JP2008138819A - Cylindrical vibration damper and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylindrical vibration damper of novel structure in which a separate shaft end stopper member limiting the displacement of an inner shaft member relative to an outer tube member is assembled in a predetermined assembling direction by a simple assembly operation while avoiding the peeling of paint and dents at the assembling points and a novel method of manufacturing the cylindrical vibration damper. <P>SOLUTION: The inner shaft member 12 and the first outer tube member 20 to each other through a body rubber elastic body 16 to form a vibration damper body 24. A shaft end stopper member 34 is disposed on the axial both sides of the vibration damper body 24. The second outer tube member 22 is inserted onto the vibration damper body 24 and the shaft end stopper member 34, and the second outer tube member 22 is so processed as to be radially reduced. Consequently, the outer tube member 14 is formed by fitting the first outer tube member 20 and the second outer tube member 22 to each other, and the shaft end stopper member 34 is assembled to the outer tube member 14. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cylindrical vibration isolator suitably used as, for example, a suspension bush of an automobile, and a manufacturing method thereof.

  2. Description of the Related Art Conventionally, a cylindrical vibration isolator used as a suspension mount for an automobile is known. For example, as described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2000-88026), a cylindrical vibration isolator includes an inner cylindrical member and an outer cylindrical member that is arranged separately on the outer peripheral side of the inner axial member. The structure is elastically connected by an elastic body. The inner shaft member is fixed to one member to be vibration-proof connected, such as a vehicle body, and the outer cylinder member is fixed to the other member to be vibration-proof connected, for example, a suspension arm. The members to be vibration-proof connected are elastically connected to each other.

  By the way, in such a cylindrical vibration isolator, there may be provided a stopper mechanism that restricts the relative displacement between the inner shaft member and the outer cylinder member when a large load is input. In particular, the present inventor can effectively limit the relative displacement between the inner shaft member and the outer cylindrical member in the direction perpendicular to the axis or in the direction of twisting by providing shaft end stopper members at both axial ends of the inner shaft member. A stopper mechanism was devised. Specifically, such a stopper mechanism is, for example, a separate fixed shaft end provided with a cylindrical fixed tube member and a shaft end stopper rubber fixed to the fixed tube member and projecting toward the outer tube member side. The stopper member is fitted and fixed to both axial ends of the inner shaft member, and when the inner shaft member and the outer cylinder member are relatively displaced, the inner shaft member and the outer cylinder member are cushioned via the shaft end stopper rubber. This is realized by abutting against. By providing such a stopper mechanism, it is possible to advantageously realize improvement in durability, improvement in steering stability, and the like.

  However, as a result of further studies by the present inventors, in the cylindrical vibration isolator provided with such a shaft end stopper member, the shaft end stopper member is press-fitted and fixed to the inner shaft member. It has become clear that there is a risk that creases (galling creases) may occur during assembly, making press-fitting difficult, and the paint peeling off and causing rust and corrosion.

  Further, from the standpoint of advantageously limiting the relative displacement between the inner shaft member and the outer cylinder member, a pair of shaft end stopper members aligned in the circumferential direction may be provided at both axial ends of the inner shaft member. It is valid. However, while maintaining the state in which the shaft end stopper rubbers of the pair of shaft end stopper members are aligned with each other in the circumferential direction, the pair of shaft end stopper members are simultaneously press-fitted and fixed to both ends of the inner shaft member. Was extremely difficult. Further, when each shaft end stopper member is fitted to the inner shaft member one by one, there is a concern that a decrease in manufacturing efficiency due to an increase in the process may be a problem.

JP 2000-88026 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is a separate shaft end stopper member that limits the relative displacement between the inner shaft member and the outer cylinder member. With a new structure that can be assembled and positioned with high precision at a predetermined assembly position and direction, with simple assembly work, while avoiding paint peeling and wrinkles at the assembly location. The object is to provide a novel vibration damping device and a novel manufacturing method of the cylindrical vibration damping device, respectively.

  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 present invention related to a cylindrical vibration isolator is a cylindrical vibration isolator in which an inner shaft member and an outer cylindrical member spaced apart on the outer peripheral side thereof are connected by a main rubber elastic body, the inner shaft member and the outer peripheral side thereof The first outer cylinder member that is spaced apart from each other is connected by the main rubber elastic body to form a cylindrical vibration isolator main body, and protrudes toward the inner peripheral side from the fixed cylinder member and the fixed cylinder member A shaft end stopper member including a shaft end stopper rubber is disposed on both sides in the axial direction of the vibration isolator main body, and the vibration isolator main body and the shaft end stopper member are connected to the second outer cylinder member. The first outer cylinder member and the second outer cylinder member are fitted and fixed to each other by disposing the second outer cylinder member on the inner peripheral side of the second outer cylinder member. And the shaft end stopper member is connected to the outer cylinder member. Assembled, characterized in that the inner shaft member and the outer tubular member via the shaft end stopper rubber has to be brought into contact with the axial straight load input direction.

  In the cylindrical vibration isolator having the structure according to the present invention, the shaft end stopper member is assembled to the outer cylinder member side, and the second outer cylinder member is reduced in diameter by the second diameter reduction process. The outer cylinder member is pressed against the vibration isolator body and the shaft end stopper member from the outside in the radial direction so that the vibration isolator body and the shaft end stopper member are fitted and fixed to the second outer cylinder member. It has become. Therefore, it is possible to prevent the shaft end stopper member from being difficult to be assembled due to a dimensional error of the fixed cylinder member or the second outer cylinder member, and to easily assemble the shaft end stopper member to the vibration isolator body. I can do it.

  Moreover, since the shaft end stopper member is fixed to the vibration isolator main body by drawing the second outer cylinder member, between the pair of shaft end stopper members or between the shaft end stopper member and the vibration isolator main body. Even when a specific relative position, such as a direction in the circumferential direction, is set, relative alignment can be easily realized. That is, before the second outer cylinder member is subjected to diameter reduction processing, the shaft end stopper member and the vibration isolator main body are aligned in advance, and the shaft end stopper member and the vibration isolator main body in the aligned state are aligned. On the other hand, by fitting the second outer cylinder member by drawing, it is possible to easily realize the alignment of the shaft end stopper member and the vibration isolator main body.

  Further, in the cylindrical vibration isolator according to the present invention, the second outer cylinder member is subjected to a diameter reduction process so that the second outer cylinder member is radially outside the vibration isolator body and the shaft end stopper member. It is pressed from the side and fixedly assembled. Therefore, wrinkles and peeling of paint on the overlapping surface of the first outer cylinder member and the second outer cylinder member and the overlapping surface of the second outer cylinder member and the fixed cylinder member are unlikely to be a problem.

  In the cylindrical vibration isolator according to the present invention, the shaft end stopper rubber protrudes from the shaft end stopper rubber by forming recesses extending in the axial direction at the inner peripheral protruding top portions on both sides of the shaft direct load input direction. It is also possible to adopt a structure in which the height is changed in the circumferential direction.

  By adopting such a structure, it is possible to reduce the contact area at the initial contact of the shaft end stopper rubber and realize a buffering stopper effect.

  Further, in the cylindrical vibration isolator according to the present invention, a buffer rubber layer is formed on the portion of the inner shaft member where the shaft end stopper rubber is brought into contact with the shaft end stopper rubber and the buffer rubber. At least one of the contact surfaces of the layers is inclined with respect to the central axis of the inner shaft member, and the shaft end stopper rubber and the buffer are supported by relative displacement in the twisting direction of the inner shaft member and the outer cylinder member. A structure may be employed in which the contact surfaces of the shaft end stopper rubber and the buffer rubber layer are parallel to each other when the rubber layer is brought into contact therewith.

  According to this, when a load is input in a direction perpendicular to the axis, the contact area between the shaft end stopper rubber and the buffer rubber layer is reduced, and a buffering stopper effect can be realized. On the other hand, when a load is input in the twisting direction, the contact area between the shaft end stopper rubber and the buffer rubber layer is increased, and a more effective displacement limiting effect can be obtained.

  When the shaft end stopper rubber and the buffer rubber layer are brought into contact with each other due to the relative displacement of the inner shaft member and the outer cylinder member in the twisting direction, the shaft end stopper rubber and the buffer rubber layer extend over the entire contact surface. Need not be parallel to each other, and at least some of them may be parallel to each other.

  In the cylindrical vibration isolator having a structure according to the present invention, a large number of small protrusions may be integrally formed on the contact surface of the shaft end stopper rubber.

  According to such a structure, it is possible to advantageously prevent the generation of abnormal noise when the shaft end stopper rubber comes into contact. Further, the abutting area can be reduced, and the buffering abutting of the shaft end stopper rubber can be realized more advantageously.

  Moreover, the cylindrical vibration isolator according to the present invention can also be employed as a strut arm bush that is attached to a portion where the suspension arm is attached to the vehicle body.

  By adopting the cylindrical vibration isolator having the structure according to the present invention as the strut arm bush, the relative displacement in the twisting direction of the inner shaft member and the outer cylinder member is effectively limited, and the excessive turning angle of the wheel with respect to the steering operation Can be advantageously prevented. Therefore, it is possible to improve the steering stability of the vehicle.

  Further, in the cylindrical vibration isolator according to the present invention, the overlapping portion of the second outer cylinder member with the first outer cylinder member in the axially intermediate portion is press-fitted into the vibration isolation target member, It is also possible to adopt a structure in which both end portions in the axial direction of the second outer cylinder member are arranged apart from the vibration-proof target member.

  In the cylindrical vibration isolator having such a structure, a portion of the outer cylinder member that is press-fitted into the vibration isolation target member has a relatively high strength in which the first outer cylinder member and the second outer cylinder member are overlapped. By setting it as the portion, it is possible to advantageously prevent the outer cylinder member from being deformed when press-fitting and assembling to the vibration-proof target member.

  Note that the axially opposite end portions of the second outer cylinder member are spaced apart from the vibration isolation target member means that the second outer cylinder is mounted in the vibration isolation target member of the cylindrical vibration isolation device. A mode in which both end portions in the axial direction of the member are arranged so as to protrude in the axial direction from the vibration-proof target member, or a mode in which a predetermined distance is provided in the direction perpendicular to the axis with respect to the vibration-proof target member Say etc.

  In the cylindrical vibration isolator having the structure according to the present invention, both axial end portions of the second outer cylindrical member have a smaller diameter than the axial intermediate portion, and the shaft of the second outer cylindrical member Both end portions in the direction may be spaced apart from the vibration isolation target member, and the axially intermediate portion of the second outer cylinder member may be press-fitted into the vibration isolation target member.

  According to this, when the both ends in the axial direction of the second outer cylindrical member are made smaller in diameter than the press-fitting hole of the vibration isolation target member, when press-fitting assembly to the vibration isolation target member of the cylindrical vibration isolation device, It is possible to advantageously avoid peeling of paint or wrinkles at both axial end portions of the second outer cylinder member.

  In addition, the present invention relating to a method of manufacturing a cylindrical vibration isolator is provided with a first outer cylinder member spaced apart on the outer peripheral side of the inner shaft member, and the inner shaft member and the first outer cylinder member are connected to the main rubber. A step of preparing a cylindrical vibration isolator body connected by an elastic body, and a step of pre-compressing the main rubber elastic body by reducing the diameter of the first outer cylinder member in the vibration isolator body And a stopper rubber member fixed to a portion facing in one radial direction on the inner peripheral surface of the cylindrical fixed cylindrical member, and a shaft end stopper member projecting the stopper rubber toward the inner peripheral side in one radial direction. Preparing the shaft end stopper members on both sides in the axial direction of the vibration isolator main body, and extrapolating a second outer cylinder member to the vibration isolator main body and the shaft end stopper member, By reducing the diameter of the second outer cylinder member Characterized in that it comprises a step of assembling the vibration damping device body and the shaft end stopper member to said second outer tubular member.

  According to the manufacturing method of the cylindrical vibration isolator according to the present invention, by performing the diameter reduction processing for reducing the tensile stress of the main rubber elastic body before the second outer cylindrical member is assembled, The force required for drawing can be kept small. In addition, in order to perform effective pre-compression on the main rubber elastic body, a relatively large amount of deformation (reduction ratio) is required. Here, since the main rubber elastic body is pre-compressed before the first outer cylinder member and the second outer cylinder member are overlaid, a large amount of deformation can be advantageously realized with a small squeezing force. . Therefore, effective pre-compression can be easily exerted on the main rubber elastic body.

  The second outer cylinder member is pressed against the first outer cylinder member of the vibration isolator main body and the fixed cylinder member of the shaft end stopper member from the outside in the direction perpendicular to the axis, so that the vibration isolator main body and the shaft are It can be assembled to the end stopper member. Thereby, the vibration isolator main body, the pair of shaft end stopper members, and the second outer cylinder member can be assembled at the same time by a single diameter reduction process, and the number of processes can be reduced. In addition, when the vibration isolator body and the shaft end stopper member need to be aligned at specific relative positions, these members are aligned in advance before the diameter reduction processing of the second outer cylinder member. Therefore, it can be easily assembled in a state aligned with a predetermined position. Furthermore, it is possible to realize highly accurate alignment as compared with assembly by press-fitting.

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

  That is, FIGS. 1 and 2 show a strut arm bush 10 for an automobile which is an embodiment of a cylindrical vibration isolator having a structure according to the present invention. The strut arm bush 10 has a structure in which an inner cylinder fitting 12 as an inner shaft member and an outer cylinder fitting 14 as an outer cylinder member are elastically connected by a main rubber elastic body 16. The bush 10 has an inner cylinder fitting 12 attached to a vehicle body (not shown), and an outer cylinder fitting 14 is attached to a strut arm 18 as a vibration isolation target member, whereby the strut arm 18 is attached to the vehicle body side. The strut arm 18 is connected to the vehicle body in a vibration-proof manner. In the following description, the axial direction of the bush 10 refers to the left-right direction in FIG. The main axial direct load input direction when the bush 10 is mounted on the vehicle is the vertical direction in FIGS. 1 and 2 show the bush 10 in a non-mounted state on the vehicle.

  More specifically, the inner cylinder fitting 12 has a thick, small-diameter, generally cylindrical shape, and is formed of a metal material such as an aluminum alloy, for example. Moreover, the inner cylinder metal fitting 12 which concerns on this embodiment is extended with the fixed cross-sectional shape over the substantially full length of the axial direction. In addition, although the formation material of the inner cylinder metal fitting 12 is not specifically limited, It is desirable to form with the material of the material which does not rust easily.

  The outer cylinder fitting 14 includes a first outer cylinder fitting 20 as a first outer cylinder member and a second outer cylinder fitting 22 as a second outer cylinder member. The first outer cylinder fitting 20 has a substantially cylindrical shape that is thinner and larger in diameter than the inner cylinder fitting 12, and is formed of, for example, a metal material that does not easily rust, such as an aluminum alloy. Further, the first outer cylinder fitting 20 is disposed on the outer peripheral side so as to surround the inner cylinder fitting 12. The first outer cylinder fitting 20 has a sufficiently small axial dimension as compared with the inner cylinder fitting 12.

  Further, the inner cylinder fitting 12 and the first outer cylinder fitting 20 are connected to each other by a main rubber elastic body 16. The main rubber elastic body 16 has a thick, substantially cylindrical shape, and an inner peripheral surface thereof is vulcanized and bonded to the inner cylinder fitting 12, and an outer peripheral surface is vulcanized and bonded to the first outer cylinder fitting 20. ing.

  In such a main rubber elastic body 16, the inner cylinder fitting 12 and the first outer cylinder fitting 20 are set in a main rubber molding die (not shown), and the rubber material of the main rubber elastic body 16 is applied to the main rubber molding die. By filling, as shown in FIGS. 3 and 4, it is formed as an integrally vulcanized molded product 24 as a vibration isolator body provided with the inner cylinder fitting 12 and the first outer cylinder fitting 20. In the integrally vulcanized molded product 24 of the main rubber elastic body 16, the inner cylinder fitting 12 and the first outer cylinder fitting 20 are not attached to the vehicle, as shown in FIGS. It is arranged eccentrically in one radial direction.

  Further, in the integrally vulcanized molded product 24 of the main rubber elastic body 16, the first outer cylinder fitting 20 is subjected to a first diameter reduction process such as an eight-way drawing. Then, the integrally vulcanized molded product 24 of the main rubber elastic body 16 has an outer diameter dimension as shown in FIGS. 5 and 6 as compared with the state at the time of vulcanization molding shown in FIGS. Is reduced. Thereby, the tensile stress of the main rubber elastic body 16 can be reduced or avoided, and the durability can be improved. In the present embodiment, as shown in FIG. 5, the diameter reduction rate (the amount of deformation due to the diameter reduction processing) at both axial end portions of the first outer tube bracket 20 is the diameter reduction at the axial central portion. In the first outer cylinder fitting 20 after the diameter reduction processing, both axial end portions thereof are smaller in diameter than the axial central portion. Further, in the present embodiment, the first outer tubular fitting 20 after the diameter reduction processing has a tapered shape in which both end portions in the axial direction gradually become smaller in diameter toward the outside in the axial direction, as shown in FIG. It has become.

  The main rubber elastic body 16 is formed with a pair of straight portions 26 that are opposed to each other in one radial direction. The straight portion 26 is formed to extend in the circumferential direction by a predetermined length and penetrate the main rubber elastic body 16 in the axial direction. Further, both end portions in the circumferential direction of the straight portion 26 are formed so as to extend toward the inner cylinder fitting 12 in the opposing direction of the pair of straight portions 26.

  Further, a central stopper rubber 28 is protruded from each of the pair of straight portions 26. The central stopper rubber 28 is integrally formed with the main rubber elastic body 16 and is provided so as to protrude in the radial direction from the inner cylinder fitting 12 side toward the first outer cylinder fitting 20 side. Further, the central stopper rubber 28 is projected radially outward from the axial central portion of the inner cylindrical metal member 12, and gradually becomes narrower in the axial direction toward the projecting tip side (outer peripheral side). Yes. Further, the central stopper rubber 28 is provided so as to protrude in the circumferential central portion of each of the straight portions 26 and gradually becomes narrower in the circumferential direction toward the protruding tip side. As described above, the central stopper rubber 28 has a shape that tapers toward the protruding tip side.

  Further, a central cushioning rubber layer 30 is formed on the inner peripheral surface of the first outer tubular fitting 20 in one radial direction, which is the direction in which the pair of curb portions 26 face each other. The central shock absorbing rubber layer 30 is configured by using a wall portion on the outer peripheral side of the straight portion 26 and is a thin rubber layer integrally formed with the main rubber elastic body 16. Thereby, the protruding front end surface of the central stopper rubber 28 is opposed to the central cushioning rubber layer 30 in the radial direction. Moreover, in this embodiment, the axial direction center part of the center shock absorbing rubber layer 30 is made thicker than the axial direction both ends.

  Further, shaft end buffer rubber layers 32 as buffer rubber layers are integrally formed on both sides in the axial direction of the main rubber elastic body 16. The shaft end cushioning rubber layer 32 has a thin, substantially cylindrical shape, protrudes from the inner peripheral portion of the main rubber elastic body 16 in the axial direction, and is vulcanized and bonded to the outer peripheral surface of the inner cylindrical metal member 12. . In particular, in the present embodiment, the outer peripheral surface of the shaft end cushioning rubber layer 32 is a cylindrical surface whose inner portion in the axial direction extends in parallel with the axial direction, and the outer portion in the axial direction gradually decreases in diameter toward the outer side in the axial direction. It is set as the taper surface which inclines with respect to an axial direction so that it may become.

  A separate stopper member 34 is disposed on the outer side in the radial direction of the shaft end cushioning rubber layer 32. The separate stopper member 34 is a substantially annular member as a whole, and is formed separately from the integrally vulcanized molded product 24. More specifically, the separate stopper member 34 is formed by providing a shaft end stopper rubber 38 on the inner peripheral surface of a fixed cylinder fitting 36 as a fixed cylinder member.

  The fixed cylinder fitting 36 has a thin-walled and large-diameter substantially cylindrical shape, and is formed of a metal material such as an aluminum alloy, for example. Further, in the present embodiment, the fixed barrel metal 36 is formed with a diameter that is substantially equal to the axial end portion diameter of the first outer barrel metal 20 after the first diameter reduction processing. In addition, the fixed cylindrical metal fitting 36 according to the present embodiment is formed with a recess that opens to the inner peripheral side in one radial direction and extends over the entire length in the axial direction. It is a stepped shape in the direction. Thereby, the thin part 40 which is thin compared with another part is formed in the part which the fixed cylinder metal fitting 36 opposes in one radial direction. The material for forming the fixed barrel metal 36 is not particularly limited, but it is desirable that the material be resistant to rust.

  In addition, the fixed tubular fitting 36 according to the present embodiment has an opening on the outer peripheral surface and continuously extends over the entire length in the axial direction on both sides in one radial direction substantially orthogonal to the opposing direction of the pair of thin portions 40. A pair of drain grooves 42 is formed. It should be noted that the fixed cylindrical fitting 36 is thinner than the other portions even at the portion where the drain groove 42 is formed.

  A pair of shaft end stopper rubbers 38 is provided on the inner peripheral surface of the fixed barrel metal 36. The shaft end stopper rubber 38 is formed so as to protrude radially inward from the inner peripheral surface of the fixed barrel metal 36, and a pair of shaft end stopper rubbers 38 are provided to face each other in one radial direction. In particular, in the present embodiment, a pair of shaft end stopper rubbers 38 is provided in one radial direction in which the pair of thin portions 40 oppose each other.

  Further, a concave portion 44 extending in the axial direction is formed in the central portion in the circumferential direction of the shaft end stopper rubber 38. The recess 44 is formed so as to open to an inner peripheral surface that is a protruding tip end surface of the shaft end stopper rubber 38, and has a cross-sectional shape that gradually expands inward in the radial direction. By forming such a recess 44, the protruding height in the radial direction of the shaft end stopper rubber 38 is changed in the circumferential direction. In this embodiment, the protruding tip surface of the shaft end stopper rubber 38 is The shape is stepped in the circumferential direction. The shaft end stopper rubber 38 is divided into two in the circumferential direction with the concave portion 44 interposed therebetween, and both circumferential portions on both sides of the concave portion 44 are protruded in the radial direction as contact portions 46. ing.

  In the present embodiment, buffer protrusions 47 are integrally formed as a large number of small protrusions on the protruding front end surface of the contact portion 46. The buffer ridges 47 are formed so as to extend in a circumferential direction with a predetermined length in a substantially constant semicircular cross section, and a large number of buffer ridges 47 separated by a predetermined distance in the axial direction are substantially parallel to each other. It is formed without. Thereby, the protrusion front end surface of the contact part 46 which concerns on this embodiment is made into the wave-like uneven | corrugated shape as a whole. In the present embodiment, the protrusion tip of the contact portion 46 has an uneven shape by providing a large number of buffer protrusions 47 in the axial direction on the protrusion tip surface of the contact portion 46 so as to be substantially parallel to each other. However, for example, by preparing a protrusion having a substantially constant semicircular shape extending in a circumferential direction with a predetermined length as a separate member from the shaft end stopper rubber, the protrusion of the abutting portion can be formed by bonding the protrusion. The protrusion tip surface of the contact portion can be formed into an uneven shape by being fixed to the protrusion tip.

  In the present embodiment, the pair of shaft end stopper rubbers 38 provided on both sides in the radial direction are connected to each other by a connecting portion 48. The connecting portion 48 is formed of a thin rubber elastic body, and is formed so as to be fixed to the inner peripheral surface of the fixed barrel metal 36 and extend in the circumferential direction. In addition, a pair of connecting portions 48 are provided between the circumferential directions of the pair of shaft end stopper rubbers 38, and the shaft end stopper rubbers 38 are connected to each other in the circumferential direction by the connecting portions 48. In particular, in the present embodiment, the pair of shaft end stopper rubbers 38 and the pair of connecting portions 48 are integrally formed and have a substantially annular shape as a whole.

  The separate stopper member 34 having such a structure is arranged on both sides in the axial direction of the first outer tubular fitting 20 on the same central axis as the first outer tubular fitting 20 constituting the integrally vulcanized molded product 24. Established. Further, the integrally vulcanized molded product 24 and the separate stopper member 34 of the main rubber elastic body 16 are arranged in the circumferential direction so that the radial direction in which the central stopper rubber 28 protrudes coincides with the radial direction in which the shaft end stopper rubber 38 protrudes. It is positioned. Then, the integrally vulcanized molded product 24 and the separate stopper member 34 of the main rubber elastic body 16 are held in a state of being positioned in the axial direction and the circumferential direction by being set on a jig. Note that the separate stopper member 34 in the present embodiment has a plane-symmetric shape with a virtual plane extending in the direction perpendicular to the axis at the center in the axial direction as a plane of symmetry, and when set on a jig, The orientation is not a problem.

  The integrated vulcanized molded product 24 after the first diameter reduction processing and the separate stopper member 34 are positioned as described above, and the integrated vulcanized molded product 24 of the main rubber elastic body 16 includes the second vulcanized molded product 24. The outer cylinder fitting 22 is extrapolated. The second outer cylinder fitting 22 has a cylindrical shape that is thinner and larger in diameter than the axially central portion of the first outer cylinder fitting 20, and is formed of a metal material such as iron, for example. The second outer cylinder fitting 22 has a larger axial dimension than the first outer cylinder fitting 20 and a smaller axial dimension than the inner cylinder fitting 12. Furthermore, in the present embodiment, the second outer cylinder fitting 22 is thicker than the first outer cylinder fitting 20. The material for forming the second outer cylinder fitting 22 is not particularly limited, but it is desirable that the second outer cylinder fitting 22 be selected so that deformation and damage are less likely to be a problem during press-fitting to the arm eye, which will be described later. Further, when the second outer cylinder fitting 22 is formed of a material that is relatively easy to rust such as iron as in the present embodiment, rust is generated by applying a known coating such as a cation coating. It is desirable to prevent this.

  Here, the second outer cylinder fitting 22 has an axial dimension larger than that of the first outer cylinder fitting 20, so that the second outer cylinder fitting 22 is arranged in the axial direction of the first outer cylinder fitting 20. Protruding on both sides. The separate stopper member 34 is arranged in an inserted state with respect to the axial end portion of the second outer cylinder fitting 22 positioned on the outer side in the axial direction than the first outer cylinder fitting 20. It has become.

  In the present embodiment, the first outer cylinder fitting 20 and the second outer cylinder fitting 22 are arranged such that the center in the axial direction is located on the same axial plane, and the second outer cylinder fitting 20 The cylinder fittings 22 are arranged so as to protrude at equal lengths on both sides in the axial direction of the first outer cylinder fitting 20. Furthermore, in this embodiment, the axially outer end surface of the fixed tubular fitting 36 of the separate stopper member 34 and the axial end surface of the second outer tubular fitting 22 are aligned in the axial direction on the same axial plane. It is located in.

  With the first outer cylinder fitting 20 and the fixed cylinder fitting 36 arranged on the inner peripheral side of the second outer cylinder fitting 22 in this way, Second diameter reduction is applied. Then, the inner peripheral surface of the second outer cylinder fitting 22 is pressed against the outer circumference of the first outer cylinder fitting 20 and the fixed cylinder fitting 36 from the outside in the radial direction. As a result, the second outer cylinder fitting 22 is externally fixed to the integral vulcanization molded product 24 of the main rubber elastic body 16 and the separate stopper member 34. As described above, the first outer cylinder fitting 20 and the second outer cylinder fitting 22 are fitted and fixed to each other to constitute the outer cylinder fitting 14 in the present embodiment, and at the same time, separate from the outer cylinder fitting 14 side. The body stopper member 34 can be fixedly provided. By the second diameter reduction processing, the second outer cylindrical fitting 22 is deformed to be larger at both axial end portions than at the axial central portion, so that the axial outer end portions are more deformed than the axial central portion. Has a small diameter.

  In this assembled state, the first outer cylinder fitting 20 constituting the integral vulcanization molded product 24 of the main rubber elastic body 16 is fitted and fixed to the substantially central portion in the axial direction of the second outer cylinder fitting 22. . Further, the separate stopper member 34 is provided on both sides so as to sandwich the first outer cylinder fitting 20 in the axial direction, and is disposed at a predetermined distance on the outer peripheral side of both axial ends of the inner cylinder fitting 12. Has been. Further, the shaft end stopper rubber 38 is protruded so as to face the shaft end buffer rubber layer 32 vulcanized and bonded to both end portions in the axial direction of the inner cylindrical metal member 12 with a predetermined distance in the radial direction. The shaft end stopper rubber 38 is brought into contact with the inner cylinder fitting 12 through the shaft end shock absorbing rubber layer 32 when the inner cylinder fitting 12 and the outer cylinder fitting 14 described later are relatively displaced.

  In addition, under the assembled state of the separate stopper member 34, the shaft end cushioning rubber layer 32 is formed so as to extend outward in the axial direction from the axially outer end portion of the shaft end stopper rubber 38. Furthermore, in this embodiment, the boundary between the tapered portion provided in the axially outer portion of the shaft end cushioning rubber layer 32 and the cylindrical portion provided in the axially inner portion of the shaft end cushioning rubber layer 32 is the shaft end. The stopper rubber 38 is positioned so as to face the intermediate portion in the radial direction in the radial direction. In the present embodiment, the radial separation between the central stopper rubber 28 and the central cushioning rubber layer 30 and the radial separation between the shaft end stopper rubber 38 and the axial cushioning rubber layer 32 are substantially equal. Has been.

  In the automotive strut arm bushing 10 according to the present embodiment having such a structure, the second outer cylinder fitting 22 is reduced in diameter to the second outer cylinder fitting 22 so that the second outer cylinder fitting 22 becomes the fixed cylinder fitting 36. On the other hand, the separate stopper member 34 is pressed against the second outer cylinder fitting 22 by being pressed from the radially outer side over the entire circumference. Therefore, it is possible to easily assemble the separate stopper member 34 while avoiding the problem that it is difficult to assemble the separate stopper member 34 due to dimensional errors or the like of the inner and outer cylinder fittings 12 and 14 and the fixed barrel fitting 36.

  Further, before the second outer cylinder fitting 22 is assembled, the first outer cylinder fitting 20 is subjected to a first diameter reduction process to relieve the tensile stress of the main rubber elastic body 16. Therefore, the first diameter reduction processing that requires a large amount of diameter reduction for sufficient pre-compression of the main rubber elastic body 16 can be realized with a relatively small force. In particular, in the present embodiment, since the first outer cylinder fitting 20 is thinner than the second outer cylinder fitting 22, the first diameter reduction processing can be realized more advantageously.

  Further, in the bush 10 according to the present embodiment, the central stopper rubber 28 and the shaft end stopper rubber 38 have a shape protruding in a specific radial direction, and these central stopper rubbers 28 with respect to the main axial direct load input direction. In addition, the protruding direction of the shaft end stopper rubber 38 needs to be aligned. Therefore, in the present embodiment, the integrally vulcanized molded product 24 of the main rubber elastic body 16 and the separate stopper member 34 are positioned and held with each other by a jig, and are inserted into the second outer cylinder fitting 22 in such a positioned state. Fit. As a result, it is possible to easily and highly accurately align the center stopper rubber 28 and the shaft end stopper rubber 38 in the circumferential direction. Therefore, the intended buffering stopper effect can be stably and effectively realized.

  Further, in the present embodiment, the inner cylinder fitting 12, the first outer cylinder fitting 20, and the fixed cylinder fitting 36 are all made of a rust-resistant aluminum alloy, and the second outer cylinder fitting 22 made of iron has Cationic coating is applied, and these metal fittings can be advantageously prevented from rusting. In addition, the fixed cylinder fitting 36 is fixedly assembled to the second outer cylinder fitting 22 when the second outer cylinder fitting 22 is brought into close contact with the outer side in the radial direction. Therefore, the separate stopper member 34 can be assembled to the second outer cylinder fitting 22 regardless of the material difference between the second outer cylinder fitting 22 and the fixed cylinder fitting 36.

  Furthermore, in this embodiment, the water draining groove 42 is formed so as to open on the outer peripheral surface of the fixed barrel metal 36, and water can be discharged to the outside through the water draining groove 42.

  The automotive strut arm bush 10 according to the present embodiment is, for example, a double wishbone suspension that constitutes a suspension mechanism for a steered wheel (front wheel), and a pair of lower arms are connected to a hub carrier as a carrier. It is suitably used for a suspension having a double joint structure. Such a double joint type suspension has a well-known structure shown in, for example, Japanese Patent Laid-Open Nos. 6-106932 and 2003-136927, and a detailed description thereof will be omitted. And a plurality of suspension members disposed between a hub carrier having a kingpin and a vehicle body.

  Specifically, as schematically shown in FIG. 7, the lower arm includes a pair of suspension arms including a first lower arm 18 and a second lower arm 50 that are spaced apart in the vehicle longitudinal direction. One end of 18, 50 is connected to a hub carrier (not shown) via a ball joint.

  In particular, in the present embodiment, the first lower arm 18 is disposed in front of the vehicle with respect to the second lower arm 50, and the mounting position of the second lower arm 50 with respect to the carrier is approximately the center of the wheel 52 (the axle and the axle) in plan view. And the mounting position of the first lower arm 18 with respect to the carrier is positioned in front of the vehicle out of the center of the wheel 52. The second lower arm 50 extends substantially in the lateral direction of the vehicle (the vehicle width direction or the axle direction and the left-right direction in FIG. 7), and the first lower arm 18 extends in the vehicle longitudinal direction. Inclined and extended at a predetermined angle with respect to the vehicle width direction.

  Furthermore, an arm eye 54 (see FIG. 1) as an attachment part to the vehicle body side is formed at the other end of each of the first lower arm 18 and the second lower arm 50. In the present embodiment, the first and second lower arms 18 and 50 may have curved shapes or the like, but in FIG. 7, the arm central axes are simply illustrated. Note that the arm central axis is a line in the lower arms 18 and 50 in which the attachment position to the carrier at one end portion in the longitudinal direction and the attachment position to the vehicle body at the other end portion in the longitudinal direction are connected by a straight line. Shall. The vehicle body may be a sub-frame such as a suspension frame in addition to the body body (main frame).

  Further, in the bush 10 according to the present embodiment, the outer cylinder fitting 14 is press-fitted into an arm eye 54 provided at the end of the first lower arm 18, and the first lower arm 18 is substantially in the center in the axial direction of the outer cylinder fitting 14. It is fitted and fixed in a state of being positioned at the part. In the present embodiment, the bush 10 is mounted so that the central axis of the bush 10 (the central axis of the inner and outer cylinder fittings 12 and 14) is orthogonal to the arm central axis of the first lower arm 18. The bush 10 is mounted on the automobile such that its central axis extends in a substantially horizontal direction.

  Note that when the outer cylinder fitting 14 (the first outer cylinder fitting 20 and the second outer cylinder fitting 22) is subjected to diameter reduction processing, the diameter reduction ratio (deformation amount) at both axial end portions is larger than the axial central portion. The outer diameter dimension of both end portions in the axial direction of the second outer cylinder fitting 22 is smaller than the outer diameter dimension of the central portion in the axial direction. As a result, when the bush 10 is mounted on the arm eye 54, both end portions in the axial direction of the second outer cylinder fitting 22 are not in contact with the arm eye 54, and the central portion in the axial direction is press-fitted into the arm eye 54. Thus, the bush 10 is fitted and fixed to the arm eye 54. Therefore, it is possible to prevent the peeling of the paint on the outer peripheral surface of both end portions in the axial direction of the second outer cylinder fitting 22 from being scratched, and to prevent the second outer cylinder fitting 22 from being caused by the peeling of the paint. Problems such as rust can be prevented. In the present embodiment, both end portions in the axial direction of the second outer cylinder fitting 22 are spaced radially inward with respect to the inner peripheral surface of the arm eye 54 and protruded from the arm eye 54 in the axial direction. As a result, both end portions in the axial direction of the second outer tubular fitting 22 are separated from the arm eye 54.

  Furthermore, the bush 10 according to the present embodiment is mounted such that the arm eye 54 is positioned at the center portion in the axial direction of the outer cylinder fitting 14, and the arm eye 54 is attached to the first outer cylinder fitting 20 and the second outer cylinder fitting. 22 is positioned in the overlapped portion. Therefore, by press-fitting a relatively high rigidity portion of the outer cylinder fitting 14 into the arm eye 54, it is possible to advantageously prevent deformation of the outer cylinder fitting 14 due to the press-fitting into the arm eye 54.

  Further, the inner cylinder fitting 12 of the bush 10 is fixed to a vehicle body side member through a fixing bolt (not shown) inserted through the inner hole. Particularly in the present embodiment, one direction (vertical direction in FIG. 2) perpendicular to the axis of the bush 10 provided with each pair of the straight portions 26, the central stopper rubber 28, and the shaft end stopper rubber 38 is the direction in which the arm central axis extends. It is assembled to become.

  As shown in FIG. 2, the bush 10 according to the present embodiment is configured so that the inner cylinder fitting 12 and the outer cylinder fitting 14 are arranged in one radial direction (in FIG. ) Is eccentric. When the bush 10 is attached to the vehicle, a static load is exerted on the bush 10 in one radial direction (downward in FIG. 2), and the inner cylinder fitting 12 and the outer cylinder fitting 14 are relatively moved. The inner cylinder fitting 12 and the outer cylinder fitting 14 are positioned on the same central axis by being displaced.

  Thus, the first lower arm 18 and the second lower arm 50 are independent of each other based on the displacement of the ball joint and the elastic deformation of the main rubber elastic body 16 in the bush 10 between the hub carrier and the vehicle body side member. The steering wheel is suspended from the vehicle body via a plurality of suspension members including the lower arms 18 and 50. The first lower arm 18 connected to the vehicle body via the strut arm bush 10 extends at a predetermined angle with respect to the vehicle front-rear direction to support the force of the suspension in the vehicle front-rear direction. Become.

  In such a state in which the bush 10 is mounted on the vehicle, the wheel 52 is directed substantially in the front-rear direction under the normal traveling state of the vehicle, and a load such as overcoming a step input in this state is a substantial axis of the strut arm 18. Since it is exerted in the direction, it is exerted on the bush 10 as a load in a direction substantially perpendicular to the axis. At this time, in the strut arm bush 10 having the structure according to the present embodiment, a pair of straight portions 26 are provided in one direction perpendicular to the axis that is the axial direction of the strut arm 18, thereby realizing a good riding comfort. It has become so.

  The bush 10 is provided with a stopper mechanism in the axial direction of the strut arm 18. That is, in the bush 10, a pair of central stopper rubber 28 and shaft end stopper rubbers 38, 38 are provided in the axial direction of the strut arm 18. When the inner cylinder fitting 12 and the outer cylinder fitting 14 are relatively displaced in the direction perpendicular to the axis, as shown in FIG. 8, the inner cylinder fitting 12 and the outer cylinder fitting 14 are connected to the central stopper rubber 28 and the shaft. The end stopper rubber 38 is adapted to abut against the buffer. Thereby, the relative displacement of the inner cylinder fitting 12 and the outer cylinder fitting 14 in the direction perpendicular to the axis is limited in a buffering manner, so that both good riding comfort and excellent durability are realized.

  In the present embodiment, when the inner cylinder fitting 12 and the outer cylinder fitting 14 are relatively displaced in the direction perpendicular to the axis, the central stopper rubber 28 and the central cushioning rubber layer 30 become the shaft end stopper rubber 38 and the shaft end cushioning rubber layer. Compared to 32, it can be brought into contact at the same time or slightly first. Further, since the central stopper rubber 28 has a tapered shape, the contact surface with the central cushioning rubber layer 30 becomes larger as the central stopper rubber 28 is deformed. Accordingly, a buffering stopper effect can be advantageously obtained, and effective displacement limitation can be realized at the same time.

  Further, the axial end stopper rubber 38 is partially overlapped with a cylindrical surface formed on the axially inner side portion of the axial end cushioning rubber layer 32 in the projection perpendicular to the axial direction. In addition, the shaft end shock absorbing rubber layer 32 is brought into contact with the inner cylinder fitting 12 and the outer cylinder fitting 14 by the relative displacement in the direction perpendicular to the axis. On the other hand, the axially outer portion of the shaft end stopper rubber 38 is positioned at a position where the cylindrical surface formed on the axially inner portion of the shaft end cushioning rubber layer 32 is displaced outward in the axial direction. Thereby, the contact area of the shaft end stopper rubber 38 with respect to the shaft end buffer rubber layer 32 is reduced, and a buffering stopper effect is realized.

  Furthermore, the shaft end stopper rubber 38 in the present embodiment is provided with a recess 44 in the central portion in the circumferential direction, so that the surface abutted against the inner cylindrical metal member 12 is inclined with respect to the main load input direction. . Therefore, the input load is applied in a direction inclined with respect to the contact surface (the outer peripheral surface of the contact portion 46), and the contact portion 46 undergoes shear deformation together with compression deformation. As a result, the spring characteristic of the abutting portion 46 becomes relatively soft when abutting by load input in the direction perpendicular to the axis, and a buffering stopper effect can be advantageously realized.

  Furthermore, the protruding tip end surface of the abutting portion 46 of the shaft end stopper rubber 38 has a wavy uneven shape, so that the abutting portion 46 can be abutted more buffered. Furthermore, when the abutting portion 46 abuts against the inner cylindrical metal fitting 12, it is possible to reduce noise generated by rubbing the abutting portion 46 and the shaft end shock absorbing rubber layer 32.

  Further, when the wheel 52 is tilted with respect to the front-rear direction by a steering operation or the like, the strut arm 18 is tilted, and the outer cylinder fitting 14 is displaced with respect to the inner cylinder fitting 12 in the twisting direction. When the inner cylinder fitting 12 and the outer cylinder fitting 14 are displaced relative to each other in the twisting direction, the shaft end stopper rubber 38 contacts the inner cylinder fitting 12 via the shaft end cushioning rubber layer 32 as shown in FIG. It can be touched. As a result, the relative displacement of the inner cylinder fitting 12 and the outer cylinder fitting 14 in the twisting direction is limited, and excessive tilting of the strut arm 18 can be prevented. Therefore, it is possible to prevent the turning angle of the wheel 52 from becoming excessive with respect to the steering operation amount, and to improve the steering stability advantageously.

  In the present embodiment, the outer peripheral surface of the axially outer portion of the shaft end cushioning rubber layer 32 is a tapered surface that is inclined at an angle corresponding to the maximum twist angle of the inner cylinder fitting 12 and the outer cylinder fitting 14. When the shaft end stopper rubber 38 and the shaft end shock absorbing rubber layer 32 come into contact with each other due to the relative displacement in the twisting direction of the outer cylinder fitting 12 and the outer cylinder fitting 14, the contact surfaces of the shaft end stopper rubber 38 and the shaft end shock absorbing rubber layer 32 are They are designed to be parallel to each other. Therefore, when the shaft end stopper rubber 38 and the shaft end cushioning rubber layer 32 are in contact with each other in the twisting direction, the relative displacement between the inner cylinder fitting 12 and the outer cylinder fitting 14 is more advantageously limited by increasing the contact area. You can do that.

  As mentioned above, although one Embodiment of this invention was described, this is an illustration to the last, Comprising: This invention is not interpreted restrictively at all by the specific description in this Embodiment.

  For example, in the above-described embodiment, the protruding front end surface of the abutting portion 46 of the shaft end stopper rubber 38 is formed so as to extend in parallel with the central axis of the outer cylinder fitting 14, but outward in the axial direction. You may comprise the inclined surface which inclines gradually to radial direction outward. In addition, when employ | adopting the shaft end stopper rubber of such a structure, it is desirable to comprise a shaft end buffer rubber layer with the cylindrical surface extended in parallel with an axial direction. By adopting such a shaft end stopper rubber and a shaft end cushioning rubber layer, both the buffer stopper effect in the direction perpendicular to the axis and the reliable stopper effect in the twisting direction are compatible, as in the above embodiment. Can be realized.

  Further, the structure of the shaft end stopper rubber 38 is not limited to that described in the embodiment. Specifically, for example, the shaft end stopper rubbers 38 are not necessarily connected to each other by the connecting portion 48 to have an annular shape as a whole, and the pair of shaft end stopper rubbers 38 are independently formed. May be. Further, for example, the recess 44 may not be provided, and the shaft end stopper rubber 38 does not need to be divided into the two contact portions 46 by the recess 44.

  Further, the shaft end stopper rubber 38 does not need to be configured such that only the abutting portion 46 abuts on the inner cylindrical metal member 12 side. For example, when the abutting portion 46 is deformed to a predetermined amount or more, the concave portion The bottom wall portion 44 may be brought into contact with the inner cylinder fitting 12. According to this, since the bottom wall part of the recessed part 44 formed with the thin rubber elastic body compared with the contact part 46 contact | abuts to the inner cylinder metal fitting 12, a more reliable stopper effect can be exhibited.

  In addition, the materials of the inner and outer cylinder fittings 12 and 14 and the fixed barrel fitting 36 shown in the above embodiment are merely examples, and are not construed as limiting in any way. In addition, as a material for forming the inner and outer cylinder fittings 12 and 14 and the fixed cylinder fitting 36, a material which does not easily rust is preferably used. Moreover, in the said embodiment, although the cation coating was given to the 2nd outer cylinder metal fitting 22, the cation coating was shown also with respect to the inner cylinder metal fitting 12, the 1st outer cylinder metal fitting 20, and the fixed cylinder metal fitting 36. Various known coatings such as coating can be appropriately applied to advantageously improve durability against rust and corrosion.

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

It is a longitudinal cross-sectional view which shows the strut arm bush for motor vehicles as one Embodiment of this invention, Comprising: The II sectional view taken on the line in FIG. The front view which shows the strut arm bush shown by FIG. It is a longitudinal cross-sectional view which shows the integral vulcanization molded product which comprises the strut arm bush shown by FIG. 1, Comprising: The III-III sectional view taken on the line in FIG. The front view which shows the integral vulcanization molded product shown by FIG. It is a longitudinal cross-sectional view which shows the after-drawing process of the integrally vulcanized molded product shown by FIG. 3, Comprising: The VV sectional view taken on the line in FIG. FIG. 6 is a front view showing a state after drawing of the integrally vulcanized molded product shown in FIG. 5. Schematic which shows the double joint type suspension with which the strut arm bush shown by FIG. 1 is applied. The strut arm bush shown in FIG. 1 is an explanatory view showing the contact state of the stopper rubber when a load perpendicular to the axis is inputted. The strut arm bush shown in FIG. 1 is an explanatory view showing the contact state of the shaft end stopper rubber when a load in the twisting direction is input.

Explanation of symbols

10: Strut arm bush for automobile, 12: Inner tube bracket, 14: Outer tube bracket, 16: Rubber elastic body, 18: Strut arm, 20: First outer tube bracket, 22: Second outer tube bracket, 24: integrally vulcanized molded product, 32: shaft end cushioning rubber layer, 34: separate stopper member, 36: fixed barrel metal fitting, 38: shaft end stopper rubber, 44: recess, 54: arm eye

Claims (8)

In the cylindrical vibration isolator that connects the inner shaft member and the outer cylindrical member that is spaced apart on the outer peripheral side thereof by a main rubber elastic body,
The inner shaft member and the first outer cylinder member spaced apart on the outer peripheral side thereof are connected by the main rubber elastic body to form a cylindrical vibration isolator body, and from the fixed cylinder member and the fixed cylinder member A shaft end stopper member including a shaft end stopper rubber projecting toward the inner peripheral side is disposed on each side in the axial direction of the vibration isolator main body, and further, the vibration isolator main body and the shaft end stopper The first outer cylinder member and the second outer cylinder member are fitted by disposing a member on the inner peripheral side of the second outer cylinder member and subjecting the second outer cylinder member to a diameter reduction process. The outer cylinder member is configured by being fixedly attached, and the shaft end stopper member is assembled to the outer cylinder member so that the inner shaft member and the outer cylinder member are connected to each other through the shaft end stopper rubber. Cylindrical anti-vibration characterized by being able to abut with Location.   2. The protrusion height of the shaft end stopper rubber is changed in the circumferential direction by forming a recess extending in the axial direction at the projecting top portions on the inner peripheral side of the shaft end stopper rubber on both sides in the axial direct load input direction. Cylindrical anti-vibration device.   A buffer rubber layer is deposited on a portion of the inner shaft member where the shaft end stopper rubber is brought into contact, and at least one of the contact surfaces of the shaft end stopper rubber and the buffer rubber layer is formed on the inner shaft member. When the shaft end stopper rubber and the buffer rubber layer are brought into contact with each other by the relative displacement in the twisting direction of the inner shaft member and the outer cylindrical member, the shaft end stopper rubber is inclined with respect to the central axis. The cylindrical vibration isolator according to claim 1 or 2, wherein the contact surfaces of the shock absorbing rubber layer are parallel to each other.   The cylindrical vibration isolator according to any one of claims 1 to 3, wherein a large number of small protrusions are integrally formed on a contact surface of the shaft end stopper rubber.   The cylindrical vibration isolator as described in any one of Claims 1 thru | or 4 employ | adopted as a strut arm bush attached to the attachment site | part to the vehicle body side of a suspension arm.   The overlapping part of the second outer cylinder member with the first outer cylinder member in the axially intermediate part of the second outer cylinder member is press-fitted into the vibration isolation target member, and both axial end portions of the second outer cylinder member are The cylindrical vibration isolator as described in any one of Claims 1 thru | or 5 arrange | positioned spaced apart from the vibration isolator object member.   Both end portions in the axial direction of the second outer cylinder member have a smaller diameter than the intermediate portion in the axial direction, and both end portions in the axial direction of the second outer cylinder member are spaced apart from the vibration-proof target member. The cylindrical vibration isolator according to any one of claims 1 to 6, wherein an intermediate portion in the axial direction of the second outer cylinder member is press-fitted into the vibration isolation target member. A cylindrical anti-vibration device body is prepared in which a first outer cylinder member is disposed apart from the outer peripheral side of the inner shaft member, and the inner shaft member and the first outer cylinder member are connected by a rubber elastic body. And a process of
A step of reducing the diameter of the first outer cylinder member in the vibration isolator main body and pre-compressing the main rubber elastic body;
A shaft end stopper in which a shaft end stopper rubber is fixed to a portion facing in one radial direction on the inner peripheral surface of a cylindrical fixed cylindrical member, and the shaft end stopper rubber is protruded toward the inner peripheral side in one radial direction. Preparing a member;
The shaft end stopper members are disposed on both sides in the axial direction of the vibration isolator main body, and a second outer cylinder member is extrapolated to the vibration isolator main body and the shaft end stopper member. A method of manufacturing a cylindrical vibration isolator, comprising the step of assembling the vibration isolator body and the shaft end stopper member to the second outer cylinder member by subjecting the member to a diameter reduction process.

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