JP2014085003A - Fluid sealed type vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid sealed type vibration control device with a novel structure that is made compact in an axial direction and can sufficiently and stably obtain fluid tightness at the part where a partition member and a flexible film are fitted to a second fitting member.SOLUTION: A cylindrical peripheral wall part 52 of a fixed member 50 fixed to a flexible film 48 is inserted radially between a second fitting member 14 and a partition member 68, and the second fitting member 14 is reduced in diameter so as to seal the part between the second fitting member 14 and cylindrical peripheral wall part 52 with an outer peripheral seal rubber 42. An inner peripheral seal rubber 58 which covers an inner peripheral surface of the cylindrical peripheral wall part 52 is provided with a tapered inner peripheral surface 62 which increases in diameter axially toward one side, and the partition member 68 is provided with a tapered outer peripheral surface 76 which increases in diameter axially toward the one side. While the overlapped tapered inner peripheral surface 62 and tapered outer peripheral surface 76 are brought into close contact with each other and the part between the cylindrical peripheral wall part 52 and partition member 68 is sealed with the inner peripheral seal rubber 58, the fixed member 50 is positioned axially with the second fitting member 14.

Description

  The present invention relates to a vibration isolator used for, for example, an automobile engine mount and the like, and more particularly, to a fluid filled type vibration isolator utilizing a vibration isolating effect based on a flow action of an incompressible fluid sealed inside. Is.

  Conventionally, an anti-vibration device is known as a type of anti-vibration coupling body or anti-vibration support body that is interposed between members constituting a vibration transmission system and anti-vibration-couples the members to each other. Furthermore, based on the resonance action of the incompressible fluid enclosed in the interior, a fluid-filled vibration isolator that has a particularly excellent anti-vibration effect in a specific frequency range has been proposed. It is applied to engine mounts. As shown in, for example, Japanese Patent Application Laid-Open No. 2012-13163 (Patent Document 1), the fluid-filled vibration isolator includes a first attachment member attached to one member constituting a vibration transmission system, It has a structure in which a cylindrical second attachment member attached to the other member constituting the vibration transmission system is elastically connected by a main rubber elastic body. Further, on both sides of the partition member inserted and supported by the second mounting member, a pressure receiving chamber in which a part of the wall part is constituted by a main rubber elastic body and a part of the wall part are flexible. An equilibrium chamber made of a membrane is formed, and the pressure receiving chamber and the equilibrium chamber are connected to each other by an orifice passage.

  By the way, the flexible membrane that constitutes a part of the wall portion of the equilibrium chamber shrinks the second mounting member in a state where the fixing member fixed to the outer peripheral end portion is inserted into the lower end portion of the second mounting member. The diameter is attached so as to close the lower opening of the second attachment member.

  However, in the structure described in Patent Document 1, since the fixing member is overlapped with the partition member in the axial direction and disposed below, the axial dimension in the outer peripheral portion of the vibration isolator increases. There was a problem. In particular, a fluid-tight seal is required between the fixing member and the second mounting member, and it is necessary to ensure a sufficient axial dimension of the fixing member in order to obtain sufficient sealing performance. For this reason, in the structure of Patent Document 1, it is difficult to avoid an increase in the axial dimension.

  International publication WO2010 / 126059 (patent document 2) discloses a structure in which a fixing member is disposed on the outer peripheral side of a partition member. However, in such a structure, in order to fluid-tightly seal between the fixing member and the partition member, a passage inner cylinder portion protruding in the axial direction is provided on the fixing member, and the passage inner cylinder portion is used as the partition member. On the other hand, the rubber layer needs to be in close contact with each other, and there is a possibility that the axial dimension is not sufficiently reduced. In addition, since the members are sealed by the close contact in the radial direction by the diameter reduction processing of the second mounting member, there is a possibility that individual differences may occur in the sealing performance due to variations in the dimensional tolerance of the members and variations in the diameter reduction deformation. there were.

JP2012-13163A International Publication No. WO2010 / 126059

  The present invention has been made in the background of the above-mentioned circumstances, and the problem to be solved is that the size of the axial member is reduced and the partition member for the second attachment member and the seal of the attachment portion of the flexible membrane are provided. An object of the present invention is to provide a fluid-filled vibration isolator having a novel structure capable of sufficiently and stably obtaining performance.

  That is, in the first aspect of the present invention, the first mounting member and the cylindrical second mounting member are elastically connected by the main rubber elastic body, and are inserted into the second mounting member and supported. A part of the wall part forms a pressure receiving chamber composed of the main rubber elastic body on one side in the axial direction across the partition member, and a part of the wall part is allowed on the other side in the axial direction across the partition member. A fluid-filled vibration proofing that forms an equilibrium chamber composed of a flexible membrane, encloses an incompressible fluid in the pressure receiving chamber and the equilibrium chamber, and forms an orifice passage that connects the pressure receiving chamber and the equilibrium chamber to each other In the apparatus, a fixing member is fixed to the outer peripheral end portion of the flexible membrane, and a cylindrical peripheral wall portion provided on the fixing member is inserted between the second mounting member and the partition member in the radial direction. An outer peripheral seal rubber is interposed between the second mounting member and the cylindrical peripheral wall portion. The second mounting member and the cylindrical peripheral wall portion are sealed fluid-tightly by the outer peripheral seal rubber, while the inner peripheral seal rubber is fixed to the inner peripheral surface of the cylindrical peripheral wall portion. The inner peripheral surface of the inner peripheral seal rubber is provided with a tapered inner peripheral surface having a large diameter toward one side in the axial direction, and the outer peripheral surface of the partition member is increased toward the one side in the axial direction. A tapered outer peripheral surface having a diameter is provided, and the tapered inner peripheral surface and the tapered outer peripheral surface are overlapped, and the tapered inner peripheral surface and the tapered outer peripheral surface are in close contact with each other, The fixing member is positioned in the axial direction by the second mounting member in a state in which the space between the partition members is fluid-tightly sealed by the inner peripheral seal rubber.

  According to such a fluid-filled vibration isolator described in the first aspect, the cylindrical peripheral wall portion of the fixing member is inserted between the second mounting member and the partition member in the radial direction. In order to secure the supporting portion of the member, it is not necessary to project the second mounting member below the partition member so that the size can be reduced in the axial direction.

  Furthermore, the space between the second mounting member and the cylindrical peripheral wall portion is fluid-tightly sealed with an outer peripheral seal rubber, and the space between the partition member and the cylindrical peripheral wall portion is fluid-tightly sealed with an inner peripheral seal rubber. . Therefore, in the structure in which the cylindrical peripheral wall portion is inserted between the second mounting member and the partition member, the fluid tightness between the members is sufficiently ensured on both the inner peripheral side and the outer peripheral side of the cylindrical peripheral wall portion, Problems due to leakage of incompressible fluid and short circuit are prevented.

  According to a second aspect of the present invention, in the fluid-filled vibration isolator described in the first aspect, an annular bottom wall that protrudes toward the inner peripheral side at the other axial end of the cylindrical peripheral wall portion of the fixing member. The annular bottom wall portion is overlapped with the partition member in the axial direction, and a bottom seal rubber is interposed between the annular bottom wall portion and the partition member, and the annular bottom wall portion And the partition member are fluid-tightly sealed by the bottom seal rubber, and the fixing member is positioned in the axial direction by the second mounting member.

  According to the second aspect, between the fixing member and the partition member, a sealing structure by an inner peripheral seal rubber between the overlapping surfaces in the radial direction and a sealing structure by the bottom seal rubber between the overlapping surfaces in the axial direction Is provided. Therefore, it is possible to more effectively prevent the incompressible fluid from being short-circuited between the overlapping surfaces of the fixing member and the partition member, and to effectively obtain the target vibration isolation performance with excellent reliability. it can.

  According to a third aspect of the present invention, in the fluid-filled vibration isolator described in the second aspect, the bottom seal rubber is fixed to the annular bottom wall portion, and the bottom seal rubber is attached to the partition member. A seal lip projecting toward the surface is provided.

  According to the third aspect, by providing the bottom seal rubber with the seal lip, the sealing performance by the bottom seal rubber is improved, and a short circuit of the fluid is more effectively prevented between the fixing member and the partition member. Moreover, since the bottom seal rubber is fixed to the annular bottom wall portion, for example, the bottom seal rubber can be integrally formed with the flexible film to reduce the number of parts.

  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 seal rubber extends from the outer peripheral end of the main rubber elastic body toward the other axial direction. A layer covering the inner peripheral surface of the second mounting member, and the outer circumferential seal rubber having a thin and large diameter on the other side in the axial direction relative to the step provided in the middle in the axial direction of the seal rubber layer. An annular lip portion that protrudes in the other axial direction and protrudes against the inner peripheral seal rubber in the axial direction is provided at the inner circumferential end portion of the inner circumferential end portion.

  According to the fourth aspect, the outer peripheral seal rubber is a part of the seal rubber layer integrally formed with the main rubber elastic body, and the number of parts and molds can be reduced. In addition, the annular lip portion provided in the seal rubber layer is brought into contact with the inner peripheral seal rubber in the axial direction, so that a further sealing structure is formed, and the fluid tightness between the members can be further enhanced. .

  According to a fifth aspect of the present invention, in the fluid-filled vibration isolator described in any one of the first to fourth aspects, the second mounting member has a locking portion protruding toward the inner peripheral side. The fixing member is positioned in the axial direction with respect to the second mounting member by locking the locking portion to the fixing member.

  According to the fifth aspect, the axial disengagement and the positional deviation of the fixing member with respect to the second mounting member are more effectively prevented by providing the locking portion, and the tapered inner peripheral surface and the tapered outer periphery are prevented. The sealed state due to the close contact of the surfaces is stably maintained.

  According to a sixth aspect of the present invention, in the fluid-filled vibration isolator described in the fifth aspect, a locking projection that protrudes to the outer peripheral side is provided at one end in the axial direction of the cylindrical peripheral wall portion. The locking projection overlaps the locking portion of the second mounting member in the axial projection.

  According to the sixth aspect, the locking protrusion is locked in the axial direction with respect to the locking portion, thereby preventing the fixing member from coming off from the second mounting member. Note that the term “locking protrusions locked in the locking portion” here does not only refer to the case where the locking protrusions are directly abutted and locked, but the case where the locking protrusions are indirectly locked via the outer peripheral seal rubber. including.

  According to the present invention, since the cylindrical peripheral wall portion of the fixing member is inserted between the second mounting member and the partition member in the radial direction, downsizing in the axial direction is realized. Further, the outer peripheral seal rubber is narrowed between the cylindrical peripheral wall portion and the second mounting member by the diameter reduction of the second mounting member, and the space between the cylindrical peripheral wall portion and the second mounting member is sealed. In addition, the taper inner peripheral surface of the inner peripheral seal rubber and the taper outer peripheral surface of the partition member are in close contact with each other, and the space between the cylindrical peripheral wall portion and the partition member is sealed. Positioned in the axial direction. Thereby, while realizing miniaturization in the axial direction, fluid tightness between the members is ensured, and deterioration of the vibration proof performance due to leakage of a sealed fluid or a short circuit is prevented.

1 is a longitudinal sectional view showing an engine mount as one embodiment of the present invention. The longitudinal cross-sectional view which shows the integral vulcanization molded product of the main body rubber elastic body which comprises the engine mount shown by FIG. The longitudinal cross-sectional view which shows the integral vulcanization molded product of the flexible membrane which comprises the engine mount shown by FIG. The fragmentary sectional view which expands and shows the principal part of the integral vulcanization molded product of the flexible membrane shown in FIG. The longitudinal cross-sectional view of the partition member which comprises the engine mount shown by FIG. The fragmentary sectional view which expands and shows the principal part of the engine mount shown by FIG.

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

  FIG. 1 shows an engine mount 10 for an automobile as an embodiment of a fluid filled type vibration damping device having a structure according to the present invention. The engine mount 10 has a structure in which a first mounting member 12 and a cylindrical second mounting member 14 are elastically connected by a main rubber elastic body 16. In the following description, the vertical direction means the vertical direction in FIG. 1 that is the axial direction of the second mounting member 14 and is the main vibration input direction in principle.

  More specifically, the first mounting member 12 is a highly rigid member having a substantially columnar shape, and a flange portion 18 protruding toward the outer peripheral side is integrally formed at the upper end portion. Further, the first mounting member 12 is formed with a screw hole 20 opened on the upper surface extending vertically on the central axis. An inner bracket (not shown) is attached to the first attachment member 12 by an attachment bolt that is screwed into the screw hole 20, and the first attachment member 12 is not shown via the inner bracket. It can be attached to the power unit.

  The second mounting member 14 is a highly rigid member similar to the first mounting member 12 and has a thin cylindrical shape with a large diameter. Further, the second mounting member 14 has an annular step portion at an axially intermediate portion, the upper side sandwiching the step portion is a large-diameter fixed cylinder portion 24, and the step portion is sandwiched therebetween. The lower side is a small diameter fitting cylinder portion 26. An outer bracket (not shown) is externally fitted to the second attachment member 14, and the second attachment member 14 is attached to a vehicle body (not shown) via the outer bracket.

  The first mounting member 12 is disposed on the same central axis in the upper opening of the second mounting member 14, and the first mounting member 12 and the second mounting member 14 are the main rubber elastic body 16. It is elastically connected by. As shown in FIG. 2, the main rubber elastic body 16 has a thick and large-diameter substantially truncated cone shape, and the end portion on the small-diameter side is vulcanized and bonded to the first mounting member 12. In addition, the outer peripheral surface of the end portion on the large diameter side is vulcanized and bonded to the inner peripheral surface of the second mounting member 14. As shown in FIG. 2, the main rubber elastic body 16 is formed as a first integral vulcanized product 28 including a first attachment member 12 and a second attachment member 14.

  Further, a central recess 30 is formed in the central portion of the main rubber elastic body 16 so as to open to the axial end surface (lower surface) on the large diameter side. The central recess 30 is a recess having a reverse mortar shape that expands downward.

  Further, a seal rubber layer 34 is integrally formed on the outer peripheral portion of the main rubber elastic body 16. The sealing rubber layer 34 has a large-diameter, generally cylindrical shape, protrudes downward from the outer peripheral side of the opening of the central recess 30, and covers and fixes the inner peripheral surface of the second mounting member 14. Has been. The inner peripheral surface of the seal rubber layer 34 is larger in diameter than the inner peripheral surface of the central recess 30, and an annular contact is made between the inner peripheral surface of the seal rubber layer 34 and the inner peripheral surface of the central recess 30. A surface 36 is formed.

  Furthermore, a step 38 is provided in an axially intermediate portion of the seal rubber layer 34, and a thick orifice fitting portion 40 is formed on the upper side in the axial direction with the step 38 interposed therebetween. The lower side in the direction is a thin-walled outer peripheral seal rubber 42 having an increased inner diameter. Furthermore, an annular lip portion 44 that protrudes downward is formed at the inner peripheral end of the step 38 in the seal rubber layer 34. The annular lip portion 44 extends with a substantially constant cross-sectional shape over the entire circumference, is formed with a protruding dimension that does not reach the lower end of the outer peripheral seal rubber 42, and is predetermined on the inner peripheral side with respect to the outer peripheral seal rubber 42. Are arranged at a distance of. As a result, an annular insertion groove 46 that opens downward is formed between the outer peripheral seal rubber 42 and the annular lip 44 in the radial direction.

  A flexible film 48 is attached to the first integrally vulcanized molded product 28 having such a structure. As shown in FIG. 3, the flexible film 48 is a thin circular rubber film formed with sufficient slack. A fixing member 50 is fixed to the outer peripheral end of the flexible film 48. The fixing member 50 is integrally provided with a substantially cylindrical cylindrical peripheral wall portion 52 and a substantially annular plate-shaped annular bottom wall portion 54 that protrudes inward from the lower end of the cylindrical peripheral wall portion 52. As a whole, it has a substantially L-shaped vertical cross-sectional shape and extends in a circumferential annular shape. Further, the upper end portion of the cylindrical peripheral wall portion 52 is bent toward the outer peripheral side, and a locking projection 56 that protrudes toward the outer peripheral side is formed integrally with the upper end portion that is one end portion in the axial direction of the cylindrical peripheral wall portion 52. Has been. The outer peripheral end of the flexible membrane 48 is vulcanized and bonded to the inner peripheral end of the annular bottom wall portion 54, and the flexible membrane 48 includes a fixing member 50 as shown in FIG. The second integral vulcanized molded product 57 is formed.

  Further, as shown in FIG. 4, an inner peripheral seal rubber 58 and a bottom seal rubber 60 are fixed to the fixing member 50. The inner peripheral seal rubber 58 is a cylindrical rubber elastic body, and is vulcanized and bonded to the inner peripheral surface of the cylindrical peripheral wall portion 52 of the fixing member 50. Further, the inner peripheral surface of the inner peripheral seal rubber 58 is a tapered inner peripheral surface 62 having a large diameter toward one side in the axial direction (upper side in FIG. 4), and the inner peripheral seal rubber 58 gradually becomes thinner toward the upper side. It has become. In the present embodiment, the tapered inner peripheral surface 62 is inclined at a substantially constant inclination angle: θ in the longitudinal section (see FIG. 4).

  On the other hand, the bottom seal rubber 60 is a substantially annular plate-shaped rubber elastic body, and is vulcanized and bonded to the upper surface of the annular bottom wall portion 54 of the fixing member 50. Further, the bottom seal rubber 60 is integrally formed with a seal lip 64 projecting upward, and continuously extends over the entire circumference in a substantially constant semicircular cross section. In this embodiment, the inner peripheral seal rubber 58 and the bottom seal rubber 60 are integrally formed with the flexible film 48.

  The second integral vulcanized molded product 57 is attached to the first integral vulcanized molded product 28 by the fixing member 50 being inserted and fixed to the second mounting member 14 from below, The lower opening of the second attachment member 14 is closed with a flexible film 48. As a result, a fluid chamber 66 that is fluid-tightly separated from the outside is formed between the main rubber elastic body 16 and the flexible membrane 48 in the axial direction. An incompressible fluid is enclosed in the fluid chamber 66. Has been. The incompressible fluid sealed in the fluid chamber 66 is not particularly limited. For example, water, alkylene glycol, polyalkylene glycol, silicone oil, or a mixed solution thereof is preferably employed. The Furthermore, it is desirable to employ a low-viscosity fluid of 0.1 Pa · s or less in order to efficiently obtain a vibration isolation effect based on the fluid flow action. The incompressible fluid is sealed in the fluid chamber 66 by, for example, a water tank filled with the incompressible fluid in the assembling operation of the first integral vulcanized product 28 and the second integral vulcanized product 57. It can be easily realized by performing in.

  A partition member 68 is disposed in the fluid chamber 66. The partition member 68 is a substantially disk-shaped member formed of a metal such as a hard synthetic resin or an aluminum alloy. As shown in FIG. 5, the partition member 68 is open at the upper recess and the lower surface. The central portion in the radial direction is thinned by forming the lower recess, and the peripheral groove 74 is formed in the outer peripheral portion so as to open in the outer peripheral surface while extending in the circumferential direction. Furthermore, the lower end portion of the outer peripheral surface of the partition member 68 is a tapered outer peripheral surface 76 that gradually increases in diameter toward the upper side that is one side in the axial direction. In this embodiment, the taper outer peripheral surface 76 is inclined at a constant angle: θ substantially the same as the taper inner peripheral surface 62 in the longitudinal section, but the inclination angles of the taper inner peripheral surface 62 and the taper outer peripheral surface 76 are mutually different. It may be different. Further, the tapered inner peripheral surface 62 and the tapered outer peripheral surface 76 do not need to be inclined at a constant angle with respect to the axial direction, and the inclination angle may be gradually changed.

  As shown in FIG. 1, the partition member 68 is inserted and supported by the second mounting member 14, and is disposed so as to extend in the direction perpendicular to the axis in the fluid chamber 66. Thereby, the fluid chamber 66 is divided into two parts up and down across the partition member 68, and a part of the wall portion is constituted by the main rubber elastic body 16 on one side (upper side) in the axial direction across the partition member 68. In addition, a pressure receiving chamber 78 in which an internal pressure fluctuation is caused at the time of vibration input is formed, and a part of the wall portion is a flexible film 48 on the other side (lower side) in the axial direction across the partition member 68. Thus, an equilibrium chamber 80 in which volume change is easily allowed is formed. Needless to say, the pressure receiving chamber 78 and the equilibrium chamber 80 are filled with an incompressible fluid.

  Moreover, the outer peripheral opening part of the circumferential groove 74 formed in the partition member 68 is covered with the second mounting member 14 and closed fluid-tightly to form a tunnel-like flow path. The both ends of the tunnel-shaped flow path are connected to one of the pressure receiving chamber 78 and the equilibrium chamber 80 through the upper communication hole 82 and the lower communication hole 84, so that the pressure receiving chamber 78 and the equilibrium chamber 80 communicate with each other. A passage 86 is formed using the circumferential groove 74. The orifice passage 86 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 fluid chamber 66, so that the resonance frequency ( Tuning frequency) can be arbitrarily set. In this embodiment, the tuning frequency is set to a low frequency of about 10 Hz corresponding to engine shake.

  Here, as shown in FIGS. 1 and 6, the cylindrical peripheral wall 52 of the fixing member 50 is inserted between the second mounting member 14 and the partition member 68 in the radial direction, and the cylindrical peripheral wall The portion 52 is accommodated and arranged on the inner peripheral side of the second mounting member 14. Thereby, the enlargement in the axial direction in the outer peripheral portion of the engine mount 10 due to the downward protrusion of the fixing member 50 is avoided, and the engine mount 10 is made compact. As a result, interference with other members can be avoided especially when other members are arranged below the outer peripheral portion of the engine mount 10.

  Further, in the engine mount 10, the cylindrical peripheral wall portion 52 of the fixing member 50 is inserted between the second mounting member 14 and the partition member 68 in the radial direction. A sealing structure is provided on each peripheral side.

  That is, the space between the fixing member 50 and the second mounting member 14 is sealed in a fluid-tight manner, and leakage of the incompressible fluid to the outside is prevented. Specifically, the outer peripheral seal rubber 42 fixed to the inner peripheral surface of the second mounting member 14 is disposed on the outer peripheral side of the cylindrical peripheral wall portion 52 of the fixing member 50, and the second mounting member 14 has a reduced diameter. By being processed, it is in close contact with the outer peripheral surface of the cylindrical peripheral wall portion 52. Thereby, the space between the overlapping surfaces of the second mounting member 14 and the cylindrical peripheral wall portion 52 of the fixing member 50 is sealed fluid-tightly by the outer peripheral seal rubber 42. Note that the fixing member 50 is a highly rigid member, and the cylindrical peripheral wall portion 52 of the fixing member 50 is held in a shape with almost no deformation when the diameter of the second mounting member 14 is reduced. The sealing rubber 42 is sufficiently pressed against the cylindrical peripheral wall portion 52, and sealing performance is ensured.

  In addition, in this embodiment, the annular lip portion 44 provided in the seal rubber layer 34 is pressed against the inner peripheral seal rubber 58 in the axial direction to form an auxiliary sealing structure, and the outside of the sealed fluid Leakage is prevented with higher long-term reliability.

  Furthermore, the space between the fixing member 50 and the partition member 68 is also fluid-tightly sealed, so that the vibration-proof performance is prevented from being lowered due to a short circuit of the orifice passage 86. That is, as shown in FIG. 4, the inner peripheral seal rubber 58 fixed to the inner peripheral surface of the cylindrical peripheral wall portion 52 has its inner peripheral surface directed toward one side in the axial direction (the upper side in FIG. 4). The tapered inner peripheral surface 62 is gradually increased in diameter. On the other hand, as shown in FIG. 5, the outer peripheral surface of the lower portion of the partition member 68 is a tapered outer peripheral surface 76 that gradually increases in diameter toward one side in the axial direction (the lower side in FIG. 5). . Then, when the cylindrical peripheral wall portion 52 of the fixing member 50 is extrapolated to the lower part of the partition member 68, the tapered inner peripheral surface 62 of the inner peripheral seal rubber 58 and the tapered outer peripheral surface 76 of the partition member 68 are overlapped with each other. Yes. Further, by pushing the fixing member 50 to one side in the axial direction, the overlapped tapered inner peripheral surface 62 and the tapered outer peripheral surface 76 are brought into close contact with each other, and the radial direction between the partition member 68 and the fixing member 50 is the inner periphery. The seal rubber 58 is sealed in a fluid-tight manner. Then, the diameter of the second mounting member 14 is reduced in a state where the tapered inner peripheral surface 62 and the tapered outer peripheral surface 76 are in close contact with each other, and the fixing member 50 is positioned in the axial direction by the second mounting member 14. Thus, the sealed state by the close contact between the tapered inner peripheral surface 62 and the tapered outer peripheral surface 76 is stably maintained.

  In particular, in the present embodiment, the lower end portion of the second mounting member 14 is bent toward the inner peripheral side simultaneously with the diameter reduction process or in a separate process, and protrudes toward the inner peripheral side at the lower end portion of the second mounting member 14. A stop 88 is formed. The locking member 88 is overlapped and locked in the axial direction with respect to the fixing member 50, whereby the fixing member 50 is positioned in the axial direction with respect to the second mounting member 14. Further, when the locking portion 88 is formed, the fixing member 50 is pressed upward in the axial direction by the locking portion 88 so that the taper inner peripheral surface 62 and the taper outer peripheral surface 76 are brought into close contact with each other. 14 can also be positioned axially. In the present embodiment, in the state before the diameter reduction shown in FIG. 2, the lower end portion of the second mounting member 14 has a tapered shape in which the diameter is reduced downward in advance. By bend | folding to the surrounding side, the latching | locking part 88 is stably formed in a predetermined shape.

  Further, an annular bottom wall portion 54 of the fixing member 50 is overlapped in the axial direction from below on the outer peripheral portion of the partition member 68, and a bottom seal rubber 60 is interposed between the overlapping surfaces of the partition member 68 and the annular bottom wall portion 54. Is intervened. The annular bottom wall 54 is pressed against the partition member 68 in the axial direction via the bottom seal rubber 60, and the bottom seal rubber 60 allows fluid to flow between the overlapping surfaces of the annular bottom wall 54 and the partition member 68. The fixing member 50 is positioned in the axial direction with respect to the second mounting member 14 in a tightly sealed state. The outer peripheral end of the upper surface of the partition member 68 is in contact with the annular contact surface 36 of the main rubber elastic body 16, and an upward pressing force acts on the partition member 68 when the locking portion 88 is formed. However, since the upward displacement of the partition member 68 is limited, the bottom seal rubber 60 is sufficiently narrowed between the annular bottom wall portion 54 and the partition member 68 to ensure fluid tightness.

  In addition, in this embodiment, the seal lip 64 integrally formed with the bottom seal rubber 60 is provided so as to protrude toward the partition member 68, and the seal lip 64 is pressed against the lower surface of the partition member 68. The space between the annular bottom wall portion 54 and the partition member 68 is sealed to improve the sealing performance. However, the seal lip 64 is not essential, and a plate-like portion fixed so as to cover the annular bottom wall portion 54 of the bottom seal rubber 60 is directly pressed against the lower surface of the partition member 68 to form a sealing structure. May be. Further, the cross-sectional shape and the like of the seal lip 64 are not particularly limited.

  It should be noted that the orifice fitting portion 40 of the seal rubber layer 34 is interposed between the second mounting member 14 and the partition member 68 in the radial direction at the portion where the inner peripheral seal rubber 58 is displaced upward, and the second mounting member 14. The outer peripheral surface of the partition member 68 is pressed against the orifice fitting portion 40 by the diameter reduction processing, and the radial direction between the second mounting member 14 and the partition member 68 is sealed in a fluid-tight manner. As a result, a short circuit of the orifice passage 86 to the pressure receiving chamber 78 and the equilibrium chamber 80 is prevented over the entire length, and the intended vibration-proofing effect is stably exhibited.

  Thus, in the engine mount 10, a plurality of sealing structures are provided between the fixing member 50, the second mounting member 14, and the partition member 68. As a result, the incompressible fluid leaks out from the fluid chamber 66, or a short circuit occurs between the pressure receiving chamber 78 and the equilibrium chamber 80, so that the amount of fluid flowing through the orifice passage 86 is reduced, and the vibration proof performance. Can be avoided.

  Further, in the fixing member 50 of the present embodiment, a locking projection 56 that protrudes toward the outer peripheral side with respect to the upper end portion of the cylindrical peripheral wall portion 52 is integrally formed, and the locking projection 56 is formed on the second mounting member 14. The locking portion 88 and the axial projection overlap each other. Thereby, the downward detachment of the fixing member 50 with respect to the second mounting member 14 is more reliably prevented.

  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 fixing member 50 of the above-described embodiment, a structure including the annular bottom wall portion 54 at the lower end of the cylindrical peripheral wall portion 52 is illustrated, but the annular bottom wall portion 54 is not essential and may be omitted. .

  Further, the outer peripheral seal rubber 42 may be fixed to, for example, the cylindrical peripheral wall portion 52 of the fixing member 50, and in that case, it can be integrally formed with the flexible film 48. As is clear from this, the outer peripheral seal rubber 42 may be formed separately from the main rubber elastic body 16.

  Further, the bottom seal rubber 60 can be fixedly provided on the partition member 68, and may be formed separately from the flexible film 48. When the bottom seal rubber 60 is fixed to the partition member 68, the inner peripheral seal rubber 58 can be formed separately from the flexible film 48.

  Further, when the fixing member 50 is pressed upward by the locking portion 88 of the second mounting member 14, the tapered inner peripheral surface 62 and the tapered outer peripheral surface 76 are brought into close contact with each other, and the cylindrical peripheral wall portion 52 of the fixing member 50. And the partition member 68 may be sealed. However, for example, the diameter of the second mounting member 14 is reduced in a state where the fixing member 50 is previously pressed upward with a jig or the like and the tapered inner peripheral surface 62 and the tapered outer peripheral surface 76 are in close contact with each other. Accordingly, it is possible to position the fixing member 50 in the axial direction with respect to the second mounting member 14. As is clear from this, the locking portion 88 is not essential, and may be omitted if the fixing member 50 is positioned with respect to the second mounting member 14.

  Furthermore, the taper inner peripheral surface 62 and the taper outer peripheral surface 76 may be in close contact by relatively displacing the fixing member 50 and the partition member 68 in the axial direction. For example, the cylindrical peripheral wall portion 52 of the fixing member 50 Even if the fixing member 50 is positioned in the axial direction by the second mounting member 14 and is kept in close contact after being brought into close contact by being reduced in diameter in a state of being extrapolated to the partition member 68. good.

  In the above-described embodiment, the locking portion 88 extends to the lower side of the cylindrical peripheral wall portion 52 of the fixing member 50 so that the locking portion 88 can be directly contacted and locked to the fixing member 50. However, the locking portion 88 and the fixing member 50 may be indirectly locked via other members or the like. Specifically, for example, the locking portion 88 overlaps only with the locking projection 56 in the projection in the axial direction, and the locking portion 88 and the locking projection 56 are indirectly locked via the outer peripheral seal rubber 42. Thus, the fixing member 50 may be positioned in the axial direction by the second mounting member 14.

  The present invention is not necessarily applied only to a fluid-filled vibration isolator used as an engine mount, but can also be applied to a fluid-filled vibration isolator used as a subframe mount, body mount, differential mount, or the like. . Further, the scope of application of the present invention is not limited to a fluid-filled vibration isolator for automobiles, and the present invention is also suitably applied to a fluid-filled vibration isolator used for motorcycles, railway vehicles, and industrial vehicles. The

10: engine mount (fluid-filled vibration isolator), 12: first mounting member, 14: second mounting member, 16: main rubber elastic body, 34: seal rubber layer, 38: step, 42: outer peripheral seal rubber, 44: annular lip portion, 48: flexible membrane, 50: fixing member, 52: cylindrical peripheral wall portion, 54: annular bottom wall portion, 56: locking projection, 58: inner peripheral sealing rubber, 60: bottom sealing rubber, 62 : Tapered inner peripheral surface, 64: Seal lip, 68: Partition member, 76: Tapered outer peripheral surface, 78: Pressure receiving chamber, 80: Equilibrium chamber, 86: Orifice passage, 88: Locking portion

Claims (6)

The first mounting member and the cylindrical second mounting member are elastically connected to each other by a main rubber elastic body, and a wall is provided on one axial side with a partition member inserted and supported by the second mounting member interposed therebetween. A part of the part forms a pressure receiving chamber composed of the main rubber elastic body, and a part of the wall forms an equilibrium chamber composed of a flexible film on the other side in the axial direction across the partition member In addition, in the fluid-filled vibration isolator that encloses the incompressible fluid in the pressure receiving chamber and the equilibrium chamber and forms an orifice passage that communicates the pressure receiving chamber and the equilibrium chamber with each other,
A fixing member is fixed to the outer peripheral end of the flexible membrane, and a cylindrical peripheral wall provided on the fixing member is inserted between the second mounting member and the partition member in the radial direction. ,
An outer peripheral seal rubber is interposed between the second mounting member and the cylindrical peripheral wall portion, and a fluid-tight seal is provided between the second mounting member and the cylindrical peripheral wall portion by the outer peripheral seal rubber. ,
An inner peripheral seal rubber is fixed to the inner peripheral surface of the cylindrical peripheral wall portion, and a tapered inner peripheral surface having a large diameter toward one side in the axial direction is provided on the inner peripheral surface of the inner peripheral seal rubber. In addition, the outer peripheral surface of the partition member is provided with a tapered outer peripheral surface having a large diameter toward one side in the axial direction, and the tapered inner peripheral surface and the tapered outer peripheral surface are overlapped with each other. And the tapered outer peripheral surface are in close contact with each other, and the space between the cylindrical peripheral wall portion and the partition member is fluid-tightly sealed by the inner peripheral seal rubber, and the fixing member is fixed by the second mounting member. A fluid-filled vibration isolator characterized by being positioned in the axial direction.   An annular bottom wall portion projecting inward is integrally formed at the other axial end of the cylindrical peripheral wall portion of the fixing member, and the annular bottom wall portion is overlapped with the partition member in the axial direction. A bottom seal rubber is interposed between the annular bottom wall portion and the partition member, and the fixing member is in a state where the space between the annular bottom wall portion and the partition member is fluid-tightly sealed by the bottom seal rubber. The fluid-filled vibration isolator according to claim 1, wherein the fluid-filled vibration isolator is positioned in the axial direction by the second mounting member.   The fluid-filled vibration isolator according to claim 2, wherein the bottom seal rubber is fixed to the annular bottom wall portion, and the bottom seal rubber is provided with a seal lip protruding toward the partition member.   A seal rubber layer extending from the outer peripheral end of the main rubber elastic body toward the other in the axial direction covers the inner peripheral surface of the second mounting member, and is more axial than the step provided in the axial middle of the seal rubber layer. The other side in the direction is the outer peripheral seal rubber having a thin wall and a large diameter, and an annular lip portion is provided at the inner peripheral end of the step so as to protrude in the other axial direction and abut against the inner peripheral seal rubber in the axial direction. The fluid-filled vibration isolator according to any one of claims 1 to 3.   The second mounting member is provided with a locking portion protruding toward the inner peripheral side, and the locking member is locked to the fixing member so that the fixing member is fixed to the second mounting member. The fluid-filled vibration damping device according to claim 1, wherein the fluid-filled vibration damping device is positioned in the axial direction.   One end of the cylindrical peripheral wall portion in the axial direction is provided with a locking protrusion that protrudes to the outer peripheral side, and the locking protrusion is axially formed with respect to the locking portion of the second mounting member. The fluid-filled vibration isolator according to claim 5, which overlaps in projection.

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