JP2008045641A - Fluid filled type cylindrical vibration control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid filled type cylindrical vibration control device with a novel structure capable of improving efficiency of manufacturing work by reducing the number of components, and capable of stably providing an anticipated vibration control effect on the basis of sufficiently securing durability of a body rubber elastic body. <P>SOLUTION: A first stopper 58, protruding from an inner shaft member 12 toward an outer cylinder member 14 in a pressure receiving chamber 52, in a state wherein a circumferential center line of the pressure receiving chamber 52 passing through a center of the inner shaft member 12 is attached obliquely in a circumferential direction with respect to an input direction of a main load exerted in a shaft perpendicular direction on the inner shaft member 12 and the outer cylinder member 14, is provided such that it is deflected in an oblique direction of the circumferential center line of the pressure receiving chamber 52 with respect to an input direction line of the main load passing through the center of the inner shaft member 12, and in parallel with the input direction line of the main load. A second stopper 60 protruding from the inner shaft member 12 toward the outer cylinder member 14 in a penetration void 40 is provided on the input direction line of the main load. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fluid-filled cylindrical vibration isolator that obtains an anti-vibration effect based on the flow action or the like of an incompressible fluid enclosed therein, for example, an engine mount or subframe for an automobile. The present invention relates to a fluid-filled cylindrical vibration isolator that is applied to a mount, a body mount, a differential mount, a suspension bush, and the like.

  2. Description of the Related Art Conventionally, a fluid-filled cylindrical vibration isolator is known as a type of anti-vibration coupling body or anti-vibration support body interposed between members constituting a vibration transmission system. This fluid-filled cylindrical vibration isolator is provided with a main rubber elastic body between the inner shaft metal fittings and the outer cylinder metal fittings spaced apart on the outer peripheral side thereof in the direction perpendicular to the axis, and elastically supports them with the main rubber elastic material. It is a connected structure. In addition, a pressure receiving chamber to which vibration is input and an equilibrium chamber in which volume change is allowed are provided. Incompressible fluid is sealed in the pressure receiving chamber and the equilibrium chamber, and both chambers pass through the orifice passage. They are in communication with each other. In particular, the pressure receiving chamber extends in the circumferential direction around the central axis of the inner shaft metal fitting, and the wall portions on both sides in the circumferential direction are constituted by the main rubber elastic body, so that Pressure fluctuations are generated in the pressure receiving chamber based on the elastic deformation. In such a cylindrical vibration isolator, a vibration isolating effect is obtained by a fluid action such as a resonance action of a fluid that causes a relative pressure fluctuation in the pressure receiving chamber and the equilibrium chamber to flow through the orifice passage when vibration is input. Therefore, application to engine mounts, suspension bushes and the like for automobiles has been studied.

  By the way, when such a cylindrical vibration isolator is adopted as an engine mount for an automobile, one of the problems is a vibration in the circumferential direction with respect to the vertical direction between the axially opposed surfaces of the inner shaft bracket and the outer tube bracket. It may be input at an angle. For this reason, the pressure receiving chamber is formed between the axially opposed surfaces of the inner shaft metal fitting and the outer cylinder metal fitting so as to effectively obtain the vibration isolation effect by highly expressing the spring characteristics of both walls in the circumferential direction of the pressure receiving chamber against the vibration. In some cases, the circumferential wall walls are attached with the direction in which both wall portions extend in the direction of vibration input. As a result, the pressure receiving chamber is mounted with the circumferential center line inclined in the circumferential direction with respect to the vertical direction.

  Moreover, in the cylindrical vibration isolator employed in the above-described tilted-type automobile engine mount and the like, one of the problematic vibrations is a vibration in the bound / rebound direction (vertical direction). In order to obtain high damping performance, it is effective to provide a stopper member extending in the vertical direction between the inner shaft fitting and the outer cylinder fitting.

  However, in the vibration isolator mounted in such a manner that the circumferential center line of the pressure receiving chamber is inclined in the circumferential direction with respect to the vertical direction, the vertically extending stopper member extends from the inner shaft bracket to the outer cylinder bracket. If the protrusion is provided, the base end portion of the stopper member is biased on either one of the circumferential wall portions of the pressure receiving chamber, and the elastic deformation of the wall portion may be restrained by the stopper member. It was. As a result, an excessive stress is generated in the main rubber elastic body, and there is a problem that it is difficult to ensure sufficient durability.

  In order to cope with the above-described problem, for example, as shown in Patent Document 1 (Japanese Patent Laid-Open No. 10-38012) and Patent Document 2 (Japanese Patent Laid-Open No. 10-252812), the stopper member is attached to the outer member. It is conceivable to project from the cylindrical metal fitting side toward the inner shaft metal fitting. By doing so, the elastic deformation of the main rubber elastic body is not restrained by the stopper member, and it is considered that the durability is advantageously ensured.

  However, in the vibration isolator having the structure, since the stopper member is not integrally provided on the inner shaft member side to which the main rubber elastic body is fixed, the number of parts is increased, so that the number of assembling steps is increased and the manufacturing is performed. There was a problem that became complicated.

Japanese Patent Laid-Open No. 10-38012 Japanese Patent Laid-Open No. 10-252812

  Here, the present invention has been made in the background as described above, and the problem to be solved is that the efficiency of manufacturing work can be improved by reducing the number of parts, It is an object of the present invention to provide a fluid-filled cylindrical vibration isolator having a novel structure that can stably obtain the desired vibration isolating effect based on sufficiently ensuring the durability of the main rubber elastic body.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  That is, the feature of the present invention is that the outer cylinder member is disposed separately on the outer peripheral side of the inner shaft member, and the inner shaft member and the outer are disposed on one side in a direction perpendicular to the axis across the inner shaft member. The cylindrical member is connected by a main rubber elastic body, and a through space is formed on the other side perpendicular to the axis across the inner shaft member so as to penetrate between the inner shaft member and the outer cylindrical member in the axial direction. On the other hand, a pressure receiving chamber is formed inside the main rubber elastic body, and an equilibrium chamber having a wall formed of a flexible membrane is formed in the through space, and the pressure receiving chamber and the equilibrium chamber are formed. In a fluid-filled cylindrical vibration isolator in which an incompressible fluid is sealed in and communicated with each other through an orifice passage, in an input direction of a main load exerted perpendicularly to the inner shaft member and the outer cylinder member In contrast, the center of the inner shaft member The circumferential center line of the pressure-receiving chamber that passes through is inclined and mounted in the circumferential direction, and under such a mounting state, a first stopper that protrudes from the inner shaft member toward the outer cylinder member in the pressure-receiving chamber, It deviates in the inclination direction of the circumferential center line of the pressure receiving chamber with respect to the input direction line of the main load passing through the center of the inner shaft member, and projects parallel to the input direction line of the main load passing through the center of the inner shaft member. On the other hand, the second stopper that protrudes from the inner shaft member toward the outer cylinder member in the through space is protruded on the input line of the main load passing through the center of the inner shaft member.

  In such a fluid-filled cylindrical vibration isolator having a structure according to the present invention, the first stopper and the second stopper constituting the stopper mechanism for inputting the main load are both provided on the inner shaft member side. As a result, the outer cylinder member is merely disposed on the outer peripheral side of the inner shaft member, and is provided between the two members in the direction perpendicular to the axis. Therefore, since the increase in the number of parts and the extension of the manufacturing process due to the retrofitting of the stopper between the inner shaft member and the outer cylinder member can be suppressed, the manufacturing efficiency can be advantageously improved.

  In particular, the circumferential center line of the pressure-receiving chamber that passes through the center of the inner shaft member is mounted so as to be inclined in the circumferential direction with respect to the input direction of the main load. In addition, the main rubber elastic body spreads on both sides in the circumferential direction of the pressure receiving chamber, and the damping performance against the input in a direction different from the main load can be advantageously exhibited.

  In this state, the first stopper that protrudes into the pressure receiving chamber is biased in the inclination direction of the circumferential center line of the pressure receiving chamber with respect to the input direction line of the main load passing through the center of the inner shaft member. Will be. As a result, the base end portion of the first stopper projecting from the inner shaft member is positioned on the substantially center line in the circumferential direction of the pressure receiving chamber, and the main rubber constituting the wall portions on both sides in the circumferential direction of the pressure receiving chamber Provided to avoid elastic bodies. As a result, restraint of the main rubber elastic body by the first stopper is suppressed, and excessive stress is locally generated in the main rubber elastic body. It can be done.

  In addition, the base end portion of the first stopper is positioned on the substantially center line in the circumferential direction of the pressure receiving chamber, and the first stopper projects in parallel to the input direction line of the main load passing through the center of the inner shaft member. By being provided, the respective volumes on both sides in the circumferential direction across the first stopper in the pressure receiving chamber are substantially the same. That is, an unintended constricted portion is not formed in the pressure receiving chamber due to the fact that the volume of one side in the circumferential direction across the first stopper of the pressure receiving chamber is greatly different from the other volume. For this reason, it is avoided that a trouble occurs in the fluid flow action of the pressure receiving chamber due to the narrowed portion, and the vibration isolation effect based on the fluid flow action is stably obtained.

  In the fluid-filled cylindrical vibration isolator according to the present invention, the through space is a pressure receiving chamber with respect to the input direction line of the main load passing through the center of the inner shaft member in the circumferential direction around the central axis of the inner shaft member. A structure in which the equilibrium chamber is positioned on one side in the circumferential direction of the second stopper by forming the equilibrium chamber on the same side as the inclination direction of the circumferential center line is suitably employed. .

  According to such a structure, it is possible to effectively secure a space for forming the equilibrium chamber in the through space while avoiding interference with the second stopper of the equilibrium chamber, and to set the volume of the equilibrium chamber large. . In particular, since the equilibrium chamber is formed only on one side in the circumferential direction of the second stopper of the through space, the structure of the equilibrium chamber is simplified as compared with the case where it is formed on both sides.

  That is, in this structure, since the circumferential center line of the pressure receiving chamber is inclined in the circumferential direction with respect to the input direction of the main load, the circumferential center line of the through space facing the pressure receiving chamber in the direction perpendicular to the axis is also As a result, the projection direction of the second stopper extending in the input direction is inclined in the circumferential direction with respect to the circumferential center line of the through space, so that the second stopper A large space is created on the opposite side to the protruding direction. By utilizing this large space, the equilibrium chamber can be set with a simple structure and a large volume.

  Further, in the fluid-filled cylindrical vibration isolator according to the present invention, the intermediate sleeve is disposed apart from the outer peripheral side of the inner shaft member, and the intermediate sleeve is fixed to the outer peripheral surface of the main rubber elastic body. A first pocket portion is formed in the rubber elastic body, a first window portion is formed in the intermediate sleeve, a first pocket portion is opened on the outer peripheral surface through the first window portion, and an outer cylinder is formed in the intermediate sleeve. A structure in which the pressure receiving chamber is formed by the member being fitted and fixed and the first window portion being covered is suitably employed.

  According to this structure, the pressure receiving chamber in which the incompressible fluid is enclosed is easily formed. Further, for example, by interposing a seal rubber between the fitting surfaces of the intermediate sleeve and the outer cylinder member, the fluid tightness of the pressure receiving chamber is advantageously ensured.

  Further, in the fluid-filled cylindrical vibration isolator according to the present invention, the intermediate sleeve is formed with the second window portion at the formation portion of the through space, and the bag-shaped rubber elastic body is disposed in the through space. The bag-shaped rubber elastic body is opened to the outer peripheral surface through the second window portion by fixing the opening peripheral edge portion of the bag-shaped rubber elastic body to the opening edge portion of the second window portion of the intermediate sleeve. In addition, a structure in which the outer chamber member is fitted and fixed to the intermediate sleeve and the second window portion is covered to form the equilibrium chamber is preferably employed.

  According to such a structure, an equilibrium chamber enclosing an incompressible fluid is easily formed. Further, for example, by interposing a seal rubber between the fitting surfaces of the intermediate sleeve and the outer cylinder member, the fluid tightness of the equilibrium chamber is advantageously ensured. Preferably, the main rubber elastic body and the bag-like rubber elastic body are integrally formed, so that the manufacture becomes easier.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described. First, FIGS. 1 and 2 show an automobile engine mount 10 as an embodiment according to the fluid-filled cylindrical vibration isolator of the present invention. The engine mount 10 includes an inner tube member 12 as an inner shaft member and an outer tube member 14 as an outer tube member positioned at a predetermined distance in the radial direction and interposed therebetween. The main rubber elastic body 16 is elastically connected to each other. The engine mount 10 is fixed to an attachment member on the power unit side as one member to which the inner cylinder fitting 12 is vibration-proof connected (not shown), and the outer cylinder fitting 14 as the other member to be vibration-proof connected (not shown). By fixing to the mounting member on the body side, the power unit is supported to be vibration-proof with respect to the body.

  More specifically, the inner cylinder fitting 12 has a small-diameter cylindrical shape. Bolts, rods, and the like are inserted into the inner hole of the inner cylinder fitting 12 and are fixed to the mounting member on the power unit side. Further, a stopper member 18 is assembled to the inner cylinder fitting 12.

  The stopper member 18 has a substantially cylindrical shape, and is formed using a hard synthetic resin material, a metal material, or the like. The stopper member 18 is fixed to the outer peripheral surface of the inner cylindrical metal member 12 by insert molding. Accordingly, the stopper member 18 protrudes outward from the outer peripheral surface of the inner cylindrical metal member 12 in the radial direction (perpendicular to the axis). Since the axial length of the stopper member 18 is smaller than the axial length of the inner cylinder fitting 12, both axial ends of the inner cylinder fitting 12 protrude from both axial sides of the stopper member 18, respectively. . The stopper member 18 may be externally fixed to the inner cylinder fitting 12 after being molded separately from the inner cylinder fitting 12. A more detailed structure of the stopper member 18 will be described later as an explanation of the stopper mechanism.

  Further, a metal sleeve 20 having a large-diameter cylindrical shape is disposed on the outer side in the radial direction of the inner cylinder fitting 12, and is positioned around the inner cylinder fitting 12 including the stopper member 18 at a predetermined distance. I'm hurt. The inner cylinder fitting 12 and the metal sleeve 20 are positioned substantially concentrically with no support load applied to the mount 10. A first window portion 22 and a second window portion 24 that open in a rectangular shape in a direction perpendicular to the axis (radial direction) are penetrated and formed at a predetermined distance in the circumferential direction in the central portion of the metal sleeve 20 in the axial direction. Yes. Particularly in the present embodiment, with respect to the circumferential length, the first window portion 22 is approximately 1/3 to 1/2 of the metal sleeve 20 and the second window portion 24 is approximately 1/6 of the metal sleeve 20. The first window portion 22 extends more in the circumferential direction than the second window portion 24.

  A first connecting plate portion 26 and a second connecting plate portion 28 are provided between the first window portion 22 and the second window portion 24 in the metal sleeve 20 in the circumferential direction. These connecting plate portions 26 and 28 have a cross section that opens concavely outward in the radial direction, and extend in a predetermined length in the circumferential direction. In particular, the circumferential length of the first connecting plate portion 26 is the first. The circumferential length of the window portion 22 is substantially the same, and the circumferential length of the second connecting plate portion 28 is substantially the same as the circumferential length of the second window portion 24. That is, the first connecting plate portion 26 is larger in the circumferential direction than the second connecting plate portion 28.

  In other words, in the metal sleeve 20, a pair of ring portions 30, 30 having a large-diameter cylindrical shape arranged on the same axis at a predetermined distance from each other in the axial direction straddle between those axially opposed surfaces. The first connecting plate portion 26 and the second connecting plate portion 28 are integrally connected to each other, and the openings between the axially opposed surfaces of the ring portions 30 and 30 are the first and second connecting plate portions 26. , 28, the first window portion 22 and the second window portion are respectively provided between the pair of circumferential directions of the first and second connecting plate portions 26, 28 between the axially facing surfaces of the ring portions 30, 30. 24 is formed.

  A main rubber elastic body 16 is disposed between the inner cylinder 12 and the metal sleeve 20. The main rubber elastic body 16 has a thick, substantially cylindrical shape, and its outer peripheral surface is the inner peripheral surface of the metal sleeve 20, that is, the inner peripheral surface of the pair of ring portions 30 and 30, and the first and second connecting plates. The inner peripheral surfaces are vulcanized and bonded to the inner peripheral surfaces of the portions 26 and 28, and the inner peripheral surface is vulcanized and bonded to the outer peripheral surface of the inner tube 12 and the outer peripheral surface of the stopper member 18. As a result, the inner cylindrical metal member 12 and the metal sleeve 20 are elastically connected by the main rubber elastic body 16, and the main rubber elastic body 16 is connected to the inner cylindrical metal member 12 and the stopper member 18 as shown in FIGS. , Formed as an integrally vulcanized molded product 32 provided with a metal sleeve 20.

  A seal rubber integrally formed with the main rubber elastic body 16 is formed on substantially the entire outer peripheral surface of the metal sleeve 20, that is, on the outer peripheral surface of the pair of ring portions 30, 30 and the outer peripheral surfaces of the first and second connecting plate portions 26, 28. The layer 34 is applied over substantially the whole, and the outer diameter of the seal rubber layer 34 is substantially the same over the whole. In particular, on the outer peripheral surface of the seal rubber layer 34 attached to the ring portion 30, a plurality of strips of seal lips 36 extending continuously in the circumferential direction are projected.

  Further, a first pocket portion 38 is formed on one side of the main rubber elastic body 16 in the radial direction (in FIG. 1 and 2) sandwiching the inner cylindrical metal fitting 12. The first pocket portion 38 extends in the circumferential direction of the main rubber elastic body 16 by a predetermined length (approximately 1/3 to 1/2 in the present embodiment) and has a rectangular shape outward in the radial direction. An opening is formed, and this opening portion opens on the outer peripheral surface through the first window portion 22 of the metal sleeve 20. Further, the bottom portion (wall portions on both sides in the circumferential direction) of the first pocket portion 38 has a depth dimension reaching the vicinity of the outer peripheral surface of the inner cylindrical metal member 12 and extends substantially flat in a direction substantially orthogonal to the opening direction.

  Further, a slit 40 as a through space is formed on the other side (in FIG. 1 and FIG. 2B) in the main rubber elastic body 16 in the radial direction across the inner cylinder fitting 12. The slit 40 penetrates the main rubber elastic body 16 in the axial direction and extends in the circumferential direction by a predetermined length (substantially a half circumference in the present embodiment), and has a substantially arc shape when viewed in the axial direction.

  That is, in the integrally vulcanized molded product 32 of the main rubber elastic body 16, the first pocket portion 38 is provided in one radial direction across the inner cylinder fitting 12 and the slit 40 is provided in the other radial direction. Thus, a first elastic connecting portion 42 and a second elastic connecting portion 44 made of the main rubber elastic body 16 are provided between the first pocket portion 38 and the slit 40. In other words, the inner cylinder fitting 12 and the metal sleeve 20 are substantially elastically connected by the first elastic connecting portion 42 and the second elastic connecting portion 44. The pair of elastic connecting portions 42 and 44 has a plate shape whose thickness decreases from the stopper member 18 fixed to the inner cylinder fitting 12 toward the metal sleeve 20, and is substantially sandwiched between the inner cylinder fitting 12. It has a symmetrical shape.

Here, the axis perpendicular direction line extending in the vertical direction in FIG. 1 passing through the center of the inner cylinder fitting 12 is defined as a first axis perpendicular direction line: l ₁ and passing through the center of the inner cylinder fitting 12 in FIG. An axis perpendicular direction line extending in the left-right direction and orthogonal to the first axis perpendicular direction line: l ₁ is defined as a second axis perpendicular direction line: l ₂ .

The first elastic connecting portion 42 is disposed on one side in the radial direction (left in FIG. 1) sandwiching the inner cylinder fitting 12 between the inner cylinder fitting 12 and the metal sleeve 20, and is substantially the inner peripheral surface. The center is vulcanized and bonded to the outer peripheral surface of the stopper member 18 in a form positioned on the second axis perpendicular direction line: l ₂ , and the outer peripheral surface is the periphery of the first connecting plate portion 26 in the metal sleeve 20. It is vulcanized and bonded to the inner peripheral surface near the end of one direction (left in FIG. 1). Thereby, the 1st elastic connection part 42 is extended substantially parallel to the _2nd axis perpendicular direction line: l2.

The second elastic connecting portion 44 is arranged on the other side in the radial direction (right in FIG. 1) sandwiching the inner cylinder fitting 12 between the inner cylinder fitting 12 and the metal sleeve 20, and the center of the inner peripheral surface There second axis perpendicular line: Initial pocket portion 38 side in the circumferential direction is allowed positions deviate to embodiment respect l _2, together with the bonded by vulcanization to the outer peripheral surface of the stopper member 18, the outer periphery The surface is vulcanized and bonded to the inner peripheral surface in the vicinity of one end (left in FIG. 1) of the second connecting plate portion 28 in the metal sleeve 20 in the circumferential direction. As a result, the circumferential center line: l ₃ passing through the center of the inner cylindrical metal member 12 in the second elastic coupling portion 44 is in the circumferential direction on the first pocket portion 38 side with respect to the _second axis perpendicular direction line: l ₂ . Is inclined at a predetermined angle: θ1.

Accordingly, a direction in which the first elastic coupling portion 42 and the second elastic coupling portion 44 face each other through the center of the inner cylindrical metal member 12 is inclined in the circumferential direction with respect to the second axis perpendicular direction line: l ₂ . ing. Then, both the circumferential wall portions of the first pocket portion 38 are arranged in the width direction of the first elastic coupling portion 42 and the second elastic coupling portion 44 having substantially the same shape and size as each other (in FIG. ), The circumferential center line of the first pocket portion 38 passing through the center of the inner cylindrical fitting 12 is l ₄ , and the second elastic connecting portion 44 is perpendicular to the second axis. Like the circumferential direction inclined with respect to the direction line: l ₂ , the first axis perpendicular direction line: l ₁ is inclined at a predetermined angle: θ 2 in the circumferential direction. As a result, in the main rubber elastic body 16 including the first elastic connecting portion 42 and the second elastic connecting portion 44, one elastic main axis in the direction perpendicular to the axis is the circumferential center line of the first pocket portion 38. : It is positioned on the approximate line of l ₄ , and is inclined at a predetermined angle with respect to the first axis perpendicular direction line: l ₁ .

Inclination angle: θ1 of second elastic connecting portion 44 with respect to second axis perpendicular direction line: l _2, and circumferential center line of first pocket portion 38: l ₄ with respect to first axis perpendicular direction line: l ₁ The angle of inclination: θ2 is set according to the required damping characteristics in the direction of vibration input in the state of being mounted on the automobile described later, and is not particularly limited. For example, in the present embodiment, θ1 = 10 to 45 ° and θ2 = 10 to 45 °.

Further, both circumferential wall portions of the slit 40 that are opposed to the first pocket portion 38 in the radial direction across the inner cylindrical metal fitting 12 are in the width directions of the first elastic connecting portion 42 and the second elastic connecting portion 44. By including the other (upper in FIG. 1) wall portion, the circumferential center line of the slit 40 passing through the center of the inner cylindrical fitting 12 is the circumferential center line of the first pocket portion 38: l It is located on the same line as ₄ . As a result, the opposing direction of the first pocket portion 38 and the slit 40 in the direction perpendicular to the axis is relatively inclined with respect to the first axis perpendicular direction line: l ₁ .

  In addition, a diaphragm 46 as a flexible film is formed at the edge of the second window portion 24 of the metal sleeve 20 and is formed integrally with the main rubber elastic body 16 and is made of a thin bag-like rubber elastic body that can be easily deformed. It is fixed. The diaphragm 46 is disposed so as to bulge from the second window portion 24 toward the slit 40 forming portion side in the integrally vulcanized molded product 32 of the main rubber elastic body 16. A second pocket portion 48 that opens to the outer peripheral surface through the second window portion 24 of the metal sleeve 20 is provided on the opposite side of the slit 40 across the diaphragm 46.

In particular, in the present embodiment, the second pocket portion 48 is formed in the slit 40 (first pocket portion 38) with respect to the first axis-perpendicular direction line: l ₁ in the circumferential direction around the central axis of the inner cylinder fitting 12 in the slit 40. By being provided on the same side as the inclination direction of the circumferential center line (l ₄ ), the slit 40 is biased to be positioned on one side (right side in FIG. 1) in the circumferential direction. In short, the second pocket portion 48 is provided on the second elastic coupling portion 44 side that constitutes one circumferential wall portion of the slit 40.

  A concave groove 50 is formed at the center of the portion of the seal rubber layer 34 that is attached to the first connecting plate portion 26. The concave groove 50 continuously extends in the circumferential direction in a cross section that opens in a concave shape on the outer peripheral surface, one end in the circumferential direction is connected to the first pocket portion 38, and the other end in the circumferential direction is the first. Two pockets 48 are connected.

  The outer cylinder fitting 14 having a large-diameter cylindrical shape is extrapolated to such an integrally vulcanized molded product 32 of the main rubber elastic body 16, and the outer cylinder fitting 14 is subjected to diameter reduction processing such as eight-way drawing. ing. As a result, the outer cylinder fitting 14 is fitted and fixed to the metal sleeve 20 via the seal rubber layer 34, and is positioned substantially concentrically outside the inner cylinder fitting 12 in the radial direction. Particularly, based on the fact that the seal lip 36 of the seal rubber layer 34 is interposed between the outer cylinder fitting 14 and each ring portion 30 of the metal sleeve 20 by being compressed and deformed, the outer cylinder fitting 14 has a pair of ring portions 30, 30, and the opening portion of the first pocket portion 38 and the opening portion of the second pocket portion 48 are covered with the outer tube metal fitting 14 in a fluid-tight manner.

A part of the wall portion is formed of the main rubber elastic body 16 in the sealed interior formed by the first pocket portion 38 and the outer cylindrical metal member 14, and pressure fluctuation occurs due to elastic deformation of the main rubber elastic body 16. A pressure receiving chamber 52 is formed. In the sealed interior formed by the second pocket portion 48 and the outer cylindrical metal member 14, there is an equilibrium chamber 54 in which a part of the wall portion is formed by the diaphragm 46 and volume change is easily allowed by elastic deformation of the diaphragm 46. Is formed. Each of the pressure receiving chamber 52 and the equilibrium chamber 54 is filled with an incompressible fluid. In short, a pressure receiving chamber 52 filled with an incompressible fluid is formed inside the main rubber elastic body 16, and an equilibrium chamber 54 filled with an incompressible fluid is formed in the slit 40. As such an incompressible fluid, water, alkylene glycol, polyalkylene glycol, silicone oil or the like is adopted. However, in order to advantageously obtain a vibration isolation effect based on a fluid action such as a resonance action of the fluid described later, the viscosity is A low viscosity fluid of 0.1 Pa · s or less is suitably employed. Note that the incompressible fluid is sealed in the pressure receiving chamber 52 and the equilibrium chamber 54 by, for example, assembling the outer tube fitting 14 to the integrally vulcanized molded product 32 of the main rubber elastic body 16 in the incompressible fluid. Is advantageously realized. Further, as is clear from the above description, the circumferential center line of the pressure receiving chamber 52 passing through the center of the inner cylindrical metal member 12 is the same as the circumferential center line: l _{4 of} the first pocket portion 38. Thus, the first axis perpendicular direction line: l ₁ is inclined at a predetermined angle: θ 2 in the circumferential direction. Further, the equilibrium chamber 54 is the same as the inclination direction of the circumferential center line: l ₄ of the pressure receiving chamber 52 with respect to the first axis-perpendicular direction line: l ₁ in the circumferential direction around the central axis of the inner tube 12 in the slit 40. It is also clear that it is formed on the side.

  Further, based on the fact that the opening of the concave groove 50 formed on the outer peripheral surface of the metal sleeve 20 is covered fluid-tightly by the outer cylinder fitting 14 with the seal rubber layer 34 interposed therebetween, the metal sleeve 20 and the outer cylinder fitting 14 are covered. An orifice passage 56 extending in a tunnel shape with a predetermined length in the circumferential direction is formed therebetween. One end of the orifice passage 56 is connected to the pressure receiving chamber 52, and the other end of the orifice passage 56 is connected to the equilibrium chamber 54. Accordingly, the pressure receiving chamber 52 and the equilibrium chamber 54 are communicated with each other through the orifice passage 56, and the flow of fluid through the orifice passage 56 is based on relative pressure fluctuations in the two chambers 52 and 54 at the time of vibration input. The amount is secured, and the anti-vibration effect is exhibited based on the fluid action such as the resonance action of the fluid.

  In the present embodiment, the resonance frequency of the fluid that flows through the orifice passage 56 based on the relative pressure fluctuation generated between the pressure receiving chamber 52 and the equilibrium chamber 54 at the time of vibration input is, for example, a large low frequency of about 10 Hz. Tuning so that anti-vibration effects (high damping characteristics) based on the resonance action of the fluid etc. are advantageously exhibited against vibrations that should be anti-vibration such as engine shake of amplitude and idling vibration of high frequency and small amplitude of about 15 to 30 Hz. Has been. The tuning of the orifice passage 56 takes into account the rigidity of the wall springs of the pressure receiving chamber 52 and the equilibrium chamber 54 (characteristic value corresponding to the amount of pressure change necessary for changing the unit volume) and the like. This is possible by adjusting the passage length and the passage cross-sectional area. Generally, the frequency at which the phase of the pressure fluctuation transmitted through the orifice passage 56 changes to bring it into a substantially resonant state is defined as the tuning frequency of the orifice passage 56. Can be grasped as.

  The stopper member 18 is integrally provided with a bound stopper 58 as a first stopper and a rebound stopper 60 as a second stopper. The bound stopper 58 and the rebound stopper 60 have a block shape extending in parallel with the inner cylinder fitting 12 with a substantially constant rectangular cross section, and the stopper member 18 in which the bound stopper 58 is fixed to the inner cylinder fitting 12 in the pressure receiving chamber 52. The rebound stopper 60 protrudes from the stopper member 18 fixed to the inner cylinder fitting 12 in the slit 40 toward the outer cylinder fitting 14 at a prescribed height. It protrudes.

  The protruding front end surfaces of the bound stopper 58 and the rebound stopper 60 are opposed to the inner peripheral surface of the outer cylindrical metal member 14 with a predetermined distance in the direction perpendicular to the axis, and the opposed front end surfaces of the outer cylindrical metal member 14 are opposed to each other. The curved surface corresponds to the shape of the inner peripheral surface of the part. In addition, a thin buffer rubber layer 62 integrally formed with the main rubber elastic body 16 is attached to the outer peripheral surface including the protruding front end surfaces of the bound stopper 58 and the rebound stopper 60 over substantially the entire surface.

  In particular, in the present embodiment, both end portions in the axial direction of the rebound stopper 60 protrude radially outward from the central portion in the axial direction. In other words, the diameter dimension of the central portion in the axial direction of the rebound stopper 60 is By making it smaller than the radial dimension, the axial cross section has a concave shape that opens radially outward. By filling a rubber elastic body integrally formed with the main rubber elastic body 16 in the concave portion, the thickness dimension (rubber volume) of the shock absorbing rubber layer 62 attached to the small-diameter axial center portion is reduced. The thickness is substantially larger than the thickness of the buffer rubber layer 62 attached to both ends of the large-diameter axial direction. The central portion in the axial direction of the rebound stopper 60 is positioned opposite to the first connecting plate portion 26 of the metal sleeve 20 through the thick buffer rubber layer 62, and each axial portion of the rebound stopper 60 is also in the axial direction. The end portion is opposed to each ring portion 30 of the metal sleeve 20 with a thin buffer rubber layer 62 interposed therebetween.

In the pressure receiving chamber 52, the protruding direction line: l ₅ passing through the center of the bound stopper 58 protruding from the inner cylinder fitting 12 toward the outer cylinder fitting 14 is changed from the first axis perpendicular direction line: l ₁ to the first. The pressure receiving chamber 52 located on the side of the elastic coupling portion 42 is positioned away from the first axially perpendicular direction line: l ₁ by a predetermined distance toward the circumferential center line: l ₄ . The bound stopper 58 protrudes from the first axis perpendicular direction line: l ₁ so as to be deviated in the inclined direction of the circumferential center line: l ₄ of the pressure receiving chamber 52.

  Along with this, the base end portion of the bound stopper 58 protruding from the inner cylindrical metal member 12 is substantially symmetrical in the opposing direction of the first elastic connecting portion 42 and the second elastic connecting portion 44 that are substantially symmetrical in the main rubber elastic body 16. It is positioned at the center and positioned on the elastic main axis in the direction perpendicular to the axis of the main rubber elastic body 16.

Further, the protrusion direction line passing through the center of the bound stopper 58: l ₅ extends in parallel with the first axis perpendicular direction line: l ₁ , so that the bound stopper 58 is converted into the first axis perpendicular direction line: l _1. It extends in parallel to.

On the other hand, a projecting direction line passing through the center of the rebound stopper 60 projecting from the inner cylinder fitting 12 toward the outer cylinder fitting 14 in the slit 40 is positioned on the first axis perpendicular direction line: l ₁ . Thus, the rebound stopper 60, a first direction perpendicular to the axis line: with are projected onto the l _1, a first direction perpendicular to the axis line: extends parallel to the bound stopper 58 which extends parallel to the l ₁ ing.

In particular, in the present embodiment, in the circumferential direction around the central axis of the inner cylindrical metal member 12 in the slit 40, the same side as the inclination direction of the circumferential center line: l ₄ of the pressure receiving chamber 52 with respect to the first axis perpendicular direction line: l ₁ . Thus, the equilibrium chamber 54 is formed on one side (right side in FIG. 1) of the rebound stopper 60 in the circumferential direction.

  In the automotive engine mount 10 having the above-described structure, the inner cylinder fitting 12 is fixed to the mounting member on the power unit via a bolt or a rod inserted through the inner hole, and the outer cylinder fitting 14 is provided with the outer cylinder fitting 14. When the mounting bracket is fixed to the vehicle body by being press-fitted into a mounting bracket having a circular hole (not shown), the power unit is interposed between the power unit and the body to support the body against vibration. ing.

The main load exerted on the engine mount 10 is a bounce / rebound load that is input in a substantially vertical direction when overcoming a step in an automobile. In mounting on an automobile, the first axis perpendicular direction line: l ₁ in the mount 10 is the main load input direction line, so the first axis perpendicular direction line: l ₁ is substantially vertical. And the second axis-perpendicular line: l ₂ extends in a substantially horizontal direction. Therefore, the bound stopper 58 and the rebound stopper 60 extend in parallel to the input direction of the main load in the bound / rebound direction exerted in the direction perpendicular to the axis with respect to the inner cylinder fitting 12 and the outer cylinder fitting 14, and the inner cylinder fitting. A circumferential center line: l _{4 of the} pressure receiving chamber 52 passing through the center of 12 is mounted so as to be inclined by a predetermined angle: θ2 in the circumferential direction. Further, the first elastic connecting portion 42 of the main rubber elastic body 16 extends substantially parallel to the horizontal direction based on the fact that the second axis-perpendicular line: l ₂ extends in the substantially horizontal direction, and the main rubber The second elastic coupling portion 44 of the elastic body 16 is attached to be inclined at a predetermined angle: θ1 in the circumferential direction.

  Under such a mounted state, when an excessive load in the bound direction is input between the inner cylinder fitting 12 and the outer cylinder fitting 14, the inner cylinder fitting 12 and the outer cylinder fitting 14 are displaced relative to each other, and the cushion rubber. The layers 62 are in contact with each other via a bound stopper 58 to which the layer 62 is attached. As a result, the relative displacement amount in the bounce direction in the inner and outer cylinder fittings 12 and 14 is buffered and reliably limited by the bounce stopper mechanism including the bounce stopper 58 and the buffer rubber layer 62.

  Further, when an excessive load in the rebound direction is input between the inner cylinder fitting 12 and the outer cylinder fitting 14, the inner cylinder fitting 12 and the outer cylinder fitting 14 are relatively displaced, and the buffer rubber layer 62 is attached. The rebound stopper 60 and the metal sleeve 20 are in contact with each other. As a result, the relative displacement amount in the rebound direction of the inner and outer tube fittings 12 and 14 is buffered and reliably limited by the rebound stopper mechanism including the rebound stopper 60, the buffer rubber layer 62, and the metal sleeve 20.

  Furthermore, in this embodiment, since the opposing direction in the direction perpendicular to the axis of the first elastic connecting portion 42 and the second elastic connecting portion 44 is inclined with respect to the horizontal direction, in particular, the bound / rebound load ( Based on the elastic deformation of the main rubber elastic body 16 including the first and second elastic coupling portions 42 and 44, when a vibration in question is input in a direction inclined to the input direction of the main load), Excellent damping performance can be obtained.

  Here, since the stopper member 18 in which the bound stopper 58 and the rebound stopper 60 are integrally formed is insert-molded in the inner tube metal fitting 12 and provided in the integral vulcanization molded product 32 of the main rubber elastic body 16, The score can be advantageously reduced and the production efficiency can be effectively improved.

Further, in particular, the bounce stopper 58 is provided so as to be biased in the inclination direction of the circumferential center line (l ₄ ) of the pressure receiving chamber 52 with respect to the input direction line (l ₁ ) of the bounce load passing through the center of the inner cylinder fitting 12. Therefore, the free lengths of the first elastic connecting portion 42 and the second elastic connecting portion 44 constituting the wall portions on both sides in the circumferential direction of the pressure receiving chamber 52 sandwiching the protruding base end portion of the bound stopper 58 are substantially the same. It is the same. As a result, it is reduced or avoided that excessive stress is locally generated in the main rubber elastic body 16 including the first and second elastic coupling portions 42 and 44 when the bound load is input. Thus, the durability performance of the main rubber elastic body 16 and the engine mount 10 can be sufficiently secured.

  Further, the base end portion of the bound stopper 58 is positioned substantially on the circumferential center line of the pressure receiving chamber 52, and the protruding direction of the bound stopper 58 extends parallel to the input direction line of the main load. Thus, the volumes on both sides in the circumferential direction across the bound stopper 58 in the pressure receiving chamber 52 are substantially the same. Therefore, since the malfunction of the fluid flow action due to the provision of the constricted portion in the pressure receiving chamber 52 is eliminated, the vibration isolation performance based on the fluid flow action can be stably obtained.

Furthermore, in the present embodiment, the circumferential center of the pressure receiving chamber 52 with respect to the input direction line (l ₁ ) of the main load passing through the center of the inner cylinder fitting 12 in the circumferential direction around the central axis of the inner cylinder fitting 12 in the slit 40. Since the equilibrium chamber 54 is formed on the same side as the inclination direction of the line (l ₄ ), the equilibrium chamber 54 is positioned on one side in the circumferential direction of the rebound stopper 60. That is, since the circumferential center line (l ₄ ) of the slit 40 opposed to the pressure receiving chamber 52 in the direction perpendicular to the axis is inclined with respect to the input direction line of the main load, the rebound stopper 60 extending in the input direction line. However, in the slit 40, the slit 40 extends while being inclined toward the circumferential center line of the slit 40. As a result, using the large space formed on the opposite side of the slit 40 in the protruding direction of the rebound stopper 60, the equilibrium chamber 54 is configured with a large volume, and in addition, the equilibrium chamber 54 is connected to the rebound stopper 60. Interference is avoided and stable stopper performance is obtained.

  The embodiment of the present invention has been described in detail above, but this is merely an example, and the present invention is not limited to a specific description in the embodiment, and is based on the knowledge of those skilled in the art. The present invention can be implemented with various changes, modifications, improvements, and the like. Further, it goes without saying that such embodiments are all included in the scope of the present invention without departing from the gist of the present invention.

  For example, the shape, size, structure, and the like of the bound stopper 58 and the rebound stopper 60 according to the embodiment are changed according to the required stopper performance, and are not limited to those illustrated.

  Moreover, in the said embodiment, although the buffer rubber layer 62 adhere | attached on the protrusion front end surface of the bound stopper 58 or the rebound stopper 60 was integrally formed with the main body rubber elastic body 16, of course, it should be formed separately. Is also possible.

  Furthermore, in the said embodiment, although the input direction of the main load was made into the perpendicular direction into which a bound / rebound load is inputted in the mounting state to a motor vehicle, even if it is the direction which inclines with respect to a perpendicular direction good.

  Furthermore, in the above-mentioned embodiment, the orifice channel 56 is formed by covering the concave groove 50 formed on the outer peripheral surface of the metal sleeve 20 with the outer cylinder fitting 14, but for example, JP-A-2-26337 is disclosed. As shown in Japanese Laid-Open Patent Publication No. 2001, etc., an orifice passage may be formed by providing a groove or the like in an orifice member having a separate structure from an integrally vulcanized molded product of a main rubber elastic body.

  In addition, in the said embodiment, although the specific example of what applied this invention to the engine mount for motor vehicles was shown, this invention is other than the body mount, suspension bush, etc. for motor vehicles, or various things used other than a motor vehicle. Of course, the present invention can also be applied to other vibration isolators.

FIG. 3 is a cross-sectional view showing an automobile engine mount as one embodiment of the present invention, corresponding to the II cross section of FIG. 2. The longitudinal cross-sectional view of the engine mount for the vehicles. FIG. 3 is a side view of an integrally vulcanized molded product of a main rubber elastic body that constitutes a part of the engine mount for the automobile. The side view different from FIG. 3 of the integral vulcanization molded product of the main body rubber elastic body. The bottom view of the integral vulcanization molding product of the main body rubber elastic body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Engine mount for motor vehicles, 12: Inner cylinder metal fitting, 14: Outer cylinder metal fitting, 16: Rubber elastic body of main body, 40: Slit, 46: Diaphragm, 52: Pressure receiving chamber, 54: Equilibrium chamber 56: Orifice passage, 58: Bound stopper, 60: Rebound stopper

Claims (4)

An outer cylinder member is disposed on the outer peripheral side of the inner shaft member, and the inner shaft member and the outer cylinder member are connected by a main rubber elastic body on one side in a direction perpendicular to the axis across the inner shaft member. In addition, on the other side in the direction perpendicular to the axis across the inner shaft member, there is formed a through space that penetrates between the inner shaft member and the outer cylindrical member in the axial direction, while the main rubber elastic body A pressure receiving chamber is formed inside the chamber, and an equilibrium chamber having a wall portion formed of a flexible membrane is formed in the through space. An incompressible fluid is enclosed in the pressure receiving chamber and the equilibrium chamber. And a fluid-filled cylindrical vibration isolator that is communicated with each other through an orifice passage.
The circumferential center line of the pressure receiving chamber passing through the center of the inner shaft member is inclined in the circumferential direction with respect to the input direction of the main load exerted on the inner shaft member and the outer cylinder member in the direction perpendicular to the axis. A first stopper that protrudes from the inner shaft member toward the outer cylinder member in the pressure receiving chamber under the mounted state is an input of a main load that passes through the center of the inner shaft member. While projecting parallel to the input direction line of the main load passing through the center of the inner shaft member and deviating in the inclination direction of the circumferential center line of the pressure receiving chamber with respect to the direction line, A fluid-filled cylinder characterized in that a second stopper projecting from the inner shaft member toward the outer tube member is provided on the input direction line of the main load passing through the center of the inner shaft member. Mold vibration isolator.   In the circumferential space around the central axis of the inner shaft member, the through space is on the same side as the inclination direction of the circumferential center line of the pressure receiving chamber with respect to the input direction line of the main load passing through the center of the inner shaft member. The fluid-filled cylindrical vibration damping device according to claim 1, wherein the equilibrium chamber is formed on the one side in the circumferential direction of the second stopper by being positioned.   An intermediate sleeve is disposed on the outer peripheral side of the inner shaft member, and the intermediate sleeve is fixed to the outer peripheral surface of the main rubber elastic body. A first pocket portion is formed on the main rubber elastic body. A first window portion is formed in the intermediate sleeve, the first pocket portion is opened to the outer peripheral surface through the first window portion, and the outer cylindrical member is fitted and fixed to the intermediate sleeve. The fluid-filled cylindrical vibration isolator according to claim 1 or 2, wherein the pressure receiving chamber is formed by covering the first window portion. In the intermediate sleeve, a second window is formed at a portion where the through space is formed, and a bag-like rubber elastic body is disposed in the through space, and an opening of the bag-like rubber elastic body is provided. The peripheral edge portion is fixed to the opening edge of the second window portion of the intermediate sleeve, so that the bag-like rubber elastic body opens to the outer peripheral surface through the second window portion, and the outer sleeve is attached to the intermediate sleeve. The fluid-filled cylindrical vibration isolator according to claim 3, wherein the equilibrium chamber is formed by externally fixing a cylindrical member and covering the second window portion.

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