JP2010249287A - Vibration control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration control device suppressing abnormal noise when a movement opening/closing member is moved to a closed position. <P>SOLUTION: An orifice opening 74 formed in a partition fitting 36 of the vibration control device 10 is opened and closed by movement of the movement opening/closing member 78. A shock absorbing rubber ring 142 is attached to a lower end 78L of the movement opening/closing member 78, and the lower end 78L of the shock absorbing rubber ring 142 does not directly abut on a contacted surface 76T of a cylinder member 76 when the movement opening/closing member 78 is moved to the closed position, and therefore, abnormal noise is suppressed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fluid-filled vibration isolator that prevents transmission of vibration from a member that generates vibration, and more particularly, to a vibration isolator that is suitably used for an engine mount of an automobile.

  For example, in a vehicle such as a passenger car, a vibration isolator as an engine mount is disposed between an engine serving as a vibration generating unit and a vehicle body serving as a vibration receiving unit, and the vibration isolating device generates vibration generated from the engine. It is structured to absorb and prevent transmission to the vehicle body side.

  As a vibration isolator having such a structure, Patent Document 1 discloses that a main liquid chamber and a sub liquid chamber are communicated with each other by a shake orifice and an idle orifice, forming a part of the idle orifice and communicating with the sub liquid chamber. The plunger member arranged in the cylinder space is moved to the closed position where the idle orifice is closed by the hydraulic pressure of the main fluid chamber when the shake vibration is input, and the idle force is received by the biasing force of the coil spring when the idle vibration is input. A vibration isolator that moves to an open position that opens the orifice is disclosed.

  In the vibration isolator described in Patent Document 1, when the plunger member (moving opening / closing member) moves to the closed position, there is a possibility that it will hit the cylinder chamber and generate an abnormal noise. .

JP 2007-71313 A

  In view of the above facts, an object of the present invention is to obtain a vibration isolator capable of suppressing the generation of abnormal noise when the moving opening / closing member moves.

  In the first aspect of the present invention, the first mounting member connected to one of the vibration generating portion and the vibration receiving portion, the second mounting member connected to the other of the vibration generating portion and the vibration receiving portion, and the first An elastic body disposed between the mounting member and the second mounting member, and a main liquid chamber in which liquid is sealed with the elastic body as a part of a partition, and the internal volume changes with elastic deformation of the elastic body A sub liquid chamber in which a liquid is enclosed and whose internal volume can be expanded, a plurality of passages communicating the main liquid chamber and the sub liquid chamber with each other, and between the main liquid chamber and the sub liquid chamber A cylinder member that constitutes a cylinder chamber filled with liquid, a check valve that allows movement of the liquid from the main liquid chamber only in the direction of the cylinder chamber, and a part of the cylinder chamber and the passage An orifice opening provided in the cylinder member so as to communicate with the main liquid; A moving opening / closing member that opens and closes the orifice opening by moving in the cylinder chamber in accordance with a fluid pressure fluctuation to select the passage and switches between a shake mode and an idle mode, and the moving opening / closing member includes the cylinder An urging member that elastically supports the reciprocating movement in the room, a buffer member that is provided on the moving opening and closing member and cushions by contacting a contacted portion of the cylinder member that is located on the distal side in the moving direction of the moving opening and closing member; Have

  In the vibration isolator of claim 1, when vibration is transmitted to one of the first mounting member and the second mounting member, the elastic body disposed between the first mounting member and the second mounting member is elastic. The vibration is absorbed by the vibration absorbing action based on the internal friction or the like of the elastic body, and the vibration transmitted to the vibration receiving portion side is reduced.

  Moreover, in the vibration isolator which concerns on Claim 1, the main liquid chamber and the subliquid chamber are connected by the some flow path.

  Further, in this vibration isolator, when the fluid pressure fluctuation of the main fluid chamber is caused by the liquid flowing into the cylinder chamber through the check valve with respect to the moving opening / closing member, the biasing force is resisted against the biasing force of the biasing member or In response to this, the moving opening / closing member moves in the cylinder chamber, whereby the orifice opening is opened and closed, and switching between the shake mode and the idle mode is performed.

  For example, when vibration with relatively low frequency and large amplitude (hereinafter referred to as “low frequency range vibration”) is input, the vibration isolator can be set to a so-called shake mode.

  Further, in this vibration isolator, when vibration with relatively high frequency and small amplitude (hereinafter referred to as “high frequency region vibration”) is input, the vibration isolator can be set to a so-called idle mode. .

  Further, in this vibration isolator, a buffer member is provided on the moving opening / closing member, and when the moving opening / closing member moves, the buffer member exerts a buffering action by contacting the contacted portion of the cylinder member. Therefore, it is possible to suppress the generation of abnormal noise as compared with a configuration in which such a buffer member is not provided.

  A second aspect of the present invention is the first aspect of the present invention, wherein the shock-absorbing member is provided with a convex portion that protrudes toward the contacted portion.

  Therefore, by the movement of the movable opening / closing member to the closed position, first, the tip of the convex portion comes into contact with the contacted portion of the cylinder member. When the movable opening / closing member further moves, the tip of the convex portion is deformed, and the buffer member comes into contact with the contacted portion of the cylinder member with a wider contact area. Thereby, since the stroke when a buffer member contacts the to-be-contacted part of a cylinder chamber becomes long, the buffer effect becomes higher. In addition, the effect of suppressing inadvertent liquid movement between the buffer member and the contacted portion of the cylinder chamber (leak suppression effect) is also increased.

  According to a third aspect of the present invention, in the second aspect of the present invention, a plurality of the convex portions are provided.

  By providing a plurality of convex portions as described above, the buffering effect and the leak suppressing effect are further enhanced as compared with the configuration in which only one convex portion is provided.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the end surface of the movable opening / closing member on which the buffer member is attached constitutes one end of the movable opening / closing member. And an inner surface portion continuous from the end surface portion, and the buffer member has a first contact surface that contacts the end surface portion and a second contact surface that contacts the inner surface portion.

  Therefore, the buffer member contacts the end surface portion of the movable opening / closing member at the first contact surface, and contacts the inner surface portion of the movable opening / closing member at the second contact surface. Thus, a higher leak suppression effect is obtained by attaching the buffer member in contact with the movable opening / closing member on two different surfaces.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the buffer member is made of rubber, and the movable opening and closing member is made of resin.

  Thus, by making the buffer member made of rubber and the movable opening / closing member made of resin, the buffer member can be integrally formed with the moving opening / closing member by heat welding or the like, which contributes to improvement in productivity.

  According to a sixth aspect of the present invention, in the first aspect of the present invention, the second of the movable opening / closing member and the buffer member formed on these mounting surfaces. A convex portion; and a concave portion formed on the other of the movable opening and closing member and the buffer member and into which the second convex portion is fitted.

  By fitting the second convex portion into the concave portion, it is possible to more reliably attach (fix) the buffer member to the movable opening / closing member.

  Since this invention was set as said structure, generation | occurrence | production of the noise when a movement opening / closing member moves to the obstruction | occlusion position can be suppressed.

It is sectional drawing along the axial direction which shows the structure of the vibration isolator which concerns on 1st Embodiment of this invention, and has shown the state which has a movement opening / closing member in an open position. It is sectional drawing along the axial direction which shows the structure of the vibration isolator which concerns on 1st Embodiment of this invention, and has shown the state which has a plunger main body in the obstruction | occlusion position. It is sectional drawing which shows the structure of the partition metal fitting and movement opening / closing member in the vibration isolator which concerns on 1st Embodiment of this invention, and has shown the state which has a movement opening / closing member in an open position. It is sectional drawing which shows the structure of the partition metal fitting and movement opening / closing member in the vibration isolator which concerns on 1st Embodiment of this invention, and has shown the state which has a movement opening / closing member in a obstruction | occlusion position. It is a disassembled perspective view which shows the structure of the partition metal fitting and movement opening / closing member in the vibration isolator which concerns on 1st Embodiment of this invention. It is a perspective view which shows the structure of the orifice member in the vibration isolator which concerns on 1st Embodiment of this invention. The shock absorbing ring in the vibration isolator which concerns on 1st Embodiment of this invention is shown, (A) is a perspective view, (B) is sectional drawing of radial direction. It is sectional drawing which shows partially the structure of the partition metal fitting and movement opening / closing member in the vibration isolator which concerns on 2nd Embodiment of this invention, (A) is a state in which a movement opening / closing member exists in an open position, (B) is a movement The state which has an opening-and-closing member in a closed position is shown. The shock absorbing ring in the vibration isolator which concerns on 2nd Embodiment of this invention is shown, (A) is a perspective view, (B) is sectional drawing of radial direction. It is sectional drawing which shows partially the structure of the partition metal fitting and movement opening / closing member in the vibration isolator which concerns on 3rd Embodiment of this invention, (A) is the state which has a movement opening / closing member in an open position, (B) is movement The state which has an opening-and-closing member in a closed position is shown. It is sectional drawing which shows partially the structure of the partition metal fitting and movement opening / closing member in the vibration isolator which concerns on 4th Embodiment of this invention, (A) is the state which has a movement opening / closing member in an open position, (B) is movement The state which has an opening-and-closing member in a closed position is shown. The shock absorbing ring in the vibration isolator which concerns on 4th Embodiment of this invention is shown, (A) is a perspective view, (B) is sectional drawing of radial direction.

  Hereinafter, a vibration isolator according to an embodiment of the present invention will be described with reference to the drawings. In the figure, symbol S represents the axial center of the apparatus, and the following description will be made with the direction along the axial center S as the axial direction of the apparatus.

  1 and 2 show a vibration isolator 10 according to an embodiment of the present invention. As shown in FIG. 1, the vibration isolator 10 is provided with an outer cylinder fitting 12 formed in a thin cylinder on the outer peripheral side thereof, and a mounting fitting 20 is substantially coaxial on the inner circumference side of the outer cylinder fitting 12. Is arranged. An annular flange portion 14 is formed at the upper end portion of the outer cylinder fitting 12 so as to bend toward the outer peripheral side, and a caulking portion 16 is formed at the lower end portion that is bent in a tapered shape toward the inner peripheral side when the apparatus is assembled. In the middle of the flange portion 14 and the caulking portion 16, a throttle portion 18 bent in a V-shaped cross section toward the inner peripheral side is formed over the entire circumference. The vibration isolator 10 is connected to the vehicle body side of the vehicle via the holder fitting when the outer cylinder fitting 12 is inserted into a cup-shaped holder fitting (not shown).

  The upper end side of the mounting bracket 20 is formed in a columnar shape having a substantially constant outer diameter, and the lower end side is formed in a substantially truncated cone shape whose outer diameter is reduced in a tapered shape downward. A screw hole 22 is drilled in the metal fitting 20 along the axis S from the upper end surface toward the lower end side. The vibration isolator 10 is connected and fixed to the engine side of the vehicle via a fastening member such as a bolt screwed into the screw hole 22 of the mounting bracket 20 and a bracket stay.

  In the vibration isolator 10, a rubber elastic body 24 formed in a substantially thick ring shape is disposed between the outer cylinder fitting 12 and the mounting fitting 20. The outer peripheral surface of the rubber elastic body 24 is vulcanized and bonded to the upper side of the narrowed portion 18 on the outer peripheral surface of the outer tube fitting 12, and the inner peripheral surface is vulcanized and bonded to the lower end side of the outer peripheral surface of the mounting bracket 20. . Thereby, the rubber elastic body 24 elastically connects the outer cylinder fitting 12 and the mounting fitting 20.

  The rubber elastic body 24 is formed in a shape in which a cross section of the rubber elastic body 24 widens while being inclined downward from the mounting bracket 20 toward the outer cylindrical bracket 12. As a result, a substantially frustoconical concave portion 26 whose inner diameter becomes narrower from the lower side to the upper side is formed in the central portion of the lower surface of the rubber elastic body 24. The rubber elastic body 24 is integrally formed with a stopper section 28 having a rectangular cross section extending from the outer peripheral portion of the upper end to the outer peripheral side. The stopper section 28 is a peripheral portion of the flange portion 14 of the outer cylinder fitting 12. It is vulcanized and bonded to a part along the direction. The stopper 28 abuts against a bracket stay or the like to limit the displacement on the engine side when a large relative displacement occurs on the engine side along the axial direction with the vibration isolator 10 attached to the vehicle. At the same time, the generation of collision noise is prevented.

  The rubber elastic body 24 is integrally formed with an inner cushion portion 30 that covers the lower end portion of the mounting bracket 20 on the inner peripheral portion of the lower end thereof, and a step portion 32 on the inner peripheral side of the throttle portion 18 of the outer cylindrical bracket 12. Are integrally formed. The stepped portion 32 has a flat bottom surface and is supported by the throttle portion 18 so that deformation in the axial direction from the outer peripheral side is limited. The rubber elastic body 24 is integrally formed with a thin cylindrical covering portion 34 that extends downward from the outer peripheral portion of the lower end of the step portion 32. The covering portion 34 is vulcanized and bonded to the outer cylinder fitting 12 so as to cover the lower end side on the inner peripheral surface of the outer cylinder fitting 12.

  A partition fitting 36 (see FIG. 3) formed in a substantially thick disc shape as a whole is fitted into the vibration isolator 10 on the inner peripheral side of the outer cylinder fitting 12. The partition metal 36 abuts its outer peripheral surface on the upper surface side of the stepped portion 32 and presses the outer peripheral surface against the inner peripheral surface of the outer cylindrical metal member 12 via the covering portion 34. In addition, an annular support cylinder 38 is fitted into the vibration isolator 10 below the partition metal 36 on the inner peripheral side of the outer cylinder metal 12. The upper end side of the support cylinder 38 is brought into contact with the outer peripheral portion of the lower surface of the partition fitting 36, and the outer peripheral surface is pressed against the inner peripheral surface of the outer cylinder fitting 12 through the covering portion 34. In the vibration isolator 10, the inner and outer diameters of the caulking portion 16 of the outer cylinder fitting 12 are reduced from the upper end side toward the lower end side in a state where the partition fitting 36 and the support cylinder 38 are fitted in the outer cylinder fitting 12. It is bent as follows. As a result, the partition fitting 36 and the support cylinder 38 are fixed between the stepped portion 32 (the throttle portion 18) and the caulking portion 16 in the outer cylinder fitting 12.

  The support cylinder 38 is provided with a diaphragm 40 formed into a thin disk shape with a rubber material on the inner peripheral side thereof. The outer peripheral edge of the diaphragm 40 extends over the entire circumference of the support cylinder 38. It is vulcanized and bonded to the peripheral surface. As a result, a substantially cylindrical space (liquid chamber space) in which the upper end side along the axial direction is closed by the rubber elastic body 24 and the lower end side is closed by the diaphragm 40 is formed in the outer cylinder fitting 12. The liquid chamber space is partitioned by the partition metal 36 into a main liquid chamber 42 having the rubber elastic body 24 as a part of the partition wall and a sub liquid chamber 44 having the diaphragm 40 as the partition wall. The main liquid chamber 42 and the sub liquid chamber 44 are filled with a liquid such as water and ethylene glycol, respectively.

  Here, the inner volume of the main liquid chamber 42 changes (expands / contracts) with the elastic deformation of the rubber elastic body 24, and the diaphragm 40 has a sufficiently small load in the direction of expanding / contracting the inner volume of the sub liquid chamber 44. It can be deformed by (hydraulic pressure).

  As shown in FIG. 5, the partition member 36 is provided with an orifice member 46 formed of a synthetic resin or a metal material such as aluminum on the lower side, and a bottomed cylindrical shape on the upper side of the orifice member 46. A lid member 48 is disposed. The orifice member 46 is formed in a thick bottomed cylindrical shape whose lower surface is closed by the bottom plate portion 50. The bottom plate portion 50 is provided with a plurality of (for example, four) circulation openings 52 formed in a substantially fan shape whose dimension along the circumferential direction extends from the inner peripheral side toward the outer peripheral side, and FIG. As shown, a thick cylindrical boss portion 54 is integrally formed on the inner peripheral side of the circulation opening 52.

  As shown in FIG. 3, the dimension along the axial direction of the boss portion 54 is larger than the thickness of the bottom plate portion 50, and protrudes from the upper surface portion and the lower surface portion of the bottom plate portion 50. A circular concave seat receiving hole 56 is opened in the center of the upper surface of the boss portion 54, and a lower end portion of a coil spring 90 described later is inserted into the seat receiving hole 56. The boss portion 54 is provided with a clearance hole 58 penetrating between the bottom surface of the seat receiving hole 56 and the lower surface of the boss portion 54. The inner diameter of the escape hole 58 is smaller than the inner diameter of the seat receiving hole 56, and a guide cylinder portion 82 of a moving opening / closing member 78 described later is inserted into the escape hole 58 so as to be detachable.

  As shown in FIG. 5, the orifice member 46 is formed with a fitting insertion portion 60 having an outer diameter smaller than that of the lower end side at the upper end portion of the outer peripheral surface thereof. The orifice member 46 is formed with a concave groove portion 64 extending along a spiral direction inclined at a predetermined angle with respect to the circumferential direction between the step portion 62 and the lower end portion on the outer peripheral surface. The groove portion 64 circulates the outer peripheral surface of the orifice member 46 over a number of times slightly more than two.

  In the orifice member 46, as shown in FIG. 6B, a part of the insertion portion 60 is cut out in a concave shape in the axial direction, and one end portion on the main liquid chamber 42 side along the longitudinal direction of the groove portion 64 is formed. A communication path 66 that communicates with the upper surface of the orifice member 46 is formed. Further, as shown in FIG. 6C, the orifice member 46 is partially cut out in a rectangular shape in the axial direction, and the other end portion along the longitudinal direction of the groove portion 64 is formed in the orifice member 46. A communication path 68 that communicates with the lower surface is formed.

  The groove portion 64 is provided with a common orifice portion 70 in a section from one end on the main liquid chamber 42 side to the middle portion in the longitudinal direction (spiral direction), and a dedicated orifice on the sub liquid chamber 44 side with respect to the common orifice portion 70. A portion 72 is provided. Here, the common orifice portion 70 and the dedicated orifice portion 72 have the same depth along the radial direction, but the common orifice portion 70 has a width along the axial direction of the axis of the dedicated orifice portion 72. It is longer than the width along the direction by a predetermined length. As a result, the common orifice portion 70 has a cross-sectional area larger than the cross-sectional area of the dedicated orifice portion 72, and the cross-sectional area of the common orifice portion 70 is the frequency of idle vibration (for example, 18) generated during idling operation of the vehicle. To 30 Hz) and amplitude.

  As shown in FIG. 6 (A), the orifice member 46 is located in the vicinity of the boundary between the common orifice portion 70 and the dedicated orifice portion 72 in the groove portion 64 from the bottom surface portion on the inner peripheral side of the groove portion 64. An orifice opening 74 penetrating to the peripheral surface is formed. The orifice opening 74 is formed in a slot shape elongated in the circumferential direction. Here, the opening area of the orifice opening 74 is equal to or larger than the cross-sectional area of the common orifice portion 70.

  The orifice opening 74 has a substantially semicircular shape at both ends along the inner peripheral end thereof, and an increase in the flow resistance of the liquid in the vicinity of both ends is suppressed. Further, the cross-sectional shape along the liquid flow direction at the inner peripheral edge portion (edge portion) of the orifice opening 74 may be a convex semicircular shape or wedge shape so as to suppress an increase in liquid flow resistance at the edge portion.

  As shown in FIG. 6C, a cylindrical space is formed on the inner peripheral side of the orifice member 46, and a cylinder member 76 in which a moving opening / closing member 78 described later is accommodated is provided in the cylindrical space. The inner space is a cylinder chamber 76S. As shown in FIG. 5, the movable opening / closing member 78 is formed in a thick disk shape, and a pressurizing space 130 (FIG. 3) that is a small space on the main liquid chamber 42 side along the axial direction of the cylinder chamber 76S. And an orifice space 132 (see FIG. 4), which is a small space on the side of the auxiliary liquid chamber 44. The moving opening / closing member 78 has an edge 79 on the lower end side of the outer peripheral surface thereof extending in parallel with the longitudinal direction of the orifice opening 74.

  As shown in FIG. 3, the movable opening / closing member 78 is formed with an annular recess 80 extending in the circumferential direction between a peripheral portion and a central portion on the lower surface side. The movable opening and closing member 78 is integrally formed with a thick cylindrical guide tube portion 82 projecting downward from the central portion of the lower surface thereof, and a bearing penetrating the central portion of the guide tube portion 82 in the axial direction. A hole 84 is drilled. The movable opening / closing member 78 is coaxially formed with a cylindrical seat receiving portion 86 having a diameter larger than that of the guide tube portion 82 at the base end portion of the guide tube portion 82. The movable opening / closing member 78 is formed with a circular concave relief 88 at the center of the upper surface thereof.

  As shown in FIG. 3, the moving opening / closing member 78 is inserted into the cylinder chamber 76S of the orifice member 46, and is movable (slidable) in the axial direction along the inner peripheral surface of the cylinder chamber 76S. At this time, the moving opening / closing member 78 is coaxially inserted into the seat receiving hole 56 and the escape hole 58 of the orifice member 46 at the front end side of the guide cylinder portion 82, Since the diameter is smaller than the inner diameter of the hole 56 and the escape hole 58, the moving opening / closing member 78 does not contact the bottom plate portion 50 of the orifice member 46 and is in a predetermined range along the axial direction (a closed position and an open position described later). Between) and move. In addition, a coil spring 90 as an urging member is disposed between the bottom plate portion 50 of the orifice member 46 and the moving opening / closing member 78 in the partition member 36.

  The upper end of the coil spring 90 is fitted on the outer peripheral side of the seat receiving portion 86 of the moving opening / closing member 78, and the lower end thereof is inserted into the seat receiving hole 56 of the orifice member 46. In this state, the coil spring 90 has its upper end surface (upper seat surface) pressed against the peripheral edge of the seat receiving portion 86 of the moving opening / closing member 78 and its lower end surface (lower seat surface) is the bottom surface of the seat receiving hole 56. It is kept in a compressed state by the movable opening / closing member 78 and the bottom plate part 50. As a result, the coil spring 90 always urges the moving opening / closing member 78 upward (to the main liquid chamber 42 side).

  As shown in FIG. 3, in the partition member 36, the lid member 48 is fitted and fixed to the outer peripheral side of the fitting insertion portion 60 in the orifice member 46. As a result, the upper end side of the cylinder chamber 76 </ b> S of the orifice member 46 is closed by the top plate portion 92 of the lid member 48. As shown in FIG. 5, the lid member 48 has a circular insertion hole 94 formed in the center portion of the top plate portion 92 and a plurality of fan-shaped ( In this embodiment, four valve seat openings 96 are formed. These valve seat openings 96 are arranged so as to have a symmetrical positional relationship (point symmetry) about the axis S. Further, as shown in FIG. 5, the lid member 48 has a notch 98 formed on the outer peripheral portion thereof so as to face the communication path 66 (see FIG. 6B) on the upper end side of the orifice member 46. The common orifice part 70 communicates with the sub liquid chamber 44 through the notch part 98 and the communication path 66 of the lid member 48.

  As shown in FIG. 5, a substantially disc-shaped holder member 100 is disposed between the lid member 48 and the movable opening / closing member 78 in the partition metal 36, and between the holder member 100 and the lid member 48. A substantially disc-shaped valve body 102 is interposed between the two. As shown in FIG. 3, the holder member 100 is formed with a valve body holder 104 having a bottomed cylindrical shape with a shallow bottom at the center, and extends from the upper end of the valve body holder 104 to the outer peripheral side. The protruding annular flange portion 106 is bent. The holder member 100 is formed with a plurality of communication openings 108 each formed in a fan shape on the outer periphery of the bottom plate portion 105 of the valve body holder 104.

  As shown in FIG. 3, the holder member 100 is integrally formed with a thick disc-shaped boss portion 110 at the center portion of the bottom plate portion 105, and an axis S from the center portion of the lower surface of the boss portion 110. A round rod-shaped guide rod 120 protruding downward along is integrally formed. A circular concave fitting insertion hole 112 is formed on the upper surface side of the boss portion 110. Here, between the top plate portion 92 of the lid member 48 and the bottom plate portion 105 of the holder member 100, a valve body that is a disk-shaped space having a constant thickness along the axial direction on the outer peripheral side of the fitting insertion hole 112. A storage chamber 114 is formed, and the valve body 102 is stored in the valve body storage chamber 114.

  The valve body 102 is molded from a rubber composition such as NR, NBR, etc., and the upper surface side is formed into a flat shape, and the lower surface side is formed in a slope shape slightly inclined upward from the inner peripheral side to the outer peripheral side. The thickness along the axial direction gradually decreases from the inner peripheral side toward the outer peripheral side. The valve body 102 has a circular convex protrusion 116 formed at the center of the upper surface and a circular convex protrusion 118 formed at the center of the lower surface. The valve body 102 has a projection 116 on the upper surface side inserted into the insertion insertion hole 94 of the lid member 48, and a projection 118 on the lower surface side inserted into the insertion insertion hole 112 of the holder member 100. Thereby, the valve body 102 is positioned coaxially with the holder member 100 and the lid member 48, and the movement in the radial direction is restricted.

  The valve body 102 is compressed in the axial direction between the top plate portion 92 of the lid member 48 and the bottom plate portion 105 of the holder member 100 in the vicinity of the peripheral portions of the projections 116 and 118. As a result, the upper surface portion of the valve body 102 is pressed against the lower surface side of the top plate portion 92 of the lid member 48 with a predetermined pressure (preload), and between the lid member 48 and the holder member 100 in the axial direction. The movement of is restricted. In the valve body 102, a portion on the outer peripheral side of the compressed portion can be bent and deformed downward.

  As shown in FIG. 3, the valve body 102 has its outer peripheral end positioned on the outer peripheral side of the valve member opening 96 in the lid member 48 along the radial direction, and the outer periphery of the communication opening 108 of the holder member 100. It is located on the inner peripheral side from the end. Thereby, the valve body 102 closes the valve seat opening 96 in a state where the upper surface portion thereof is in pressure contact with the top plate portion 92 (closed state), and the outer peripheral side is downward as shown by a two-dot chain line in FIG. When bent and deformed and separated from the top plate portion 92 (open state), the valve seat opening 96 is in communication with the communication opening 108 via the valve body storage chamber 114, and the main liquid chamber 42 is in the valve body storage chamber 114. And communicates with the cylinder chamber 76S in the partition member 36. That is, the valve body 102, the lid member 48, and the holder member 100 housed in the valve body housing chamber 114 constitute a check valve 128 between the main liquid chamber 42 and the cylinder chamber 76S. The valve 128 allows the liquid to flow only from the main liquid chamber 42 into the cylinder chamber 76S (pressurizing space 130), but prevents the liquid from flowing out from the pressurizing space 130 into the main liquid chamber 42.

  The guide rod 120 of the holder member 100 is inserted into the bearing hole 84 of the moving opening / closing member 78 so as to be relatively slidable along the axial direction. Here, when one of the guide cylinder portion 82 and the guide rod 120 in which the bearing hole 84 is formed is made of metal, the other is a material whose Young's modulus such as resin is different by a predetermined value or more and whose friction resistance is small. It is preferable to form by. Alternatively, one or both of the inner peripheral surface of the bearing hole 84 and the outer peripheral surface of the guide rod 120 may be coated with a material having lubricity and high wear resistance to suppress the frictional resistance. Further, the guide rod 120 protrudes to the lower side of the orifice member 46 through the seat receiving hole 56 and the escape hole 58 of the orifice member 46, and the guide rod 120 has a central portion of the diaphragm 40. A central connecting portion 41 formed in a circular convex shape is fixed to the portion by vulcanization adhesion.

  The orifice space 132 of the cylinder chamber 76S always communicates with the auxiliary liquid chamber 44 through the plurality of flow openings 52 of the orifice member 46, the seat receiving holes 56, and the escape holes 58. Further, in the vibration isolator 10, as shown in FIG. 1, the outer peripheral side of the groove portion 64 in the orifice member 46 is blocked by the inner peripheral surface of the outer cylinder fitting 12 through the covering portion 34. As a result, a shake orifice 122 that is an elongated space along the spiral direction is formed in the groove portion 64, and one end portion of the shake orifice 122 has a communicating path 66 of the orifice member 46 and a notch portion 98 of the lid member 48. The other end is connected to the secondary liquid chamber 44 via the communication path 68 of the orifice member 46.

  Here, the shake orifice 122 is configured by the entire groove portion 64 including the common orifice portion 70 and the dedicated orifice portion 72 having different cross-sectional areas and the communication passages 66 and 68. The shake orifice 122 has a path length and a cross-sectional area, that is, a liquid flow resistance, set so as to correspond to a shake vibration (for example, 9 to 15 Hz) that is a relatively low frequency vibration of the input vibration. Tuning).

  The common orifice part 70 in the groove part 64 forms a part of the idle orifice 124 corresponding to idle vibration (for example, 18 to 30 Hz) that is vibration in a high frequency range relatively to the shake vibration. The idle orifice 124 includes a common orifice portion 70, an orifice opening 74, and an orifice space 132 in the orifice member 46, and is set so that its path length and cross-sectional area, that is, the flow resistance of the liquid corresponds to idle vibration ( Tuning). Here, the flow resistance of the liquid in the idle orifice 124 is smaller than the flow resistance of the liquid in the shake orifice 122.

  As shown in FIG. 2, in the vibration isolator 10, when the movable opening / closing member 78 moves (lowers) to the closed position, the orifice opening 74 of the orifice member 46 is blocked by the outer peripheral surface of the movable opening / closing member 78, and the common orifice unit 70. Is not in communication with the orifice space 132. As a result, the main liquid chamber 42 and the sub liquid chamber 44 communicate with each other only through the shake orifice 122.

  In the vibration isolator 10, as shown in FIG. 1, when the moving opening / closing member 78 moves (rises) to the open position, the moving opening / closing member 78 moves away from the orifice opening 74, and the orifice opening 74 is opened. Is in communication with the orifice space 132. As a result, the main liquid chamber 42 and the sub liquid chamber 44 communicate with each other through both the shake orifice 122 and the idle orifice 124. However, when the liquid pressure in the main liquid chamber 42 changes, When the liquid that has flowed into the common orifice portion 70 reaches the vicinity of the boundary with the dedicated orifice portion 72, the liquid preferentially enters the orifice space 132 through the orifice opening 74 having a smaller flow resistance than the dedicated orifice portion 72. In addition, the liquid flowing into the common orifice part 70 through the orifice opening 74 preferentially passes through the common orifice part 70 whose liquid flow resistance is smaller than that of the dedicated orifice part 72 and into the main liquid chamber 42. Exit. Thereby, in the vibration isolator 10, when the moving opening / closing member 78 is in the open position, the liquid flows between the main liquid chamber 42 and the sub liquid chamber 44 substantially only through the idle orifice 124.

  As shown in FIG. 3, the movable opening / closing member 78 is formed with a plurality of (two in the present embodiment) hydraulic pressure release passages 126 penetrating in the axial direction in the radial intermediate portion. These hydraulic pressure release paths 126 allow the liquid in the pressurizing space 130 closed from the outside to pass through the orifice space 132 when the moving opening / closing member 78 in the closed position moves to the open position side by the urging force of the coil spring 90. The movable opening / closing member 78 can be moved to the open position side by preventing the fluid pressure in the pressurized space 130 from rising.

  As shown in detail in FIGS. 3, 4, and 7 (A) and 7 (B), the lower end portion 78 </ b> L of the movable opening / closing member 78 is an annular buffer rubber molded from a rubber composition such as NR or NBR. A ring 142 is attached. In FIG. 7B, the shock-absorbing rubber ring 142 is shown as a ring-shaped radial cross section. In this radial direction, the shock-absorbing rubber ring 142 has a substantially circular cross section.

  On the other hand, an annular accommodation groove 144 that accommodates the substantially upper half of the shock-absorbing rubber ring 142 is formed in the lower end portion 78L of the moving opening / closing member 78 over the entire circumference. The shock-absorbing rubber ring 142 is fixed to the movable opening / closing member 78 by heat welding or adhesion in a state where the upper half is accommodated in the accommodation groove 144. When the shock absorbing rubber ring 142 is thus attached to the movable opening / closing member, the substantially lower half of the shock absorbing rubber ring 142 is exposed below the lower end portion 78L. In particular, in this embodiment, the movable opening / closing member 78 is made of resin. Therefore, the rubber cushion ring 142 made of rubber can be integrally formed with the moving opening / closing member 78 by heat welding or the like.

  The thickness of the buffer rubber ring 142 (diameter D1 shown in FIG. 7B) is as shown in FIGS. 2 and 4 when the movable opening / closing member 78 is moved to the closed position in the attached state to the movable opening / closing member 78. Considering the relationship between the shape of the moving opening / closing member 78 and the moving stroke so that the shock absorbing rubber ring 142 contacts the inner lower surface of the cylinder member 76 (hereinafter, this surface is referred to as “contacted surface 76T” in particular). It has been decided. Therefore, the position of the contacted surface 76T is the front end side in the moving direction when the moving opening / closing member 78 moves (this movement occurs, for example, when the hydraulic pressure in the main liquid chamber 42 increases). It is “the tip side in the moving direction of the member”. When the moving opening / closing member 78 moves in this way, the buffer rubber ring 142 contacts the contacted surface 76T. From this point of view, the radial cross section of the buffer rubber ring 142 is not limited to the circular shape shown in FIG. 7B, and may be an ellipse or a polygon.

  Next, the operation of the vibration isolator 10 according to the embodiment of the present invention will be described.

  For example, when an engine in the vehicle is operated, vibration generated by the engine acts on the vibration isolator 10. In the vibration isolator 10, it is transmitted to the rubber elastic body 24 via the mounting bracket 20, and the rubber elastic body 24 is elastically deformed. At this time, the rubber elastic body 24 acts as a main vibration absorber, and the vibration is absorbed by the vibration absorbing action based on the internal friction or the like of the rubber elastic body 24, so that the vibration transmitted to the vehicle body side via the outer cylinder fitting 12 is reduced. .

  In vehicles such as automobiles, the engine generates idle vibrations that are relatively high-frequency vibrations during idling, and shake vibrations that are relatively low-frequency vibrations when the engine is traveling at a predetermined speed or higher. Is generated.

  In the vibration isolator 10, a part of the shake orifice 122 on the main liquid chamber 42 side is a common orifice part 70 that forms part of the idle orifice 124. An orifice opening 74 communicating with the orifice space 132 of the cylinder chamber 76S is formed between the common orifice portion 70 and the dedicated orifice portion 72 that is a part of the shake orifice 122 on the side of the sub liquid chamber 44. For this reason, the main liquid chamber 42 and the sub liquid chamber 44 communicate with each other by a shake orifice 122 including a common orifice portion 70 and a dedicated orifice portion 72, and further, by an idle orifice 124 including a common orifice portion 70 and an orifice space 132. Communicate with each other.

  Further, in the vibration isolator 10, when the moving opening / closing member 78 moves from the open position to the closed position against the urging force of the coil spring 90 by the hydraulic pressure in the pressurizing space 130 of the cylinder chamber 76S, the orifice opening 74 is closed. The orifice opening 74 is opened when the coil spring 90 is returned from the closed position to the open position by the urging force of the coil spring 90, so that the moving opening / closing member 78 in the open position passes through the check valve 128 from the main liquid chamber 42 to the pressurized space. When moved to the closed position by the liquid pressure supplied into 130, the liquid moves back and forth between the main liquid chamber 42 and the sub liquid chamber 44 through only the shake orifice 122 with the elastic deformation of the rubber elastic body 24. When the movable opening / closing member 78 in the closed position returns to the open position by the biasing force of the coil spring 90, the shake orifice 122 and the eye Both of the fluid orifices 124 are opened, but with the elastic deformation of the rubber elastic body, the main liquid chamber 42 and the sub liquid chamber preferentially pass through the idle orifice 124 having a relatively small liquid flow resistance. Liquid goes back and forth between 44 and 44.

  That is, in the vibration isolator 10, when a shake vibration having a relatively low frequency and a large amplitude is input, the rubber elastic body 24 is elastically deformed by the shake vibration, and a relatively large liquid is contained in the main liquid chamber 42. As the pressure changes, the liquid flows from the main liquid chamber 42 into the pressurized space 130 through the check valve 128 when the hydraulic pressure in the main liquid chamber 42 periodically increases, and the hydraulic pressure in the pressurized space 130 is also main. The pressure in the liquid chamber 42 rises to an equilibrium pressure that is substantially in equilibrium with the rising liquid pressure.

  Here, in the vibration isolator 10, the biasing force of the coil spring 90 is set to be smaller than the value corresponding to the hydraulic pressure (equilibrium pressure) in the pressurizing space 130 when the shake vibration is input. When vibration is input, the moving opening / closing member 78 intermittently moves from the open position to the closed position side against the biasing force of the coil spring, and is held at the closed position by the hydraulic pressure in the pressurizing space 130.

  Therefore, in the vibration isolator 10, when shake vibration is input, the liquid moves back and forth between the main liquid chamber 42 and the sub liquid chamber 44 only through the shake orifice 122 in accordance with the elastic deformation of the rubber elastic body 24. Since the input vibration (shake vibration) can be absorbed by the viscous resistance and pressure loss of the liquid passing through the shake orifice 122, low-frequency vibration transmitted from the engine side to the vehicle body side in the vehicle can be reduced.

  At this time, the flow resistance of the liquid in the shake orifice 122 is set (tuned) so as to correspond to the frequency and amplitude of the shake vibration, so that the main liquid chamber 42 and the sub liquid chamber 44 pass through the shake orifice 122. A resonance phenomenon (liquid column resonance) occurs in the liquid flowing back and forth, and shake vibration can be absorbed particularly effectively by the action of the liquid column resonance.

  In the vibration isolator 10, when idle vibration having a relatively high frequency and a small amplitude is input, the rubber elastic body 24 is elastically deformed by the idle vibration and a relatively small liquid is contained in the main liquid chamber 42. Since the pressure changes, the liquid flows from the main liquid chamber 42 into the pressurized space through the check valve 128 when the hydraulic pressure in the main liquid chamber 42 periodically increases, and the hydraulic pressure in the pressurized space 130 increases. As a result, the pressure reaches the equilibrium pressure that is approximately in equilibrium with the hydraulic pressure (maximum value) during the ascent in the main liquid chamber 42.

  However, in the vibration isolator 10, the urging force of the coil spring 90 is set to be larger than the value corresponding to the equilibrium pressure in the pressurizing space 130 at the time of idling vibration input, whereby the moving opening / closing member 78 is opened. When in the position, it is held in the open position by the biasing force of the coil spring 90, and when in the closed position, it moves (returns) from the closed position to the open position by the biasing force of the coil spring 90.

  When the moving opening / closing member 78 in the closed position moves to the open position side by the biasing force of the coil spring 90, the hydraulic pressure release path 126 formed in the moving opening / closing member 78 is pressurized from the outside. Since the liquid in the space 130 flows out into the orifice space 132, an increase in the fluid pressure in the pressurizing space 130 is prevented, and the moving opening / closing member 78 can be moved smoothly toward the open position with low movement resistance.

  Therefore, in the vibration isolator 10, when the idle vibration is input, the main liquid chamber 42 preferentially passes through the idle orifice 124 having a small liquid flow resistance with respect to the shake orifice 122 in accordance with the elastic deformation of the rubber elastic body 24. Since the liquid flows back and forth between the gas and the auxiliary liquid chamber 44, the input vibration (idle vibration) can be absorbed by the viscous resistance and pressure loss of the liquid flowing through the idle orifice 124, so that the vibration is transmitted from the engine side to the vehicle body side. Can reduce idle vibration.

  At this time, since the flow resistance of the liquid in the idle orifice 124 is set (tuned) so as to correspond to the frequency and amplitude of the idle vibration, the main liquid chamber 42 and the sub liquid chamber 44 pass through the idle orifice 124. A resonance phenomenon (liquid column resonance) occurs in the liquid flowing back and forth, and idle vibration can be absorbed particularly effectively by the action of the liquid column resonance.

  As a result, according to the vibration isolator 10, the main liquid chamber 42 and the sub liquid chamber 44 are communicated with each other without using a valve mechanism that operates in response to external control and power supply such as an electromagnetic solenoid or a pneumatic solenoid. The orifice to be switched can be switched to either the shake orifice 122 or the idle orifice 124 according to the frequency of the input vibration, using the change in the hydraulic pressure in the main liquid chamber 42 as the driving force.

  Further, in the vibration isolator 10, a part of the shake orifice 122 on the main liquid chamber 42 side is the common orifice part 70 that forms a part of the idle orifice 124. Since a part of 124 can be formed, the two shake orifices 122 and the idle orifice 124 can be efficiently arranged in a narrow space in the outer cylinder fitting 12, and the apparatus size can be efficiently reduced.

  Further, in the vibration isolator 10, the shake orifice 122 (the common orifice portion 70 and the dedicated orifice portion 72) and a part of the idle orifice 124 (the common orifice portion 70) are formed on the outer peripheral surface of the orifice member 46 formed in a substantially cylindrical shape. In addition, by providing the cylinder chamber 76S (orifice space 132) on the inner peripheral side of the orifice member 46, the size of the orifice member 46 (partition metal fitting 36) is restrained from increasing in size in the axial direction and the radial direction. Since the shake orifice 122 that requires a long path length and the idle orifice 124 that requires a large cross-sectional area can be efficiently arranged in the partition metal fitting 36, as a result, the size of the entire apparatus can also be reduced efficiently.

  Here, in the vibration isolator 10 of the present embodiment, the shock absorbing rubber ring 142 is attached to the lower end portion 78L of the moving opening / closing member 78. Therefore, when the movable opening / closing member 78 moves to the closed position, the buffer rubber ring 142 contacts the contacted surface 76T of the cylinder member 76. That is, the lower end portion 78L of the moving opening / closing member 78 does not directly contact the contacted surface 76T of the cylinder member 76. For this reason, generation | occurrence | production of abnormal noise can be suppressed compared with the structure in which the buffer rubber ring 142 is not provided, that is, the structure in which the lower end portion 78L of the movable opening / closing member 78 directly contacts the contacted surface 76T of the cylinder member 76. .

  8A and 8B partially show a vibration isolator 210 according to the second embodiment of the present invention. The second embodiment differs from the first embodiment in the structure of a shock absorbing rubber ring 214 that is a shock absorbing member according to the present invention. In the second embodiment, since the entire configuration of the vibration isolator 210 is the same as that of the first embodiment except for the structure of the shock absorbing rubber ring 214, the entire configuration of the vibration isolator 210 is not shown. . In the following description, the same components, members, and the like as those in the first embodiment are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted.

  As shown in detail in FIGS. 9A and 9B, the shock-absorbing rubber ring 214 of the second embodiment is formed in an annular shape as a whole, but its upper portion is reduced in a stepped shape upward. The small-diameter portion 218 and the large-diameter portion 216 are provided. In other words, an annular protrusion having a smaller diameter than the large diameter portion 216 protrudes from above the large diameter portion 216. On the other hand, the lower part of the movable opening / closing member 78 is formed in a cylindrical shape, and forms a cylindrical inner circumference continuously from the lower end 78L constituting one end (lower end) in the axial direction and the end face 78L. An inner surface portion 78N is provided. The outer diameter D2 of the small diameter portion 218 is approximately the same as or slightly larger than the inner diameter of the inner surface portion 78N of the moving opening / closing member 78. In addition, the outer diameter D3 of the large diameter portion 216 is approximately the same as the outer diameter of the movable opening / closing member 78. When the buffer rubber ring 214 is attached to the moving opening / closing member 78, the outer peripheral surface 218 </ b> G of the small diameter portion 218 comes into close contact with the inner surface portion 78 </ b> N of the moving opening / closing member 78. Further, the upper end surface 216 </ b> U of the large diameter portion 216 is in close contact with the lower end portion 78 </ b> L of the moving opening / closing member 78. That is, the shock-absorbing rubber ring 214 has a substantially staircase shape including a large-diameter portion 216 and a small-diameter portion 218, so that it can move not only on the upper end surface 216 U of the large-diameter portion 216 but also on the outer peripheral surface 218 G of the small-diameter portion 218 The member 78 can be tightly sealed. The upper end surface 216U of the large diameter portion 216 is the first contact surface according to the present invention. Moreover, the outer peripheral surface 218G of the small diameter part 218 is the second contact surface according to the present invention.

  As shown in detail in FIG. 9B, from the lower end of the large-diameter portion 216 of the buffer rubber ring 214, a buffer protrusion 220 having a substantially inverted triangular cross section is formed annularly over the entire circumference. . When the moving opening / closing member 78 moves from the open position to the closed position, first, the tip of the buffer protrusion 220 contacts the contacted surface 76T. At the initial contact stage, only the tip of the buffer protrusion 220 is in contact with the contacted surface 76T, so the contact area is small. When the buffer rubber ring 142 further moves downward from this state, the tip of the buffer protrusion 220 is elastically crushed as shown in FIG. 8B, and the contact area with the contacted surface 76T gradually increases. Go.

  Also in the vibration isolator 210 of the second embodiment configured as described above, the vibration isolating effect for both the idle vibration and the fake vibration acting from the engine is the same as that of the vibration isolator 10 of the first embodiment. Demonstrate things.

  Particularly, in the shock absorbing rubber ring 214 of the second embodiment, a shock absorbing protrusion 220 having a substantially inverted triangular cross section is formed toward the contacted surface 76T. Therefore, when the moving opening / closing member 78 moves from the open position to the closed position, first, the tip of the buffer protrusion 220 contacts the contacted surface 76T. The buffer protrusions 220 are formed in a substantially inverted triangular shape, and the contact area with the contacted surface 76T at the initial contact is small. Therefore, the movement opening / closing member 78 is allowed to move downward even after the contact, compared to the contact with a large contact area from the initial contact. As a result, it is possible to secure a long moving stroke of the moving opening / closing member 78, and as a result, the adhesion of the buffer rubber ring 214 to the contacted surface 76T is enhanced. Further, the effect of suppressing an inadvertent liquid flow (leakage) between the buffer rubber ring 214 and the contacted surface 76T is also enhanced.

  Further, in the shock absorbing rubber ring 214 of the second embodiment, the movable opening / closing member 78 is tightly sealed at two places, the upper end surface 216U of the large diameter portion 216 and the outer peripheral surface 218G of the small diameter portion 218. Therefore, for example, the sealing performance is enhanced as compared with a configuration in which the shock-absorbing rubber ring is in close contact with the movable opening / closing member at only one place. The effect of suppressing an inadvertent liquid flow (leakage) between the buffer rubber ring 214 and the moving opening / closing member 78 is also enhanced.

  It should be noted that the shape of the buffer protrusion 220 is not limited to the substantially inverted triangular cross section shown in FIG. For example, the cross section may be substantially square or semicircular.

  FIGS. 10A and 10B partially show the vibration isolator 310 provided with the shock absorbing rubber ring 314 according to the third embodiment of the present invention. The third embodiment differs from the second embodiment in the structure of a shock absorbing rubber ring 314 that is a shock absorbing member according to the present invention. In the third embodiment, the entire configuration of the vibration isolator 310 is the same as that of the first embodiment and the second embodiment, except for the structure of the shock absorbing rubber ring 314, and thus the illustration is omitted. In the following description, the same components and members as those in the first embodiment or the second embodiment are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted.

  In the buffer rubber ring 314 of the third embodiment, two large and small buffer protrusions 220 (outer buffer protrusions 220S and inner buffer protrusions 220U) that are concentric and different in diameter are formed annularly from the lower end of the large-diameter portion 216. Has been.

  Therefore, the vibration isolator 310 according to the third embodiment has substantially the same function and effect as the vibration isolator 210 according to the second embodiment. In particular, two shock-absorbing protrusions 220S and 220U are formed on the shock-absorbing rubber ring 314. Therefore, it is possible to more effectively suppress the phenomenon that the liquid inadvertently flows between the buffer rubber ring 314 and the contacted surface 76T (see FIG. 10B).

  In addition, since the load when the shock absorbing rubber ring 314 comes into contact with the contacted surface 76T is received by the two shock absorbing protrusions 220S and 220U, the durability of the shock absorbing rubber ring 314 is improved compared to the second embodiment. To do.

  Of course, from this viewpoint, the number of the buffer protrusions 220 may be further increased to three or more.

  11A and 11B partially show a vibration isolator 410 provided with a shock absorbing rubber ring 414 according to a fourth embodiment of the present invention. The fourth embodiment differs from the second embodiment in the structure of a shock absorbing rubber ring 414 that is a shock absorbing member according to the present invention. In addition, in 4th Embodiment, except the structure of the buffer rubber ring 414, since the whole structure of the vibration isolator 410 is made the same as 1st Embodiment and 2nd Embodiment, it abbreviate | omits illustration. In the following description, the same components and members as those in the first embodiment or the second embodiment are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted.

  The shock absorbing rubber ring 414 of the fourth embodiment has substantially the same shape as the shock absorbing rubber ring 214 of the second embodiment, but further, as shown in detail in FIG. 12, the upper end surface 216U of the large diameter portion 216. In addition, a plurality of fitting protrusions 416 are formed upward. Each of the fitting protrusions 416 is formed in a substantially cylindrical shape. A plurality of fitting protrusions 416 are arranged at regular intervals in the circumferential direction.

  On the other hand, a fitting hole 418 is formed at a position corresponding to the fitting protrusion 416 in the lower end portion 78L of the shock absorbing rubber ring 214 of the moving opening / closing member 78. The inner diameter of the fitting hole 418 is slightly smaller than the outer diameter of the fitting protrusion 416, and the fitting protrusion 416 is slightly reduced in diameter and inserted into the fitting hole 418 to be fitted. Therefore, in the fourth embodiment, the buffer rubber ring 414 can be more reliably fixed to the moving opening / closing member 78.

  The shapes of the fitting protrusions 416 and the fitting holes 418 are not limited to those described above. In short, the cushioning rubber ring and the movable opening / closing member are partially fitted so that the fixing is more reliable. I just need it. Accordingly, the fitting protrusion 416 and the fitting hole 418 may have a shape (annular shape) continuous over the entire circumference. Further, the fitting protrusion 416 may be formed in the moving opening / closing member 78, and the fitting hole 418 may be formed in the shock absorbing rubber ring 414.

  In the vibration isolator according to each embodiment of the present invention, one of the two orifices (the first restriction passage and the second restriction passage) is a shake orifice 122 corresponding to shake vibration, and the other is corresponding to idle vibration. Although the idle orifice 124 is used, the two first restriction passages and the second restriction passages do not necessarily correspond to shake vibration and idle vibration, and the first restriction passage corresponds to vibration in a relatively low frequency range. Thus, it is sufficient that the second restriction passage corresponds to vibration in a relatively high frequency range.

  Further, in the vibration isolator of the present invention, the longitudinal direction of the orifice opening 74 is made coincident with the circumferential direction centered on the axis S, but the longitudinal direction of the orifice opening 74 is aligned with the circumference centered on the axis S. The direction in which the edge portion 79 of the moving opening / closing member 78 extends may be inclined with respect to the circumferential direction, and may coincide with the longitudinal direction of the orifice opening 74 inclined with respect to the circumferential direction.

  In the vibration isolator of the present invention, the mounting bracket 20 is connected to the engine side and the outer cylinder bracket 12 is connected to the vehicle body side. Conversely, the mounting bracket 20 is connected to the vehicle body side. The outer cylinder fitting 12 may be connected to the engine side.

  In the vibration isolator of the present invention, the liquid is supplied from the main liquid chamber 42 into the pressurizing space 130 through the check valve 128 when the liquid pressure in the main liquid chamber 42 increases, and the liquid pressure in the pressurizing space 130 is reduced. The pressure is increased to an equilibrium pressure corresponding to the upper limit value of the hydraulic pressure in the main fluid chamber 42, and the movable opening / closing member 78 is moved from the open position to the closed position by the hydraulic pressure (positive pressure) in the pressurizing space 130 when shake vibration is input. However, on the contrary, the check valve is configured so that the liquid can flow only from the pressurizing space 130 to the main liquid chamber 42, and the liquid is passed through the check valve when the liquid pressure in the main liquid chamber 42 decreases. By causing the pressurized space 130 to flow into the main fluid chamber 42, the fluid pressure in the pressurized space 130 is reduced to an equilibrium pressure corresponding to the lower limit value of the fluid pressure in the main fluid chamber 42. The movable opening / closing member 78 is closed from the open position by the hydraulic pressure (negative pressure) in the pressure space 130. It may be to move to the position.

  In the above case, the vibration isolator is configured such that the opening / closing member 78 is biased downward along the axial direction by the coil spring 90, and the opening / closing member 78 is in the lower limit position (open position). 74 is opened, and the orifice opening 74 is configured to be opened when it rises from the lower limit position to the upper limit position (closed position) against the urging force of the coil spring 90 due to the negative pressure in the pressurizing space 130. The

10 Vibration isolator 12 Outer cylinder fitting (first mounting member)
20 Mounting bracket (second mounting member)
24 Rubber elastic body (elastic body)
36 Partition bracket (support member)
40 Diaphragm 42 Main liquid chamber 44 Sub liquid chamber 70 Common orifice part 72 Dedicated orifice part 74 Orifice opening 76 Cylinder member 76S Cylinder chamber 78 Moving opening / closing member 78L Lower end (end face part)
78N Inner surface portion 79 Edge portion 90 Coil spring (biasing member)
102 Valve body 122 Shake orifice (passage)
124 Idle orifice (passage)
126 Hydraulic pressure release path 128 Check valve 130 Pressurizing space 132 Orifice space 142 Buffer rubber ring (buffer member)
144 Housing Groove 210 Vibration Isolator 214 Buffer Rubber Ring (Buffer Member)
216 Large diameter portion 216U Upper end surface 218 Small diameter portion 218G Outer peripheral surface 220 Buffer protrusion (convex portion)
220S outer shock-absorbing protrusion 220U inner shock-absorbing protrusion 310 vibration isolator 314 shock-absorbing rubber ring (buffer member)
410 Anti-vibration device 414 Buffer rubber ring (buffer member)
416 Mating protrusion 418 Mating hole

Claims (6)

A first attachment member coupled to one of the vibration generating portion and the vibration receiving portion;
A second attachment member coupled to the other of the vibration generating portion and the vibration receiving portion;
An elastic body disposed between the first mounting member and the second mounting member;
A main liquid chamber in which a liquid is sealed with the elastic body as a part of a partition wall, and the internal volume changes with elastic deformation of the elastic body;
A secondary liquid chamber in which liquid is enclosed and the internal volume can be expanded and contracted;
A plurality of passages communicating with each other between the main liquid chamber and the sub liquid chamber;
A cylinder member which is provided between the main liquid chamber and the sub liquid chamber and forms a cylinder chamber in which liquid is sealed;
A check valve that allows liquid to move only from the main liquid chamber toward the cylinder chamber;
An orifice opening provided in the cylinder member so as to communicate the cylinder chamber and a part of the passage;
A moving opening and closing member that opens and closes the orifice opening by moving in the cylinder chamber in accordance with a fluid pressure fluctuation in the main liquid chamber and selects the passage to switch between a shake mode and an idle mode;
An urging member that elastically supports the moving opening and closing member so as to be reciprocally movable in the cylinder chamber;
A buffer member that is provided on the movable opening and closing member and cushions in contact with the contacted portion of the cylinder member located on the distal end side in the movement direction of the movable opening and closing member;
A vibration isolator.   The anti-vibration device according to claim 1, further comprising a protrusion provided on the buffer member and protruding toward the contacted portion.   The vibration isolator according to claim 2, wherein a plurality of the convex portions are provided. The side of the moving opening / closing member to which the buffer member is attached includes an end surface portion constituting one end of the moving opening / closing member, and an inner surface portion continuous from the end surface portion,
The vibration isolator according to any one of claims 1 to 3, wherein the buffer member includes a first contact surface that contacts the end surface portion and a second contact surface that contacts the inner surface portion. The buffer member is made of rubber,
The vibration isolator according to any one of claims 1 to 4, wherein the movable opening / closing member is made of resin. A second convex portion formed on these mounting surfaces in any one of the movable opening and closing member and the buffer member;
A concave portion formed on the other of the movable opening and closing member and the buffer member and fitted with the second convex portion;
The vibration isolator of any one of Claims 1-5 which has these.

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