JP5243863B2 - Fluid filled vibration isolator - Google Patents

Description

  The present invention relates to a fluid filled type vibration damping device that utilizes a vibration damping effect based on the flow action of an incompressible fluid sealed inside.

  Conventionally, as a type of a vibration isolator such as a vibration isolator coupling body and a vibration isolator support member interposed between members constituting a vibration transmission system, the first mounting member and the second mounting member are formed as a main rubber elastic body. The anti-vibration device connected in the above is known, and a fluid-filled anti-vibration device is known as an advanced type of the anti-vibration device. This fluid filled type vibration damping device forms a pressure receiving chamber in which a part of the wall is made of a main rubber elastic body and an equilibrium chamber in which a part of the wall is made of a flexible film. An incompressible fluid is enclosed, and the two chambers communicate with each other through an orifice passage. According to such a structure, vibration is input to the pressure receiving chamber, and a vibration isolation effect can be exhibited by a flow action such as a resonance action of a fluid flowing through the orifice passage due to a pressure difference between the pressure receiving chamber and the equilibrium chamber. Such a fluid-filled vibration isolator has been studied for application to, for example, an automobile engine mount, body mount, differential mount, suspension member mount, suspension bushing, and the like.

  By the way, in an engine mount for automobiles and the like, an anti-vibration effect is required for vibrations in a plurality of frequency ranges. Therefore, in general, the orifice passage is tuned to low-frequency large-amplitude vibrations such as engine shakes, and high-frequency small-amplitude vibrations such as running-up noise are handled by providing a movable membrane that absorbs pressure fluctuations in the pressure receiving chamber. doing.

  In addition, in engine mounts for automobiles and the like, in recent years, generation of vibration and abnormal noise has been regarded as a problem when an excessive vibration load or impact load is input. This is considered to be mainly due to cavitation bubbles accompanying excessive negative pressure in the pressure receiving chamber. That is, when a vibration having a large amplitude is input and the pressure receiving chamber becomes an excessively negative pressure state, the air dissolved in the fluid in the pressure receiving chamber undergoes liquid phase separation to form cavitation bubbles. Then, the water hammer pressure accompanying the collapse of the bubbles propagates to the first mounting member and the second mounting member, and is transmitted to the members constituting the vibration transmission system such as the automobile body. Sound and vibration are considered to occur.

  In order to cope with such a problem, the present applicant previously described in Patent Document 1 (Japanese Patent Application No. 2007-311749) provided a communication path that connects both chambers to a partition member that divides the pressure receiving chamber and the equilibrium chamber. A novel structure has been proposed in which a closing rubber elastic plate that closes the communication path by overlapping the passage from the pressure-receiving chamber side is provided to configure communication path blocking / blocking control means. When a sudden pressure drop occurs in the pressure receiving chamber when an excessive vibration load or impact load is input, the closed rubber elastic plate elastically deforms and separates from the partition member, so that the communication path is in communication, and the pressure receiving chamber and the equilibrium chamber By short-circuiting, generation of negative pressure in the pressure receiving chamber can be avoided. Further, the closed rubber elastic plate can also exhibit an anti-vibration effect against high-frequency small-amplitude vibrations by exhibiting a function of absorbing pressure fluctuations in the pressure receiving chamber by elastic deformation under the condition that the communication path is blocked.

  Here, the present inventor has made further studies on the fluid-filled vibration isolator described in Patent Document 1, and has conceived that there is still room for improvement. That is, in the communication / blocking control means described in Patent Document 1, when a vibration such as an engine shake is input, the closing rubber elastic plate covering the communication path is elastically deformed based on the pressure difference exerted on both the front and back surfaces. The pressure in the pressure receiving chamber is absorbed along with the elastic deformation. For this reason, the amount of fluid flow through the orifice passage is reduced, and there is a possibility that the anti-vibration effect against the low-frequency large-amplitude vibration by the orifice passage is not sufficiently exhibited.

  In order to cope with this, it is conceivable to increase the deformation rigidity of the elastic rubber plate, but in that case, the pressure fluctuation in the pressure receiving chamber will not be reduced when high-frequency small-amplitude vibration such as traveling noise is input, and high-frequency There arises a problem that the anti-vibration performance against the small amplitude vibration is lowered.

  In short, in the fluid-filled vibration isolator disclosed in Patent Document 1, (i) the anti-vibration effect against low-frequency large-amplitude vibration caused by the orifice passage, and (ii) high-frequency small-amplitude vibration caused by elastic deformation of the closed rubber elastic plate While satisfying both the vibration isolation effect and (iii) suppressing the generation of shocks and abnormal noise caused by pressure fluctuations in the pressure receiving chamber due to excessive vibration input, the requirements are still not fully satisfied. There was a case.

Japanese Patent Application No. 2007-311749

  Here, the present invention has been made in the background as described above, and the problem to be solved is (i) a sufficient anti-vibration effect against low-frequency large-amplitude vibration caused by the orifice passage. On the other hand, the prior application (Patent Document 1) can achieve more effectively the effect of (ii) improving the anti-vibration effect against high-frequency small-amplitude vibration, and (iii) the effect of suppressing the impact and abnormal noise when excessive vibration is input. It is an object of the present invention to provide a fluid-filled vibration isolator having a further improved structure.

  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 and technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an inventive concept that can be grasped by those skilled in the art from those descriptions. It should be understood that this is recognized on the basis of

That is, a feature of the present invention is that the first mounting member and the second mounting member are connected by the 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, An orifice that forms an equilibrium chamber in which a part of the wall is made of a flexible membrane, encloses the incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and communicates the pressure receiving chamber and the equilibrium chamber with each other In the fluid-filled vibration isolator provided with a passage, the partition member that partitions the pressure receiving chamber and the equilibrium chamber forms a communication port that communicates the pressure receiving chamber and the equilibrium chamber, and the pressure receiving pressure with respect to the communication port A closing rubber elastic plate that is overlapped from the chamber side and closes the communication port and opens based on elastic deformation, and the pressure of the pressure receiving chamber is applied to one surface of the closing rubber elastic plate and the other The pressure of the equilibrium chamber is exerted on the surface through the communication port While in, the abutment retaining portion which is constantly held in superposition state against partition member at the outer peripheral edge of the closure rubber elastic plate providing a plurality on the circumference, corresponding adjacent in the circumferential direction of the closure rubber elastic plate The pressure receiving chamber is elastically deformed based on the pressure difference between the pressure receiving chamber and the equilibrium chamber between the contact holding portions and separated from the partition member, thereby opening the communication port and the pressure receiving chamber through the communication port. An elastic deformation region that allows fluid flow to and from the equilibrium chamber is formed, and the elastic characteristics in the elastic deformation region provided on the outer peripheral edge of the closed rubber elastic plate are set to be nonlinear in the elastic deformation region. The fluid-filled vibration isolator is provided with non-linearization means for making the elastic characteristics non-linearly harder as the amount of elastic deformation increases.

  In such a fluid-filled vibration isolator having a structure according to the present invention, there is provided a non-linear means for making the elastic characteristics non-linearly harder as the elastic deformation amount in the elastic deformation region of the closed rubber elastic plate increases. It has been. Non-linear here means that the increase in the spring constant with respect to the increase in the amount of deformation in the elastic deformation region changes more than the proportional relationship. The change mode is not particularly limited, and in addition to a sudden change from a certain amount of change to a polygonal line, it changes to a two-dimensional or multi-dimensional function, or changes in stages in multiple steps. Including.

  Therefore, when a small amplitude vibration with a small pressure difference variation applied to the front and back surfaces of the closing rubber elastic plate is input, the elastic deformation region is elastically deformed relatively easily due to the relatively soft spring characteristic of the closing rubber elastic plate. . Thereby, the pressure absorption effect of the pressure receiving chamber is exhibited based on the elastic deformation action of the closed rubber elastic plate, and the vibration isolation effect against the high frequency small amplitude vibration can be effectively exhibited. In some cases, the closing rubber elastic plate is separated from the partition member and the communication passage is opened, and the same effect is exhibited based on the short-circuiting action between the pressure receiving chamber and the equilibrium chamber.

  On the other hand, when the fluctuation of the pressure difference exerted on both the front and back surfaces of the closed rubber elastic plate is large and the low frequency large amplitude vibration in the tuning frequency range of the orifice passage is input, the spring characteristics in the elastic deformation region of the closed rubber elastic plate are nonlinear. Deformation increases to a region where it suddenly becomes harder, and further elastic deformation and the opening of the communication passage accompanying such elastic deformation are suppressed. As a result, pressure leakage through the communication port in the pressure receiving chamber is suppressed, pressure fluctuation in the pressure receiving chamber is effectively generated, and a sufficient amount of fluid flow through the orifice passage is ensured, and fluid resonance in the orifice passage is achieved. An anti-vibration effect based on a fluid action such as an action can be effectively exhibited.

  Further, when an excessive or shocking vibration load is input and the pressure in the pressure receiving chamber is remarkably lowered, even if the spring characteristics are nonlinearly hardened in the elastic deformation region of the closed rubber elastic plate, the closed rubber elastic plate is Sufficient pressure to be deformed will be exerted on the elastic deformation region. As a result, a large elastic deformation occurs in the entire elastic deformation region, the communication port is greatly opened, and the pressure receiving chamber and the equilibrium chamber are short-circuited. Thereby, generation | occurrence | production of the excessive negative pressure in a pressure receiving chamber is avoided thru | or eliminated rapidly, and generation | occurrence | production of the abnormal sound considered that it originates in cavitation and a vibration can be prevented.

  Therefore, in the fluid-filled vibration isolator having the structure according to the present invention, the above-mentioned (i) securing of the anti-vibration effect against the low-frequency large-amplitude vibration by the orifice passage, and (ii) the anti-vibration effect against the high-frequency small-amplitude vibration. And (iii) the effect of suppressing impact and abnormal noise at the time of excessive vibration input can be effectively achieved.

  In the fluid filled type vibration damping device of the present invention, a central mounting portion is integrally formed at a central portion of the closing rubber elastic plate, and the central mounting portion is fixedly attached to the partition member. On the other hand, a spoke-shaped holding portion that extends radially from the central mounting portion toward the outer peripheral side is provided, and the abutting holding portion is provided so as to extend in the circumferential direction from the tip portion of the spoke-shaped holding portion. The aspect which is may be employ | adopted. According to this aspect, the fixing force of the central mounting portion to the partition member is transmitted as a contact holding force to each contact holding portion via the plurality of spoke-like holding portions, and the closing rubber elastic plate The contact state of the outer peripheral edge with the partition member can be effectively maintained.

  In the fluid-filled vibration isolator of the present invention, the abutment holding portion is constituted by a thick rubber portion, and a pressure holding member is provided on the opposite side of the partition member across the thick rubber portion. The thick rubber portion is pressed against the partition member by the pressure holding member and is elastically held between the elastic members, and the elastic deformation region is located between the thick rubber portions in the circumferential direction. Is made thinner than the thick rubber part, and the thickness dimension of the elastic deformation region is gradually or gradually decreased from the thick rubber part on both sides in the circumferential direction toward the central part in the circumferential direction. An aspect in which the non-linearization means is configured by changing may be adopted.

  In the fluid filled type vibration damping device of the present invention, a reinforcing member harder than the rubber elastic body is fixed to the outer peripheral edge of the closed rubber elastic plate, and the contact holding portion is configured by the reinforcing member. In addition, the elastic deformation region positioned between the contact holding portions in the circumferential direction is easily deformed without the reinforcing member being fixed, while the reinforcing member is moved from the contact holding portion to the elastic deformation region. It extends in the circumferential direction toward the extension holding portion having a rigidity lower than that of the corresponding holding portion, and the extension holding portion causes the elastic characteristics on both sides in the circumferential direction of the elastic deformation region to be higher than those in the circumferential central portion. An aspect in which the non-linearization means is configured by being hardened may be employed.

  In these two aspects, in the elastic deformation region of the closing rubber elastic plate, a soft spring characteristic region is formed in the central portion in the circumferential direction, and relatively hard spring characteristic regions are formed on both sides in the circumferential direction. It becomes.

  Further, in the fluid filled type vibration damping device of the present invention, a pressure receiving chamber side cover member that covers the elastic deformation region of the closed rubber elastic plate separately from the pressure receiving chamber side is provided, and the elastic deformation region and The opposing surface of the pressure-receiving chamber side cover member is provided with an opposing abutting protrusion that protrudes from one side to the other and that has a tip portion facing the other side at a predetermined distance, the elastic deformation region An embodiment may be employed in which the non-linearization means is configured by elastically deforming and separating from the partition member and the opposing abutting protrusion abutting against the other.

  According to such an aspect, in addition to the setting of the shape, size, structure, etc. of the closed rubber elastic plate, the elastic deformation region is also determined by the setting of the shape, size, structure, number, arrangement, etc. of the opposing abutment protrusion The non-linearity of the elastic properties can be adjusted.

  In the fluid filled type vibration damping device of the present invention, a pressure receiving chamber side cover member that covers the closed rubber elastic plate separately from the pressure receiving chamber side is provided, and the pressure receiving chamber side cover member includes A communication hole for connecting an internal region between the pressure receiving chamber side cover member and the closing rubber elastic plate to the pressure receiving chamber is provided at a position away from a portion facing the elastic deformation region of the closing rubber elastic plate. Aspects may be employed.

  According to such an aspect, when the communication port opens in the overpressure state of the pressure-receiving chamber in association with the deformation of the elastic deformation region of the closing rubber elastic plate, when the bubble is generated near the opening, the bubble is released from the inner region. It flows to the pressure receiving chamber through the communication hole. At that time, the bubbles come into contact with the cover member, so that the growth of the bubbles can be suppressed or the bubbles can be subdivided. Therefore, abnormal noise and vibration caused by water hammer pressure accompanying the collapse of large bubbles can be suppressed.

  Further, in the fluid filled type vibration damping device of the present invention, the closing rubber elastic plate is disposed so as to overlap the central portion of the partition member, while the outer peripheral portion of the partition member extends in the circumferential direction. A mode in which the orifice passage is formed may be adopted. According to such an aspect, both the area of the closed rubber elastic plate and the passage length of the orifice passage are ensured to be large, and the intended vibration isolation performance and cavitation prevention effect can be obtained efficiently.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings. First, FIG. 1 shows an automotive engine mount 10 as a first embodiment relating to a fluid filled type vibration damping device of the present invention. The automobile 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 connected to each other by a main rubber elastic body 16. Yes. The first mounting bracket 12 is attached to the power unit of the automobile, and the second mounting bracket 14 is attached to the vehicle body, so that the power unit is connected to the vehicle body in a vibration-proof manner.

  In FIG. 1, the state of the vehicle engine mount 10 alone before being mounted on the vehicle is shown, but in the mounted state on the vehicle, the shared support load of the power unit is in the mount axis direction (in FIG. 1), the first mounting bracket 12 and the second mounting bracket 14 are displaced toward each other in the mount axis direction, and the main rubber elastic body 16 is elastically deformed. Further, under such a mounted state, main vibrations to be vibration-proofed are input in the direction of the mount axis. In the following description, unless otherwise specified, the vertical direction refers to the vertical direction in FIG.

  More specifically, the first mounting bracket 12 has a substantially circular block shape, and mounting bolts 18 project upward. The first mounting bracket 12 can be attached to the power unit by fastening the attachment bolt 18 to the power unit side.

  On the other hand, the second mounting member 14 has a large-diameter, generally cylindrical shape, and is attached to the vehicle body via a bracket member (not shown). The first mounting bracket 12 is spaced apart from the opening on the upper side of the second mounting bracket 14, and the main rubber elastic body 16 is disposed between the opposing surfaces of the first mounting bracket 12 and the second mounting bracket 14. It is arranged.

  The main rubber elastic body 16 has a substantially truncated cone shape, and the outer peripheral surface of the first mounting member 12 is fixed to the end surface on the small diameter side, and the second outer peripheral surface on the large diameter side end portion. The inner peripheral surface of the mounting bracket 14 is fixed. Thereby, the first mounting bracket 12 and the second mounting bracket 14 are elastically connected via the main rubber elastic body 16, and the upper opening of the second mounting metal 14 is the main rubber elastic body 16. It is closed fluid tightly. Further, an inverted bowl-shaped large-diameter recess 20 is formed on the large-diameter side end face of the main rubber elastic body 16 so as to open toward the inside of the second mounting bracket 14, and the second mounting bracket A thin seal rubber layer 22 is formed on the inner peripheral surface of 14. In addition, a diaphragm 24 as a flexible film is disposed at the lower end of the second mounting bracket 14.

  The diaphragm 24 is formed of a thin rubber film that has a substantially circular shape and is easily deformable as a whole, and a large-diameter ring-shaped fixing fitting 26 is fixed to an outer peripheral edge portion. The fixing bracket 26 is inserted into the lower end portion of the second mounting bracket 14, and the second mounting bracket 14 is subjected to diameter reduction processing such as an eight-way drawing, whereby the fixing bracket 26 is interposed via the seal rubber layer 22. The second mounting bracket 14 is fixed in close contact. Thus, the diaphragm 24 is fixed to the second mounting bracket 14, and the lower opening of the second mounting bracket 14 is fluid-tightly closed by the diaphragm 24.

  Further, a partition wall member 28 is disposed between the axially opposing surfaces of the main rubber elastic body 16 and the diaphragm 24 inside the second mounting bracket 14. As shown in FIG. 2, the partition member 28 has a substantially circular block shape as a whole, and is relatively made of a metal material such as an aluminum alloy or a synthetic resin material such as polypropylene (PP). It is formed using a material having high rigidity. The partition member 28 includes a partition metal member 30 as a partition member and a cover metal member 32 as a pressure receiving chamber side cover member.

  As shown in FIGS. 3 and 4, the partition fitting 30 has a substantially disk shape, and a circular accommodation recess 34 that opens upward is formed in the central portion in the radial direction. A central protrusion 36 that rises from the bottom wall portion projects from the radial central portion of the receiving recess 34, and an outer peripheral protrusion that protrudes radially inward from the peripheral wall portion of the receiving recess 34. A plurality of 38 are provided at equal intervals in the circumferential direction. Locking projections 40 project from the upper end surfaces of the central projection 36 and the outer circumferential projections 38. Further, a plurality of substantially fan-shaped communication ports 42 are provided in the housing recess 34 at the center side of the bottom wall portion around the center protrusion 36 so as to be spaced apart in the circumferential direction. In addition, a lower peripheral groove 44 that is open to the upper end surface and the outer peripheral surface and continuously extends in the circumferential direction with a predetermined length (a little less than a half circumference in the present embodiment) is formed in the outer peripheral portion of the partition member 30. At the same time, an opening 46 is formed on one end side in the circumferential direction of the lower circumferential groove 44 and opens on the lower end surface of the partition member 30.

  On the other hand, the cover metal fitting 32 has a shallow, substantially bottomed cylindrical shape. An upper circumferential groove 48 is formed in the cylindrical portion of the cover metal fitting 32 so as to open to the outer peripheral surface and continuously extend in the circumferential direction with a predetermined length (in this embodiment, slightly less than one round). An opening 50 that opens to the inner wall surface is formed on one end side in the circumferential direction of 48, and a connection window 52 is formed on the other end side in the circumferential direction of the upper circumferential groove 48, so Open to the end face. In addition, a plurality of through holes 54 are provided in the center side of the bottom wall portion of the cover metal member 32 so as to be spaced apart in the circumferential direction, and the outer circumferential side of the bottom wall portion is formed in a longitudinal shape in the circumferential direction. A plurality of extending communication holes 56 are provided to be spaced apart in the circumferential direction. Further, a plurality of locking holes 58 are provided at positions different from the communication hole 56 on the radial center portion of the bottom wall portion of the cover fitting 32 and the outer peripheral side of the bottom wall portion.

  The cover metal fitting 32 is superimposed on the partition metal fitting 30 from above, and the locking projections 40 of the partition metal fitting 30 are inserted into the locking holes 58 of the cover metal fitting 32 and locked. Thus, the partition member 30 and the cover member 32 are fixed to each other while being aligned in the circumferential direction, so that the partition wall member 28 is configured. Further, the opening of the accommodation recess 34 of the partition metal 30 is covered with a cover metal 32. Further, the upper opening of the lower circumferential groove 44 of the partition fitting 30 is covered with the cover fitting 32, and the other circumferential ends of the lower circumferential groove 44 and the upper circumferential groove 48 of the cover fitting 32 are mutually connected. They are aligned and connected through the connection window 52. As a result, the upper peripheral groove 48 and the lower peripheral groove 44 are connected in series to form a peripheral groove that spirally extends the outer peripheral portion of the partition wall member 28 with a predetermined length.

  Prior to the assembly of the diaphragm 24 to the second mounting bracket 14, the partition wall member 28 is inserted into the second mounting bracket 14, and the second mounting bracket 14 is subjected to diameter reduction processing such as an eight-way stop. As a result, the partition member 28 is fixed in close contact with the second mounting member 14 via the seal rubber layer 22. Thereby, the space between the axially opposed surfaces of the main rubber elastic body 16 and the diaphragm 24 inside the second mounting bracket 14 is fluid-divided by the partition wall member 28.

  On one side (the upper side in FIG. 1) sandwiching the partition wall member 28, a pressure receiving chamber 60 is formed in which a part of the wall portion is composed of the main rubber elastic body 16 and pressure fluctuation is caused by vibration input. In addition, on the other side (lower side in FIG. 1) sandwiching the partition wall member 28, there is formed an equilibrium chamber 62 in which a part of the wall portion is constituted by the diaphragm 24 and volume change is easily allowed. ing. In the pressure receiving chamber 60 and the equilibrium chamber 62, for example, an incompressible fluid made of a low-viscosity fluid having a viscosity of 0.1 Pa · s or less such as water, alkylene glycol, or polyalkylene glycol is sealed.

  In addition, the upper and lower peripheral grooves 44 and 48 of the partition wall member 28 are fluid-tightly closed by the second mounting bracket 14 via the seal rubber layer 22, so that the outer peripheral portion of the partition wall member 28 is spirally predetermined. The orifice passage 64 is formed extending in the length (in the present embodiment, slightly less than one turn to slightly less than one turn). One end of the orifice passage 64 is connected to the pressure receiving chamber 60 through the opening 50 of the cover fitting 32, and the other end of the orifice passage 64 is connected to the equilibrium chamber 62 through the opening 46 of the partition fitting 30. Has been. As a result, the pressure receiving chamber 60 and the equilibrium chamber 62 are communicated with each other through the orifice passage 64, and a fluid flow occurs through the orifice passage 64 according to the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 due to vibration input. An anti-vibration effect based on a fluid action such as a resonance action of the fluid is exhibited. Note that the resonance frequency of the fluid flowing through the orifice passage 64 is set based on the passage cross section, the passage length, and the like. In this embodiment, the resonance frequency is in a low frequency range of about 10 Hz corresponding to, for example, an engine shake of an automobile. Is set.

  In addition, an annular housing recess 34 covered with the cover metal 32 in the partition metal 30 communicates with the pressure receiving chamber 60 through the through hole 54 and the communication hole 56 of the cover metal 32, and the communication port of the partition metal 30. 42 is in communication with the equilibration chamber 62. Here, prior to the assembly of the partition fitting 30 and the cover fitting 32, the accommodation recess 34 is closed so as to overlap the bottom wall portion from the upper opening of the accommodation recess 34 on the pressure receiving chamber 60 side. An elastic rubber plate 66 is provided as a rubber elastic plate.

  As shown in FIGS. 5 and 6, the elastic rubber plate 66 has a substantially circular flat plate shape as a whole and is formed using a rubber elastic material. A central mounting portion 68 having a substantially cylindrical shape is formed at the central portion in the radial direction of the elastic rubber plate 66. The central protrusion 36 of the partition metal fitting 30 is inserted into the inner hole 70 of the central mounting portion 68, and the lower end surface of the central mounting portion 68 is radially inward of each communication port 42 in the bottom wall portion of the housing recess 34. The upper end surface of the central mounting portion 68 is overlapped with the lower end surface radially inward of each through hole 54 in the bottom wall portion of the cover fitting 32.

  Further, three spoke-shaped holding portions 72, 72, 72 extending radially from the central mounting portion 68 toward the outer peripheral portion of the elastic rubber plate 66 are formed at equal intervals in the circumferential direction, and each spoke-shaped holding portion 72 is The bottom wall portion between each pair of communication ports 42, 42 adjacent in the circumferential direction of the housing recess 34, and the bottom between the plurality of through holes 54 of the cover metal fitting 32 positioned to face the bottom wall portion in the axial direction. It is arranged between the walls.

  Further, on the outer peripheral side of the lower end surface of the elastic rubber plate 66, an annular seal lip 78 is provided so as to be superimposed on the radially outer portion of each communication port 42 in the bottom wall portion of the housing recess 34. Yes. In short, the elastic rubber plate 66 is overlapped so as to cover the plurality of communication ports 42 of the partition member 30, and the outer peripheral edge portion of the elastic rubber plate 66 is more radial than the outer peripheral edge portion of each communication port 42. Located outside. In particular, in the present embodiment, the outer peripheral edge of the elastic rubber plate 66 is positioned radially outward from the through holes 54 of the cover metal member 32 and positioned radially inward from the communication holes 56. ing. Thereby, each communicating hole 56 is provided in the position which remove | deviated the site | part opposite to the axial direction with respect to the outer periphery part of the elastic rubber board 66. As shown in FIG.

  Furthermore, three arc-shaped contact holding portions 74 are formed at equal intervals in the circumferential direction on the outer peripheral edge portion of the elastic rubber plate 66, and in particular, the circumferential central portion of each contact holding portion 74 is formed. Further, it is in contact with the tip portion of each spoke-like holding portion 72 that extends radially outward from the central mounting portion 68.

  In the elastic rubber plate 66 of the present embodiment, the thicknesses of the central attachment portion 68, the spoke-like holding portion 72, and the contact holding portion 74 are substantially the same as each other, and the bottom wall portion of the cover metal fitting 32 is It is made larger than the dimension between the axially facing surfaces of the bottom wall portion of the housing recess 34 of the partition fitting 30 (the axial separation distance between both bottom wall portions). Thereby, the central mounting portion 68, the spoke-shaped holding portion 72, and the contact holding portion 74 are compressed and deformed between the axial directions of both bottom wall portions of the partition metal fitting 30 and the cover metal fitting 32 in the housing recess 34, and The compressive deformation state is held by the fixing force of the partition fitting 30 and the cover fitting 32, and the central mounting portion 68, the spoke-like holding portion 72, and the contact holding portion 74 are held by the partition wall member 28 with pressure. Further, the central mounting portion 68 is elastically fitted and fixed to the central protrusion 36 of the partition metal 30. Further, the outer peripheral surface of the central portion in the circumferential direction of each abutment holding portion 74 is in pressure contact with the inner peripheral surface of each outer peripheral projection 38 of the partition metal fitting 30 in the radial direction. As a result, the elastic rubber plate 66 is held in a state where the elastic rubber plate 66 is overlaid on the partition metal fitting 30.

  On the other hand, in the elastic rubber plate 66, each region having a substantially fan shape surrounded by the central attachment portion 68 and each pair of spoke-like holding portions 72, 72 and each pair of contact holding portions 74, 74 adjacent in the circumferential direction. Is made sufficiently smaller than the dimension between the axially opposed surfaces of the bottom wall portion of the cover fitting 32 and the bottom wall portion of the housing recess 34 of the partition fitting 30. Three substantially fan-shaped regions are provided at equal intervals in the circumferential direction of the elastic rubber plate 66, and each region covers the entirety of each communication port 42 in a shape larger than each communication port 42, Each communication port 42 is aligned in the circumferential direction. Further, such a region is disposed to face the cover metal member 32 with a predetermined distance in the overlapping direction of the elastic rubber plate 66 and the partition metal member 30. The pressure in the pressure receiving chamber 60 is applied to one surface of each region through the through hole 54 and the communication hole 56 of the cover metal 32, and the communication port 42 of the partition member 30 is applied to the other surface of each region. The pressure of the equilibrium chamber 62 is exerted through. In short, an elastic valve portion serving as an elastic deformation region capable of allowing elastic deformation of the elastic rubber plate 66 in accordance with a pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 in a state where the elastic rubber plate 66 is superimposed on the partition member 30. 76 is constituted by such a substantially fan-shaped region.

  In particular, in the present embodiment, the outer peripheral edge of the elastic valve portion 76 is positioned radially outward from the outer peripheral edge of the communication port 42 and is radially inward from the outer peripheral edge of the contact holding portion 74. Is located. Further, the circumferential central portion of the outer peripheral edge portion of each elastic valve portion 76 between each pair of contact holding portions 74, 74 adjacent in the circumferential direction of the elastic rubber plate 66 is the outer peripheral edge portion of each communication port 42. It is aligned with the circumferential central portion in the circumferential direction.

  Further, as shown in FIG. 7, a notch shape extending in the radial direction is formed on the circumferential end portion side of each contact holding portion 74 on both sides in the circumferential direction across the outer peripheral edge portion of the elastic valve portion 76. A step portion 82 as an opposing contact protrusion is formed integrally with the elastic valve portion 76 and the contact holding portion 74 via the groove portion 80. The thickness dimension (height dimension) of the stepped portion 82 is made larger than the thickness dimension of the elastic valve portion 76 and made smaller than the thickness dimension of the contact holding portion 74. Then, the stepped portion 82 is spaced apart from the cover fitting 32 while the elastic rubber plate 66 is superimposed on the partition fitting 30. A portion of the outer peripheral edge of the elastic rubber plate 66 from the stepped portion 82 to the central portion in the circumferential direction of the abutment holding portion 74 has a radially outer portion than the respective communication ports 42 of the partition member 30 as an edge of the communication port 42. It extends along.

  As is clear from the above description, the central mounting portion 68, the spoke-like holding portion 72, and the contact holding portion 74 of the present embodiment are larger in thickness than the elastic valve portion 76 of the elastic rubber plate 66. In addition, the thick rubber portion is configured to be sandwiched and held between the cover metal fitting 32 and the partition metal fitting 30, and the rigidity of the thick rubber portion is sufficiently larger than the rigidity of the elastic valve portion 76. Has been. Moreover, the cover metal fitting 32 of this embodiment functions as a press holding member that presses the thick rubber portion against the partition metal fitting 30. In particular, in the present embodiment, the peripheral edge portion of the elastic valve portion 76 excluding the outer peripheral edge portion is constrained by the central attachment portion 68, the spoke-like holding portion 72, the contact holding portion 74, and the step portion 82, while the elastic valve portion 76. Since the step portions 82 located on both sides in the circumferential direction of the outer peripheral edge of the elastic valve portion are separated from the cover metal fitting 32, the spring characteristics of the central portion and the outer peripheral edge of the elastic valve portion 76 can It is made softer than the spring characteristics on the inner and circumferential sides.

  In the engine mount 10 for an automobile having such a structure, when a low-frequency large-amplitude vibration corresponding to an engine shake is input during driving of the automobile, a pressure difference is generated between the pressure receiving chamber 60 and the equilibrium chamber 62. The fluid flow through the orifice passage 64 is caused between the two chambers 60 and 62.

  Here, when the vibration corresponding to the engine shake is, for example, ± 1 to 2 mm, the step portion 82 of the elastic rubber plate 66 is prevented from being greatly deformed and displaced so as to contact the cover metal fitting 32. The elastic rubber plate 66 is overlaid on the partition fitting 30 so that the communication ports 42 of the partition fitting 30 are kept fluid-tightly closed by the elastic valve portions 76. In particular, at the time of such vibration input, the outer peripheral edge of the elastic valve portion 76 is separated from the partition metal fitting 30, as indicated by the two-dot chain line in FIG. Even in the case where the communication port 42 may open, the step portion 82 having a thickness dimension larger than that of the elastic valve portion 76, the thickness dimension larger than the step portion 82, and the partition member On the basis of the hard spring characteristic of the contact holding part 74 or the like constrained by 28, the stepped part 82 becomes the cover fitting 32 by increasing the deformation to a region where the spring characteristic of the elastic valve part 76 becomes nonlinearly steeply hard. The deformation in which the outer peripheral edge of the elastic valve portion 76 is greatly separated from the partition metal 30 is suppressed so as to come into contact with. As a result, the pressure fluctuation in the pressure receiving chamber 60 is prevented from being unnecessarily escaped and absorbed through the communication port 42, and the flow amount of the fluid flowing through the orifice passage 64 is sufficiently secured. Therefore, a stable anti-vibration effect (high damping effect) can be obtained.

  On the other hand, when high-frequency small-amplitude vibration having an amplitude corresponding to traveling noise or the like is about ± 0.05 to 0.1 mm, for example, the orifice passage 64 is substantially caused by the antiresonant action of the fluid flowing through the orifice passage 64. The pressure receiving chamber 60 of the elastic valve portion 76 is slightly deformed as shown by a two-dot chain line in FIG. 7 based on the relatively soft spring characteristics of the central portion and the outer peripheral edge portion of the elastic valve portion 76. Due to the hydraulic pressure absorbing action, the intended vibration isolation effect (low dynamic spring effect) can be stably obtained.

  Further, when an excessive or shocking vibration load having an amplitude of, for example, ± 2 mm or more is input, such as when the automobile gets over a step or travels on a road surface with large unevenness, the pressure in the pressure receiving chamber 60 is greatly reduced. There is a case. Therefore, in this embodiment, as shown in FIG. 8, the stepped portion 82 of the elastic rubber plate 66 is separated from the partition fitting 30 and contacts the cover fitting 32 when the pressure receiving chamber 60 is in a reduced pressure state. A large pressure is exerted on the elastic valve portion 76 to the extent that it comes into contact. That is, when the above excessive shock vibration load is input, in addition to the soft spring characteristic area of the elastic valve part 76 at the center part or the outer peripheral edge part, the periphery of the outer peripheral edge part of the communication port 42 in which the step part 82 is arranged. Since the deformation amount that spreads to both sides in the direction and the elastic valve portion 76 is separated from the partition metal fitting 30 is ensured, the opening amount of the communication port 42 can be increased as a whole. Therefore, the pressure receiving chamber 60 and the equilibrium chamber 62 are short-circuited quickly and reliably, and the generation of cavitation bubbles is suppressed based on the elimination of the overnegative pressure state of the pressure receiving chamber 60. As a result, the water accompanying the collapse of the bubbles is reduced. The effect of suppressing shocking abnormal noise and vibration caused by the impact pressure can be effectively exhibited.

  In particular, in the present embodiment, non-linearization means for making the elastic characteristics non-linearly harder as the elastic deformation of the elastic valve section 76 is increased by making the elastic characteristics in the elastic valve section 76 of the elastic rubber plate 66 non-linear. ) A thick rubber portion comprising a central mounting portion 68, a spoke-like holding portion 72, and a contact holding portion 74 provided around the elastic valve portion 76 is held between the cover metal fitting 32 and the partition metal fitting 30 by pressure. (B) The thickness dimension of the elastic valve portion 76 is changed so as to gradually decrease from both sides in the circumferential direction toward the central portion using the spoke-like holding portion 72 and the stepped portion 82. (C) When the elastic valve portion 76 is elastically deformed so as to be largely separated from the partition fitting 30, the step portion 82 abuts on the cover fitting 32. That is, since the non-linearization means is configured by using the shape and assembly structure of the existing cover metal fitting 32 and the partition metal fitting 30, it uses an elastic rubber plate 66 made of a rubber material. Simplification of the structure and reduction of manufacturing costs can be advantageously achieved.

  Several automotive engine mounts having different forms from the automotive engine mount 10 of the first embodiment will be described below with respect to the fluid-filled vibration isolator of the present invention. About the member and site | part made into the substantially same structure, those detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  That is, FIGS. 9 and 10 show an elastic rubber plate 84 employed in an automobile engine mount as a second embodiment of the present invention. A pair of contact protrusions 86 as opposed contact protrusions are formed. The contact protrusions 86, 86 are integrally formed with the elastic valve portion 76, project upward, are spaced apart from each other in the circumferential direction, and each circumferential end of the contact holding portion 74. It is spaced apart from the part in the circumferential direction. Further, the height dimension of the abutting protrusion 86 is made smaller than the height dimension of the abutting holding portion 74, and the elastic rubber plate 84 is disposed away from the cover metal fitting 32 while being superposed on the partition metal fitting 30. ing. Further, the tip portion of the contact protrusion 86 has a substantially hemispherical shape.

  By employing the elastic rubber plate 84 having such a contact protrusion 86, the spring rigidity can be reduced as compared with the case where the opposing contact protrusion is integrally formed with the contact holding portion 74. The spring of the elastic valve portion 76 can be further reduced. In addition to the fact that a plurality of portions that abut against the cover metal fitting 32 at the outer peripheral edge of the elastic rubber plate 84 are provided apart from each other in the circumferential direction, the impact area is reduced by reducing the contact area. The loud hitting sound associated with the hit can be effectively reduced.

  Note that the shape, size, structure, number, arrangement, and the like of the contact protrusion 86 are not limited. For example, the automobile engine as the third embodiment of the present invention shown in FIGS. As in the case of the elastic rubber plate 88 employed in the mount, one contact protrusion 86 may be provided at the center in the circumferential direction of the outer peripheral edge of each elastic valve portion 76.

  Further, in the circumferential end portion of the contact holding portion 74, for example, in FIG. 13 and FIG. 14 without forming a stepped portion 82 as an opposite contact protrusion having a height dimension different from that of the contact holding portion 74, for example. An elastic rubber plate 90 employed in an automobile engine mount as a fourth embodiment of the present invention as shown may be used. That is, the recess 92 is formed in the cover metal 32 disposed opposite to both sides in the circumferential direction of the contact holding portion 74 in the mount axis direction, which is the overlapping direction of the elastic rubber plate 90 and the partition metal 30, thereby holding the contact. Both side portions of the portion 74 in the circumferential direction are opposed to the cover metal fitting 32 with a predetermined distance. The opposing abutment protrusion 94 is constituted by circumferentially opposite side portions having the same height as the circumferentially central portion of the abutment holding portion 74.

  Further, as shown in FIGS. 15 and 16, an elastic rubber plate 96 employed in an automobile engine mount as the fifth embodiment of the present invention may be used. That is, the stepped portions 98 as opposed contact protrusions integrally formed on both sides in the circumferential direction of the contact holding portion 74 are gradually increased in height toward the outer side in the circumferential direction separated from the contact holding portion 74. It is made smaller. Thereby, the thickness dimension of the elastic valve part 76 is gradually changed from the both sides in the circumferential direction toward the center.

  Further, in the first to fifth embodiments, the shape and structure of the cover fitting that is arranged so as to partially vary the thickness dimension of the elastic rubber plate or to cover the elastic rubber plate from the pressure receiving chamber side. However, the non-linearization means is configured, but for example, a configuration such as an automobile engine mount as the sixth embodiment of the present invention using an elastic rubber plate 100 as shown in FIGS. It can be adopted. That is, the elastic rubber plate 100 is configured by fixing the reinforcing metal fitting 104 as a reinforcing member harder than the rubber plate 102 in an embedded state to the flat rubber plate 102 having a substantially constant thickness dimension. Yes. The non-linearization means is configured by utilizing the difference in rigidity between the portion where the reinforcing metal fitting 104 is disposed and the portion where the reinforcing metal fitting 104 is not disposed.

  Specifically, a small-diameter boss-like portion 106 formed in the central portion of the reinforcing metal fitting 104 is disposed in the central portion of the rubber plate 102 and extends from the boss-like portion 106 radially toward the outer peripheral side. 108 is disposed, and a divided rim-shaped portion 110 that extends in an arc shape in the circumferential direction from the tip portion of the spoke-shaped portion 108 is disposed along the outer peripheral edge portion of the rubber plate 102. Thereby, the elastic valve part 76 is comprised by the substantially fan-shaped part in which the reinforcement metal fitting 104 is not arrange | positioned in the rubber plate 102. FIG. Further, the abutment holding portion is constituted by the divided rim-like portion 110 of the reinforcing metal fitting 104. Furthermore, the notch-shaped part 112 is formed in the outer peripheral edge part of the circumferential direction center part of the division | segmentation rim-shaped part 110, and the spring characteristic of a contact holding | maintenance part can be adjusted. Furthermore, a strip portion 114 as an extension holding portion is integrally formed so as to extend in the circumferential direction from the circumferential end portion of the divided rim-shaped portion 110 toward the elastic valve portion 76, and the strip portion 114. Is made smaller than the split rim-shaped portion 110, and the rigidity is low, and the elastic characteristics on both sides in the circumferential direction of the elastic valve portion 76 are centered in the circumferential direction due to the low-rigidity portion of the reinforcing metal fitting 104 composed of the strip 114. By making it harder than the portion, the non-linearization means is constituted.

  Although several embodiments of the present invention have been described above, the present invention is not limited to specific descriptions by these embodiments, and various changes and modifications based on the knowledge of those skilled in the art. Needless to say, any of these embodiments is included in the scope of the present invention without departing from the spirit of the present invention. .

  For example, in the above-described embodiment, the portion having higher rigidity than the elastic valve portion 76 of the elastic rubber plate is configured by the thick rubber portion or the portion in which the reinforcing metal fitting is embedded in the rubber plate. By providing protrusions that make partial contact or restrain deformation to a rubber plate with a constant thickness dimension on the partition fitting or cover fitting, a high-rigidity portion can be formed by the portion where the protrusion hits the rubber plate, Alternatively, the high-rigidity portion can be configured by a single-layer structure of a rigid member such as a metal fitting or a synthetic resin.

  In addition, the central mounting part, spoke-like holding part, contact holding part, etc. of the elastic rubber plate need to be held between the cover metal fitting and the partition metal fitting with the elastic rubber plate superimposed on the metal fitting. For example, the center mounting portion, the spoke-shaped holding portion, and the abutting holding portion may be simply brought into contact with the cover fitting, or may be arranged to face each other with a predetermined distance from the cover fitting.

  In the embodiment, the central portion (central mounting portion 68) of the elastic rubber plate 66 is elastically fitted to the central protrusion 36 of the partition member 30, and the central portion and the outer peripheral portion of the elastic rubber plate 66 are The elastic rubber plate 66 is fixed to the partition member 28 by being clamped and held by the partition member 28. For example, the elastic rubber plate is screwed or bolted to at least one of the cover fitting and the partition fitting in the partition member. It is also possible to fix with, for example.

  In the automobile engine mount 10 of the above-described embodiment, the structure in which the single orifice passage 64 is provided is employed, but a plurality of orifice passages may be employed.

  In addition, in the above-described embodiment, specific examples of the present invention applied to an engine mount for automobiles have been described. However, the present invention is not limited to automobile bodies, differential mounts, suspension member mounts, suspension bushes, etc. Any of the above can be applied to the fluid-filled vibration isolator for isolating the various vibrators.

It is a longitudinal cross-sectional view which shows the engine mount for motor vehicles as 1st embodiment of this invention, Comprising: The figure corresponding to the II cross section of FIG. The top view which shows the state which assembled | attached the elastic rubber board to the partition member which comprises a part of engine mount for motor vehicles of FIG. The top view which shows the state which assembled | attached the elastic rubber board to the partition metal fitting which comprises a part of partition member of FIG. The bottom view of the partition metal fitting of FIG. The top view of the elastic rubber board of FIG. VI-VI sectional drawing of FIG. The enlarged view of the VII-VII cross section of FIG. The longitudinal cross-sectional view which expands and shows the principal part of the engine mount for motor vehicles of FIG. 1, and shows one operation state different from FIG. The top view of the elastic rubber board employ | adopted as the engine mount for motor vehicles as 2nd embodiment of this invention. XX sectional drawing of FIG. The top view of the elastic rubber board employ | adopted as the engine mount for motor vehicles as 3rd embodiment of this invention. XII-XII sectional drawing of FIG. The top view of the elastic rubber board employ | adopted as the engine mount for motor vehicles as 4th embodiment of this invention. FIG. 14 is a longitudinal sectional view showing, in an enlarged manner, one operation state of a main part in the automobile engine mount of FIG. 13, corresponding to FIG. 7. The top view of the elastic rubber board employ | adopted as the engine mount for motor vehicles as 5th embodiment of this invention. FIG. 16 is a longitudinal sectional view showing, in an enlarged manner, an operation state of a main part in the automobile engine mount of FIG. 15, corresponding to FIG. 7. The top view of the elastic rubber board employ | adopted as the engine mount for motor vehicles as the 6th embodiment of this invention. XVIII-XVIII sectional drawing of FIG.

Explanation of symbols

10: Automotive engine mount, 12: First mounting bracket, 14: Second mounting bracket, 16: Rubber elastic body, 24: Diaphragm, 30: Partition bracket, 42: Communication port, 60: Pressure receiving chamber, 62 : Equilibrium chamber, 64: Orifice passage, 66: Elastic rubber plate, 74: Contact holding part, 76: Elastic valve part

Claims (7)

The first mounting member and the second mounting member are connected by a main rubber elastic body, and a pressure receiving chamber in which a part of the wall portion is configured by the main rubber elastic body and a part of the wall portion is a flexible film. In a fluid-filled vibration isolator having a configured equilibrium chamber, in which an incompressible fluid is enclosed in the pressure receiving chamber and the equilibrium chamber, and an orifice passage is provided to communicate the pressure receiving chamber and the equilibrium chamber with each other. ,
To form a communication opening for communicating the equilibrium chamber with pressure receiving chamber against the partition member for partitioning said equilibrium chamber and said pressure-receiving chamber, are superimposed from the receiving chamber side closes the continuous opening against continuous opening In addition, a closed rubber elastic plate that is opened based on elastic deformation is disposed so that the pressure of the pressure receiving chamber is exerted on one surface of the closed rubber elastic plate, and the pressure of the equilibrium chamber is applied to the other surface through the communication port. In the circumferential direction of the closed rubber elastic plate, a plurality of contact holding portions that are always held in an overlapping state with respect to the partition member are provided on the circumference at the outer peripheral edge of the closed rubber elastic plate. It is elastically deformed based on the pressure difference between the pressure receiving chamber and the equilibrium chamber between the adjacent contact holding portions adjacent to each other and is separated from the partition member to open the communication port, and the through the communication port. Pressure chamber and the chamber Forming an elastic deformation region to allow fluid flow between the衡室, further elasticity in the elastic deformation region elastic properties of the elastic deformation region provided on the outer peripheral edge portion of the closure rubber elastic plate as a non-linear A fluid-filled vibration isolator provided with non-linear means for making the elastic characteristics harder in a non-linear manner as the amount of deformation increases.   A central mounting portion is integrally formed at the central portion of the closing rubber elastic plate, and this central mounting portion is fixedly attached to the partition member, while radially extending from the central mounting portion toward the outer peripheral side. The fluid-filled type vibration damping device according to claim 1, wherein a spoke-like holding portion is provided to extend in a circumferential direction from a tip portion of the spoke-like holding portion. apparatus.   The abutment holding portion is constituted by a thick rubber portion, and a pressure holding member is provided on the opposite side of the partition member across the thick rubber portion, and the thick rubber portion is the pressure holding member. The elastic deformation region located between the thick rubber portions is made thinner than the thick rubber portion. And the thickness of the elastic deformation region is changed so as to gradually or gradually decrease from the thick rubber portion on both sides in the circumferential direction toward the central portion in the circumferential direction, thereby configuring the non-linearization means The fluid-filled vibration isolator according to claim 1 or 2.   A reinforcing member that is harder than the rubber elastic body is fixed to the outer peripheral edge portion of the closing rubber elastic plate so that the contact holding portion is configured by the reinforcing member, and is positioned between the contact holding portions in the circumferential direction. The elastic deformation region is formed so that the reinforcing member is not fixed and can be easily deformed. On the other hand, the reinforcing member extends from the corresponding contact holding portion toward the elastic deformation region in the circumferential direction, The non-linearization means is constituted by the extension holding portion having elastic properties on both sides in the circumferential direction of the elastic deformation region that are harder than the central portion in the circumferential direction by the extension holding portion. The fluid-filled vibration isolator according to any one of claims 1 to 3.   A pressure receiving chamber side cover member that covers the elastic deformation region of the closing rubber elastic plate at a distance from the pressure receiving chamber side is provided, and one surface is provided on the opposing surface of the elastic deformation region and the pressure receiving chamber side cover member. An opposing abutting protrusion that protrudes toward the other end and faces the other end with a predetermined distance from the other, and the elastic deformation region is elastically deformed and separated from the partition member. The fluid-filled vibration isolator according to any one of claims 1 to 4, wherein the non-linearization means is configured by an opposing abutting protrusion abutting against the other.   A pressure receiving chamber side cover member that covers the blocking rubber elastic plate at a distance from the pressure receiving chamber side is provided, and the pressure receiving chamber side cover member includes the pressure receiving chamber side cover member and the closing rubber elastic plate. The communication hole which connects an internal area | region between this to the said pressure receiving chamber is provided in the position which remove | deviated the opposition site | part with respect to the said elastic deformation area | region in this obstruction | occlusion rubber elastic board. Fluid-filled vibration isolator.   The orifice passage is formed so as to extend in the circumferential direction of the outer peripheral portion of the partition member while the closing rubber elastic plate is disposed so as to overlap the central portion of the partition member. The fluid-filled vibration isolator according to claim 6.

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