JP2006234111A - Fluid sealing type vibration isolator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid sealing type vibration isolator having an improved structure which can more effectively fulfill both of a vibration isolation effect obtained by a first orifice passage tuned to a low frequency band and a vibration isolation effect obtained by a second orifice passage tuned to a frequency band higher than the frequency band of the first orifice passage. <P>SOLUTION: An intermediate chamber 82 is formed and noncompressible fluid is sealed therein. A movable member 80 is located between the intermediate chamber 82 and a pressure receiving chamber 50 and allowed to displace or deform by a predetermined amount so as to limitedly transmit pressure variation between the pressure receiving chamber 50 and the intermediate chamber 82. The second orifice passage 94 is formed to communicate the intermediate chamber 82 to an equilibrium chamber 52. The second orifice passage 94 is tuned to the frequency band higher than the first orifice passage 86 and a plurality of portions of the second orifice passage 94 are opened to the intermediate chamber 82. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vibration isolator used as, for example, an automobile engine mount or a body mount, and more particularly to a fluid-filled type in which a vibration-proof effect is obtained by utilizing the flow action of an incompressible fluid sealed inside. The present invention relates to a vibration isolator.

  2. Description of the Related Art Conventionally, a fluid-filled vibration isolator is known as a type of anti-vibration coupling body and anti-vibration support body mounted between members constituting a vibration transmission system. This vibration isolator generally connects a first mounting member and a second mounting member to each other with a main rubber elastic body, and includes a pressure receiving chamber and a wall section in which a part of the wall portion is configured with the main rubber elastic body. Equilibrium chambers partially made of flexible membranes were provided, incompressible fluid was sealed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber were connected to each other through an orifice passage. It is structured. Then, at the time of vibration input between the first mounting member and the second mounting member, the resonance of the fluid that is caused to flow through the orifice passage based on the relative pressure fluctuation caused between the pressure receiving chamber and the equilibrium chamber. The vibration-proofing effect based on the flow action (orifice effect) such as action can be exhibited.

  By the way, the vibration-proofing effect based on the orifice effect can only be effectively exhibited in a specific frequency range that has been tuned in advance. Decrease in vibration performance becomes a problem. Therefore, the first orifice passage tuned in the low frequency range and the second orifice passage tuned in the higher frequency range are provided, and the resonance action of the fluid against vibrations in two different frequency ranges, respectively. It is conceivable that the anti-vibration effect based on the above will be exhibited.

  However, the second orifice passage tuned to the high frequency region has a smaller flow resistance than the first orifice passage. Therefore, in order to ensure the fluid flow amount through the first orifice passage when the vibration is input in the low frequency range, it is necessary to limit the flow amount of the fluid that flows through the second orifice passage.

  Therefore, for example, as described in Japanese Patent Application Laid-Open No. 2000-310272 (Patent Document 1), a predetermined amount of displacement or deformation is allowed in the opening on the pressure receiving chamber side or the equilibrium chamber side of the second orifice passage. There has been proposed a structure in which a movable member is disposed. In such an anti-vibration device, the amount of fluid flow through the second orifice passage is limited when a large amplitude vibration in the low frequency range is input, and the amount of fluid flow through the first orifice passage is ensured. Anti-vibration effect is exhibited in the low frequency range. In addition, when a vibration having a small amplitude is input in a frequency range higher than the tuning frequency of the first orifice passage, the fluid flow through the second orifice passage is caused by the displacement or deformation of the movable member. Anti-vibration effect is obtained.

  In order to effectively secure the amount of fluid flow through the second orifice passage based on such displacement or deformation of the movable member and effectively obtain the vibration isolation effect by the second orifice passage, the movable member It is desirable to secure a sufficient effective area on the pressure receiving chamber side and the equilibrium chamber side. As one of the measures, for example, as shown in Japanese Patent Application Laid-Open No. 2003-74617 (Patent Document 2), a part of the wall portion is composed of a movable member between the movable member and the second orifice passage. It is conceivable to secure a large effective area of the movable member by forming the intermediate chamber.

  However, as a result of studies by the present inventors, it is clear that even when such an intermediate chamber is formed, the vibration isolation effect by the second orifice passage may not be improved as much as expected. In this respect, there was still room for improvement.

JP 2000-310272 A JP 2003-74617 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is the first orifice passage tuned to the low frequency range and the tuning to the higher frequency range. It is an object of the present invention to provide a fluid-filled vibration isolator having an improved structure, in which any of the vibration-proofing effects of the second orifice passage formed can be more effectively exhibited.

  In order to solve the above-mentioned problems, the present inventor conducted a number of experiments and studies on a conventional fluid-filled vibration isolator, and as a result, discovered one interesting fact. That is the fact that by providing the opening of the second orifice passage at a specific position in the intermediate chamber, the displacement or deformation of the movable member is unstable.

  In analyzing this fact, the present inventor has focused on the fact that the fluid flow in the vicinity of the opening of the second orifice passage in the intermediate chamber is large and the fluid flow in a position away from the opening is small. As a result, when vibration is input between the first mounting member and the second mounting member, a pressure fluctuation in the intermediate chamber is locally generated, and the intermediate chamber is caused by the pressure difference of the fluid flow. As a result, it has become possible to obtain an estimated view that a movable member constituting a part of the wall portion of the wall portion will not be stably displaced or deformed in a predetermined direction (for example, a vibration input direction). This means that when vibration is input in the tuning frequency range of the second orifice passage, the fluid flow amount through the second orifice passage is not sufficiently ensured, and the vibration isolation performance based on the orifice effect is hardly exhibited. It can be understood from things.

  The features of the present invention made to solve the above-described problems are as follows. 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.

(Aspect 1 of the present invention)
A feature of aspect 1 of the present invention is that 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 a wall portion is configured by the main rubber elastic body. And a flexible membrane that forms a part of the wall portion and encloses an incompressible fluid in each of the pressure receiving chamber and the equilibrium chamber, and communicates the pressure receiving chamber with the equilibrium chamber. In the fluid-filled vibration isolator provided with the orifice passage, an intermediate chamber filled with an incompressible fluid is formed, and a predetermined amount of displacement or deformation is allowed between the intermediate chamber and the pressure-receiving chamber. In this manner, a movable member that restricts the pressure fluctuation between the pressure receiving chamber and the intermediate chamber is disposed to form a second orifice passage that communicates the intermediate chamber with the equilibrium chamber, Tune the second orifice passage to a higher frequency range than the first orifice passage While there said second orifice passage in the fluid filled type vibration damping device allowed the opening at a plurality of positions relative to the intermediate chamber.

  In the fluid-filled vibration isolator having the structure according to this aspect, when the low-frequency and large-amplitude vibration is input, the deformation amount or the displacement amount of the movable member is limited, so that the first through the first orifice passage. Therefore, the vibration isolation effect based on the resonance action of the fluid flowing through the first orifice passage is effectively exhibited. In addition, when vibration is input in a higher frequency range and with a smaller amplitude, the pressure fluctuation of the pressure receiving chamber is exerted on the second orifice passage based on deformation or displacement of the movable member, and the relative pressure between the pressure receiving chamber and the equilibrium chamber is Fluid flow through the second orifice passage is generated based on the typical pressure fluctuation. And the anti-vibration effect based on the resonance effect | action of the fluid which is made to flow through the 2nd orifice channel | path will be exhibited.

  In this aspect, since the second orifice passage is opened at a plurality of locations in the intermediate chamber, the second orifice passage is opened at one location in the intermediate chamber as in the conventional structure. In contrast, the pressure and fluid flow exerted on the intermediate chamber through the second orifice passage are exerted over a wide area of the intermediate chamber. As a result, the pressure of the pressure receiving chamber can be applied to one surface, and the pressure applied to both surfaces can be equalized with respect to the movable member in which the pressure of the intermediate chamber is applied to the other surface. Thus, the displacement or deformation of the movable member can be stably and effectively expressed.

  Thereby, at the time of vibration input in the tuning frequency region of the second orifice passage, the fluid pressure fluctuation that acts on the second orifice passage from the pressure receiving chamber based on the displacement or deformation of the movable member is stabilized, Therefore, the fluid flow amount through the second orifice passage is advantageously ensured, and the desired vibration isolation effect based on the resonance action of the fluid flowing through the second orifice passage is effectively exhibited.

  In addition, the specific shape and structure of the 2nd orifice channel | path in this aspect are not limited. For example, a second orifice passage extending between the intermediate chamber and the equilibrium chamber may be branched at the intermediate portion in the length direction and opened at a plurality of locations in the intermediate chamber. Or the structure like the aspect 2 described below is also employ | adopted suitably.

(Aspect 2 of the present invention)
A feature of aspect 2 of the present invention is that, in the fluid filled type vibration damping device according to aspect 1 of the present invention, the second orifice passage extends in parallel across the intermediate chamber and the equilibrium chamber. The reason is that a plurality are formed.

  In this embodiment, since the plurality of second orifice passages are formed independently of each other, it is easy to set the effective sectional area of the second orifice passage large. In addition, since the formation space of the second orifice passage can be designed independently, a large degree of design freedom or layout freedom of the first and second orifice passages can be ensured. Also in this aspect, the second orifice passages formed in parallel may be branched in the middle, thereby setting the number of openings to the intermediate chamber to three or four or more. It becomes easy. However, in the second orifice passage having a single flow path structure that does not branch in the middle, there is an advantage that the pressure loss, that is, the flow resistance associated with the branching can be avoided as compared with the case of branching in the middle.

(Aspect 3 of the present invention)
A feature of aspect 3 of the present invention is that in the fluid-filled vibration isolator according to aspect 1 or 2 of the present invention, the opening of the second orifice passage to the intermediate chamber is defined as an outer peripheral portion of the movable member. In the peripheral wall portion of the intermediate chamber located in the circumferential direction, it is positioned at substantially equal intervals in the circumferential direction.

  In this embodiment, the pressure and fluid flow can be made more uniform in the intermediate chamber, and the displacement or deformation of the movable member can be further stabilized and the vibration isolation effect by the second orifice passage can be improved. And stabilization can be realized more effectively.

(Aspect 4 of the present invention)
The aspect 4 of the present invention is characterized in that in the fluid filled type vibration damping device according to any one of the aspects 1 to 3 of the present invention, the fluid filled type vibration damping device is disposed so as to constitute a part of the wall portion of the intermediate chamber. Further, there is provided a pressure adjusting rubber plate for adjusting the pressure fluctuation in the intermediate chamber by elastic deformation.

  In this embodiment, a pressure absorbing function is imparted to the intermediate chamber by the elastic deformation action of the pressure adjusting rubber plate. Therefore, by appropriately adjusting the spring specification of the pressure adjusting rubber plate, the pressure fluctuation of the pressure receiving chamber at the time of vibration input in a higher frequency range than the tuning frequency of the second orifice passage is changed to the displacement of the movable member. It can be applied to the intermediate chamber based on the deformation and absorbed based on the elastic deformation of the pressure-regulating rubber plate. As a result, it is possible to reduce or avoid a significant increase in the dynamic spring at the time of vibration input in a higher frequency range than the tuning frequency of the second orifice passage, and to improve the vibration isolation performance.

(Aspect 5 of the present invention)
A feature of aspect 5 of the present invention is that, in the fluid filled type vibration damping device according to aspect 4 of the present invention, the intermediate rubber plate for sandwiching the pressure regulating rubber plate constituting a part of the wall portion of the intermediate chamber The equilibrium chamber is formed on the opposite side of the chamber.

  In this embodiment, elastic deformation of the pressure adjusting rubber plate can be allowed in the equilibrium chamber. Therefore, in this aspect, each partition wall between the pressure receiving chamber and the equilibrium chamber in the intermediate chamber is configured by using the movable member and the pressure adjusting rubber plate, and thereby the pressure receiving chamber, the intermediate chamber, and the equilibrium chamber are formed. Therefore, it can be realized with a simple and compact structure as a whole.

(Aspect 6 of the present invention)
A feature of the sixth aspect of the present invention is that in the fluid filled type vibration damping device according to the fourth aspect of the present invention, the intermediate rubber plate for sandwiching the pressure adjusting rubber plate that constitutes a part of the wall portion of the intermediate chamber The air chamber is formed on the opposite side to the chamber.

  In this embodiment, the elastic deformation of the pressure adjusting rubber plate is allowed by the air chamber. Further, by adjusting or controlling the pressure of the air chamber, it is possible to control the spring characteristics of the pressure adjusting rubber plate. Thereby, by increasing the spring rigidity of the pressure adjusting rubber plate, the pressure absorbing action of the intermediate chamber based on the elastic deformation of the pressure adjusting rubber plate is reduced or canceled, or by reducing the spring rigidity of the pressure adjusting rubber plate. The pressure absorbing action of the intermediate chamber based on the elastic deformation of the pressure regulating rubber plate can be greatly exerted.

  Therefore, for example, at the time of vibration input in the tuning frequency range of the second orifice passage, a large negative pressure or positive pressure is exerted on the air chamber, and a restraining force is exerted on the pressure adjusting rubber plate, so that the second orifice passage flows. A sufficient amount of fluid flow can be secured to further improve the vibration isolation effect based on the fluid flow action of the fluid. Further, for example, at the time of vibration input in the frequency range exceeding the tuning frequency of the second orifice passage, by allowing the elastic deformation of the pressure adjusting rubber plate by releasing the air chamber to the atmosphere, etc., through the movable member The pressure fluctuation of the pressure receiving chamber exerted on the intermediate chamber can be absorbed by the elastic deformation of the pressure adjusting rubber plate, thereby reducing or avoiding the deterioration of the vibration isolation performance due to the high dynamic spring.

(Aspect 7 of the present invention)
A feature of aspect 7 of the present invention is that in the fluid filled type vibration damping device according to aspect 6 of the present invention, a pneumatic passage connected to the air chamber is provided, and the air chamber is passed through the pneumatic passage. There is a pressure adjusting means for adjusting the pressure from the outside.

  In this embodiment, by adjusting the pressure of the air chamber according to the vibration to be damped, various vibration proof characteristics that are exhibited based on the pressure adjustment of the air chamber as described above are selectively expressed. It becomes possible to make it. Therefore, for example, when the vibration to be damped changes, such as in an automobile engine mount, it is possible to obtain a more effective vibration proofing effect against a plurality of vibrations.

  Further, for example, by causing the air pressure fluctuation of the frequency corresponding to the frequency of the vibration to be vibration-proofed to act on the air chamber in consideration of the phase of the vibration to be vibration-proof, the pressure fluctuation generated in the intermediate chamber is allowed to move. You may make it act on a pressure receiving chamber via. By actively controlling the pressure fluctuation in the pressure receiving chamber in this manner, it is possible to obtain a vibration-proofing effect that is positive or counterbalanced against the input vibration.

(Aspect 8 of the present invention)
A feature of aspect 8 of the present invention is that in the fluid-filled vibration isolator according to any one of aspects 1 to 7 of the present invention, the second mounting member has a cylindrical shape, and the second mounting member One of the second mounting members is formed by disposing the first mounting member at one opening portion side of the first mounting member and connecting the first mounting member and the second mounting member with the main rubber elastic body. A partition member supported by the second mounting member while the other opening of the second mounting member is fluid-tightly covered with the flexible membrane. It is disposed between the opposing surface of the main rubber elastic body and the flexible membrane, the equilibrium chamber is formed between the opposing surface of the partition member and the flexible membrane, and further, the inside of the partition member An intermediate chamber is formed, and the first orifice passage and the second orifice are utilized using the partition member. To form a scan path, lies in the disposing the movable member relative to the partition member.

  In this aspect, the pressure receiving chamber and the equilibrium chamber can be efficiently formed on both sides of the partition member provided with the movable member, and a compact vibration isolator is realized as a whole. As a result, for example, the present invention can be suitably employed for an engine mount for automobiles, for example, where the installation space tends to be limited.

  As is clear from the above description, in the fluid-filled vibration isolator constructed according to the present invention, the opening of the second orifice passage is provided at a plurality of locations in the intermediate chamber, so that the pressure in the intermediate chamber is increased. The variation is made uniform, and the displacement or deformation of the movable member is stably generated. As a result, when vibration in the tuning frequency range of the second orifice passage is input, the pressure is efficiently and stably transmitted from the pressure receiving chamber to the intermediate chamber based on the displacement or deformation of the movable member. In addition, the fluid flow through the second orifice passage can be generated efficiently and stably, and the intended vibration isolation effect based on the resonance action of the fluid flowing through the second orifice passage is effectively exhibited. To get.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described. First, FIG. 1 shows an automobile engine mount 10 as an embodiment of 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 connected by a main rubber elastic body 16. The engine mount 10 has the first mounting bracket 12 attached to the power unit side, while the second mounting bracket 14 is attached to the body side, so that the power unit is mounted on the body to other engine mounts (not shown). It has come to support the anti-vibration in cooperation with. In this mounted state, the first mounting bracket 12 and the second mounting bracket 14 are attached to the engine mount 10 as the main rubber elastic body 16 is elastically deformed by the input of the shared load of the power unit. The main vibration to be vibrated is moved substantially in the vertical direction in FIG. 1 with respect to the space between the first mounting bracket 12 and the second mounting bracket 14 while being relatively displaced in the vertical direction by a predetermined amount. Will be entered. In addition, the engine mount 10 of this embodiment has the mount center axis (the center axis of the first and second mounting brackets 12 and 14) in a substantially vertical direction as shown in FIG. Therefore, in the following description, unless otherwise specified, the vertical direction in FIG. 1 is the vertical direction.

  More specifically, the first mounting member 12 has a substantially inverted cup shape, and a nut portion 18 extending upward (upward in FIG. 1) is integrally formed at the central portion thereof. The first mounting bracket 12 is attached to the power unit side by a fixing bolt (not shown) that is screwed onto the nut portion 18.

  Further, the second mounting bracket 14 has a large-diameter substantially stepped cylindrical shape, with the upper portion being a large-diameter portion 22 across a step portion 20 formed in an intermediate portion in the axial direction. The lower part is a small diameter part 24. In addition, the first mounting bracket 12 and the second mounting bracket 14 are spaced apart in the axial direction so that the central axes of both the brackets 12 and 14 are positioned substantially on the same line. A main rubber elastic body 16 is disposed between the second mounting brackets 14.

  The main rubber elastic body 16 has a large-diameter substantially truncated cone shape and is provided with a large-diameter recess 26 having a substantially inverted mortar shape that opens to the large-diameter end face. The first mounting member 12 is disposed on the same central axis as the main rubber elastic body 16 and is vulcanized and bonded in a state of being inserted axially downward from the end surface on the small diameter side of the main rubber elastic body 16. Further, the outer peripheral surface of the large-diameter side end portion of the main rubber elastic body 16 is vulcanized and bonded to the inner peripheral surface of the large-diameter portion 22 of the second mounting bracket 14. In short, the main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting bracket 12 and the second mounting bracket 14. Thus, the first mounting bracket 12 and the second mounting bracket 14 are disposed apart from each other so as to be positioned on substantially the same central axis extending in the main input direction of vibration to be damped. And elastically connected by the main rubber elastic body 16. In addition, since the large-diameter portion 22 of the second mounting bracket 14 is fixed to the main rubber elastic body 16, one opening (upper in FIG. 1) of the second mounting metal 14 is the main rubber elastic body. 16 is closed fluid-tightly. Further, a seal rubber layer 28 integrally formed with the main rubber elastic body 16 is attached to the inner peripheral surface of the second mounting bracket 14 such as the small diameter portion 24.

  Further, in the integrally vulcanized molded product of the main rubber elastic body 16 provided with the first and second mounting brackets 12 and 14, from the other opening side of the second mounting bracket 14 (lower side in FIG. 1). A partition member 30 is assembled.

  The partition member 30 is formed using a hard material such as a metal material or a synthetic resin material, and includes an upper partition metal fitting 32 and a lower partition metal fitting 34 having a thick, substantially disk shape. The upper partition metal fitting 32 and the lower partition metal fitting 34 are overlapped in the axial direction and inserted into the small diameter portion 24 of the second mounting bracket 14, and the small diameter portion 24 is subjected to diameter reduction processing such as an eight-way drawing. ing. Further, an upper locking groove 36 extending in the circumferential direction with a predetermined length is formed in the outer peripheral portion above the lower partition metal fitting 34, while the lower end portion of the small diameter portion 24 extends inward in the radial direction. A locking projection 38 is integrally formed, and the locking projection 38 is locked in the upper locking groove 36 when the diameter of the second mounting bracket 14 is reduced. Thereby, the partition member 30 is fixed to the second mounting bracket 14 so as to expand in the direction perpendicular to the axis, and the outer peripheral surface of the upper partition bracket 32 is attached to the inner peripheral surface of the second mounting bracket 14. Further, the second mounting bracket 14 is fluidly overlapped with the inner peripheral surface of the second mounting bracket 14 through the sealing rubber layer 28. In addition, a diaphragm 40 as a flexible film is assembled to the lower end portion of the partition member 30.

  The diaphragm 40 is constituted by a thin, substantially disk-shaped rubber elastic film that is easily deformed by having a sufficient slack in the center portion. Further, a large-diameter, generally annular fixing bracket 42 is vulcanized and bonded to the outer peripheral edge of the diaphragm 40. The fixing bracket 42 is extrapolated to the lower partition bracket 34 of the partition member 30 and the fixing bracket 42 is subjected to diameter reduction processing such as an eight-way drawing. A locking projection 44 extending radially inward is integrally formed at the upper end portion of the fixing bracket 42, while the outer peripheral portion below the lower partitioning bracket 34 has a predetermined length in the circumferential direction. An extending lower locking groove 46 is formed, and the locking projection 44 of the fixing bracket 42 is locked to the lower locking groove 46 of the lower partition fitting 34 when the diameter of the fixing bracket 42 is reduced. Thereby, in addition to the diaphragm 40 being fixed to the partition member 30 and the second mounting member 14, the outer peripheral surface of the lower partition member 34 is integrally formed with the diaphragm 40, so It is fluid-tightly superimposed on the inner peripheral surface of the fixture 42 through a seal rubber layer 48 attached to the peripheral surface. In other words, the other opening (lower in FIG. 1) of the second mounting bracket 14 is covered fluid-tightly with the diaphragm 40 via the partition member 30, and the partition member 30 is made of the main rubber elastic body 16. And between the opposing surfaces of the diaphragm 40 in the axial direction (up and down in FIG. 1).

  An incompressible fluid is sealed in a region between the opposing surfaces of the main rubber elastic body 16 and the diaphragm 40 that are sealed with respect to the external space, thereby defining a fluid sealing region. For example, water, alkylene glycol, polyalkylene glycol, silicone oil or the like is employed as such a sealed fluid. In order to effectively obtain a vibration-proofing effect based on the resonance action of the fluid, for example, 0.1 Pa · s or less. It is desirable to employ a low viscosity fluid. The incompressible fluid is sealed by, for example, assembling the partition member 30 and the diaphragm 40 to the integrally vulcanized molded product of the main rubber elastic body 16 including the first and second mounting brackets 12 and 14. It is realized by performing in the inside.

  Further, the fluid sealing region is divided into two in the vertical direction by arranging the partition member 30 so as to expand in the direction perpendicular to the axis. Accordingly, a part of the wall portion is configured by the main rubber elastic body 16 on one side (upper in FIG. 1) in the axial direction across the partition member 30, and the first mounting bracket 12 and the second mounting bracket 12 A pressure receiving chamber 50 is formed in which pressure fluctuations are caused by elastic deformation of the main rubber elastic body 16 when vibration is input between the mounting brackets 14. On the other hand, on the other side in the axial direction with respect to the partition member 30 (downward in FIG. 1), a part of the wall portion is constituted by the diaphragm 40, and the volume change is easy based on the elastic deformation of the diaphragm 40. An allowable equilibrium chamber 52 is formed. Note that a lower recess 54 that opens to the center portion is formed on the lower end surface of the lower partition fitting 34, and the volume of the equilibrium chamber 52 is advantageously secured in the lower recess 54. .

  In addition, a central recess 56 that opens to the center of the lower surface is formed in the upper partition member 32. The opening of the central recess 56 is covered with the lower partition fitting 34 by the upper partition fitting 32 and the lower partition fitting 34 being overlapped with each other in the axial direction. Further, an annular support protrusion 58 is projected from the center upper surface of the lower partition member 34 and is positioned inward of the opening of the center recess 56.

  A rubber elastic plate 60 having a substantially disk shape as a pressure adjusting rubber plate is disposed in the central recess 56 of the partition member 30. An annular fitting ring 62 is vulcanized and bonded to the outer peripheral surface of the rubber elastic plate 60. The fitting ring 62 is extrapolated to the support protrusion 58 of the lower partition metal fitting 34, and the lower end portion of the fitting ring 62 bent inward in the radial direction is formed in a circumferential groove provided in the support protrusion 58. While being locked and fixed, the fitting ring 62 is press-fitted and fixed in the central recess 56 of the upper partition fitting 30. That is, the rubber elastic plate 60 is arranged so as to expand in the direction perpendicular to the axis near the opening of the central recess 56, and the vicinity of the opening of the central recess 56 is fluid-tightly partitioned by the rubber elastic plate 60. As a result, a working air chamber 64 as an air chamber partitioned fluid-tightly from the pressure receiving chamber 50 and the equilibrium chamber 52 is formed in the central recess 56 between the rubber elastic plate 60 and the lower partitioning bracket 34. Yes.

  In addition, an air passage 66 is formed in the lower partition member 34, one end of the air passage 66 is connected to the working air chamber 64, and the other end is an outer periphery of the lower partition member 34. An opening is formed in the exposed port portion 68 formed on the surface. When the mount is mounted on the vehicle, the pressure of the working air chamber 64 can be adjusted from the outside through the air passage 66 from the air conduit 70 by connecting the air conduit 70 to the port portion 68. It can be done. The pneumatic passage according to the present embodiment includes an air passage 66 and an air pipe 70.

  Further, an annular fitting cylinder portion 72 extending upward is integrally formed on the central upper surface of the upper partition member 32. The fitting cylinder part 72 is press-fitted and fixed to a cover plate metal fitting 74 having a shallow, substantially inverted cup shape, and the opening portion of the fitting cylinder part 72 is covered with the cover plate metal fitting 74. As a result, a constraining arrangement region 76 is formed between the upper partition member 32 and the cover plate member 74 whose outer peripheral wall portion is constituted by the fitting tube portion 72. That is, the upper partition fitting 32 and the cover plate fitting 74 including the fitting tube portion 72 are configured as a restraint support housing having a restraint arrangement region 76 therein. In addition, the upper partition fitting 32 and the cover plate fitting 74 are provided with through holes 78 made up of a large number of small holes at each central portion constituting the upper and lower wall portions of the restraint support housing.

  A movable plate rubber 80 having a substantially disk shape, which is a movable plate as a movable member, is accommodated and disposed in the restraining arrangement region 76. The movable rubber plate 80 has a thickness dimension that is smaller than the upper and lower inner dimensions of the restraining arrangement region 76 and an outer diameter dimension that is smaller than the left and right inner dimensions of the restraining arrangement area 76. ing. Accordingly, the movable rubber plate 80 can be displaced in the vertical direction in the restraint arrangement region 76. Further, the movable plate rubber 80 abuts against the upper partition metal fitting 32 and the cover plate metal piece 74, so that the axial displacement amount of the movable plate rubber 80 is limited in a buffering manner together with its own elastic deformation action. It is like that.

  In addition, one surface of the movable rubber plate 80 faces the pressure receiving chamber 50 through a through hole 78 formed in the cover plate metal member 74, and the other surface of the movable rubber plate 80 is a central portion of the upper partition metal member 32. In other words, it faces the central recess 56 through a through hole 78 formed in the upper bottom portion of the central recess 56. Accordingly, the movable plate rubber 80 constitutes a part of the wall portion of the pressure receiving chamber 50, and is located in the central recess 56 of the partition member 30 on the side opposite to the pressure receiving chamber 50 across the movable plate rubber 80. , An intermediate chamber 82 is formed. The intermediate chamber 82 is formed between the opposed surfaces of the movable rubber plate 80 and the rubber elastic body 60 in the central recess 56, and an incompressible fluid is contained therein as in the pressure receiving chamber 50 and the equilibrium chamber 52. It is enclosed. Then, the movable rubber plate 80 is displaced in the plate thickness direction (up and down in FIG. 1) in the restraining arrangement region 76, so that the pressure receiving chamber 50 and the intermediate chamber are based on the fluid flow action through each through hole 78. Pressure is transmitted between 82. The amount of pressure transmission is limited based on the fact that the movable plate rubber 80 is brought into contact with the upper partition metal fitting 32 and the cover plate metal fitting 74 and the displacement amount of the movable plate rubber 80 is restricted.

  In addition, a meandering circumferential groove 84 extending in the circumferential direction with a predetermined length is formed in the outer peripheral portion of the upper partition metal fitting 32. The circumferential groove 84 is fluid-tightly covered with the second mounting bracket 14 with the seal rubber layer 28 attached to the inner peripheral surface of the second mounting bracket 14 interposed therebetween, whereby the first orifice passage 86 is covered. Is formed.

  In particular, in the present embodiment, a pair of circumferential grooves 84 constituting the first orifice passage 86 are provided in the upper partition fitting 32 as shown in FIGS. , 84 are opposed to each other in one radial direction across the central axis of the partition member 30. That is, the first orifice passage 86 is configured to include a pair of fluid flow paths in which circumferential grooves 84 formed independently of the partition member 30 are covered with the second mounting bracket 14. is there. Although not particularly limited, the fluid flow path formed by each circumferential groove 84 is formed by reciprocating in the circumferential direction at a portion extending over approximately ¼ circumference on the circumference of the partition member 30.

  In addition, one end of each fluid flow path constituting the first orifice passage 86 is connected to the pressure receiving chamber 50 through a communication window 88 that is opened radially outwardly at the upper end of the upper partition 32. ing. Further, the other end portion of each fluid flow path is connected to the equilibrium chamber 52 through a communication hole 90a penetrating the outer peripheral portion of the lower partition metal fitting 32 as shown in FIG. Thus, the pressure receiving chamber 50 and the equilibrium chamber 52 are connected to each other by the first orifice passage 86 including a pair of fluid flow paths, and the first orifice passage 86 is connected between the two chambers 50 and 52. Fluid flow through is allowed. In short, a pair of first orifice passages 86 are formed in parallel across the pressure receiving chamber 50 and the equilibrium chamber 52.

  Further, the resonance frequency of the fluid that is allowed to flow through the first orifice passage 86 is effective against vibrations in a low frequency range of about 10 Hz, which corresponds to an engine shake or the like based on the resonance action of the fluid. It is tuned so that the damping effect is demonstrated.

  Further, a concave groove 92 is formed in a portion of the upper partition 32 where the peripheral groove 84 is not formed. The concave groove 92 extends in a tunnel shape at the outer peripheral portion of the upper partition fitting 32 positioned on the outer peripheral side of the intermediate chamber 82, and the upper portion of the concave groove 92 extends in the radial direction of the upper partition fitting 32. A lower portion of 92 extends in the axial direction of the upper partition member 32. One end portion of the concave groove 92 is opened in the intermediate chamber 82, and the other end portion is connected to the equilibrium chamber 52 through communication holes 90 b and 90 b penetrating the outer peripheral portion of the lower partition metal fitting 32. It is connected. Thus, a second orifice passage 94 is formed, and the intermediate chamber 82 and the equilibrium chamber 52 are communicated with each other through the second orifice passage 94.

  In particular, in the present embodiment, the circumferential length of each communication hole 90 provided in the outer peripheral portion of the lower partition metal fitting 32 is the end of the circumferential groove 84 formed in the lower end portion of the upper partition metal fitting 30 or a concave groove. It is made larger than the circumferential length of the end portion of 92. Further, these four communication holes 90a, 90a, 90b, 90b in the lower partition metal fitting 32 are positioned at substantially equal intervals in the circumferential direction.

  Here, a pair of concave grooves 92 constituting the second orifice passage 94 are provided in the upper partition metal fitting 32. The pair of concave grooves 92, 92 are formed in a part of the partition member 30 excluding the part where the pair of circumferential grooves 84, 84 are formed, and are opposed to each other in one radial direction across the central axis of the partition member 30. ing. In other words, the second orifice passage 94 is configured to include a pair of fluid flow paths formed of concave grooves 92 that are independently formed with respect to the partition member 30.

  Accordingly, a pair of second orifice passages 94 are formed in parallel across the intermediate chamber 82 and the equilibrium chamber 52, and openings 96, 96 of the second orifice passage 94 with respect to the intermediate chamber 82 are The partition members 30 are opposed to each other in the radial direction across the central axis. In other words, the openings 96, 96 of the second orifice passage 94 to the intermediate chamber 82 are positioned at equal intervals of approximately half the circumferential length of the partition member 30.

  Further, the resonance frequency of the fluid flowing through the second orifice passage 94 is tuned to a medium frequency range of about 20 to 40 Hz corresponding to idling vibration or the like based on the resonance action of the fluid. As a result, the second orifice passage 94 is tuned to a higher frequency range than the first orifice passage 86, and the resonance of the fluid that causes the second orifice passage 94 to flow at the time of vibration input in the middle frequency range. Based on the action, an effective anti-vibration effect (vibration insulation effect by the low dynamic spring) is exhibited.

  The tuning of the first and second orifice passages 86 and 94 corresponds to, for example, the rigidity of the wall springs of the pressure receiving chamber 50, the equilibrium chamber 52, and the intermediate chamber 82 (the amount of pressure change required to change only the unit volume). In consideration of the characteristic value), etc., it is possible to adjust the passage length and the passage cross-sectional area of each of the orifice passages 86 and 94. The frequency at which the phase changes and becomes a substantially resonant state can be grasped as the tuning frequency of the orifice passages 86 and 94.

  Further, in the engine mount 10 having the above-described structure, the air pipe 70 is connected to the port portion 68 of the air passage 66 formed in the partition member 30 in a state where the engine mount 10 is mounted on an automobile. The working air chamber 64 is connected to the switching valve 98 through 70. The switching valve 98 is constituted by, for example, an electromagnetic valve or the like, and allows the working air chamber 64 to selectively communicate with the atmosphere and a predetermined negative pressure source. Then, by appropriately switching and controlling the switching valve 98 according to the running state of the automobile, the engine mount 10 can obtain an effective vibration-proofing effect against vibrations input under various conditions.

  The switching valve 98 is connected to a control device (not shown). In this control device, necessary information is inputted from various sensors provided in the vehicle, among various information representing the state of the vehicle, such as the vehicle speed, the engine speed, the reduction gear selection position, and the throttle opening. Based on such information, the switching valve 98 is switched by microcomputer software or the like according to a preset program. As is clear from the above description, in this embodiment, the pressure adjusting means for adjusting the pressure of the working air chamber 64 from the outside includes the switching valve 98 and the control device.

  One of the specific operation | movement aspects in the engine mount 10 made into such a structure is shown. There are three types of vibration that should be isolated: (1) engine shake, which is low-frequency, large-amplitude vibration, (2) running noise, which is high-frequency, small-amplitude vibration, and (3) idling vibration, which is medium-frequency, medium-amplitude vibration. The anti-vibration effect for each vibration will be described below.

(1) Anti-vibration effect against engine shake When a low-frequency large-amplitude vibration such as an engine shake is input, a pressure fluctuation with a very large amplitude is induced in the pressure receiving chamber 50. The movable rubber plate 80 is displaced during the pressure fluctuation, but the movable rubber plate 80 is movable so that the pressure fluctuation in the pressure receiving chamber 50 cannot be effectively absorbed by the displacement of the movable movable range of the movable rubber plate 80. The distance is set. As a result, the pressure absorbing action of the movable rubber plate 80 cannot substantially function, and effective pressure fluctuations are generated in the pressure receiving chamber 50.

  That is, the movable rubber plate 80 and the intermediate chamber 82 can hardly function when inputting low-frequency large-amplitude vibration. Under such a state, the fluid flow amount through the first orifice passage 86 can be effectively ensured by the relative pressure fluctuation generated between the pressure receiving chamber 50 and the equilibrium chamber 52 at the time of vibration input. An anti-vibration effect (high damping effect) effective against the engine shake is exhibited based on the resonance action of the fluid flowing through one orifice passage 86. Note that the anti-vibration effect against low-frequency, large-amplitude vibrations has almost no action of the intermediate chamber 82, and therefore the working air chamber 64 may be connected to either the atmosphere or a negative pressure source.

(2) Anti-vibration effect against traveling boom noise, etc. When a high frequency small amplitude vibration such as a running boom noise higher than the tuning frequency of the second orifice passage 94 is input, a pressure fluctuation with a small amplitude is induced in the pressure receiving chamber 50. The Rukoto. The movable rubber plate 80 is effectively displaced during the pressure fluctuation, and the pressure fluctuation of the pressure receiving chamber 50 is efficiently transmitted to the intermediate chamber 82 due to the displacement of the movable distance range of the movable rubber plate 80. The hydraulic pressure absorbing action based on the elastic deformation of the rubber elastic plate 60 is exhibited. In short, when a high frequency small amplitude vibration is input, the hydraulic pressure absorption function by the cooperative action of the movable rubber plate 80, the intermediate chamber 82 and the rubber elastic plate 60 functions, and the pressure fluctuation in the pressure receiving chamber 50 is absorbed by the intermediate chamber 82. As a result, the mount 10 can be prevented from having a highly dynamic spring.

  Note that when the high frequency small amplitude vibration is input, the first orifice passage 86 and the second orifice passage 94 tuned to a lower frequency range have a remarkably large fluid flow resistance due to antiresonant action. Thus, the state is substantially closed.

  That is, under such a state, the pressure receiving chamber 50 and the intermediate chamber 82 from which the pressure is released are both in a disconnected state independent of the equilibrium chamber 52, but constitute a part of the wall portion of the intermediate chamber 82. The rubber elastic plate 60 is in a state in which elastic deformation is allowed relatively easily because the working air chamber 64 formed behind the rubber elastic plate 60 is released into the atmosphere. In particular, the rubber elastic plate 60 has a spring characteristic that is soft enough to sufficiently absorb the pressure fluctuation of the intermediate chamber 82 caused by the input of high-frequency small-amplitude vibration such as running-over noise. Is set.

  Therefore, the pressure fluctuation released from the pressure receiving chamber 50 to the intermediate chamber 82 at the time of vibration input is absorbed in the intermediate chamber 82 based on the elastic deformation of the rubber elastic plate 60. As a result, the first Significantly high dynamic spring due to substantial blockage of the first and second orifice passages 86 and 94 is avoided, and a good vibration isolation effect against high frequency small amplitude vibration (vibration insulation effect based on low dynamic spring characteristics) Is demonstrated.

(3) Anti-vibration effect against idling vibration When a medium frequency medium amplitude vibration such as idling vibration higher than the tuning frequency of the first orifice passage 86 is input, a pressure fluctuation with a certain amplitude is caused in the pressure receiving chamber 50. Will be. The movable plate rubber 80 is displaced during the pressure fluctuation, and the pressure fluctuation in the pressure receiving chamber 50 is transmitted to the intermediate chamber 82 due to the displacement of the movable distance range of the movable plate rubber 80. Note that when the medium frequency medium amplitude vibration is input, the first orifice passage 86 tuned to a lower frequency range has a significantly increased fluid flow resistance due to an anti-resonant action, and is substantially in a closed state. Is done.

  That is, under such a state, the intermediate chamber 82 in which effective pressure fluctuation is caused similarly to the pressure receiving chamber 50 and the variable volume equilibrium chamber 52 are connected through the second orifice passage 94 tuned to the middle frequency range. It becomes composition. Therefore, the fluid flow amount through the second orifice passage 94 can be effectively ensured by the relative pressure fluctuation generated between the pressure receiving chamber 50 and the intermediate chamber 82 and the equilibrium chamber 52 when the vibration is input. Based on the resonance action of the fluid flowing through the second orifice passage 94, an effective anti-vibration effect against the engine shake (vibration insulation effect based on the low dynamic spring characteristic) can be exhibited.

  Here, the lower partition metal fitting in which the opening 96 of the second orifice passage 94 with respect to the intermediate chamber 82 constitutes the peripheral wall portion of the intermediate chamber 82 located at the outer peripheral portion of the movable rubber plate 80, that is, the peripheral wall portion of the central recess 56. A pair is provided at positions facing each other in one radial direction around the peripheral wall portion of 34. As a result, when the medium frequency medium amplitude vibration is input, the opening 96 of the second orifice passage 94 is provided at a specific position in the peripheral wall portion of the intermediate chamber 82, and therefore, local to the intermediate chamber 82. Pressure fluctuations and fluid flow are avoided.

  As a result, the movable plate rubber 80 is displaced as a whole without being locally displaced, and the displacement of the movable plate rubber 80 is stabilized, and the pressure fluctuation of the pressure receiving chamber 50 is changed to the intermediate chamber. 82 and the balance chamber 52 are transmitted stably and efficiently. In short, when an intermediate frequency medium amplitude vibration is input, the movable rubber plate 80 can function effectively, and an effective pressure fluctuation is caused in the intermediate chamber 82 to which the pressure in the pressure receiving chamber 50 is transmitted.

  In the present embodiment, the working air chamber 64 may be connected to the atmosphere or connected to a negative pressure source at the time of vibration input in the tuning frequency region of the second orifice passage 94. . They can be set according to the required anti-vibration characteristics, or they may be switched appropriately.

  That is, in the present embodiment, the spring characteristic of the rubber elastic plate 60 that constitutes the wall portion of the intermediate chamber 82 when the working air chamber 64 is connected to the atmosphere and when it is connected to a negative pressure source. Changes. First, in a state where the working air chamber 64 is connected to the atmosphere, the rubber elastic plate 60 is brought into an unrestrained state, and a soft spring characteristic is exhibited. On the other hand, in a state in which the working air chamber 64 is connected to the negative pressure source, the rubber elastic plate 60 is negatively sucked and deformed toward the working air chamber 64 side, or is further strongly sucked, so that the rubber elastic plate 60 is bottom of the working air chamber 64. By being superposed on (the upper end surface of the lower partition metal fitting 34), deformation restraint is exerted, and hard spring rigidity is exhibited. Therefore, the wall spring stiffness of the intermediate chamber 82 is different between the case where the working air chamber 64 is connected to the atmosphere and the case where it is connected to the negative pressure source. As a result, the tuning frequency of the second orifice passage 94 is different. Changes, and the frequency at which an effective anti-vibration effect is exhibited changes. As is clear from this, the spring characteristic of the rubber elastic plate 60 is not as soft as that of the diaphragm 40, and is caused by the intermediate deformation caused by the input of medium frequency medium amplitude vibration such as idling vibration based on the elastic deformation. The spring 82 has a spring stiffness that does not absorb pressure fluctuations in the chamber 82 and that can cause pressure fluctuations sufficient to cause fluid flow through the second orifice passage 94 with respect to the intermediate chamber 82. .

  Therefore, for example, by switching the switching valve 98 between a normal idling state and a fat idling state such as when starting or operating an air conditioner, the working air chamber 64 is selectively connected to the atmosphere and the negative pressure source, Even in the middle frequency range, it is possible to tune the second orifice passage 94 to a higher degree against idling vibration having different frequencies in the range of several Hz to several tens of Hz, and to obtain a further excellent vibration isolation effect. It becomes.

  However, it is not essential in the present invention to change and set the tuning of the second orifice passage 94 by switching the switching valve 98 according to the vehicle state in the frequency range where idling vibration is generated. For example, when the amount of change in idling vibration is relatively small, the working air chamber 64 is always connected to the negative pressure source in the idling state, and the second orifice passage 94 is in this state. It is possible to obtain a more advanced anti-vibration effect by tuning so that the amount of fluid flow through can be ensured more advantageously, and a more effective anti-vibration effect can be exhibited against idling vibration. It is.

  In the present embodiment, as described above, since the plurality of openings 96 to the intermediate chamber 82 of the second orifice passage 94 are provided, the displacement of the movable rubber plate 80 is stabilized. As a means for stabilizing the displacement of the movable rubber plate 80, the distance between the cover plate metal member 74 and the upper partition metal member 32 that constitutes the upper and lower wall portions of the restraint arrangement region 76 is increased. It is not necessary to increase the stroke in the thickness direction of the movable rubber plate 80 by reducing the thickness of the movable rubber plate 80 or the like.

  Therefore, the maximum speed at the time of displacement of the movable rubber plate 80 is suppressed, and a large amplitude vibration such as when cranking the engine or overcoming a step is inputted to cause a sudden pressure fluctuation in the pressure receiving chamber 50. At this time, the generation of noise due to the movable plate rubber 80 being brought into contact with the restraining support housing is effectively suppressed.

  In addition, since the movable rubber plate 80 can be disposed in a compact manner, a large degree of freedom in designing the pressure receiving chamber 50, the intermediate chamber 82, the partition member 30, and the like is ensured.

  In the present embodiment, in the upper partition 32, the pair of peripheral grooves 84, 84 constituting the first orifice passage 86 at a position avoiding the pair of concave grooves 92, 92 constituting the second orifice passage 94. As a result, the circumferential length of the first orifice passage 86 is effectively ensured in the limited space of the upper partition 32. Therefore, the vibration isolation effect based on the fluid flow action through the first orifice passage 86 is more reliably obtained.

  Furthermore, in the present embodiment, the four communication holes 90a, 90a, 90b, 90b formed in the lower partition metal fitting 34 are positioned at substantially equal intervals in the circumferential direction, and the circumferential length of each communication hole 90 is Is larger than the circumferential length of the end of each of the first and second orifice passages 86, 94 on the side of each equilibrium chamber 52. Here, the upper partition 32 and the lower partition 34 are overlapped with each other, and the ends of the first and second orifice passages 86 and 94 are connected to the equilibrium chamber 52 through the communication holes 90 of the lower partition 34. At this time, the opening degree of the end of each orifice passage 86, 94 toward the equilibrium chamber 52 can be adjusted by relatively displacing the circumferential positions of the upper partition member 32 and the lower partition member 34. Therefore, the tuning frequency of each of the orifice passages 86 and 94 can be easily changed without a major design change in accordance with the difference in the model of the automobile or the required vibration isolation characteristics. It is possible to easily cope with the vibration characteristics.

  Further, in the above embodiment, the movable plate rubber 80 that is physically arranged independently from the upper and lower partition fittings 32 and 34 constituting the partition member 30 and can be freely displaced by a predetermined distance is employed as the movable member. Instead, the outer peripheral edge portion is fixed to the partition member, and displacement or deformation is allowed based on the elastic deformation of the central portion, thereby allowing the pressure transmission from the pressure receiving chamber to the intermediate chamber. It is also possible to employ a membrane. Since such a movable film has a known structure, a detailed description thereof will be omitted.

  As mentioned above, although one embodiment of the present invention has been described in detail, the present invention is not limited in any way by the specific description in the embodiment, and various changes, modifications, and modifications based on the knowledge of those skilled in the art. Needless to say, the present invention can be implemented in a mode with improvements and the like, and all such modes are included in the scope of the present invention without departing from the gist of the present invention.

  For example, in the embodiment described above, a pair of openings 96 for the intermediate chamber 82 of the second orifice passage 94 are provided in the peripheral wall portion of the intermediate chamber 82 and are positioned at substantially equal intervals in the circumferential direction. The number of openings of the second orifice passage 94 may be three or more, or a plurality of openings may be positioned at unequal intervals in the circumferential direction.

  In the above embodiment, the second orifice passage 94 is constituted by a pair of independently formed fluid flow paths. However, for example, a single fluid flow path is branched in the middle and a plurality of intermediate passages 82 are provided in the intermediate chamber 82. It is also possible to open at a location. The same applies to the first orifice passage 86.

  That is, the shape, size, structure, position, number, and the like of the first and second orifice passages 86 and 94 are set and changed according to required vibration-proof characteristics and manufacturability. However, the present invention is not limited to the examples.

  In the above embodiment, the mount anti-vibration characteristics are switched by selectively connecting the working air chamber 64 to the atmosphere and the negative pressure source by the switching valve 98. Effective anti-vibration effect for any of low-frequency large amplitude vibration, medium-frequency medium amplitude vibration, and high-frequency small amplitude vibration even in a state in which the air passage 66 is always connected to the atmosphere. Of course, can be exhibited.

  That is, the rubber elastic plate 60, the working air chamber 64, the switching valve 98, etc. are not necessarily provided. For example, an equilibrium chamber may be formed on the opposite side of the intermediate chamber 82 with the rubber elastic plate 60 constituting a part of the wall portion of the intermediate chamber 82 interposed therebetween.

  In the above-described embodiment, the movable plate rubber 80 has a thin and substantially disk shape. For example, one or more protrusions for buffering or positioning are provided on the surface of the movable plate rubber, or the movable plate rubber is provided. May be formed into a corrugated plate shape having a plurality of projections and depressions and spreading in a substantially wave shape.

  Furthermore, in the above embodiment, the gap is formed around the entire movable plate rubber 80 with the movable plate rubber 80 positioned at the center of the restraining arrangement region 76. May be assembled in a state in which they are elastically contacted in advance with a part of the constraining arrangement region 76 and further compressed in the plate thickness direction. That is, even if the movable rubber plate is assembled in a state of contact with the restraining arrangement region 76 in the thickness direction or in a compressed state, an elastic deformation of the movable rubber plate is caused by a pressure difference between the upper and lower surfaces of the movable rubber plate. Therefore, the pressure absorbing action of the pressure receiving chamber 50 can be exhibited. In addition, the impact of the movable plate rubber 80 against the partition member 30 or the like can be more advantageously suppressed by storing and assembling the movable plate rubber in the restrained arrangement region 76 in a contact state or a compressed state in advance. .

  In addition, in the above-described embodiments, specific examples of applying the present invention to the engine mount 10 for automobiles have been described. However, the present invention can prevent various vibration bodies other than automobiles other than automobile body mounts and differential mounts. Needless to say, any of the vibration mounts can be applied.

FIG. 3 is a longitudinal cross-sectional explanatory view showing an automobile engine mount as one embodiment of the present invention, corresponding to the II cross section of FIG. 2. It is a plane explanatory view showing the upper partition metal fitting which constitutes a part of the automobile engine mount in FIG. FIG. 3 is an explanatory bottom view showing an upper partition metal fitting in FIG. 2. It is bottom explanatory drawing which shows the partition member which comprises a part of engine mount for motor vehicles in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Automotive engine mount 12 1st attachment metal fitting 14 Second attachment metal fitting 16 Main body rubber elastic body 40 Diaphragm 50 Pressure receiving chamber 52 Equilibrium chamber 82 Intermediate chamber 86 First orifice passage 94 Second orifice passage 96 Opening portion

Claims (8)

While the first mounting member and the second mounting member are connected by a main rubber elastic body, 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 by a flexible membrane. A fluid-filled vibration isolator having a configured equilibrium chamber, in which an incompressible fluid is sealed in each of the pressure receiving chamber and the equilibrium chamber, and a first orifice passage communicating the pressure receiving chamber and the equilibrium chamber is provided. In
An intermediate chamber filled with an incompressible fluid is formed, and a predetermined amount of displacement or deformation is allowed between the intermediate chamber and the pressure receiving chamber, thereby allowing the pressure receiving chamber and the intermediate chamber to move between the pressure receiving chamber and the intermediate chamber. A movable member that restricts the pressure fluctuation is disposed to form a second orifice passage that communicates the intermediate chamber with the equilibrium chamber, and the second orifice passage is more than the first orifice passage. A fluid-filled vibration isolator characterized by tuning to a high frequency range and opening the second orifice passage at a plurality of locations with respect to the intermediate chamber.   The fluid-filled vibration isolator according to claim 1, wherein a plurality of the second orifice passages are formed in parallel across the intermediate chamber and the equilibrium chamber.   3. The fluid according to claim 1, wherein openings of the second orifice passage to the intermediate chamber are positioned at substantially equal intervals in a circumferential direction in a peripheral wall portion of the intermediate chamber located at an outer peripheral portion of the movable member. Enclosed vibration isolator.   The fluid according to any one of claims 1 to 3, further comprising a pressure-adjusting rubber plate that is disposed so as to constitute a part of a wall portion of the intermediate chamber and adjusts a pressure fluctuation of the intermediate chamber by elastic deformation. Enclosed vibration isolator.   5. The fluid filled type vibration damping device according to claim 4, wherein the equilibrium chamber is formed on the opposite side of the intermediate chamber with the pressure adjusting rubber plate constituting a part of the wall portion of the intermediate chamber interposed therebetween.   The fluid-filled vibration isolator according to claim 4, wherein an air chamber is formed on the opposite side of the intermediate chamber with the pressure adjusting rubber plate constituting a part of the wall portion of the intermediate chamber interposed therebetween.   7. The fluid filled type vibration damping device according to claim 6, wherein a pneumatic passage connected to the air chamber is provided, and pressure adjusting means for adjusting the pressure of the air chamber from the outside through the pneumatic passage is provided. .   The second mounting member has a cylindrical shape, and the first mounting member and the second mounting member are separated from each other by positioning the first mounting member at one opening side of the second mounting member. By connecting with the main rubber elastic body, one opening of the second mounting member is fluid-tightly covered and the other opening of the second mounting member is fluid-tight with the flexible membrane. A partition member that covers and is supported by the second mounting member is disposed between the opposing surfaces of the main rubber elastic body and the flexible membrane, and the opposing surfaces of the partition member and the flexible membrane are arranged. Forming the equilibration chamber therebetween, further forming the intermediate chamber inside the partition member, and forming the first orifice passage and the second orifice passage using the partition member; The flow according to any one of claims 1 to 7, wherein the movable member is disposed with respect to the partition member. Filled vibration damping device.

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