JP5530816B2 - Fluid filled vibration isolator - Google Patents

Description

  The present invention relates to an anti-vibration device applied to an engine mount or the like of an automobile, and more particularly to a fluid-filled vibration-proof device that exhibits an anti-vibration effect due to a fluid action of a fluid enclosed inside.

  Conventionally, as a type of a vibration isolator which is interposed between members constituting a vibration transmission system such as a power unit of an automobile and a vehicle body and connects these members with each other for vibration isolation, Japanese Patent Application Laid-Open No. 57-9340 There is known a fluid-filled vibration isolator as disclosed in (Patent Document 1) and the like. Such a fluid-filled vibration isolator connects the first mounting bracket and the second mounting bracket with a main rubber elastic body, and includes a pressure receiving chamber and a flexible membrane into which vibration is input due to deformation of the main rubber elastic body. The balance chamber is allowed to change in volume and communicated with an orifice passage.

  By the way, in such a fluid-filled vibration isolator, since the frequency region where the vibration isolating effect based on the fluid flow action through the orifice passage is exhibited is limited to a specific frequency region tuned in advance, It is difficult to obtain effective anti-vibration characteristics. Conventionally, this problem can be prevented by changing and controlling the wall spring rigidity of the fluid chamber using negative pressure as disclosed in Japanese Patent Application Laid-Open No. 61-59035 (Patent Document 2). Switching vibration characteristics, or selectively switching a plurality of orifice passages tuned to different frequency ranges with an actuator-driven switching valve as disclosed in JP-A-8-21480 (Patent Document 3) It has been proposed to switch the anti-vibration characteristics.

  However, in the conventional fluid-filled vibration isolator shown in Patent Document 2 and Patent Document 3, a switching valve and an actuator for operating the switching valve for controlling the connection to the negative pressure source or switching the orifice passage, Since a control device is required, there is a problem that the device is complicated and large in size, and the characteristic switching control is difficult.

Japanese Unexamined Patent Publication No. 57-9340 JP-A-61-59035 JP-A-8-21480

  Here, the present invention has been made in the background of the above-described circumstances, and the problem to be solved is to provide a fluid-filled vibration isolator whose vibration isolating characteristics can be switched according to input vibration. It is to provide with structure.

According to a first aspect of the present invention, a pressure receiving chamber and a wall portion in which a first mounting member and a second mounting member are connected by a main rubber elastic body, and a part of the wall portion is configured by the main rubber elastic body. Formed an equilibrium chamber partly composed of a flexible membrane, sealed an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and formed an orifice passage communicating the pressure receiving chamber and the equilibrium chamber with each other. In the fluid filled type vibration damping device, the outer peripheral portion is fixedly supported by the second mounting member, whereby the pressure in the pressure receiving chamber is exerted on one surface and the pressure in the equilibrium chamber is exerted on the other surface. A movable rubber film that is arranged in a state that is elastically deformed in accordance with a pressure difference exerted on both surfaces of the movable rubber film is formed, and a through-hole that is open in an initial state is formed in the movable rubber film. The circumference of the through hole in at least one opening portion A valve piece for covering the through hole based from a portion projecting on the surface of the movable rubber film to the elastic deformation forms integrally the movable rubber film, the valve piece from the opening of the through hole in the initial shape The through hole is separated and held in a communicating state, and the valve piece is elastically deformed based on a relative pressure fluctuation between the pressure receiving chamber and the equilibrium chamber, and is formed in the opening of the through hole. A fluid-filled vibration isolator that approaches and blocks the through-hole .

  In the fluid-filled vibration isolator of this aspect, fluid flow through the through-hole formed in the movable rubber film is generated based on the relative pressure fluctuation between the pressure receiving chamber and the equilibrium chamber caused when vibration is input. . The relative pressure between the pressure receiving chamber and the equilibrium chamber is also applied to the valve piece and the rubber elastic membrane directly or as fluid flow pressure. When the operating pressure increases, the valve piece and / or the movable rubber membrane is elastically deformed. Based on this, the opening portion of the through hole is covered with the valve piece. Therefore, depending on the input vibration, if the fluid pressure flowing through the through hole is large, such as low frequency or large amplitude vibration or small amplitude or high frequency vibration, the rubber elastic membrane will penetrate. With the hole closed, fluid flow through the through hole is greatly limited or substantially prevented.

  Accordingly, the anti-vibration property based on the fluid flow action through the through-hole, which is exhibited by allowing fluid flow through the through-hole formed in the movable rubber film, and the through-hole through The anti-vibration characteristics that are effective when the fluid flow is blocked and the anti-vibration effect based on the fluid flow action through the orifice passage is effective, with a simple structure that does not require a special external pressure source or actuator. It can be switched and exhibited according to the input vibration.

  Moreover, in the fluid-filled vibration isolator of this aspect, based on the relative pressure difference between the pressure receiving chamber and the equilibrium chamber in a state where the through hole is covered with the valve piece and fluid flow through the through hole is blocked. The entire elastic deformation of the movable rubber film is caused. Therefore, based on the elastic deformation of the entire movable rubber film, a predetermined vibration-proofing effect such as a low dynamic spring effect due to the pressure absorbing action and fluid flow action of the pressure receiving chamber can be effectively exhibited.

  According to a second aspect of the present invention, in the fluid-filled vibration isolator according to the first aspect, an inner portion of the fluid rubber film is supported along the outer peripheral portion supported by the second mounting member. A thin wall portion extending in the circumferential direction is formed on the circumferential side, and the through hole is formed on the inner circumferential side of the thin wall portion.

  In the fluid-filled vibration isolator of this aspect, the thin portion is formed on the outer peripheral portion of the movable rubber film, and the through hole is formed on the inner peripheral side from this thin portion. When the pressure difference between the pressure receiving chamber and the equilibrium chamber is exerted on the movable rubber film under the state of being covered with a piece, in the movable rubber film, the region on the inner peripheral side of the thin wall portion where the spring is softened (that is, the through hole The entire large area including the portion where the film is formed is elastically deformed with a large area. As a result, the low dynamic spring effect up to the high frequency range based on the elastic deformation of the movable rubber film can be more effectively exhibited.

  According to a third aspect of the present invention, in the fluid-filled vibration isolator according to the first or second aspect, the movable rubber film has an opening portion of the through-hole in the opposite bank portion with respect to the valve piece. A seal piece projecting at a projecting height smaller than the valve piece is integrally formed on the surface of the rubber film.

  In the fluid-filled vibration isolator of this aspect, when the valve piece closes the through hole, the opposite shore portion of the through hole with which the valve piece abuts is softened by the seal piece, which accompanies the hitting of the valve piece. The impact sound and impact are reduced, and the accuracy of closing the through hole with the valve piece is improved (the sealing performance of the contact portion is improved). Can be. In addition, an opposite bank part means the opposite bank part of the formation area of the valve piece in the peripheral part of a through-hole. Moreover, the above-mentioned effect can be exhibited more effectively by the sealing piece having a tapered cross-sectional shape.

  According to a fourth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to third aspects, the through hole has a long hole shape in plan view of the movable rubber film. In addition, the valve piece protrudes from one of the pair of long side peripheral portions extending in the long side direction and opposed in the short side direction in the through hole, and the valve piece is the pair in the through hole. The through-hole is covered by being brought into contact with the other of the long side peripheral portions.

  In the fluid-filled vibration isolator of this aspect, the through hole has a long hole shape, so that the flow passage cross-sectional area of the through hole is secured in the long hole direction and the valve piece extends in the long hole direction of the through hole. By doing so, it is possible to facilitate elastic deformation of the through hole in the valve piece in the cover direction, and it is possible to stabilize the cover operation for the through hole of the valve piece.

  According to a fifth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to fourth aspects, the movable rubber film has a proximal end opposite to the through hole in the valve piece. A cutout groove extending along the portion is formed.

  In the fluid-filled vibration isolator of this aspect, regardless of the wall thickness of the movable rubber film, by appropriately adjusting the size, shape, depth, etc. of the hollow groove formed in the base end portion of the valve piece, It is possible to easily adjust the elastic deformation in the direction of covering the through hole of the valve piece. Therefore, the degree of freedom in designing the condition for switching the through hole by the valve piece, in other words, the condition for switching the anti-vibration characteristic based on the cover of the through hole by the valve piece can be further increased.

  According to a sixth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to fifth aspects, the valve pieces are provided in both opening portions of the through hole in the movable rubber film, respectively. It is a thing.

  In the fluid-filled vibration isolator of this aspect, both the through-holes are present under any relative pressure state, in which the pressure receiving chamber has a negative pressure relative to the equilibrium chamber and a positive pressure. Based on the cover-covering action of the through-hole by the valve body provided in the opening portion, the through-hole can be closed. Therefore, the switching effect of the anti-vibration characteristic exhibited based on the blocking of the through hole can be achieved more remarkably.

  According to a seventh aspect of the present invention, in the fluid filled type vibration damping device according to any one of the first to sixth aspects, one surface of the rubber elastic film is directly exposed to the pressure receiving chamber. The other surface of the rubber elastic membrane is directly exposed to the equilibrium chamber, and the rubber elastic membrane constitutes a part of a partition wall that partitions the pressure receiving chamber and the equilibrium chamber.

  In the fluid filled type vibration isolator of this aspect, the relative pressure difference between the pressure receiving chamber and the equilibrium chamber due to vibration input is directly exerted on both surfaces of the movable rubber film, so that the movable rubber film and the valve formed there This pressure difference is exerted more efficiently on the piece, and it is possible to more reliably and efficiently obtain the anti-vibration characteristics based on the intended operation of the valve piece and the action of the movable rubber film. Become.

  According to an eighth aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to sixth aspects, the surface of the movable rubber film to which the pressure of the pressure receiving chamber is exerted and the pressure of the equilibrium chamber An intermediate chamber is formed on either side of the surface on which the pressure is exerted, and a high frequency orifice that communicates the intermediate chamber with the pressure receiving chamber or the equilibrium chamber is tuned to a higher frequency region than the orifice passage. The pressure of the pressure receiving chamber or the equilibrium chamber is applied to the movable rubber film from the high frequency orifice through the intermediate chamber.

  In the fluid-filled vibration isolator of this aspect, at the time of vibration input, fluid flow through the high-frequency orifice occurs based on the fluid flow through the through hole formed in the movable rubber film and the fluid flow based on the elastic deformation of the movable rubber film. Therefore, by utilizing the resonance action of the fluid flowing through such a high-frequency orifice, it is possible to advantageously obtain an anti-vibration effect such as a low dynamic spring effect against vibration in a higher frequency range than the tuning frequency of the orifice passage. It becomes possible.

  Furthermore, in the fluid filled type vibration damping device according to the present invention, a plurality of through holes and a valve body may be provided for the movable rubber film. Further, different elastic deformation characteristics can be set for a plurality of valve bodies, and the conditions for covering the through-holes can be set to be different between the valve bodies. According to this, for example, a plurality of through-holes can be switched to the communication / blocking state individually according to different vibration input conditions.

  Further, when the valve pieces are formed in both the pressure receiving chamber side and the equilibrium chamber side opening portions of one through hole as described in the sixth aspect, similarly, the elastic deformation characteristics of both the valve pieces are the same. That is, the cover operating conditions of the through holes may be different from each other.

  Furthermore, in each of the above aspects of the fluid filled type vibration damping device according to the present invention, in order to limit elastic deformation to the opposite side to the through hole of the valve piece, for example, on the opposite side of the through hole of the valve piece. There may be provided a regulating contact portion that is positioned and abuts when the valve piece is elastically deformed to the opposite side to the through hole and restricts or restricts the deformation of the valve piece to the opposite side. By limiting the deformation of the valve piece to the side opposite to the through hole, the durability of the valve piece can be improved.

  In the fluid filled type vibration isolator constructed according to the present invention, the rubber elastic membrane is penetrated by utilizing the relative pressure difference caused between the pressure receiving chamber and the equilibrium chamber according to the input vibration. The hole is switched between the communication state and the cover state by the valve piece. Therefore, anti-vibration characteristics that are exhibited in a state in which fluid flow through the through-hole formed in the movable rubber film is allowed, and anti-vibration characteristics that are exhibited by preventing fluid flow through the through-hole. However, a simple structure that does not require a special external pressure source, actuator, or the like can be switched according to the input vibration. In addition, under the condition that the through hole is covered with the valve piece, the entire elastic deformation of the movable rubber film is allowed, and therefore, the low movement over a wide frequency range is based on the entire elastic deformation of the movable rubber film. A spring effect can also be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal cross-sectional view which shows the engine mount for motor vehicles as 1st embodiment of this invention. II-II sectional drawing in FIG. The top view of the movable rubber film which comprises the engine mount for motor vehicles shown by FIG. IV-IV sectional drawing in FIG. The longitudinal cross-sectional explanatory drawing for demonstrating the switching operation | movement of the vibration proof characteristic in the engine mount for motor vehicles shown by FIG. The graph which shows the measurement result of the vibration proof characteristic of the engine mount for motor vehicles shown by FIG. 1 with the comparative example. The longitudinal cross-sectional view which shows the principal part of the engine mount for motor vehicles as 2nd embodiment of this invention. The longitudinal cross-sectional view which shows the principal part of the engine mount for motor vehicles as 3rd embodiment of this invention. The longitudinal cross-sectional view which shows the principal part of the engine mount for motor vehicles as 4th embodiment of this invention in an elastically deformed state. The longitudinal cross-sectional view which shows the principal part of the engine mount for motor vehicles as 5th embodiment of this invention.

  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, FIGS. 1 and 2 show an automobile engine mount 10 as a first embodiment of a fluid filled type vibration damping device having a structure according to the present invention. The engine mount 10 has a structure in which a first mounting bracket 12 as a first mounting member and a second mounting bracket 14 as a second mounting member are connected to each other by a main rubber elastic body 16. Yes. The first mounting bracket 12 is attached to the power unit, and the second mounting bracket 14 is attached to the vehicle body, so that the power unit is connected to the vehicle body in a vibration-proof manner and supported. .

  In the following description, the vertical direction means the vertical direction in FIG. 1 in principle. FIG. 1 shows a state before being mounted on an automobile. Under the mounted state, the main rubber elastic body 16 is elastically deformed by the input of a static shared support load of the power unit, and the first mounting bracket 12 and the second mounting bracket 14 are mount center axes (mount elastic main shafts extending vertically in the center in FIG. 1; in this embodiment, the first and second mounting brackets 12 and 14 and the main rubber elastic body 16 equal to the central axis of 16). Furthermore, under such a mounting state, main vibrations to be vibrated are exerted on the first mounting bracket 12 and the second mounting bracket 14 in the mount central axis direction.

  More specifically, the first mounting member 12 has a substantially truncated cone shape in the reverse direction that decreases in diameter toward the lower side. Further, the first mounting member 12 is formed with a bolt hole 22 that opens to the center of the upper end surface and extends downward on the central axis. The first mounting bracket 12 is attached to a power unit (not shown) directly or via an inner bracket or the like by a mounting bolt (not shown) screwed into the bolt hole 22.

  On the other hand, the second mounting bracket 14 has a large-diameter, generally cylindrical shape, and a step portion 24 is formed at an axially intermediate portion thereof. The lower side of the step portion 24 is a small diameter cylindrical portion 26 and the upper side of the step portion 24 is a large diameter cylindrical portion 28.

  The first mounting bracket 12 and the second mounting bracket 14 are arranged on the same central axis, and the first mounting bracket 12 is above the opening on the upper side of the second mounting bracket 14. Are separated from each other. Under such an arrangement, the main rubber elastic body 16 that elastically connects the first mounting bracket 12 and the second mounting bracket 14 has a large-diameter, generally truncated cone shape, and the first portion of the main rubber elastic body 16 has a first shape with respect to the central portion. The mounting bracket 12 is embedded and vulcanized and bonded. Further, the large-diameter cylindrical portion 28 of the second mounting bracket 14 is vulcanized and bonded to the outer peripheral portion of the main rubber elastic body 16. Thereby, the 1st mounting bracket 12 and the 2nd mounting bracket 14 are connected by the main body rubber elastic body 16 distribute | arranged between those opposing surfaces, and this main body rubber elastic body 16 is using the second mounting metal fitting. 14 upper openings are closed fluid tight. The main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first and second mounting brackets 12 and 14.

  The main rubber elastic body 16 is formed with a large-diameter recess 30 that opens to the large-diameter side end face. The large-diameter recess 30 is formed in a reverse mortar shape that expands in the downward direction. By forming the large-diameter recess 30, the main rubber elastic body 16 is connected to the first mounting bracket 12 and the second mounting bracket 12. Between the opposing surfaces of the mounting bracket 14, a thick, substantially tapered cylindrical shape is arranged.

  Furthermore, a seal rubber layer 34 that covers the entire inner peripheral surface of the small-diameter cylindrical portion 26 is vulcanized and bonded to the second mounting member 14 fixed to the outer peripheral portion of the main rubber elastic body 16. The seal rubber layer 34 is integrally formed with the main rubber elastic body 16 vulcanized and bonded to the inner peripheral surface of the large-diameter cylindrical portion 28. A stepped surface facing the lower opening of the second mounting bracket 14 is located at the boundary between the seal rubber layer 34 located near the upper end of the small diameter cylindrical portion 26 and the main rubber elastic body 16 in the second mounting bracket 14. 35 is formed.

  Further, a diaphragm 36 as a flexible film is assembled to the lower opening of the second mounting bracket 14. The diaphragm 36 has a thin and large-diameter substantially disk shape, and has sufficient slack so that elastic deformation can be easily allowed. Further, a cylindrical fixing bracket 37 is vulcanized and bonded to the outer peripheral edge of the diaphragm 36.

  The fixing bracket 37 is fitted into the lower opening of the second mounting bracket 14, and then the diameter of the small diameter cylindrical portion 26 is reduced, so that the fixing bracket 37 attaches the seal rubber layer 34. It is fitted and fixed to the small-diameter cylindrical portion 26 with being sandwiched. As a result, the lower opening of the second mounting bracket 14 is closed by the diaphragm 36.

  Further, as described above, the upper opening of the second mounting bracket 14 is closed by the main rubber elastic body 16 and the lower opening is closed by the diaphragm 36, so that the main rubber elastic body 16 and the diaphragm 36 are closed. Between these axial directions, a fluid sealing region 38 sealed with respect to the external space is defined. The fluid sealing region 38 is sealed with an incompressible fluid made of water, alkylene glycol, polyalkylene glycol, silicone oil, a mixture thereof, or the like. Such an enclosed fluid is not particularly limited, but a low-viscosity fluid of 0.1 Pa · s or less is desirable in order to efficiently obtain a vibration-proofing effect based on the fluid flow action described later.

  A partition member 40 is accommodated in the fluid sealing region 38, and is disposed in a state of spreading in a direction perpendicular to the axis at an axially intermediate portion between the main rubber elastic body 16 and the diaphragm 36. It is supported by the second mounting bracket 14. As a result, the fluid sealing region 38 is partitioned by the partition member 40 and is vertically divided into two. A pressure receiving chamber 42 having a part of the wall portion made of the main rubber elastic body 16 is formed above the partition member 40, and extends between the first mounting bracket 12 and the second mounting bracket 14. When the vibration is input, a pressure fluctuation is generated in the pressure receiving chamber 42 based on the elastic deformation of the main rubber elastic body 16. Also, below the partition member 40, an equilibrium chamber 44 having a part of the wall made of the diaphragm 36 is formed. Based on the elastic deformation of the diaphragm 36, the volume change of the equilibrium chamber 44 is changed. It is easily tolerated.

  Particularly in the present embodiment, the partition member 40 includes an annular orifice member 46, a disk-shaped movable rubber film 48, and an annular plate-shaped holding member 50. The outer peripheral edge of the movable rubber film 48 is gripped between the orifice member 46 and the holding member 50 each made of a highly rigid material such as hard resin or metal, so that the central through hole of the orifice member 46 is formed. A movable rubber film 48 is assembled so as to be blocked.

  The orifice member 46 has an annular shape with a large diameter and a thick wall. Each of the upper circumferential groove 52 and the lower circumferential groove 54 that opens to the outer circumferential surface and extends a little less than one round in the circumferential direction has a shaft. They are formed parallel to each other at a predetermined distance in the direction. The upper circumferential groove 52 and the lower circumferential groove 54 are communicated with each other by a connection hole 56 formed in the partition wall portion of the upper and lower circumferential grooves 52 and 54 at one end corresponding to the circumference. . As a result, the upper circumferential groove 52 and the lower circumferential groove 54 are connected in series with each other, and a circumferential groove is formed that extends as a whole in a circumferential direction with a length of one or more rounds. Further, an upper through hole 58 that opens upward is formed at the end of the upper circumferential groove 52 that is one end of the circumferential groove, and a lower circumference that is the other end of the circumferential groove. A lower through hole 60 that opens downward is formed at the end of the groove 54.

  Then, the orifice member 46 is fitted from the lower opening portion of the second mounting bracket 14, and then, the orifice member 46 sandwiches the seal rubber layer 34 by reducing the diameter of the small diameter cylindrical portion 26. The small diameter cylindrical portion 26 is fixedly fitted. In this assembled state, the orifice member 46 is positioned between the stepped surface 35 of the seal rubber layer 34 and the fixture 37 of the diaphragm 36 in the axial direction. As a result, the outer peripheral openings of the upper and lower circumferential grooves 52 and 54 of the orifice member 46 are fluid-tightly covered with the small-diameter cylindrical portion 26, so that the orifice passage 61 that allows the pressure receiving chamber 42 and the equilibrium chamber 44 to communicate with each other is formed. Is formed.

  In particular, in the present embodiment, the orifice passage 61 is designed so that a high damping effect is exhibited with respect to a low-frequency large-amplitude vibration of about 10 Hz corresponding to an engine shake based on the resonance action of the fluid flowing through the orifice passage 61. The channel length and cross-sectional area are adjusted and tuned.

  On the other hand, the movable rubber film 48 has a disc shape as a whole, as shown in FIGS. 3 to 4 as single items, and the central portion is a disc-shaped thick portion 62. In addition, the outer peripheral portion is an annular plate-shaped thin portion 64, and the outer peripheral portion is thinner than the central portion, so that elastic deformation is easily allowed. Further, an annular holding portion 66 extending over the entire circumference in the circumferential direction is formed on the outer peripheral edge portion of the thin portion 64. The annular holding part 66 has a thickness dimension larger than that of the thin part 64. In particular, in this embodiment, the annular holding part 66 has a circular cross section having a diameter larger than the thickness dimension of the thin part 64 and has a constant cross section over the entire circumference. An annular holding portion 66 that extends in a shape is employed.

  Furthermore, a through hole 68 is formed in the central portion of the thick portion 62. The through hole 68 is formed in the region of the thick portion 62 and does not reach the thin portion 64. The through-hole 68 is long in one radial direction of the thick portion 62 (the vertical direction in FIG. 3 showing the movable rubber film 48 in a plan view) and short in the radial direction perpendicular to the thick hole 62. In particular, in the present embodiment, a rectangular shape having a long side in the vertical direction and a short side in the horizontal direction in FIG. 3 is used. The through hole 68 of the present embodiment is an inclined hole that is slightly inclined with respect to the central axis of the movable rubber film 48 in a cross section parallel to the short side direction shown in FIG. By forming the inclined hole in this way, the technical significance such that the hole length of the through hole 68 can be set larger than the plate thickness of the thick portion 62 and the pressure action on the valve piece (70) described later can be adjusted. However, the through hole 68 of the present invention is not limited to the inclined hole, and may extend parallel to the central axis of the movable rubber film 48 as shown in FIGS.

  In addition, a valve piece 70a is partially formed at the periphery of the opening portion on the upper side of the through hole 68. The valve piece 70 a is integrally formed with the thick portion 62 and is positioned at one of a pair of long side peripheral portions extending in the long side direction and opposed in the short side direction in the through hole 68. It protrudes upward from the opening part on the upper side toward the opening direction. That is, the valve piece 70a has a thin plate shape that extends over the entire length along one long piece side peripheral portion of the through-hole 68, and particularly has a tapered cross-sectional shape in this embodiment.

  Furthermore, the thick wall portion 62 has a cutout groove 72a that is located on the opposite side of the valve piece 70a from the through hole 68 and extends in the long side direction of the through hole 68 along the proximal end portion of the valve piece 70a. Is formed. Due to the cutout groove 72a, the substantial height dimension of the valve piece 70a, that is, the height dimension at which elastic deformation independent of the thick part 62 is allowed is increased. Moreover, the surface on the through hole 68 side of the valve piece 70a is configured as a surface obtained by linearly extending the hole inner surface 74 of the through hole 68, and the elastic deformation of the valve piece 70a is also caused by the thick wall portion. Independent from 62, it is easily allowed.

  In particular, the cutout groove 72a can easily allow the elastic deformation of the fall or curve toward the through hole 68 in the valve piece 70a, while the valve piece 70a faces the opposite side of the through hole 68. When elastically deforming into a fallen shape or a curved shape, the valve piece 70a comes into contact with the opening corner portion of the lightening groove 72a, and the deformation amount of the valve piece 70a on the side opposite to the through hole 68 can be limited.

  On the other hand, the seal piece 76a is integrally formed with the thick portion 62 on the side where the valve piece 70a is not formed among the pair of long side peripheral portions in the opening portion on the upper side of the through hole 68. The seal piece 76a extends along the long-side peripheral portion so as to face the valve piece 70a with the opening portion on the upper side of the through hole 68 sandwiched in the short-side direction. In particular, in the present embodiment, the seal piece 76a has a tapered cross-sectional shape, and the thickness dimension and the protruding height dimension are both smaller than the thickness dimension and the protruding height dimension of the valve piece 70a. Yes.

  Further, in the present embodiment, the valve piece 70a, the fillet groove 72a, and the seal piece 76a as described above formed in the upper opening portion of the through hole 68 are similarly formed in the lower opening portion of the through hole 68. It is formed as a valve piece 70b, a fillet groove 72b, and a seal piece 76b.

  The movable rubber film 48 having such a structure is disposed so as to extend in the direction perpendicular to the axis in the central through hole of the orifice member 46, and the annular holding portion 66 is connected to the orifice member 46 and the holding member 50. And are fixedly held and assembled. That is, the orifice member 46 is formed with an annular upper gripping portion 78 protruding on the inner peripheral surface. On the other hand, the holding member 50 is fixedly assembled so as to overlap the lower surface of the orifice member 46, and constitutes an annular lower gripping portion 80 protruding from the inner peripheral surface of the orifice member 46. The annular holding portion 66 of the movable rubber film 48 is sandwiched in the thickness direction between the upper gripping portion 78 and the lower gripping portion 80 in the axial direction so as to be fluid-tightly supported. The holding member 50 is constituted by, for example, a press-molded metal fitting, and is positioned by being sandwiched in the axial direction between the stepped surface 35 of the seal rubber layer 34 and the fixing metal fitting 37 of the diaphragm 36 together with the orifice member 46. The second mounting bracket 14 is fixedly supported.

  The upper and lower grips 78 and 80 that support the annular holding portion 66 of the movable rubber film 48 have end faces 82 and 84 facing the movable rubber film 48 at the inner peripheral edge from the surface of the movable rubber film 48. It is set as the curved cross-sectional shape which leaves | separates, curving gradually up and down outward. As a result, the movable rubber film 48 is elastically deformed toward the pressure receiving chamber 42 side or the equilibrium chamber 44 side, so that even when the movable rubber film 48 comes into contact with the upper and lower gripping portions 78 and 80, local stress action is avoided and cracks are prevented. Generation prevention is aimed at.

  Further, the inner peripheral end surfaces 82 and 84 of the upper and lower gripping portions 78 and 80 are both positioned on the upper and lower surfaces of the thin portion 64 of the movable rubber film 48, and from the thick portion 62 to the outer peripheral side. They are positioned a predetermined distance apart. In short, on the outer peripheral side of the thick part 62, the thin part 64 is provided over the entire circumference between the gripping parts 78 and 80 over a predetermined radial dimension. Thereby, even in a state where the outer peripheral edge portion of the movable rubber film 48 is fixedly held by the upper and lower holding portions 78 and 80, the movable rubber including the thick portion 62 is formed by the thin portion 64 existing all around the outer peripheral portion. Elastic deformation of the entire membrane 48 toward the pressure receiving chamber 42 side or the equilibrium chamber 44 side can be easily allowed. Then, the pressure and equilibrium of the pressure receiving chamber 42 are respectively passed through the upper and lower surfaces of the movable rubber film 48 through the through hole in the inner peripheral end surface 82 of the gripping portion 78 and the through hole in the inner peripheral end surface 84 of the gripping portion 80. The pressure in the chamber 44 is directly exerted. In short, in the present embodiment, the central portion of the partition member 40 has a single structure of the movable rubber film 48, and the pressure receiving chamber 42 and the equilibrium chamber 44 are formed by the thick part 62 and the thin part 64 of the movable rubber film 48. A part of the partition wall is formed.

  In the engine mount 10 having the above-described structure, when vibration is input while being mounted on a vehicle, a relative pressure fluctuation is induced between the pressure receiving chamber 42 and the equilibrium chamber 44, and accordingly, the orifice passage is provided. The fluid flow through 61 and the through hole 68 is generated. Here, the fluid pressure generated as the fluid flows through the through hole 68 is exerted on the valve pieces 70a and 70b projecting from the upper and lower openings of the through hole 68, and the valve pieces 70a and 70b are elastically deformed. . And when this fluid pressure becomes large, the valve pieces 70a, 70b are greatly elastically deformed, and as shown in FIG. 5, they are greatly deformed toward the through-hole 68 side, and are superposed on the opposite bank side. As a result, the opening of the through hole 68 is covered with the valve pieces 70a and 70b, and the fluid flow through the through hole 68 is inhibited.

  Thus, in the engine mount 10 of the present embodiment, the anti-vibration characteristics that are exhibited by maintaining the through hole 68 in an open state and the through hole 68 are in a cover state according to the input vibration. Therefore, the anti-vibration property exhibited by this is selectively exhibited. Therefore, the thickness of the valve pieces 70a and 70b, the size of the cut-out grooves 72a and 72b, and the like are adjusted so that the elastic deformation of the valve piece 70 is appropriately generated according to the vibration to be vibrated. Thus, according to the input vibration, it is possible to selectively enjoy the anti-vibration characteristic exhibited when the through-hole 68 is open and the anti-vibration characteristic exhibited when the through-hole 68 is covered. is there.

  Specifically, for example, when a low-frequency large-amplitude vibration such as an engine shake is input, a change in acceleration of the vibration and a pressure fluctuation caused in the pressure-receiving chamber 42 is compared with when a medium-frequency medium-amplitude vibration such as an idling vibration is input. The rate (the amount of change per unit time) is large, and the flow rate of fluid that can flow through the through-hole 68 based on the relative pressure fluctuation caused between the pressure receiving chamber 42 and the equilibrium chamber 44 increases. Therefore, the pressure exerted on the valve pieces 70a and 70b by such fluid flow increases, the amount of elastic deformation of the valve pieces 70a and 70b increases, and the through hole 68 is covered with the valve pieces 70a and 70b.

  Thus, for medium frequency medium amplitude vibration such as idling vibration, based on the fluid flow through the through hole 68, that is, the pressure fluctuation in the pressure receiving chamber 42 is released to the equilibrium chamber 44 or the fluid resonance action is utilized. By doing so, it is possible to reduce the mount vibration isolating characteristics and to obtain an effect of improving the anti-vibration performance by the effective vibration insulating action against idling vibration. On the other hand, for low-frequency large-amplitude vibration such as engine shake, the through hole 68 is covered with the valve pieces 70a and 70b, and the escape of pressure fluctuation from the pressure receiving chamber 42 to the equilibrium chamber 44 through the through hole 68 is suppressed. As a result, the relative pressure fluctuation between the pressure receiving chamber 42 and the equilibrium chamber 44 is efficiently generated, so that the amount of fluid flow through the orifice passage 61 is secured, and the high damping effect based on the resonance action of the fluid is ensured. Anti-vibration performance can be advantageously obtained.

  On the other hand, at the time of inputting high-frequency small-amplitude vibration such as traveling noise, the acceleration of vibration and the pressure gradient of the fluid flowing through the through-hole 68 are increased as in the case of inputting engine shake or the like. Therefore, the pressure exerted on the valve pieces 70a and 70b by the fluid flowing through the through hole 68 increases, and the amount of elastic deformation of the valve pieces 70a and 70b increases, and the through hole 68 is covered with the valve pieces 70a and 70b. Become so.

  Under such a condition, the fluid flow through the through hole 68 is substantially prevented. However, since the input vibration exceeds the tuning frequency of the orifice passage 61, the flow resistance of the orifice passage 61 is remarkably increased. Fluid flow through the orifice passage 61 is substantially ineffective. On the other hand, since the relative pressure fluctuation between the pressure receiving chamber 42 and the equilibrium chamber 44 is exerted on the entire upper and lower surfaces of the movable rubber film 48, the movable rubber film 48 is repeatedly applied to the pressure receiving chamber 42 side and the equilibrium chamber 44 side. It bulges and elastically deforms. The input vibration such as a running-over sound flows in the pressure receiving chamber 42 generated by the elastic deformation of the movable rubber film 48 because its amplitude is sufficiently smaller than that of an engine shake or the like. Based on the fluid resonance action and the pressure absorption action of the pressure receiving chamber 42, the vibration isolation performance due to the low dynamic spring effect is exhibited.

  Moreover, the movable rubber film 48 of the present embodiment is capable of elastically deforming substantially the entire thick portion 62 in the central portion when the high frequency small amplitude vibration as described above is input by the thin portion 64 formed in the outer peripheral portion. Therefore, it is possible to effectively enjoy the low dynamic spring effect even in a higher frequency range than the low dynamic spring effect associated with local elastic deformation of the valve piece 70 or the like. Thereby, for example, it is possible to reduce or avoid a high dynamic spring due to the anti-resonance action of the low dynamic spring effect accompanying local elastic deformation of the valve piece 70 or the like.

  Incidentally, as a result of measuring the dynamic spring constant exhibited when the frequency is continuously changed from 20 Hz to 200 Hz by applying vibration with an amplitude of ± 0.05 mm for the engine mount 10 having the structure according to the present embodiment. Is shown in FIG. Note that the engine mount in which the through-hole 68 is not formed in the movable rubber film 48 is also tested under the same conditions, and the measurement result is also shown in FIG. 6 as a comparative example (no through-hole). Although included in the present invention, unlike the present embodiment, a structure in which the entire elastic deformation region of the movable rubber film 48 has a constant thickness without forming the thick part 62 and the thin part 64 in the movable rubber film 48. For the engine mount, the experiment was performed under the same conditions, and the measurement results are also shown in FIG. 6 as a comparative example.

  From the experimental result data of FIG. 6, in both the present example and the comparative example, a sufficiently low dynamic spring effect can be confirmed at around 50 Hz as compared with the comparative example. In addition, in the engine mount 10 of the present embodiment in which the thin portion 64 is formed on the outer periphery of the movable rubber film 48, the high dynamic spring that would be caused by the anti-resonance of about 75 Hz seen in the comparative example is avoided, It is recognized that excellent vibration-proof performance due to the low dynamic spring effect is exhibited in a very wide frequency range exceeding 100 Hz.

  In addition, high-frequency small-amplitude vibrations such as a running-over sound that is expected to have a low dynamic spring effect that is exhibited based on the elastic deformation of the entire movable rubber film 48 is smaller than low-frequency large amplitude vibrations such as an engine shake. Since the input vibration amplitude is small and the pressure fluctuation induced in the pressure receiving chamber 42 is small, for example, the movable rubber film 48 is opposed to one or both surfaces of the movable rubber film 48 with a predetermined distance therebetween. It is also possible to provide a displacement amount limiting plate for limiting the amount of elastic deformation of the bulging toward the pressure receiving chamber 42 side or the equilibrium chamber 44 side. In short, an engine larger than that while allowing the amount of elastic deformation of the movable rubber film 48 to such an extent that the pressure fluctuation of the pressure receiving chamber 42 caused by the input of high-frequency small amplitude vibration such as traveling noise can be sufficiently absorbed. At the time of low-frequency large-amplitude vibration input such as a shake, the movable rubber film 48 abuts against the displacement amount limiting plate to restrict the bulging elastic deformation, thereby suppressing the escape of pressure fluctuation in the pressure receiving chamber 42 and the orifice passage 61. It is also possible to increase the amount of fluid flow, thereby improving the above-described high damping effect based on the resonance action of the fluid flowing in the orifice passage 61.

  As mentioned above, although 1st embodiment of this invention has been explained in full detail, this invention is not limited by the specific description of this embodiment. Several other embodiments of the present invention will be described below. In the engine mounts of these embodiments, members and parts having the same structure as in the first embodiment have the same signs as in the first embodiment. A duplicate description will be omitted by attaching to the drawings.

  FIG. 7 shows a longitudinal sectional view of a main part of an engine mount 90 as a second embodiment of the present invention. In the engine mount 90 of the present embodiment, unlike the first embodiment in which a thin-walled portion that is easily elastically deformed is formed on the outer peripheral portion of the movable rubber film 48, the movable rubber film 48 has a substantially constant thickness throughout. It is made into the disk shape which has a dimension.

  In addition, the upper and lower valve pieces 70a and 70b are formed to protrude from the peripheral edge of one long side of the upper and lower opening portions of the through hole 68 as in the first embodiment. Unlike the valve pieces 70a and 70b, there is no hollowing groove extending along the back (opposite the through hole 68). Instead, thickened portions 92a and 92b are formed integrally behind the valve pieces 70a and 70b to fill and reinforce the rising corners of the valve pieces 70a and 70b.

  The engine mount 90 of this embodiment having such a structure can exhibit the same effects as those of the first embodiment, but the elastic deformation characteristics of the valve pieces 70a and 70b are integrally formed behind each of them. Tuning can be easily performed by appropriately adjusting the size and shape of the increased thickness portions 92a and 92b. Further, since the spring rigidity of at least the base end portions of the valve pieces 70a and 70b is enhanced by the thickened portions 92a and 92b, even if the thin portion is not provided in the outer peripheral portion of the movable rubber film 48, It is possible to reduce or avoid high dynamic springs in the middle to high frequency range due to the anti-resonant action of the local elastic deformation of the valve pieces 70a and 70b in the cover state of the through hole 68.

  FIG. 8 shows a longitudinal sectional view of a main part of an engine mount 96 as a third embodiment of the present invention. In the engine mount 96 of the present embodiment, the through hole 68 of the movable rubber film 48 is linearly penetrated in the thickness direction without being inclined with respect to the central axis of the movable rubber film 48. Further, in the engine mount 96 of the present embodiment, valve pieces 70a and 70a are formed so as to protrude from both long side peripheral portions in the upper and lower opening portions of the movable rubber film 48, respectively. Further, behind the respective valve pieces 70a, 70a, the lightening grooves 72a, 72a are formed in the same manner as in the first embodiment.

  The engine mount 96 of this embodiment having such a structure can exhibit the same effects as those of the first embodiment, but at opposite positions on both sides of the upper opening of the through hole 68 during vibration input. The pair of valve pieces 70a, 70a formed in this manner are elastically deformed in the approaching direction and overlapped with each other so as to cover the through hole 68. Therefore, the amount of elastic deformation of the valve piece 70a can be suppressed, and the switching operation between the cover of the through hole 68 and the communication with the valve piece 70a can be quickly realized, and the effect of improving the durability of the valve piece 70a is also exhibited. Is done. In addition to the elastic deformation of the valve pieces 70a and 70a itself, the through hole 68 may be covered by the elastic deformation of the movable rubber film 48 as shown in FIG. 9 described later, or the elasticity of the valve pieces 70a and 70a itself. The through hole 68 may be covered by the cooperation of the deformation and the elastic deformation of the movable rubber film 48. Thereby, the effect of the present invention can be effectively exhibited.

  FIG. 9 shows a longitudinal sectional view of a main part of an engine mount 98 as a fourth embodiment of the present invention. FIG. 9 schematically shows an operating state in which the pressure in the pressure receiving chamber 42 is increased by the vibration input, and the movable rubber film 48 is elastically deformed so as to bulge toward the equilibrium chamber 44 side. .

  In the engine mount 98 of the present embodiment, a valve piece 100 is formed to protrude from one long side peripheral portion at each of the upper and lower opening portions of the through hole 68 of the movable rubber film 48, and the other. A seal piece 102 is formed so as to protrude from the peripheral portion of the long side. In particular, the valve piece 100 and the seal piece 102 of the present embodiment are formed so as to protrude thicker and with greater spring rigidity than those of the first embodiment. When the vibration is input, the pressure in the pressure receiving chamber 42 is relatively increased as compared with the equilibrium chamber 44, and the movable rubber film 48 is elastically deformed so as to bulge toward the equilibrium chamber 44. As shown in FIG. 9, the protruding direction of the valve piece 100 is inclined with respect to the mount center axis based on the curved distortion accompanying the elastic deformation of the movable rubber film 48 itself. In the present embodiment, since the seal piece 102 is also formed to protrude, the seal piece 102 can be inclined with respect to the mount center axis in the same direction as the valve piece 100 and with an inclination direction opposite to the valve piece 100. Yes.

  As a result, even if the valve piece 100 itself is not elastically deformed, the movable rubber film 48 forming the base portion of the valve piece 100 is elastically deformed, so that the valve piece 100 is inclined and deformed to the through hole 68 side. Thus, the through hole 68 is covered by the contact with the seal piece 102. Therefore, even in the engine mount 98 of this embodiment having such a structure, the same operational effects as those of the first embodiment can be exhibited. On the other hand, when the pressure in the pressure receiving chamber 42 is decreased relative to the equilibrium chamber 44, the movable rubber film 48 is elastically deformed so as to bulge upward, and the cover of the through hole 68 is similarly formed. Realized.

  Further, FIG. 10 shows an engine mount 106 as a fifth embodiment of the present invention. In the engine mount 106 of the present embodiment, a partition plate 108 is fixedly provided on the partition member 40 so as to be overlapped in the axial direction, and the partition plate 108 is located on the pressure receiving chamber 42 side with respect to the movable rubber film 48. They are arranged facing each other at a distance. As a result, an intermediate chamber 110 independent from both the pressure receiving chamber 42 and the equilibrium chamber 44 is formed between the movable rubber film 48 and the partition plate 108.

  A part of the wall portion of the intermediate chamber 110 is formed of a movable rubber film 48, and the intermediate chamber 110 and the equilibrium chamber 44 are partitioned with the movable rubber film 48 interposed therebetween.

  In addition, a communication hole 112 that allows the intermediate portion in the length direction of the orifice passage 61 to communicate with the intermediate chamber 110 is formed in the intermediate portion in the length direction of the upper circumferential groove 52 formed in the orifice member 46. As a result, the orifice passage 61 is partially used to form a high-frequency orifice 114 that allows the pressure receiving chamber 42 and the intermediate chamber 110 to communicate with each other. The high-frequency orifice 114 is tuned to a higher frequency range than the orifice passage 61, and is based on the resonance action of the fluid that causes the high-frequency orifice 114 to flow, for example, with respect to medium-frequency medium amplitude vibration corresponding to idling vibration. It is tuned to exhibit the low dynamic spring effect.

  In such an engine mount 106, the pressure on the pressure receiving chamber 42 side is exerted on the movable rubber film 48 through the high frequency orifice 114 and the intermediate chamber 110. Then, based on the relative pressure fluctuation between the pressure receiving chamber 42 and the equilibrium chamber 44 exerted on the movable rubber film 48, the anti-vibration effect based on the fluid flow action through the through hole 68, and the through hole 68 has the valve pieces 70a and 70b. The anti-vibration effect exhibited under the condition of being covered with can be selectively exerted based on the communication / blocking of the through-hole 68 by the valve pieces 70a and 70b as in the first embodiment.

  In the present invention, the movable rubber film 48 is configured by configuring the partition member 40 described in the fifth embodiment upside down including the partition plate 108, the intermediate chamber 110, and the high frequency orifice 114 as a whole. The intermediate chamber 110 is formed on the side of the equilibrium chamber 44 of the movable rubber film 48, and the intermediate chamber 110 is communicated with the equilibrium chamber 44 through the high-frequency orifice 114. Also good. Even if it forms with such a structure, the effect similar to 5th embodiment may be exhibited.

  In the present invention, a valve piece may be provided only in one of the upper and lower opening portions of the through hole 68 of the movable rubber film 48. Thus, even when the valve piece is formed only in one of the upper and lower opening portions of the through hole 68, the switching effect of the anti-vibration characteristic based on the valve piece covering / opening the through hole 68 is effective. Can be demonstrated.

  When the valve piece is formed only in one of the upper and lower opening portions of the through hole 68 as described above, it is advantageous to form the valve piece in the upper opening portion rather than the lower opening portion. The valve piece that is covered and formed in the upper opening portion has a through-hole formed by the valve piece that is held in an open state due to a significant negative pressure that is induced in the pressure receiving chamber 42 when an excessive impact load is input when overcoming a step. This is because it is possible to quickly escape based on the fluid flow allowed to flow in from the equilibrium chamber 44 through 68 and to reduce or avoid the occurrence of vibration and impact due to cavitation.

10, 86, 90, 96, 98, 106: engine mount (fluid-filled vibration isolator), 12: first mounting bracket (first mounting member), 14 second mounting bracket (second mounting member) ), 16 Main rubber elastic body, 34: Seal rubber layer, 36: Diaphragm (flexible membrane), 42: Pressure receiving chamber, 44: Equilibrium chamber, 48: Movable rubber membrane, 61: Orifice passage, 68: Through hole, 70 : Valve piece, 72: fillet groove, 76: seal piece, 100: valve piece, 102: seal piece, 110: intermediate chamber, 114: high frequency orifice

Claims (8)

The first mounting member and the second mounting member are connected by a main rubber elastic body, and a pressure receiving chamber in which a part of the wall portion is configured by the main rubber elastic body and a part of the wall portion is a flexible film. In a fluid-filled vibration isolator that forms a configured equilibrium chamber, encloses an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and forms an orifice passage that interconnects the pressure receiving chamber and the equilibrium chamber.
The outer peripheral portion is fixedly supported by the second mounting member so that the pressure in the pressure receiving chamber is exerted on one surface and the pressure in the equilibrium chamber is exerted on the other surface. Provide a movable rubber film that is elastically deformed according to the pressure difference exerted on both sides,
The movable rubber film is formed with a through-hole that is open in an initial state, and at least one opening portion of the through-hole projects from the peripheral portion of the through-hole to the surface of the movable rubber film based on elastic deformation. A valve piece covering the through hole is formed integrally with the movable rubber film ;
The valve piece is separated from the opening of the through hole in an initial shape so as to keep the through hole in communication, and the valve piece has a relative pressure fluctuation between the pressure receiving chamber and the equilibrium chamber. A fluid-filled type vibration isolator which is elastically deformed based on the above and approaches the opening of the through hole to block the through hole .   In the movable rubber film, a thin portion extending in the circumferential direction on the inner peripheral side is formed along the outer peripheral portion supported by the second mounting member, and the inner peripheral side of the thin portion is closer to the inner peripheral side. The fluid-filled vibration isolator according to claim 1, wherein a through hole is formed.   The opening portion of the through hole in the movable rubber film is integrally formed with a seal piece that protrudes at a protruding height smaller than that of the valve piece on the surface of the movable rubber film at a portion opposite to the valve piece. Item 3. The fluid filled type vibration damping device according to Item 1 or 2.   The through hole has a long hole shape in a plan view of the movable rubber film, and extends in the long side direction in the through hole and faces one of a pair of long side side peripheral portions facing in the short side direction. 2. The valve piece is projected, and the through hole is covered by the valve piece coming into contact with the other of the pair of long side peripheral portions of the through hole. The fluid filled type vibration damping device according to any one of?   The fluid-filled type prevention according to any one of claims 1 to 4, wherein the movable rubber film is formed with a hollow groove extending along a base end portion of the valve piece opposite to the through hole. Shaker.   The fluid filled type vibration damping device according to any one of claims 1 to 5, wherein the movable rubber film is provided with the valve pieces at both opening portions of the through hole.   One surface of the rubber elastic membrane is directly exposed to the pressure receiving chamber, and the other surface of the rubber elastic membrane is directly exposed to the equilibrium chamber, and the rubber elastic membrane is connected to the pressure receiving chamber. The fluid-filled vibration isolator according to any one of claims 1 to 6, wherein a part of a partition wall that partitions the equilibrium chamber is configured.   An intermediate chamber is formed on either side of the surface of the movable rubber film to which the pressure of the pressure receiving chamber is applied and the surface of the equilibrium chamber to which pressure is applied, and the intermediate chamber is defined as the pressure receiving chamber or the pressure chamber. A high frequency orifice communicating with the equilibrium chamber is tuned to a higher frequency range than the orifice passage, and the pressure in the pressure receiving chamber or the equilibrium chamber is applied from the high frequency orifice to the movable rubber film through the intermediate chamber. The fluid-filled vibration isolator according to any one of claims 1 to 6.

Images