JP2006112607A - Fluid enclosed anti-vibrational device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid enclosed anti-vibrational device which is novel construction and can reduce or prevent extraordinary noise from occurring in the case of impulsively large vibration and load being applied while effectively securing anti-vibrational effect revealed based on fluidic action of enclosed incompressible fluid. <P>SOLUTION: The device provides a depressing means 92 which allows fluidic flow from a equilibrium chamber 46 to a pressure received chamber 44 by cooperatively working with an opening window 78 formed on a locked plate 58 of the pressure received chamber side in such condition that a movable plate 62 is restrained from displacing to the pressure received chamber 44 side by the locked plate 58 of the pressure received chamber side with respect to the movable plate 62 which is arranged to partition off the pressure received chamber 44 and the equilibrium chamber 46 and at the same time provides a fluidic flow obstruction part 80 which obstructs fluid from flowing from the pressure received chamber 44 through the depress means 92 to the equilibrium chamber 46 in such condition that a movable plate 62 is restrained from displacing to the equilibrium chamber 46 side by the locked plate 72 of the equilibrium chamber side with respect to the locked plate 72 of the equilibrium chamber side. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fluid-filled vibration isolator that obtains a vibration-proof effect based on the flow action of an incompressible fluid enclosed therein, and is suitably employed, for example, as an engine mount for an automobile. The present invention relates to a fluid-filled vibration isolator.

  Conventionally, an anti-vibration device in which a first attachment member and a second attachment member are connected by a main rubber elastic body as an anti-vibration coupling body or an anti-vibration support body interposed between members constituting a vibration transmission system. Is widely adopted in various fields, and as one type, the first mounting member and the second mounting member are connected by a main rubber elastic body, and a part of the wall portion is configured by the main rubber elastic body. A pressure receiving chamber in which a pressure fluctuation is generated when vibration is input between the mounting member and the second mounting member, and a part of the wall portion is configured by the flexible film, and the volume is based on the deformation of the flexible film. A fluid-filled type vibration isolator that forms an equilibrium chamber in which changes occur, encloses an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and has an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other Has been proposed.

  In such a fluid-filled vibration isolator, it is possible to obtain an anti-vibration effect using a fluid action such as a resonance action of the enclosed incompressible fluid, and only with the anti-vibration action of the main rubber elastic body. Low dynamic spring effects and high damping effects can be easily obtained in the tuning frequency range. For example, engine mounts and body mounts for automobiles that require high vibration isolation performance in a specific frequency range Application to is being considered.

  By the way, in an engine mount for automobiles, the frequency of vibrations to be vibrated may differ depending on the traveling state or the like. However, the anti-vibration effect exerted based on the resonance action of the fluid flowing through the orifice passage is limited to a relatively narrow frequency range in which the orifice passage is previously tuned. Therefore, in such a fluid-filled vibration isolator, when vibration in a frequency range higher than the tuning frequency of the orifice passage is input, the orifice passage is substantially closed, and thus, There is a problem that high vibration springs are generated and the vibration isolation performance is lowered.

  Therefore, in order to avoid a significantly high dynamic spring at the time of vibration input in a frequency range higher than the tuning frequency of the orifice passage and improve the vibration isolation performance, as described in Patent Document 1 and the like, the thickness direction The pressure receiving chamber and the equilibrium chamber are separated by a movable plate that is arranged so that it can be displaced by a small amount, and the displacement in the thickness direction of the movable plate based on the pressure difference between the pressure receiving chamber and the equilibrium chamber results in a frequency higher than the tuning frequency of the orifice passage A fluid-filled vibration isolator has been proposed in which minute pressure fluctuations in the pressure receiving chamber at the time of vibration input in the region are absorbed by the equilibrium chamber.

  By the way, in the fluid filled type vibration isolator, when a shocking large load vibration is input between the first mounting member and the second mounting member, shocking abnormal noise may occur. For example, when it is applied to an engine mount for automobiles, it has been confirmed that such an abnormal noise may be generated when the projection is passed over.

  The generation of such shocking abnormal noise is caused by excessive negative pressure generated in the pressure receiving chamber due to the excessive negative pressure generated by restricting the fluid flow through the orifice passage at the time of input of shocking heavy load vibration. This is considered to be caused by abnormal noise generated when the gas is separated and the gas is dissolved again in the sealed fluid.

  Therefore, in order to prevent the generation of the abnormal noise as described above, a device for quickly eliminating the excessive negative pressure generated in the pressure receiving chamber when a shocking large load vibration is input is required. It is.

  Patent Document 2 discloses a fluid-filled vibration isolator in which a cut is formed in an elastically deformable partition wall (movable plate) that separates a working chamber (pressure receiving chamber) and a compensation chamber (equilibrium chamber). Yes. In such a fluid-filled vibration isolator, the periphery of the notch formed in the partition wall (movable plate) is deformed based on the pressure difference between the working chamber (pressure receiving chamber) and the compensation chamber (equilibrium chamber). The fluid flow between the working chamber (pressure receiving chamber) and the compensation chamber (equilibrium chamber) is allowed, so that an excessively large load vibration is input, causing an excessive amount to be generated in the working chamber (pressure receiving chamber). It is thought that the negative pressure can be eliminated.

  However, in such a fluid-filled vibration isolator, not only when an excessive negative pressure is generated in the working chamber (pressure receiving chamber), but also when a positive pressure is generated, the partition wall (movable plate) ) May be deformed around the notch formed in the gas flow path, thereby causing fluid flow between the working chamber (pressure receiving chamber) and the compensation chamber (equilibrium chamber). As a result, the fluid flows in the orifice passage. It may be difficult to secure a sufficient amount of fluid to be squeezed, and it may be difficult to effectively obtain a target vibration-proofing effect.

Japanese Patent Publication No. 4-17291 Japanese Patent Publication No. 6-81972

  Here, the present invention has been made in the background of the circumstances as described above, and the problem to be solved is the vibration-proofing effect that is exhibited based on the flow action of the enclosed incompressible fluid. An object of the present invention is to provide a fluid-filled vibration isolator having a novel structure capable of reducing or preventing the generation of abnormal noise when shockingly large vibrations or loads are applied while ensuring effective.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  In the first aspect of the present invention, the first mounting member and the second mounting member are connected by a main rubber elastic body, and the main rubber elastic body constitutes a part of the wall portion so that pressure fluctuation occurs when vibration is input. A pressure receiving chamber that is formed, and an equilibrium chamber in which a part of the wall portion is made of a flexible film and volume change is allowed, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber; While providing an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other, a movable plate that divides the pressure receiving chamber and the equilibrium chamber is disposed so as to be minutely displaceable in the plate thickness direction. Based on the displacement in the plate thickness direction of the movable plate based on the pressure difference between the pressure receiving chamber and the equilibrium chamber exerted on the surface, the minute pressure fluctuation of the pressure receiving chamber at the time of vibration input is released to the equilibrium chamber and absorbed. In the fluid-filled vibration isolator, the displacement of the movable plate toward the pressure receiving chamber is restricted. A pressure receiving chamber side restraint plate and an equilibrium chamber side restraint plate that restrains the displacement of the movable plate toward the equilibrium chamber side, and an opening window is formed in each of the pressure receiving chamber side restraint plate and the equilibrium chamber side restraint plate. On the other hand, with respect to the movable plate, the movable plate cooperates with the opening window formed in the pressure receiving chamber side constraining plate in a state where the displacement of the movable plate to the pressure receiving chamber side is constrained by the pressure receiving chamber side constraining plate. Thus, a depressurizing means for allowing fluid flow from the equilibrium chamber to the pressure receiving chamber is provided, and the movable plate is moved to the equilibrium chamber side by the equilibrium chamber side constraint plate with respect to the equilibrium chamber side constraint plate. A fluid flow blocking portion is provided for blocking fluid flow from the pressure receiving chamber to the equilibrium chamber through the press-out means in a state where the displacement of the pressure is restricted.

  In the fluid-filled vibration isolator having the structure according to this embodiment, the pressure receiving chamber and the equilibrium chamber are formed through the opening window formed in the pressure receiving chamber side restraining plate and the opening window formed in the equilibrium chamber side restraining plate. Since they are in communication with each other, the pressure of the pressure receiving chamber is exerted on the surface of the movable plate on the side of the pressure receiving chamber, while the pressure of the equilibrium chamber is exerted on the surface of the movable plate on the side of the equilibrium chamber. When a pressure difference is generated between the pressure receiving chamber and the equilibrium chamber, a displacement in the thickness direction of the movable plate is generated.

  Therefore, in the fluid-filled vibration isolator according to this aspect, when a shocking large load vibration is input between the first mounting member and the second mounting member, the pressure receiving chamber is generated. The movable plate displaced to the pressure receiving chamber side by the excessive negative pressure is movable with the opening window formed on the pressure receiving chamber side restricting plate in a state where the displacement to the pressure receiving chamber side is restricted by the pressure receiving chamber side restricting plate. Since the fluid flow from the equilibrium chamber to the pressure receiving chamber is allowed by the cooperation of the pressure release means provided on the plate, the excessive negative pressure generated in the pressure receiving chamber can be quickly eliminated. It becomes possible to do.

  On the other hand, the movable plate displaced to the equilibrium chamber side when the vibration is input between the first mounting member and the second mounting member to raise the pressure in the pressure receiving chamber is balanced by the equilibrium chamber side restraining plate. In a state where the displacement toward the chamber is constrained, the fluid flow from the pressure receiving chamber through the depressurization means to the equilibrium chamber is blocked by a fluid flow blocking portion provided on the equilibrium chamber side restraining plate. Thus, when vibration is input between the first mounting member and the second mounting member, the pressure in the pressure receiving chamber can be sufficiently increased.

  Therefore, in the fluid filled type vibration damping device according to this aspect, when vibration is input between the first mounting member and the second mounting member and the pressure in the pressure receiving chamber is increased, the pressure in the pressure receiving chamber is increased. It is possible to effectively raise the anti-vibration effect that is exhibited based on the flow action of the enclosed incompressible fluid, while receiving a large amount of shock and large vibration and load. When an excessive negative pressure is generated in the chamber, the excessive negative pressure generated in the pressure receiving chamber is quickly eliminated, and abnormal noise caused by the excessive negative pressure generated in the pressure receiving chamber is generated. It can be reduced or prevented.

  Further, in this aspect, since the displacement of the movable plate is restrained by the pressure-receiving chamber-side restraint plate and the equilibrium chamber-side restraint plate, an excessive stress should not be generated on the movable plate. Is possible. Thereby, the durability of the movable plate can be advantageously ensured, and stable characteristics can be exhibited over a long period of time.

  In addition, the pressure release means in this aspect refers to the pressure receiving chamber from the equilibrium chamber in cooperation with the opening window formed in the pressure receiving chamber side restraint plate in a state where the displacement to the pressure receiving chamber side is restrained by the pressure receiving chamber side restraining plate. Any of various structures that allow fluid flow to the fluid can be employed. For example, in the case of a through-hole that penetrates the movable plate in the thickness direction, it may be always opened with a predetermined diameter or pierced with a needle. Thus, it may be a hole that is closed by elasticity and opens when hydraulic pressure acts. Alternatively, the fluid flow from the equilibrium chamber to the pressure receiving chamber can be controlled under certain conditions, such as an opening that is formed in the movable plate by deforming the notch or slit formed in the movable plate by the hydraulic pressure. An acceptable structure may be used.

  According to a second aspect of the present invention, in the fluid-filled vibration isolator according to the first aspect, the press-out means is provided in a central portion of the movable plate. In the fluid-filled vibration isolator having the structure according to this aspect, for example, even if the movable plate is arranged to be rotatable in the circumferential direction, it is formed on the pressure receiving chamber side restraint plate. The positioning of the opening window that allows fluid flow from the equilibrium chamber to the pressure receiving chamber by cooperating with the pressure release means provided on the movable plate and the pressure release means provided on the movable plate is facilitated. Is possible. Thus, the opening window and the movable plate formed on the pressure-receiving chamber side restraint plate are avoided by avoiding the displacement in the circumferential direction of the opening means formed on the pressure-receiving chamber side restraint plate and the pressure release means provided on the movable plate. It is possible to stably generate the fluid flow from the equilibrium chamber to the pressure receiving chamber, which is allowed by the cooperation of the depressurizing means provided in the chamber.

  In addition, the central part of the movable plate is a part that can be easily deformed by the action of hydraulic pressure in the movable plate. For example, the periphery of the notch formed in the movable plate is deformed. In the case where the depressurizing means is configured by the opening that is expressed in the movable plate, it is possible to easily express such opening, thereby stably fluid flow from the equilibrium chamber to the pressure receiving chamber. It becomes possible to produce.

  According to a third aspect of the present invention, in the fluid-filled vibration isolator according to the first or second aspect, the press-out means is configured by a through hole formed in the movable plate. Features.

  According to a fourth aspect of the present invention, in the fluid-filled vibration isolator according to the third aspect, the inner diameter of the through hole is 1 mm or less.

  According to a fifth aspect of the present invention, in the fluid-filled vibration isolator according to the third or fourth aspect, the balance chamber is formed on the pressure-receiving chamber side restraining plate and cooperates with the through hole. The inside diameter of the opening window that allows fluid flow from the pressure chamber to the pressure receiving chamber and the inside diameter of the through hole are substantially the same. In the fluid filled type vibration isolator having the structure according to this aspect, it is possible to make the opening area of the through hole and the opening area of the opening window substantially the same, thereby opening the opening area of the opening window. It is possible to avoid an increase in flow resistance and a corresponding decrease in the amount of fluid flow due to being made smaller than the opening area of the through hole, and as a result, from the equilibrium chamber through the through hole and the opening window. It is possible to secure a large amount of fluid that is allowed to flow into the pressure receiving chamber, and to quickly eliminate the excessive negative pressure that is generated in the pressure receiving chamber.

  According to a sixth aspect of the present invention, in the fluid-filled vibration isolator according to the first or second aspect, the movable plate is formed of a rubber material, and a cut is formed in the movable plate. The pressure release means is configured by an opening that is expressed in the movable plate by deforming the periphery of the cut in the movable plate due to a pressure difference between the pressure receiving chamber and the equilibrium chamber. To do.

  According to a seventh aspect of the present invention, in the fluid-filled vibration isolator according to the sixth aspect, the cut in the movable plate is formed in a cross shape. In such a fluid-filled vibration isolator having a structure according to this aspect, tongue-shaped press-moving movable pieces that are deformed so as to be swung up with respect to the movable plate are provided adjacent to each other in the circumferential direction. As a result, for example, a large opening is provided even in a small space, as compared to a case where a single tongue-like pressure-moving movable piece is provided on the movable plate by a notch formed in the movable plate. Can be rapidly expressed / disappeared.

  In addition, when one tongue piece-shaped pressure relief movable piece is provided on the movable plate by a cut formed in the movable plate, the periphery of the tongue piece-like pressure relief movable piece is fixed, When the tongue-shaped depressurized movable piece is deformed, that is, when the opening appears / disappears in the movable plate, there is a risk of malfunction due to friction. In the case of a cross-shaped incision that can be provided, each extruding movable piece will move simultaneously, thereby avoiding malfunction due to friction with its surroundings when deforming each extruding movable piece, It is possible to stabilize the deformation operation (opening / closing operation).

  According to an eighth aspect of the present invention, in the fluid-filled vibration isolator according to the seventh aspect, the length of each straight line portion in the cut is 2/3 or less of the outer dimension of the movable plate. This is a feature.

  According to a ninth aspect of the present invention, in the fluid-filled vibration isolator according to the seventh or eighth aspect, the movable body is formed by deforming a periphery of the notch formed on the pressure receiving chamber side restraint plate. By cooperating with the opening expressed in the plate, the length of each linear portion in the incision is made larger than the inner diameter dimension of the opening window allowing fluid flow from the equilibrium chamber to the pressure receiving chamber. It is characterized by being. In the fluid-filled vibration isolator having the structure according to this aspect, the deformation amount of the press-moving movable piece provided by forming a cross-shaped cut on the movable plate is changed to the peripheral portion of the opening window ( It is possible to limit by the outer part). As a result, it is possible to suppress the occurrence of cracks at the end of the cut, ensure the durability of the movable plate, and exhibit stable performance over a long period of time.

  According to a tenth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to ninth aspects, the second mounting member has a substantially cylindrical shape, and one of the second mounting members The first mounting member is spaced apart on the opening side of the first mounting member, and one opening of the second mounting member is formed by the main rubber elastic body connecting the first mounting member and the second mounting member. A fluid-tight cover and the other opening of the second mounting member are fluid-tightly covered with the flexible film, while a partition member supported by the second mounting member is used as the main rubber elastic body The pressure receiving chamber and the equilibrium chamber are formed on both sides of the partition member by disposing the second attachment member so as to extend in a direction perpendicular to the axis of the second attachment member between the opposing surfaces of the flexible membrane. A housing space extending in a direction perpendicular to the axis of the second mounting member inside the partition member. The movable plate is accommodated and disposed so as to spread in a direction perpendicular to the axis of the second mounting member with respect to the accommodation space, and the movable plate is disposed on the movable plate among the wall portions defining the accommodation space. On the other hand, the wall portion positioned on the pressure receiving chamber side constitutes the pressure receiving chamber side constraining plate, while the wall portion defining the accommodation space is positioned on the equilibrium chamber side with respect to the movable plate The equilibrium chamber side constraining plate is configured by a portion.

  In the fluid filled type vibration isolator having the structure according to this aspect, the pressure receiving chamber and the equilibrium chamber are efficiently formed on both sides of the partition member that forms the pressure receiving chamber side constraint plate and the equilibrium chamber side constraint plate. Thus, a fluid-filled vibration isolator that is compact as a whole can be realized. As a result, it can be used particularly advantageously as an engine mount for automobiles, for example.

  As is clear from the above description, in the fluid filled type vibration isolator having the structure according to the present invention, the movable plate is provided on the movable plate in a state in which the displacement to the pressure receiving chamber side is restricted by the pressure receiving chamber side restricting plate. The fluid flow from the equilibrium chamber to the pressure receiving chamber is allowed by the cooperation of the formed decompression means and the opening window formed in the pressure receiving chamber side restraining plate, while the movable plate is moved to the equilibrium chamber side by the balancing chamber side restraining plate. The fluid flow from the pressure receiving chamber to the equilibrium chamber through the decompression means provided on the movable plate in a state where the displacement to the fluid plate is constrained is prevented by the fluid flow blocking portion formed on the equilibrium chamber side restraint plate. Therefore, the fluid flow from the equilibrium chamber to the pressure receiving chamber can be positively allowed to quickly eliminate the excessive negative pressure generated in the pressure receiving chamber, and from the pressure receiving chamber to the equilibrium chamber. To prevent the fluid flow of the By raising, to ensure the flow amount of the fluid flowing through the orifice passage, it becomes possible to effectively exhibit the vibration damping effect based on flow action of resonance action etc. of the fluid flowing through the orifice passage.

  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 and FIG. 2 show an automobile engine mount 10 as a first 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. Further, under such a mounted state, the engine mount 10 is subjected to the shared support load of the power unit, and accordingly, the main rubber elastic body 16 is elastically deformed, and the first mounting bracket is attached. 12 and the second mounting member 14 are adapted to be relatively displaced by approaching a predetermined amount in the vertical direction in FIG. And the main vibration which should be vibrated is input into the substantially up-down direction in FIG. 1 between the 1st mounting bracket 12 and the 2nd mounting bracket 14. FIG.

  More specifically, the first mounting member 12 has a substantially disk shape, and a mounting bolt 18 protruding upward (upper side in FIG. 1) is fixedly provided at the center portion thereof. In addition, a holding fitting 20 is fixed to the lower surface of the first mounting fitting 12 on the central axis thereof. The holding metal fitting 20 is provided with a tapered peripheral wall portion that gradually expands toward the upper opening, and is fixed to the lower surface of the first mounting metal 12 at the opening edge.

  On the other hand, the second mounting bracket 14 has a large-diameter substantially cylindrical shape, and is below the first mounting bracket 12 on the substantially same central axis as the first mounting bracket 12 (lower side in FIG. 1). Are spaced apart. In addition, the second mounting bracket 14 has a structure in which a fitting tube portion 24 that protrudes downward in the axial direction from the outer peripheral edge portion of the substantially annular plate-shaped rubber fixing portion 22 is integrally formed. ing. The inner peripheral portion of the rubber adhering portion 22 has a tapered inclined shape that is gradually inclined downward in the axial direction toward the center.

  A main rubber elastic body 16 is disposed between the opposing surfaces of the first mounting bracket 12 and the second mounting bracket 14. The main rubber elastic body 16 has a large-diameter, generally frustoconical shape, and a large hollow recess 26 is formed at the center thereof. The circular recess 26 is a bottomed reverse circular hole that gradually expands in the downward direction and opens to the end surface on the large diameter side. By forming the circular recess 26, the main rubber elastic body 16 is a thick inverted cup shape as a whole.

  The first mounting bracket 12 is superposed on the end surface on the small diameter side on the upper side in the axial direction of the main rubber elastic body 16, and the holding bracket 20 and the first mounting bracket are welded and fixed to the lower surface of the first mounting bracket 12. A main rubber elastic body 16 is vulcanized and bonded to 12. In the present embodiment, the main rubber elastic body 16 is also filled in the holding metal fitting 20. Further, the rubber fixing portion 22 of the second mounting bracket 14 is inserted from the outer peripheral surface to the large-diameter side end portion of the main rubber elastic body 16 and vulcanized and bonded in a substantially embedded state. That is, in the present embodiment, 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.

  In addition, a substantially annular plate-shaped reinforcing metal fitting 28 is fixed to an axially intermediate portion of the main rubber elastic body 16 which is formed in a thick cylindrical shape, and the spring characteristics of the main rubber elastic body 16 are adjusted. Further, as shown in FIG. 1, the second mounting bracket 14 covers the entire lower surface of the rubber fixing portion 22 and the inner peripheral surface of the fitting tube portion 24 so as to cover the entire seal rubber layer 30. In this embodiment, the sealing rubber layer 30 is integrally formed with the main rubber elastic body 16.

  As described above, the integrally vulcanized molded product of the main rubber elastic body 16 including the first and second mounting brackets 12 and 14 has a partition member as a partition member from the axially lower opening of the second mounting bracket 14. A partition metal 32 and a diaphragm 34 as a flexible film are assembled.

  The partition fitting 32 has a thick, substantially disk shape. The diaphragm 34 is formed of a thin rubber elastic film that can be easily deformed, and the outer peripheral edge thereof is vulcanized and bonded to a substantially annular fitting 36. The partition fitting 32 and the diaphragm 34 are fitted and fixed to the second attachment fitting 14.

  Specifically, the partition metal fitting 32 is fitted into the fitting cylinder portion 24 provided on the second attachment metal fitting 14 so as to spread in the direction perpendicular to the axis of the second attachment metal fitting 14. The upper surface and the outer peripheral surface of the outer peripheral portion of the partition metal fitting 32 are fluid-tightly overlapped with the rubber fixing portion 22 and the fitting cylinder portion 24 of the second mounting metal member 14 via the seal rubber layer 30.

  The diaphragm 34 has a substantially disk shape that has a sufficient slack in the central portion and can be easily deformed. Further, the diaphragm 34 is vulcanized and bonded to the fitting 36 at the outer peripheral edge portion thereof. The fitting 36 has a structure in which a cylindrical fixed tube portion 40 protruding upward from the outer peripheral edge portion is integrally formed with an annular plate-shaped support portion 38. The outer peripheral edge of the diaphragm 34 is vulcanized and bonded to the inner peripheral edge. Moreover, the fixed cylinder part 40 in the fitting 36 is extrapolated to the fitting cylinder part 24 of the second mounting bracket 14 so as to be subjected to diameter reduction processing such as eight-way drawing. As a result, the support portion 38 of the fitting 35 is in contact with the lower surface of the outer peripheral portion of the partition fitting 32, and the fixed cylinder portion 40 of the fitting 35 is externally fixed to the fitting cylinder 24. . The space between the fitting surfaces of the fixed cylinder part 40 and the fitting cylinder part 24 is fluid-tightly sealed with a seal rubber layer 42 formed on the fixed cylinder part 40.

  As a result, the opening portion of the circular recess 26 formed in the main rubber elastic body 16 that is opened downward through the central hole of the second mounting bracket 14 is covered with the diaphragm 34 in a fluid-tight manner. An incompressible fluid is sealed in a region between the opposing surfaces of the main rubber elastic body 16 and the diaphragm 34 that is formed using the circular recess 26 and is sealed in an external space. An enclosed area is defined. For example, water, alkylene glycol, polyalkylene glycol, silicone oil or the like is employed as the incompressible fluid sealed in the fluid sealing region, and in particular, in order to effectively obtain a vibration isolation effect based on the fluid flow action. It is desirable to employ a low viscosity fluid of 0.1 Pa · s or less. The incompressible fluid is sealed by, for example, assembling the partition metal fitting 32 and the diaphragm 34 to the integrally vulcanized molded product of the main rubber elastic body 16 provided with the first and second attachment fittings 12 and 14. It is realized by performing in the inside.

  In addition, the fluid sealing region is divided into two in the vertical direction by the partition metal fitting 32 being disposed so as to extend 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 in the axial direction (the upper side in FIG. 1) sandwiching the partition member 32, and the first mounting member 12 and the second attachment member 12. A pressure receiving chamber 44 is formed in which pressure fluctuation is caused by elastic deformation of the main rubber elastic body 16 when vibration is input between the mounting brackets 14, while the other side in the axial direction sandwiching the partition bracket 32 is formed. On the lower side (in FIG. 1), a part of the wall portion is constituted by a diaphragm 34, and an equilibrium chamber 46 is formed in which volume change is easily allowed based on elastic deformation of the diaphragm 34.

  Further, as shown in FIG. 3 to FIG. 5, the partition metal fitting 32 is formed with a concave groove 48 that is open on the upper surface at the outer peripheral portion and extends continuously in the circumferential direction. The rubber fixing part 22 of the second mounting bracket 14 is covered fluid-tightly. As a result, a tunnel-shaped passage is present in the outer peripheral portion of the partition member 32. In the present embodiment, the concave groove 48 is formed by reciprocating in a circumferential direction at a portion of approximately 3/4 of the circumference of the partition metal 32, and the concave groove 48 is formed in the partition metal 32. In the portion of the circumference that does not extend over a substantially quarter circumference, a hollow portion is formed and is covered with a rubber adhering portion 22 in a fluid-tight manner like the concave groove 48.

  Further, one end portion of the concave groove 48 extends radially inward from the inner peripheral edge portion of the rubber fixing portion 22 of the second mounting bracket 14. A communication hole 50 is formed by opening an end of the groove 48 on the upper surface of the partition metal 32 on the circumferential side. Then, one end of the concave groove 48 is opened and connected to the pressure receiving chamber 44 through the communication hole 50. Further, the other end of the groove 48 is connected to the equilibrium chamber 46 through a communication hole 52 formed in the bottom wall portion of the groove 48 in the partition metal fitting 32. As a result, an orifice passage 54 is formed by using the concave groove 48 of the partition member 32, and the pressure receiving chamber 44 and the equilibrium chamber 46 are communicated with each other through the orifice passage 54. The orifice passage 54 is always maintained in a communication state in which the pressure receiving chamber 44 and the equilibrium chamber 46 are communicated.

  At the time of vibration input, relative pressure fluctuation is induced between the pressure receiving chamber 44 in which pressure fluctuation is caused and the equilibrium chamber 46 in which volume change is allowed based on the deformation of the diaphragm 34. Fluid flow through the orifice passage 54 occurs between the chambers 44 and 46. As a result, the anti-vibration effect based on the resonance action of the fluid that flows between the pressure receiving chamber 44 and the equilibrium chamber 46 through the orifice passage 54 is effective against vibration in the axial direction (vertical direction in FIG. 1) to be anti-vibrated. It has come to be demonstrated.

  In particular, in the present embodiment, the resonance frequency of the fluid that is allowed to flow through the orifice passage 54 exhibits an effective anti-vibration effect against low-frequency large-amplitude vibrations around 10 Hz such as a shake based on the resonance action of the fluid. Is tuned to be. The tuning of the resonance frequency is realized by changing the setting of the passage cross-sectional area and the passage length of the orifice passage 54, for example.

  Further, a circular central concave portion 56 that opens upward is formed in the central portion of the partition fitting 32. In the present embodiment, the central recess 56 has a substantially constant depth throughout. In addition, a disc-shaped cover plate fitting 58 as shown in FIG. 6 is superimposed on the center portion of the partition fitting 32 so as to be aligned with the three positioning protrusions provided on the partition fitting 32. The positioning protrusions are caulked to be fixed to the partition metal fitting 32 with the central recess 56 covered. As a result, a hollow housing space 60 having a predetermined inner diameter and height and extending in a disk shape is formed inside the partition member 32. In particular, in the present embodiment, the central recess 56 constituting the accommodation space 60 is formed in the central portion of the partition fitting 32, and the partition fitting 32 is positioned on the same central axis as the second attachment fitting 14. Therefore, the accommodation space 60 is formed on the central axis of the second mounting bracket 14. And in this accommodation space 60, the movable rubber plate 62 as a movable plate is accommodated and arrange | positioned.

  As shown in FIG. 7, the movable rubber plate 62 has a disk shape as a whole, and is formed of a rubber material in this embodiment. Further, on both the upper and lower surfaces of the movable rubber plate 62, an annular inner buffer lip protrusion 64 extending continuously in the circumferential direction in the radial direction and an annular shape extending continuously in the circumferential direction at the outer peripheral edge portion, respectively. The outer buffer lip protrusion 66 is integrally formed to protrude. In the present embodiment, the inner buffer lip protrusion 64 and the outer buffer lip protrusion 66 have the same protrusion height.

  Further, the movable rubber plate 62 has a maximum thickness dimension (thickness dimension of a portion where the inner buffer lip protrusion 64 or the outer buffer lip protrusion 66 is integrally formed) smaller than the height dimension of the accommodation space 60. Yes. As a result, under the state where the movable rubber plate 62 is positioned at the center in the accommodation space 60, a gap is formed around the whole movable rubber plate 62 between the inner surface of the accommodation space 60. It has become so. The movable rubber plate 62 is allowed to be freely displaced in the accommodation space 60 by a stroke corresponding to the size of the gap.

  Furthermore, in the present embodiment, a slit 68 as a cut is formed in a cross shape in the central portion of the movable rubber plate 62. As a result, four tongue-shaped depressurizing movable pieces 70 are provided in the central portion of the movable rubber plate 62 so as to be adjacent in the circumferential direction. In particular, in the present embodiment, the outer end portion of the cross-shaped slit 68 is positioned near the inner edge of the inner buffer lip protrusion 64. Therefore, in this embodiment, the four pressure-removable movable pieces 70 are provided in a portion of the movable rubber plate 62 inside the inner buffer lip protrusion 64.

  In addition, the lid plate metal 58 constituting the upper and lower wall parts of the housing space 60 and the bottom wall 72 of the central recess 56 in the partition metal fitting 32 are annular contact parts extending continuously in the circumferential direction in the radial direction. 74, 76 are provided. In particular, in the present embodiment, the inner side in the radial direction of the annular contact portion 74 of the lid plate metal 58 is a single circular central communication hole 78 as a whole. Here, the inner diameter of the central communication hole 78 is made smaller than the length of each straight line portion in the cross-shaped slit 68.

  On the other hand, an inner contact portion 80 having a communication hole is formed on the bottom wall 72 of the central recess 56 in the partition member 32 on the radially inner side of the annular contact portion 76. In particular, in the present embodiment, the inner contact portion 80 has a cross shape extending in the radial direction perpendicular to each other. The inner contact portion 80 defines the inner side in the radial direction of the annular contact portion 76, so that four inner communication holes 82 are formed on the inner side in the radial direction of the annular contact portion 76.

  Furthermore, a plurality of communication holes are formed on the periphery of the lid plate metal 58 and the bottom wall 72 of the central recess 56 in the partition metal 32 on the outer periphery in the radial direction of the annular contact portions 74 and 76. Has been. In particular, in the present embodiment, the outer contact portions 84 and 86 extending in eight radial directions are radially outward of the annular contact portions 74 and 76 with respect to both the lid plate metal 58 and the bottom wall 72. Thus, the radially outer sides of the annular contact portions 74 and 76 are partitioned, and eight outer communication holes 88 and 90 are formed radially outward of the annular contact portions 74 and 76. Has been.

  The upper surface of the movable rubber plate 62 accommodated in the accommodating space 60 is exposed to the pressure receiving chamber 44 through the central communicating hole 78 and the outer communicating hole 88 formed in the lid plate metal 58 in this way. On the other hand, the lower surface of the movable rubber plate 62 is exposed to the equilibrium chamber 46 side through the inner communication hole 82 and the outer communication hole 90 formed in the bottom wall 72 of the central recess 56.

  Therefore, the internal pressure of the pressure receiving chamber 44 and the equilibrium chamber 46 is exerted on the movable rubber plate 62 on the upper surface and the lower surface, and the movable rubber plate is based on the pressure difference between the pressure receiving chamber 44 and the equilibrium chamber 46 when vibration is input. A displacement in the plate thickness direction (axial direction) is caused with respect to 62. Then, based on the displacement of the movable rubber plate 62 in the axial direction, the fluid flow through the communication holes 78, 82, 88, 90 of the cover plate fitting 58 and the partition fitting 32 is generated. The hydraulic pressure absorbing action based on releasing the pressure fluctuation of the pressure receiving chamber 44 to the equilibrium chamber 46 is exhibited, and a low dynamic spring effect with respect to the input vibration is exhibited.

  Note that the allowable stroke in the vertical direction (plate thickness direction) of the movable rubber plate 62 in the accommodation space 60 is the amplitude of the input vibration to be damped, the effective piston diameter in the pressure receiving chamber 44 of the engine mount 10, the movable rubber. It is appropriately adjusted depending on the size of the plate 62 and the like. In this embodiment, when an amplitude vibration of ± 0.5 to 2.0 mm corresponding to an engine shake is applied between the first mounting bracket 12 and the second mounting bracket 14, the movable rubber plate 62 is moved. In the region where the movable rubber plate 62 does not abut against the inner surface of the accommodation space 60 when the medium or small amplitude vibration of ± 0.25 mm or less corresponding to idling vibration or traveling noise is input. The size of the gap between the opposed surfaces of the upper and lower surfaces of the movable rubber plate 62 and the inner surface of the accommodation space 60 is set so that the displacement is allowed.

  Therefore, in this embodiment, a shocking large load vibration is input between the first mounting bracket 12 and the second mounting bracket 14, and the first mounting bracket 12 is separated from the second mounting bracket 14. When displaced in the direction to be squeezed, an excessive negative pressure generated in the pressure receiving chamber 44 acts, whereby the movable rubber plate 62 is displaced to the pressure receiving chamber 44 side.

  At this time, first, as shown in FIG. 8, the inner buffer lip protrusion 64 is brought into contact with the annular contact portion 74 of the lid plate metal 58 and the outer buffer lip projection 66 is brought into contact with the lid plate metal 58. It is made to contact | abut to an outer peripheral part (part located in radial direction outer side rather than the outer side communication hole 88). Subsequently, as shown in FIG. 9, the inner buffer lip protrusion 64 and the outer buffer lip protrusion 66 are crushed and the movable rubber plate 62 is brought into close contact with the lid plate metal fitting 58, thereby The central communication hole 78 and the outer communication hole 88 formed in the lid plate metal 58 are closed. Therefore, in this embodiment, in a state where the movable rubber plate 62 is closely attached to the lid plate metal 58 as described above, the intersecting portion in the slit 68 formed in the movable rubber plate 62 is below the central communication hole 78. It is designed to be positioned in

  As shown in FIGS. 10 and 11, the periphery of the cross-shaped slit 68 is deformed, so that the movable rubber plate 62 is formed below the central communication hole 78 formed in the cover plate metal fitting 58. The opening 92 can be expressed. That is, in the present embodiment, the four pressure-removable movable pieces 70 are deformed so as to be rolled toward the pressure receiving chamber 44, and a part of the pressure-moving movable pieces 70 enters the central communication hole 78, thereby moving the movable rubber plate 62. The opening 92 developed in FIG. 5 is positioned below the central communication hole 78. As a result, fluid flow from the equilibrium chamber 46 to the pressure receiving chamber 44 through the opening 92 and the central communication hole 78 is allowed.

  As is clear from this, in the present embodiment, the lid plate metal 58 constitutes the pressure receiving chamber side restraint plate. Further, in the present embodiment, the depressurizing means is constituted by the opening 92 that is expressed in the movable rubber plate 62. Furthermore, in this embodiment, each of the central communication hole 78 and the outer communication hole 88 forms an opening window (an opening window formed in the pressure receiving chamber side restraining plate). In cooperation with the means, an opening window that allows fluid flow from the equilibrium chamber 46 to the pressure receiving chamber 44 is formed.

  Further, in the state where the opening 92 is expressed in the movable rubber plate 62 in this way, the inner buffer lip protrusion 64 in the movable rubber plate 62, that is, a portion positioned just outside the outer end portion of the slit 68. In addition, since the abutting portion 74 is brought into contact with the annular contact portion 74 of the lid plate metal fitting 58, the deformation of each press-release movable piece 70 is constrained over the entire circumferential direction. Therefore, excessive deformation in the press-moving movable piece 70 is prevented by efficiently distributing stress in the circumferential direction. Thereby, the crack etc. of the part in which the slit 68 is formed in the movable rubber plate 62 are prevented, and the durability and reliability of the movable rubber plate 62 are improved. As described above, when the slit 68 (cut) extending in the radial direction is employed, the outer end of the slit 68 (cut) is preferably at least inside the outer edge of the annular contact portion 74. Thereby, it is possible to advantageously prevent the occurrence of cracks while ensuring a sufficient amount of deformation around the slit 68 (cut).

  On the other hand, when vibration is input between the first mounting bracket 12 and the second mounting bracket 14 and the first mounting bracket 12 and the second mounting bracket 14 are displaced close to each other, the pressure receiving chamber 44. Is increased to a positive pressure, and the movable rubber plate 62 is displaced toward the equilibrium chamber 46 by the action of the positive pressure. Then, as shown in FIG. 12, the movable rubber plate 62 is first brought into contact with the bottom wall 72 of the central recess 56 in the partition metal fitting 32 at the inner buffer lip protrusion 64 and the outer buffer lip protrusion 66. It has become. Accordingly, in the present embodiment, the inner buffer lip protrusion 64 is brought into contact with the annular contact portion 76, and the outer buffer lip protrusion 66 is positioned radially outward from the outer communication hole 90. The outer peripheral edge of the bottom wall 72 is brought into contact with the outer peripheral edge.

  From this state, the inner buffer lip protrusion 64 and the outer buffer lip protrusion 66 are crushed, and as shown in FIG. 13, the movable rubber plate 62 against the bottom wall 72 of the central recess 56 in the partition metal 32. Is brought into close contact. As a result, the inner communication hole 82 and the outer communication hole 90 formed in the bottom wall 72 of the central recess 56 in the partition member 32 are closed by the movable rubber plate 62.

  Therefore, in this embodiment, as shown in FIG. 14, the intersecting portion in the slit 68 formed in the movable rubber plate 62, that is, the tip portion that is first deformed in the pressure-removable movable piece 70, The inner abutment portion 80 is brought into contact with the central intersecting portion, whereby the deformation of the press-moving movable piece 70, that is, the expression of the opening 92 is stably prevented. Yes. Further, in this embodiment, even if the movable rubber plate 62 is displaced in the direction perpendicular to the axis or rotated in the circumferential direction, as described above, the intersecting portion in the slit 68 formed in the movable rubber plate 62. Is set to have a gap dimension between the side surface of the movable rubber plate 62 and the inner surface of the accommodation space 60 that is opposed to the side surface so that the inner abutment portion 80 abuts against the central intersection. .

  As is clear from the above description, in this embodiment, the equilibrium chamber side restraint plate is configured by the bottom wall 72 of the central recess 56 in the partition member 32. In the present embodiment, each of the inner communication hole 82 and the outer communication hole 90 forms an opening window (an opening window formed in the equilibrium chamber side restraining plate). Furthermore, in this embodiment, the fluid flow blocking portion is configured by the inner abutment portion 80 that prevents the deformation of the press-release movable piece 70, that is, the expression of the opening 92.

  Therefore, in the engine mount 10 of the present embodiment, when vibration is input and the first mounting bracket 12 and the second mounting bracket 14 are brought close to each other, the pressure in the pressure receiving chamber 44 is sufficiently increased so that the orifice It is possible to secure a sufficient amount of fluid that can flow through the passage 54, thereby suppressing a decrease in loss factor and advantageously preventing a decrease in vibration-proof characteristics against shake vibration. On the other hand, when a shocking heavy load vibration is input and an excessive negative pressure is generated in the pressure receiving chamber 44, the opening 92 and the lid plate metal 58 formed in the movable rubber plate 62 are formed. Fluid flow from the equilibrium chamber 46 to the pressure receiving chamber 44 through the central communication hole 78 is allowed, and generation of abnormal noise due to cavitation can be reduced or prevented.

  Further, in the present embodiment, when the negative pressure generated in the pressure receiving chamber 44 is applied, the four movable extruding pieces 70 are deformed so that they are simultaneously beaten. It is possible to avoid a malfunction due to friction with the surroundings when it is done, thereby stabilizing the expression of the opening 92.

  Furthermore, in this embodiment, since the length of each straight line portion in the slit 68 is larger than the inner diameter dimension of the central communication hole 78, the length of each straight line portion in the slit 68 and the inner diameter of the central communication hole 78. By appropriately setting the size, the periphery of the slit 68 can be deformed at any position within the allowable movable range in the direction perpendicular to the axis of the movable rubber plate 62, that is, four depressing movable pieces. The opening 92 that appears when the 70 is deformed is stably positioned below the central communication hole 78 (an opening window that allows fluid flow from the equilibrium chamber to the pressure receiving chamber by cooperating with the pressure-removing means). Accordingly, fluid flow from the equilibrium chamber 46 to the pressure receiving chamber 44 through the opening 92 and the central communication hole 78 can be stably generated.

  Incidentally, it was confirmed that no abnormal noise due to cavitation occurred when the sensitivity evaluation for abnormal noise due to cavitation was performed using the engine mount 10 of the present embodiment.

  FIG. 15 shows an engine mount 94 as a second embodiment of the present invention. In the following description, members and parts having the same structure as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed descriptions thereof are omitted. To do.

  The engine mount 94 of the present embodiment is different in the shape of the movable rubber plate 96 from the engine mount (10) of the first embodiment.

  More specifically, as shown in FIG. 16, the movable rubber plate 96 employed in the engine mount 94 of the present embodiment has a pressure as a through hole penetrating in the thickness direction at the center portion. A hole 100 is formed, and the whole has a circular plate shape. The inner diameter dimension of the press-out hole 100 is set to 1 mm or less. In particular, in this embodiment, the inner diameter dimension of the central communication hole 78 formed in the lid plate metal 58 is smaller. The movable rubber plate 96 includes an inner buffer lip projection (64) and an outer buffer lip projection (66), like the movable rubber plate (62) employed in the engine mount (10) of the first embodiment. Is not formed, so that the upper surface and the lower surface of the movable rubber plate 96 are both flat surfaces.

  In the engine mount 94 having such a structure, a shocking large load vibration is input between the first mounting bracket 12 and the second mounting bracket 14, and the first mounting bracket 12 is moved to the second mounting bracket 12. If the mounting bracket 14 is displaced away from the mounting bracket 14, an excessive negative pressure is generated in the pressure receiving chamber 44, and the movable rubber plate 96 is displaced toward the pressure receiving chamber 44 due to the negative pressure acting. As a result, the movable rubber plate 96 is brought into close contact with the lid plate fitting 58 as shown in FIG. At this time, the outer communication hole 88 formed in the lid plate metal 58 is closed by the movable rubber plate 96, but the central communication hole 78 is not closed by the press-off hole 100 formed in the movable rubber plate 96. Thus, the accommodation space 60 is communicated with the pressure receiving chamber 44 through the pressure release hole 100 formed in the movable rubber plate 96 and the central communication hole 78 formed in the cover plate metal fitting 58. As a result, fluid flow from the equilibrium chamber 46 to the pressure receiving chamber 44 is allowed through the pressure release hole 100 formed in the movable rubber plate 96 and the central communication hole 78 formed in the lid plate metal 58. As is clear from this, in the present embodiment, the pressure relief means is constituted by the pressure relief hole 100.

  On the other hand, when vibration is input between the first mounting bracket 12 and the second mounting bracket 14 and the first mounting bracket 12 is displaced in a direction approaching the second mounting bracket 14, The pressure in the pressure receiving chamber 44 is increased, whereby the movable rubber plate 96 is displaced toward the equilibrium chamber 46 side. As shown in FIG. 18, when the movable rubber plate 96 is brought into close contact with the bottom wall 72 of the central recess 56, the inner communication hole 82 and the outer communication hole 90 formed in the bottom wall 72 of the central recess 56. Is closed by a movable rubber plate 96. Further, as shown in FIG. 19, the pressure release hole 100 formed in the movable rubber plate 96 is closed by the central intersecting portion of the inner contact portion 80 provided in the bottom wall 98 of the central recess 56. It is like that. Thereby, the fluid flow from the pressure receiving chamber 44 to the equilibrium chamber 46 through the accommodation space 60 is prevented, and the pressure in the pressure receiving chamber 44 can be sufficiently increased. As is clear from this, in the present embodiment, the fluid flow blocking portion is configured by the inner contact portion 80 that closes the pressure release hole 100.

  Therefore, in the present embodiment, the entire punching hole 100 is opposed to the central intersection portion of the inner contact portion 80 in the axial direction at any position within the allowable movable range in the direction perpendicular to the axis of the movable rubber plate 96. The size of the press-out hole 100 and the size of the central intersecting portion of the inner contact portion 80 are set so that the movable rubber plate 96 is in close contact with the bottom wall 72 of the central concave portion 56. Below, the closed state by the inner contact part 80 of the pressure release hole 100 is stably generated.

  Therefore, the engine mount 94 of this embodiment can also obtain the same effect as the engine mount (10) of the first embodiment.

  Further, in the present embodiment, the inner diameter dimension of the pressure relief hole 100 is smaller than the inner diameter dimension of the central communication hole 78, that is, the opening window that allows fluid flow from the equilibrium chamber to the pressure receiving chamber in cooperation with the decompression means. Therefore, by appropriately setting the size of the inner diameter of the press-out hole 100 and the size of the inner diameter of the central communication hole 78, any position within the allowable range in the direction perpendicular to the axis of the movable rubber plate 96 is set. In this case, the entire pressure release hole 100 can be opened to the pressure receiving chamber 44 through the central communication hole 78, whereby the equilibrium chamber 46 through the pressure release hole 100 and the central communication hole 78 can be changed to the pressure receiving chamber 44. It is possible to produce a stable fluid flow.

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

  For example, in the first embodiment, the slit 68 (cut) is formed in a cross shape and the four tongue-like depressing movable pieces 70 are formed, but one tongue-like depressing movable portion is formed. A notch that forms a piece may be formed in the movable plate.

  Further, the cut formed in the movable plate is not limited to a cross shape as in the first embodiment, and for example, an H shape, an I shape (one straight line shape), a U shape, a V shape, A character shape, a Y shape, or the like can be employed. Furthermore, the number of cuts formed in the movable plate is not limited to one as in the first embodiment, and may be plural. Specifically, for example, a plurality of I-shaped (single straight) cuts or U-shaped cuts may be formed on the movable plate.

  In the first embodiment, the slit 68 (cut) is formed to be parallel to the axial direction of the movable rubber plate 62 (movable plate), but is inclined with respect to the axial direction of the movable plate. A cut may be formed in the direction.

  Furthermore, the number of communication holes formed in the cover plate metal 58 and the number and formation positions of the communication holes formed in the bottom wall 72 of the central recess 56 are the same as those described in the first and second embodiments. Without being limited thereto, for example, in the second embodiment, the inner communication hole 82 may not be formed in the bottom wall 72 of the central recess 56.

  In the first and second embodiments, specific examples of applying the present invention to the fluid-filled vibration isolator having one orifice passage are shown, but a plurality of orifice passages are provided. Of course, the present invention can be applied to the fluid-filled vibration isolator.

  Furthermore, the tuning frequency of the orifice passage is not limited to those of the first and second embodiments.

  Further, the shape of the movable plate is not limited to the shapes of the first and second embodiments. For example, the central portion is a circular flat plate portion and the outer peripheral portion extends over the entire circumference. For example, it may be a ring-shaped plate that is undulated in the circumferential direction, or at least a portion that is a wavy portion that spreads in a substantially corrugated shape with continuous irregularities.

  Furthermore, in the first embodiment, the inner buffer lip protrusion 64 and the outer buffer lip protrusion 66 are integrally formed with the movable rubber plate 62. However, the inner buffer lip protrusion 64 and the outer buffer lip protrusion 66 are movable. The rubber plate 62 may not be formed.

  In the first embodiment, the length of each linear portion in the slit 68 is set to be larger than the inner diameter dimension of the central communication hole 78, but may be smaller than the inner diameter dimension of the central communication hole 78. good.

  Further, the shape of the fluid flow blocking portion is not limited to those of the first and second embodiments, and may be, for example, a disk shape.

  Furthermore, in the second embodiment, the inner diameter of the press-out hole 100 is the center communication hole 78, that is, an opening window that allows fluid flow from the equilibrium chamber to the pressure-receiving chamber by cooperating with the press-out means. Although the inner diameter dimension is smaller than the inner diameter dimension, the inner diameter dimension of the press-out hole 100 and the inner diameter dimension of the central communication hole 78 may be substantially the same.

  Furthermore, in the first and second embodiments, the second mounting member has a substantially cylindrical shape, and the first mounting member is spaced apart from one opening side of the second mounting member. Although the specific example of what applied this invention was shown with respect to the fluid enclosure type vibration isolator of the structure where the 1st attachment member was made into the rod shape, the 2nd attachment member was cylindrical shape The present invention can also be applied to a fluid-filled vibration isolator having a structure in which the first mounting member is inserted and arranged in the second mounting member.

  In addition, in the first and second embodiments, specific examples of applying the present invention to an engine mount for automobiles have been shown. However, the present invention is not limited to automobile body mounts or other than automobiles. Any of the anti-vibration devices used in these various devices is advantageously applied.

  In addition, although not enumerated one by one, the present invention can be carried out in a mode to which various changes, modifications, improvements and the like are added based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the present invention.

1 is a longitudinal sectional view showing an automobile engine mount as a first embodiment of the present invention. It is a top view of the engine mount shown by FIG. It is a top view which shows the partition metal fitting which comprises the engine mount shown by FIG. It is IV-IV sectional drawing in FIG. It is a bottom view of the partition metal fitting shown by FIG. It is a top view which shows the cover metal fitting which comprises the engine mount shown by FIG. It is a top view which shows the movable rubber plate which comprises the engine mount shown by FIG. It is an expanded sectional view for demonstrating the state by which the movable rubber plate was made to contact | abut with a lid plate metal fitting. It is an expanded sectional view for demonstrating the state by which the movable rubber plate was closely_contact | adhered to the lid metal fitting. It is an expanded sectional view for demonstrating the state by which opening was made to express in a movable rubber board. It is a top view for demonstrating the state by which opening was made to express in a movable rubber board. It is an expanded sectional view for demonstrating the state by which the movable rubber plate was made to contact | abut to the bottom wall of a center recessed part. It is an expanded sectional view for demonstrating the state by which the movable rubber plate was stuck to the bottom wall of the center recessed part. It is a top view for demonstrating the state by which the movable rubber plate was closely_contact | adhered to the bottom wall of the center recessed part, Comprising: It is a top view which shows the state from which the cover plate metal fitting was removed. It is a longitudinal cross-sectional view which shows the engine mount as 2nd embodiment of this invention. It is a top view which shows the movable rubber plate employ | adopted as the engine mount shown by FIG. It is an expanded sectional view for demonstrating the state by which the movable rubber plate was closely_contact | adhered to the lid metal fitting. It is an expanded sectional view for demonstrating the state by which the movable rubber plate was stuck to the bottom wall of the center recessed part. It is a top view for demonstrating the state by which the movable rubber plate was closely_contact | adhered to the bottom wall of the center recessed part, Comprising: It is a top view which shows the state from which the cover plate metal fitting was removed.

Explanation of symbols

10 Engine mount 12 First mounting bracket 14 Second mounting bracket 16 Main rubber elastic body 34 Diaphragm 44 Pressure receiving chamber 46 Equilibrium chamber 54 Orifice passage 58 Cover plate bracket 62 Movable rubber plate 72 Bottom wall 78 Central communication hole 80 Inside contact Portion 82 Inner communication hole 88 Outer communication hole 90 Outer communication hole 92 Opening

Claims (10)

A pressure receiving chamber in which a first mounting member and a second mounting member are connected by a main rubber elastic body, a part of the wall portion is configured by the main rubber elastic body, and pressure fluctuations are generated at the time of vibration input; and a wall portion Are formed of a flexible membrane to form an equilibrium chamber in which volume change is allowed, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber are mutually connected. The movable plate that divides the pressure receiving chamber and the equilibrium chamber is disposed so as to be minutely displaceable in the plate thickness direction, and the pressure receiving chamber that is exerted on one surface of the movable plate and the In a fluid-filled vibration isolating apparatus in which minute pressure fluctuations in the pressure receiving chamber at the time of vibration input are released to the equilibrium chamber and absorbed based on displacement in the thickness direction of the movable plate based on the pressure difference in the equilibrium chamber ,
A pressure receiving chamber side restraining plate for restraining displacement of the movable plate toward the pressure receiving chamber side, and an equilibrium chamber side restraining plate for restraining displacement of the movable plate toward the equilibrium chamber side, and these pressure receiving chamber side restraining plates. And the equilibrium chamber side restraint plate, respectively, and the pressure receiving chamber in a state where the displacement of the movable plate to the pressure receiving chamber side is restrained by the pressure receiving chamber side restraining plate with respect to the movable plate. There is provided pressure-removing means for allowing fluid flow from the equilibrium chamber to the pressure receiving chamber by cooperating with the opening window formed in the side restraint plate, and the movable plate with respect to the equilibrium chamber side restraint plate. Is provided with a fluid flow blocking portion for blocking fluid flow from the pressure receiving chamber to the equilibrium chamber through the pressure release means in a state where displacement to the equilibrium chamber side is constrained by the equilibrium chamber side restraining plate. A fluid-filled vibration damping device.   The fluid filled type vibration damping device according to claim 1, wherein the depressurizing means is provided in a central portion of the movable plate.   The fluid-filled vibration isolator according to claim 1 or 2, wherein the depressurizing means is constituted by a through hole formed in the movable plate.   The fluid-filled vibration isolator according to claim 3, wherein an inner diameter of the through hole is 1 mm or less.   An inner diameter dimension of the opening window that is formed in the pressure receiving chamber side restraining plate and allows fluid flow from the equilibrium chamber to the pressure receiving chamber by cooperating with the through hole, and an inner diameter dimension of the through hole are substantially equal. The fluid-filled vibration isolator according to claim 3 or 4, which is the same.   The movable plate is formed of a rubber material, and a cut is formed in the movable plate, and the periphery of the cut in the movable plate is deformed by a pressure difference between the pressure receiving chamber and the equilibrium chamber. The fluid-filled vibration isolator according to claim 1 or 2, wherein the press-out means is configured by an opening that is expressed in the movable plate.   The fluid filled type vibration damping device according to claim 6, wherein the cut in the movable plate is formed in a cross shape.   The fluid-filled vibration isolator according to claim 7, wherein the length of each linear portion in the cut is 2/3 or less of the outer dimension of the movable plate.   A fluid flow from the equilibrium chamber to the pressure receiving chamber is allowed by cooperating with the opening formed in the pressure receiving chamber side restraining plate and deformed around the notch to be expressed in the movable plate. The fluid-filled vibration isolator according to claim 7 or 8, wherein a length of each linear portion in the cut is larger than an inner diameter dimension of the opening window.   The second mounting member has a substantially cylindrical shape, and the first mounting member and the second mounting member are separated from each other on one opening side of the second mounting member. The main rubber elastic body to be coupled covers one opening of the second mounting member fluid-tightly, and the other opening of the second mounting member is fluid-tightly covered by the flexible film. On the other hand, by disposing the partition member supported by the second mounting member so as to spread in the direction perpendicular to the axis of the second mounting member between the opposing surfaces of the main rubber elastic body and the flexible membrane. The pressure receiving chamber and the equilibrium chamber are formed on both sides of the partition member, and an accommodation space is formed in the partition member so as to extend in a direction perpendicular to the axis of the second mounting member. The second mounting member extends in a direction perpendicular to the axis of the second mounting member with respect to the space. The pressure plate chamber-side restraint plate is configured by a wall portion that is disposed to accommodate the moving plate and is positioned on the pressure chamber side with respect to the movable plate among the wall portions that define the storage space. The fluid-filled vibration isolator according to any one of claims 1 to 9, wherein the equilibrium chamber side restraining plate is configured by a wall portion positioned on the equilibrium chamber side with respect to the movable plate among the defining wall portions. .

Images