JP2013148192A - Fluid sealing type vibration-proof device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new fluid sealing type vibration-proof device capable of reducing hitting sound due to contact of a movable member and abnormal noises caused by cavitation in an easily manufactured structure.SOLUTION: A hollow buffer 72 having an internal space 74 is stored and arranged in a storage space 64 of a partition member 36, and comes in contact with an internal face of a wall at a pressure receiving chamber 66 side and an equilibrium chamber 68 side. Liquid pressure of a pressure receiving chamber 66 is applied to one face of a movable member 92 arranged on the internal space 74 through a first window section 80 of the buffer 72 and a first communication hole 44 of the storage space 64, and liquid pressure of the equilibrium chamber 68 is applied to the other face through a second window section 82 of the buffer 72 and a second communication hole 60 of the storage space 64. A communication passage 96 communicated with the first communication hole 44 is formed on a wall of the buffer 72 at a pressure receiving chamber 66 side, and a shortcut passage 98 continuously communicating between the pressure receiving chamber 66 and the storage space 64 by including the first communication hole 44 and the communication passage 96 is formed.

Description

  The present invention relates to an anti-vibration device used for, for example, an automobile engine mount, body mount, member mount, and the like, and more particularly, to a fluid-filled vibration-proof device using a vibration-proof effect based on a fluid action of a fluid sealed inside. Is.

  Conventionally, an anti-vibration device is known as a type of anti-vibration coupling body or anti-vibration support body interposed between members constituting a vibration transmission system. The vibration isolator has a structure in which a first attachment member and a second attachment member attached to one member constituting the vibration transmission system are elastically connected by a main rubber elastic body. As a vibration isolator, a fluid-filled vibration isolator using a fluid flow action is also known. In this fluid-filled vibration isolator, a pressure receiving chamber and an equilibrium chamber are formed across a partition member supported by a second mounting member, and an incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber. At the same time, the pressure receiving chamber and the equilibrium chamber are connected to each other through the orifice passage. For example, it is shown in Unexamined-Japanese-Patent No. 2009-243510 (patent document 1).

  In addition, the fluid-filled vibration isolator effectively exhibits the vibration isolation effect based on the fluid flow action against the vibration of the frequency at which the orifice passage is tuned, while the vibration at a frequency outside the tuning frequency. In contrast, it is difficult to obtain an effective anti-vibration effect. In particular, at the time of vibration input at a frequency higher than the tuning frequency, the orifice passage is substantially blocked by anti-resonance, which causes a problem of a reduction in vibration-proof performance due to the use of a high dynamic spring. Therefore, in the structure described in Patent Document 1, a hydraulic pressure transmission mechanism including a fluid flow path that allows transmission of hydraulic pressure between the pressure receiving chamber and the equilibrium chamber when a vibration having a frequency higher than the tuning frequency of the orifice passage is input. Is provided. Specifically, in this hydraulic pressure transmission mechanism, a movable member (movable plate) is accommodated in a housing space formed in the partition member, and a communication hole (fluid) formed through the wall portion of the housing space is formed. Each of the fluid pressure in the pressure receiving chamber and the fluid pressure in the equilibrium chamber is applied to both surfaces of the movable member through the flow path). When high-frequency small-amplitude vibration is input, the movable member is slightly displaced or deformed to allow hydraulic pressure to be transmitted between the pressure receiving chamber and the equilibrium chamber, and vibration in the tuning frequency range of the orifice passage is input. Then, the movable member closes the communication hole to prevent transmission of hydraulic pressure between the two chambers. As a result, the vibration isolation effect exhibited by the fluid flow through the orifice passage and the vibration isolation effect exhibited by the hydraulic pressure absorbing action by the hydraulic pressure transmission mechanism can be selectively and effectively obtained.

  By the way, in a fluid-filled vibration isolator, when a shocking large load is input and the pressure in the pressure receiving chamber drops significantly, abnormal noise is generated due to cavitation, resulting in quietness in the passenger compartment of an automobile. There is a problem of adversely affecting the system.

  Therefore, for the purpose of suppressing cavitation noise, JP 2009-2420 A (Patent Document 2) and the like form a short-circuit path in a partition member that separates the pressure-receiving chamber and the equilibrium chamber, and the short-circuit path is in a communication state. A structure having a relief valve for switching to a shut-off state has been proposed. According to this, since the pressure in the pressure receiving chamber is greatly reduced, the relief valve is opened and the short-circuit path is switched to the communication state, so that the negative pressure in the pressure-receiving chamber is quickly increased by the fluid flow through the short-circuit path. Therefore, the occurrence of abnormal cavitation noise is prevented.

  However, the structure described in Patent Document 2 requires processing for forming a short-circuit passage in a hard partition member and requires a special relief valve, which complicates the structure and reduces the number of parts. Increasing the size of the fluid-filled vibration isolator and the increase in the number of assembly steps are likely to cause problems.

  Even if the short-circuit passage is always in a communicating state without providing a relief valve, it is possible to obtain an effect of reducing cavitation noise, but short-circuiting is necessary to ensure vibration-proof performance against normal vibration input. It is necessary to set the passage cross-sectional area of the passage sufficiently small. However, when the partition member is a hard and thick member, it may be difficult to form a short-circuit passage having a small cross-sectional area, and it may be difficult to adopt such a structure. It was.

JP 2009-243510 A JP 2009-2420 A

  The present invention has been made in the background of the above-mentioned circumstances, and its solution is to reduce both the hitting sound caused by the abutment of the movable member and the abnormal noise caused by cavitation with an easily manufactured structure. An object of the present invention is to provide a fluid-filled vibration isolator having a novel structure.

  That is, according to the first aspect of the present invention, the first mounting member and the second mounting member are elastically connected by the main rubber elastic body, and the partition member supported by the second mounting member is sandwiched between the first mounting member and the second mounting member. A pressure receiving chamber in which a part of the wall portion is configured by the main rubber elastic body and an equilibrium chamber in which a part of the wall portion is configured by a flexible film are formed, and the pressure receiving chamber and the equilibrium chamber are incompressible. An orifice passage is formed in which fluid is sealed and the pressure receiving chamber and the equilibrium chamber communicate with each other. Further, a storage space is formed inside the partition member, and a movable member is formed in the storage space. And the hydraulic pressure of the pressure receiving chamber and the hydraulic pressure of the equilibrium chamber on both surfaces of the movable member through the first communication hole and the second communication hole formed in the wall portion of the storage space. In the fluid-filled type vibration damping device to which one of the A hollow-shaped shock absorber provided with a place is accommodated, and the shock absorber is brought into contact with the inner wall surface of the receiving space on the pressure receiving chamber side wall surface and the equilibrium chamber side wall inner surface; The movable member is accommodated in the internal space of the body, and the movable member is formed by communicating a first window formed in the buffer body with the first communication hole of the storage space. The fluid pressure of the pressure receiving chamber is exerted on one surface of the housing, and the second window portion formed in the buffer body is communicated with the second communication hole of the housing space, thereby moving the movable chamber. While the fluid pressure of the equilibrium chamber is exerted on the other surface of the member, a communication passage communicating with the first communication hole is formed in the wall portion of the buffer body on the pressure receiving chamber side, A short-circuit passage is formed, which includes the first communication hole and the communication passage, and always communicates the pressure receiving chamber and the accommodation space.

  According to the fluid-filled vibration isolator having the structure according to the first aspect as described above, the shock force when the movable member comes into contact with the wall inner surface of the accommodation space is reduced by providing the buffer. Thus, the contact sound is reduced. In addition, when the shock absorber is non-adhered in the housing space and the movable member comes into contact with a part of the wall portion of the shock absorber and an impact force is exerted, the other wall portion of the shock absorber is elastic. By being deformed, an energy attenuating action based on internal friction or the like is exhibited, and the contact sound is effectively prevented.

  In addition, a communication passage is formed in the buffer body, and the pressure receiving chamber and the accommodation space are always communicated with each other through a short-circuit passage that includes the first communication hole and the communication passage. Therefore, when the internal pressure of the pressure receiving chamber is greatly reduced and the movable member is separated from the second window portion, the pressure receiving chamber and the equilibrium chamber are communicated with each other through the short-circuit path, and fluid flows into the pressure receiving chamber. The pressure drop in the pressure receiving chamber is quickly reduced or eliminated. As a result, the generation of abnormal noise due to cavitation that becomes a problem when the pressure in the pressure receiving chamber is significantly reduced is prevented.

  In such a structure for preventing cavitation noise (short-circuit mechanism between the pressure receiving chamber and the equilibrium chamber), the first communication hole formed in the partition member is used in order to obtain the hydraulic pressure absorbing action by the movable member. Occurrence of cavitation noise can be prevented without requiring special processing of the member.

  According to a second aspect of the present invention, in the fluid-filled vibration isolator described in the first aspect, the buffer body includes a wall inner surface on the pressure receiving chamber side and a wall inner surface on the equilibrium chamber side of the housing space. And a pair of opposing plate portions disposed in contact with each other, and a pair of side plate portions connecting the pair of opposing plate portions, and the pressure receiving chamber The communication path formed in the opposing plate portion on the side extends in a direction orthogonal to the opposing direction of the pair of side plate portions and communicates with the first communication hole through the first window portion. It is.

  According to the second aspect, the buffer body is a band-shaped cylindrical body, so that it is elastically deformed relatively easily. Therefore, when the movable member is brought into contact with one counter plate portion, the input impact force efficiently elastically deforms the pair of side plate portions and the other counter plate portion, thereby making contact with the base plate based on the energy damping action. The sound reduction effect is advantageously exhibited.

  In addition, since the communication path communicates with the internal space of the buffer via a short path to reduce fluid friction and the like, fluid flows smoothly from the equilibrium chamber to the pressure receiving chamber when the pressure receiving chamber is greatly reduced in pressure. Thus, the negative pressure in the pressure receiving chamber is reduced or eliminated as quickly as possible. Thereby, the separation (cavitation) of the gas phase in the pressure receiving chamber is effectively suppressed, and the generation of abnormal noise due to cavitation is prevented.

  According to a third aspect of the present invention, in the fluid-filled vibration isolator described in the first or second aspect, the shock absorber is disposed separately from the inner surface of the peripheral wall of the housing space, and a gap is formed. The communication path is formed and communicated with the gap.

  According to the third aspect, since the buffer body is separated from the inner surface of the peripheral wall of the housing space, the buffer body can be easily elastically deformed without being restrained by the inner surface of the peripheral wall of the housing space. Arranged in a manner. Therefore, the effect of reducing the contact hitting sound based on the internal friction of the buffer body is more efficiently exhibited, and the quietness is improved.

  Further, the communication path is communicated with a gap formed between the buffer body and the inner surface of the peripheral wall of the housing space, so that the pressure receiving chamber and the housing are accommodated by the short-circuit path regardless of the position of the movable member in the internal space. The communication with the empty space is stably maintained. Therefore, when a significant pressure drop occurs in the pressure receiving chamber where cavitation noise is a problem, the negative pressure relaxation action due to fluid flow through the short-circuit path is stably exhibited, and the generation of noise is prevented.

  According to a fourth aspect of the present invention, in the fluid-filled vibration isolator described in any one of the first to third aspects, the communication path formed in the shock absorber is located on the pressure receiving chamber side. Thus, a defining means for defining the orientation of the buffer in the accommodation space is provided.

  According to the fourth aspect, when the buffer body is disposed in the accommodation space, the direction of the buffer body is defined by the defining means, so that the buffer body can be prevented from being attached in the wrong direction. Thus, for example, it is possible to avoid problems such as the communication path being positioned on the equilibrium chamber side. As a result, it is possible to easily and stably obtain the target vibration-proof performance and the effect of preventing cavitation noise.

  According to a fifth aspect of the present invention, in the fluid-filled vibration isolator described in the fourth aspect, the partition member is provided in the housing space from the wall portion on the equilibrium chamber side toward the pressure receiving chamber side. A protruding locking projection is provided, and a locking hole is formed in the wall of the buffer body on the side of the equilibrium chamber, and the locking projection is inserted into the locking hole to thereby The defining means and the positioning means for positioning the buffer with respect to the partition member are configured.

  According to the fifth aspect, since the shock absorber is positioned within the accommodation space by the positioning means, it is possible to prevent the displacement effect of the shock absorber from adversely affecting the abutting sound and the reduction effect of cavitation noise. be able to. Furthermore, the locking projection protrudes from the wall portion on the equilibrium chamber side of the housing space toward the pressure receiving chamber side, and the locking hole is formed on the wall portion on the equilibrium chamber side of the buffer body. By inserting the buffer body into the accommodation space so that the buffer body is inserted through the locking hole, the buffer body is arranged in the correct orientation.

  In addition, the positioning means and the defining means are realized with a simple structure in which the locking projections provided on the partition member are inserted into the locking holes provided on the buffer body, and the structure is complicated and the number of parts is reduced. Is prevented from increasing.

  According to the present invention, since the hollow buffer is accommodated in the accommodation space and the movable member is disposed in the internal space, the movable member comes into contact with the inner surface of the wall of the accommodation space. In addition, the contact sound is reduced by the energy damping action based on the internal friction of the buffer body. In addition, a short circuit passage is formed including a communication path provided in the shock absorber, and when the internal pressure of the pressure receiving chamber is greatly reduced, the pressure receiving chamber and the equilibrium chamber are communicated with each other through the short circuit passage. Since the pressure drop in the chamber is quickly relieved, the generation of abnormal noise due to cavitation is prevented. In addition, since the short-circuit passage is formed using the first communication hole, it is not necessary to form a special hole in the partition member, and the fluid-filled vibration isolator having the short-circuit passage is provided. Can be easily manufactured.

It is a longitudinal cross-sectional view which shows the engine mount as the 1st Embodiment of this invention, Comprising: The figure corresponded in the II cross section of FIG. It is another longitudinal cross-sectional view of the engine mount shown by FIG. 1, Comprising: The figure corresponded in the II-II cross section of FIG. III-III sectional drawing of FIG. The perspective view of the shock absorbing rubber which comprises the engine mount shown by FIG. The top view of the shock absorbing rubber shown by FIG. The front view of the shock absorbing rubber shown by FIG. The bottom view of the shock absorbing rubber shown by FIG. FIG. 2 is a longitudinal sectional view showing an enlarged main part of the engine mount shown in FIG. 1 and showing a state where an excessive negative pressure is applied to a pressure receiving chamber. The graph which shows the measurement result of the transmission load exerted on the 2nd attachment member. The longitudinal cross-sectional view which expands and shows the principal part of the engine mount as the 2nd Embodiment of this invention. The longitudinal cross-sectional view which expands and shows the principal part of the engine mount as the 3rd Embodiment of this invention. The perspective view of the shock absorbing rubber which comprises the engine mount shown by FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 3 show an engine mount 10 for an automobile as a first embodiment of a fluid-filled vibration isolator constructed according to the present invention. The engine mount 10 has a structure in which a first attachment member 12 and a second attachment member 14 are elastically connected by a main rubber elastic body 16, and the first attachment member 12 is attached to a power unit (not shown). The second attachment member 14 is attached to a vehicle body (not shown). In the following description, the vertical direction means the vertical direction in FIG. 1 in principle.

  More specifically, the first mounting member 12 is a high-rigidity member formed of iron, aluminum alloy or the like, and has a generally circular block shape with a small diameter as a whole, and the upper portion has a substantially cylindrical shape. And has a substantially truncated cone shape in the opposite direction in which the lower portion gradually decreases in diameter toward the lower side. Further, the first mounting member 12 is formed with a bolt hole 18 extending vertically on the central axis and opening on the upper surface, and a thread is formed on the inner peripheral surface.

  The second mounting member 14 is a highly rigid member formed of the same material as the first mounting member 12 and has a thin cylindrical shape with a large diameter. In addition, a constricted portion 20 having a groove shape that opens to the outer peripheral side is provided at the upper end portion of the second mounting member 14, and the flange portion 22 protrudes from the upper end of the constricted portion 20 toward the outer peripheral side. Yes.

  Then, the first mounting member 12 and the second mounting member 14 are arranged such that the first mounting member 12 is spaced above the second mounting member 14 on the same central axis, and the first mounting member 12 12 and the second mounting member 14 are elastically connected by a main rubber elastic body 16. The main rubber elastic body 16 has a thick, large-diameter, generally frustoconical shape. The first attachment member 12 is vulcanized and bonded to the end portion on the small diameter side, and the end portion on the large diameter side. The constricted portion 20 of the second attachment member 14 is overlapped and vulcanized and bonded to the outer peripheral surface. In the present embodiment, the main rubber elastic body 16 is formed as an integrally vulcanized molded product including the first mounting member 12 and the second mounting member 14.

  Furthermore, a large-diameter recess 24 is formed in the main rubber elastic body 16. The large-diameter recess 24 is a recess having a substantially mortar shape in the opposite direction that opens to the large-diameter side end face of the main rubber elastic body 16, and is formed in the central portion in the radial direction of the main rubber elastic body 16.

  Furthermore, a seal rubber layer 26 extends from the outer peripheral side of the large-diameter recess 24 in the main rubber elastic body 16. The seal rubber layer 26 is a rubber elastic body having a thin-walled and large-diameter substantially cylindrical shape, and is integrally formed with the main rubber elastic body 16 and fixed to the inner peripheral surface of the second mounting member 14.

  A flexible film 28 is attached to the integrally vulcanized molded product of the main rubber elastic body 16. The flexible film 28 is a rubber film having a thin disk shape or a circular dome shape, and has sufficient slackness in the axial direction. Further, an annular fixing portion 30 is integrally formed at the outer peripheral end portion of the flexible film 28, and the outer peripheral surface of the fixing portion 30 is vulcanized and bonded to the inner peripheral surface of the annular fixing member 32.

  Then, the fixing member 32 is inserted into the lower opening of the second mounting member 14, and the second mounting member 14 is subjected to diameter reduction processing such as an eight-way drawing, whereby the fixing member 32 is Fit on the mounting member 14, the flexible membrane 28 is disposed to close the lower opening of the second mounting member 14. A seal rubber layer 26 is interposed between the second mounting member 14 and the fixing member 32, and the second mounting member 14 and the fixing member 32 are fixed in a fluid tight manner.

  By attaching the flexible membrane 28 to the integrally vulcanized molded product of the main rubber elastic body 16 in this way, the space between the axially opposed surfaces of the main rubber elastic body 16 and the flexible membrane 28 is limited to the external space. Thus, a fluid chamber 34 is formed which is sealed and sealed with an incompressible fluid. The incompressible fluid sealed in the fluid chamber 34 is not particularly limited, and for example, water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixture thereof can be used. Further, in order to efficiently obtain a vibration isolation effect based on the fluid flow action described later, it is desirable to employ a low viscosity fluid of 0.1 Pa · s or less.

  A partition member 36 is accommodated in the fluid chamber 34. The partition member 36 has a thick, substantially disk shape as a whole, and includes an upper partition member 38 and a lower partition member 40.

  The upper partition member 38 has a substantially disk shape, and a central recess 42 that opens upward is formed in the central portion in the radial direction so that the volume of the pressure receiving chamber 66 described later can be efficiently secured. It has become. Further, a first communication hole 44 penetrating vertically is formed in the central portion of the bottom wall of the central recess 42. The first communication hole 44 has a substantially rectangular shape when viewed in the axial direction, and a pair of first communication holes 44 and 44 are provided at a predetermined distance in the short side direction. A plurality of upper fitting holes 46 are formed through the outer peripheral portion of the bottom wall portion of the central recess 42 at equal intervals on the periphery.

  Further, an upper groove 48 is formed at the outer peripheral end portion of the upper partition member 38 while opening to the outer peripheral surface and extending in a circumferential direction with a predetermined length, and one end portion of the upper groove 48 is radially inward. It extends and communicates with the central recess 42, and the other end opens to the lower surface.

  The lower partition member 40 has a substantially disk shape with a thick central portion, and a thin flange-like portion 50 projects from the lower end on the outer peripheral side thereof. The flange-shaped portion 50 extends with a predetermined length less than one circumference in the circumferential direction, and one end in the circumferential direction is an inclined portion that gradually becomes thicker toward the outer side in the circumferential direction, and the other The end portion opens downward in the axial direction. Furthermore, between the both ends of the flange-shaped part 50 in the circumferential direction, partition walls having substantially the same axial thickness as the central part are provided. In addition, a plurality of lower fitting holes (not shown) are formed at equal intervals on the circumference in the thick central portion.

  In addition, an accommodation recess 56 that opens upward is formed in the radial center portion of the lower partition member 40. The housing recess 56 has a substantially rectangular shape when viewed in the axial direction, and an insertion pin 58 as a locking projection protrudes upward from one side of the bottom wall in the long side direction. The insertion pin 58 has a substantially cylindrical shape with a small diameter, and in the present embodiment, the corner of the protruding tip portion is chamfered so that the protruding tip portion is reduced in diameter toward the tip side. ing.

  Further, a pair of second communication holes 60, 60 are formed through the bottom wall portion of the housing recess 56. The second communication hole 60 has a substantially same rectangular cross section as that of the first communication hole 44 and extends up and down. Like the first communication hole 44, a pair is provided at a predetermined distance in the short side direction. Yes. The second communication hole 60 is provided such that the long side direction thereof substantially coincides with the short side direction of the housing recess 56. In the combined state of the upper and lower partition members 38 and 40, which will be described later, The long side direction of the communication hole 44 and the long side direction of the second communication hole 60 substantially coincide.

  The upper partition member 38 and the lower partition member 40 are stacked one above the other, and a pin is press-fitted or a screw is screwed into the upper fitting hole 46 and the lower fitting hole that are positioned relative to each other. For example, they are fixed to each other. In addition, the lower side wall portion of the upper groove 48 of the upper partition member 38 is disposed to face the flange-like portion 50 of the lower partition member 40 so as to be spaced apart upward, thereby opening to the outer peripheral side and extending in the circumferential direction. A groove is formed, and the concave groove and the upper groove 48 are communicated with each other at the end in the circumferential direction, so that a circumferential groove 62 extending in a spiral shape with a length of less than two laps in the circumferential direction is formed. . Further, the opening of the housing recess 56 of the lower partition member 40 is covered with the upper partition member 38, so that a housing space 64 is formed between the upper and lower partition members 38, 40. The first communication hole 44 is formed through the upper wall portion of the accommodation space 64, and the second communication hole 60 is formed through the lower wall portion of the accommodation space 64.

  The partition member 36 having such a structure is accommodated in the fluid chamber 34 and extends in the direction perpendicular to the axis, and the outer peripheral end is supported by the second mounting member 14. As a result, the fluid chamber 34 is divided into two parts up and down across the partition member 36. Above the partition member 36, a part of the wall portion is constituted by the main rubber elastic body 16, and the internal pressure is applied when vibration is input. A pressure receiving chamber 66 is formed in which fluctuations are induced. On the other hand, below the partition member 36, a part of the wall portion is formed of the flexible film 28, and an equilibrium chamber 68 is formed in which volume change is easily allowed by deformation of the flexible film 28. ing. The pressure receiving chamber 66 and the equilibrium chamber 68 are filled with the above-described incompressible fluid.

  Further, the outer peripheral surface of the partition member 36 is overlapped with the second mounting member 14 via the seal rubber layer 26, so that the outer peripheral opening of the peripheral groove 62 is covered with the second mounting member 14 in a fluid-tight manner. Thus, a tunnel-like flow path extending in the circumferential direction is formed. One end in the circumferential direction of the tunnel-shaped flow path communicates with the pressure receiving chamber 66, and the other end in the circumferential direction communicates with the equilibrium chamber 68, whereby the pressure receiving chamber 66 and the equilibrium chamber 68 communicate with each other. An orifice passage 70 is formed using the circumferential groove 62. In addition, the orifice passage 70 adjusts the ratio (A / L) of the passage cross-sectional area (A) and the passage length (L) while taking into account the wall spring rigidity of the pressure receiving chamber 66 and the equilibrium chamber 68. Is tuned to a low frequency of about 10 Hz.

  Further, a buffer rubber 72 as a buffer body is accommodated in the accommodation space 64. As shown in FIGS. 4 to 7, the buffer rubber 72 is a hollow structure formed of a rubber elastic body. In the present embodiment, the buffer rubber 72 has a substantially rectangular shape when viewed in the axial direction, and is short. It is set as the substantially strip | belt-shaped cylindrical body provided with the internal space 74 penetrated in a side direction (up-down direction in FIG. 5).

  More specifically, the shock absorbing rubber 72 includes a pair of opposing plate portions 76a and 76b and a pair of side plate portions 78a and 78b that connect the pair of opposing plate portions 76a and 76b together. It has a substantially band-shaped cylindrical body.

  The pair of opposing plate portions 76a and 76b are plate-like bodies that have substantially rectangular shapes that correspond to each other when viewed in the axial direction, and are arranged to face each other with a predetermined distance therebetween in the vertical direction. In addition, a pair of first window portions 80, 80 are formed in the opposing plate portion 76a, and a pair of second window portions 82, 82 are formed in the opposing plate portion 76b. The first window portion 80 and the second window portion 82 are through-holes having substantially the same rectangular cross section, and a pair is formed adjacent to each other with a predetermined distance in the short side direction. The long side direction of the first window portion 80 is the short side direction of the counter plate portion 76a, and the long side direction of the second window portion 82 is the short side direction of the counter plate portion 76b. .

  Further, an insertion hole 84 as a locking hole is formed on the outer side in the short side direction of the pair of second window portions 82 and 82 in the opposing plate portion 76b. The insertion hole 84 is a hole penetrating vertically with a small-diameter circular cross section substantially corresponding to the insertion pin 58, and one insertion hole 84 corresponds to the insertion pin 58 with respect to the opposing plate portion 76 b of the buffer rubber 72. Is formed.

  In addition, a pair of side plate portions 78a and 78b are integrally formed at both ends in the long side direction of the pair of opposing plate portions 76a and 76b, and the pair of opposing plate portions 76a and 76b are a pair of side plate portions 78a and 78b. Are connected to each other. The pair of opposing plate portions 76a and 76b are connected to each other by the pair of side plate portions 78a and 78b, thereby forming a band-shaped cylindrical buffer rubber 72 and a pair of opposing plate portions 76a and 76b. An internal space 74 surrounded by a pair of side plate portions 78a and 78b is formed.

  The shock absorbing rubber 72 having such a structure is inserted into the receiving recess 56 of the lower partition member 40 without being bonded. The buffer rubber 72 is accommodated in the accommodating space 64 by the upper partition member 38 being superimposed and fixed on the lower partition member 40. The cushioning rubber 72 disposed in the accommodation space 64 is overlapped with the opposing plate portion 76a in contact with the inner surface of the upper wall of the accommodation space 64 in a non-adhesive manner, and the inner surface of the upper wall of the accommodation space 64 is opposed to the opposing plate. In addition to being covered with the portion 76a, the opposing plate portion 76b is superimposed on the inner surface of the upper wall of the accommodation space 64 in a non-adhesive manner, and the inner surface of the lower wall of the accommodation space 64 is covered with the opposing plate portion 76b. ing.

  The buffer rubber 72 is disposed at a predetermined distance from the inner surface of the peripheral wall of the housing space 64, and extends between the buffer rubber 72 and the inner surface of the peripheral wall of the housing space 64 over the entire circumference. A continuous gap 86 is formed.

  Further, when the buffer rubber 72 is inserted into the housing recess 56, the insertion pin 58 formed integrally with the lower partition member 40 is inserted into the insertion hole 84 of the buffer rubber 72, so that the insertion pin 58 is inserted into the buffer rubber 72. The counter plate 76b is inserted so as to penetrate vertically. As a result, a positioning means for positioning the buffer rubber 72 with respect to the partition member 36 in the accommodation space 64 by abutment locking between the outer peripheral surface of the insertion pin 58 and the inner peripheral surface of the insertion hole 84 is configured. Yes. Furthermore, since the insertion hole 84 is formed only on one side in the longitudinal direction of the opposing plate portion 76b, the buffer rubber 72 is inserted into the accommodation recess 56 in a predetermined manner by inserting the insertion pin 58 into the insertion hole 84. It is arranged in the direction, and thus the defining means in this embodiment is configured. Note that the insertion pin 58 is easily inserted into the insertion hole 84 by chamfering the corner of the protruding tip of the insertion pin 58.

  In addition, the first window portion 80 of the buffer rubber 72 is positioned with respect to the first communication hole 44 of the upper partition member 38 and communicated with each other, and the second window portion 82 of the buffer rubber 72 is positioned below. They are positioned with respect to the second communication hole 60 of the partition member 40 and communicate with each other. As a result, the fluid flow path 90 that allows the pressure receiving chamber 66 and the equilibrium chamber 68 to communicate with each other includes the first and second communication holes 44 and 60, the first and second window portions 80 and 82, and the accommodation space. 64 and an internal space 74.

  A movable plate 92 as a movable member is disposed on the fluid flow path 90. The movable plate 92 is a rectangular plate-shaped member formed of a rubber elastic body, synthetic resin, metal, or the like, and is formed separately from the buffer rubber 72. By being accommodated and disposed, it is disposed in the accommodation space 64. Further, as shown by the broken lines in FIG. 3, the movable plate 92 includes the first window portions 80 and 80 and the second window portion 82 in the long side direction and the short side direction of the opposing plate portions 76a and 76b. , 82 extends outside the outer ends. Further, the movable plate 92 is formed in the short side direction of the opposing plate portions 76a and 76b with the same or smaller dimension as the length of the short sides of the opposing plate portions 76a and 76b. A gap 94 is formed between the inner surface of the housing space 64 and the inner peripheral wall.

  The movable plate 92 is accommodated in the internal space 74 of the buffer rubber 72 so as to expand in a direction substantially perpendicular to the axis. Even if the movable plate 92 is displaced in the plane direction (direction perpendicular to the thickness direction) in the internal space 74, the outer peripheral ends thereof are the first window portions 80, 80 and the second window portions 82, The first window portions 80 and 80 and the second window portions 82 and 82 are formed in a size that can be held in a state of being located outside of the movable plate 92 in the axial projection. They are overlapping.

  In addition, the movable plate 92 is disposed so as to spread substantially perpendicular to the fluid flow path 90 extending in the axial direction, and the first communication hole 44 and the first window portion are formed on the upper surface of the movable plate 92. The pressure of the pressure receiving chamber 66 is applied through 80, and the pressure of the equilibrium chamber 68 is applied to the lower surface of the movable plate 92 through the second communication hole 60 and the second window portion 82. Thereby, the movable plate 92 is displaced up and down in the internal space 74 based on the relative pressure fluctuation between the pressure receiving chamber 66 and the equilibrium chamber 68.

  When medium frequency small amplitude vibration corresponding to idling vibration is input, the movable plate 92 is slightly displaced vertically within the internal space 74 so that the hydraulic pressure is transmitted between the pressure receiving chamber 66 and the equilibrium chamber 68. It has become. On the other hand, when the low frequency large amplitude vibration corresponding to the engine shake is input, the movable plate 92 blocks either the first window portion 80 or the second window portion 82 to block the fluid flow path 90. Transmission of hydraulic pressure through the fluid flow path 90 is prevented. In short, in the present embodiment, the hydraulic pressure transmission mechanism that transmits the hydraulic pressure of the pressure receiving chamber 66 to the equilibrium chamber 68 when the medium frequency small amplitude vibration is input includes the movable plate 92. In the present embodiment, the tuning frequency of the fluid flow path 90 is set to a medium frequency range corresponding to idling vibration, but can also be set to a high frequency range corresponding to traveling noise and the like.

  Therefore, in the engine mount 10 of the present embodiment, a communication path 96 is formed in the buffer rubber 72. As shown in FIGS. 4 and 5, the communication path 96 is formed in the opposing plate portion 76 a of the buffer rubber 72, and the short side of the opposing plate portion 76 a from the opening edge of the first window portion 80. It extends in a direction (a direction that is substantially orthogonal to the axial direction and the opposing direction of the pair of side plate portions 78a and 78b) and has a notch shape that partially cuts the frame of the first window portion 80. As is apparent from the above description, one end of the communication path 96 is communicated with the first window 80, and the other end is one of the short side directions of the opposing plate 76a. Open to the end face.

  As shown in FIGS. 1 and 2, the buffer rubber 72 provided with such a communication path 96 is in a state where the opposing plate portion 76 a is superimposed on the wall inner surface of the housing space 64 on the pressure receiving chamber 66 side. It is arranged. In the state where the buffer rubber 72 is disposed in the accommodation space 64, as shown in FIG. 2, one end of the communication path 96 is directly or directly via the first window 80. While communicating with the first communication hole 44, the other end communicates with the accommodation space 64 (gap 86). As a result, a short-circuit passage 98 that allows the pressure receiving chamber 66 and the accommodation space 64 to communicate with each other is formed including the communication passage 96, the first window 80, and the first communication hole 44. Since the cushioning rubber 72 is disposed in the accommodation space 64 in a predetermined direction by the above-described defining means, the communication path 96 is positioned on the pressure receiving chamber 66 side.

  The short-circuit passage 98 always keeps the pressure receiving chamber 66 and the accommodation space 64 in communication. That is, as shown in FIG. 8, even when the movable plate 92 is positioned at the upper end in the internal space 74 and is in contact with the opposing plate portion 76a, the inner surfaces of the peripheral walls of the movable plate 92 and the accommodation space 64 are used. The short-circuit path 98 is held in a communicating state by the gap 94. Further, the second plate 82 is opened by separating the movable plate 92 from the counter plate 76 b, and the accommodation space 64 communicates with the equilibrium chamber 68 through the second window 82 and the second communication hole 60. Is done. As a result, the hydraulic pressure in the pressure receiving chamber 66 decreases relative to the hydraulic pressure in the equilibrium chamber 68 and the movable plate 92 is separated from the opposing plate portion 76b, whereby the pressure receiving chamber 66 and the equilibrium chamber 68 are short-circuited path 98. To communicate with each other.

  The engine mount 10 having such a structure is attached to the vehicle by attaching the first attachment member 12 to a power unit (not shown) and attaching the second attachment member 14 to a vehicle body (not shown). The power unit and the vehicle body are connected to each other in a vibration-proof manner.

  When medium frequency small amplitude vibration corresponding to idling vibration frequency is input in such a vehicle mounted state, the orifice passage 70 is anti-resonant due to vibration input having a frequency higher than the tuning frequency and is substantially cut off. On the other hand, based on the relative pressure fluctuation between the pressure receiving chamber 66 and the equilibrium chamber 68, the movable plate 92 is slightly displaced up and down in the internal space 74 without contacting the pair of opposing plate portions 76a and 76b. As a result, the fluid flow path 90 is maintained in a communicating state, and the hydraulic pressure in the pressure receiving chamber 66 is transmitted to the equilibrium chamber 68 through the fluid flow path 90, so that the hydraulic pressure absorbing action due to the volume change of the equilibrium chamber 68 is exhibited. As a result, the intended vibration isolation effect (vibration insulation effect) can be obtained. As is clear from the above description, the fluid pressure transmission mechanism of the present embodiment is configured by the fluid channel 90 in which the movable plate 92 is disposed on the channel.

  Further, when a low-frequency large-amplitude vibration of about 10 Hz corresponding to the engine shake is input, fluid flow through the orifice passage 70 is caused based on relative pressure fluctuation between the pressure receiving chamber 66 and the equilibrium chamber 68. As a result, the intended vibration isolation effect (high attenuation effect) is exhibited based on the fluid action such as the resonance action of the fluid.

  Note that when the low-frequency large-amplitude vibration is input, the amount of displacement of the movable plate 92 in the vertical direction increases, so that the movable plate 92 is pressed against the pair of opposed plate portions 76a and 76b and substantially restrained. . As a result, one of the first and second window portions 80 and 82 is closed by the movable plate 92 and the fluid flow path 90 is shut off, so that the hydraulic pressure in the pressure receiving chamber 66 passes through the fluid flow path 90 to the equilibrium chamber. Transmission to the 68 side is prevented. Therefore, fluctuations in the internal pressure of the pressure receiving chamber 66 are efficiently induced, and a large amount of fluid flowing through the orifice passage 70 can be secured, so that the vibration isolation effect based on the fluid flow action is effectively exhibited. . In short, in the hydraulic pressure transmission mechanism according to the present embodiment, the fluid plate 90 is switched between communication and blocking by the movable plate 92, so that the hydraulic pressure transmission by the hydraulic pressure transmission mechanism between the pressure receiving chamber 66 and the equilibrium chamber 68 is performed. The presence or absence of can be switched. Further, in this embodiment, since the insertion pin 58 is provided on the outer peripheral side of the movable plate 92, the displacement amount of the movable plate 92 in the direction perpendicular to the axis is limited by the insertion pin 58, so that the relatively small size is achieved. The movable plate 92 can reliably block the first and second window portions 80 and 82.

  Here, the impact force generated when the movable plate 92 contacts the inner surfaces of the upper and lower walls of the accommodation space 64 is absorbed by the buffer rubber 72. That is, when the movable plate 92 comes into contact with the upper wall inner surface of the accommodation space 64 via the opposing plate portion 76a, the impact energy at the time of contact input to the opposing plate portion 76a is converted into a pair of side plate portions 78a, It is transmitted to the opposing plate part 76b through 78b. At that time, since the pair of side plate portions 78a and 78b and the counter plate portion 76b are slightly deformed by the input impact energy, the impact is based on the internal friction between the counter plate portion 76b and the pair of side plate portions 78a and 78b. Energy is converted into thermal energy. Thereby, the impact energy transmitted to the partition member 36 through the buffer rubber 72 is reduced, and the hitting sound caused by the impact energy can be reduced or avoided. When the movable plate 92 abuts against the inner surface of the lower wall of the accommodation space 64 via the counter plate portion 76b, the impact energy input to the counter plate portion 76b is opposed to the pair of side plate portions 78a and 78b. By being transmitted to the plate portion 76a, the same energy attenuating action is exhibited, and the occurrence of a hitting sound is prevented.

  Further, since the pair of side plate portions 78a and 78b are separated from the inner surface of the peripheral wall of the housing space 64, minute deformation of the pair of side plate portions 78a and 78b is also effectively generated, and the pair of opposed plate portions 76a and 76a, Efficient transmission of impact energy between 76b is realized, and the energy attenuating action in the pair of side plate portions 78a and 78b is also effectively exhibited. In addition, in the present embodiment, the insertion rubber pin 72 is inserted into the insertion hole 84 so that the buffer rubber 72 is positioned in the accommodation space 64, and the pair of side plate portions 78 a and 78 b and the peripheral wall of the accommodation space 64. Since the gap between the inner surface and the inner surface is maintained, the above effects can be stably obtained.

  On the other hand, if a shocking large load is input between the first mounting member 12 and the second mounting member 14 due to the automobile overcoming the step, the hydraulic pressure in the pressure receiving chamber 66 is significantly reduced. As shown in FIG. 8, the movable plate 92 is displaced to the upper end in the internal space 74 and comes into contact with the opposing plate portion 76 a, so that the first window portion 80 is blocked by the movable plate 92. In this case, a communication passage 96 is provided in the buffer rubber 72, and the communication passage 96 communicates with the accommodation space 64, the first window 80, and the first communication hole 44, so that the accommodation space 64 is formed. The pressure receiving chamber 66 communicates with the pressure receiving chamber 66 through a short-circuit passage 98.

  Further, since the movable plate 92 is located at the upper end and is separated from the counter plate portion 76 b, the equilibrium chamber 68 is communicated with the accommodation space 64 through the second window portion 82 and the second communication hole 60. . As a result, the pressure receiving chamber 66 and the equilibrium chamber 68 communicate with each other through the short-circuit passage 98, and the fluid flows from the equilibrium chamber 68 toward the pressure receiving chamber 66 as indicated by arrows in FIG. As a result, the pressure drop in the pressure receiving chamber 66 is reduced or eliminated as quickly as possible, and abnormal noise due to cavitation is prevented.

  Moreover, in the engine mount 10 of the present embodiment, the pressure receiving chamber 66 and the equilibrium chamber 68 are in communication with each other by forming the short-circuit passage 98 using the first communication hole 44 of the partition member 36. Therefore, it is not necessary to specially form a hole for short-circuiting the pressure receiving chamber 66 and the equilibrium chamber 68 in the partition member 36, and the engine mount 10 including the short-circuit mechanism can be easily formed.

  Further, when the pressure in the pressure receiving chamber 66 decreases, the pressure receiving chamber 66 and the equilibrium chamber 68 are short-circuited through the short-circuit passage 98 and the second window 82, and when the pressure in the pressure receiving chamber 66 increases, Since the movable plate 92 blocks the second window portion 82, a short circuit between the pressure receiving chamber 66 and the equilibrium chamber 68 is prevented. Therefore, when a positive pressure is applied to the pressure receiving chamber 66 where cavitation is not a problem, the internal pressure fluctuation of the pressure receiving chamber 66 is effectively induced, and a vibration isolation effect based on the fluid flow through the orifice passage 70 can be efficiently obtained. it can.

  Further, a gap 86 is provided between the buffer rubber 72 and the inner surface of the peripheral wall of the accommodation space 64, and the end of the communication path 96 is communicated with the gap 86. Accordingly, even when the movable plate 92 is displaced in the short side direction toward the communication path 96 forming side (left side in FIG. 8) and the gap 94 is eliminated, the communication path 96 is communicated with the internal space 74 by the gap 86. The Therefore, the short-circuit passage 98 is maintained in a communication state regardless of the position of the movable plate 92, and the intended effect of reducing the abnormal cavitation noise can be stably obtained.

  Furthermore, the shock absorbing rubber 72 is a strip-shaped cylindrical body that opens in the short side direction, and the communication path 96 opens in the end surface in the short side direction of the counter plate portion 76a. Thereby, the communication path 96 is communicated with the internal space 74 at a short distance, and the fluid flow is smoothly generated. Therefore, the negative pressure in the pressure receiving chamber 66 is reduced or eliminated more quickly, and the target noise reduction effect is effectively exhibited.

  Further, since the insertion hole 84 is formed only in the opposing plate portion 76 b of the buffer rubber 72, the insertion pin 58 protruding from the bottom wall of the accommodation space 64 is inserted into the insertion hole 84, so that the buffer rubber 72 The direction in the accommodation space 64 is specified, and the communication path 96 is positioned on the pressure receiving chamber 66 side. Thereby, when the buffer rubber 72 is fitted into the receiving recess 56, a defining means for preventing the buffer rubber 72 from being disposed in the wrong direction is configured, and the buffer rubber 72 can be easily used in an intended mode. Can be arranged. Moreover, in the present embodiment, the defining means as described above is configured by using the insertion pin 58 and the insertion hole 84 for constituting the positioning means for positioning the buffer rubber 72 in the accommodation space 64. The defining means can be provided by a simple structure.

  By the way, in the engine mount 10 (example) according to the present embodiment, the transmission load transmitted to the second mounting member 14 is reduced as compared with an engine mount (comparative example) that does not include the communication path 96. This is also apparent from the measurement result graph shown in FIG. In FIG. 9, the measurement result of the example is indicated by a solid line, and the measurement result of the comparative example is indicated by a broken line. Furthermore, in FIG. 9, the main body input displacement (the relative approach displacement amount of the first mounting member 12 and the second mounting member 14) is indicated by a one-dot chain line. Further, the engine mount of the comparative example has the same structure as the engine mount 10 of the embodiment except that the communication path 96 is not formed in the buffer rubber 72.

  According to FIG. 9, in the comparative example, when the first attachment member 12 and the second attachment member 14 are relatively greatly displaced in the separation direction, the internal pressure of the pressure receiving chamber 66 is significantly reduced. A large load is transmitted to the mounting member 14. On the other hand, in the embodiment, even if the first attachment member 12 and the second attachment member 14 are largely displaced, the transmission load to the second attachment member 14 is kept small. The transmission load to the second mounting member 14 is caused by a shock wave generated when the cavitation bubble disappears. According to the measurement result, the cavitation noise is higher in the example than in the comparative example. Has been reduced.

  FIG. 10 shows an engine mount as a second embodiment of the fluid filled type vibration damping device according to the present invention in an enlarged vertical sectional view of a main part. In the following description, members and portions that are substantially the same as those in the first embodiment are denoted by the same reference numerals in the drawings, and the description thereof is omitted.

  That is, in the engine mount of the present embodiment, the shock absorbing rubber 100 as a shock absorber is disposed in the housing space 64 of the partition member 36. The buffer rubber 100 has substantially the same shape as the buffer rubber 72 of the first embodiment, and is larger than the buffer rubber 72 in the short side direction. Thereby, the buffer rubber 100 is in contact with the inner surface of the peripheral wall of the housing space 64 in the short side direction, and in this embodiment, the buffer rubber 72 and the inner surface of the peripheral wall of the housing space 64 in the first embodiment. The gap 86 formed between the two is not provided.

  On the other hand, the movable plate 92 is formed in substantially the same shape and size as in the first embodiment, and is smaller than the buffer rubber 100 in the short side direction. Thereby, a gap 94 is formed between the outer peripheral surface of the movable plate 92 and the inner surface of the peripheral wall of the accommodation space 64.

  Also in the engine mount of this embodiment, the short-circuit path 98 is formed using the communication path 96, the first window portion 80, and the first communication hole 44, and the short-circuit path 98 is formed by the gap 94. It communicates with the accommodation space 64 (internal space 74). In the state where the hydraulic pressure in the pressure receiving chamber 66 is significantly reduced and the movable plate 92 is in contact with the opposing plate portion 76b, the pressure receiving chamber 66 and the equilibrium chamber 68 are communicated with each other by the short-circuit passage 98. The negative pressure in the pressure receiving chamber 66 is quickly eliminated, and the generation of abnormal noise due to cavitation is prevented. Thus, in the present invention, it is not essential that a gap is formed between the buffer body and the inner surface of the peripheral wall of the housing space, and the buffer body is disposed in contact with the inner surface of the peripheral wall of the housing space. May be.

  In FIG. 11, an engine mount as a third embodiment of the fluid filled type vibration damping device according to the present invention is shown in an enlarged longitudinal sectional view of a main part. In this engine mount, a shock absorbing rubber 110 as a shock absorber is accommodated in the accommodating space 64 of the partition member 36.

  As shown in FIG. 12, the buffer rubber 110 includes a pair of opposing plate portions 76a and 76b and a pair of side plate portions 78a and 78b having substantially the same shape as the buffer rubber 72 of the first embodiment. In addition, a pair of first window portions 80, 80 are formed in the opposing plate portion 76a, and a pair of second window portions 82, 82 are formed in the opposing plate portion 76b.

  A communication path 112 is formed in the buffer rubber 110. The communication path 112 is formed in the frame portion of the first window portion 80 in the opposing plate portion 76a, and is formed in a concave groove shape that opens in the upper surface of the opposing plate portion 76a and extends in the short side direction. The end portion communicates with the first window portion 80, and the other end portion opens on the outer peripheral surface of the opposing plate portion 76a.

  The buffer rubber 110 is disposed in the accommodation space 64, and the opposing plate portion 76 a abuts against the inner wall surface of the accommodation space 64 on the pressure receiving chamber 66 side without adhesion, and the opposing plate portion 76 b. Is in contact with the inner surface of the balance chamber 68 of the accommodation space 64 in a non-adhesive manner. In addition, the communication path 112 is partly covered with the upper partition member 38 to form a tunnel shape, and the first window 80 and the gap 86 are always in communication.

  As a result, the hydraulic pressure in the pressure receiving chamber 66 is greatly reduced by the input of a shocking large load, the movable plate 92 is displaced toward the pressure receiving chamber 66, and the first window 80 is blocked by the movable plate 92. At the same time, when the second window 82 is opened to the communication state, the pressure receiving chamber 66 and the equilibrium chamber 68 are communicated with each other through the short-circuit passage 114 including the communication passage 112. As a result, the pressure drop in the pressure receiving chamber 66 is mitigated, and abnormal noise due to cavitation is prevented.

  As described above, the communication passage formed in the buffer body is not necessarily a communication passage 96 having a notch shape that cuts the frame portion of the first window 80 as shown in the first and second embodiments. Without being limited thereto, a groove-like communication path 112 as shown in the present embodiment can also be adopted. In the case of adopting a groove-shaped communication path, the groove may be provided on the upper surface of the opposing plate portion 76a so as to communicate with the internal space 74 through the gap 86 and the gap 94. An opening may be provided in the lower surface of 76 a and communicated with the internal space 74 through the gap 86.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, in the above embodiment, only one communication path is formed, but a plurality of communication paths may be formed.

  Further, the movable member is not limited to the movable plate 92 having a shape substantially corresponding to the planar shape of the accommodation space 64 as shown in the above-described embodiment. For example, the movable member is opened to the outer peripheral surface of the movable plate 92 and is thick. By forming the concave groove extending in the vertical direction, the pressure receiving chamber 66 and the accommodation space 64 by the short-circuit passage 98 can be stably held in communication.

  In the embodiment, the first and second communication holes 44 and 60 formed in the partition member 36 and the first and second window portions 80 and 82 formed in the buffer rubber 72 are both provided. Although the pair is provided one by one, the numbers of the first and second communication holes 44 and 60 and the first and second window portions 80 and 82 are not particularly limited.

  Moreover, in the said embodiment, although the band-shaped cylindrical buffer rubber 72 is illustrated as a buffer body, the buffer body should just be a hollow shape, for example, one opening part in the said buffer rubber 72 is. It may be in the form of a closed bag.

  Further, the movable member is not limited to the movable plate 92 independent of the partition member 36 and the buffer rubber 72. For example, the movable member is integrally formed with the buffer rubber 72 and protrudes from the side plate portion 78a to the internal space 74. A movable film or the like that protrudes from the opening of the buffer rubber 72 to both sides in the short side direction and is supported at both ends by the partition member 36 can also be adopted as the movable member.

  Further, as the defining means, in addition to the structure using the insertion pin 58 and the insertion hole 84 exemplified in the above embodiment, the vertical direction of the buffer rubber 72 can be changed when the buffer rubber 72 is assembled into the receiving recess 56. Various defined structures may be employed. For example, in the buffer rubber 72, at least the surfaces of the side plate portions 78a and 78b on the outer side in the opposite direction are inclined so as to gradually approach each other toward the balance chamber 68, or a step is formed in the intermediate portion in the height direction of the side plate portions 78a and 78b. Is provided so that the length dimension of the opposing plate portion 76a in the long side direction is larger than the length dimension of the opposing plate portion 76b in the long side direction. Correspondingly, the peripheral wall portions on both sides in the long side direction of the accommodating recess 56 are also inclined surfaces or stepped surfaces corresponding to the inclined surfaces or steps on the outer side of the side plate portions 78a and 78b, thereby facing the counter plate portion 76a. Due to the size difference from the plate portion 76b, the cushioning rubber 72 is prevented from being fitted in the receiving recess 56 in the upside down direction, and the orientation of the cushioning rubber 72 is determined so that the communication path 96 is positioned on the pressure receiving chamber 66 side. A defining means may be configured.

  In addition, a protruding portion that protrudes outward in the opposing direction is formed with respect to the opposing plate portions 76a and 76b, and the opposing plate portions 76a and 76b partially abut against the inner wall surface of the housing space 64 at the protruding portion. Anyway. According to this, at the time of contact of the movable plate 92, the opposing plate portions 76a and 76b are more likely to be elastically deformed, and the effect of reducing the contact sound can be advantageously obtained.

  Furthermore, by forming inward protrusions that protrude inward in the opposing direction with respect to the opposing plate portions 76a and 76b, the initial contact area of the movable plate 92 with respect to the opposing plate portions 76a and 76b can be reduced and contact can be made. It is also possible to reduce the hitting sound.

  The present invention is not only applied to the engine mount, but can be suitably applied to various fluid-filled vibration isolator devices including a body mount and a member mount. Further, the scope of application of the present invention is not limited to a fluid-filled vibration isolator for automobiles, and is also applicable to a fluid-filled vibration isolator used for other than automobiles, such as motorcycles, railway vehicles, and industrial vehicles. Can be done.

10: engine mount (fluid-filled vibration isolator), 12: first mounting member, 14: second mounting member, 16: main rubber elastic body, 28: flexible membrane, 36: partition member, 44: First communication hole 58: Insertion pin (locking projection) 60: Second communication hole 64: Storage space 66: Pressure receiving chamber 68: Equilibrium chamber 70: Orifice passage 72, 100, 110 : Buffer rubber (buffer body), 74: internal space, 76: counter plate portion, 78: side plate portion, 80: first window portion, 82: second window portion, 84: locking hole, 86: gap , 92: movable plate (movable member), 96, 112: communication path, 98, 114: short circuit path

Claims (5)

The first mounting member and the second mounting member are elastically connected by the main rubber elastic body, and a part of the wall portion sandwiches the partition member supported by the second mounting member. The pressure receiving chambers and the equilibrium chambers in which a part of the wall portion is made of a flexible membrane are formed, and the pressure receiving chambers and the equilibrium chambers are filled with incompressible fluid, and these pressure receiving chambers And an equilibrium passage are formed in the partition member, and an accommodation space is formed in the partition member, and a movable member is accommodated in the accommodation space. A fluid-filled type in which one of the hydraulic pressure of the pressure receiving chamber and the hydraulic pressure of the equilibrium chamber is exerted on both surfaces of the movable member through a first communication hole and a second communication hole formed in the wall portion In the vibration isolator,
A hollow buffer body having an internal space is accommodated and disposed in the housing space, and the buffer body contacts the inner wall surface on the pressure receiving chamber side and the inner wall surface on the equilibrium chamber side of the housing space. The movable member is accommodated in the internal space of the buffer body, and a first window formed in the buffer body is in the first communication hole of the storage space. The fluid pressure of the pressure receiving chamber is exerted on one surface of the movable member by the communication, and the second window formed in the buffer body is the second communication hole of the housing space. While the fluid pressure of the equilibrium chamber is exerted on the other surface of the movable member by communicating with
A communication passage that communicates with the first communication hole is formed in a wall portion of the shock absorber on the pressure receiving chamber side, and includes the first communication hole and the communication passage. A fluid-filled type vibration damping device, wherein a short-circuit passage that always communicates with the accommodation space is formed.   A pair of opposing plate portions disposed so as to abut each of the pressure receiving chamber side wall inner surface and the equilibrium chamber side wall inner surface of the accommodating space; and the pair of opposing plate portions. An integral strip-shaped cylindrical body having a pair of side plate portions to be connected, and the communication passage formed in the opposing plate portion on the pressure receiving chamber side is orthogonal to the opposing direction of the pair of side plate portions. The fluid filled type vibration damping device according to claim 1, wherein the fluid filled type vibration damping device extends in a direction to be communicated with the first communication hole via the first window portion.   3. The fluid-filled type according to claim 1, wherein the buffer body is spaced from the inner surface of the peripheral wall of the housing space to form a gap, and the communication path communicates with the gap. Anti-vibration device.   The regulation means which prescribes | regulates the direction in the said accommodation space of this buffer is provided so that the said communicating path formed in the said buffer may be located in the said pressure receiving chamber side. The fluid-filled vibration isolator according to the item.   The partition member is provided with a locking projection that protrudes from the wall portion on the equilibrium chamber side toward the pressure receiving chamber side in the accommodation space, and on the wall portion on the equilibrium chamber side of the buffer body. A locking hole is formed, and the defining means and a positioning means for positioning the buffer relative to the partition member are configured by inserting the locking protrusion into the locking hole. 4. The fluid-filled vibration isolator according to 4.

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