JPWO2013005261A1 - Fluid filled vibration isolator - Google Patents

Abstract

In order to avoid excessive pressure fluctuations in the pressure receiving chamber, etc., in the fluid-filled vibration isolator with slits on the hydraulic pressure absorbing rubber plate to form elastic tongues, adverse effects on vibration isolation performance against normal input vibration are suppressed. To provide a fluid-filled vibration isolator having a novel structure. A thick reinforcing portion 90 is integrally formed on the elastic tongue 88. Thereby, under normal vibration input conditions, the deterioration of the vibration proof performance due to the provision of the slit 86 and the elastic tongue 88 was suppressed.

Description

  The present invention relates to a fluid-filled vibration damping device that is used, for example, in an engine mount or a suspension mount of an automobile and exhibits a vibration-proofing effect based on a fluid action of a fluid sealed inside.

  Conventionally, as a type of vibration isolator, the first mounting member and the second mounting member are connected by a rubber elastic body, and an incompressible fluid is sealed inside to provide a fluid action such as a resonance action of the fluid. 2. Description of the Related Art A fluid-filled vibration isolator that obtains a vibration isolating effect is known. Specific examples include those described in Japanese Patent No. 2805305 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2009-275910 (Patent Document 2). These fluid-filled vibration damping devices have a pressure receiving chamber in which a part of the wall portion is configured with a main rubber elastic body, and an equilibrium chamber in which a portion of the wall portion is configured with a flexible film, An incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and both chambers are connected to each other by an orifice passage. Then, at the time of vibration input between the first mounting member and the second mounting member, the fluid that is caused to flow in the orifice passage based on the relative pressure fluctuation caused between the pressure receiving chamber and the equilibrium chamber. The anti-vibration effect is exhibited based on the fluid action.

  By the way, the orifice passage can exhibit an effective anti-vibration effect in the frequency range tuned in advance, but the flow resistance becomes particularly large when vibration is input in a higher frequency range than the tuning frequency. Degradation tends to be a problem.

  Therefore, as shown in Patent Documents 1 and 2, there has been proposed a hydraulic pressure absorption mechanism that absorbs pressure fluctuations in the pressure receiving chamber when a high-frequency small-amplitude vibration is input that deviates from the tuning frequency of the orifice passage. Such a hydraulic pressure absorbing mechanism is constituted by a hydraulic pressure absorbing rubber plate disposed between the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber that are exerted on one surface of the hydraulic pressure absorbing rubber plate. When the hydraulic pressure absorbing rubber plate is displaced or deformed based on the pressure difference, small pressure fluctuations in the pressure receiving chamber are absorbed.

  In addition, the hydraulic pressure absorbing rubber plate that constitutes the hydraulic pressure absorbing mechanism is used for the purpose of eliminating sudden pressure fluctuations in the pressure receiving chamber when shocking heavy load is input and preventing abnormal noise caused by cavitation. An elastic tongue is formed by providing a slit penetrating in the plate thickness direction. This elastic tongue piece keeps the slit closed due to the elasticity of the hydraulic pressure absorbing rubber plate, and the elastic tongue piece receives the pressure only when a sudden pressure fluctuation is induced in the pressure receiving chamber by a shocking large load input. Excessive pressure fluctuation in the pressure receiving chamber is avoided by elastically deforming the chamber side or the equilibrium chamber side and opening the slit.

  However, when the present inventor has examined such a fluid-filled vibration isolator having a conventional structure, a normal input that requires an anti-vibration effect or the like by an orifice passage accompanying the provision of a slit in the hydraulic pressure absorbing rubber plate. It has been found that there is a possibility of adversely affecting the vibration isolation performance against vibration. That is, a large pressure fluctuation is not caused in the pressure receiving chamber, and a slit is provided in the hydraulic pressure absorbing rubber plate even at the time of vibration input that only causes the pressure fluctuation of the pressure receiving chamber to such an extent that the slit is originally kept closed. In some cases, the vibration-proof performance is reduced due to the above.

Japanese Patent No. 2805305 JP 2009-275910 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is that a slit is formed in the hydraulic pressure absorbing rubber plate in order to avoid excessive pressure fluctuation in the pressure receiving chamber. An object of the present invention is to provide a novel structure in which an adverse effect on vibration proof performance against normal input vibration is suppressed in a fluid-filled vibration proof device provided with an elastic tongue piece.

  A first aspect of the present invention made to solve such a problem is that the first mounting member and the second mounting member are connected by the main rubber elastic body, and the wall portion is formed by the main rubber elastic body. A pressure receiving chamber in which a part of the pressure receiving chamber is formed, and an equilibrium chamber in which a part of the wall portion is formed of a flexible film are formed, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, In the fluid filled type vibration damping device in which the pressure receiving chamber and the equilibrium chamber are communicated with each other by an orifice passage, a hydraulic pressure absorbing rubber plate is disposed between the pressure receiving chamber and the equilibrium chamber. The pressure of the pressure receiving chamber is exerted on one surface of the pressure absorbing rubber plate, and the pressure of the equilibrium chamber is exerted on the other surface of the hydraulic pressure absorbing rubber plate. Absorbs pressure fluctuation in the pressure receiving chamber based on displacement and deformation of the hydraulic pressure absorbing rubber plate based on the difference On the other hand, an elastic tongue piece is formed on the hydraulic pressure absorbing rubber plate by a slit, and the slit is opened by elastic deformation of the elastic tongue piece to form the pressure receiving chamber and the pressure receiving rubber plate. A short-circuit mechanism for short-circuiting the equilibrium chamber is configured, and a thick reinforcing portion is integrally formed at an intermediate portion in the length direction from the base end portion to the tip end portion of the elastic tongue piece. .

  In the fluid-filled vibration isolator having the structure according to this aspect, a vibration isolating effect based on the resonance action of the fluid flowing through the orifice passage is exhibited with respect to the low frequency large amplitude vibration in which the orifice passage is tuned. In addition, for high-frequency, small-amplitude vibrations, the pressure absorbing function of the pressure receiving chamber based on the displacement and deformation of the hydraulic pressure absorbing rubber plate is exerted, so that a significant high dynamic spring due to substantial closure of the orifice passage is avoided. As a result, a good vibration isolation effect can be obtained. Furthermore, for the input of a shocking heavy load, the elastic tongue formed on the hydraulic pressure absorbing rubber plate is elastically deformed to open the slit, so that the pressure receiving chamber side partitioned by the hydraulic pressure absorbing rubber plate And the equilibrium chamber side are in communication. As a result, a large pressure such as a negative pressure in the pressure receiving chamber is eliminated as quickly as possible, and for example, it is possible to reduce or avoid the generation of abnormal noise and vibration caused by cavitation.

  In addition, in the fluid-filled vibration isolator of this aspect, the elastic tongue piece of the hydraulic pressure absorbing rubber plate is partially thickened to form the reinforcing portion, so that the hydraulic pressure absorbing rubber plate and the elastic tongue are formed. While avoiding a large influence on the overall spring characteristics of the piece, minute elastic deformation or irregular elastic deformation in the elastic tongue piece can be suppressed. As a result, the spring constant is made relatively small at the slit during normal vibration input that requires vibration-proofing effect due to fluid flow through the orifice passage and vibration-proofing effect due to displacement and deformation of the hydraulic pressure absorbing rubber plate. Irregular vibration, minute deformation, or resonance deformation of the tongue piece is suppressed, and the shape of the elastic tongue piece, that is, the entire hydraulic pressure absorbing rubber plate is stabilized. As a result, under normal vibration input conditions where rapid absorption of the pressure in the pressure receiving chamber is not required, adverse effects on vibration isolation performance due to the provision of slits and elastic tongues are suppressed, and the desired vibration isolation effect is achieved. It can be demonstrated effectively.

  That is, as a result of investigation by the present inventor, the elastic tongue formed on the hydraulic pressure absorbing rubber plate may be elastically deformed under specific conditions such as its spring characteristics and the frequency of input vibration, and the shape may become unstable. It was found that there is a possibility that the anti-vibration property may be adversely affected by the elastic tongue piece being deformed in an unstable manner. Based on this knowledge, the present invention has been completed, and in the present invention, stabilization of vibration isolation characteristics can be achieved by suppressing unstable deformation that is not desired in the elastic tongue piece.

  Specifically, instability deformation and minute repetitive deformation such as resonance, which are problems in the elastic tongue, are especially reinforced by reinforcing the middle part in the length direction of the elastic tongue, so that the slit at the time of heavy load input It has been found that the liquid pressure can be effectively suppressed without impairing the action of eliminating the hydraulic pressure. The base end of the elastic tongue is supported by a hydraulic pressure absorbing rubber plate to prevent unstable deformation, and it is necessary to further increase the spring rigidity by providing a reinforcing part on the base end. In addition to being poor, there is a possibility that the deformation resistance to the slit opening operation due to the deformation of the elastic tongue piece becomes too large, which may hinder the slit opening operation. In addition, if a reinforcing portion is provided at the tip of the elastic tongue, the tip mass of the elastic tongue is increased, and the elastic elastic deformation of the elastic tongue itself may be increased. This is because the deformation reaction becomes dull and it is difficult to quickly open the slit.

  In particular, the elastic tongue piece is integrally formed of a rubber elastic body, so that the deformation of the elastic tongue piece can be easily stabilized without increasing the number of parts or complicating the manufacturing process. This can be realized, and the adverse effect on the anti-vibration characteristics exhibited by the displacement and deformation of the movable rubber plate itself can be avoided.

  According to a second aspect of the present invention, in the fluid-filled vibration isolator according to the first aspect, the hydraulic pressure absorbing rubber plate is provided with a plurality of radially extending slits, and the elastic tongue piece is These are formed in the circumferential direction by being positioned between adjacent slits around the radiation center of these slits.

  In the fluid-filled vibration isolator of this aspect, in particular, three or more slits are formed at appropriate intervals in the circumferential direction, for example, at equal intervals, so that a plurality of elastic tongue pieces having a fan-shaped flat plate shape are excellent. It can be easily formed with space efficiency.

  A third aspect of the present invention is the fluid-filled vibration isolator according to the second aspect, wherein the fluid-filled vibration isolator is located on the inner peripheral side of a circumscribed circle connecting the tips of the plurality of slits extending radially, The reinforcing portion in the elastic tongue piece is formed.

  In the fluid-filled vibration isolator of this aspect, each elastic tongue formed by a radial slit suppresses the adverse effect on the spring characteristics at the base end portion, and particularly each elasticity considered to be easily elastically deformed irregularly. An intermediate portion in the length direction of the tongue piece can be efficiently reinforced. Therefore, the effect of preventing cavitation noise due to deformation of each elastic tongue and opening the slit when a shocking large load is input, and the orifice passage and liquid by stabilizing the deformation of each elastic tongue. It is possible to realize both the vibration-proofing effect of the pressure absorbing mechanism and the higher level of both.

  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 reinforcing portion of the elastic tongue piece is directed toward both front and back sides of the elastic tongue piece. It is constituted by a protruding rubber protrusion.

  In the fluid-filled vibration isolator of this aspect, the elastic tongue piece has a reinforcing effect that is substantially the same on both the front and back sides, so that the elastic characteristics of the elastic tongue piece are stable, and the elastic tongue piece by the reinforcing portion The unstable deformation suppressing effect can be more effectively exhibited.

  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 reinforcing portion of the elastic tongue piece is a protrusion extending in a width direction of the elastic tongue piece. It is composed of articles.

  In the fluid-filled vibration isolator of this aspect, the unstable deformation of the elastic tongue is efficiently suppressed without greatly degrading the deformation characteristics of the elastic tongue for opening the slit when avoiding excessive pressure in the pressure receiving chamber. This is effective even when the width of the elastic tongue is large. For example, when each elastic tongue piece is formed in a fan plate shape by a plurality of radially extending slits, the reinforcing portion of each elastic tongue piece is formed by an annular ridge extending in the circumferential direction around the radial center of the slit. Can be formed. In addition, it is also possible to form a plurality of protrusions of this aspect at a predetermined distance in the length direction of the elastic tongue piece.

  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 hydraulic pressure absorbing rubber plate is harder than the hydraulic pressure absorbing rubber plate. A reinforcing plate is fixed, and a through-hole in the thickness direction is formed in the hard reinforcing plate, and the slit is provided in a portion of the hydraulic pressure absorbing rubber plate that covers the through-window, and the elastic plate A tongue piece is formed.

  In the fluid-filled vibration isolator of this aspect, the elastic deformation of the hydraulic pressure absorbing rubber plate itself is limited by the hard reinforcing plate, thereby preventing excessive deformation and irregular deformation of the hydraulic pressure absorbing rubber plate. Therefore, the adverse effect on the vibration isolation effect of the orifice passage due to the overall excessive deformation of the hydraulic pressure absorbing rubber plate is prevented, and the intended vibration isolation effect can be obtained more advantageously. Further, since the elastic tongue pieces are also provided with the reinforcing action of the hard reinforcing plate on the base end side, the stability of the deformation mode of the elastic tongue pieces can be further improved.

  According to a seventh aspect of the present invention, in the fluid-filled vibration isolator according to any one of the first to sixth aspects, a displacement in the thickness direction of the hydraulic pressure absorbing rubber plate is allowed and a displacement amount is limited. And the rubber plate support part which supports this hydraulic pressure absorption rubber plate is provided in said 2nd attachment member.

  In the fluid-filled vibration isolator of this aspect, the displacement amount of the hydraulic pressure absorbing rubber plate is surely limited, thereby preventing the orifice passage from being caused by the overall excessive deformation or excessive displacement of the hydraulic pressure absorbing rubber plate. An adverse effect on the vibration effect can be prevented. Specifically, for example, when the hydraulic pressure absorbing rubber plate is hard by including the hard reinforcing plate according to the sixth aspect, the outer peripheral portion of the hydraulic pressure absorbing rubber plate is predetermined on both sides in the plate thickness direction. The rubber plate support portion of this aspect can be realized by a concave annular groove that is supported with a gap of 5 mm. In the case of a hydraulically absorbing rubber plate that is not provided with such a hard reinforcing plate and can be elastically deformed, for example, a regulating plate having a plurality of through holes is provided on both sides in the thickness direction of the hydraulically absorbing rubber plate. The rubber plate support portion can be realized by disposing with a predetermined gap and limiting the amount of displacement by the contact of the hydraulic pressure absorbing rubber plate to both the restriction plates.

  In the fluid-filled vibration isolator having a structure according to the present invention, the irregular deformation of the elastic tongue piece is suppressed by the reinforcing portion at the time of normal vibration input, so that the orifice passage and the hydraulic pressure absorbing rubber plate The anti-vibration effect can be sufficiently secured. Moreover, when an excessive pressure fluctuation is induced in the pressure receiving chamber due to an input of a shocking heavy load, the elastic tongue piece elastically deforms and the pressure in the pressure receiving chamber is quickly eliminated through the slit, thereby causing cavitation, etc. This problem can be effectively prevented.

It is a longitudinal cross-sectional view which shows the fluid enclosure type vibration isolator as 1st embodiment of this invention, Comprising: II sectional drawing of FIG. The top view of the movable member which comprises the fluid enclosure type vibration isolator. The bottom view of the movable member. IV-IV sectional drawing of FIG. VV sectional drawing of FIG. The top view of the movable member as another form of this invention. The bottom view of the movable member. VIII-VIII sectional drawing of FIG.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 shows a fluid-filled vibration isolator 10 as a first embodiment according to the present invention. This fluid-filled vibration isolator 10 includes a first attachment member 12 attached to one member to be vibration-isolated and a second attachment member 14 attached to the other member to be anti-vibration connected. The elastic bodies 16 are elastically connected to each other. And, for example, the first mounting member 12 is attached to the power unit of the automobile which is one member to be vibration-proof connected, and the second mounting member 14 is attached to the body of the automobile which is the other member to be vibration-proof connected. As a result, the power unit is supported by the vehicle body in a vibration-proof manner. In the following description, the vertical direction means the vertical direction in FIG. 1 which is the main vibration input direction in principle.

  More specifically, the first mounting member 12 is a highly rigid member made of a metal material such as iron or aluminum alloy, and has a substantially circular block shape. Further, a flange portion 18 that extends outward in the radial direction is integrally formed at the upper end portion of the first mounting member 12. Further, a bolt hole 20 is formed so as to open on the upper end surface of the first mounting member 12 and extend on the central axis, and a female screw is engraved on the inner peripheral surface of the bolt hole 20. The first mounting member 12 is bolted to a power unit (not shown) by, for example, a mounting bolt (not shown) screwed into the bolt hole 20.

  On the other hand, the second mounting member 14 is a highly rigid member formed of the same metal material as the first mounting member 12, and has a thin cylindrical shape with a large diameter as a whole. In addition, a constricted portion 22 is provided at an intermediate portion in the axial direction of the second mounting member 14. The constricted portion 22 includes a tapered portion 24 that gradually decreases in diameter toward the lower side in the axial direction, and an annular stepped portion 26 that widens from the lower end portion of the tapered portion 24 toward the outer peripheral side. An annular step 28 that extends toward the outer peripheral side is formed at the lower end of the second mounting member 14, and an annular shaped caulking piece that extends downward on the outer peripheral edge of the step 28. 30 is integrally formed. Such a second mounting member 14 is fixed to the vehicle body, for example, by attaching a bracket (not shown) that is fitted and fixed to the second mounting member 14 to the vehicle body.

  The first mounting member 12 and the second mounting member 14 as described above are disposed on the same central axis, and the first mounting member 12 is spaced apart from the second mounting member 14 in the axial direction. Has been placed. The main rubber elastic body 16 is interposed between the first mounting member 12 and the second mounting member 14 so that the first mounting member 12 and the second mounting member 14 are the main rubber elastic body. 16 is elastically connected.

  The main rubber elastic body 16 is formed of a rubber elastic body having a thick, substantially truncated cone shape. Further, a large-diameter circular recess 32 is formed in the central portion in the radial direction of the main rubber elastic body 16 so as to open to the large-diameter side end surface (the lower end surface in FIG. 1). Further, the first mounting member 12 is inserted into the small diameter side end portion of the main rubber elastic body 16 so that the lower surface of the flange portion 18 is overlapped with the small diameter side axial end surface of the main rubber elastic body 16. And vulcanized. On the other hand, the upper portion of the second mounting member 14 and the taper portion 24 are overlapped and vulcanized and bonded to the outer peripheral surface of the large-diameter side end portion of the main rubber elastic body 16. Thereby, the first attachment member 12 and the second attachment member 14 are connected to each other by the main rubber elastic body 16. The main rubber elastic body 16 in the present embodiment is formed as an integrally vulcanized molded product that integrally includes the first mounting member 12 and the second mounting member 14.

  Further, a seal rubber layer 34 integrally formed with the main rubber elastic body 16 is fixed to the inner peripheral surface of the second mounting member 14. The seal rubber layer 34 is formed of a thin rubber film, and is formed so as to cover a portion extending from the inner peripheral surface of the step portion 26 to the inner peripheral portion of the step 28 in the second mounting member 14.

  A flexible film 36 is disposed at the lower end opening of the second mounting member 14. The flexible film 36 is formed of a rubber film having a thin, large-diameter, generally circular dome shape, so that elastic deformation is easily allowed. A fixing metal fitting 38 is fixed to the outer peripheral edge of the flexible film 36. The fixing bracket 38 has a substantially annular shape, and is integrally provided with a cylindrical fixing portion 40 and a hook-like portion 42 that extends from the upper end of the fixing portion 40 toward the outer peripheral side. Then, the outer peripheral edge of the flexible membrane 36 is vulcanized and bonded to the fixing portion 40 of the fixing bracket 38, so that the flexible membrane 36 is integrally provided with the fixing bracket 38. It is formed as. In the present embodiment, the fixing fitting 38 is covered with a rubber layer integrally formed with the flexible film 36 over substantially the entire surface excluding the outer peripheral edge and the upper end surface of the bowl-shaped portion 42.

  Such a flexible membrane 36 is assembled to the second attachment member 14. That is, the outer peripheral edge portion of the hook-shaped portion 42 of the fixing bracket 38 is superimposed on the step 28 provided at the lower end portion of the second mounting member 14 from below, and the hook-shaped portion 42 is attached to the second mounting member 14. The flexible membrane 36 is fixed to the lower end portion of the second attachment member 14 by being caulked and fixed by the caulking piece 30 formed integrally with the member 14.

  As described above, the flexible film 36 is assembled to the integrally vulcanized molded product of the main rubber elastic body 16 including the first mounting member 12 and the second mounting member 14, thereby the second mounting member. 14 is closed fluid-tightly by the main rubber elastic body 16, and the axially lower opening of the second mounting member 14 is fluid-tightly closed by the flexible membrane 36. ing. Thereby, a fluid sealing region 44 as a fluid chamber sealed from the outside is formed between the main rubber elastic body 16 and the flexible film 36 on the inner peripheral side of the second mounting member 14. .

  In addition, in the fluid sealing region 44, incompressible fluid such as water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixed solution thereof is sealed as a sealing fluid. The sealed fluid is not particularly limited, but the viscosity is 0.1 Pa · s or less in order to advantageously obtain a vibration isolating effect based on the resonance action of the fluid flowing in the orifice passage 68 described later. It is desirable to employ a low viscosity fluid. In addition, such fluid sealing does not attach the flexible membrane 36 to the second mounting member 14 (an integral vulcanization molded product of the main rubber elastic body 16 provided with the second mounting member 14). By carrying out in a compressible fluid, it can be advantageously realized.

  A partition member 46 is accommodated in the fluid sealing area 44. The partition member 46 has a thick, substantially disk shape, and is configured to include a partition member main body 48 and a lid member 50 in the present embodiment.

  The partition member body 48 as a whole has a thick, substantially disk shape, and is formed of a hard material such as iron, an aluminum alloy, or a hard synthetic resin material in the present embodiment. In addition, a notch-shaped groove 52 that opens to the upper end surface and the outer peripheral surface is formed in the outer peripheral edge of the partition member main body 48 so as to extend in the circumferential direction with a predetermined length shorter than one round.

  In addition, an accommodation recess 54 is formed in the central portion of the partition member body 48 in the radial direction. The accommodation recess 54 is formed in the partition member main body 48 at a predetermined distance on the inner peripheral side of the notch-shaped groove 52, and is a circular recess that opens upward. Further, a lower central recess 56 is formed in the central portion of the partition member body 48 in the radial direction. The lower central recess 56 is a circular recess formed in the partition member main body 48 at a position substantially corresponding to the housing recess 54 in the vertical direction, and is opened downward in the axial direction.

  On the other hand, the lid member 50 has a thin disk shape having substantially the same diameter as the partition member main body 48, and is formed of the same hard material as the partition member main body 48 in the present embodiment. And the partition member 46 in this embodiment is comprised by overlapping and combining the cover member 50 with respect to the upper end surface of the partition member main body 48 from upper direction.

  As described above, the lid member 50 is overlapped with the partition member main body 48, so that the upper opening of the notch-shaped groove 52 is covered with the lid member 50 and opens to the outer peripheral surface of the partition member 46 in the circumferential direction. A circumferential groove extending in the direction is formed using the notched groove 52. Further, the opening portion of the housing recess 54 formed in the partition member main body 48 is covered with the lid member 50, so that a housing region 58 is formed inside the partition member 46.

  Such a partition member 46 is disposed in the fluid sealing region 44 in a housed state. That is, the partition member 46 is inserted from the lower opening of the second mounting member 14, and the outer peripheral edge of the lid member 50 is brought into contact with the stepped portion 26 of the second mounting member 14 from below. At the same time, the hook-shaped portion 42 of the fixing bracket 38 is superimposed on the outer peripheral edge of the partition member main body 48 from below. Then, when the hook-shaped portion 42 of the fixing bracket 38 is fixed to the second mounting member 14 by the caulking piece 30 of the second mounting member 14, the partition member 46 becomes the stepped portion of the second mounting member 14. 26 and the hook-like portion 42 of the fixing bracket 38, and fixedly supported by the second mounting member 14. In this embodiment, the partition member 46 is inserted into the second mounting member 14 and subjected to a diameter reduction process such as an eight-way drawing on the second mounting member 14. The outer peripheral surface is brought into close contact with the second mounting member 14 via the seal rubber layer 34.

  In this way, the partition member 46 is disposed so as to extend in the direction perpendicular to the axis in the fluid sealing region 44 and is supported by the second mounting member 14, so that the fluid sealing region 44 has a shaft with the partition member 46 interposed therebetween. The direction is divided into upper and lower sides. That is, on one side (upper side) sandwiching the partition member 46, a part of the wall portion is constituted by the main rubber elastic body 16, and a pressure receiving chamber 60 is formed in which pressure fluctuation is caused when vibration is input. On the other side (lower side) across the partition member 46, a part of the wall portion is formed of the flexible film 36, and an equilibrium chamber 62 in which volume change is allowed by deformation of the flexible film 36 is formed. Has been. The pressure receiving chamber 60 and the equilibrium chamber 62 are filled with the incompressible fluid sealed in the fluid sealing region 44.

  Moreover, the outer peripheral side opening part of the said circumferential groove formed in the outer peripheral part of the partition member 46 is covered fluid-tightly by the 2nd attachment member 14, and the outer peripheral part of the partition member 46 is made into the circumferential direction. A tunnel-shaped passage extending in a predetermined length is formed. Further, the lid member 50 is formed with an upper communication passage 64 that opens one end of the tunnel-shaped passage above the partition member 46, and the partition member body 48 has the other end of the tunnel-shaped passage. A lower communication passage 66 is formed to open the end of the lower portion below the partition member 46. One end of the tunnel-shaped passage communicates with the pressure receiving chamber 60 through the upper communication passage 64, and the other end of the tunnel-shaped passage communicates with the equilibrium chamber 62 through the lower communication passage 66. An orifice passage 68 that communicates the pressure receiving chamber 60 and the equilibrium chamber 62 with each other is formed. In the present embodiment, the ratio between the passage length of the orifice passage 68 and the passage sectional area is appropriately set according to the rigidity of the wall spring of the pressure receiving chamber 60, so that the two chambers 60, 62 are connected through the orifice passage 68. The resonance frequency of the fluid to be flowed is tuned to a low frequency of about 10 Hz corresponding to an engine shake of an automobile.

  Here, a movable member 70 as shown in FIGS. 2 to 5 is accommodated in the accommodating region 58 formed in the partition member 46. The movable member 70 has a substantially disc shape as a whole, and is constituted by a hydraulic pressure absorbing rubber plate 72 and a hard reinforcing plate 74 as a restraining plate.

  The hydraulic pressure absorbing rubber plate 72 is a rubber elastic body having a substantially disc shape, and the outer diameter dimension thereof is slightly smaller than the inner diameter dimension of the accommodation region 58. Further, the thickness of the hydraulic pressure absorbing rubber plate 72 is also slightly smaller than the height of the accommodating area 58, and the upper and lower surfaces of the hydraulic absorbing rubber plate 72 are accommodated while being disposed in the accommodating area 58. Due to the gap existing between the upper and lower inner surfaces of the region 58, the displacement of the hydraulic pressure absorbing rubber plate 72 in the housing region 58 in the thickness direction is allowed. On the outer peripheral surface of the hydraulic pressure absorbing rubber plate 72, positioning protrusions 76 that protrude with a lip shape extending in the circumferential direction are integrally formed at a plurality of locations on the circumference. The plurality of positioning protrusions 76 position the hydraulic pressure absorbing rubber plate 72 at the approximate center within the accommodation region 58, and displacement in the plate thickness direction is allowed with a small contact resistance.

  Furthermore, a substantially disc-shaped hard reinforcing plate 74 is disposed in a state of being embedded in the middle portion in the thickness direction of the hydraulic pressure absorbing rubber plate 72 and is vulcanized and bonded to the hydraulic pressure absorbing rubber plate 72. . The hard reinforcing plate 74 is formed of a synthetic resin material, a metal material, or the like having a rigidity higher than that of the hydraulic pressure absorbing rubber plate 72. The outer diameter of the hard reinforcing plate 74 is smaller than the outer diameter of the hydraulic pressure absorbing rubber plate 72, and the elastic deformation of the central portion of the hydraulic absorbing rubber plate 72 is substantially caused by the hard reinforcing plate 74. It is blocked.

  In this embodiment, the upper and lower elastic contact portions 78 and 78 projecting on both sides in the plate thickness direction at the outer peripheral edge portion of the hydraulic pressure absorbing rubber plate 72 positioned away from the outer peripheral side of the hard reinforcing plate 74 are It is integrally formed in an annular shape continuous in the direction. The protrusion height of the upper and lower elastic contact portions 78, 78 is continuously changed in the circumferential direction, so that the outer peripheral edge portion of the hydraulic pressure absorbing rubber plate 72 is on both sides in the plate thickness direction in the circumferential direction. It is made into the wavy part extended like a wave. That is, the outer peripheral edge of the hydraulic pressure absorbing rubber plate 72 does not substantially change the dimension in the thickness direction including the upper and lower elastic contact portions 78, 78, and the center position in the thickness direction is vertically changed in the circumferential direction. It has been changed to swing. In particular, in the present embodiment, the projecting tip surfaces of the upper and lower elastic contact portions 78, 78 have a shape that is smoothly waved in the circumferential direction at a constant cycle (for example, a cycle of 90 degrees in the circumferential direction) in a substantially sine wave shape. .

  The hard reinforcing plate 74 is formed with a plurality of through windows 80 penetrating in the plate thickness direction. In the present embodiment, each through window 80 is formed as a circular hole, and four through windows 80 are formed at equal intervals in the circumferential direction at the radial intermediate portion of the hydraulic pressure absorbing rubber plate 72. Each through window 80 is covered with a rubber valve plate 82 made of a single hydraulic pressure absorbing rubber plate 72.

  The rubber valve plate 82 has a disk shape that expands with a substantially constant thickness. On the outer peripheral portion of the rubber valve plate 82, buffer ribs 84 that are located on the inner peripheral edge portion of the through window 80 of the hard reinforcing plate 74 and project on both sides in the thickness direction are integrally formed in an annular shape over the entire circumference. . The protruding height of the buffer rib 84 is set so as to protrude most outward in the thickness direction on the entire surface of the hydraulic pressure absorbing rubber plate 72. In the outer peripheral portion of each rubber valve plate 82, buffer ribs 84, 84 projecting from the upper and lower surfaces of the hydraulic pressure absorbing rubber plate 72 are formed, whereby the outer peripheral portion of the rubber valve plate 82 is reinforced and liquid The impact at the time of contact with the inner surface of the accommodation area 58 of the pressure absorbing rubber plate 72 is reduced.

  Further, a slit 86 is formed in the rubber valve plate 82. A plurality of slits 86 are formed so as to extend radially outward from the center of the rubber valve plate 82 and penetrate the rubber valve plate 82 in the thickness direction. In the present embodiment, as shown in FIGS. 2 and 3, three slits 86 are formed at equal intervals around the radiation center, and between the adjacent slits 86, 86 in the circumferential direction, a sector shape is formed. Elastic tongue pieces 88 each having a flat plate shape are formed. That is, in the elastic tongue 88, the radial center point of the plurality of slits 86, 86, 86 is the tip of the elastic tongue 88, and the slits on both sides of the elastic tongue 88 are centered on the radial center point. A portion located on a line of an arc extending by connecting the tips of 86 and 86 is a base end portion of the elastic tongue 88.

  Each slit 86 has a length that does not reach the outer peripheral edge of the rubber valve plate 82. In particular, in this embodiment, the length of the tip that does not reach the elastic contact portions 78 and 78 slightly. Each slit 86 is formed. Each slit 86 is closed in an initial state where no external force is applied, and both end surfaces in the circumferential direction of each rubber valve plate 82 are in the circumferential end surfaces of the rubber valve plates 82 adjacent to each other across the slit 86. On the other hand, the slits 86 are closely overlapped over the entire length. However, the slit 86 does not need to be completely closed according to the required vibration isolation characteristics, and the circumferential end surfaces of the elastic tongue pieces 88 adjacent in the circumferential direction may be slightly separated from each other. .

  Further, each elastic tongue 88 is integrally formed with a reinforcing portion 90 that is a partially thick rubber protrusion. The reinforcing portion 90 in the elastic tongue 88 is constituted by a protrusion that extends in the width direction of the elastic tongue 88. The width direction of the elastic tongue piece 88 is a direction orthogonal to the length direction extending from the base end portion of the elastic tongue piece 88 to the distal end portion, and is also a direction extending orthogonally to the slit 86. In the present embodiment, the reinforcing portion 90 is formed in each elastic tongue 88 with an arc shape extending in the circumferential direction of a circle centered on the radial center of the slit 86. Further, in the present embodiment, the reinforcing portion 90 is formed in a region surrounded by a circumscribed circle connecting the tips of the radially extending slits 86 in the elastic tongue 88. Further, it is desirable that the reinforcing portion 90 is formed at an intermediate portion in the length direction from the base end portion to the tip end portion of the elastic tongue 88, and is particularly biased to the outer peripheral side from the center in the length direction. Specifically, on both the front and back surfaces of the rubber valve plate 82, elastic ridges extending continuously in the circumferential direction around the radial center of the radially extending slit 86 and having a mountain-shaped cross section are formed. By being divided, an independent reinforcing portion 90 is formed for each elastic tongue 88.

  In addition, it is preferable that the reinforcement parts 90 and 90 formed in the front and back both surfaces of each elastic tongue piece 88 are the same size and the same size mutually, and are formed symmetrically. Thereby, the shape of the elastic tongue 88 is stabilized, and the elastic deformation effect can be sufficiently exhibited. Further, in this embodiment, in the cross section of the reinforcing portion 90, the top portion is biased toward the outer peripheral side, and the curvature radius on the inner peripheral side is made larger than the curvature radius on the outer peripheral side of the reinforcing portion 90, and is gentle. It is inclined to. Thus, in the elastic tongue 88, the distal end portion located on the center side of the rubber valve plate 82 has a smaller width in the circumferential direction than the proximal end portion located on the outer peripheral side of the rubber valve plate 82, and is easily deformed. In consideration of the above characteristics, the characteristic change exerted on the rubber valve plate 82 by the formation of the reinforcing portions 90, 90 is reduced. Further, it is desirable that the protruding height dimension of the reinforcing portion 90 is 30 to 100% of the thickness dimension of the elastic tongue 88. This is because if the reinforcing portion 90 is too small, it is difficult to obtain a sufficient reinforcing effect, and if it is too large, there is a concern about adverse effects on the elastic characteristics of the elastic tongue 88 and the like.

  The movable member 70 having such a structure is disposed in an accommodation region 58 formed inside the partition member 46, and the movable member 70 is arranged in the thickness direction in the accommodation region 58 as described above. It can be displaced by a predetermined distance. Further, an upper through hole 96 penetrating in the axial direction is formed in the central portion of the lid member 50 constituting the upper side wall portion of the containing area 58, and the containing area 58 communicates with the pressure receiving chamber 60 through the upper through hole 96. Has been. On the other hand, a lower through hole 98 penetrating in the axial direction is formed in the central portion of the partition member main body 48 (the bottom wall portion of the housing recess 54) constituting the lower wall portion of the housing area 58, and the lower side The accommodation region 58 communicates with the equilibrium chamber 62 through the through hole 98.

  In the present embodiment, the upper and lower through holes 96 and 98 are both large-diameter circular holes, and the upper and lower through holes 96 and 98 are formed with substantially the same diameter. The inner diameter of the upper and lower through holes 96 and 98 is smaller than the outer diameter of the hard reinforcing plate 74 in the movable member 70, and the region where the hard reinforcing plate 74 is disposed in the movable member 70 is the upper and lower through holes. The amount of displacement of the movable member 70 in the plate thickness direction is reliably defined by contacting the outer peripheral portions 96 and 98.

  In short, by forming the upper and lower through holes 96, 98, the partition member 46 is formed with an annular groove that opens to the inner peripheral surface and extends in the circumferential direction. The outer peripheral part of 70 is inserted. Since the movable member 70 is supported by the second mounting member 14 via the partition member 46 so as to be displaceable in a region where the amount of displacement is limited by contact with the inner surface of the annular groove. is there. As is clear from this, in this embodiment, the partition member 46 constitutes a rubber plate support portion that supports the hydraulic pressure absorbing rubber plate 72 so as to be displaceable.

  Furthermore, the size of the upper and lower through holes 96 and 98 is such that the rubber valve plate 82 provided in the movable member 70 is exposed to the pressure receiving chamber 60 and the equilibrium chamber 62 through the upper and lower through holes 96 and 98 in a sufficient area. Is set to be. Specifically, 50% or more, preferably 80% or more of each rubber valve plate 82 in the axial projection is preferably exposed to the pressure receiving chamber 60 and the equilibrium chamber 62 through the upper and lower through holes 96 and 98. .

  Thereby, the pressure of the pressure receiving chamber 60 is applied to the upper surface of the movable member 70 disposed in the accommodating region 58 through the upper through hole 96 and the equilibrium chamber is applied to the lower surface of the movable member 70. A pressure of 62 is applied through the lower through hole 98.

  Since the movable member 70 is disposed in the accommodating region 58 so as to partition the pressure receiving chamber 60 and the equilibrium chamber 62, a relative pressure difference is generated between the pressure receiving chamber 60 and the equilibrium chamber 62 due to vibration input. Then, the movable member 70 is slightly displaced in the axial direction to constitute a hydraulic pressure absorbing mechanism that absorbs pressure fluctuations in the pressure receiving chamber 60.

  In the present embodiment, the outer peripheral edge of the hydraulic pressure absorbing rubber plate 72 extends to the outer peripheral side with respect to the upper and lower through holes 96 and 98, and the rigid reinforcing plate 74 to which the hydraulic pressure absorbing rubber plate 72 is fixed. Is formed in a disk shape having a larger diameter than the opening regions of the upper and lower through holes 96 and 98, and the outer peripheral edge of the hard reinforcing plate 74 is located on the outer peripheral side of the upper and lower through holes 96 and 98 over the entire circumference. It has spread. As a result, when a large amplitude vibration is input, the outer peripheral portion of the hydraulic pressure absorbing rubber plate 72 to which the hard reinforcing plate 74 is fixed is brought into contact with the upper and lower inner surfaces of the accommodation region 58, so that the axial direction of the movable member 70 is reached. The displacement at is more reliably limited.

  In addition, when the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 is extremely large, the slit 86 is opened by elastic deformation of the elastic tongue 88 formed on the rubber valve plate 82, and the slit 86 passes through the slit 86. The pressure receiving chamber 60 and the equilibrium chamber 62 are communicated with each other. As a result, a short-circuit mechanism is configured to allow the pressure receiving chamber 60 and the equilibrium chamber 62 to communicate with each other with a smaller flow resistance than that of the orifice passage 68 when a shocking large load is input. In short, in the present embodiment, the short-circuit mechanism is realized by a valve structure that switches between the communication state and the cutoff state of the slit 86 by using the elasticity of the elastic tongue 88.

  In the fluid-filled vibration isolator 10 having such a structure, when low-frequency large-amplitude vibration corresponding to an engine shake of an automobile is input while being mounted on a vehicle, the pressure receiving chamber 60 and the equilibrium chamber 62 are relative to each other. Based on the pressure fluctuation, fluid flow is generated through the orifice passage 68 tuned to the low frequency range. At this time, since the relative pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 exceeds the hydraulic pressure absorbing function due to the displacement of the movable member 70, the displacement amount of the movable member 70 is limited and substantially restrained. Therefore, the amount of fluid flow through the orifice passage 68 is effectively ensured, and the vibration isolation effect (high damping effect) based on the fluid action such as the resonance action of the fluid can be effectively exhibited.

  In addition, when a low-frequency large-amplitude vibration corresponding to a normal engine shake is input, the pressure fluctuation in the pressure receiving chamber 60 is released to the equilibrium chamber 62 by the fluid flow through the orifice passage 68, and the pressure fluctuation in the pressure receiving chamber 60 is remarkably increased. It won't grow. Therefore, also in the movable member 70, the slit 86 is held in a closed state against the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 due to the elasticity of the elastic tongue 88. Therefore, escape of the pressure in the pressure receiving chamber 60 through the slit 86 is prevented, the fluid flow through the orifice passage 68 based on the relative pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62, and the vibration isolation performance based on the fluid flow. Can be more effectively exhibited.

  In addition, when a small amplitude vibration in the middle to high frequency range corresponding to idling vibration or traveling noise is input, the orifice passage 68 is substantially cut off due to anti-resonant action. At this time, the movable member 70 is allowed to be slightly displaced in the plate thickness direction based on the relative pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62, so that the pressure fluctuation induced in the pressure receiving chamber 60 is reduced to the equilibrium chamber 62 side. The hydraulic pressure absorbing action that is absorbed and absorbed is exhibited. Therefore, a significant increase in the dynamic spring associated with the substantial blocking of the orifice passage 68 is avoided, and a good vibration isolation performance is exhibited. It should be noted that, even in the middle to high frequency range corresponding to idling vibration or traveling noise, the pressure variation in the pressure receiving chamber 60 is released to the equilibrium chamber 62 based on the displacement of the movable member 70, so that the slit 86 is formed. It is maintained in a substantially closed state.

  On the other hand, when a shocking large load is input due to overcoming a step during traveling and the like, a significant pressure fluctuation occurs in the pressure receiving chamber 60, each of the rubber valve plates 82 in the rubber valve plate 82 is based on the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62. The elastic tongue 88 is greatly deformed, and the slit 86 is opened. Then, the pressure receiving chamber 60 and the equilibrium chamber 62 are communicated with each other through the slit 86, and by the fluid flow through the slit 86, extremely significant pressure fluctuations in the pressure receiving chamber 60 can be eliminated as quickly as possible. Therefore, for example, the generation of cavitation in the pressure receiving chamber 60 can be suppressed, and the generation of abnormal noise and vibration due to cavitation can be prevented.

  Here, the elastic tongue piece 88 in the rubber valve plate 82 is partially thickened to form a reinforcing portion 90. As a result, the elastic tongue piece 88 is elastically deformed to secure the characteristic of opening the slit 86, and the local deformation rigidity of the elastic tongue piece 88 is enhanced to stabilize the deformation of the elastic tongue piece 88. Yes. Therefore, when a shocking heavy load is input, the slit 86 can be opened to suppress significant pressure fluctuations in the pressure receiving chamber 60, and the orifice passage 68 such as engine shake, idling vibration, traveling booming noise, and the like can be absorbed. At the time of normal vibration input in which the anti-vibration effect is exhibited by the mechanism, irregular deformation of the elastic tongue 88 and unexpected opening of the slit 86 due to it are effectively prevented, and the orifice passage 68 and the hydraulic pressure absorbing mechanism are effectively prevented. Therefore, the desired vibration-proofing effect can be effectively exhibited.

  In particular, since the reinforcing portion 90 of the elastic tongue 88 is provided at an intermediate portion in the length direction of the elastic tongue 88, the elastic deformation characteristics at the base end portion of the elastic tongue 88 due to the formation of the reinforcing portion 90. And problems associated with an increase in mass at the tip of the elastic tongue 88 can be avoided. Therefore, by forming the reinforcing portion 90 as described above in the elastic tongue 88, while sufficiently ensuring the characteristics such as cavitation prevention exhibited based on the opening of the slit 86 at the time of shocking heavy load input, This makes it possible to effectively prevent the vibration-proof performance from deteriorating due to irregular deformation or resonance of the elastic tongue 88 during normal running or the like.

  Further, in this embodiment, the movable member 70 in which the hard reinforcing plate 74 is fixed to the hydraulic pressure absorbing rubber plate 72 formed of a rubber elastic body is employed, and the rubber valve plate 82 is surrounded by the hard reinforcing plate 74. It is reinforced. Since the reinforcing effect by the hard reinforcing plate 74 is also exerted on each elastic tongue 88, the deformation of the elastic tongue 88 can be further stabilized.

  Furthermore, in this embodiment, since the outer peripheral side of the rubber valve plate 82 is reinforced by the upper and lower buffer ribs 84, 84, cracks at the tip portion of the slit 86 are prevented, and excellent durability can be realized. Even if a crack occurs in the tip portion of the slit 86, the growth of the crack can be prevented by the hard reinforcing plate 74 disposed on the outer peripheral side of the rubber valve plate 82.

  As mentioned above, although embodiment of this invention has been described, this invention is not interpreted limitedly by the specific description in this embodiment.

  For example, in the above-described embodiment, the radial slit 86 configured by linear notches extending in three directions is illustrated, but the specific shape of the slit 86 is not particularly limited. Specifically, for example, the elastic tongue piece can be formed by a single slit curved in a U-shape as described in Patent Document 1, or a plurality of slits that are separated from each other. It is.

  Further, the reinforcing portion 90 formed on the elastic tongue 88 may be formed only on one of the upper surface and the lower surface, and by adopting mutually different sizes and shapes, the upward deformation characteristics and the downward direction. It is also possible to make the deformation characteristics different from each other. Furthermore, the reinforcing portion 90 does not have to be formed over the entire length of the elastic tongue 88 in the circumferential direction as in the above-described embodiment. For example, as shown in FIGS. It is also possible to configure the reinforcing portion by one or a plurality of independent elastic protrusions 100 in the piece 88. 6 to 8, in order to facilitate understanding, members and parts having the same structure as in the above embodiment are denoted by the same reference numerals as those in the above embodiment.

  In the embodiment, the plurality of through windows 80 are formed in the hard reinforcing plate 74 constituting the movable member 70, but a structure in which only one through window 80 is formed may be used. Further, the hard reinforcing plate 74 is not essential in the present invention, and the movable member 70 can be constituted by a single unit of the hydraulic pressure absorbing rubber plate 72 to which the hard reinforcing plate 74 is not fixed.

  Moreover, in the said embodiment, the movable member 70 comprised by the hydraulic pressure absorption rubber plate 72 is comprised by the component independent from the partition member 46, and is supported by the partition member 46 so that a micro displacement is possible in a plate | board thickness direction. However, the outer peripheral portion of the movable member 70 constituted by the hydraulic pressure absorbing rubber plate 72 can be fixedly supported by vulcanizing and adhering to the partitioning member 46 or holding it under pressure. is there. Thus, in the movable membrane structure in which the outer peripheral edge of the hydraulic pressure absorbing rubber plate 72 is fixedly supported by the partition member, the hydraulic pressure absorbing function can be exhibited based on the elastic deformation of the hydraulic pressure absorbing rubber plate 72.

  In addition, the elastic contact portion 78 and the buffer rib 84 that reduce the contact impact on the partition member 46 in the hydraulic pressure absorbing rubber plate 72 are provided as necessary. It is not limited. For example, in the above embodiment, the buffer ribs 84, 84 are formed on the outer peripheral portion of the rubber valve plate 82, but in addition to or instead of them, rubber protrusions and rubber protrusions protruding from the surface of the hard reinforcing plate 74, You may provide the buffer protrusion which consists of embossing etc.

  In the above embodiment, the upper and lower through holes 96 and 98 having large diameters are formed in the partition member 46, so that the front and back surfaces of the elastic tongues 88 formed in the movable member 70 are directly connected to the pressure receiving chamber 60 and the equilibrium. Although exposed to the chamber 62, for example, a plurality of small-diameter holes are formed instead of the large-diameter upper and lower through holes 96 and 98, and the pressure in the pressure receiving chamber 60 and the equilibrium chamber 62 is reduced through these small-diameter holes. It may be applied to each elastic tongue 88.

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

10: fluid-filled vibration isolator, 12: first mounting member, 14: second mounting member, 16: main rubber elastic body, 36: flexible membrane, 60: pressure receiving chamber, 62: equilibrium chamber, 68 : Orifice passage, 72: Hydraulic pressure absorbing rubber plate, 74: Hard reinforcing plate, 80: Through window, 86: Slit, 88: Elastic tongue piece, 90: Reinforcing part

  The present invention relates to a fluid-filled vibration damping device that is used, for example, in an engine mount or a suspension mount of an automobile and exhibits a vibration-proofing effect based on a fluid action of a fluid sealed inside.

  Conventionally, as a type of vibration isolator, the first mounting member and the second mounting member are connected by a rubber elastic body, and an incompressible fluid is sealed inside to provide a fluid action such as a resonance action of the fluid. 2. Description of the Related Art A fluid-filled vibration isolator that obtains a vibration isolating effect is known. Specific examples include those described in Japanese Patent No. 2805305 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2009-275910 (Patent Document 2). These fluid-filled vibration damping devices have a pressure receiving chamber in which a part of the wall portion is configured with a main rubber elastic body, and an equilibrium chamber in which a portion of the wall portion is configured with a flexible film, An incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and both chambers are connected to each other by an orifice passage. Then, at the time of vibration input between the first mounting member and the second mounting member, the fluid that is caused to flow in the orifice passage based on the relative pressure fluctuation caused between the pressure receiving chamber and the equilibrium chamber. The anti-vibration effect is exhibited based on the fluid action.

  By the way, the orifice passage can exhibit an effective anti-vibration effect in the frequency range tuned in advance, but the flow resistance becomes particularly large when vibration is input in a higher frequency range than the tuning frequency. Degradation tends to be a problem.

  Therefore, as shown in Patent Documents 1 and 2, there has been proposed a hydraulic pressure absorption mechanism that absorbs pressure fluctuations in the pressure receiving chamber when a high-frequency small-amplitude vibration is input that deviates from the tuning frequency of the orifice passage. Such a hydraulic pressure absorbing mechanism is constituted by a hydraulic pressure absorbing rubber plate disposed between the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber that are exerted on one surface of the hydraulic pressure absorbing rubber plate. When the hydraulic pressure absorbing rubber plate is displaced or deformed based on the pressure difference, small pressure fluctuations in the pressure receiving chamber are absorbed.

  In addition, the hydraulic pressure absorbing rubber plate that constitutes the hydraulic pressure absorbing mechanism is used for the purpose of eliminating sudden pressure fluctuations in the pressure receiving chamber when shocking heavy load is input and preventing abnormal noise caused by cavitation. An elastic tongue is formed by providing a slit penetrating in the plate thickness direction. This elastic tongue piece keeps the slit closed due to the elasticity of the hydraulic pressure absorbing rubber plate, and the elastic tongue piece receives the pressure only when a sudden pressure fluctuation is induced in the pressure receiving chamber by a shocking large load input. Excessive pressure fluctuation in the pressure receiving chamber is avoided by elastically deforming the chamber side or the equilibrium chamber side and opening the slit.

  However, when the present inventor has examined such a fluid-filled vibration isolator having a conventional structure, a normal input that requires an anti-vibration effect or the like by an orifice passage accompanying the provision of a slit in the hydraulic pressure absorbing rubber plate. It has been found that there is a possibility of adversely affecting the vibration isolation performance against vibration. That is, a large pressure fluctuation is not caused in the pressure receiving chamber, and a slit is provided in the hydraulic pressure absorbing rubber plate even at the time of vibration input that only causes the pressure fluctuation of the pressure receiving chamber to such an extent that the slit is originally kept closed. In some cases, the vibration-proof performance is reduced due to the above.

Japanese Patent No. 2805305 JP 2009-275910 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is that a slit is formed in the hydraulic pressure absorbing rubber plate in order to avoid excessive pressure fluctuation in the pressure receiving chamber. An object of the present invention is to provide a novel structure in which an adverse effect on vibration proof performance against normal input vibration is suppressed in a fluid-filled vibration proof device provided with an elastic tongue piece.

A first aspect of the present invention made to solve such a problem is that the first mounting member and the second mounting member are connected by the main rubber elastic body, and the wall portion is formed by the main rubber elastic body. A pressure receiving chamber in which a part of the pressure receiving chamber is formed, and an equilibrium chamber in which a part of the wall portion is formed of a flexible film are formed, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, In the fluid filled type vibration damping device in which the pressure receiving chamber and the equilibrium chamber are communicated with each other by an orifice passage, a hydraulic pressure absorbing rubber plate is disposed between the pressure receiving chamber and the equilibrium chamber. The pressure of the pressure receiving chamber is exerted on one surface of the pressure absorbing rubber plate, and the pressure of the equilibrium chamber is exerted on the other surface of the hydraulic pressure absorbing rubber plate. Absorbs pressure fluctuation in the pressure receiving chamber based on displacement and deformation of the hydraulic pressure absorbing rubber plate based on the difference That while hydraulic absorbing mechanism is configured, the liquid pressure absorption rubber plate is formed elastic tongues by slits, receiving chamber and said equilibrium the slit is opened by the elastic deformation of the elastic tongue piece A short-circuit mechanism for short-circuiting the chamber, and a thick reinforcing portion is integrally formed at the intermediate portion in the length direction from the base end portion to the tip end portion of the elastic tongue piece , and the hydraulic pressure The absorbent rubber plate is provided with a plurality of radially extending slits, and the elastic tongue pieces are formed in the circumferential direction between the adjacent slits around the radial center of the slits. The reinforcing portion of the elastic tongue piece is formed on the inner peripheral side of a circumscribed circle connecting the tips of the plurality of radially extending slits, and the reinforcing portion of the elastic tongue piece is Elastic tongue width direction Characterized in that it is constituted by ridges extending over the entire length.

  In the fluid-filled vibration isolator having the structure according to this aspect, a vibration isolating effect based on the resonance action of the fluid flowing through the orifice passage is exhibited with respect to the low frequency large amplitude vibration in which the orifice passage is tuned. In addition, for high-frequency, small-amplitude vibrations, the pressure absorbing function of the pressure receiving chamber based on the displacement and deformation of the hydraulic pressure absorbing rubber plate is exerted, so that a significant high dynamic spring due to substantial closure of the orifice passage is avoided. As a result, a good vibration isolation effect can be obtained. Furthermore, for the input of a shocking heavy load, the elastic tongue formed on the hydraulic pressure absorbing rubber plate is elastically deformed to open the slit, so that the pressure receiving chamber side partitioned by the hydraulic pressure absorbing rubber plate And the equilibrium chamber side are in communication. As a result, a large pressure such as a negative pressure in the pressure receiving chamber is eliminated as quickly as possible, and for example, it is possible to reduce or avoid the generation of abnormal noise and vibration caused by cavitation.

  In addition, in the fluid-filled vibration isolator of this aspect, the elastic tongue piece of the hydraulic pressure absorbing rubber plate is partially thickened to form the reinforcing portion, so that the hydraulic pressure absorbing rubber plate and the elastic tongue are formed. While avoiding a large influence on the overall spring characteristics of the piece, minute elastic deformation or irregular elastic deformation in the elastic tongue piece can be suppressed. As a result, the spring constant is made relatively small at the slit during normal vibration input that requires vibration-proofing effect due to fluid flow through the orifice passage and vibration-proofing effect due to displacement and deformation of the hydraulic pressure absorbing rubber plate. Irregular vibration, minute deformation, or resonance deformation of the tongue piece is suppressed, and the shape of the elastic tongue piece, that is, the entire hydraulic pressure absorbing rubber plate is stabilized. As a result, under normal vibration input conditions where rapid absorption of the pressure in the pressure receiving chamber is not required, adverse effects on vibration isolation performance due to the provision of slits and elastic tongues are suppressed, and the desired vibration isolation effect is achieved. It can be demonstrated effectively.

  That is, as a result of investigation by the present inventor, the elastic tongue formed on the hydraulic pressure absorbing rubber plate may be elastically deformed under specific conditions such as its spring characteristics and the frequency of input vibration, and the shape may become unstable. It was found that there is a possibility that the anti-vibration property may be adversely affected by the elastic tongue piece being deformed in an unstable manner. Based on this knowledge, the present invention has been completed, and in the present invention, stabilization of vibration isolation characteristics can be achieved by suppressing unstable deformation that is not desired in the elastic tongue piece.

  Specifically, instability deformation and minute repetitive deformation such as resonance, which are problems in the elastic tongue, are especially reinforced by reinforcing the middle part in the length direction of the elastic tongue, so that the slit at the time of heavy load input It has been found that the liquid pressure can be effectively suppressed without impairing the action of eliminating the hydraulic pressure. The base end of the elastic tongue is supported by a hydraulic pressure absorbing rubber plate to prevent unstable deformation, and it is necessary to further increase the spring rigidity by providing a reinforcing part on the base end. In addition to being poor, there is a possibility that the deformation resistance to the slit opening operation due to the deformation of the elastic tongue piece becomes too large, which may hinder the slit opening operation. In addition, if a reinforcing portion is provided at the tip of the elastic tongue, the tip mass of the elastic tongue is increased, and the elastic elastic deformation of the elastic tongue itself may be increased. This is because the deformation reaction becomes dull and it is difficult to quickly open the slit.

  In particular, the elastic tongue piece is integrally formed of a rubber elastic body, so that the deformation of the elastic tongue piece can be easily stabilized without increasing the number of parts or complicating the manufacturing process. This can be realized, and the adverse effect on the anti-vibration characteristics exhibited by the displacement and deformation of the movable rubber plate itself can be avoided.

In the fluid filled type vibration damping device according to the first aspect of the present invention, the hydraulic pressure absorbing rubber plate is provided with a plurality of radially extending slits, and the elastic tongue pieces are arranged around the radial centers of the slits. A configuration is adopted in which a plurality are formed in the circumferential direction between adjacent slits.

  In the fluid-filled vibration isolator of this aspect, in particular, three or more slits are formed at appropriate intervals in the circumferential direction, for example, at equal intervals, so that a plurality of elastic tongue pieces having a fan-shaped flat plate shape are excellent. It can be easily formed with space efficiency.

In the fluid-filled vibration isolator according to the first aspect of the present invention, the reinforcing portion of the elastic tongue piece is located on the inner peripheral side of a circumscribed circle connecting the tips of the plurality of radially extending slits. The formed structure is adopted .

In the fluid-filled vibration isolator of this aspect, each elastic tongue formed by a radial slit suppresses the adverse effect on the spring characteristics at the base end portion, and particularly each elasticity considered to be easily elastically deformed irregularly. An intermediate portion in the length direction of the tongue piece can be efficiently reinforced. Therefore, the effect of preventing cavitation noise due to deformation of each elastic tongue and opening the slit when a shocking large load is input, and the orifice passage and liquid by stabilizing the deformation of each elastic tongue. It is possible to realize both the vibration-proofing effect of the pressure absorbing mechanism and the higher level of both.
In the fluid filled type vibration damping device according to the first aspect of the present invention, the reinforcing portion of the elastic tongue piece is constituted by a protrusion extending over the entire length in the width direction of the elastic tongue piece.
In the fluid-filled vibration isolator of this aspect, the unstable deformation of the elastic tongue is efficiently suppressed without greatly degrading the deformation characteristics of the elastic tongue for opening the slit when avoiding excessive pressure in the pressure receiving chamber. This is effective even when the width of the elastic tongue is large. Further, in this aspect, each elastic tongue piece is formed in a fan shape by a plurality of radially extending slits, and the reinforcing portion of each elastic tongue piece is an annular protrusion extending in the circumferential direction around the radial center of the slit. It is formed by a strip. In addition, it is also possible to form a plurality of protrusions of this aspect at a predetermined distance in the length direction of the elastic tongue piece.

According to a second aspect of the present invention, in the fluid-filled vibration isolator according to the first aspect, the reinforcing portion of the elastic tongue piece includes rubber protrusions protruding toward both front and back sides of the elastic tongue piece. It is configured.

  In the fluid-filled vibration isolator of this aspect, the elastic tongue piece has a reinforcing effect that is substantially the same on both the front and back sides, so that the elastic characteristics of the elastic tongue piece are stable, and the elastic tongue piece by the reinforcing portion The unstable deformation suppressing effect 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 hydraulic pressure absorbing rubber plate includes a hard reinforcing plate having higher rigidity than the hydraulic pressure absorbing rubber plate. The rigid reinforcing plate is formed with a through-hole in the thickness direction, and the slit is provided in a portion of the hydraulic pressure absorbing rubber plate that covers the through-window so that the elastic tongue piece Is formed.

  In the fluid-filled vibration isolator of this aspect, the elastic deformation of the hydraulic pressure absorbing rubber plate itself is limited by the hard reinforcing plate, thereby preventing excessive deformation and irregular deformation of the hydraulic pressure absorbing rubber plate. Therefore, the adverse effect on the vibration isolation effect of the orifice passage due to the overall excessive deformation of the hydraulic pressure absorbing rubber plate is prevented, and the intended vibration isolation effect can be obtained more advantageously. Further, since the elastic tongue pieces are also provided with the reinforcing action of the hard reinforcing plate on the base end side, the stability of the deformation mode of the elastic tongue pieces can be further improved.

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, a displacement in the thickness direction of the hydraulic pressure absorbing rubber plate is allowed and a displacement amount is limited. And the rubber plate support part which supports this hydraulic pressure absorption rubber plate is provided in the partition member supported by said 2nd attachment member.

  In the fluid-filled vibration isolator of this aspect, the displacement amount of the hydraulic pressure absorbing rubber plate is surely limited, thereby preventing the orifice passage from being caused by the overall excessive deformation or excessive displacement of the hydraulic pressure absorbing rubber plate. An adverse effect on the vibration effect can be prevented. Specifically, for example, when the hydraulic pressure absorbing rubber plate is hard by including the hard reinforcing plate according to the sixth aspect, the outer peripheral portion of the hydraulic pressure absorbing rubber plate is predetermined on both sides in the plate thickness direction. The rubber plate support portion of this aspect can be realized by a concave annular groove that is supported with a gap of 5 mm. In the case of a hydraulically absorbing rubber plate that is not provided with such a hard reinforcing plate and can be elastically deformed, for example, a regulating plate having a plurality of through holes is provided on both sides in the thickness direction of the hydraulically absorbing rubber plate. The rubber plate support portion can be realized by disposing with a predetermined gap and limiting the amount of displacement by the contact of the hydraulic pressure absorbing rubber plate to both the restriction plates.

  In the fluid-filled vibration isolator having a structure according to the present invention, the irregular deformation of the elastic tongue piece is suppressed by the reinforcing portion at the time of normal vibration input, so that the orifice passage and the hydraulic pressure absorbing rubber plate The anti-vibration effect can be sufficiently secured. Moreover, when an excessive pressure fluctuation is induced in the pressure receiving chamber due to an input of a shocking heavy load, the elastic tongue piece elastically deforms and the pressure in the pressure receiving chamber is quickly eliminated through the slit, thereby causing cavitation, etc. This problem can be effectively prevented.

It is a longitudinal cross-sectional view which shows the fluid enclosure type vibration isolator as 1st embodiment of this invention, Comprising: II sectional drawing of FIG. The top view of the movable member which comprises the fluid enclosure type vibration isolator. The bottom view of the movable member. IV-IV sectional drawing of FIG. VV sectional drawing of FIG. The top view of the movable member as a reference form of this invention. The bottom view of the movable member. VIII-VIII sectional drawing of FIG.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 shows a fluid-filled vibration isolator 10 as a first embodiment according to the present invention. This fluid-filled vibration isolator 10 includes a first attachment member 12 attached to one member to be vibration-isolated and a second attachment member 14 attached to the other member to be anti-vibration connected. The elastic bodies 16 are elastically connected to each other. And, for example, the first mounting member 12 is attached to the power unit of the automobile which is one member to be vibration-proof connected, and the second mounting member 14 is attached to the body of the automobile which is the other member to be vibration-proof connected. As a result, the power unit is supported by the vehicle body in a vibration-proof manner. In the following description, the vertical direction means the vertical direction in FIG. 1 which is the main vibration input direction in principle.

  More specifically, the first mounting member 12 is a highly rigid member made of a metal material such as iron or aluminum alloy, and has a substantially circular block shape. Further, a flange portion 18 that extends outward in the radial direction is integrally formed at the upper end portion of the first mounting member 12. Further, a bolt hole 20 is formed so as to open on the upper end surface of the first mounting member 12 and extend on the central axis, and a female screw is engraved on the inner peripheral surface of the bolt hole 20. The first mounting member 12 is bolted to a power unit (not shown) by, for example, a mounting bolt (not shown) screwed into the bolt hole 20.

  On the other hand, the second mounting member 14 is a highly rigid member formed of the same metal material as the first mounting member 12, and has a thin cylindrical shape with a large diameter as a whole. In addition, a constricted portion 22 is provided at an intermediate portion in the axial direction of the second mounting member 14. The constricted portion 22 includes a tapered portion 24 that gradually decreases in diameter toward the lower side in the axial direction, and an annular stepped portion 26 that widens from the lower end portion of the tapered portion 24 toward the outer peripheral side. An annular step 28 that extends toward the outer peripheral side is formed at the lower end of the second mounting member 14, and an annular shaped caulking piece that extends downward on the outer peripheral edge of the step 28. 30 is integrally formed. Such a second mounting member 14 is fixed to the vehicle body, for example, by attaching a bracket (not shown) that is fitted and fixed to the second mounting member 14 to the vehicle body.

  The first mounting member 12 and the second mounting member 14 as described above are disposed on the same central axis, and the first mounting member 12 is spaced apart from the second mounting member 14 in the axial direction. Has been placed. The main rubber elastic body 16 is interposed between the first mounting member 12 and the second mounting member 14 so that the first mounting member 12 and the second mounting member 14 are the main rubber elastic body. 16 is elastically connected.

  The main rubber elastic body 16 is formed of a rubber elastic body having a thick, substantially truncated cone shape. Further, a large-diameter circular recess 32 is formed in the central portion in the radial direction of the main rubber elastic body 16 so as to open to the large-diameter side end surface (the lower end surface in FIG. 1). Further, the first mounting member 12 is inserted into the small diameter side end portion of the main rubber elastic body 16 so that the lower surface of the flange portion 18 is overlapped with the small diameter side axial end surface of the main rubber elastic body 16. And vulcanized. On the other hand, the upper portion of the second mounting member 14 and the taper portion 24 are overlapped and vulcanized and bonded to the outer peripheral surface of the large-diameter side end portion of the main rubber elastic body 16. Thereby, the first attachment member 12 and the second attachment member 14 are connected to each other by the main rubber elastic body 16. The main rubber elastic body 16 in the present embodiment is formed as an integrally vulcanized molded product that integrally includes the first mounting member 12 and the second mounting member 14.

  Further, a seal rubber layer 34 integrally formed with the main rubber elastic body 16 is fixed to the inner peripheral surface of the second mounting member 14. The seal rubber layer 34 is formed of a thin rubber film, and is formed so as to cover a portion extending from the inner peripheral surface of the step portion 26 to the inner peripheral portion of the step 28 in the second mounting member 14.

  A flexible film 36 is disposed at the lower end opening of the second mounting member 14. The flexible film 36 is formed of a rubber film having a thin, large-diameter, generally circular dome shape, so that elastic deformation is easily allowed. A fixing metal fitting 38 is fixed to the outer peripheral edge of the flexible film 36. The fixing bracket 38 has a substantially annular shape, and is integrally provided with a cylindrical fixing portion 40 and a hook-like portion 42 that extends from the upper end of the fixing portion 40 toward the outer peripheral side. Then, the outer peripheral edge of the flexible membrane 36 is vulcanized and bonded to the fixing portion 40 of the fixing bracket 38, so that the flexible membrane 36 is integrally provided with the fixing bracket 38. It is formed as. In the present embodiment, the fixing fitting 38 is covered with a rubber layer integrally formed with the flexible film 36 over substantially the entire surface excluding the outer peripheral edge and the upper end surface of the bowl-shaped portion 42.

  Such a flexible membrane 36 is assembled to the second attachment member 14. That is, the outer peripheral edge portion of the hook-shaped portion 42 of the fixing bracket 38 is superimposed on the step 28 provided at the lower end portion of the second mounting member 14 from below, and the hook-shaped portion 42 is attached to the second mounting member 14. The flexible membrane 36 is fixed to the lower end portion of the second attachment member 14 by being caulked and fixed by the caulking piece 30 formed integrally with the member 14.

  As described above, the flexible film 36 is assembled to the integrally vulcanized molded product of the main rubber elastic body 16 including the first mounting member 12 and the second mounting member 14, thereby the second mounting member. 14 is closed fluid-tightly by the main rubber elastic body 16, and the axially lower opening of the second mounting member 14 is fluid-tightly closed by the flexible membrane 36. ing. Thereby, a fluid sealing region 44 as a fluid chamber sealed from the outside is formed between the main rubber elastic body 16 and the flexible film 36 on the inner peripheral side of the second mounting member 14. .

  In addition, in the fluid sealing region 44, incompressible fluid such as water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixed solution thereof is sealed as a sealing fluid. The sealed fluid is not particularly limited, but the viscosity is 0.1 Pa · s or less in order to advantageously obtain a vibration isolating effect based on the resonance action of the fluid flowing in the orifice passage 68 described later. It is desirable to employ a low viscosity fluid. In addition, such fluid sealing does not attach the flexible membrane 36 to the second mounting member 14 (an integral vulcanization molded product of the main rubber elastic body 16 provided with the second mounting member 14). By carrying out in a compressible fluid, it can be advantageously realized.

  A partition member 46 is accommodated in the fluid sealing area 44. The partition member 46 has a thick, substantially disk shape, and is configured to include a partition member main body 48 and a lid member 50 in the present embodiment.

  The partition member body 48 as a whole has a thick, substantially disk shape, and is formed of a hard material such as iron, an aluminum alloy, or a hard synthetic resin material in the present embodiment. In addition, a notch-shaped groove 52 that opens to the upper end surface and the outer peripheral surface is formed in the outer peripheral edge of the partition member main body 48 so as to extend in the circumferential direction with a predetermined length shorter than one round.

  In addition, an accommodation recess 54 is formed in the central portion of the partition member body 48 in the radial direction. The accommodation recess 54 is formed in the partition member main body 48 at a predetermined distance on the inner peripheral side of the notch-shaped groove 52, and is a circular recess that opens upward. Further, a lower central recess 56 is formed in the central portion of the partition member body 48 in the radial direction. The lower central recess 56 is a circular recess formed in the partition member main body 48 at a position substantially corresponding to the housing recess 54 in the vertical direction, and is opened downward in the axial direction.

  On the other hand, the lid member 50 has a thin disk shape having substantially the same diameter as the partition member main body 48, and is formed of the same hard material as the partition member main body 48 in the present embodiment. And the partition member 46 in this embodiment is comprised by overlapping and combining the cover member 50 with respect to the upper end surface of the partition member main body 48 from upper direction.

  As described above, the lid member 50 is overlapped with the partition member main body 48, so that the upper opening of the notch-shaped groove 52 is covered with the lid member 50 and opens to the outer peripheral surface of the partition member 46 in the circumferential direction. A circumferential groove extending in the direction is formed using the notched groove 52. Further, the opening portion of the housing recess 54 formed in the partition member main body 48 is covered with the lid member 50, so that a housing region 58 is formed inside the partition member 46.

  Such a partition member 46 is disposed in the fluid sealing region 44 in a housed state. That is, the partition member 46 is inserted from the lower opening of the second mounting member 14, and the outer peripheral edge of the lid member 50 is brought into contact with the stepped portion 26 of the second mounting member 14 from below. At the same time, the hook-shaped portion 42 of the fixing bracket 38 is superimposed on the outer peripheral edge of the partition member main body 48 from below. Then, when the hook-shaped portion 42 of the fixing bracket 38 is fixed to the second mounting member 14 by the caulking piece 30 of the second mounting member 14, the partition member 46 becomes the stepped portion of the second mounting member 14. 26 and the hook-like portion 42 of the fixing bracket 38, and fixedly supported by the second mounting member 14. In this embodiment, the partition member 46 is inserted into the second mounting member 14 and subjected to a diameter reduction process such as an eight-way drawing on the second mounting member 14. The outer peripheral surface is brought into close contact with the second mounting member 14 via the seal rubber layer 34.

  In this way, the partition member 46 is disposed so as to extend in the direction perpendicular to the axis in the fluid sealing region 44 and is supported by the second mounting member 14, so that the fluid sealing region 44 has a shaft with the partition member 46 interposed therebetween. The direction is divided into upper and lower sides. That is, on one side (upper side) sandwiching the partition member 46, a part of the wall portion is constituted by the main rubber elastic body 16, and a pressure receiving chamber 60 is formed in which pressure fluctuation is caused when vibration is input. On the other side (lower side) across the partition member 46, a part of the wall portion is formed of the flexible film 36, and an equilibrium chamber 62 in which volume change is allowed by deformation of the flexible film 36 is formed. Has been. The pressure receiving chamber 60 and the equilibrium chamber 62 are filled with the incompressible fluid sealed in the fluid sealing region 44.

  Moreover, the outer peripheral side opening part of the said circumferential groove formed in the outer peripheral part of the partition member 46 is covered fluid-tightly by the 2nd attachment member 14, and the outer peripheral part of the partition member 46 is made into the circumferential direction. A tunnel-shaped passage extending in a predetermined length is formed. Further, the lid member 50 is formed with an upper communication passage 64 that opens one end of the tunnel-shaped passage above the partition member 46, and the partition member body 48 has the other end of the tunnel-shaped passage. A lower communication passage 66 is formed to open the end of the lower portion below the partition member 46. One end of the tunnel-shaped passage communicates with the pressure receiving chamber 60 through the upper communication passage 64, and the other end of the tunnel-shaped passage communicates with the equilibrium chamber 62 through the lower communication passage 66. An orifice passage 68 that communicates the pressure receiving chamber 60 and the equilibrium chamber 62 with each other is formed. In the present embodiment, the ratio between the passage length of the orifice passage 68 and the passage sectional area is appropriately set according to the rigidity of the wall spring of the pressure receiving chamber 60, so that the two chambers 60, 62 are connected through the orifice passage 68. The resonance frequency of the fluid to be flowed is tuned to a low frequency of about 10 Hz corresponding to an engine shake of an automobile.

  Here, a movable member 70 as shown in FIGS. 2 to 5 is accommodated in the accommodating region 58 formed in the partition member 46. The movable member 70 has a substantially disc shape as a whole, and is constituted by a hydraulic pressure absorbing rubber plate 72 and a hard reinforcing plate 74 as a restraining plate.

  The hydraulic pressure absorbing rubber plate 72 is a rubber elastic body having a substantially disc shape, and the outer diameter dimension thereof is slightly smaller than the inner diameter dimension of the accommodation region 58. Further, the thickness of the hydraulic pressure absorbing rubber plate 72 is also slightly smaller than the height of the accommodating area 58, and the upper and lower surfaces of the hydraulic absorbing rubber plate 72 are accommodated while being disposed in the accommodating area 58. Due to the gap existing between the upper and lower inner surfaces of the region 58, the displacement of the hydraulic pressure absorbing rubber plate 72 in the housing region 58 in the thickness direction is allowed. On the outer peripheral surface of the hydraulic pressure absorbing rubber plate 72, positioning protrusions 76 that protrude with a lip shape extending in the circumferential direction are integrally formed at a plurality of locations on the circumference. The plurality of positioning protrusions 76 position the hydraulic pressure absorbing rubber plate 72 at the approximate center within the accommodation region 58, and displacement in the plate thickness direction is allowed with a small contact resistance.

  Furthermore, a substantially disc-shaped hard reinforcing plate 74 is disposed in a state of being embedded in the middle portion in the thickness direction of the hydraulic pressure absorbing rubber plate 72 and is vulcanized and bonded to the hydraulic pressure absorbing rubber plate 72. . The hard reinforcing plate 74 is formed of a synthetic resin material, a metal material, or the like having a rigidity higher than that of the hydraulic pressure absorbing rubber plate 72. The outer diameter of the hard reinforcing plate 74 is smaller than the outer diameter of the hydraulic pressure absorbing rubber plate 72, and the elastic deformation of the central portion of the hydraulic absorbing rubber plate 72 is substantially caused by the hard reinforcing plate 74. It is blocked.

  In this embodiment, the upper and lower elastic contact portions 78 and 78 projecting on both sides in the plate thickness direction at the outer peripheral edge portion of the hydraulic pressure absorbing rubber plate 72 positioned away from the outer peripheral side of the hard reinforcing plate 74 are It is integrally formed in an annular shape continuous in the direction. The protrusion height of the upper and lower elastic contact portions 78, 78 is continuously changed in the circumferential direction, so that the outer peripheral edge portion of the hydraulic pressure absorbing rubber plate 72 is on both sides in the plate thickness direction in the circumferential direction. It is made into the wavy part extended like a wave. That is, the outer peripheral edge of the hydraulic pressure absorbing rubber plate 72 does not substantially change the dimension in the thickness direction including the upper and lower elastic contact portions 78, 78, and the center position in the thickness direction is vertically changed in the circumferential direction. It has been changed to swing. In particular, in the present embodiment, the projecting tip surfaces of the upper and lower elastic contact portions 78, 78 have a shape that is smoothly waved in the circumferential direction at a constant cycle (for example, a cycle of 90 degrees in the circumferential direction) in a substantially sine wave shape. .

  The hard reinforcing plate 74 is formed with a plurality of through windows 80 penetrating in the plate thickness direction. In the present embodiment, each through window 80 is formed as a circular hole, and four through windows 80 are formed at equal intervals in the circumferential direction at the radial intermediate portion of the hydraulic pressure absorbing rubber plate 72. Each through window 80 is covered with a rubber valve plate 82 made of a single hydraulic pressure absorbing rubber plate 72.

  The rubber valve plate 82 has a disk shape that expands with a substantially constant thickness. On the outer peripheral portion of the rubber valve plate 82, buffer ribs 84 that are located on the inner peripheral edge portion of the through window 80 of the hard reinforcing plate 74 and project on both sides in the thickness direction are integrally formed in an annular shape over the entire circumference. . The protruding height of the buffer rib 84 is set so as to protrude most outward in the thickness direction on the entire surface of the hydraulic pressure absorbing rubber plate 72. In the outer peripheral portion of each rubber valve plate 82, buffer ribs 84, 84 projecting from the upper and lower surfaces of the hydraulic pressure absorbing rubber plate 72 are formed, whereby the outer peripheral portion of the rubber valve plate 82 is reinforced and liquid The impact at the time of contact with the inner surface of the accommodation area 58 of the pressure absorbing rubber plate 72 is reduced.

  Further, a slit 86 is formed in the rubber valve plate 82. A plurality of slits 86 are formed so as to extend radially outward from the center of the rubber valve plate 82 and penetrate the rubber valve plate 82 in the thickness direction. In the present embodiment, as shown in FIGS. 2 and 3, three slits 86 are formed at equal intervals around the radiation center, and between the adjacent slits 86, 86 in the circumferential direction, a sector shape is formed. Elastic tongue pieces 88 each having a flat plate shape are formed. That is, in the elastic tongue 88, the radial center point of the plurality of slits 86, 86, 86 is the tip of the elastic tongue 88, and the slits on both sides of the elastic tongue 88 are centered on the radial center point. A portion located on a line of an arc extending by connecting the tips of 86 and 86 is a base end portion of the elastic tongue 88.

Each slit 86 has a length that does not reach the outer peripheral edge of the rubber valve plate 82. In particular, in the present embodiment, each slit 86 has a length that does not reach the buffer rib 84 slightly. 86 is formed. Each slit 86 is closed in an initial state where no external force is applied, and both end surfaces in the circumferential direction of each rubber valve plate 82 are in the circumferential end surfaces of the rubber valve plates 82 adjacent to each other across the slit 86. On the other hand, the slits 86 are closely overlapped over the entire length. However, the slit 86 does not need to be completely closed according to the required vibration isolation characteristics, and the circumferential end surfaces of the elastic tongue pieces 88 adjacent in the circumferential direction may be slightly separated from each other. .

  Further, each elastic tongue 88 is integrally formed with a reinforcing portion 90 that is a partially thick rubber protrusion. The reinforcing portion 90 in the elastic tongue 88 is constituted by a protrusion that extends in the width direction of the elastic tongue 88. The width direction of the elastic tongue piece 88 is a direction orthogonal to the length direction extending from the base end portion of the elastic tongue piece 88 to the distal end portion, and is also a direction extending orthogonally to the slit 86. In the present embodiment, the reinforcing portion 90 is formed in each elastic tongue 88 with an arc shape extending in the circumferential direction of a circle centered on the radial center of the slit 86. Further, in the present embodiment, the reinforcing portion 90 is formed in a region surrounded by a circumscribed circle connecting the tips of the radially extending slits 86 in the elastic tongue 88. Further, it is desirable that the reinforcing portion 90 is formed at an intermediate portion in the length direction from the base end portion to the tip end portion of the elastic tongue 88, and is particularly biased to the outer peripheral side from the center in the length direction. Specifically, on both the front and back surfaces of the rubber valve plate 82, elastic ridges extending continuously in the circumferential direction around the radial center of the radially extending slit 86 and having a mountain-shaped cross section are formed. By being divided, an independent reinforcing portion 90 is formed for each elastic tongue 88.

  In addition, it is preferable that the reinforcement parts 90 and 90 formed in the front and back both surfaces of each elastic tongue piece 88 are the same size and the same size mutually, and are formed symmetrically. Thereby, the shape of the elastic tongue 88 is stabilized, and the elastic deformation effect can be sufficiently exhibited. Further, in this embodiment, in the cross section of the reinforcing portion 90, the top portion is biased toward the outer peripheral side, and the curvature radius on the inner peripheral side is made larger than the curvature radius on the outer peripheral side of the reinforcing portion 90, and is gentle. It is inclined to. Thus, in the elastic tongue 88, the distal end portion located on the center side of the rubber valve plate 82 has a smaller width in the circumferential direction than the proximal end portion located on the outer peripheral side of the rubber valve plate 82, and is easily deformed. In consideration of the above characteristics, the characteristic change exerted on the rubber valve plate 82 by the formation of the reinforcing portions 90, 90 is reduced. Further, it is desirable that the protruding height dimension of the reinforcing portion 90 is 30 to 100% of the thickness dimension of the elastic tongue 88. This is because if the reinforcing portion 90 is too small, it is difficult to obtain a sufficient reinforcing effect, and if it is too large, there is a concern about adverse effects on the elastic characteristics of the elastic tongue 88 and the like.

  The movable member 70 having such a structure is disposed in an accommodation region 58 formed inside the partition member 46, and the movable member 70 is arranged in the thickness direction in the accommodation region 58 as described above. It can be displaced by a predetermined distance. Further, an upper through hole 96 penetrating in the axial direction is formed in the central portion of the lid member 50 constituting the upper side wall portion of the containing area 58, and the containing area 58 communicates with the pressure receiving chamber 60 through the upper through hole 96. Has been. On the other hand, a lower through hole 98 penetrating in the axial direction is formed in the central portion of the partition member main body 48 (the bottom wall portion of the housing recess 54) constituting the lower wall portion of the housing area 58, and the lower side The accommodation region 58 communicates with the equilibrium chamber 62 through the through hole 98.

  In the present embodiment, the upper and lower through holes 96 and 98 are both large-diameter circular holes, and the upper and lower through holes 96 and 98 are formed with substantially the same diameter. The inner diameter of the upper and lower through holes 96 and 98 is smaller than the outer diameter of the hard reinforcing plate 74 in the movable member 70, and the region where the hard reinforcing plate 74 is disposed in the movable member 70 is the upper and lower through holes. The amount of displacement of the movable member 70 in the plate thickness direction is reliably defined by contacting the outer peripheral portions 96 and 98.

  In short, by forming the upper and lower through holes 96, 98, the partition member 46 is formed with an annular groove that opens to the inner peripheral surface and extends in the circumferential direction. The outer peripheral part of 70 is inserted. Since the movable member 70 is supported by the second mounting member 14 via the partition member 46 so as to be displaceable in a region where the amount of displacement is limited by contact with the inner surface of the annular groove. is there. As is clear from this, in this embodiment, the partition member 46 constitutes a rubber plate support portion that supports the hydraulic pressure absorbing rubber plate 72 so as to be displaceable.

  Furthermore, the size of the upper and lower through holes 96 and 98 is such that the rubber valve plate 82 provided in the movable member 70 is exposed to the pressure receiving chamber 60 and the equilibrium chamber 62 through the upper and lower through holes 96 and 98 in a sufficient area. Is set to be. Specifically, 50% or more, preferably 80% or more of each rubber valve plate 82 in the axial projection is preferably exposed to the pressure receiving chamber 60 and the equilibrium chamber 62 through the upper and lower through holes 96 and 98. .

  Thereby, the pressure of the pressure receiving chamber 60 is applied to the upper surface of the movable member 70 disposed in the accommodating region 58 through the upper through hole 96 and the equilibrium chamber is applied to the lower surface of the movable member 70. A pressure of 62 is applied through the lower through hole 98.

  Since the movable member 70 is disposed in the accommodating region 58 so as to partition the pressure receiving chamber 60 and the equilibrium chamber 62, a relative pressure difference is generated between the pressure receiving chamber 60 and the equilibrium chamber 62 due to vibration input. Then, the movable member 70 is slightly displaced in the axial direction to constitute a hydraulic pressure absorbing mechanism that absorbs pressure fluctuations in the pressure receiving chamber 60.

  In the present embodiment, the outer peripheral edge of the hydraulic pressure absorbing rubber plate 72 extends to the outer peripheral side with respect to the upper and lower through holes 96 and 98, and the rigid reinforcing plate 74 to which the hydraulic pressure absorbing rubber plate 72 is fixed. Is formed in a disk shape having a larger diameter than the opening regions of the upper and lower through holes 96 and 98, and the outer peripheral edge of the hard reinforcing plate 74 is located on the outer peripheral side of the upper and lower through holes 96 and 98 over the entire circumference. It has spread. As a result, when a large amplitude vibration is input, the outer peripheral portion of the hydraulic pressure absorbing rubber plate 72 to which the hard reinforcing plate 74 is fixed is brought into contact with the upper and lower inner surfaces of the accommodation region 58, so that the axial direction of the movable member 70 is reached. The displacement at is more reliably limited.

  In addition, when the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 is extremely large, the slit 86 is opened by elastic deformation of the elastic tongue 88 formed on the rubber valve plate 82, and the slit 86 passes through the slit 86. The pressure receiving chamber 60 and the equilibrium chamber 62 are communicated with each other. As a result, a short-circuit mechanism is configured to allow the pressure receiving chamber 60 and the equilibrium chamber 62 to communicate with each other with a smaller flow resistance than that of the orifice passage 68 when a shocking large load is input. In short, in the present embodiment, the short-circuit mechanism is realized by a valve structure that switches between the communication state and the cutoff state of the slit 86 by using the elasticity of the elastic tongue 88.

  In the fluid-filled vibration isolator 10 having such a structure, when low-frequency large-amplitude vibration corresponding to an engine shake of an automobile is input while being mounted on a vehicle, the pressure receiving chamber 60 and the equilibrium chamber 62 are relative to each other. Based on the pressure fluctuation, fluid flow is generated through the orifice passage 68 tuned to the low frequency range. At this time, since the relative pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 exceeds the hydraulic pressure absorbing function due to the displacement of the movable member 70, the displacement amount of the movable member 70 is limited and substantially restrained. Therefore, the amount of fluid flow through the orifice passage 68 is effectively ensured, and the vibration isolation effect (high damping effect) based on the fluid action such as the resonance action of the fluid can be effectively exhibited.

  In addition, when a low-frequency large-amplitude vibration corresponding to a normal engine shake is input, the pressure fluctuation in the pressure receiving chamber 60 is released to the equilibrium chamber 62 by the fluid flow through the orifice passage 68, and the pressure fluctuation in the pressure receiving chamber 60 is remarkably increased. It won't grow. Therefore, also in the movable member 70, the slit 86 is held in a closed state against the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62 due to the elasticity of the elastic tongue 88. Therefore, escape of the pressure in the pressure receiving chamber 60 through the slit 86 is prevented, the fluid flow through the orifice passage 68 based on the relative pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62, and the vibration isolation performance based on the fluid flow. Can be more effectively exhibited.

  In addition, when a small amplitude vibration in the middle to high frequency range corresponding to idling vibration or traveling noise is input, the orifice passage 68 is substantially cut off due to anti-resonant action. At this time, the movable member 70 is allowed to be slightly displaced in the plate thickness direction based on the relative pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62, so that the pressure fluctuation induced in the pressure receiving chamber 60 is reduced to the equilibrium chamber 62 side. The hydraulic pressure absorbing action that is absorbed and absorbed is exhibited. Therefore, a significant increase in the dynamic spring associated with the substantial blocking of the orifice passage 68 is avoided, and a good vibration isolation performance is exhibited. It should be noted that, even in the middle to high frequency range corresponding to idling vibration or traveling noise, the pressure variation in the pressure receiving chamber 60 is released to the equilibrium chamber 62 based on the displacement of the movable member 70, so that the slit 86 is formed. It is maintained in a substantially closed state.

  On the other hand, when a shocking large load is input due to overcoming a step during traveling and the like, a significant pressure fluctuation occurs in the pressure receiving chamber 60, each of the rubber valve plates 82 in the rubber valve plate 82 is based on the pressure difference between the pressure receiving chamber 60 and the equilibrium chamber 62. The elastic tongue 88 is greatly deformed, and the slit 86 is opened. Then, the pressure receiving chamber 60 and the equilibrium chamber 62 are communicated with each other through the slit 86, and by the fluid flow through the slit 86, extremely significant pressure fluctuations in the pressure receiving chamber 60 can be eliminated as quickly as possible. Therefore, for example, the generation of cavitation in the pressure receiving chamber 60 can be suppressed, and the generation of abnormal noise and vibration due to cavitation can be prevented.

  Here, the elastic tongue piece 88 in the rubber valve plate 82 is partially thickened to form a reinforcing portion 90. As a result, the elastic tongue piece 88 is elastically deformed to secure the characteristic of opening the slit 86, and the local deformation rigidity of the elastic tongue piece 88 is enhanced to stabilize the deformation of the elastic tongue piece 88. Yes. Therefore, when a shocking heavy load is input, the slit 86 can be opened to suppress significant pressure fluctuations in the pressure receiving chamber 60, and the orifice passage 68 such as engine shake, idling vibration, traveling booming noise, and the like can be absorbed. At the time of normal vibration input in which the anti-vibration effect is exhibited by the mechanism, irregular deformation of the elastic tongue 88 and unexpected opening of the slit 86 due to it are effectively prevented, and the orifice passage 68 and the hydraulic pressure absorbing mechanism are effectively prevented. Therefore, the desired vibration-proofing effect can be effectively exhibited.

  In particular, since the reinforcing portion 90 of the elastic tongue 88 is provided at an intermediate portion in the length direction of the elastic tongue 88, the elastic deformation characteristics at the base end portion of the elastic tongue 88 due to the formation of the reinforcing portion 90. And problems associated with an increase in mass at the tip of the elastic tongue 88 can be avoided. Therefore, by forming the reinforcing portion 90 as described above in the elastic tongue 88, while sufficiently ensuring the characteristics such as cavitation prevention exhibited based on the opening of the slit 86 at the time of shocking heavy load input, This makes it possible to effectively prevent the vibration-proof performance from deteriorating due to irregular deformation or resonance of the elastic tongue 88 during normal running or the like.

  Further, in this embodiment, the movable member 70 in which the hard reinforcing plate 74 is fixed to the hydraulic pressure absorbing rubber plate 72 formed of a rubber elastic body is employed, and the rubber valve plate 82 is surrounded by the hard reinforcing plate 74. It is reinforced. Since the reinforcing effect by the hard reinforcing plate 74 is also exerted on each elastic tongue 88, the deformation of the elastic tongue 88 can be further stabilized.

  Furthermore, in this embodiment, since the outer peripheral side of the rubber valve plate 82 is reinforced by the upper and lower buffer ribs 84, 84, cracks at the tip portion of the slit 86 are prevented, and excellent durability can be realized. Even if a crack occurs in the tip portion of the slit 86, the growth of the crack can be prevented by the hard reinforcing plate 74 disposed on the outer peripheral side of the rubber valve plate 82.

  As mentioned above, although embodiment of this invention has been described, this invention is not interpreted limitedly by the specific description in this embodiment.

For example, in the above-described embodiment, the radial slit 86 configured by linear notches extending in three directions is illustrated, but the specific shape of the slit 86 is not particularly limited .

Further, the reinforcing portion 90 formed on the elastic tongue 88 may be formed only on one of the upper surface and the lower surface, and by adopting mutually different sizes and shapes, the upward deformation characteristics and the downward direction. It is also possible to make the deformation characteristics different from each other .
In addition, as a reference form of this invention, the aspect which comprises a reinforcement part with the one or several elastic protrusion 100 independent in the elastic tongue piece 88 is shown to FIGS. 6 to 8, in order to facilitate the understanding, the same reference numerals as those of the above embodiment are given to members and parts having the same structure as that of the above embodiment.

  In the embodiment, the plurality of through windows 80 are formed in the hard reinforcing plate 74 constituting the movable member 70, but a structure in which only one through window 80 is formed may be used. Further, the hard reinforcing plate 74 is not essential in the present invention, and the movable member 70 can be constituted by a single unit of the hydraulic pressure absorbing rubber plate 72 to which the hard reinforcing plate 74 is not fixed.

  Moreover, in the said embodiment, the movable member 70 comprised by the hydraulic pressure absorption rubber plate 72 is comprised by the component independent from the partition member 46, and is supported by the partition member 46 so that a micro displacement is possible in a plate | board thickness direction. However, the outer peripheral portion of the movable member 70 constituted by the hydraulic pressure absorbing rubber plate 72 can be fixedly supported by vulcanizing and adhering to the partitioning member 46 or holding it under pressure. is there. Thus, in the movable membrane structure in which the outer peripheral edge of the hydraulic pressure absorbing rubber plate 72 is fixedly supported by the partition member, the hydraulic pressure absorbing function can be exhibited based on the elastic deformation of the hydraulic pressure absorbing rubber plate 72.

  In addition, the elastic contact portion 78 and the buffer rib 84 that reduce the contact impact on the partition member 46 in the hydraulic pressure absorbing rubber plate 72 are provided as necessary. It is not limited. For example, in the above embodiment, the buffer ribs 84, 84 are formed on the outer peripheral portion of the rubber valve plate 82, but in addition to or instead of them, rubber protrusions and rubber protrusions protruding from the surface of the hard reinforcing plate 74, You may provide the buffer protrusion which consists of embossing etc.

  In the above embodiment, the upper and lower through holes 96 and 98 having large diameters are formed in the partition member 46, so that the front and back surfaces of the elastic tongues 88 formed in the movable member 70 are directly connected to the pressure receiving chamber 60 and the equilibrium. Although exposed to the chamber 62, for example, a plurality of small-diameter holes are formed instead of the large-diameter upper and lower through holes 96 and 98, and the pressure in the pressure receiving chamber 60 and the equilibrium chamber 62 is reduced through these small-diameter holes. It may be applied to each elastic tongue 88.

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

10: fluid-filled vibration isolator, 12: first mounting member, 14: second mounting member, 16: main rubber elastic body, 36: flexible membrane, 60: pressure receiving chamber, 62: equilibrium chamber, 68 : Orifice passage, 72: Hydraulic pressure absorbing rubber plate, 74: Hard reinforcing plate, 80: Through window, 86: Slit, 88: Elastic tongue piece, 90: Reinforcing part

Claims (7)

The first mounting member and the second mounting member are connected by a main rubber elastic body, a pressure receiving chamber in which a part of the wall portion is configured by the main rubber elastic body, and a part of the wall portion is flexible. Formed with an equilibrium chamber made of a conductive membrane, incompressible fluid is enclosed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber are communicated with each other by an orifice passage In the type vibration isolator,
A hydraulic pressure absorbing rubber plate is disposed between the pressure receiving chamber and the equilibrium chamber, and the pressure of the pressure receiving chamber is applied to one surface of the hydraulic pressure absorbing rubber plate, and the hydraulic pressure absorbing rubber When the pressure in the equilibrium chamber is exerted on the other surface of the plate, the pressure variation in the pressure receiving chamber is absorbed based on the displacement or deformation of the hydraulic pressure absorbing rubber plate based on the pressure difference between the pressure receiving chamber and the equilibrium chamber. While the hydraulic absorption mechanism is configured,
The hydraulic pressure absorbing rubber plate is formed with an elastic tongue by a slit, and the slit is opened by elastic deformation of the elastic tongue, and a short-circuit mechanism is configured to short-circuit the pressure receiving chamber and the equilibrium chamber. In addition, a fluid-filled type vibration damping device is characterized in that a thick reinforcing portion is integrally formed at an intermediate portion in the length direction from the base end portion to the tip end portion of the elastic tongue piece.   The hydraulic pressure absorbing rubber plate is provided with a plurality of radially extending slits, and a plurality of the elastic tongue pieces are formed in the circumferential direction between adjacent slits around the radial center of the slits. The fluid-filled vibration isolator according to claim 1.   The fluid-filled vibration isolator according to claim 2, wherein the reinforcing portion of the elastic tongue piece is formed on an inner peripheral side of a circumscribed circle connecting the tips of the plurality of radially extending slits. .   The fluid-filled vibration isolator according to any one of claims 1 to 3, wherein the reinforcing portion of the elastic tongue piece is constituted by rubber protrusions protruding toward both front and back sides of the elastic tongue piece.   The fluid-filled vibration isolator according to any one of claims 1 to 4, wherein the reinforcing portion of the elastic tongue piece is constituted by a protrusion extending in the width direction of the elastic tongue piece.   A rigid reinforcing plate having a rigidity higher than that of the hydraulic pressure absorbing rubber plate is fixed to the hydraulic pressure absorbing rubber plate, and a through-hole in the thickness direction is formed on the rigid reinforcing plate, and the hydraulic pressure absorbing plate is formed. The fluid-filled vibration isolator according to any one of claims 1 to 5, wherein the elastic tongue piece is formed by providing the slit in a portion of the absorbent rubber plate that covers the through window.   A rubber plate support portion for allowing the hydraulic pressure absorbing rubber plate to support displacement of the hydraulic pressure absorbing rubber plate while allowing displacement in a plate thickness direction and restricting the amount of displacement is provided on the second mounting member. Item 7. The fluid-filled vibration isolator according to any one of Items 1 to 6.

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