JP2010078109A - Fluid enclosed type vibration isolator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid enclosed type vibration isolator which has a novel construction and can reveal a vibration isolating effect against the vibration of a plurality of frequency bands. <P>SOLUTION: The fluid enclosed type vibration isolator composes the bulkhead parts of a pressure receiving chamber 114 and an intermediate chamber 118 by a movable bulkhead 50 on which elastic displacement is allowed, composes the bulkhead parts of the intermediate chamber 118 and an equalizing chamber 116 by an elastic movable membrane 52, and composes a dynamic damper by tuning up the second orifice passage 122 bringing the intermediate chamber 118 into fluid communication with the pressure receiving chamber 114 to a higher frequency zone than the first orifice passage 120 bringing the equalizing chamber 116 into fluid communication with the pressure receiving chamber 114 and further tuning up the natural frequency of the movable bulkhead 50 to a higher frequency zone than the second orifice passage 122 and further provides nonlinear stopper mechanisms 92, 56, 94, 98 which nonlinearly limit an amount of displacement of the movable bulkhead 50. <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. An object of the present invention is to provide a fluid-filled vibration isolator having a novel structure capable of exerting a vibration 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 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 communicating with either one of the pressure receiving chamber and the equilibrium chamber is provided, and the second orifice passage is tuned to a higher frequency region than the first orifice passage. A dynamic damper is configured by tuning the natural frequency of the supported movable partition wall to a higher frequency range than the second orifice passage, and a pair of the partition members facing each other on both sides in the displacement direction of the movable partition wall. By disposing a non-linear spring between the movable bulkhead and the pair of displacement regulating sections, the movable bulkhead is displaced nonlinearly on both sides in the displacement direction. In that a nonlinear stopper mechanism for restricting, characterized.

  According to this aspect, the first orifice passage is tuned to low frequency large amplitude vibration such as engine shake. And the movable partition which comprises the partition part of a pressure receiving chamber and an intermediate | middle chamber is restrict | limited nonlinearly by the nonlinear stopper mechanism. Here, non-linear means that the increase in the spring constant with respect to the increase in the deformation amount in the elastic deformation region changes more than the proportional relationship. The change mode is not particularly limited, and includes a mode in which a certain amount of change suddenly changes to a polygonal line, changes to a two-dimensional or multi-dimensional function, or changes in multiple stages step by step. . As a result, the support spring rigidity of the nonlinear stopper mechanism is increased at the time of large amplitude input, and the displacement of the movable partition wall is limited, so that the pressure absorbing action of the pressure receiving chamber due to the displacement hardly occurs. In addition, when the large amplitude vibration is input, the amount of displacement of the movable plate provided in the movable partition is limited, and thus the pressure fluctuation in the pressure receiving chamber cannot be absorbed. Therefore, a large pressure fluctuation is effectively induced in the pressure receiving chamber. As a result, the relative pressure fluctuation between the pressure receiving chamber and the equilibrium chamber is effectively induced, and the vibration isolation effect (high damping effect) based on the resonance action of the fluid flowing through the first orifice passage is effective. Demonstrated.

  Furthermore, since a non-linear spring is interposed between the movable partition wall and the displacement restricting portion, it is possible to prevent a violent hit of the movable partition wall against the displacement restricting portion, and to prevent the hitting sound and vibration caused by the hitting. Occurrence is also effectively suppressed.

  On the other hand, the second orifice passage may be formed by communicating any of the intermediate chamber and the equilibrium chamber, and the intermediate chamber and the pressure receiving chamber, and is tuned to medium-frequency medium amplitude vibration such as idling vibration. When the medium frequency medium amplitude vibration is input, the first orifice passage is substantially clogged by the anti-resonant action of the fluid, so that the pressure fluctuation in the pressure receiving chamber acts on the movable partition wall. Further, when the medium amplitude vibration is input, the displacement of the movable partition wall is allowed by the nonlinear stopper mechanism, and the displacement of the movable plate provided on the movable partition wall is allowed. Thereby, the pressure fluctuation of the pressure receiving chamber is transmitted to the intermediate chamber by the displacement of the movable partition wall or the movable plate.

  When the second orifice passage is formed by communicating the intermediate chamber and the equilibrium chamber, the spring rigidity of the elastic movable film constituting the partition wall portion between the intermediate chamber and the equilibrium chamber is at least a flexible film. Is set to be higher than the spring rigidity. Thereby, the pressure fluctuation generated in the intermediate chamber is avoided from being absorbed by the elastic movable film, and the relative pressure fluctuation is effectively generated between the intermediate chamber and the equilibrium chamber. 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 effectively exhibited. That is, when the second orifice passage is formed by communicating the intermediate chamber and the equilibrium chamber, the pressure receiving chamber and the intermediate chamber function as a pressure receiving chamber in cooperation with each other, and the vibration isolation by the second orifice passage is performed. The effect is exhibited effectively.

  On the other hand, when the second orifice passage is formed by communicating the intermediate chamber and the pressure receiving chamber, the spring rigidity of the elastic movable film is set lower than the spring rigidity of the movable film. Thus, the volume of the intermediate chamber can be easily changed by elastic deformation of the elastic movable film. As a result, a relative pressure fluctuation is effectively generated between the intermediate chamber and the pressure receiving chamber, and the vibration isolation effect by the second orifice passage is effectively exhibited. That is, when the second orifice passage is formed by communicating the intermediate chamber and the pressure receiving chamber, the intermediate chamber functions as an equilibrium chamber, and the vibration isolation effect by the second orifice passage is effectively exhibited. It will be.

  Furthermore, when a high frequency small amplitude 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 reacts. Although a substantial clogging state occurs due to the resonance action, the displacement of the movable plate provided on the movable partition wall is allowed at the time of inputting such small amplitude vibrations, thereby exhibiting a hydraulic pressure absorbing effect by the movable plate. Further, particularly in this embodiment, a dynamic damper is configured including a movable partition wall, and is tuned to a vibration frequency region that causes a problem in such a high frequency region. At the same time, in the case of small amplitude vibration, the displacement of the movable partition is sufficiently allowed by sufficiently reducing the support spring rigidity of the nonlinear stopper mechanism. As a result, the movable partition wall is in a resonance state, and the effect of absorbing vibration energy due to the resonance action of the dynamic damper is exhibited, and the pressure variation in the pressure receiving chamber is the elastic movable film that forms the partition wall portion of the intermediate chamber and the equilibrium chamber. Will be escaped to 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, by providing a nonlinear stopper mechanism that nonlinearly regulates the amount of displacement of the movable partition that constitutes the dynamic damper, the displacement of the movable partition at the time of small amplitude vibration input is allowed, and the large amplitude vibration is performed. At the time of input, it is possible to limit the amount of displacement of the movable partition wall. As a result, for example, when inputting high-frequency small-amplitude vibrations such as traveling noise, the dynamic damper effect is effectively exhibited by allowing the displacement of the movable partition wall, while when inputting low-frequency large-amplitude vibrations such as engine shake, it is movable. By limiting the amount of displacement of the partition wall, it is possible to avoid the possibility that the pressure fluctuation in the pressure receiving chamber is absorbed and reduced by the displacement of the movable partition wall, and to effectively exhibit the high damping effect by the orifice passage. In other words, both the vibration reduction effect by the dynamic damper and the high damping effect by the orifice passage can be effectively exhibited.

  Moreover, in this aspect, the movable partition 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 secondary vibration system (dynamic damper) configured including the movable partition are configured only by the movable partition and the supporting rubber elastic body or the nonlinear spring alone. It is not a thing. 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. It is necessary to consider not only the spring component of the nonlinear spring but also 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. Therefore, the natural frequency of the movable partition is not sufficient to tune the movable partition, the supporting rubber elastic body, and the nonlinear spring by taking them out into the atmosphere alone. When using as a mount, it should be tuned so that the target natural frequency is exhibited in the mounted state.

  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.

  Note that various biasing means such as a metal spring, a resin spring, and a rubber spring can be appropriately employed as the biasing means in this aspect, but preferably the biasing force that exerts a biasing force on the valve body. A structure in which the means 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. A structure 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 third aspect of the present invention, in the fluid-filled vibration isolator according to the first or second aspect, one of the first attachment member and the second attachment member is attached to a power unit of an automobile. The other is attached to the vehicle body to constitute an automobile engine mount, the first orifice passage is tuned to a low frequency range corresponding to an engine shake, and the second orifice passage is subjected to idling vibration. While being tuned to the corresponding middle frequency range, the hydraulic pressure absorption action on the pressure receiving chamber based on the displacement or deformation of the movable plate is expressed in the high frequency range corresponding to the traveling noise. The natural frequency of the movable bulkhead is tuned to a high frequency range corresponding to a traveling noise. To.

  According to this aspect, the fluid filled type vibration damping device according to the present invention can be suitably used as an engine mount for an automobile. In an automobile in which vibrations in a plurality of frequency ranges are input in accordance with the driving situation or the like, an effective anti-vibration effect can be exhibited for any of the plurality of frequency ranges. That is, the hydraulic pressure absorption action by the movable plate is expressed in a high frequency range, and the resonance frequency of the dynamic damper including the movable partition is removed from the engine shake and idling vibration. When an engine shake or idling vibration is input, the displacement of the movable plate is limited and the rigidity of the support spring of the movable partition is increased, so that the pressure fluctuation relief of the pressure receiving chamber due to the displacement of the movable plate and the movable partition is increased. Therefore, the vibration isolation effect by the orifice passage is more effectively exhibited.

  According to a fourth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to third aspects, the movable partition wall and the displacement regulating portion are disposed between opposing surfaces. The non-linear spring is constituted by a non-linear rubber elastic body in which at least a part of the surface on the movable partition wall side and the surface on the displacement regulating portion side has a projecting cross section.

  Here, the projecting section refers to a sectional shape including at least one projecting portion projecting toward the movable partition wall or the displacement restricting portion, and preferably a corrugated or saw-toothed section in which irregularities are repeated. Adopted. According to this aspect, the nonlinear characteristic of the nonlinear spring can be effectively expressed. That is, as a result of the formation of the projecting portion, a recess is formed around the projecting portion, and the relief of the rubber and the free surface are secured in the recess, so that the free surface becomes smaller along with the compression deformation. As a result, the high dynamic spring is nonlinearly realized, and the nonlinear characteristics can be effectively exhibited. The free surface refers to a surface that is not deformed and restrained by contact or fixation with another member such as a metal fitting, and is exposed to the atmosphere or liquid. In addition, by forming the projecting portion, the initial spring of the non-linear spring can be sufficiently softened, and the occurrence of sound and impact caused by the contact of the movable partition can be reduced as much as possible. Further, the durability of the nonlinear rubber elastic body can be improved. Here, more preferably, it is desirable that the nonlinear rubber elastic body is disposed over the entire circumference of the movable partition wall. In this way, the elastic force of the nonlinear rubber elastic body can be exerted on the entire circumference of the movable partition wall, and the displacement of the movable partition wall can be expressed more stably. The entire circumference does not necessarily have to be continuous without being interrupted in the circumferential direction, and may extend in the circumferential direction with some discontinuous portions.

  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, an outer peripheral edge of a case main body that houses the movable plate in the movable partition wall is the support. While being elastically supported by the main body of the partition member through a rubber elastic body, a pressure receiving chamber side annular plate is overlapped and fixed to the pressure receiving chamber side end surface of the partition member main body, and is fixed to the movable partition wall. A pressure receiving chamber side displacement restricting portion that is spaced apart and opposed to the displacement direction pressure receiving chamber side is provided on the pressure receiving chamber side annular plate, and is opposed to the movable partition wall with a distance to the intermediate chamber side in the displacement direction. An intermediate chamber side displacement restricting portion is provided on the partition member main body, and an equilibrium chamber side annular plate is overlapped and fixed to the equilibrium chamber side end surface of the partition member main body. When The outer peripheral edge of the elastic movable film is held at a narrow pressure between the partition member main body and the intermediate chamber is provided between the opposing surfaces of the movable partition wall and the elastic movable film inside the partition member main body. Further, the first orifice passage and the second orifice passage are formed so that the outer peripheral portion of the partition member main body extends in the circumferential direction.

  According to this aspect, the partition member body is provided with the movable partition wall and the elastic movable film, the intermediate chamber is formed in the partition member body, and the first orifice passage and the Since two orifice passages are formed, excellent space efficiency can be obtained. Further, the assembly of the movable partition and the elastic movable film to the second mounting member and the formation of the intermediate chamber, the first orifice passage and the second orifice passage are performed by assembling the partition member to the second mounting member. It can be performed and excellent production efficiency can be obtained.

  According to a sixth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to fifth 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, by supporting the movable partition wall and the elastic movable film on the cylindrical fixing portion, the movable partition wall and the elastic movable film can be easily attached to the partition portions of the intermediate chamber, the pressure receiving chamber, and the intermediate chamber and the equilibrium chamber. It can be disposed and can be easily assembled to the second mounting member.

  According to a seventh aspect of the present invention, in the fluid-filled vibration isolator according to the sixth 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, abnormal noise or vibration generated due to the impact of the movable partition against the displacement restricting portion or the movable plate or the valve element hitting the movable partition. Transmission from the cylindrical fixing portion to the second mounting member can be reduced by an absorbing action based on elastic deformation of the covering rubber layer. That is, the hitting sound and vibration generated between the movable partition wall and the displacement restricting portion can be reduced by the covering rubber layer, and especially the hitting sound and vibration generated between the movable plate or the valve body and the movable partition wall. Can be doubled by the supporting rubber elastic body and the covering rubber layer. Thereby, the further silence and the reduction effect of a vibration can be acquired.

  Further, this aspect is particularly preferably applied to an automobile engine mount, and the first mounting member is fixed to the power unit and the second mounting member is fixed to the vehicle body, and the power unit is fixed to the vehicle body. Anti-vibration support. Under such a mounted state, the vibration energy associated with the impact of the movable partition against the displacement restricting portion when the impact load is input and the impact of the movable plate or valve body against the movable partition is absorbed by the coated rubber layer. Thus, transmission to the second mounting member is reduced. As a result, vibration energy transmitted from the second mounting member to the vehicle body is suppressed, and vibrations and abnormal noise felt by passengers in the vehicle interior 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. As a result, the first dynamic damper including the movable partition wall, the supporting rubber elastic body, and the nonlinear spring, and the second dynamic damper including the partition member and the covering rubber layer are connected in series. A vibration model of the degree system 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.

  An eighth aspect of the present invention is the fluid-filled vibration isolator according to the seventh aspect, wherein the fluid-tight vibration isolator is connected to the outer peripheral portion of the flexible membrane 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 the axial contact rubber is interposed between the partition member and the annular fixing bracket, it is caused by the impact of the movable partition against the displacement restricting portion and the contact of the movable plate or the valve body with the movable partition. The transmission of abnormal noise and vibration generated in the partition member to the annular fixing bracket can be reduced by the axial contact rubber, and the abnormal noise and vibration can be reduced to the second mounting member via the annular fixing bracket. Transmission can also 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 automobile engine mount 10 as a first embodiment according to 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 fixing portion 17 and a flange portion that extends to the outer peripheral side at the upper end edge of the fixing portion 17. 18 is integrally provided. Further, a bolt hole 20 opening upward is formed on the central axis of the first mounting bracket 12, and the first mounting bracket 12 is illustrated by a fixing bolt (not shown) screwed into the bolt hole 20. Not to be fixed to the power unit of the car.

  On the other hand, the second mounting bracket 14 has a large-diameter substantially stepped cylindrical shape, and the upper portion is a large-diameter cylindrical portion 24 across a step portion 22 formed in an axially intermediate portion. On the other hand, the lower portion is a small diameter cylindrical portion 26 having a smaller diameter than the large diameter cylindrical portion 24. The large diameter cylindrical portion 24 and the small diameter cylindrical portion 26 constitute a cylindrical portion of the second mounting bracket 14. Further, the first mounting bracket 12 is spaced apart from the opening side of one of the cylindrical portions of the second mounting bracket 14 (upward in FIG. 1), and the central axes of both the brackets 12 and 14 are substantially on the same line. The main rubber elastic body 16 is disposed between the first mounting bracket 12 and the second mounting bracket 14.

  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 end. A large-diameter recess 28 that opens toward the top is formed. The fixing portion 17 of the first mounting bracket 12 is inserted and vulcanized and bonded to the small-diameter side end of the main rubber elastic body 16, and the large-diameter side end of the main rubber elastic body 16. The outer peripheral surface is overlapped with the inner peripheral surface of the second mounting bracket 14 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 thin seal rubber layer 30 is formed on the inner peripheral surface of the second mounting member 14 as a covering rubber layer that is integrally formed with the main rubber elastic body 16 and extends downward from the opening edge of the large-diameter recess 28. It is deposited. Further, a stepped portion 32 that extends in the direction perpendicular to the axis is formed at the axially intermediate portion of the seal rubber layer 30, and the axially lower portion across the stepped portion 32 is thinner than the axially upward portion.

  In addition, a diaphragm 34 as a flexible film is attached to the integrally vulcanized molded product of the main rubber elastic body 16. The diaphragm 34 is formed of a thin rubber elastic body having a substantially disc shape. The diaphragm 34 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 substantially dome shape. Further, an annular fixing portion 36 is integrally formed on the outer peripheral edge portion of the diaphragm 34, and a large-diameter ring-shaped fixing fitting 38 as an annular fixing fitting is superimposed on the outer peripheral surface of the annular fixing portion 36 and vulcanized. It is glued. Thereby, in this embodiment, the diaphragm 34 is formed as an integral vulcanization molded product provided with the fixing bracket 38.

  The diaphragm 34 is fixed to the second mounting member 14 by the fixing member 38 being inserted into the lower end opening of the second mounting member 14 and being fixed to the caulking part 40. As a result, the opening in the axial direction of the second mounting bracket 14 is covered fluid-tightly by the diaphragm 34, and the main rubber elastic body 16 and the diaphragm 34 that cover both sides in the axial direction of the second mounting bracket 14 are covered. A fluid chamber 42 in which an incompressible fluid is sealed is formed between the axially opposed surfaces.

  The incompressible fluid sealed in the fluid chamber 42 is not particularly limited, but water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixture thereof is preferably used. 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 44 is accommodated in the fluid chamber 42 so as to spread in the direction perpendicular to the axis. The partition member 44 is provided with a movable partition wall 50 supported by a support rubber elastic body 48 in an upper opening portion of a partition member main body 46 as a cylindrical fixing portion having a substantially cylindrical shape, and elastic in a lower opening portion. A movable rubber film 52 as a movable film is provided.

  The partition member body 46 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 stepped portion 54 that protrudes radially inward is formed at a substantially intermediate portion in the axial direction on the inner peripheral surface of the partition member main body 46, and the inner diameter below the upper stepped portion 54 is slightly reduced. In addition, a lower stepped portion 56 protruding radially inward is formed below the upper stepped portion 54, and the inner diameter below the lower stepped portion 56 is further reduced.

  Furthermore, the first circumferential groove 58 and the second circumferential groove 58 open to the outer circumferential surface of the partition member main body 46 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 46. The circumferential grooves 60 are respectively formed. The first circumferential groove 58 and the second circumferential groove 60 are communicated with each other through a connection hole 62 formed in the axial direction of the partition member main body 46 at one end in the circumferential direction. In 46, the first circumferential groove 58 and the second circumferential groove 60 form a circumferential groove extending in the circumferential direction with a length of a little less than two rounds in the circumferential direction. In addition, a first through hole 64 that opens above the partition member main body 46 is formed at the circumferential end on the opposite side of the connection hole 62 in the first circumferential groove 58, while the second circumferential groove 60, a second through-hole 66 that opens below the partition member body 46 is formed at the circumferential end opposite to the connection hole 62. Furthermore, a third through hole 68 that opens to the inner peripheral surface of the partition member main body 46 is formed in a part of the second circumferential groove 60 in the circumferential direction.

  The movable partition wall 50 includes a partition body 70 as a case body and a lid member 72. The partition body 70 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. A communication hole 74 is provided in the thickness direction in the radially outer portion of the bottom wall portion of the partition wall body 70.

  On the other hand, the lid member 72 is formed of a member similar to the partition wall main body 70 and has a substantially disk shape having an outer diameter dimension slightly larger than the outer diameter dimension of the partition wall main body 70. A communication hole 76 is provided in the radially outer portion of the lid member 72 in the thickness direction.

  The lid member 72 is assembled so as to overlap the upper opening end surface of the partition wall main body 70. Although detailed illustration is omitted, for example, the lid member 72 is assembled to the partition wall body 70 by, for example, protruding a caulking portion protruding upward from the partition wall body 70 through the lid member 72 and projecting upward. This is performed by caulking the caulking portion protruding from the lid member 72. Accordingly, the opening of the partition wall body 70 is covered with the lid member 72, and a substantially cylindrical accommodation space 78 extending in the vertical direction with a substantially constant inner diameter dimension is formed inside the movable partition wall 50.

  In this accommodation space 78, a movable plate 80 is accommodated. The movable plate 80 has a substantially disk shape as a whole, and has a structure integrally including a hard portion 82 constituting a deformation restraining region and an outer peripheral elastic portion 84 constituting a deformation allowable region.

  The hard part 82 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 84 is formed of a rubber elastic body, and the outer peripheral elastic portion 84 is formed so as to cover the entire outer surface of the hard portion 82.

  Such a movable plate 80 is accommodated in the accommodating space 78 with a slight gap from the inner peripheral surface of the partition wall main body 70. In the present embodiment, the thickness dimension of the movable plate 80 is slightly smaller than the vertical dimension of the accommodation space 78. As a result, the movable plate 80 is allowed to be slightly displaced in the axial direction within the accommodation space 78. Further, communication holes 74 and 76 are respectively positioned on both the upper and lower sides of the movable plate 80, and the movable plate 80 is formed with an outer diameter dimension capable of covering the communication holes 74 and 76.

  A support rubber elastic body 48 is interposed between the movable partition wall 50 and the partition member main body 46 having such a structure. The support rubber elastic body 48 has a thick annular plate shape as a whole. In particular, the support rubber elastic body 48 in the present embodiment has a stepped portion 86 formed in an intermediate portion in the axial direction (vertical direction in FIG. 1), and the upper part sandwiching the stepped portion 86 has an inner diameter and It is made large in any of the outer diameters. The inner peripheral surface of the support rubber elastic body 48 is vulcanized and bonded to the outer peripheral surface of the partition wall body 70, and the outer peripheral surface is vulcanized and bonded to the inner peripheral surface including the upper step portion 54 of the partition member main body 46. ing.

  Thereby, the support rubber elastic body 48 is formed as an integral vulcanization molded product including the partition wall body 70 and the partition member body 46. At the same time, the movable partition wall 50 and the partition member main body 46 are connected by the support rubber elastic body 48, and the upper opening of the partition member main body 46 is covered with the support rubber elastic body 48 and the movable partition wall 50. The outer peripheral edge of the movable partition wall 50 is elastically supported by the support rubber elastic body 48 with respect to the partition member main body 46, and the movable partition wall 50 is supported by the partition member main body 46 so as to be elastically displaceable in the vertical direction.

  Further, an upper plate 88 as a pressure receiving chamber side annular plate is superimposed and assembled on the upper end surface of the partition member main body 46. The upper plate 88 is formed in a substantially circular plate shape having a central hole 89 formed of a metal such as iron or aluminum alloy or a hard synthetic resin, for example, and the outer diameter of the upper plate 88 is the partition member main body. 46 is slightly smaller than the outer diameter of the upper end face. Further, a positioning protrusion 90 that is substantially cylindrical and protrudes downward in the axial direction (downward in FIG. 1) is bent and formed slightly inside from the outer peripheral edge of the upper plate 88. The outer diameter of the positioning protrusion 90 is slightly smaller than the inner diameter of the partition member body 46 above the upper step 54. An inner peripheral portion 92 that protrudes further inward in the radial direction from the positioning protrusion 90 is formed.

  Such an upper plate 88 is positioned substantially coaxially with the partition member main body 46 by inserting the positioning protrusion 90 into the upper opening of the partition member main body 46, and overlaps the upper end surface of the partition member main body 46. Can be assembled in a combined state. The upper plate 88 may be assembled to the partition member main body 46 by adhesion, welding, or the like, and for example, a twist lock structure as disclosed in Japanese Patent Application Laid-Open No. 2004-144237 may be suitably employed. As a result, the inner peripheral portion 92 positioned radially inward of the positioning projection 90 on the upper plate 88 has a pressure receiving chamber 114 in the displacement direction of the movable partition wall 50 with respect to the outer peripheral portion of the upper end surface of the movable partition wall 50. The pressure receiving chamber side displacement restricting portion is configured by the inner peripheral portion 92 of the upper plate 88 in the present embodiment.

  An upper stopper rubber 94 as a non-linear rubber elastic body is interposed over the entire circumference of the movable partition wall 50 between opposed surfaces of the inner peripheral portion 92 of the upper plate 88 and the movable partition wall 50. The upper stopper rubber 94 has a substantially annular shape that is continuous over the entire circumference. The outer diameter of the upper stopper rubber 94 is substantially equal to the inner diameter of the positioning protrusion 90 of the upper plate 88, while the inner diameter is the upper plate. 88 is slightly larger than the diameter of the central hole 89 and smaller than the outer diameter of the movable partition wall 50.

  As shown in FIG. 2, the upper stopper rubber 94 has a protruding cross section in which a plurality of wavy protrusions 96 are formed in the lower half in the thickness direction (vertical direction in FIG. 2) in the circumferential cross section. ing. 2 corresponds to the II-II cross section in FIG. 1, and is a diagram in which the radial center of the upper stopper rubber 94 is developed in a cross section extending in the circumferential direction. That is, the upper stopper rubber 94 is formed with a plurality of ridges extending radially from the center portion, and each of the ridges is a wave-like protrusion 96. The upper stopper rubber 94 is interposed between the inner peripheral portion 92 of the upper plate 88 and the movable partition wall 50 with the wavy projection 96 protruding downward. Thereby, the surface between the plurality of wave-like projections 96 is a free surface that is free to be deformed and exposed to the liquid without being restrained by contact with or being fixed to another member such as a metal fitting. The stopper rubber 94 is a non-linear spring having a non-linear characteristic in which the support spring rigidity is increased non-linearly as the amount of compression in the thickness direction is increased.

  Further, the lower stepped portion 56 of the partition member main body 46 is spaced apart and opposed to the intermediate chamber 118 side in the displacement direction of the movable partition wall 50. In the present embodiment, the lower stepped portion 56 provides an intermediate position. A chamber side displacement restricting portion is configured. A lower stopper rubber 98 as a nonlinear rubber elastic body is interposed over the entire circumference of the movable partition wall 50 between the outer peripheral portion on the lower surface of the movable partition wall 50 and the lower stepped portion 56.

  The lower stopper rubber 98 is a non-linear spring having the same structure as the upper stopper rubber 94 and provided with non-linear characteristics, and the movable partition wall 50 and the lower side with the wavy protrusion 96 protruding downward. It is interposed between the stepped portions 56.

  Particularly in the present embodiment, the axial separation distance between the movable partition wall 50 and the inner peripheral portion 92 of the upper plate 88 and the lower step portion 56 of the partition member main body 46 in the non-input state of vibration is the upper and lower. The upper and lower side stopper rubbers 94 and 98 are both set to be substantially the same as the thickness of the side stopper rubbers 94 and 98, and the upper and lower side stopper rubbers 94 and 98 are all in a state where no vibration is input to the movable partition wall 50. However, the upper and lower stopper rubbers 94 and 98 may be disposed in a state in which a predetermined pre-compression is applied in consideration of required nonlinear characteristics or the like. The upper and lower stopper rubbers 94 and 98 may be brought into a non-contact state with a gap with respect to the movable partition wall 50 so that the movable partition wall 50 is brought into contact with the upper and lower stopper rubbers 94 and 98 at the time of vibration input. The pre-compression amount of the upper and lower side stopper rubbers 94 and 98 and the separation distance from the movable partition wall 50 are the dimension in the thickness direction of the upper and lower side stopper rubbers 94 and 98, the movable partition wall 50, the inner peripheral portion 92, and the lower step portion 56. It can be adjusted by adjusting the separation distance. The upper and lower stopper rubbers 94.98 may be interposed between the movable partition wall 50 and the upper plate 88 and between the movable partition wall 50 and the lower stepped portion 56 in a non-fixed manner, or It may be fixed to any of the movable partition wall 50, the upper plate 88, and the lower stepped portion 56.

  As is clear from FIG. 2, in the present embodiment, the upper and lower stopper rubbers 94, 98 are all arranged in the same direction with the wave-like protrusion 96 protruding downward. The protrusions 96 are disposed in the same direction with the protrusions projecting upward, and the upper and lower stopper rubbers 94 and 98 are disposed in opposite directions, so that the wavy protrusions 96 face each other or face in opposite directions. Of course, it is also possible to arrange them.

  As described above, the movable partition wall 50 elastically supported by the support rubber elastic body 48 so as to be displaceable in the vertical direction with respect to the partition member body 46 has the inner peripheral portion 92 of the upper plate 88 and the partition member body on both sides in the displacement direction. 46 are respectively opposed to each other, and upper and lower stopper rubbers 94 and 98 having nonlinear characteristics are interposed between the inner peripheral portion 92 and the lower step portion 56, respectively. Thereby, the displacement amount of the movable partition wall 50 is nonlinearly limited on both sides in the displacement direction. In this embodiment, the inner peripheral portion 92 of the upper plate 88 and the lower side of the partition member main body 46 are arranged. A non-linear stopper mechanism is configured including the step portion 56 and the upper and lower stopper rubbers 94 and 98.

  On the other hand, a movable rubber film 52 is disposed in the lower opening of the partition member main body 46. The movable rubber film 52 has a substantially disc shape formed from a rubber elastic body. The outer peripheral edge of the movable rubber film 52 is integrally formed with an outer peripheral fixing portion 100 having a substantially circular cross section that slightly protrudes on both sides in the thickness direction of the movable rubber film 52 and extending over the entire circumference in the circumferential direction. .

  Such a movable rubber film 52 is nipped and fixed between the partition member main body 46 and the lower plate 102 as an equilibrium chamber side annular plate at the lower end portion of the partition member main body 46. Specifically, a lower concave portion 103 opened downward is formed in the central portion of the lower end surface of the partition member main body 46, and the inner diameter of the lower stepped portion 56 is further formed in the central portion of the lower concave portion 103. A fitting recess 104 having a substantially circular concave shape opened downward with a diameter larger than the dimension is formed.

  On the other hand, the lower plate 102 is formed in a substantially circular plate shape having a central hole 106 made of a metal such as iron or aluminum alloy or a hard synthetic resin, for example, and the outer diameter of the lower plate 102 is While the outer diameter dimension of the lower end surface of the partition member body 46 is substantially equal, the inner diameter dimension of the lower plate 102 is substantially equal to the inner diameter dimension of the lower stepped portion 56 in the partition member body 46. Further, a central protrusion 110 protruding upward is formed at the central portion of the lower plate 102, and the central protrusion 110 is supported by a curved groove-like support continuous over the entire circumference. A recess 112 is formed. In a state where the lower plate 102 is overlapped with the lower end surface of the partition member body 46, the central protrusion 110 is inserted into the lower recess 103 of the partition member body 46, and the support recess 112 is fitted into the partition member body 46. In cooperation with the landing recess 104, a space having a substantially circular cross-sectional shape slightly smaller than the outer peripheral fixed portion 100 of the movable rubber film 52 is formed. The lower plate 102 is assembled to the partition member body 46 by adhesion, welding, a twist lock mechanism, or the like, similar to the upper plate 88.

  The movable rubber film 52 is fitted into the fitting recess 104 of the partition member main body 46, and the lower plate 102 is overlapped and fixed to the lower end surface of the partition member main body 46. Thereby, the outer periphery fixing | fixed part 100 of the movable rubber film 52 is clamped by the fitting recessed part 104 and the support recessed part 112 in a compression state. In this manner, the movable rubber film 52 is assembled to the lower end portion of the partition member main body 46 in a state where the elastic deformation of the central portion thereof is allowed, and the downward opening of the partition member main body 46 has a movable rubber film. 52 is fluid-tightly covered. Note that the inner peripheral edge of the lower plate 102 is slightly bent downward, and the biting of the movable rubber film 52 is avoided.

  Here, the spring rigidity of the movable rubber film 52 is to prevent the intermediate chamber 118, which will be described later, from functioning as an equilibrium chamber at the time of vibration input, and to ensure the fluid flow amount of the first orifice passage 120, which will be described later. In addition, it is set larger than at least the spring stiffness of the diaphragm 34. In the present embodiment, since the second orifice passage 122 described later is formed by communicating the pressure receiving chamber 114 and the intermediate chamber 118, more preferably, the fluid flowing through the second orifice passage 122 is fluidized. In order to effectively generate the flow, a small spring stiffness is set to such an extent that it can absorb amplitude vibrations in the middle frequency range of the tuning frequency range of the second orifice passage 122. The spring rigidity of the movable rubber film 52 can be appropriately set by changing the forming material, shape, etc. of the movable rubber film 52.

  The partition member 44 having such a structure is inserted into the small diameter tubular portion 26 of the second mounting bracket 14 from the lower opening, and the upper plate 88 has an upper end surface formed on the seal rubber layer 30. A fixing bracket 38 which is overlapped in the axial direction with respect to the portion 32 and further provided with a diaphragm 34 is inserted into the small diameter cylindrical portion 26, and the outer peripheral edge of the lower surface of the lower plate 102 is placed on the upper end surface of the fixing bracket 38. Superimposed. Thus, the partition member 44 is positioned in the axial direction by being sandwiched between the stepped portion 32 and the fixing bracket 38. Then, the diameter of the second mounting bracket 14 is reduced and the caulking portion 40 is caulked so that the outer peripheral surface of the partition member main body 46 has a small diameter of the second mounting bracket 14 via the seal rubber layer 30. The partition member main body 46 is elastically fitted and supported to the small-diameter cylindrical portion 26 of the second mounting bracket 14 through the seal rubber layer 30 by being pressed against the inner peripheral surface of the cylindrical portion 26. .

  In this manner, the partition member 44 is accommodated and disposed so as to spread in the direction perpendicular to the axis in the fluid chamber 42 with respect to the small-diameter cylindrical portion 26 of the second mounting bracket 14. Divided up and down. Thereby, a part of the wall portion is configured by the main rubber elastic body 16 on the upper side in the axial direction of the partition member 44, and pressure fluctuation is induced based on elastic deformation of the main rubber elastic body 16 at the time of vibration input. On the other hand, a chamber 114 is formed. On the lower side in the axial direction of the partition member 44, a part of the wall portion is constituted by the diaphragm 34, and the volume change due to the deformation of the diaphragm 34 is easily allowed. Is formed. That is, the fluid chamber 42 in which the incompressible fluid is sealed is partitioned into the pressure receiving chamber 114 and the equilibrium chamber 116 by the partition member 44, and the pressure receiving chamber 114 and the equilibrium chamber 116 are sealed with the incompressible fluid. Has been.

  Further, the upper opening of the partition member main body 46 is covered with the movable partition wall 50 and the supporting rubber elastic body 48, and the lower opening is covered with the movable rubber film 52. An intermediate chamber 118 is formed between the opposing surfaces of the movable partition wall 50 and the movable rubber film 52. Thus, the partition between the intermediate chamber 118 and the pressure receiving chamber 114 in the partition member 44 is configured to include the movable partition 50, and the pressure receiving chamber 114 is connected to the upper surface of the movable plate 80 provided in the movable partition 50 through the communication hole 76. On the other hand, the pressure of the intermediate chamber 118 is applied to the lower surface of the movable plate 80 through the communication hole 74. Further, a partition wall portion of the partition member 44 between the intermediate chamber 118 and the equilibrium chamber 116 includes the movable rubber film 52, and the pressure of the intermediate chamber 118 is exerted on the upper surface of the movable rubber film 52, while the movable rubber film The pressure of the equilibrium chamber 116 is exerted on the lower surface of 52.

  Further, the first circumferential groove 58 and the second circumferential groove 60 opened on the outer peripheral surface of the partition member main body 46 are fluid-tightly covered with the seal rubber layer 30. Thereby, the 1st orifice channel | path 120 extended in the outer peripheral part of the partition member 44 by a length of a little less than 2 rounds using the 1st circumferential groove 58 and the 2nd circumferential groove 60 is formed, and the 1st One end in the circumferential direction of the orifice passage 120 is connected to the pressure receiving chamber 114 through a communication hole 121 penetrating the first through hole 64 and the upper plate 88, and the other end is connected to the second end. The pressure receiving chamber 114 and the equilibrium chamber 116 are communicated with each other through the first orifice passage 120 by being connected to the equilibrium chamber 116 through the through hole 66 and the communication hole 123 penetrating the lower plate 102.

  Further, a second orifice passage 122 is formed using the second circumferential groove 60 to extend the outer peripheral portion of the partition member 44 with a length of a little less than one round, and one end in the circumferential direction of the second orifice passage 122 Is connected to the pressure receiving chamber 114 through a communication hole 121 penetrating the first through hole 64 and the upper plate 88, and the other end is connected to the intermediate chamber 118 through the third through hole 68. Thus, the pressure receiving chamber 114 and the intermediate chamber 118 are communicated with each other through the second orifice passage 122. In the present embodiment, the third through hole 68 communicates with the intermediate chamber 118 through the wave-like projections 96 of the lower stopper rubber 98. For example, the lower stopper rubber 98 is circumferentially connected. Alternatively, the third through hole 68 may be communicated with the intermediate chamber 118 through the communication hole as a C-shape having a communication hole in a part thereof.

  As described above, in the present embodiment, the partition wall 44 is provided with the movable partition wall 50 and the movable rubber film 52 so that the region corresponding to the intermediate chamber 118 is formed in the partition member 44, and Since the first and second circumferential grooves 58 and 60 are provided, the partition member 44 is assembled to the second mounting bracket 14 so that the movable partition wall 50 and the movable rubber film 52 are assembled and the intermediate chamber 118 is formed. The second orifice passages 120 and 122 can be formed at the same time, and excellent manufacturing efficiency can be obtained.

  In the present embodiment, the resonance frequency of the fluid that flows through the first orifice passage 120 based on the relative pressure fluctuation generated between the pressure receiving chamber 114 and the equilibrium chamber 116 at the time of vibration input is about 10 Hz. The low frequency engine shake is tuned so as to advantageously exhibit an anti-vibration effect (high damping effect) based on the resonance action of the fluid. Further, the resonance frequency of the fluid that flows through the second orifice passage 122 based on the relative pressure fluctuation generated between the pressure receiving chamber 114 and the intermediate chamber 118 at the time of vibration input depends on the tuning of the first orifice passage 120. It is tuned so as to advantageously exhibit an anti-vibration effect (low dynamic spring effect) based on the resonance action of the fluid, etc., against idling vibration at a medium frequency of about 15 Hz to 30 Hz, which is higher than the frequency. The tuning of the first orifice passage 120 and the second orifice passage 122 is performed by, for example, rigidity of the wall springs of the pressure receiving chamber 114, the equilibrium chamber 116, and the intermediate chamber 118 (the amount of pressure change necessary for changing the unit volume). The pressure fluctuation transmitted through the orifice passages 120 and 122 is generally adjusted by adjusting the passage length and the passage sectional area of each orifice passage 120 and 122 in consideration of the characteristic value corresponding to Can be grasped as the tuning frequency of the orifice passages 120 and 122.

  Furthermore, the movable plate 80 provided in the movable partition wall 50 absorbs pressure fluctuations in the pressure receiving chamber 114 with respect to traveling booming noise in a high frequency range of about 250 Hz to 400 Hz, which is higher than the tuning frequency of the second orifice passage 122. It is tuned so that it can reduce the fluid pressure absorption. Tuning of the movable plate 80 can be performed by adjusting, for example, the forming material and shape of the movable plate 80, the size of the accommodation space 78 that accommodates the movable plate 80, and the like.

  In addition, in the present embodiment, in particular, the movable partition wall 50 is elastically supported by the partition member body 46 via the support rubber elastic body 48 so as to be vertically displaceable, and is vertically By disposing the side stopper rubbers 94 and 98, one sub vibration system (including the movable partition wall 50 as the mass system and the supporting rubber elastic body 48 and the upper and lower side stopper rubbers 94 and 98 as the spring system) is provided. Dynamic damper) is configured. Here, the natural frequency of the movable partition wall 50 is tuned to a traveling booming noise in a high frequency range of about 250 Hz to 400 Hz, which is higher than the tuning frequency of the second orifice passage 122. The natural frequency of the movable partition wall 50 can be tuned by changing the forming material and shape of the movable partition wall 50, the support rubber elastic body 48, and the upper and lower stopper rubbers 94 and 98. In addition to the mass of the movable partition wall 50, the mass component of the dynamic damper constituted by the fluid mass between the movable partition wall 50 and the movable rubber film 52, which is displaced together with the movable partition wall 50, must be considered. As the spring component, not only the spring component of the support rubber elastic body 48 and the upper and lower stopper rubbers 94 and 98 but also the spring component of the movable rubber film 52, the spring component of the pressure receiving chamber 114 and the equilibrium chamber 116 (expansion spring component), and the like. Since it is necessary to take into consideration, tuning of the natural frequency of the movable partition wall 50 is preferably performed while the engine mount 10 is mounted on the power unit. It is carried out.

  In addition, particularly in the present embodiment, the partition member 44 is elastically supported with respect to the small diameter cylindrical portion 26 via the seal rubber layer 30. Thus, another sub-vibration system (dynamic damper) including the partition member 44 as a mass system and the seal rubber layer 30 as a spring system is configured. In the present embodiment, the movable partition wall 50 and the supporting rubber elasticity are configured. A serial two-degree-of-freedom vibration model is realized by the dynamic damper configured including the body 48 and the upper and lower stopper rubbers 94 and 98 and the dynamic damper configured including the partition member 44 and the seal rubber layer 30. Yes. Here, if the natural frequency of the partition member 44 is in a frequency range higher than the tuning frequency of the second orifice passage 122, the natural frequency of the movable partition wall 50 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 44 can be tuned by changing the forming material and the shape of the partition member 44 and the seal rubber layer 30. Preferably, similarly to the movable partition wall 50, the engine mount 10 It is carried out under the condition of mounting on the power unit.

  The engine mount 10 having such a structure is fixed to the power unit-side mounting member using a fixing bolt (not shown) in which the first mounting bracket 12 is screwed into the bolt hole 20, and the second mounting bracket. The 14 small-diameter 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.

  When a low-frequency large-amplitude vibration such as an engine shake is input, the movable partition wall 50 is greatly displaced. On both sides of the movable partition wall 50 in the displacement direction, upper and lower stopper rubbers 94 having nonlinear characteristics, Since 98 is disposed, the rigidity of the support spring is increased and the amount of displacement is limited. At the same time, when a large amplitude vibration is input, the displacement of the movable plate 80 provided in the movable partition wall 50 is also limited. Thereby, the hydraulic pressure absorbing action of the pressure receiving chamber 114 due to the displacement of the movable partition wall 50 and the movable plate 80 hardly occurs. Further, since the resonance frequency of the movable rubber film 52 constituting a part of the wall portion of the intermediate chamber 118 is tuned to a higher frequency range than the tuning frequency of the first orifice passage 120, the movable rubber film 52 The volume change of the intermediate chamber 118 based on the elastic deformation is limited, and the second orifice passage 122 is substantially cut off. As a result, a large pressure fluctuation is effectively induced in the pressure receiving chamber 114, and a relative pressure fluctuation between the pressure receiving chamber 114 and the equilibrium chamber 116 is effectively induced. As a result, a sufficient amount of fluid flow through the first orifice passage 120 can be secured, and an effective anti-vibration effect (high damping effect) against low-frequency large-amplitude vibration such as engine shake is exhibited.

  On the other hand, at the time of inputting medium frequency medium amplitude vibration such as idling vibration, the first orifice passage 120 is substantially clogged, and the pressure fluctuation in the pressure receiving chamber 114 acts on the movable partition wall 50 and the movable plate 80. . When the medium amplitude vibration is input, the movable partition wall 50 and the movable plate 80 are limited in displacement by the upper and lower stopper rubbers 94 and 98 and the displacement of the movable plate 80 is also limited. The hydraulic pressure absorbing action on the pressure receiving chamber 114 due to the displacement of the pressure hardly occurs. At the same time, the volume change of the intermediate chamber 118 is allowed by the elastic deformation of the movable rubber film 52. As a result, fluid flow through the second orifice passage 122 is positively generated between the pressure receiving chamber 114 and the intermediate chamber 118, and the vibration isolation effect (low dynamic spring effect) based on the fluid flow action is effective. Demonstrated.

  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 122 is input, the first orifice passage 120 and the second orifice passage 122 are substantially It becomes clogged. Therefore, in the present embodiment, the volume change of the intermediate chamber 118 is allowed by the elastic deformation of the movable rubber film 52, and the minute displacement of the movable plate 80 is allowed. Therefore, based on the hydraulic pressure absorbing action of the pressure receiving chamber 114 that is exhibited by the minute displacement of the movable plate 80, the intended vibration isolation effect is exhibited.

  Furthermore, when high-frequency small-amplitude vibration is input, the support spring rigidity of the upper and lower stopper rubbers 94.98 is sufficiently small, and the small-amplitude displacement of the movable partition wall 50 is sufficiently allowed. And since the natural frequency of the movable partition 50 is tuned to the frequency range of the high frequency vibration, the effect of absorbing the vibration energy by the resonance action of the dynamic damper including the movable partition 50 is exhibited, The pressure fluctuation in the pressure receiving chamber 114 is released to the equilibrium chamber 116 through the movable rubber film 52. As a result, the vibration damping effect of the dynamic damper and the pressure reducing effect of the pressure receiving chamber 114 exhibit an effective vibration damping effect against high frequency vibration.

  In addition, by providing the movable rubber film 52 on the partition between the intermediate chamber 118 and the equilibrium chamber 116, the volume change of the intermediate chamber 118 is allowed and the displacement of the movable partition 50 is sufficiently secured. Thus, the effect of the dynamic damper including the movable partition wall 50 as the mass member can be effectively exhibited.

  As described above, in this embodiment, a nonlinear stopper mechanism is provided, and the amount of displacement of the movable partition wall 50 is limited when low-frequency large-amplitude vibration or medium-frequency medium-amplitude vibration is input. While effectively exhibiting the effect, it is possible to exhibit an effective dynamic damper effect by allowing the displacement of the movable partition wall 50 when high frequency small amplitude vibration is input. In any case, it is possible to exhibit an effective anti-vibration effect.

  In addition, in this embodiment, the entire partition member 44 is elastically supported with respect to the second mounting member 14 via the seal rubber layer 30, so that the movable partition wall 50, the support rubber elastic body 48, and the partition member 44 are supported. In addition, a series of two-degree-of-freedom vibration model including the seal rubber layer 30 is realized, and it is possible to obtain a better tuning degree of freedom and a damping effect.

  Further, since the movable partition wall 50 provided with the movable plate 80 is elastically supported by the second mounting bracket 14 via the support rubber elastic body 48, the movable plate 80 is moved by the excessive pressure fluctuation or the like, for example. Even if it hits 50 strongly, it is possible to reduce the transmission of the sound and vibration resulting from this to the second mounting bracket 14 by the support rubber elastic body 48. In addition, particularly in the present embodiment, the partition member main body 46 to which the movable partition wall 50 is connected is supported by the second mounting bracket 14 via the seal rubber layer 30. As a result, the transmission of abnormal noise and vibration due to the contact of the movable plate 80 to the movable partition wall 50 to the second mounting bracket 14 can be reduced by the support rubber elastic body 48 and the seal rubber layer 30. It is possible, and more effective noise and vibration reduction effects are exhibited.

  Further, since the upper and lower stopper rubbers 94 and 98 are respectively disposed between the movable partition wall 50 and the inner peripheral portion 92 of the upper plate 88 and the lower step portion 56 of the partition member main body 46, the movable partition wall 50. However, it is also possible to avoid hitting the inner peripheral portion 92 and the lower stepped portion 56 violently, and it is possible to obtain better silence.

  Next, FIG. 3 shows a partition member 130 provided in an engine mount according to a fluid-filled vibration isolator as a second embodiment of the present invention. In this embodiment, since the structure other than the movable partition can adopt the same structure as the engine mount 10 as the first embodiment, the movable partition 132 is provided in FIG. Only the partition member 130 is shown. Moreover, in the following description, about the site | part or member substantially the same as said 1st embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol in a figure.

  In the partition wall main body 134 constituting the movable partition wall 132 in the present embodiment, a cylindrical partition wall portion 138 protruding upward is integrally formed on the concentric shaft at the center portion of the bottom wall portion 136. A plurality of communication holes 74 are provided in the bottom wall 136 in the radial direction outward from the partition wall 138 in the thickness direction, while a plurality of communication holes 74 are provided radially inward from the partition wall 138. A lower central communication hole 140 is provided in the thickness direction. Although not necessarily clear from the drawings, in the present embodiment, the lower central communication hole 140 is concentric with the bottom wall portion 136 and has a predetermined radial width dimension and a circumference slightly smaller than ¼ circumference. The lower center communication hole 140 is formed on the concentric circle of the bottom wall portion 136 at a predetermined interval in the circumferential direction. Thereby, it is possible to make the lower central communication hole 140 closed by the annular rubber plate 150, which will be described later, substantially uniform without any deviation in the circumferential direction.

  On the other hand, a plurality of upper communication holes 76 are provided in the thickness direction on the outer side in the radial direction of the lid member 142 that covers the opening of the partition wall main body 134, while the central portion of the lid member 142 has a circular shape. The upper center communication hole 144 is penetrated in the thickness direction. The diameter dimension of the upper center communication hole 144 is smaller than the inner diameter dimension of the partition wall portion 138 of the partition wall body 134.

  Then, the lid member 142 is assembled so as to overlap the upper opening end surface of the partition wall main body 134, whereby the internal space of the partition wall main body 134 is partitioned by the partition wall portion 138, and the partition wall portion 138 is inside the movable partition wall 132. A first accommodating space 146 having a substantially cylindrical shape extending in the vertical direction and having a substantially constant inner diameter dimension is formed inside, while a first accommodating space 146 is formed outside the partition wall portion 138. A tunnel-like second accommodation space 148 is formed that surrounds and extends in the circumferential direction.

  In the first accommodation space 146, an annular rubber plate 150 as a valve body and a coil spring 152 as an urging means for applying an urging force to the annular rubber plate 150 are accommodated and disposed. The annular rubber plate 150 is formed of a rubber elastic body and has a circular plate shape having a predetermined thickness and a through hole at the center. Furthermore, the outer diameter dimension of the annular rubber plate 150 is larger than the outer diameter dimension of the annular shape formed by the plurality of lower center communication holes 140 extending in an arc shape with a predetermined radial width dimension, The inner diameter of the annular rubber plate 150 is smaller than the inner diameter of the annular shape formed by the plurality of lower center communication holes 140. In short, the annular rubber plate 150 is formed with a size that can cover the entire opening of the plurality of lower center communication holes 140 into the first accommodation space 146.

  On the other hand, the coil spring 152 is preferably made of metal. Further, as the coil spring 152, a coil spring having a constant diameter dimension and extending straight in the axial direction can be adopted. What you have is adopted. Therefore, the diameter dimension of the end portion on the large diameter side of the coil spring 152 is slightly smaller than the inner diameter dimension of the first accommodation space 146. On the other hand, the diameter dimension of the end portion on the small diameter side of the coil spring 152 is larger than the inner diameter dimension of the annular rubber plate 150 and smaller than the outer diameter dimension, and more preferably, a plurality of lower central communication holes. The inner diameter dimension of the annular shape formed by 140 is larger than the outer diameter dimension.

  Then, while the end portion on the large diameter side of the coil spring 152 is overlapped with the lid member 142, the end portion on the small diameter side is overlapped with the annular rubber plate 150, and the annular rubber plate 150 and the coil spring 152 are the first. Thus, the coil spring 152 is compressed between the annular rubber plate 150 and the lid member 142 in the axial direction. As a result, a downward biasing force is exerted on the annular rubber plate 150 by the restoring force of the coil spring 152, and the annular rubber plate 150 is pressed against the bottom wall portion 136 of the partition wall body 134 from above. A lower center communication hole 140 penetrating through 136 is closed from above by an annular rubber plate 150. In particular, in the present embodiment, the end portion on the large diameter side of the coil spring 152 is positioned in the radial direction by the partition wall portion 138, thereby pressing the annular rubber plate 150 at the end portion on the small diameter side of the coil spring 152. Is positioned above the central portion of the lower central communication hole 140.

  As a result, a communication hole that connects the pressure receiving chamber 114 and the equilibrium chamber 116 is formed including the upper central communication hole 144, the lower central communication hole 140, and the first accommodation space 146. The first accommodation space 146 is provided with a one-way valve by an annular rubber plate 150 and a coil spring 152. The annular rubber plate 150 is a first central communication hole 140 that forms a communication hole. Is closed from the opening side of the receiving space 146, in other words, from the opening side of the pressure receiving chamber 114, and the communication hole connecting the pressure receiving chamber 114 and the intermediate chamber 118 is closed by the biasing force of the coil spring 152. It is supposed to do.

  The urging force exerted on the annular rubber plate 150 by the coil spring 152 is a vibration input that causes the operation of the first orifice passage 120 and the second orifice passage 122 and the dynamic damper operation by the movable partition wall 132. Due to the accompanying pressure fluctuation, the annular rubber plate 150 is not separated from the bottom wall portion 136, and the annular rubber plate 150 is separated from the bottom wall portion 136 only when an excessive negative pressure that causes cavitation is generated in the pressure receiving chamber 114. It is preferable that the degree is set.

  On the other hand, the movable plate 154 is accommodated in the second accommodation space 148. The movable plate 154 in the present embodiment has an annular plate shape as a whole with an outer peripheral elastic portion 158 attached and formed so as to wrap the entire outer surface of the hard portion 156 having an annular plate shape, and the partition wall portion. It is accommodated in the second accommodating space 148 so as to be extrapolated with a slight gap with respect to 138.

  According to the present embodiment, 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 114, the pressure receiving chamber. An annular rubber plate 150 disposed between the upper central communication hole 144 and the lower central communication hole 140 communicating with the intermediate chamber 118 and the intermediate chamber 118 resists the urging force of the coil spring 152, and the lower central communication hole 140. Spaced apart from the opening. As a result, the intermediate chamber 118 and the pressure receiving chamber 114 are communicated with each other through the upper central communication hole 144 and the lower central communication hole 140, and the excessive negative pressure in the pressure receiving chamber 114 is quickly eliminated by the inflow of fluid from the intermediate chamber 118. obtain. 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.

  In this case, the annular rubber plate 150 is overlapped from the opening side of the lower central communication hole 140 on the pressure receiving chamber 114 side. The direction in which the positive pressure is exerted is substantially equal. Thus, the annular rubber plate 150 is maintained in a closed state when a positive pressure is applied from the pressure receiving chamber 114, and is a one-way valve that opens only when a negative pressure is applied from the pressure receiving chamber 114. Yes. Therefore, when a positive pressure is applied from the pressure receiving chamber 114, the closed state of the lower central communication hole 140 is maintained at a high level, and the relative pressure fluctuation between the pressure receiving chamber 114 and the equilibrium chamber 116 is effective. Induced. Then, by applying the positive pressure of the pressure receiving chamber 114 to the annular rubber plate 150, the closed state of the lower center communication hole 140 can be maintained more firmly. Further, since the annular rubber plate 150 is formed of a rubber elastic body, the closed state of the lower central communication hole 140 is expressed more stably, and the hitting sound against the movable partition wall 132 during the closing operation is also generated. It is reduced.

  In addition, the urging force of the coil spring 152 is such that the annular rubber plate 150 is separated from the opening of the lower central communication hole 140 only when an excessive negative pressure is generated to such an extent that cavitation can occur in the pressure receiving chamber 114. The size is set. Therefore, when the vibration is input to such an extent that the dynamic damper including the first orifice passage 120, the second orifice passage 122, and the movable partition wall 132 is activated, the lower central communication hole 140 is closed. Maintained. Thereby, generation | occurrence | production of noise and a vibration can be suppressed, ensuring the vibration proofing effect by these orifice passages 120 and 122 and a dynamic damper effectively.

  Further, particularly in the present embodiment, the pressing position on the annular rubber plate 150 at the end portion on the small diameter side of the coil spring 152 is located above the central portion of the lower central communication hole 140. As a result, the closed state of the lower central communication hole 140 by the annular rubber plate 150 can be expressed more stably, and the lower central communication hole 140 is opened by elastic deformation of the annular rubber plate 150 itself. The risk of being lost is also reduced. Therefore, particularly in the present embodiment, by using a coil spring having a taper shape as the coil spring 152, the end portion on the large diameter side is used as the partition wall portion 138 constituting the peripheral wall of the first accommodation space 146. Can be positioned 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 150 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 152 is also suppressed. As a result, the positional deviation of the pressing position on the annular rubber plate 150 at the end portion on the small diameter side can be advantageously reduced. Further, since the outer diameter dimension of the annular rubber plate 150 is slightly smaller than the inner diameter dimension of the partition wall portion 138, the partition wall portion 138 constitutes a vertical guide structure for the annular rubber plate 150. In addition, the operation of the annular rubber plate 150 can be expressed more stably, the radial displacement of the annular rubber plate 150 is suppressed, and the possibility that the annular rubber plate 150 is detached from the lower central communication hole 140 is also avoided. Has been.

  Next, FIG. 4 shows an engine mount 170 as a third embodiment of the present invention. In the present embodiment, the fixing bracket 172 as an annular fixing bracket connected to the outer peripheral portion of the diaphragm 34 has a shallow, substantially bottomed cylindrical shape as a whole. And the center part of the bottom part of the fixed metal fitting 172 is made to protrude slightly upwards, and the through-hole 174 penetrated in the thickness direction is further formed in the center part. Here, the diameter dimension of the through hole 174 is smaller than the diameter dimension of the lower end surface of the partition member 44, specifically, the lower end surface of the lower plate 102. An annular fixing portion 176 formed on the outer peripheral edge of the diaphragm 34 is vulcanized and bonded so as to cover the entire fixing bracket 172. Accordingly, the inner diameter dimension of the annular fixing portion 176 is made smaller than the diameter dimension of the lower end surface of the partition member 44.

  In addition, the small diameter cylinder part 26 of the 2nd attachment metal fitting 14 in this embodiment is diameter-expanded slightly from the positioning step part 178 formed in the lower end part. Then, the fixing bracket 172 is inserted from the lower end opening of the small diameter cylindrical portion 26 to a position where the upper end surface of the annular fixing portion 176 is locked by the positioning stepped portion 178. The fixing fitting 172 is fitted and fixed to the small diameter cylindrical portion 26 by being caulked and fixed by the caulking portion 40.

  In such an assembled state, an annular fixing portion 176 that covers the fixing bracket 172 is interposed between the lower end surface of the partition member 44 and the fixing bracket 172. In the present embodiment, the annular fixing portion 176 causes an axial contact. A rubber contact is formed. The partition member main body 46 of the partition member 44 has an upper end surface abutted against the stepped portion 32 of the main rubber elastic body 16 via the upper plate 88, while a lower end surface is annular via the lower plate 102. It is brought into contact with the upper end surface of the fixing portion 176 and is elastically supported in the axial direction between the stepped portion 32 and the annular fixing portion 176. In particular, in the present embodiment, since the fixing bracket 172 is positioned below the partition member 44 in the axial direction, the shape of the annular fixing portion 176 can be stably held, and the partition member 44 can be more stably maintained. It is possible to support. In the present embodiment, the seal rubber layer 30 extends to reach the positioning step portion 178, and the ring between the outer peripheral surface of the fixing bracket 172 and the small-diameter cylindrical portion 26 wraps around the outer periphery of the fixing bracket 172. It is fluid-tightly sealed with a fixing portion 176.

  According to the present embodiment, the elastic support characteristic of the partition member 44 is adjusted by adjusting the elasticity of the rubber elastic body constituting the annular fixing portion 176 as the axial contact rubber, the shape and size of the annular fixing portion 176, and the like. And the degree of freedom of adjustment of the dynamic damper including the partition member 44 as a mass member can be further increased.

  Further, since the annular fixing portion 176 is interposed between the partition member 44 and the fixing bracket 172, the annular fixing portion 176 absorbs abnormal noise and vibration caused by the movable plate 80 striking against the movable partition wall 50. Thus, the transmission of the abnormal sound and vibration from the partition member 44 to the second mounting bracket 14 via the fixing bracket 172 can be further reduced.

  In particular, in the present embodiment, by forming the axial contact rubber using the annular fixing portion 176 formed integrally with the diaphragm 34, the number of parts can be reduced and the number of assembling steps can be reduced.

  FIG. 5 shows an engine mount 190 as a fourth embodiment of the present invention. In this embodiment, the integral vulcanization molded product provided with the partition member 44 and the fixing bracket 38 is disposed at a predetermined distance in the axial direction, and specifically, the lower end surface of the partition member 44, A protruding piece 192 as an axial contact rubber is interposed between the lower end surface of the lower plate 102 and the upper surface of the fixing metal 38. The protruding piece 192 is integrally formed with the seal rubber layer 30 so as to protrude radially inward. Accordingly, the protruding piece portion 192 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 44. In particular, in the present embodiment, the protruding piece portion 192 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 38.

  The protruding piece 192 is inserted from the lower end opening of the small-diameter cylindrical portion 26 with the partition member 44 and the fixing metal 38 spaced apart from each other by a predetermined distance in the axial direction, and the small-diameter cylindrical portion 26 is reduced in diameter. Thus, as a result of the partition member 44 and the fixing metal member 38 biting into the seal rubber layer 30, the seal rubber layer 30 is protruded radially inward between the partition member 44 and the fixing metal member 38.

  The protruding piece portion 192 is formed between the partition member 44 and the fixing bracket 38 by the diameter reducing process, with the inner peripheral surface of the seal rubber layer 30 before the diameter reducing process is performed on the small diameter cylindrical part 26 as a flat surface. Although it may be formed by the seal rubber layer 30 biting inward in the radial direction, in particular in the present embodiment, before the diameter reducing process is performed on the small diameter cylindrical portion 26, a partition is previously formed on the inner peripheral surface of the seal rubber layer 30. Positioning grooves 194 and 194 are formed at positions where the member 44 and the fixing bracket 38 bite, respectively, and a protruding piece that is a protruding piece portion 192 is formed between the positioning grooves 194 and 194. The small diameter cylindrical portion 26 is subjected to diameter reduction processing so that the partitioning member 44 and the fixing bracket 38 are fitted in the positioning concave grooves 194 and 194, respectively, and the protruding pieces between the positioning concave grooves 194 and 194 are separated from the partitioning member 44. The protruding piece 192 is formed by protruding further inward in the radial direction between the fixing bracket 38 and the fixing bracket 38. In this way, the protruding piece 192 can be formed with higher accuracy, and the positioning of the partition member 44 and the fixing bracket 38 is facilitated.

  In this manner, the protruding piece 192 is interposed between the partition member 44 and the fixing bracket 38, and the partition member main body 46 of the partition member 44 is connected to the main rubber elastic body via the upper and lower plates 88 and 102. The sixteen step portions 32 and the protruding piece portions 192 are elastically supported in the axial direction. Also in the present embodiment, the elastic support characteristics of the partition member 44 can be adjusted by adjusting the member elasticity, shape, size, and the like of the protruding piece portion 192, and the movable plate 80 strikes the movable partition wall 50 strongly. Abnormal noise and vibration caused by hitting can be absorbed by the protruding piece 192. Also in the present embodiment, the projecting piece 192 as the axial contact rubber is integrally formed with the seal rubber layer 30, so that the number of parts and assembly man-hours can be reduced.

  In FIG. 6, the engine mount 10 having the structure according to the first embodiment is used as an example, and the upper plate 88 and the upper and lower stopper rubbers 94 and 98 constituting the nonlinear stopper mechanism from the engine mount 10 are shown. As a comparative example according to the conventional structure with the removed one, the results of measuring the anti-vibration characteristics of these examples and comparative examples by varying the frequency of the input vibration are shown. 6A shows a damping coefficient when a low frequency vibration having an amplitude of 0.5 mm is input, and FIG. 6B shows a dynamic coefficient when a vibration in the middle frequency region having an amplitude of 0.05 mm is input. It is the result of measuring the static spring constant.

  From FIG. 6 (a), it can be confirmed that according to the embodiment having the structure according to the present invention, a more excellent attenuation effect can be obtained compared with the comparative example in the frequency range of about 10 Hz corresponding to the engine shake. . Further, from FIG. 6B, according to the example, in a frequency range of about 15 Hz to 30 Hz corresponding to idling vibration, the low dynamic spring is superior to the comparative example and at least substantially the same as the comparative example. It can be confirmed that the effect is exhibited.

  As described above, according to the fluid-filled vibration isolator having a structure according to the present invention, it was confirmed that a more excellent vibration isolating effect was exhibited against vibrations in a plurality of frequency ranges.

  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, in the first embodiment, the second orifice passage 122 is formed by communicating the pressure receiving chamber 114 and the intermediate chamber 118, but the second orifice passage 122 is connected to the intermediate chamber 118 and the equilibrium chamber 116. You may form in communication. In such a case, the spring rigidity of the movable rubber film 52 is set in the tuning frequency range of the second orifice passage 122 in order to effectively cause the relative pressure fluctuation between the intermediate chamber 118 and the equilibrium chamber 116. It is preferable that a large spring rigidity is set to such an extent that amplitude vibration in the frequency is not absorbed.

  Further, as the non-linear spring constituting the non-linear stopper mechanism, it is possible to adopt not only a rubber elastic body but also a non-linear metal spring such as an unequal pitch coil spring. Further, the specific shape of the non-linear rubber elastic body is not limited to the shape as in the above-described embodiment. For example, the nonlinear rubber elastic body is formed with a sharper sawtooth-shaped cross section as compared with the first embodiment. Alternatively, the protruding amount and pitch of the protrusions can be made smaller or larger. Further, as described above, the pre-compression amount of the non-linear spring can be appropriately set in consideration of the required non-linear characteristics and the like. For example, as shown in FIG. In addition, the lower stopper rubber 98 is fixed to the lower surface of the movable partition wall 50, and in the non-input state of vibration, between the upper stopper rubber 94 and the movable partition wall 50 and between the lower stopper rubber 98 and the lower stepped portion. The upper and lower stopper rubbers 94 and 98 may be prevented from being pre-compressed so as to be in a non-contact state in which a gap is formed between each of the upper and lower 56.

  Furthermore, the displacement restricting portion is not necessarily fixed to the partition member or formed integrally with the partition member. For example, in the first embodiment, the upper plate 88 that constitutes the displacement restricting portion is overlapped with the partition member body 46 in a non-fixed manner, and between the partition member body 46 and the step portion 32 of the seal rubber layer 30. It may be nipped and fixed.

  Further, in the second embodiment, the annular rubber plate 150 and the coil spring 152 constituting the one-way valve are not necessarily required, but the biasing means of the valve body is not necessarily limited to a metal coil spring. Instead, for example, rubber, elastic synthetic resin, or a leaf spring 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.

  In addition, the movable plates 80 and 154 in each of the above embodiments are all arranged with a slight gap with respect to the inner surface of the accommodation area and can be slightly displaced in the thickness direction. The outer peripheral elastic portion 84 can be made to contact the inner surface of the housing area by forming the outer peripheral elastic portion 84 thicker or by integrally forming an elastic protrusion protruding in the thickness direction on the outer peripheral elastic portion 84. Alternatively, it may be accommodated in the accommodating region in a pre-compressed state, and a minute displacement may be allowed based on the elasticity of the outer peripheral elastic portion 84 itself.

  Furthermore, the dynamic damper configuration using the partition member 44 and the seal rubber layer 30 in each of the above embodiments is not necessarily required. For example, the natural frequency of the partition member 44 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 44 does not substantially function as a dynamic damper.

  Further, in the third embodiment, an annular fixing portion 176 as an axial contact rubber is formed integrally with the diaphragm 34, whereas in the fourth embodiment, a protrusion as an axial contact rubber. The piece 192 is integrally formed with the seal rubber layer 30, but the axial contact rubber does not necessarily have to be formed integrally with the flexible membrane, the main rubber elastic body, etc. Of course, it is also possible to form with a member. For example, in the engine mount 190 according to the fourth embodiment, instead of the projecting piece 192, a rubber elastic body formed as a single piece with an annular plate shape is used as the axial contact rubber, and between the partition member 44 and the fixing bracket 38. It may be interposed between the two.

  Furthermore, a displacement amount limiting mechanism for limiting the displacement amount of the movable rubber film 52 may be provided in order to avoid damage due to excessive displacement of the movable rubber film 52 as the elastic movable film in the embodiment. Such a displacement amount limiting mechanism, for example, is brought into contact with both sides of the movable rubber film 52 in the displacement direction when the movable rubber film 52 is excessively displaced to limit the excessive displacement of the movable rubber film 52. 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. It is a principal part expansion longitudinal cross-section model figure of the engine mount, Comprising: The cross-section model figure equivalent to the II-II cross section of FIG. The longitudinal cross-sectional view of the partition member which comprises 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 vibration proof characteristic of the fluid enclosure type vibration proof device made into the structure according to this invention. The principal part expansion longitudinal cross-section model figure equivalent to FIG. 2 for demonstrating the different aspect of a nonlinear spring.

Explanation of symbols

10: engine mount, 12: first mounting bracket, 14: second mounting bracket, 16: main rubber elastic body, 34: diaphragm, 42: fluid chamber, 44: partition member, 46: partition member body, 48: Support rubber elastic body, 50: movable partition, 52: movable rubber film, 54: upper stepped portion, 56: lower stepped portion, 80: movable plate, 88: upper plate, 92: inner peripheral portion, 94: upper stopper rubber 96: Wavy protrusion, 98: Lower stopper rubber, 114: Pressure receiving chamber, 116: Equilibrium chamber, 118: Intermediate chamber, 120: First orifice passage, 122: Second orifice passage

Claims (8)

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 elastic displacement is allowed, and the partition portion between the intermediate chamber and the equilibrium chamber of the partition member is configured by an elastic movable film, Further, a movable plate with a limited displacement 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 either the pressure receiving chamber or the equilibrium chamber, and the second orifice passage is tuned to a higher frequency range than the first orifice passage, and the support Supported by rubber elastic A dynamic damper is configured by tuning the natural frequency of the movable partition wall to a higher frequency range than the second orifice passage, and a pair of displacement controls that are opposed to both sides of the movable partition wall in the displacement direction. Provided with a non-linear stopper mechanism that non-linearly regulates the amount of displacement of the movable bulkhead on both sides in the displacement direction by interposing a non-linear spring between the movable bulkhead and the pair of displacement regulating portions. A fluid-filled vibration damping device.   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.   One of the first attachment member and the second attachment member is attached to a power unit of an automobile and the other is attached to a vehicle body so as to constitute an automobile engine mount, and the first orifice passage is an engine shake. And the second orifice passage is tuned to an intermediate frequency range corresponding to idling vibration, while the liquid with respect to the pressure receiving chamber based on displacement or deformation of the movable plate is tuned. The pressure absorbing action is expressed in a high frequency range corresponding to a traveling booming noise, and the natural frequency of the movable partition is tuned to a high frequency range corresponding to a traveling booming noise. The fluid-filled vibration isolator described in 1.   A non-linear rubber elastic body disposed between opposing surfaces of the movable partition wall and the displacement regulating portion, wherein at least a part of the movable partition side surface and the displacement regulating portion side surface has a projecting cross section. The fluid-filled type vibration damping device according to claim 1, wherein the nonlinear spring is configured by.   In the movable partition wall, the outer peripheral edge of the case main body that accommodates the movable plate is elastically supported by the main body of the partition member via the support rubber elastic body, while the pressure receiving chamber side end surface of the partition member main body is The pressure receiving chamber side annular plate is overlapped and fixed, and a pressure receiving chamber side displacement restricting portion is provided on the pressure receiving chamber side annular plate and is opposed to the movable partition wall in the displacement direction pressure receiving chamber side. The partition member body is provided with an intermediate chamber side displacement restricting portion that is opposed to the movable partition wall in the displacement direction toward the intermediate chamber side. The chamber-side annular plate is overlapped and fixed, and the outer peripheral edge of the elastic movable film is held at a narrow pressure between the equilibrium chamber-side annular plate and the partition member body. Inside, the intermediate chamber is formed between the opposed surfaces of the movable partition wall and the elastic movable film, and the first orifice passage is extended so that the outer peripheral portion of the partition member body extends in the circumferential direction. And the fluid-filled vibration isolator according to any one of claims 1 to 4, wherein the second orifice passage is formed.   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 6, 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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