JP2010031988A - Fluid-sealed vibration control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid-sealed vibration control device of a novel structure capable of exhibiting the effective vibration control effect particularly to large amplitude vibration of a high frequency area. <P>SOLUTION: While constituting a partition wall part of a pressure receiving chamber 124 and an intermediate chamber 128 out of a movable partition wall 62 for allowing elastic displacement, a partition wall part of the intermediate chamber 128 and a balancing chamber 126 is constituted of an elastic movable film 64. A movable plate 106 exerting pressure of the pressure receiving chamber 124 on one surface by restricting a displacement quantity and exerting pressure of the intermediate chamber 128 on the other surface, is arranged on the movable partition wall 62, and a dynamic damper is constituted for tuning a turning frequency of a second orifice passage 132 for communicating the intermediate chamber 128 with the balancing chamber 126 to a higher frequency area than a tuning frequency of a first orifice passage 130 for communicating the pressure receiving chamber 124 with the balancing chamber 126 and tuning a natural frequency of the movable partition wall 62 to a further higher frequency area than the second orifice passage 132. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an anti-vibration device used as, for example, an automobile engine mount, and more particularly, a fluid-filled vibration-proof device that obtains a vibration-proof effect by utilizing the flow action of an incompressible fluid sealed inside. It relates to the device.

  Conventionally, a fluid-filled vibration isolator has been known as a type of anti-vibration coupling body and anti-vibration support body mounted between members constituting a vibration transmission system. For example, application to an automobile engine mount is known. It is being considered. Such a fluid-filled vibration isolator is generally a pressure receiving chamber in which a first mounting member and a second mounting member are connected by a main rubber elastic body, and a part of the wall portion is configured by the main rubber elastic body. In addition, an equilibrium chamber in which a part of the wall portion is formed of a flexible film is provided, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber. The pressure receiving chamber and the equilibrium chamber are communicated with each other based on a relative pressure fluctuation caused between the pressure receiving chamber and the equilibrium chamber when vibration is input between the first mounting member and the second mounting member. The vibration isolating effect can be exhibited based on the resonance action of the fluid that can flow through the orifice passage formed as described above.

  By the way, in automobile engine mounts, high-frequency vibrations such as booming noise during driving and low-frequency vibrations such as engine shake tend to be a problem when the vehicle is running, while medium-frequency vibrations such as idling vibration are a problem when the vehicle is stopped. For example, a plurality of vibrations in different frequency ranges are input depending on the traveling state of the vehicle.

  However, in a fluid-filled vibration isolator equipped with an orifice passage, the orifice passage becomes substantially closed due to vibration at a frequency higher than the tuning frequency of the orifice passage, resulting in a significant increase in dynamic spring. Therefore, the vibration-proofing effect based on the resonance action of the fluid is difficult to be effectively exhibited only in a narrow frequency range in which the orifice passage is tuned.

  Therefore, for example, in Patent Document 1, a plurality of orifice passages tuned in different frequency ranges are provided, and the plurality of orifice passages are switched by an electromagnetic or negative pressure type actuator according to the frequency of input vibration. The structure to be made is proposed. However, the structure described in Patent Document 1 requires a special actuator and a control device for controlling the operation thereof, which increases the number of parts, makes the structure and control complicated, and increases the manufacturing cost. There was a problem.

  Further, for example, Patent Document 2 proposes a structure in which each vibration isolating device such as a plurality of orifice passages and movable plates is switched to function using the difference in amplitude of input vibration. However, in the structure as described in Patent Document 2, the switching operation of the vibration isolating device provided corresponding to each frequency is performed according to the amplitude of the input vibration. If it is set so as to function with respect to, it has been difficult to function with respect to high-frequency vibrations of large amplitude.

JP-A-2005-106150 JP 2007-51768 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is that it has a simple structure and is effective in preventing vibrations at a plurality of different frequencies. Vibration effect can be exhibited, and it is effective for large-amplitude vibrations in the high frequency range without deteriorating the vibration-proofing effect against vibrations in the low and medium frequency ranges. An object of the present invention is to provide a fluid-filled vibration isolator having a novel structure capable of exhibiting an effect.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, 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 an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  That is, the first aspect of the present invention includes a pressure receiving chamber in which a first mounting member and a second mounting member are connected by a main rubber elastic body, and a part of the wall portion is configured by the main rubber elastic body. The wall part forms an equilibrium chamber composed of a flexible membrane, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber communicate with each other. In the fluid-filled vibration isolator provided with the orifice passage, a partition member that partitions the pressure receiving chamber and the equilibrium chamber is supported by the second mounting member to form an intermediate chamber inside the partition member, and The partition portion of the partition member between the intermediate chamber and the pressure receiving chamber is constituted by a movable partition wall whose outer periphery is supported by a support rubber elastic body and is allowed to be elastically displaced. The partition with the chamber is composed of an elastic movable film, and further, displacement A restricted movable plate is provided in the movable partition wall so that the pressure of the pressure receiving chamber is exerted on one surface of the movable plate and the pressure of the intermediate chamber is exerted on the other surface. A second orifice passage communicating with the equilibrium chamber is provided, and the second orifice passage is tuned to a higher frequency region than the first orifice passage. The dynamic damper is configured by tuning the frequency to a higher frequency range than the second orifice passage.

  According to this aspect, when a low-frequency large-amplitude vibration such as an engine shake in which the first orifice passage is tuned is input, a relative pressure fluctuation is caused between the pressure receiving chamber and the equilibrium chamber. Thus, an anti-vibration effect (high damping effect) based on the resonance action of the fluid flowing through the first orifice passage is exhibited. In this case, the movable partition wall that is allowed to be elastically displaced is hardly displaced because its natural frequency is tuned to a higher frequency region that deviates from the tuning frequency of the first orifice passage. The pressure absorbing action of the pressure receiving chamber hardly occurs. In addition, when the large amplitude vibration is input, the displacement of the movable plate is limited, so that it cannot absorb the pressure fluctuation in the pressure receiving chamber. Thereby, a large pressure fluctuation is effectively induced in the pressure receiving chamber. As a result, the amount of fluid flow through the first orifice passage is sufficiently secured, and an effective anti-vibration effect against low-frequency large-amplitude vibration is exhibited.

  On the other hand, when the second orifice passage is tuned, for example, when an intermediate frequency medium amplitude vibration such as idling vibration is input, the first orifice passage is substantially clogged by the antiresonant action of the fluid. Pressure fluctuations act on the movable partition wall. In this case, the movable partition wall is hardly displaced because the natural frequency is tuned to a higher frequency region that is out of the tuning frequency of the second orifice passage. As a result, the pressure fluctuation in the pressure receiving chamber acts on the movable plate provided in the movable partition. Then, the effect of absorbing the pressure fluctuation of the pressure receiving chamber is exhibited based on the displacement within the allowable displacement amount of the movable plate, and the pressure fluctuation of the pressure receiving chamber is transmitted to the intermediate chamber. As a result, relative pressure fluctuations are induced between the intermediate chamber and the equilibrium chamber at the tuning frequency of the second orifice passage, and fluid flow through the second orifice passage is positively generated. As a result, an anti-vibration effect (low dynamic spring effect) based on the resonance action of the fluid flowing through the second orifice passage is exhibited.

  Furthermore, when a high frequency vibration such as a traveling boom noise is input in a frequency range higher than the tuning frequency of the second orifice passage, not only the first orifice passage but also the second orifice passage is anti-resonant. This causes a substantial clogging state. Therefore, particularly in this embodiment, since the dynamic damper configured to include the movable partition wall is tuned to the vibration frequency region that causes a problem in such a high frequency region, the movable partition wall is in a resonance state, and dynamic The vibration energy absorption effect due to the resonance action of the damper is exhibited, and the pressure fluctuation in the pressure receiving chamber is released to the equilibrium chamber through the elastic movable film constituting the partition between the intermediate chamber and the equilibrium chamber. As a result, the vibration damping effect of the dynamic damper and the pressure reducing effect of the pressure receiving chamber exhibit an effective vibration damping effect against high frequency vibration.

  Thus, according to this aspect, without using a special actuator or the like, it is possible to exhibit an effective vibration isolation effect against a plurality of vibrations ranging from a low frequency range to a high frequency range with a simple configuration. I can do it. In this aspect, since the anti-vibration effect against the high-frequency vibration is exhibited by utilizing the resonance action of the movable partition wall constituting the dynamic damper, the high-frequency vibration is prevented regardless of the magnitude of the amplitude. It is possible to exhibit an effective anti-vibration effect. In particular, according to this aspect, by providing the elastic movable film constituting the partition portion between the intermediate chamber and the equilibrium chamber, the first orifice passage and the second orifice passage are substantially clogged. Even so, the change in the volume of the intermediate chamber is allowed, so that the displacement amount of the movable partition is sufficiently secured, and the vibration damping effect of the dynamic damper can be more effectively exhibited.

  Furthermore, in this aspect, the movable partition wall provided with the movable plate is supported by the support rubber elastic body. As a result, even when a large amplitude vibration is input and a sudden pressure fluctuation occurs in the pressure receiving chamber, the abnormal noise generated due to the movable plate striking against the movable partition wall or the like is applied to the second mounting member. Transmission can be suppressed by an absorption action based on elastic deformation of the support rubber elastic body.

  Note that the movable plate in this aspect may be any plate that can be displaced substantially by the pressure action of the pressure receiving chamber. Alternatively, for example, the outer peripheral portion of the rubber film may be supported by a movable partition wall so that a minute displacement of the central portion is allowed based on elastic deformation of the rubber film itself.

  In this embodiment, the mass system and the spring system of the sub-vibration system (dynamic damper) configured to include the movable partition are not composed of only the movable partition and the supporting rubber elastic body supporting the movable partition. . That is, as the mass component in the secondary vibration system, it is necessary to consider not only the mass of the movable partition wall, but also the fluid mass between the movable partition wall and the elastic movable film, while the spring component includes the support rubber elastic body. In addition to the spring component, it is necessary to consider the spring component of the elastic movable film, the spring component of the pressure receiving chamber and the equilibrium chamber (expansion spring component), and the like. Accordingly, the natural frequency of the movable partition wall is not sufficient to tune the movable partition wall and the supporting rubber elastic body by taking them alone into the atmosphere. For example, when the fluid-filled vibration isolator according to this embodiment is used as an engine mount Therefore, it should be tuned so that the target natural frequency is exhibited in the mounting state of the mount.

  According to a second aspect of the present invention, in the fluid-filled vibration isolator according to the first aspect, a communication hole that connects the pressure receiving chamber and the intermediate chamber is formed in the movable partition wall, and the communication hole is closed. And a biasing means for exerting a biasing force in the closing direction on the valve body so that the closed state is maintained against the positive pressure action from the pressure receiving chamber side. Further, the negative pressure action from the pressure receiving chamber is characterized in that the valve body is allowed to operate in the opening direction against an urging force.

  In a conventional fluid-filled vibration isolator, when a large vibration load is input between the first mounting member and the second mounting member, abnormal vibration or vibration may be generated from the vibration isolator. . The generation of such abnormal noise and vibration is considered to be caused by bubbles that can be understood as cavitation. In other words, when shock vibration is input, the fluid flow between the pressure receiving chamber and the equilibrium chamber through the orifice passage cannot follow, and an excessive negative pressure is instantaneously generated in the pressure receiving chamber. Gas is separated from the fluid to form bubbles that can be interpreted as cavitation. When these bubbles collapse, they deform and form explosive micro jets (micro jets), which become water hammer pressure and propagate to the first mounting member and the second mounting member, It is thought that vibration occurs.

  With respect to such a problem, according to this aspect, the valve body is configured as a one-way valve. In such a one-way valve, the urging force of the urging means is set so that it does not open unless the negative pressure in the pressure receiving chamber exceeds a predetermined value, and a large negative pressure has been generated so that cavitation occurs in the pressure receiving chamber. Only in this case, the valve body is opened based on the relative pressure difference between the pressure receiving chamber and the intermediate chamber. As a result, when an excessive negative pressure is generated in the pressure receiving chamber, the pressure receiving chamber and the intermediate chamber are communicated with each other through the communication hole of the movable partition wall, and the excessive negative pressure in the pressure receiving chamber is quickly caused by the fluid inflow from the intermediate chamber. Can be resolved. As a result, the occurrence of cavitation is suppressed, and the generation of abnormal noise and vibration that can be attributed to this is effectively suppressed.

  On the other hand, when the positive pressure is generated in the pressure receiving chamber, or the pressure fluctuation caused by the vibration input to the extent that the operation of the orifice passage and the operation of the dynamic damper are expressed, the closed state of the communication hole by the valve body is maintained. . Accordingly, it is possible to suppress the generation of abnormal noise and vibration that may be caused by cavitation while effectively ensuring the dynamic damper effect due to the fluid flow amount through the orifice passage and the displacement of the movable partition wall.

  In this case, the biasing means is set with a large biasing force that allows the valve body to open only when an excessive negative pressure is generated in the pressure receiving chamber. Therefore, when the valve body is closed, the valve body may strongly hit against the closed portion of the movable partition wall with a large urging force, and there is a risk that a loud sound is generated. However, according to this aspect, since the movable partition wall is supported by the support rubber elastic body, the support rubber can transmit the hitting sound generated due to the valve body striking strongly to the second mounting member. It can absorb based on the elastic deformation of the elastic body, and an excellent sound reduction effect can be obtained.

  In addition, as an urging means in this aspect, various things, such as a metal spring, a resin spring, a rubber spring, can be employ | adopted suitably, For example, As said 3rd aspect of this invention, said 2nd In the fluid-filled type prevention device according to the aspect, an aspect in which the urging means that exerts an urging force on the valve body is configured using a metal coil spring may be employed.

  In this way, even if the coil spring is slightly bent or twisted because the seat surface of the coil spring is slightly inclined, the coil spring is approximately uniform in the circumferential direction of the coil spring. Can exert a biasing force. As a result, the closed state of the communication hole can be maintained more stably, and fluid leakage can be more effectively suppressed. Furthermore, since the spring characteristics of the coil spring can be easily and stably adjusted by adjusting the stroke length, the urging force exerted on the valve body can be adjusted and set easily and accurately. Moreover, durability excellent in repeated expansion and contraction accompanying opening and closing of the valve body can be obtained. Further, since there is no damping such as rubber or the like, a quicker opening / closing operation of the valve body can be realized.

  Note that the valve body can be disposed, for example, in a storage area formed in the movable partition wall. In such a case, the metal coil spring gradually contracts toward the valve body. An embodiment having a tapered taper shape is more preferably employed. That is, it is preferable that the position of the urging force exerted on the valve body by the coil spring is set at the approximate center of the communication hole closed by the valve body in order to stably maintain the closed state by the valve body. This is because if the position of the coil spring acting on the valve body is at a position away from the communication hole, a sufficient urging force may not be obtained.

  Therefore, the pressing position of the coil spring to the valve body, that is, the diameter of the end of the coil spring on the valve body side is set smaller than the outer diameter of the valve body by a predetermined dimension. On the other hand, the storage area for storing the valve body is naturally formed larger than the outer diameter of the valve body. Therefore, when the coil spring has a constant diameter, the diameter of the end opposite to the valve body is smaller than the inner peripheral surface of the receiving area with which the end abuts, and the coil spring contact position However, it is a position spaced inward from the peripheral wall rising from the inner peripheral surface. If it does so, it will become easy to shift in position in the diameter direction of a coil spring, the press position with respect to a valve body will change carelessly, and there is a problem that the press position of a coil spring will deviate from the target position to a communicating hole. . In order to solve this problem, it is also conceivable to form a locking projection on the inner peripheral surface of the accommodation area where the coil spring is brought into contact, and to lock and position the coil spring with the locking projection. However, in this case, the coil spring must be assembled while being positioned with respect to the locking projection, which not only increases the number of assembly steps, but also makes it difficult to return the coil spring from the locking projection. However, it is not always preferable.

  Therefore, by adopting a coil spring having a taper shape, and adjusting the coil diameter on the large diameter side to the size of the inner peripheral surface of the accommodation area where the end on the large diameter side is brought into contact, the inner peripheral surface The end on the large diameter side can be positioned stably and easily in the radial direction by using the peripheral wall rising from the center. If the coil diameter on the small diameter side is set according to the position of the communication hole by such positioning, the urging force of the coil spring can be stably applied to the portion where the communication hole is positioned.

  According to a fourth aspect of the present invention, in the fluid-filled vibration isolator according to the second or third aspect, the valve body is formed of a rubber elastic body, and the pressure receiving chamber side opening in the communication hole It is characterized by being superimposed from the part side.

  According to this aspect, since the valve body is formed of the rubber elastic body, it is possible to further reduce the contact sound when the valve body hits the closed portion of the movable partition wall. Moreover, the sealing performance in the closed state of the communication hole can be further improved. Furthermore, the valve body is overlapped from the opening side on the pressure receiving chamber side in the communication hole, so that the biasing direction of the valve body by the biasing means and the direction in which the positive pressure of the pressure receiving chamber is exerted on the valve body are made substantially equal. The closed state of the communication hole can be maintained more stably. In this embodiment, the pressure-receiving chamber side opening side of the communication hole does not mean only the opening end of the communication hole to the pressure-receiving chamber. For example, a space for disposing the valve body in the intermediate portion of the communication hole. It may be provided so that the valve body is overlapped from the opening side on the pressure receiving chamber side to the intermediate portion.

  According to a fifth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to fourth aspects, the second attachment member includes a cylindrical portion, and the cylindrical shape While the first mounting member is spaced apart on one side in the axial direction of the part, the partition member is provided with a cylindrical fixing part that is fitted and fixed to the cylindrical part, The movable partition and the elastic movable film are supported on the cylindrical fixing portion.

  According to this aspect, since the movable partition and the elastic movable film are supported on the cylindrical fixing portion, the movable partition and the elastic movable film are easily disposed in the partition portions of the intermediate chamber, the pressure receiving chamber, and the equilibrium chamber. And can be easily assembled to the second mounting member.

  According to a sixth aspect of the present invention, in the fluid-filled vibration isolator according to the fifth aspect, the movable partition is connected to the cylindrical fixing portion of the partition member via the support rubber elastic body. In addition, a covering rubber layer is formed on the inner peripheral surface of the cylindrical portion of the second mounting member, and the cylindrical fixing portion is attached to the cylindrical portion via the covering rubber layer. It is characterized by being elastically fitted and supported.

  According to this aspect, when large-amplitude vibration is input, transmission of abnormal noise or vibration generated due to the movable plate or the valve body striking against the movable partition wall to the cylindrical fixing portion is supported. It can be reduced by the absorption action based on the elastic deformation of the elastic body, and the transmission of such abnormal noise and vibration from the cylindrical fixing portion to the second mounting member is reduced by the absorption action based on the elastic deformation of the covering rubber layer. I can do it. That is, noise and vibration generated in the movable partition wall can be doubled by the support rubber elastic body and the covering rubber layer, and further silence and vibration reduction effect can be obtained. For example, the present invention is particularly preferably applied to an automobile engine mount. The first mounting member is fixed to the power unit, and the second mounting member is fixed to the vehicle body. Anti-vibration support. Under such a mounting state, the vibration energy accompanying the impact of the movable plate or the valve body against the movable partition wall when the impact load is input is absorbed by the supporting rubber elastic body and the covering rubber layer, and the second mounting is performed. Transmission to the member is reduced. As a result, vibration energy transmitted from the second mounting member to the vehicle body is suppressed, and vibrations and abnormal noises felt by passengers in the vehicle cabin are effectively reduced.

  Further, according to this aspect, the movable partition wall is elastically supported by the cylindrical fixing portion of the partition member via the support rubber elastic body, and the partition member is attached to the second mounting member via the covering rubber layer. Elastically supported. Thereby, a two-degree-of-freedom system in series of a first dynamic damper configured to include a movable partition wall and a supporting rubber elastic body, and a second dynamic damper configured to include a partition member and a covering rubber layer is provided. A vibration model can be realized. Therefore, by appropriately adjusting the mass and spring constant of the second dynamic damper and using the damping effect, the damping effect can be reduced compared to the case where only the first dynamic damper is used. The degree of freedom in tuning is increased, and it becomes easier to meet the demands for higher vibration isolation characteristics.

  The mass system and the spring system of the secondary vibration system (the second dynamic damper) configured including the partition member and the covering rubber layer are also included in the secondary vibration system (the first dynamic system described above) including the movable partition wall. Like the mass system and the spring system of one dynamic damper, it is not composed of only the partition member and the coating rubber layer alone. In other words, the natural frequency of the partition member exhibits the target natural frequency when mounted on the mount, taking into account the fluid mass of the intermediate chamber, the spring component (expansion spring component) of the pressure receiving chamber, the equilibrium chamber, etc. Tuned to be.

  A seventh aspect of the present invention is the fluid-filled vibration isolator according to the sixth aspect, wherein the fluid-tight vibration isolator is connected to the outer peripheral portion of the flexible film and is fitted to the cylindrical portion of the second mounting bracket. An axial contact rubber is interposed between the annular fixing bracket to be fixed and the cylindrical fixing portion of the partition member, and a step portion formed in the axial contact rubber and the main rubber elastic body. The cylindrical fixing portion is elastically supported in the axial direction between the two.

  According to this aspect, it is possible to adjust the elastic support characteristics of the partition member by adjusting the member elasticity, shape, size, and the like of the axial contact rubber, and the reliability and durability of the liquid seal are highly enhanced. While ensuring, the freedom degree of adjustment of the elastic support characteristic of a partition member can be enlarged more. In addition, since an axial contact rubber is interposed between the partition member and the annular fixing bracket, abnormal noise or vibration generated in the partition member due to the movable plate or the valve body striking against the movable partition wall. Transmission to the annular fixing bracket can be reduced by the axial contact rubber, and transmission of such abnormal noise and vibration to the second mounting member via the annular fixing bracket can be reduced.

  The axial contact rubber may be formed as a single body, but is preferably formed integrally with at least one of the main rubber elastic body and the flexible film. In this way, the number of parts can be reduced, and the number of assembly steps can be reduced.

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

  First, FIG. 1 shows an automotive engine mount 10 as a first embodiment of a fluid-filled vibration isolator having a structure according to the present invention. The engine mount 10 has a structure in which a first mounting bracket 12 as a first mounting member and a second mounting bracket 14 as a second mounting member are elastically connected by a main rubber elastic body 16. One mounting bracket 12 is attached to a power unit (not shown) that is one member constituting the vibration transmission system, and the second mounting bracket 14 is attached to a vehicle body (not shown) that is the other member constituting the vibration transmission system. As a result, the power unit is connected to the vehicle body in a vibration-proof manner. In the following description, the up and down direction refers to the up and down direction in FIG. 1 which is the main vibration input direction.

  More specifically, the first mounting bracket 12 is made of a metal material such as iron or aluminum alloy, and has a substantially cylindrical threaded portion 18 and a substantially cut portion integrally formed below the threaded portion 18. And a fixed part 20 having a truncated cone shape. Further, a stopper portion 22 that protrudes radially outward is integrally formed at the connection portion between the screwed portion 18 and the fixing portion 20. The screw portion 18 is formed with a bolt hole 24 that linearly extends on the central axis and opens at the upper end surface. A member on the power unit side (not shown) is screwed into the bolt hole 24 via a fixing bolt. By being fixed, the first mounting bracket 12 is attached to the power unit.

  On the other hand, the second mounting bracket 14 is formed of the same metal material as that of the first mounting bracket 12 and includes a cylindrical portion 26 having a thin, large-diameter, generally cylindrical shape. A tapered portion 28 that gradually increases in diameter as it goes upward in the axial direction is formed at the upper end portion in the axial direction of the cylindrical portion 26, and the upper end edge of the tapered portion 28 is outside the direction perpendicular to the axial direction. A flange-shaped portion 30 that extends toward the direction is integrally formed. Further, a caulking portion 32 extending downward in the axial direction is integrally formed at the lower end portion in the axial direction of the second mounting member 14. The second mounting bracket 14 is attached to a vehicle body side member via a bracket member or the like (not shown).

  The first mounting bracket 12 and the second mounting bracket 14 are disposed on the substantially same central axis as the second mounting bracket 14 and spaced apart upward in the axial direction. A main rubber elastic body 16 is interposed between the two. The main rubber elastic body 16 is formed of a rubber elastic body having a thick, large-diameter, generally frustoconical shape, and has an inverted mortar shape or hemispherical shape at its large-diameter side end. A large-diameter recess 34 that opens toward the top is formed. The small-diameter side end portion of the main rubber elastic body 16 is overlapped and vulcanized and bonded to the fixing portion 20 of the first mounting bracket 12, and the large-diameter side end portion of the main rubber elastic body 16. The outer peripheral surface is superimposed on the inner peripheral surface of the tapered portion 28 of the second mounting bracket 14 and the flange-shaped portion 30 and vulcanized and bonded. As a result, the first mounting bracket 12 and the second mounting bracket 14 are elastically connected to each other by the main rubber elastic body 16, and the axially upper opening of the second mounting metal 14 is the main rubber elastic body. In the present embodiment, the main rubber elastic body 16 is formed as an integrally vulcanized molded product integrally provided with the first mounting bracket 12 and the second mounting bracket 14. ing.

  A stopper rubber 36 is formed on the outer peripheral edge of the stopper portion 22 of the first mounting member 12 and is formed by the main rubber elastic body 16 being turned upward. Further, on the inner peripheral surface of the cylindrical portion 26 of the second mounting bracket 14, a thin wall as a covering rubber layer integrally formed with the main rubber elastic body 16 and extending downward from the opening edge of the large-diameter recess 34. The sealing rubber layer 38 is deposited. Furthermore, a stepped portion 40 that extends in the direction perpendicular to the axis is formed at the axially intermediate portion of the seal rubber layer 38, and the axially lower portion across the stepped portion 40 is thinner than the axially upward portion.

  Further, a diaphragm 42 as a flexible film is attached to the integrally vulcanized molded product of the main rubber elastic body 16. The diaphragm 42 is formed of a thin rubber elastic body having a substantially disk shape. The diaphragm 42 has a sufficient slack in the axial direction at the outer peripheral portion, and the central portion in the radial direction is convex upward. It has a generally dome shape. An abutting protrusion 44 that protrudes upward is integrally formed at the radial center portion of the diaphragm 42. Further, an annular fixing portion 46 is integrally formed on the outer peripheral edge of the diaphragm 42, and a large-diameter ring-shaped fixing bracket 48 as an annular fixing bracket is superimposed on the outer peripheral surface of the annular fixing portion 46 and vulcanized. It is glued. Thereby, in this embodiment, the diaphragm 42 is formed as an integrally vulcanized molded product provided with the fixing bracket 48.

  The diaphragm 42 is fixed to the second mounting bracket 14 by the fixing bracket 48 being inserted into the lower end opening of the second mounting bracket 14 and being fixed to the caulking portion 32. As a result, the opening in the axially lower direction of the second mounting bracket 14 is covered fluid-tightly by the diaphragm 42, and the main rubber elastic body 16 and the diaphragm 42 that cover both sides in the axial direction of the second mounting bracket 14 are covered. A fluid chamber 50 in which an incompressible fluid is sealed is formed between the axially opposed surfaces.

  The incompressible fluid sealed in the fluid chamber 50 is not particularly limited, but water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixed solution thereof are all suitably employed. obtain. Further, in order to advantageously obtain a vibration isolation effect based on the fluid flow action described later, it is desirable to employ a low viscosity fluid having a viscosity of 0.1 Pa · s or less as the sealed fluid.

  Furthermore, the partition member 52 is accommodated in the fluid chamber 50 so as to spread in the direction perpendicular to the axis. The partition member 52 is provided with a movable partition wall 62 supported by a support rubber elastic body 60 in an upper opening of a partition member main body 58 as a cylindrical fixing portion having a substantially cylindrical shape, and elastic in a lower opening. A movable rubber film 64 as a movable film is provided.

  The partition member main body 58 is made of, for example, a metal such as iron or aluminum alloy, or a hard synthetic resin, and has a substantially cylindrical shape that opens on both the upper and lower sides in the axial direction. An upper step portion 66 protruding radially inward is formed at a substantially intermediate portion in the axial direction on the inner peripheral surface of the partition member main body 58, and an inner diameter below the upper step portion 66 is made smaller. A lower stepped portion 68 protruding radially inward is formed below the upper stepped portion 66, and the inner diameter below the lower stepped portion 68 is further reduced.

  Further, the first circumferential groove 70 and the second circumferential groove open to the outer circumferential surface of the partition member main body 58 and extend in the circumferential direction with a length of a little less than one round in the axially upper and lower portions of the outer peripheral portion of the partition member main body 58. The circumferential grooves 72 are respectively formed. The first circumferential groove 70 and the second circumferential groove 72 are communicated with each other through a connection hole 74 formed in the axial direction of the partition member main body 58 at one end in the circumferential direction thereof. In 58, the first circumferential groove 70 and the second circumferential groove 72 form a circumferential groove having an outer peripheral surface extending in the circumferential direction with a length of slightly less than two rounds. In addition, a first through hole 76 that opens above the partition member main body 58 is formed at the circumferential end on the opposite side of the connection hole 74 in the first circumferential groove 70, while the second circumferential groove 72, a second through hole 78 that opens below the partition member main body 58 is formed at the circumferential end opposite to the connection hole 74. Furthermore, a third through hole 80 that opens to the inner peripheral surface of the partition member main body 58 is formed in a part of the second circumferential groove 72 in the circumferential direction.

  The movable partition wall 62 includes a partition wall body 82 and a lid member 84. As shown in FIG. 2, the partition wall main body 82 is made of, for example, a metal such as iron or aluminum alloy, or a hard synthetic resin, and has a substantially bottomed cylindrical shape as a whole opening upward. Further, a cylindrical partition wall portion 88 protruding upward from the bottom wall portion 86 is integrally formed on the partition wall body 82 on a concentric shaft. A plurality of first lower communication holes 90 are provided in the thickness direction inward of the bottom wall portion 86 in the radial direction from the partition wall portion 88, and in the radial direction from the partition wall portion 88. A plurality of second lower communication holes 92 are provided outside. Although not necessarily obvious from the drawings, in the present embodiment, the first lower communication hole 90 is concentrically with the bottom wall portion 86 and has a predetermined radial width dimension slightly less than ¼ circumference. It has a substantially arc shape extending over a small circumferential dimension, and four first lower communication holes 90 are formed on the concentric circle of the bottom wall portion 86 at a predetermined interval in the circumferential direction. As a result, the first lower communication hole 90 can be closed substantially uniformly in the circumferential direction by the annular rubber plate 102 described later.

  On the other hand, the lid member 84 is formed of a member similar to the partition wall main body 82 and has a substantially disk shape having an outer diameter dimension equal to the outer diameter dimension of the partition wall main body 82. A circular first upper communication hole 94 is formed through the central portion of the lid member 84, while a plurality of second upper communication holes 96 are provided radially outward of the first upper communication hole 94. It is penetrating. The diameter of the first upper communication hole 94 is smaller than the inner diameter of the partition wall portion 88 of the partition wall body 82.

  The lid member 84 is assembled so as to overlap the upper opening end surface of the partition wall main body 82. Although detailed illustration is omitted, for example, the lid member 84 is assembled to the partition wall main body 82 by, for example, protruding a caulking portion protruding upward from the partition wall main body 82 through the cover member 84 and projecting upward. This is performed by caulking the caulking portion protruding from the lid member 84. As a result, the opening of the partition wall main body 82 is covered with the lid member 84, and the internal space of the partition wall main body 82 is partitioned by the partition wall portion 88, and inside the movable partition wall 62, inside the partition wall portion 88. Is formed with a substantially cylindrical first accommodation cavity 98 extending in the vertical direction with a substantially constant inner diameter dimension, while surrounding the first accommodation cavity 98 around the partition wall portion 88. A tunnel-like second accommodation space 100 extending in the direction is formed.

  In the first accommodation space 98, an annular rubber plate 102 as a valve body and a coil spring 104 as an urging means for exerting an urging force on the annular rubber plate 102 are accommodated and disposed. The annular rubber plate 102 is formed of a rubber elastic body and has a circular plate shape having a predetermined thickness and a through hole at the center. Further, the outer diameter of the annular rubber plate 102 is made larger than the outer diameter of the annular shape formed by the plurality of first lower communication holes 90 extending in an arc shape with a predetermined radial width. At the same time, the inner diameter of the annular rubber plate 102 is made smaller than the inner diameter of the annular shape formed by the plurality of first lower communication holes 90. In short, the annular rubber plate 102 is formed with a size that can cover the entire opening of the plurality of first lower communication holes 90 into the first accommodation space 98.

  On the other hand, the coil spring 104 is preferably made of metal. As the coil spring 104, a coil spring having a certain diameter dimension and extending straight in the axial direction can also be used. In particular, in the present embodiment, the coil spring 104 has a tapered shape that gradually decreases in diameter in the axial direction. Is adopted. Here, the diameter dimension of the end portion on the large diameter side of the coil spring 104 is slightly smaller than the inner diameter dimension of the first accommodation space 98. On the other hand, the diameter dimension of the end portion on the small diameter side of the coil spring 104 is larger than the inner diameter dimension of the annular rubber plate 102 and smaller than the outer diameter dimension. The inner diameter dimension of the annular shape formed by the communication hole 90 is larger and smaller than the outer diameter dimension.

  Then, while the end portion on the large diameter side of the coil spring 104 is overlapped with the lid member 84, the end portion on the small diameter side is overlapped with the annular rubber plate 102, and the annular rubber plate 102 and the coil spring 104 are first. Thus, the coil spring 104 is compressed between the annular rubber plate 102 and the lid member 84 in the axial direction. As a result, a downward biasing force is exerted on the annular rubber plate 102 by the restoring force of the coil spring 104, and the annular rubber plate 102 is pressed against the bottom wall portion 86 of the partition wall body 82 from above, and the bottom wall portion A first lower communication hole 90 penetrating through 86 is closed from above by an annular rubber plate 102. In particular, in the present embodiment, the end portion on the large diameter side of the coil spring 104 is positioned in the radial direction by the partition wall portion 88, thereby pressing the annular rubber plate 102 at the end portion on the small diameter side of the coil spring 104. Is positioned above the center portion of the first lower communication hole 90.

  The urging force exerted on the annular rubber plate 102 by the coil spring 104 is a vibration that causes the operation of the first orifice passage 130 and the second orifice passage 132 described later and the dynamic damper operation by the movable partition wall 62. The annular rubber plate 102 is not separated from the bottom wall portion 86 due to pressure fluctuations due to input, and the annular rubber plate 102 is only in the bottom wall portion when an excessive negative pressure is generated to the extent that cavitation occurs in the pressure receiving chamber 124 described later. It is preferable that the distance is set so as to be separated from 86.

  On the other hand, a movable rubber plate 106 as a movable plate is accommodated in the second accommodation space 100. The movable rubber plate 106 has a substantially annular plate shape formed of a rubber elastic body, and an inner peripheral elastic protrusion 108 protruding in the axial direction is integrally formed at an inner peripheral end edge thereof. On the other hand, the outer peripheral end edge is integrally formed with an outer peripheral elastic protrusion 110 that protrudes on both sides in the axial direction. The inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110 are ridges extending in the circumferential direction with a substantially constant cross-sectional shape, and the protruding tip portion has a substantially semicircular cross-sectional shape. .

  Such a movable rubber plate 106 is accommodated and disposed in the second accommodating space 100 so as to be extrapolated with a slight gap with respect to the partition wall portion 88 of the partition wall main body 82. It should be noted that the inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110 of the movable rubber plate 106 are brought into contact with the lid member 84 and the bottom wall portion 86 of the partition wall main body 82 under such an accommodation arrangement. The inner peripheral elastic protrusions 108 and the outer peripheral elastic protrusions 110 are elastically deformed in the axial direction, so that the movable rubber plate 106 is allowed to be slightly displaced in the axial direction, and the inner peripheral elastic protrusions. Based on the elasticity of 108 and the outer peripheral elastic projection 110, the displacement of the movable rubber plate 106 is buffered. The second upper communication hole 96 and the second lower communication hole 92 are positioned on both the upper and lower sides of the movable rubber plate 106, respectively. Thus, the second upper communication hole 96 and the second lower communication hole 92 are positioned between the inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110 of the movable rubber plate 106, and the movable rubber plate 106. It is designed to be sealed with.

  A cylindrical metal sleeve 112 is disposed on the concentric shaft at a predetermined distance on the outer side in the radial direction of the movable partition wall 62 having such a structure, and between the movable partition wall 62 and the metal sleeve 112. Further, a support rubber elastic body 60 is interposed. The support rubber elastic body 60 has a thick annular plate shape as a whole, and its inner peripheral surface is vulcanized and bonded to the outer peripheral surface of the partition wall main body 82, and its outer peripheral surface is the inner surface of the metal sleeve 112. It is vulcanized and bonded to the peripheral surface. Thus, the support rubber elastic body 60 is formed as an integrally vulcanized molded product including the metal sleeve 112 and the partition wall body 82.

  Then, the metal sleeve 112 is inserted from the upper opening of the partition member main body 58 and is press-fitted and fixed in a state of being superimposed on the upper stepped portion 66 of the partition member main body 58, whereby the support rubber elastic body 60 is integrally vulcanized. The product is assembled to the partition member main body 58. As a result, the movable partition wall 62 and the partition member main body 58 are connected by the support rubber elastic body 60, and the upper opening of the partition member main body 58 is covered with the support rubber elastic body 60 and the movable partition wall 62. The movable partition wall 62 is elastically supported by the support rubber elastic body 60 with respect to the partition member main body 58 in a state in which the movable partition wall 62 can be displaced in the vertical direction.

  On the other hand, a movable rubber film 64 is disposed in the lower opening of the partition member main body 58. The movable rubber film 64 has a substantially disc shape formed from a rubber elastic body. An outer peripheral fixing portion 114 having a substantially circular cross section that slightly protrudes on both sides in the thickness direction of the movable rubber film 64 and extending over the entire circumferential direction is integrally formed at the outer peripheral edge of the movable rubber film 64. Further, a thick portion 116 that is substantially circular and slightly protrudes on both sides in the thickness direction is integrally formed at the central portion of the movable rubber film 64.

  Such a movable rubber film 64 is nipped and fixed between the partition member main body 58 and the lower lid member 118 at the lower end portion of the partition member main body 58. Specifically, a substantially circular concave fitting recess 120 that is opened downward with a diameter larger than the inner diameter of the lower stepped portion 68 is formed at the center of the lower end surface of the partition member main body 58. Yes. On the other hand, the lower lid member 118 is formed of a member similar to the partition member main body 58 and has a substantially annular plate shape having an inner diameter dimension substantially equal to the lower stepped portion 68 of the partition member 58. Here, a support concave portion 122 is formed on the upper end surface of the lower lid member 118 so as to open upward with a substantially circular concave shape. The outer peripheral portion of the support concave portion 122 is a partition member main body 58 of the lower lid member 118. In the overlapped state, a space having a substantially circular cross-sectional shape slightly smaller than the outer peripheral fixed portion 114 of the movable rubber film 64 is formed in cooperation with the fitting recess 120. Then, the movable rubber film 64 is fitted into the fitting recess 120 of the partition member main body 58, and the lower lid member 118 is superimposed on the lower end surface of the partition member main body 58. Thereby, the outer periphery fixing | fixed part 114 of the movable rubber film 64 is clamped by the fitting recessed part 120 and the support recessed part 122 in a compressed state. Note that the holding and fixing force of the lower lid member 118 is exerted via the caulking portion 32 of the second mounting bracket 14 and the fixing bracket 48 when the partition member 52 described later is assembled to the second mounting bracket 14. It is like that. In this way, the movable rubber film 64 is assembled to the lower end portion of the partition member main body 58 in a state where the elastic deformation of the central portion thereof is allowed, and the downward opening of the partition member main body 58 has a movable rubber film. 64 is fluid-tightly covered. The lower lid member 118 is formed with a communication hole 123 penetrating in the thickness direction, and the connection hole 123 is connected to the second through-hole 78 in the assembled state to the partition member main body 58. Thus, the second circumferential groove 72 is opened on the lower surface of the partition member 52 through the second through hole 78 and the communication hole 123.

  The spring rigidity of the movable rubber film 64 is to prevent the intermediate chamber 128, which will be described later, from functioning as an equilibrium chamber at the time of vibration input, and to ensure the amount of fluid flow in the first orifice passage 130, which will be described later. , At least larger than the spring rigidity of the diaphragm 42. More preferably, in order to secure a fluid flow amount of the second orifice passage 132 described later, the second orifice passage 132 is large enough not to absorb medium-frequency amplitude vibration in the tuning frequency range of the second orifice passage 132. Spring stiffness is set. The spring rigidity of the movable rubber film 64 can be appropriately set by changing the forming material, shape, etc. of the movable rubber film 64.

  The partition member 52 having such a structure is inserted into the cylindrical portion 26 of the second mounting bracket 14 from the lower opening, and the partition member is formed with respect to the step portion 40 formed in the seal rubber layer 38. The outer periphery of the upper surface of the main body 58 is overlapped in the axial direction, and the outer periphery of the lower surface of the lower lid member 118 is overlapped with the upper end surface of the fixing bracket 48 and sandwiched between the stepped portion 40 and the fixing bracket 48. Positioned in the axial direction. Then, the diameter of the second mounting bracket 14 is reduced, and the caulking portion 32 is caulked, so that the outer peripheral surface of the partition member main body 58 passes through the seal rubber layer 38 and the cylinder of the second mounting bracket 14. The partition member main body 58 is elastically fitted and supported on the cylindrical portion 26 of the second mounting bracket 14 through the seal rubber layer 38 by being pressed against the inner peripheral surface of the shaped portion 26. .

  As described above, the partition member 52 is accommodated and disposed so as to spread in the direction perpendicular to the axis in the fluid chamber 50 with respect to the cylindrical portion 26 of the second mounting member 14, so that the fluid chamber 50 is separated from the partition member 52. Divided up and down. Thereby, a part of the wall portion is constituted by the main rubber elastic body 16 on the upper side in the axial direction of the partition member 52, and pressure fluctuation is caused based on elastic deformation of the main rubber elastic body 16 at the time of vibration input. While the chamber 124 is formed, on the lower side in the axial direction of the partition member 52, a part of the wall portion is constituted by the diaphragm 42, and the volume change due to the deformation of the diaphragm 42 is easily allowed. Is formed.

  In the partition member 52, the upper opening portion of the partition member main body 58 is covered with the movable partition wall 62 and the supporting rubber elastic body 60, and the lower opening portion is covered with the movable rubber film 64. An intermediate chamber 128 is formed. As a result, the partition wall portion of the partition member 52 between the intermediate chamber 128 and the pressure receiving chamber 124 includes the movable partition wall 62, and the second upper communication hole is formed on the upper surface of the movable rubber plate 106 provided in the movable partition wall 62. The pressure of the pressure receiving chamber 124 is applied through 96, while the pressure of the intermediate chamber 128 is applied to the lower surface of the movable rubber plate 106 through the second lower communication hole 92. Further, a partition wall portion of the partition member 52 between the intermediate chamber 128 and the equilibrium chamber 126 includes the movable rubber film 64, and the pressure of the intermediate chamber 128 is exerted on the upper surface of the movable rubber film 64, while the movable rubber film. The pressure of the equilibrium chamber 126 is applied to the lower surface of 64.

  Furthermore, in the present embodiment, a communication hole that connects the pressure receiving chamber 124 and the equilibrium chamber 126 is formed by the first upper communication hole 94 and the first lower communication hole 90 provided in the movable partition wall 62. A one-way valve comprising an annular rubber plate 102 and a coil spring 104 is disposed in a first accommodation space 98 provided between the first upper communication hole 94 and the first lower communication hole 90. The annular rubber plate 102 is overlapped from the opening side on the first accommodation cavity 98 side of the first lower communication hole 90 constituting the communication hole, in other words, from the opening side on the pressure receiving chamber 124 side. Has been.

  Further, the first circumferential groove 70 and the second circumferential groove 72 opened on the outer peripheral surface of the partition member 52 are covered with a seal rubber layer 38 in a fluid-tight manner. Thereby, the 1st orifice channel | path 130 extended in the outer peripheral part of the partition member 52 by a length of a little less than 2 rounds using the 1st circumferential groove 70 and the 2nd circumferential groove 72 is formed, and this 1st One end of the orifice passage 130 in the circumferential direction is connected to the pressure receiving chamber 124 through the first through hole 76, and the other end is connected to the equilibrium chamber 126 through the second through hole 78 and the communication hole 123. , The pressure receiving chamber 124 and the equilibrium chamber 126 are communicated with each other through the first orifice passage 130. Further, a second orifice passage 132 is formed using the second circumferential groove 72 to extend the outer peripheral portion of the partition member 52 with a length of a little less than one round. The end portion is connected to the intermediate chamber 128 through the third through hole 80, and the other end portion is connected to the equilibrium chamber 126 through the second through hole 78 and the communication hole 123. 128 and the equilibrium chamber 126 are in communication with each other through the second orifice passage 132.

  In the present embodiment, the resonance frequency of the fluid that flows through the first orifice passage 130 based on the relative pressure fluctuation generated between the pressure receiving chamber 124 and the equilibrium chamber 126 at the time of vibration input is 10 Hz. It is tuned so that the anti-vibration effect (high damping effect) based on the resonance action of the fluid etc. is advantageously exhibited against the low frequency engine shake. Further, the resonance frequency of the fluid that is caused to flow through the second orifice passage 132 based on the relative pressure fluctuation generated between the intermediate chamber 128 and the equilibrium chamber 126 at the time of vibration input is determined by the first orifice passage 130. It is tuned so as to advantageously exhibit a vibration isolation effect (low dynamic spring effect) based on the resonance action of the fluid with respect to idling vibration at a medium frequency of about 15 Hz to 30 Hz, which is higher than the tuning frequency. The tuning of the first orifice passage 130 and the second orifice passage 132 is performed by, for example, the rigidity of the wall springs of the pressure receiving chamber 124, the equilibrium chamber 126, and the intermediate chamber 128 (the amount of pressure change necessary for changing the unit volume). The pressure fluctuation transmitted through the orifice passages 130 and 132 is generally adjusted by adjusting the passage length and passage sectional area of each orifice passage 130 and 132 in consideration of the characteristic value corresponding to Can be grasped as the tuning frequency of the orifice passages 130 and 132.

  Further, particularly in this embodiment, the movable partition wall 62 is elastically supported by the partition member main body 58 via the support rubber elastic body 60 so as to be vertically displaceable, so that the movable partition wall 62 as a mass system can be obtained. And a sub-vibration system (dynamic damper) including the support rubber elastic body 60 as a spring system. In this case, the natural frequency of the movable partition wall 62 is tuned to a frequency range higher than the tuning frequency of the second orifice passage 132, for example, about 250 Hz to 400 Hz. The natural frequency of the movable partition wall 62 can be tuned by changing the forming material and shape of the movable partition wall 62 and the supporting rubber elastic body 60. However, the dynamic damper mass including the movable partition wall 62 can be tuned. As a component, in addition to the mass of the movable partition wall 62, it is necessary to consider a fluid mass between the movable partition wall 62 and the movable rubber film 64 that are integrally displaced with the movable partition wall 62, while the spring component includes a support rubber elasticity. Since it is necessary to consider not only the spring component of the body 60 but also the spring component of the movable rubber film 64, the spring component of the pressure receiving chamber 124 and the equilibrium chamber 126 (expansion spring component), etc. The natural frequency is tuned in a state where the engine mount 10 is mounted on the power unit.

  In addition, particularly in the present embodiment, the partition member main body 58 is elastically supported with respect to the tubular portion 26 via the seal rubber layer 38. Thus, another sub-vibration system (dynamic damper) including the partition member 52 as the mass system and the seal rubber layer 38 as the spring system is configured. In the present embodiment, the movable partition wall 62 and the supporting rubber elasticity are formed. A series two-degree-of-freedom vibration model is realized by the dynamic damper configured including the body 60 and the dynamic damper configured including the partition member main body 58 and the seal rubber layer 38. Here, if the natural frequency of the partition member 52 is in a frequency range higher than the tuning frequency of the second orifice passage 132, the natural frequency of the movable partition wall 62 is considered in consideration of the required vibration damping characteristics and the like. It may be tuned to a higher frequency range or may be tuned to a lower frequency range. The natural frequency of the partition member 52 can be tuned by changing the material and shape of the partition member 52 and the seal rubber layer 38. Preferably, the engine mount 10 is similar to the movable partition wall 62. It is carried out under the condition of mounting on the power unit.

  In the engine mount 10 having such a structure, the bolt hole 24 of the first mounting bracket 12 is screwed and fixed to the mounting member on the power unit side using a fixing bolt (not shown), and the second mounting bracket 14 The cylindrical portion 26 and the like are fixed to an outer bracket (not shown), and the outer bracket is fixed to a mounting member on the vehicle body side with a bolt or the like. As a result, the engine mount 10 is mounted between the power unit and the vehicle body, and the power unit is supported in a vibration-proof manner with respect to the vehicle body.

  For example, when a low-frequency large-amplitude vibration such as an engine shake is input, a relative pressure fluctuation is caused between the pressure receiving chamber 124 and the equilibrium chamber 126 and the fluid flows through the first orifice passage 130. The anti-vibration effect (high damping effect) based on the resonance action of the fluid is exhibited. In this case, since the natural frequency of the movable partition wall 62 and the partition member 52 is tuned to a higher frequency range than the tuning frequency of the first orifice passage 130, the movable partition wall 62 and the partition member 52 are hardly displaced. At the same time, when a large amplitude vibration such as an engine shake is input, the amount of displacement of the movable rubber plate 106 is limited. Therefore, the pressure absorption of the pressure receiving chamber 124 due to the displacement of the movable partition wall 62, the partition member 52, and the movable rubber plate 106. Little effect occurs. In particular, in the present embodiment, the second upper communication hole 96 and the second lower communication hole 92 are sealed by the inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110 of the movable rubber plate 106. A short circuit between the pressure receiving chamber 124 and the intermediate chamber 128 through the communication holes 96 and 92 can be advantageously avoided, and the possibility that the pressure in the pressure receiving chamber 124 is released to the intermediate chamber 128 is further reduced. Therefore, a large pressure fluctuation is effectively induced in the pressure receiving chamber 124, and a fluid flow amount through the first orifice passage 130 can be sufficiently secured, which is an effective prevention against low frequency large amplitude vibration such as engine shake. The vibration effect is demonstrated.

  On the other hand, at the time of inputting medium frequency medium amplitude vibration such as idling vibration, the first orifice passage 130 is substantially clogged, and the pressure fluctuation in the pressure receiving chamber 124 acts on the movable partition wall 62. Since the natural frequency of the movable partition wall 62 and the partition member 52 is tuned to a higher frequency range than the tuning frequency of the second orifice passage 132, the movable partition wall 62 and the partition member 52 are hardly displaced. The pressure fluctuation in the pressure receiving chamber 124 acts on the movable rubber plate 106. Based on the displacement of the movable rubber plate 106, the pressure fluctuation in the pressure receiving chamber 124 is transmitted to the intermediate chamber 128. As a result, an anti-vibration effect (low dynamic spring effect) based on the resonance action of the fluid flowing through the second orifice passage 132 is exhibited.

  Further, when a high frequency vibration such as a traveling boom noise in a frequency range higher than the tuning frequency of the second orifice passage 132 is input, the first orifice passage 130 and the second orifice passage 132 are substantially It becomes clogged. In particular, in this embodiment, since the natural frequencies of the movable partition wall 62 and the partition member 52 are respectively tuned to the frequency range of the high frequency vibration, each of the configurations including the movable partition wall 62 and the partition member 52 is provided. The vibration energy absorption effect due to the resonance action of the dynamic damper is exhibited, and the pressure fluctuation in the pressure receiving chamber 124 is released to the equilibrium chamber 126 via the movable rubber film 64. As a result, the vibration damping effect of the dynamic damper and the pressure reducing effect of the pressure receiving chamber 124 exhibit an effective vibration damping effect against high frequency vibration. In particular, in the present embodiment, the entire partition member 52 is elastically supported by the second mounting member 14 via the seal rubber layer 38, so that the movable partition wall 62, the support rubber elastic body 60, the partition member 52, and the seal rubber. A series two-degree-of-freedom vibration model including the layer 38 is realized, and it is possible to obtain a more excellent degree of freedom of tuning and a damping effect.

  In particular, according to the present embodiment, the movable rubber film 64 is provided in the partition wall portions of the intermediate chamber 128 and the equilibrium chamber 126, so that the volume change of the intermediate chamber 128 is allowed and the displacement amount of the movable partition wall 62 is sufficiently large. Therefore, the effect of the dynamic damper including the movable partition wall 62 as the mass member can be effectively exhibited. Further, particularly in the present embodiment, since the anti-vibration effect against high-frequency vibration is exhibited by the displacement of the movable partition wall 62 and the partition member 52, the effective anti-vibration effect against high-frequency vibration is exhibited regardless of the magnitude of the amplitude. I can do it.

  In addition, when a large vibration load is input between the first mounting bracket 12 and the second mounting bracket 14 and an excessive negative pressure is generated in the pressure receiving chamber 124, the pressure receiving chamber 124 and the intermediate chamber 128. An annular rubber plate 102 disposed between the first upper communication hole 94 and the first lower communication hole 90 communicating with the first lower communication hole against the biasing force of the coil spring 104. Separated from 90 openings. Accordingly, the intermediate chamber 128 and the pressure receiving chamber 124 are communicated with each other through the first upper communication hole 94 and the first lower communication hole 90, and an excessive negative pressure in the pressure receiving chamber 124 is caused by fluid inflow from the intermediate chamber 128. It can be resolved quickly. As a result, the occurrence of cavitation is suppressed, and the generation of abnormal noise and vibration that are considered to be caused by cavitation can be effectively suppressed.

  Here, since the annular rubber plate 102 is overlapped from the opening side of the first lower communication hole 90 on the pressure receiving chamber 124 side, the biasing direction of the annular rubber plate 102 by the coil spring 104 is the pressure receiving chamber. The direction in which the positive pressure from 124 is exerted is approximately equal. As a result, the annular rubber plate 102 is maintained in a closed state when a positive pressure is applied from the pressure receiving chamber 124, and is a one-way valve that opens only when a negative pressure is applied from the pressure receiving chamber 124. Yes. Therefore, when a positive pressure is applied from the pressure receiving chamber 124, the closed state of the first lower communication hole 90 is maintained at a high level, and the relative pressure fluctuation between the pressure receiving chamber 124 and the equilibrium chamber 126 changes. Elicited effectively. Then, by applying the positive pressure of the pressure receiving chamber 124 to the annular rubber plate 102, the closed state of the first lower communication hole 90 can be maintained more firmly. Further, since the annular rubber plate 102 is formed of a rubber elastic body, the closed state of the first lower communication hole 90 is more stably expressed, and the movable partition wall 62 is struck at the time of closing operation. Sound is also reduced.

  In addition, the urging force of the coil spring 104 is such that the annular rubber plate 102 is separated from the opening of the first lower communication hole 90 only when an excessive negative pressure is generated to such an extent that cavitation can occur in the pressure receiving chamber 124. When the vibration is input to such an extent that the operation of the dynamic damper including the first orifice passage 130, the second orifice passage 132, and the movable partition wall 62 is manifested. The closed state of the first lower communication hole 90 is maintained. Thereby, generation | occurrence | production of abnormal noise and a vibration can be suppressed, ensuring the vibration proofing effect by these orifice passages 130 and 132 and a dynamic damper effectively.

  Further, particularly in the present embodiment, the pressing position to the annular rubber plate 102 at the end portion on the small diameter side of the coil spring 104 is set above the central portion of the first lower communication hole 90. Thereby, the closed state of the first lower communication hole 90 by the annular rubber plate 102 can be expressed more stably, and the first lower communication hole is elastically deformed by the annular rubber plate 102 itself. The risk of opening 90 is also reduced. Therefore, particularly in the present embodiment, by using a coil spring having a tapered shape as the coil spring 104, the end portion on the large diameter side is replaced by the partition wall portion 88 constituting the peripheral wall of the first accommodation region 98. Positioning can be performed in the radial direction, and as a result, the pressing position of the end portion on the small diameter side to the annular rubber plate 102 can be easily and accurately positioned. At the same time, the positional deviation in the radial direction of the end portion on the large diameter side of the coil spring 104 is also suppressed. As a result, the positional deviation of the pressing position on the annular rubber plate 102 at the end portion on the small diameter side can be advantageously reduced. Furthermore, since the outer diameter dimension of the annular rubber plate 102 is set to be slightly smaller than the inner diameter dimension of the partition wall portion 88, the partition wall portion 88 constitutes a vertical guide structure for the annular rubber plate 102. In addition, the operation of the annular rubber film 102 can be expressed more stably, and the radial displacement of the annular rubber plate 102 is suppressed, so that the annular rubber plate 102 may be detached from the first lower communication hole 90. Has also been avoided.

  Further, particularly in the present embodiment, the movable partition wall 62 including the movable rubber plate 106 and the annular rubber plate 102 is elastically supported by the second mounting member 14 via the support rubber elastic body 60. As a result, even if the movable rubber plate 106 or the annular rubber plate 102 strikes the movable partition wall 62 due to excessive pressure fluctuation or the like, for example, transmission of sound and vibration due to this to the second mounting bracket 14 is transmitted. It can be reduced by the support rubber elastic body 60. In addition, particularly in this embodiment, the partition member main body 58 to which the movable partition wall 62 is connected is supported by the second mounting member 14 via the seal rubber layer 38. As a result, transmission of abnormal noise and vibration due to the contact of the movable rubber plate 106 and the annular rubber plate 102 to the movable partition wall 62 to the second mounting bracket 14 is transmitted between the support rubber elastic body 60 and the seal rubber layer 38. It is possible to significantly reduce, and more effective noise and vibration reduction effects are exhibited.

  Next, FIG. 3 shows an engine mount 140 for an automobile as a second embodiment of the fluid filled type vibration damping device having a structure according to the present invention. In the following description, members and parts that are substantially the same as those of the first embodiment are denoted by the same reference numerals as those of the above-described embodiment, and detailed description thereof is omitted.

  The engine mount 140 in the present embodiment does not have the annular rubber plate 102 and the coil spring 104 constituting the one-way valve as compared to the first embodiment, and the shape of the movable rubber plate 142 as a movable plate. Is different.

  More specifically, the partition wall main body 144 constituting the movable partition wall 62 in the present embodiment has a substantially bottomed cylindrical shape opening upward, in which the partition wall portion 88 of the partition wall body 82 in the first embodiment is omitted. Has been. Then, the cover member 84 is overlapped and fixed to the upper opening portion of the partition wall main body 144, so that an accommodation space 146 is formed between the partition wall main body 144 and the cover member 84.

  A movable rubber plate 142 serving as a movable plate is accommodated in the accommodation space 146. The movable rubber plate 142 has a substantially disc shape as a whole, and has a structure integrally including a hard portion 148 constituting a deformation restraining region and an outer peripheral elastic portion 150 constituting a deformation allowable region. .

  The hard portion 148 has a thin disk shape formed of a metal such as iron or aluminum alloy or a hard synthetic resin. On the other hand, the outer peripheral elastic portion 150 is formed of a rubber elastic body, and the outer peripheral elastic portion 150 is formed so as to cover the entire outer surface of the hard portion 148. Further, an outer peripheral elastic protrusion 110 and an inner peripheral elastic protrusion 108, which are the same as those of the movable rubber plate 106 in the first embodiment, are integrally formed at the outer peripheral edge portion and the radial intermediate portion of the outer peripheral elastic portion 150. Yes. The first lower communication hole 90 in the present embodiment is formed in a circular shape in the center portion of the bottom wall portion 86 of the partition wall main body 144 so as to penetrate in the thickness direction. Accordingly, the communication holes 90 to 96 formed in the movable partition wall 62 are sealed by the outer peripheral elastic protrusion 110 and the inner peripheral elastic protrusion 108, respectively, and the pressure receiving chamber 124 and the intermediate chamber are passed through the communication holes 90 to 96, respectively. 128 is prevented from being short-circuited.

  The movable rubber plate 142 having such a structure is accommodated in the accommodation space 146. As a result, the movable rubber plate 142 is slightly displaced in the axial direction of the movable rubber plate 142 by elastically deforming the inner circumferential elastic projection 108 and the outer circumferential elastic projection 110 in the axial direction within the accommodation space 146. Is allowed, and the displacement of the movable rubber plate 142 is limited in a buffering manner based on the elasticity of the inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110.

  Also in the present embodiment, as in the first embodiment, an effective anti-vibration effect can be exhibited for any of a plurality of types of vibrations ranging from a low frequency region to a high frequency region. In particular, according to this aspect, since the movable rubber plate 142 is provided with the hard portion 148, the shape stability of the movable rubber plate 142 can be more effectively ensured, and the movable rubber plate 142 when the medium frequency vibration is input. The effect of absorbing the pressure fluctuation in the pressure receiving chamber 124 due to the minute displacement of the pressure is more effectively exhibited. As is clear from this embodiment, the annular rubber plate 102 and the coil spring 104 constituting the one-way valve in the first embodiment are not necessarily required in the present invention.

  Next, FIG. 4 shows an engine mount 160 for an automobile as a third embodiment of the fluid filled type vibration damping device structured according to the present invention. The engine mount 160 has substantially the same structure as the engine mount 10 in the first embodiment.

  In particular, in the present embodiment, the fixing bracket 162 as an annular fixing bracket connected to the outer peripheral portion of the diaphragm 42 has a shallow, substantially bottomed cylindrical shape as a whole. And the center part of the bottom part of the fixture 162 is protruded slightly upwards, and further, a through hole 164 penetrating in the thickness direction is formed in the center part. Here, the diameter dimension of the through hole 164 is smaller than the diameter dimension of the lower end surface of the partition member 52, specifically, the lower end surface of the lower lid member 118. An annular fixing portion 166 formed on the outer peripheral edge of the diaphragm 42 is vulcanized and bonded so as to cover the entire fixing bracket 162. Accordingly, the inner diameter dimension of the annular fixing portion 166 is made smaller than the diameter dimension of the lower end surface of the partition member 52.

  In addition, the cylindrical part 26 of the 2nd attachment metal fitting 14 in this embodiment is diameter-expanded slightly from the positioning step part 168 formed in the lower end part. Then, the fixing bracket 162 is inserted from the lower end opening of the cylindrical portion 26 to a position where the upper end surface of the annular fixing portion 166 is locked by the positioning step portion 168. The fixing fitting 162 is fitted and fixed to the tubular portion 26 by being caulked and fixed by the caulking portion 32.

  In such an assembled state, an annular fixing portion 166 that covers the fixing bracket 162 is interposed between the lower end surface of the partition member 52 and the fixing bracket 162. In the present embodiment, the annular fixing portion 166 axially contacts the fixing bracket 162. A rubber contact is formed. The partition member main body 58 of the partition member 52 has an upper end surface abutted against the stepped portion 40 of the main rubber elastic body 16, while a lower end surface thereof is an upper end surface of the annular fixing portion 166 via the lower lid member 118. And is elastically supported in the axial direction between the stepped portion 40 and the annular fixing portion 166. In particular, in the present embodiment, since the fixing bracket 162 is positioned below the partition member 52 in the axial direction, the shape of the annular fixing portion 166 can be stably held, and the partition member 52 can be more stably maintained. It is possible to support. In the present embodiment, the seal rubber layer 38 extends to reach the positioning stepped portion 168, and a ring between the outer peripheral surface of the fixing bracket 162 and the cylindrical portion 26 is wrapped around the outer periphery of the fixing bracket 162. It is fluid-tightly sealed with the fixing portion 166.

  According to this embodiment, by adjusting the elasticity of the rubber elastic body constituting the annular fixing portion 166 as the axial contact rubber and the shape and size of the annular fixing portion 166, the elastic support characteristic of the partition member 52 is improved. Therefore, the degree of freedom of adjustment of the dynamic damper including the partition member 52 as a mass member can be increased.

  Further, since the annular fixing portion 166 is interposed between the partition member 52 and the fixing bracket 162, the annular fixing portion 166 generates abnormal noise and vibration caused by the movable rubber plate 106 and the like strongly hitting the movable partition wall 62. The noise can be absorbed, and the transmission of the abnormal sound and vibration from the partition member 52 to the second mounting bracket 14 via the fixing bracket 162 can be further reduced.

  In particular, in the present embodiment, the axial contact rubber is formed by using the annular fixing portion 166 formed integrally with the diaphragm 42, so that the number of parts can be reduced and the number of assembling steps can be reduced.

  Next, FIG. 5 shows an engine mount 170 as a fourth embodiment of the present invention. The engine mount 170 has substantially the same structure as the engine mount 140 as the second embodiment.

  In particular, in this embodiment, the integral vulcanization molded product including the partition member 52 and the fixing metal 48 is disposed at a predetermined distance in the axial direction, and the lower end surface of the partition member 52, specifically, A protruding piece 172 as an axial contact rubber is interposed between the lower end surface of the lower lid member 118 and the upper surface of the fixing bracket 48. The projecting piece 172 is integrally formed with the seal rubber layer 38 so as to project inward in the radial direction. Thus, the protruding piece portion 172 has a substantially annular shape, and the inner diameter dimension thereof is smaller than the outer diameter dimension of the lower end surface of the partition member 52. In particular, in the present embodiment, the protruding piece portion 172 is protruded to such an extent that the radially inward protruding end surface is substantially the same radial position as the inner peripheral surface of the fixture 48. In the present embodiment, the annular fixing portion 46 that connects the diaphragm 42 to the fixing bracket 48 has a larger radial width than the second embodiment described above, and has a diameter substantially equal to that of the fixing bracket 48. It is a substantially large-diameter ring shape having a directional width dimension and an axial length dimension.

  The protruding piece 172 is inserted from the lower end opening of the cylindrical portion 26 with the partition member 52 and the fixing bracket 48 being separated from each other by a predetermined distance in the axial direction, and the cylindrical portion 26 is subjected to diameter reduction processing. Thus, as a result of the partition member 52 and the fixing metal 48 biting into the seal rubber layer 38, the seal rubber layer 38 is formed to protrude radially inward between the partition member 52 and the fixing metal 48.

  The protruding piece 172 is formed between the partition member 52 and the fixing bracket 48 by the diameter reducing process, with the inner peripheral surface of the seal rubber layer 38 before the diameter reducing process is performed on the cylindrical part 26 as a flat surface. Although it may be formed by the seal rubber layer 38 biting inward in the radial direction, in particular in the present embodiment, before the diameter reduction processing is performed on the cylindrical portion 26, partitioning is performed on the inner peripheral surface of the seal rubber layer 38 in advance. Positioning grooves 174 and 174 are formed at positions where the member 52 and the fixing bracket 48 bite, respectively, and a protruding piece serving as a protruding piece portion 172 is formed between the positioning grooves 174 and 174. Then, the cylindrical portion 26 is subjected to diameter reduction processing so that the partition member 52 and the fixing bracket 48 are fitted in the positioning grooves 174 and 174, and the protruding pieces between the positioning grooves 174 and 174 are formed in the partition member 52. The protruding piece 172 is formed by protruding further inward in the radial direction between the fixing bracket 48 and the fixing bracket 48. In this way, the protruding piece portion 172 can be formed with higher accuracy, and positioning of the partition member 52 and the fixing bracket 48 is facilitated.

  In this way, the protruding piece 172 is interposed between the partition member 52 and the fixing bracket 48, and the partition member main body 58 of the partition member 52 has the stepped portion 40 and the protruding piece 172 of the main rubber elastic body 16. Are elastically supported in the axial direction. Also in the present embodiment, the elastic support characteristic of the partition member 52 can be adjusted by adjusting the member elasticity, shape, size, and the like of the protruding piece 172, and the movable rubber plate 106 and the like can be used as the movable partition wall 62. The projecting piece 172 can absorb the abnormal noise and vibration resulting from the strong impact. Also in this embodiment, the projecting piece 172 as the axial contact rubber is integrally formed with the seal rubber layer 38, so that the number of parts and assembly man-hours can be reduced.

  FIG. 6 shows the result of measuring the dynamic spring constant of the engine mount 10 having the structure according to the first embodiment with different input vibration frequencies. From FIG. 6, it can be confirmed that the fluid-filled vibration isolator having a structure according to the present invention exhibits an effective low dynamic spring effect in a high frequency range of about 270 Hz to 400 Hz.

  As mentioned above, although several embodiment of this invention has been explained in full detail, these are illustrations to the last, Comprising: This invention is not limited at all by the specific description in this embodiment. .

  For example, as described above, the annular rubber plate 102 and the coil spring 104 in the first embodiment are not necessarily required, but the biasing means of the valve body is not necessarily limited to a metal coil spring. Alternatively, for example, rubber or elastic synthetic resin can be used, or a leaf spring or the like can be used. Also, as the valve body, not only a rubber elastic body but also a hard material such as metal or resin can be used.

  Further, the movable rubber plates 106 and 142 in each of the above-described embodiments are both in a state in which the inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110 are brought into contact with the inner surface of the accommodation region and pre-compressed. Thus, a minute displacement is allowed by the pressure action of the pressure receiving chamber 124 based on the elasticity of the rubber film itself, but the movable rubber plates 106 and 142 are accommodated with a gap from the inner surface of the accommodation area. It may be arranged so that it can be displaced minutely in the thickness direction. Further, the specific shape of the movable plate is not limited to the shape as described above, and for example, the inner peripheral elastic protrusion 108 and the outer peripheral elastic protrusion 110 are not necessarily required.

  Furthermore, in each of the above embodiments, the dynamic damper is configured including the movable partition wall 62 and the support rubber elastic body 60, and further the dynamic damper is configured including the partition member 52 and the seal rubber layer 38. Although further improvement of the degree of freedom of tuning and further improvement of the anti-vibration effect against input vibration in the high frequency range have been attempted, a dynamic damper configuration using the partition member 52 and the seal rubber layer 38 is not necessarily required. For example, the natural frequency of the partition member 52 may be tuned to a frequency range that is out of the frequency range of the vibration to be damped so that the partition member 52 does not substantially function as a dynamic damper.

  In the third embodiment, an annular fixing portion 166 as an axial contact rubber is integrally formed with the diaphragm 42, whereas in the fourth embodiment, a protrusion as an axial contact rubber. Although the piece 172 is integrally formed with the seal rubber layer 38, the axial contact rubber does not necessarily have to be integrally formed with the flexible film, the main rubber elastic body, etc. Of course, it is also possible to form with a member. For example, in the engine mount 170 according to the fourth embodiment, instead of the projecting piece 172, a rubber elastic body formed as a single piece with an annular plate shape is used as an axial contact rubber, and between the partition member 52 and the fixing bracket 48. It may be interposed between the two.

  Furthermore, a displacement amount limiting mechanism for limiting the displacement amount of the movable rubber film 64 may be provided in order to avoid damage due to an excessive displacement of the movable rubber film 64 as the elastic movable film in the embodiment. Such a displacement amount limiting mechanism, for example, abuts on both sides of the movable rubber film 64 in the displacement direction when the movable rubber film 64 is excessively displaced, thereby limiting the excessive displacement of the movable rubber film 64. It can be easily realized by providing a wall portion to be used. However, such a displacement limit mechanism of the elastic movable film limits the displacement only when the elastic movable film is excessively displaced while ensuring the amount of displacement of the elastic movable film at the time of high frequency vibration input. Is preferred.

The longitudinal cross-sectional view of the engine mount as 1st embodiment of this invention. The principal part expansion longitudinal cross-sectional view of the engine mount. The longitudinal cross-sectional view of the engine mount as 2nd embodiment of this invention. The longitudinal cross-sectional view of the engine mount as 3rd embodiment of this invention. The longitudinal cross-sectional view of the engine mount as 4th embodiment of this invention. The graph which shows the dynamic spring characteristic of the fluid enclosure type vibration isolator made into the structure according to this invention.

Explanation of symbols

10: engine mount, 12: first mounting bracket, 14: second mounting bracket, 16: main rubber elastic body, 42: diaphragm, 50: fluid chamber, 52: partition member, 60: support rubber elastic body, 62 : Movable partition wall, 64: movable rubber film, 106: movable rubber plate, 124: pressure receiving chamber, 126: equilibrium chamber, 128: intermediate chamber, 130: first orifice passage, 132: second orifice passage

Claims (7)

The first mounting member and the second mounting member are connected by a main rubber elastic body, and a pressure receiving chamber in which a part of the wall portion is configured by the main rubber elastic body and a part of the wall portion is a flexible film. A fluid-filled vibration isolating system that forms a configured equilibrium chamber, encloses an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and has a first orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other. In the device
A partition member that partitions the pressure receiving chamber and the equilibrium chamber is supported by the second mounting member to form an intermediate chamber inside the partition member, and a partition wall portion between the intermediate chamber and the pressure receiving chamber in the partition member The outer periphery of the partition member is constituted by a movable partition wall supported by a support rubber elastic body and allowed to be elastically displaced, while the partition portion between the intermediate chamber and the equilibrium chamber of the partition member is formed by an elastic movable film, Furthermore, a movable plate with a limited displacement amount is provided on the movable partition wall so that the pressure of the pressure receiving chamber is exerted on one surface of the movable plate and the pressure of the intermediate chamber is exerted on the other surface. A second orifice passage is provided for communicating the intermediate chamber with the equilibrium chamber, and the second orifice passage is tuned to a higher frequency region than the first orifice passage, while being supported by the support rubber elastic body. Natural vibration of movable bulkhead The fluid filled type vibration damping device, characterized in that to constitute a dynamic damper tune further the high frequency range than said second orifice passage.   The movable partition wall is provided with a communication hole that connects the pressure receiving chamber and the intermediate chamber, a valve body that closes the communication hole is provided, and an urging means that exerts an urging force in the closing direction on the valve body. An opening direction of the valve body against an urging force against a negative pressure action from the pressure receiving chamber while maintaining a closed state against a positive pressure action from the pressure receiving chamber side. The fluid-filled vibration isolator according to claim 1, wherein the operation is allowed.   The fluid-filled vibration isolator according to claim 2, wherein the biasing means that exerts a biasing force on the valve body is configured using a metal coil spring.   The fluid-filled vibration isolator according to claim 2 or 3, wherein the valve body is formed of a rubber elastic body, and is overlapped from the opening side of the communication hole in the pressure receiving chamber side.   The second mounting member includes a cylindrical portion, and the first mounting member is spaced apart on one axial side of the cylindrical portion, while the partition member includes the cylindrical portion. A cylindrical fixing portion that is fitted and fixed to the portion is provided, and the movable partition wall and the elastic movable film are supported by the cylindrical fixing portion. The fluid-filled vibration isolator described in 1.   The movable partition wall is connected to the cylindrical fixing portion of the partition member via the support rubber elastic body, and a covering rubber layer is attached to the inner peripheral surface of the cylindrical portion of the second mounting member. The fluid-filled vibration isolator according to claim 5, wherein the fluid-filled vibration isolator is formed and elastically fitted and supported to the cylindrical portion through the covering rubber layer.   Axial contact between an annular fixing bracket connected to the outer peripheral portion of the flexible membrane and fitted and fixed to the cylindrical portion of the second mounting bracket, and the cylindrical fixing portion of the partition member The rubber is interposed, and the cylindrical fixing portion is elastically supported in the axial direction between the axial contact rubber and a step portion formed in the main rubber elastic body. Fluid-filled vibration isolator.

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