filled type vibration damping device in which a vibration force is applied to an elastic vibration plate. In such a fluid-filled type vibration damping device, the pressure fluctuation generated in the vibration chamber by the vibration of the elastic vibration plate is actively controlled according to the vibration to be damped, and the second orifice passage is controlled. In this case, the vibration to be damped can be counteracted or positively reduced by applying the pressure to the pressure receiving chamber.
[0004]
By the way, in an automobile engine mount or the like, the input vibration changes in accordance with the vehicle running conditions and the like, and a vibration damping effect is required for each of these plural types of vibrations. Therefore, for example, in the prior art, the first orifice passage is tuned to low-frequency vibration corresponding to an engine shake or the like, and the flow action of the fluid that is caused to flow through the first orifice passage is used for the engine shake or the like. Tune the second orifice passage to medium-frequency vibrations equivalent to idling vibrations, etc., to prevent the fluid flowing through the second orifice passages against idling vibrations. It has been proposed to obtain an active vibration damping effect using a flow action.
[0005]
Furthermore, in recent years, further improvement in vibration isolation performance has been demanded, and as one measure to cope with such a demand, for example, for high-frequency vibration such as muffled sound and chatter vibration during traveling. It is conceivable that an active vibration damping effect can be obtained by exerting air pressure fluctuations in a frequency range corresponding to those vibrations on the working air chamber and controlling the pressure of the vibration chamber and the pressure receiving chamber.
[0006]
However, in the active type fluid filled type vibration damping device having the conventional structure as described above, the second orifice passage which exerts pressure fluctuation of the vibration chamber on the pressure receiving chamber is tuned to a middle frequency range corresponding to idling vibration or the like. From this, the transmission efficiency of pressure fluctuations in the higher frequency range becomes significantly lower due to the anti-resonant action of the second orifice passage. Therefore, even if high-frequency pressure fluctuations are caused in the vibration chamber, However, there is a problem that the pressure fluctuation is hard to be transmitted to the pressure receiving chamber, and it is difficult to effectively obtain a desired active vibration damping effect.
[0007]
In order to cope with such a problem, for example, the tuning frequency of the second orifice passage is set to a high frequency range corresponding to a muffled sound or the like. It is conceivable to improve the transmission efficiency of the elastic vibration plate to the middle frequency range by tuning the second orifice passage to the middle frequency range. There is a problem that the function in the second orifice passage, which has been performing the filter function of suppressing transmission of the higher-order component of the pressure fluctuation generated in the vibration chamber to the pressure receiving chamber, is not performed. That is, if the second orifice passage is tuned to a high frequency range corresponding to muffled sound, the pressure fluctuation caused in the vibration chamber by the pneumatic vibration of the elastic vibration plate in the high frequency range surely causes the pressure fluctuation in the pressure receiving chamber. It is possible to obtain an active vibration damping effect against vibrations in the high frequency range, but when the vibration damping effect is required for vibrations in the middle frequency range, When air pressure is applied in the frequency range, it is difficult to prevent high-order components of pressure fluctuations derived from the excitation chamber from being applied to the pressure receiving chamber through the second orifice passage. Therefore, higher-order pressure fluctuations that do not correspond to the above may be generated in the pressure receiving chamber, and the vibration state in the higher-order frequency range may be adversely deteriorated.
[0008]
Of course, for such a problem, as the second orifice passage that connects the pressure receiving chamber and the vibration chamber to each other, the second orifice passage is tuned to the middle frequency range equivalent to idling vibration, etc. A plurality of components or the like tuned to a corresponding high frequency range are formed in parallel with each other, and the plurality of second orifice passages are switched by valve means or the like to selectively operate according to vibration to be damped. It is also conceivable to deal with it. However, when such a structure is employed, a plurality of second orifice passages are formed, and valve means and an actuator for switching the plurality of second orifice passages are required. However, this is not always an effective measure because the increase in manufacturing cost and the like are serious problems.
[0009]
[Solution]
Here, the present invention has been made in view of the above-mentioned circumstances, and the problem to be solved is to exert an active vibration damping effect by applying an external air pressure fluctuation as described above. In the obtained fluid-filled type vibration damping device, the active vibration damping effect exerted by controlling the pressure in the pressure receiving chamber is improved with respect to a plurality of vibrations from a middle frequency range to a high frequency range or a vibration in a wide frequency range. Another object of the present invention is to provide a fluid-filled type vibration damping device having a novel structure, which can also be effectively obtained.
[0010]
[Solution]
Hereinafter, embodiments of the present invention made to solve such problems will be described. The components employed in each of the embodiments described below can be employed in any combination as much as possible. In addition, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or based on the invention ideas that can be understood by those skilled in the art from the descriptions. It should be understood that it is recognized on the basis of.
[0011]
That is, the features of the first aspect of the present invention are as follows: (a) a first mounting member and a second mounting member which are spaced apart from each other and respectively mounted on members to be vibration-isolated and connected; b) a main rubber elastic body for elastically connecting the first mounting member and the second mounting member; and (c) a part of the wall portion is formed by the main rubber elastic body, so that pressure fluctuation occurs at the time of vibration input. (D) a pressure receiving chamber filled with an incompressible fluid, and (d) an equilibrium chamber filled with an incompressible fluid, wherein a part of a wall is formed of a flexible membrane and volume change is allowed. (E) a first orifice passage for communicating the pressure receiving chamber and the equilibrium chamber with each other; and (f) a part of a wall portion formed on the opposite side of the pressure receiving chamber with a partition wall interposed therebetween. A vibrating chamber formed of a vibration plate and filled with an incompressible fluid; (H) an acting air chamber formed on the opposite side with respect to the vibration plate, which exerts a vibration force on the elastic vibration plate by exerting an air pressure fluctuation from the outside to generate a pressure fluctuation in the vibration chamber; A) a second orifice passage which is tuned to a higher frequency range than the first orifice passage and communicates the pressure receiving chamber and the vibration chamber with each other; and (i) a through hole is provided in the partition wall. An annular holding groove that opens to the inner peripheral side is formed at the peripheral portion of the movable member, and a hard movable plate is disposed in the through-hole, and the outer peripheral edge of the movable plate is inserted into the holding groove and has a predetermined play. The movable plate can be displaced in the holding groove by the play in the plate thickness direction by being gripped, and the movable plate is displaced in the plate thickness direction and abuts on the inner surface of the holding groove to form the through hole. Is substantially closed, and the holding groove is A movable orifice which can form a third orifice passage which wraps around the outer peripheral edge of the movable plate and connects the vibration chamber and the pressure receiving chamber to each other with a tuning frequency higher than that of the second orifice passage. And a plate mechanism.
[0012]
In such a fluid-filled type vibration damping device having a structure according to this aspect, relative vibration of a low frequency range is caused by relative pressure fluctuations induced between the pressure receiving chamber and the equilibrium chamber due to vibration input. While the passive vibration damping effect based on the resonance action of the fluid caused to flow through the first orifice passage is effectively exerted, the vibration resistance of the first orifice passage is significantly increased at the time of vibration input in a medium to high frequency range where the flow resistance is significantly increased. The pressure fluctuation generated in the vibration chamber by applying pressure fluctuation to the working air chamber to vibrate the elastic vibration plate is transmitted to the pressure receiving chamber through the second orifice passage or the third orifice passage, By actively controlling the pressure fluctuation in the pressure receiving chamber in accordance with the vibration to be damped, a destructive or positive damping effect can be obtained.
[0013]
Here, the input vibration in the middle frequency range often has a larger amplitude than the input vibration in the high frequency range, and particularly in automobiles, the amplitude of idling vibration, which tends to be a problem in the middle frequency range, is high in the high frequency range. It is sufficiently large compared to the amplitude of vibrations such as running muffled sounds and chattering sounds that are likely to cause problems. Therefore, when damping vibration in the middle frequency range, the pressure fluctuation generated in the vibration chamber by the air pressure vibration of the elastic vibration plate is increased according to the magnitude of the vibration amplitude to be vibration-proof. Therefore, the vibration plate constituting the wall portion of the vibration chamber is also displaced greatly, and is brought into contact with the holding groove of the partition. As a result, the third orifice passage is closed, and the fluid flow through the second orifice passage is efficiently caused between the vibration chamber and the pressure receiving chamber, so that the desired active vibration damping effect is achieved. And the transmission of higher-order components of pressure fluctuations induced in the vibration chamber through the third orifice passage can be avoided. On the other hand, when the vibration in the high frequency range is damped, the fluid flow resistance of the second orifice passage is significantly increased due to the anti-resonant action, but is generated in the vibration chamber by the air pressure vibration of the elastic vibration plate. Since the pressure fluctuation is reduced according to the magnitude of the vibration amplitude to be damped, the vibration plate is difficult to follow up to high frequencies, and the vibration plate is placed in the holding groove of the partition wall. It is almost in a floating state. As a result, the third orifice passage is in a communicating state, and the fluid flow through the third orifice passage is efficiently caused between the vibration chamber and the pressure receiving chamber, and the desired active vibration damping effect is achieved. Can be advantageously exerted based on the flow action of
[0014]
Therefore, in the fluid-filled type vibration damping device of this aspect, the vibration to be damped is applied to the vibration in the middle to high frequency range where the passive vibration damping effect by the first orifice passage is not sufficiently exerted. By adjusting the frequency and amplitude of the pressure fluctuation generated in the vibration chamber by the pneumatic vibration of the elastic vibration plate accordingly, the second orifice passage and the third orifice passage are automatically adjusted accordingly. Therefore, even when the vibration to be damped is over a plurality of or a wide frequency range, the pressure fluctuation caused in the vibration chamber by the pneumatic vibration of the elastic vibration plate is selected. It is possible to control the pressure in the pressure receiving chamber by transmitting it to the pressure receiving chamber while avoiding a significant decrease in the vibration isolation performance due to higher order components, and it is possible to control vibrations in multiple or wide frequency ranges. Active vibration isolation Result is as it can be effectively exhibited.
[0015]
According to a second aspect of the present invention, in the fluid-filled type vibration damping device according to the first aspect, the inner surface of the holding groove formed in the partition and the holding groove when the movable plate is displaced. A cushioning rubber layer is provided on at least one of an outer peripheral edge portion of the movable plate and an inner surface of the movable plate. In this embodiment, the impact sound and impact when the vibration plate abuts on the holding groove can be reduced or avoided by the buffering action of the buffer rubber layer.
[0016]
According to a third aspect of the present invention, in the fluid-filled type vibration damping device according to the first or second aspect, the outer peripheral edge of the movable plate is formed in a circumferential direction with an outer peripheral shape of a substantially circular arc cross section. The third orifice passage is formed by extending the holding groove so as to extend in the circumferential direction with an inner circumferential surface shape having a substantially arc-shaped cross section slightly larger than the outer circumferential surface of the movable plate. Is formed between the outer peripheral surface of the movable plate and the inner peripheral surface of the holding groove in a substantially arc-shaped flow path form. In this aspect, in addition to advantageously securing the length of the third orifice passage, the shape of the third orifice passage in the fluid flow direction can be a smooth shape without a bent portion. Thus, by suppressing the flow resistance of the fluid, it is possible to more efficiently obtain an active vibration isolation effect based on the flow action of the fluid. In order to make the outer peripheral edge of the movable plate have an arc-shaped outer peripheral surface, for example, a rubber elastic body is fixed to the outer peripheral edge of the movable plate, and the outer peripheral edge of the movable plate has a circular cross section. It can be advantageously formed by providing an annular projection projecting from the above, and such an annular projection can be used as the cushioning rubber layer in the second aspect.
[0017]
According to a fourth aspect of the present invention, there is provided the fluid filled type vibration damping device according to any one of the first to third aspects, wherein air pressure fluctuation is applied to the working air chamber in a tuning frequency range of the second orifice passage. When the pressure fluctuation is caused in the vibration chamber by applying the pressure, the movable plate is brought into contact with the inner surfaces of the holding grooves on both sides in the plate thickness direction, while the third orifice passage is closed. When air pressure fluctuation is applied to the working air chamber in the tuning frequency range to cause pressure fluctuation in the vibration chamber, the amplitude in the thickness direction of the movable plate is smaller than the play of the movable plate with respect to the holding groove. The contact of the movable plate with the holding groove in the plate thickness direction is suppressed, and the third orifice passage is formed substantially constantly in the holding groove. I do. In this aspect, by considering the magnitude of the air pressure fluctuation exerted on the working air chamber according to the vibration to be damped, tuning according to the required damping characteristics can be advantageously achieved. It becomes.
[0018]
According to a fifth aspect of the present invention, in the fluid-filled type vibration damping device according to any one of the first to fourth aspects, the first orifice passage has a first intermediate portion in a longitudinal direction intermediate portion. A connection window that allows the orifice passage to communicate with the vibrating chamber is formed, so that the second orifice passage is formed using a part of the first orifice passage. I do. In such an embodiment, the first orifice passage and the second orifice passage can be formed compactly in a small space. More preferably, at least a part of the first orifice passage is formed so as to be located on the outer peripheral side of the movable plate and extend in the circumferential direction, whereby the passage length of the orifice passage is reduced in a small space. Can be secured more efficiently.
[0019]
According to a sixth aspect of the present invention, in the fluid filled type vibration damping device according to any one of the first to fifth aspects, one of the first mounting member and the second mounting member is connected to a power unit side. By attaching to the member and attaching the other to the body side member, an engine mount for supporting the power unit of the vehicle with vibration isolation against the body is configured, and the first orifice passage is set to a low frequency range corresponding to an engine shake. In addition to the tuning, the second orifice passage is tuned to a middle frequency range corresponding to idling vibration, and the third orifice passage is tuned to a high frequency range corresponding to a traveling muffled sound. In the engine mount having such a structure according to this aspect, a passive vibration damping effect can be effectively provided by the resonance effect of the fluid that is caused to flow through the first orifice passage against the engine shake that tends to be a problem when the vehicle is running. As well as exerting noise, chattering noise and chattering noise, which are likely to cause problems when the vehicle is running, the pressure fluctuations generated in the vibration chamber by the air pressure vibration of the elastic vibration plate are passed through the third orifice passage. By transmitting the pressure to the pressure receiving chamber and controlling the pressure fluctuation in the pressure receiving chamber, an active vibration isolation effect can be effectively exhibited. Further, for idling vibration which is likely to be a problem when the vehicle is stopped, pressure control is performed by transmitting the pressure fluctuation generated in the vibration chamber by the air pressure vibration of the elastic vibration plate to the pressure receiving chamber through the second orifice passage. As a result, an active vibration damping effect is exhibited, and in this case, compared to the pressure fluctuation generated in the vibration chamber when damping high frequency vibration corresponding to muffled noise, it corresponds to idling vibration etc. Pressure fluctuations generated in the vibration chamber during vibration isolation of medium-frequency vibrations have large amplitudes and large displacements of the vibration plate, and the third orifice passage is blocked by contact with the holding groove of the partition. Therefore, during vibration isolation of the medium-frequency vibration, the transmission of the higher-order components generated in the vibration chamber to the pressure-receiving chamber can be effectively suppressed, and the vibration state caused by the transmission of the higher-order components can be reduced. Reduction also as it can be advantageously avoided.
[0020]
A seventh aspect of the present invention is the fluid-filled type vibration damping device according to any one of the first to sixth aspects, wherein the second mounting member has a cylindrical shape, and the second mounting member has a cylindrical shape. The first mounting member is spaced apart from one of the openings, and the first mounting member and the second mounting member are connected to each other by the rubber elastic body. And the other opening in the axial direction of the second mounting member is fluid-tightly covered with the flexible film, while being overlapped with each other in the axial direction of the second mounting member. The combined first partition member and second partition member are fixedly supported by the second mounting member, and the pressure receiving chamber is formed between the first partition member and the main rubber elastic body. Forming the equilibrium chamber between the second partition member and the flexible membrane, and further comprising the second partition member. The working air chamber is formed by covering the recess provided on the superposed surface side of the member with the first partition member in a fluid-tight manner with the elastic vibration plate, and the elastic vibration plate and the first Wherein the vibration chamber is formed between the partition members. In this embodiment, the pressure receiving chamber, the equilibrium chamber, and the vibration chamber, each of which is filled with an incompressible fluid, and the working air chamber to which air pressure fluctuation is applied from the outside are formed with an efficient arrangement space. Accordingly, the fluid-filled vibration damping device structured according to the present invention can be realized in a compact manner.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.
[0022]
First, FIGS. 1 and 2 show an automobile engine mount 10 as one embodiment of the present invention. In this engine mount 10, a first mounting member 12 as a first mounting member and a second mounting member 14 as a second mounting member are spaced apart from each other. The second mounting bracket 14 has a structure in which the first mounting bracket 12 is mounted on the power unit side of the vehicle, while the second mounting bracket 14 is mounted on the body side of the vehicle. By attaching the power unit to the body, the power unit is supported for vibration isolation with respect to the body. In the following description, the vertical direction refers to the vertical direction in FIG. 1 in principle.
[0023]
More specifically, the first mounting member 12 has a substantially inverted truncated conical shape, and a nut portion 15 protruding upward in the axial direction is integrally formed at the large-diameter end. . The first mounting member 12 is mounted on the power unit side by a bolt (not shown) screwed into the screw hole 17 of the nut portion 15.
[0024]
Further, a main rubber elastic body 16 is vulcanized and bonded to the first mounting member 12. The main rubber elastic body 16 has a generally large truncated conical shape having a large diameter as a whole, which expands in a downward direction, and has an inverted mortar-shaped concave portion 18 which is open at the large-diameter end surface. The first mounting member 12 is arranged on the same central axis in a state of being inserted axially downward from the small diameter side end surface of the main rubber elastic body 16 and is vulcanized and bonded. A large-diameter cylindrical metal sleeve 20 is superposed on the outer peripheral surface of the large-diameter end portion of the main rubber elastic body 16 and is vulcanized and bonded.
[0025]
On the other hand, the second mounting member 14 has a large-diameter substantially stepped cylindrical shape, and has a large-diameter portion 26 at an upper portion in the axial direction with a step portion 24 formed at an intermediate portion in the axial direction interposed therebetween. At the same time, the lower part in the axial direction is a small diameter part 28. A thin seal rubber layer 30 covering almost the entire surface is provided on the inner peripheral surfaces of the large diameter portion 26 and the small diameter portion 28, respectively, and is vulcanized and bonded. A diaphragm 32 made of a thin rubber film having a substantially thin disk shape is provided, and the outer peripheral edge of the diaphragm 32 is vulcanized and bonded to the peripheral edge of the opening of the second mounting member 14, whereby the second The lower opening of the second mounting bracket 14 is fluid-tightly closed. In the present embodiment, the diaphragm 32 is formed integrally with the seal rubber layer 30, and the diaphragm 32 forms a flexible film.
[0026]
The large-diameter portion 26 of the second mounting member 14 is fixed to the outer peripheral surface of the main rubber elastic body 16 by being externally inserted into the metal sleeve 20 and fitted and fixed by press-fitting, drawing, or the like. ing. Thereby, the first mounting bracket 12 and the second mounting bracket 14 are arranged apart from each other so as to be located on substantially the same central axis which is the main input direction of the vibration to be damped. And are elastically connected by a rubber elastic body 16. Further, since the large-diameter portion 26 of the second mounting member 14 is fixed to the main rubber elastic body 16, the upper opening of the second mounting member 14 is closed in a fluid-tight manner by the main rubber elastic body 16. .
[0027]
Further, a bracket 31 is fixedly attached to the second mounting bracket 14 from above in the axial direction. The bracket 31 has a large diameter substantially cylindrical shape as a whole, and a plurality of legs 33 extending downward in the axial direction are welded to the outer peripheral surface. The bracket 31 is externally fitted and fixed to the large-diameter portion 26 of the second mounting bracket 14, and its leg 33 is bolted to a vehicle body (not shown) to thereby secure the second bracket 31. The mounting bracket 14 is fixedly mounted on the body.
[0028]
In the second mounting member 14, a partition member 34 is accommodated in the small diameter portion 28 thereof, and is disposed between the opposing surfaces of the main rubber elastic body 16 and the diaphragm 32. The partition member 34 is formed of a hard material such as a metal or a synthetic resin, and has a substantially thick disk-shaped block shape. The partition member 34 is fitted into the small-diameter portion 28 of the second mounting member 14, and its cylindrical outer peripheral surface is formed by press-fitting the small-diameter portion 28 or drawing the small-diameter portion 28. , Is tightly fixed to the small diameter portion 28 in a fluid-tight manner with a seal rubber layer 30 interposed therebetween. When the partition member 34 is assembled in the second mounting member 14 in this manner, a region formed between the main rubber elastic body 16 and the diaphragm 32 and sealed with respect to an external space is formed by the partition member 34. Thus, a main liquid chamber 36 in which a part of the wall portion is formed of the main rubber elastic body 16 is formed on the upper side of the partition member 34 while the main liquid chamber 36 is formed on the upper side of the partition member 34. On the lower side, an equilibrium chamber 38 is formed in which a part of the wall portion is constituted by the diaphragm 32 and a volume change is easily allowed based on the deformation of the diaphragm 32.
[0029]
The main liquid chamber 36 and the equilibrium chamber 38 are filled and sealed with incompressible fluids such as water, alkylene glycol, polyalkylene glycol, and silicone oil. In particular, in the present embodiment, a low-viscosity fluid having a viscosity of 0.1 Pa · s or less is preferably employed in order to advantageously obtain a vibration damping effect based on a resonance effect of the fluid described below. A lower recess 39 is formed at the lower end face in the axial direction of the partition member 34 and opens at the center portion. The volume of the equilibrium chamber 38 is advantageously secured by the lower recess 39. ing.
[0030]
The partition member 34 is formed with a substantially mortar-shaped central recess 40 that opens at the center of the upper surface, and protrudes upward from the partition member 34 at the periphery of the opening of the central recess 40. An annular locking projection 42 is integrally formed. A rubber elastic plate 44 as an elastic vibrating plate having a disk shape with a predetermined thickness is superposed on the opening of the central recess 40, and is vulcanized and bonded to the outer peripheral surface of the rubber elastic plate 44. A locking fitting 46 having a shape is externally fitted to the locking projection 42 of the partition member 34 at its lower end opening, and is caulked and fixed to the locking projection 42 in a fluid-tight manner. As a result, the opening of the central recess 40 is covered with the rubber elastic plate 44 in a fluid-tight manner, so that the working air chamber 50 independent of the main liquid chamber 36 and the equilibrium chamber 38 is formed. As will be described later, air pressure fluctuations are applied from an external air pressure source, and a vibration force is applied to the rubber elastic plate 44 based on the air pressure fluctuations in the working air chamber 50. .
[0031]
An air passage 78 is formed in the partition member 34 in order to cause pressure fluctuation to act on the working air chamber 50, and one open end of the air passage 78 communicates with the working air chamber 50. On the other hand, the other end of the air passage 78 is opened to a port 80 projecting from the outer peripheral surface of the partition member 34. In the mounted state, an external air line is connected to the port portion 80, so that air pressure fluctuations exerted by pressure control means (not shown) are transmitted from the air line to the working air chamber 50 through the air passage 78. Has been affected.
[0032]
Further, in the main liquid chamber 36 formed between the opposing surfaces of the main rubber elastic body 16 and the partition member 34, a partition member 52 as a partition having a substantially disk shape as a whole is housed and arranged. The partition member 52 has a structure in which upper and lower partition plates 54 and 56 each formed of a hard material such as metal or synthetic resin and each having a substantially disk shape are fixedly overlapped with each other. The mounting bracket 14 is provided so as to spread in a direction perpendicular to the axis. Then, the outer peripheral edge of the partition member 52 is sandwiched and held between the step portion 24 of the second mounting member 14 and the axial end surface of the main rubber elastic body 16 so that the partition member 52 is in the second position. It is fixed to the mounting bracket 14. Thus, the main liquid chamber 36 is fluid-tightly partitioned between the main rubber elastic body 16 and the partition member 34 with the partition member 52 interposed therebetween. Thus, a part of the wall is formed of the main rubber elastic body 16 between the main rubber elastic body 16 and the partition member 52, and the pressure change accompanying the elastic deformation of the main rubber elastic body 16 at the time of vibration input. While a pressure receiving chamber 58 to be generated is formed, a part of a wall portion is constituted by a rubber elastic plate 44 between the partition member 52 and the partition member 34, and the rubber elastic plate 44 serves as the working air chamber 50. A vibration chamber 60 is formed in which vibrations are generated based on the air pressure fluctuations, thereby directly causing pressure fluctuations.
[0033]
The partitioning member 34 has an outer peripheral groove 66 extending at a predetermined length in the circumferential direction at an intermediate portion in the axial direction, and the outer peripheral groove 66 is fluid-tight at the small diameter portion 28 of the second mounting member 14. A fluid flow path is formed by being covered by the cover. One end of the fluid flow path formed by the outer peripheral groove 66 is opened at the upper end surface of the partition member 34 on the outer peripheral side of the central recess 40 through a through hole 68 extending in the axial direction. . On the other hand, the other end of the outer circumferential groove 66 is opened to the lower recess 39 through a through hole (not shown) extending radially inward. Further, an annular groove 62 extending in the circumferential direction with a groove-shaped cross section opening upward is formed on the outer peripheral edge of the lower partition plate 56, and the annular groove 62 protruding downward is formed. The lower partition wall plate 56 is fluid-tightly fitted and fixed to the locking metal fitting 46 at the portion where the lower partition wall plate 56 is formed, and the annular groove 62 is covered with the upper partition wall plate 54 to form an annular flow path. ing. The annular flow path formed by the annular groove 62 is connected to the pressure receiving chamber 58 through a communication hole 70 formed through the upper partition plate 54 at one position facing the radial direction. Further, at the other position radially opposed to the annular flow path formed by the annular groove 62, the outer peripheral groove 66 of the partition member 34 is formed by a connection hole 72 penetrating through the lower partition plate 56. Connected to the fluid flow path.
[0034]
As a result, the annular flow path formed by the annular groove 62 and the fluid flow path formed by the outer peripheral concave groove 66 are connected in series with each other, so that the first pressure receiving chamber 58 and the equilibrium chamber 38 communicate with each other. An orifice passage 74 is formed. In addition, a second orifice passage 76 that connects the pressure receiving chamber 58 and the vibration chamber 60 to each other is formed by the annular flow path. That is, the second orifice passage 76 utilizes a part of the first orifice passage 74 by connecting the first orifice passage 74 to the vibration chamber 60 at an intermediate portion in the passage length direction. It is formed.
[0035]
Then, when a pressure fluctuation is generated in the pressure receiving chamber 58 based on the elastic deformation of the main rubber elastic body 16 at the time of vibration input, the pressure fluctuation is generated based on the relative pressure difference between the pressure receiving chamber 58 and the equilibrium chamber 38. Fluid flow between the two chambers 58 and 38 is generated through one orifice passage 74. In particular, in the present embodiment, the first orifice passage 74 is tuned to a low frequency range of about 10 Hz corresponding to an engine shake or the like. Thus, a passive vibration damping effect is exerted on the input vibration in the low frequency range based on the flow action such as the resonance action of the fluid that is caused to flow through the first orifice passage 74.
[0036]
In the present embodiment, the second orifice passage 76 is tuned to a middle frequency range of about 20 to 40 Hz corresponding to idling vibration or the like. Then, at the time of vibration input in the middle frequency range, the pressure fluctuation generated in the vibration chamber 60 based on the air pressure fluctuation of the working air chamber 50 is caused by the flow action such as the resonance action of the fluid caused to flow through the second orifice passage 76. , The pressure is effectively applied to the pressure receiving chamber 58, and the pressure fluctuation in the pressure receiving chamber 58 is positively adjusted, whereby an active vibration damping effect is exerted.
[0037]
The tuning of the first and second orifice passages 74 and 76 corresponds to, for example, the wall spring stiffness of the pressure receiving chamber 58, the equilibrium chamber 38, and the vibration chamber 60 (corresponding to the amount of pressure change required to change by a unit volume). This can be performed by adjusting the passage length and the passage cross-sectional area while taking into consideration the characteristic value of the passage, and generally, the phase of the pressure fluctuation transmitted through the orifice passages 74 and 76 changes, and the resonance state is substantially changed. Can be grasped as the tuning frequency of the orifice passages 74 and 76.
[0038]
Further, the upper and lower partition plates 54 and 56 constituting the partition member 52 are each formed with a large-diameter through-hole 82 at the center thereof, and a movable plate 84 is provided in the through-hole 82. The movable plate 84 is formed of a rigid metal plate and has a thin disk shape. On the other hand, the upper and lower partition plates 54 and 56 are separated from each other at the inner peripheral edge of the through-hole 82, so that a holding groove 86 that opens inward in the radial direction extends over the entire circumference in the circumferential direction. It is formed continuously. The outer peripheral edge of the movable plate 84 enters the holding groove 86 over the entire circumference, and is held with a predetermined play gap. Thus, the movable plate 84 is disposed so as to be movable in the axial direction by a predetermined distance until the movable plate 84 contacts both sides in the axial direction in the holding groove 86, that is, by the set play.
[0039]
Further, in the present embodiment, as shown in an enlarged view in FIG. 2, a rubber elastic body is vulcanized and bonded to the outer peripheral edge portion of the movable plate 84 that has entered the holding groove 86, and the entire periphery is vulcanized. An annular cushion rubber 88 is formed extending therethrough. In particular, the cushioning rubber 88 has a cross-sectional shape of an arc-shaped outer peripheral surface protruding radially outward and axially both sides from the outer peripheral edge of the movable plate 84, and extends over the entire circumferential direction of the movable plate 84. It is formed continuously.
[0040]
Further, the holding groove 86 for supporting the outer peripheral edge of the movable plate 84 has an inner peripheral surface shape having an arc-shaped cross section slightly larger than the outer peripheral surface of the buffer rubber 88 protruding from the movable plate 84. It is formed so as to extend over the entire circumference in the direction. As a result, as shown in FIG. 2, the movable plate 84 is positioned substantially at the center of the movement range in the holding groove 86, and between the outer peripheral edge of the movable plate 84 and the partition member 52. A third orifice passage extending between the outer peripheral surface of the cushion rubber 88 and the opposing surface of the inner peripheral surface of the holding groove 86 due to backlash to allow the pressure receiving chamber 58 and the vibration chamber 60 to communicate with each other. 90 are formed. Further, as shown in FIG. 3, the third orifice passage 90 allows the movable plate 84 to be displaced in any of the axial directions and the cushion rubber 88 to contact the inner peripheral surface of the holding groove 86. In this state, the through holes 82 formed in the upper and lower partition plates 54 and 56 are substantially fluid-tightly closed by the movable plate 84, so that they are substantially blocked and disappear. I have.
[0041]
In the present embodiment, the third orifice passage 90 is tuned to a high frequency range of about 50 to 200 Hz corresponding to the muffled sound and chatter vibration of the vehicle, and the third orifice passage 90 is externally applied to the working air chamber 50. When pressure fluctuations in a high frequency range are generated in the vibration chamber 60 based on the air pressure fluctuations generated, the vibration chamber 60 is controlled based on the flow action such as the resonance action of the fluid flowing through the third orifice passage 90. Is efficiently transmitted to the pressure receiving chamber 58.
[0042]
Therefore, in the engine mount 10 of the present embodiment having the above-described structure, when vibrations in a low frequency range such as an engine shake are input, the pressure receiving chamber 58 and the equilibrium chamber 60 are connected through the first orifice passage 74 as described above. An effective vibration damping effect can be exhibited by the high damping action based on the resonance action of the fluid flowing between them. In addition, at the time of vibration input in a medium frequency range such as idling vibration, or at the time of vibration input of a high frequency range such as running noise and chattering sound, the flow resistance of the fluid in the first orifice passage 74 increases remarkably anti-resonantly. It will be. Therefore, at the time of such a middle to high frequency vibration input, the rubber elastic plate 44 is vibrated by applying an external air pressure fluctuation to the working air chamber 50 in a cycle corresponding to the vibration to be damped. An internal pressure fluctuation is generated in the vibration chamber 60, and the internal pressure fluctuation in the vibration chamber 60 is applied to the pressure receiving chamber 58 through the second orifice passage 76 or the third orifice passage 90, so that the pressure fluctuation in the pressure receiving chamber 58 is activated. It is possible to control the target or aggressively, whereby a destructive or aggressive vibration damping effect is exerted.
[0043]
The external air pressure control means for exerting air pressure fluctuations on the working air chamber 50 is well known in the art and will not be described in detail here. For example, a negative pressure source such as a vacuum tank and the atmosphere are supplied to the working air chamber 50. An electromagnetic switching valve for connecting and selectively connecting the working air chamber 50 to the negative pressure source and the atmosphere on the connection pipe is provided, and the electromagnetic switching valve is controlled by a control signal corresponding to the vibration to be damped. This can be advantageously realized by performing the switching operation with. In addition, the control signal of the electromagnetic switching valve is generated, for example, by detecting an engine speed, an accelerator opening, a traveling speed, and the like with various sensors, and using an ignition signal of the engine as a reference signal, adaptive control, map control, and the like. The air pressure fluctuation having a cycle, a phase, and an amplitude corresponding to the vibration to be damped is taken into consideration so as to affect the working air chamber 50.
[0044]
Here, in the engine mount 10, the support plate 52 is supported by the partition member 52 that separates the pressure receiving chamber 58 and the vibration chamber 60, and is provided in the holding groove 86 of the movable plate 84 provided between the chambers 58 and 60. The second orifice passage 76 and the third orifice passage 90 are automatically switched according to the vibration frequency to be damped by appropriately adjusting the axial movement amount at I am being squeezed.
[0045]
Specifically, the vibration in the middle frequency range such as the idling vibration of about 20 to 40 Hz has a larger amplitude than the vibration in the high frequency range such as the running muffled sound of about 50 to 200 Hz. Therefore, when active control is performed in a medium frequency range such as idling vibration, an effective vibration damping effect is obtained, compared to when active control is performed in a high frequency range such as running muffled sound. Is set to be large, and as a result, a large amplitude pressure fluctuation is generated in the vibration chamber 60. On the other hand, when active control is performed in a high frequency range such as a running muffled sound, in order to obtain an effective anti-vibration effect, compared to a case where active control is performed in a middle frequency range such as idling vibration, the working air chamber 50 is not provided. The amplitude of the applied air pressure fluctuation is set to be small, and as a result, a pressure fluctuation of a small amplitude is generated in the vibration chamber 60.
[0046]
When the pressure fluctuation is generated in the vibration chamber 60 in this way, the relative pressure fluctuation between the vibration chamber 60 and the pressure receiving chamber 58 is exerted on the upper and lower surfaces of the movable plate 84, and the movable plate 84 is reciprocated in the axial direction. Here, the amount of displacement of the movable plate 84 in the axial direction is limited by the contact with the holding groove 86. In the present embodiment, the amount of displacement of the movable plate 84 in the axial direction is limited to a high frequency range. The pressure fluctuation generated in the vibration chamber 60 by the active control in the vibration chamber 60 is allowed to have a displacement amount that can be almost absorbed, while the pressure fluctuation generated in the vibration chamber 60 by the active control in the middle frequency range is allowed. The displacement is set so that the amount of displacement is limited so as not to completely absorb the pressure fluctuation.
[0047]
That is, for example, as shown in FIG. 4, it is necessary to absorb the pressure fluctuation caused in the vibration chamber 60 when performing active control for vibration damping in the middle frequency range (30 Hz). The axial displacement of the movable plate 84 is ± 0.4 mm, which is necessary to absorb pressure fluctuations caused in the vibration chamber 60 when performing active control for vibration damping in a high frequency range (100 Hz). Assuming that the axial displacement of the movable plate 84 is ± 0.06 mm, the allowable axial displacement (movable distance) of the movable plate 84 is set to, for example, ± 0.1 mm. Then, at the time of vibration input in the middle frequency range, when the air pressure fluctuation of the corresponding frequency is caused to cause the pressure fluctuation in the vibration chamber 60, the movable plate 84 moves to ± 0 with the pressure fluctuation of the vibration chamber 60. Although it is attempted to displace in the axial direction by 0.4 mm, it is actually limited to a range of ± 0.1 mm due to contact with the holding groove 86. As a result, for at least the remaining ± 0.3 mm, the pressure fluctuation is not absorbed by the displacement of the movable plate 84, and an effective pressure fluctuation is generated in the vibration chamber 60. Is applied to the pressure receiving chamber 58 through the second orifice passage 78 with an efficient pressure transmission efficiency utilizing the resonance action of the fluid, so that an effective vibration damping effect can be exhibited.
[0048]
In addition, in the active control in the middle frequency range, as is clear from FIG. 4, the movable plate 84 moves the holding plate 86 over a long period of time in one cycle (time t 'in FIG. 4). The through-hole 82 and thus the third orifice passage 90 are maintained in a closed state. Therefore, even if a higher-order component of the pressure fluctuation is induced in the vibration chamber 60, the transmission to the pressure receiving chamber 58 through the third orifice passage 90 can be effectively prevented, and the second Transmission to the pressure receiving chamber 58 through the orifice passage 76 can also be advantageously prevented by the anti-resonant action, and the deterioration of the vibration state caused by the higher-order component does not become a problem.
[0049]
On the other hand, at the time of vibration input in the high frequency range, when the air pressure fluctuation of the corresponding frequency is caused to cause the pressure fluctuation in the vibration chamber 60, the movable plate 84 has a high frequency of the pressure fluctuation applied. Due to the fact that the mass component (mass) itself acts on the flow resistance and mass of the sealed fluid additively, the displacement becomes difficult to follow the pressure fluctuation of the vibration chamber 60. Therefore, in a situation where active control is performed in a high frequency range, the movable plate 84 is held in a substantially stationary state or a state where it is slightly displaced slightly while floating from the holding groove 86. As a result, The third orifice passage 90 is maintained in communication between the movable plate 84 and the holding groove 86.
[0050]
Therefore, during active control in the high frequency range, the fluid flow resistance of the second orifice passage 76 significantly increases due to anti-resonant action and the like, but the third orifice passage 90 tuned to the high frequency range has Thus, the pressure fluctuation of the vibration chamber 60 is exerted on the pressure receiving chamber 58 with an efficient pressure transmission efficiency based on the flow action such as the resonance action of the fluid flowing through the third orifice passage 90. Thus, an effective anti-vibration effect can be exhibited.
[0051]
As described above, one embodiment of the present invention has been described in detail. However, this is merely an example, and the present invention is not interpreted in any limited manner by the specific description in the embodiment.
[0052]
For example, the amount of axial displacement allowed for the movable plate 84 by the play of the holding portion 86 due to the play of the gripping portion depends on the magnitude (amplitude) of the vibration to be damped, the volume of the vibration chamber 60, and the spring of the rubber elastic plate 44. It is appropriately set in consideration of the constant, the effective piston area, the volume of the working air chamber 50, and the like, and is not limited. Here, the movable displacement amount: δ allowed for the movable plate 84 is the theoretical maximum displacement amount (of the vibration chamber 60 due to the pressure fluctuation induced in the vibration chamber 60 at least in active control in the middle frequency range). Displacement to absorb pressure fluctuation): It is necessary to set smaller than δa, but it is not always necessary to set the theoretical maximum displacement due to pressure fluctuation induced in the vibration chamber 60 during active control in a high frequency range. Amount: need not be greater than δb. As described above, as described above, when the frequency of the applied pressure fluctuation increases, the movable plate 84 becomes difficult to be displaced by the action of the inertial force or the like, and the actual displacement becomes smaller than the theoretical maximum displacement. This is because it is held in the holding groove 86 in a floating state.
[0053]
The tuning frequency of each of the first orifice passage 74, the second orifice passage 76, and the third orifice passage 90 is appropriately set according to the required vibration isolation characteristics. It goes without saying that it is not limited.
[0054]
Furthermore, the specific structures of the first orifice passage 74, the second orifice passage 76, and the third orifice passage 90 are not limited at all, and the structure of the mount body and the mount size are taken into consideration. Then, it can be changed appropriately. In this case, for example, in the above-described embodiment, the second orifice passage 76 is formed by using a part of the first orifice passage 74. However, the first orifice passage 74 and the second orifice passage 76 are formed. May be formed with independent channel structures.
[0055]
For the purpose of tuning the third orifice passage 90, for example, a stenotic flow path is formed between the movable plate 84 and the pressure receiving chamber 58 in the partition member 52, and a fluid that allows the third orifice passage 90 to flow therethrough. However, it is also possible to guide the pressure to the pressure receiving chamber 58 through the narrowed flow path.
[0056]
In addition, in the above-described embodiment, a specific example in which the present invention is applied to an engine mount for an automobile has been described. However, the present invention also has an anti-vibration effect particularly against vibrations over a plurality of or a wide frequency range. Any of them can be effectively applied to a vibration isolator in various vibration members requiring the following.
[0057]
【The invention's effect】
As is clear from the above description, in the fluid filled type vibration damping device having the structure according to the present invention, the passive vibration damping effect by the first orifice passage is effectively exerted against the vibration in the low frequency range. On the other hand, for the vibration in the middle to high frequency range, the pressure fluctuation generated in the vibration chamber by applying air pressure fluctuation to the working air chamber at a cycle corresponding to the vibration to be damped is generated in the second orifice passage. By controlling the pressure in the pressure receiving chamber by exerting the pressure on the pressure receiving chamber through the third orifice passage, an active vibration damping effect can be exhibited.
[0058]
Also, in this case, the third orifice passage can be maintained in a substantially closed state during the vibration isolation operation of the medium-frequency vibration by making good use of the amplitude difference between the medium-frequency vibration and the high-frequency vibration. At the time of the vibration damping operation, the fluid flow through the second orifice passage is advantageously generated, and the transmission efficiency of the pressure fluctuation is improved based on the resonance action of the fluid caused to flow through the second orifice passage. And the transmission of higher-order components generated in the vibration chamber to the pressure receiving chamber can be effectively prevented, and the vibration-proof performance greatly reduced due to the transmission of such higher-order components. Can also be avoided.
[Brief description of the drawings]
FIG. 1 is an explanatory longitudinal sectional view showing an automobile engine mount as one embodiment of the present invention.
FIG. 2 is an explanatory view showing an enlarged main part of the engine mount shown in FIG. 1;
FIG. 3 is an explanatory view showing another operation state of the main part shown in FIG. 2;
FIG. 4 is a graph for explaining an operation of a movable plate in the engine mount shown in FIG. 1;
[Explanation of symbols]
10 Engine mount
12 First mounting bracket
14 Second mounting bracket
16 Rubber elastic body
32 diaphragm
38 Equilibrium chamber
44 Rubber elastic plate
50 working air chamber
52 Partition member
58 Pressure receiving chamber
60 Excitation chamber
74 First orifice passage
76 Second orifice passage
84 movable plate
86 Holding groove
88 cushion rubber
90 Third orifice passage

Claims (7)

A first mounting member and a second mounting member which are arranged apart from each other and are respectively mounted on members to be vibration-isolated and connected,
A body rubber elastic body that elastically connects the first mounting member and the second mounting member,
A pressure receiving chamber filled with an incompressible fluid, in which a part of a wall portion is formed of the main rubber elastic body and pressure fluctuation is generated at the time of vibration input,
An equilibrium chamber in which an incompressible fluid is sealed, in which a part of the wall is made of a flexible membrane and a volume change is allowed,
A first orifice passage communicating the pressure receiving chamber and the equilibrium chamber with each other,
A vibration chamber in which a part of a wall portion is formed of an elastic vibration plate and is filled with an incompressible fluid,
The vibrating force is applied to the elastic vibrating plate by applying air pressure fluctuation from the outside formed on the opposite side of the elastic vibrating plate with respect to the elastic vibrating plate. And a working air chamber that produces
A second orifice passage tuned to a higher frequency range than the first orifice passage and interconnecting the pressure receiving chamber and the vibration chamber;
A through hole is provided in the partition wall to form an annular holding groove that opens to the inner peripheral side at a peripheral portion of the through hole, and a hard movable plate is disposed in the through hole to form an outer peripheral portion of the movable plate. The movable plate can be displaced in the thickness direction by the amount of play in the holding groove by being inserted into the holding groove and gripped with a predetermined play. The through hole is substantially closed by contacting the inner surface of the groove, and the vibration chamber and the pressure receiving chamber communicate with each other by wrapping around the outer peripheral edge of the movable plate in the holding groove. A movable plate mechanism capable of forming a third orifice passage having a higher tuning frequency than the second orifice passage.
A fluid filled type vibration damping device characterized by having. A buffer rubber layer is provided on at least one of an inner surface of the holding groove formed in the partition and an outer peripheral edge of the movable plate which is brought into contact with the inner surface of the holding groove when the movable plate is displaced. The fluid filled type vibration damping device according to claim 1. The outer peripheral edge of the movable plate is formed so as to extend in the circumferential direction with an outer peripheral shape of a substantially arc-shaped cross section, and the holding groove is formed in an approximately arc-shaped cross section slightly larger than the outer peripheral surface of the movable plate. The third orifice passage is formed to have a substantially arc-shaped flow path between the outer peripheral surface of the movable plate and the inner peripheral surface of the holding groove by being formed so as to extend in the circumferential direction with the peripheral surface shape. The fluid filled type vibration damping device according to claim 1 or 2, wherein When air pressure fluctuations are applied to the working air chamber in the tuning frequency range of the second orifice passage to cause pressure fluctuations in the vibration chamber, the movable plate moves on the inner surface of the holding groove on both sides in the plate thickness direction. When the air pressure fluctuates in the working air chamber in the tuning frequency range of the third orifice passage to cause pressure fluctuation in the vibrating chamber, the movable plate The amplitude in the plate thickness direction is made smaller than the play of the movable plate with respect to the holding groove, and the contact of the movable plate with the holding groove in the plate thickness direction is suppressed. The fluid filled type vibration damping device according to any one of claims 1 to 3, wherein the orifice passage is formed substantially constantly. A connection window for connecting the first orifice passage to the vibrating chamber is formed in a longitudinally intermediate portion of the first orifice passage, so that a part of the first orifice passage is used. The fluid filled type vibration damping device according to any one of claims 1 to 4, wherein the second orifice passage is formed. By attaching one of the first attachment member and the second attachment member to the power unit side member and attaching the other to the body side member, an engine mount for supporting the power unit of the vehicle against vibration with respect to the body is constituted. The first orifice passage is tuned to a low frequency range corresponding to an engine shake, the second orifice passage is tuned to a medium frequency range corresponding to idling vibration, and the vehicle travels through the third orifice passage. The fluid filled type vibration damping device according to any one of claims 1 to 5, wherein the vibration is tuned to a high frequency range corresponding to a muffled sound. The second mounting member has a cylindrical shape, and the first mounting member is spaced apart from one opening side of the second mounting member, and the first mounting member and the second mounting member are separated from each other. By connecting with the main rubber elastic body, one opening of the second mounting member is covered in a fluid-tight manner, and the other opening in the axial direction of the second mounting member is fluidized by the flexible film. While the lid is tightly covered, the first partition member and the second partition member which are overlapped with each other in the axial direction of the second mounting member are fixedly supported by the second mounting member, and The pressure receiving chamber is formed between the partition member and the main rubber elastic body, and the equilibrium chamber is formed between the second partition member and the flexible membrane. The recess provided on the superposed surface side with respect to the first partition member is covered with the elastic vibration plate in a fluid-tight manner. 6. The fluid-filled vibration damping device according to claim 1, wherein the working air chamber is formed by the above and the vibration chamber is formed between the elastic vibration plate and the first partition member. .

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