Anti-vibration device

Abstract

To provide a vibration control device of a new structure capable of easily and properly assembling a vibration control device main body and an outer member while preventing slipping-off of the vibration control device main body from the outer member, in the non-adhesion type vibration control device.SOLUTION: In a vibration control device 10 in which a vibration control device main body 12 configured by fixing a main body rubber elastic body 18 to an inner shaft member 16, is inserted to a cylindrical portion 34 of an outer member 14 to be assembled in a non-adhesion state, rubber arm portions 28, 28 of the main body rubber elastic body 18 are pre-compressed between the inner shaft member 16 and the cylindrical portion 34, first anti-slipping-off pieces 42 projecting to an inner periphery are integrally formed on opening portions at axial both sides of the cylindrical portion 34, and a first anti-slipping-off portion for preventing slipping-off of the vibration control device main body 12 from the cylindrical portion 34 is configured by contact of the first anti-slipping-off pierces 42 and the rubber arm portions 28, 28. The opening portion at least at one side of the cylindrical portion 34 is provided with a plurality of first anti-slipping-off pieces 42a, 42a overlapped to one rubber arm portion 28 in a state of being separated from each other in a circumferential direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an anti-vibration device that can be applied, for example, to torque rods, engine mounts, suspension links, etc. of automobiles, and in particular to a non-bonded type anti-vibration device in which a main rubber elastic body is pressed into an outer member and assembled without bonding. [Background technology]

[0002] Conventionally, there has been known an anti-vibration device used for anti-vibration connection between a vibration source such as a power unit and an object to be anti-vibration such as a vehicle body in a vehicle, etc. Anti-vibration devices are generally of an adhesive type in which an inner shaft member and an outer member are adhered to a main rubber elastic body, but as shown in JP 2008-082517 A (Patent Document 1), for example, an anti-vibration device main body having a structure in which legs of an elastic member extend from an inner tube is press-fitted into an outer tube to be assembled without adhesive.

[0003] Adhesive-type vibration-damping devices are able to withstand large input loads because the inner shaft member and outer member are firmly attached to the main rubber elastomer body. However, because the main rubber elastomer body is attached to both the inner shaft member and the outer member, tensile stress is likely to act on the main rubber elastomer body, and peeling due to stress concentration on the adhesive surface can become a problem, making it necessary to improve durability and load-bearing capacity.

[0004] Therefore, non-bonded vibration isolation devices have been studied based on a design concept different from that of bonded vibration isolation devices that use bonding to achieve high load-bearing performance. In non-bonded vibration isolation devices, the main rubber elastic body is not bonded to the outer member, so that when an input is applied that generates tensile stress in the main rubber elastic body in bonded types, the main rubber elastic body separates from the outer member, thereby significantly reducing the generation of tensile stress in the main rubber elastic body. Therefore, in non-bonded vibration isolation devices, the durability of the main rubber elastic body is advantageously ensured, and problems such as peeling of the adhesive surface between the inner shaft member and the main rubber elastic body are unlikely to occur. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2008-082517 A Summary of the Invention [Problem to be solved by the invention]

[0006] In a non-bonded vibration-proof device, since the main rubber elastic body is displaceable relative to the outer member, a stop structure may be provided to prevent the main rubber elastic body from coming off the outer member. In Patent Document 1, side plates that protrude toward the inner circumference on both axial sides of the outer tube are provided as stoppers. The side plates are provided so as to cover the entire extending end of the leg of the elastic member, and the abutment between the side plates and the leg prevents the leg from coming off the outer tube.

[0007] In addition, in a non-adhesive type vibration isolation device, the main rubber elastic body is pressed into the outer member in a radially pre-compressed state in order to prevent the main rubber elastic body from coming off the outer member due to frictional resistance by abutting against the outer member in an initial state. Specifically, for example, the main rubber elastic body is compressed by a jig to reduce its diameter and inserted into the outer member, whereby the main rubber elastic body expands in diameter due to elastic shape restoration on the inner circumference of the outer member and abuts against the inner peripheral surface of the outer member. At this time, the main rubber elastic body is pressed against the inner peripheral surface of the outer member in a compressed state without restoring to its initial shape, so that the main rubber elastic body is assembled to the outer member in a pre-compressed state.

[0008] However, when the main rubber elastic body is pre-compressed and assembled to an outer member equipped with a stopper, the assembled state of the main rubber elastic body to the outer member may be unstable. That is, when the main rubber elastic body is inserted into the outer member in a compressed state and elastically restores its shape on the inner circumference of the outer member, the abutment state of the main rubber elastic body and the stopper may vary due to, for example, dimensional errors of the main rubber elastic body and the outer member, or errors in the relative positions of the main rubber elastic body and the outer member in the axial direction. As a result, the main rubber elastic body may be assembled to the outer member in a distorted state, or the main rubber elastic body may get caught on the stopper and not be pressed properly against the inner circumference of the outer member, which may cause problems such as a decrease in the durability and pull-out resistance of the main rubber elastic body and a negative effect on vibration-proofing performance.

[0009] In Patent Document 1, the side plate portion constituting the stopper is separate from the outer tube to which the elastic member is attached, and for example, the side plate portion is fixed to the outer tube with the elastic member pressed into the outer tube, thereby providing the stopper on both axial sides of the elastic member. However, such a structure in Patent Document 1 leads to an increase in the number of parts, and requires fixing the outer tube and the side plate portion by means of welding or the like with the elastic member attached to the outer tube, which increases the number of work steps required for manufacturing and may cause adverse effects on the elastic member due to heat during welding. In addition, even if the elastic member is pressed into the outer tube and then the side plate portion provides the stopper, there is a risk that the elastic member may get caught when the side plate portion is fixed to the outer tube, or that the axial positions of the elastic member and the side plate portion may vary, making it difficult to stably assemble the elastic member to the outer member consisting of the outer tube and the side plate portion.

[0010] The problem to be solved by the present invention is to provide a vibration-damping device of a new structure that can effectively prevent the vibration-damping device main body from coming loose from the outer member, which is a problem specific to non-bonded type vibration-damping devices, while easily achieving appropriate assembly of the vibration-damping device main body and outer member, which are assembled without bonding. [Means for solving the problem]

[0011] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely illustrative and may be combined with one another as appropriate, and the multiple components described in each embodiment may be recognized and used independently as far as possible, and may also be combined with any of the components described in another embodiment as appropriate. As a result, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0012] In a first aspect, in a vibration-proof device in which an anti-vibration device main body having a structure in which a main rubber elastic body is fixed to the outer peripheral surface of an inner shaft member is inserted into a cylindrical portion of an outer member and assembled in a non-adhesive state, the inner shaft member and the outer member are elastically connected by the main rubber elastic body, the main rubber elastic body has a plurality of rubber arm portions which mutually connect the inner shaft member and the cylindrical portion of the outer member, the plurality of rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, and the cylindrical portion A first retaining piece is integrally formed in the openings on both axial sides of the cylindrical portion at a position corresponding to the rubber arm portion in the circumferential direction, and a first retaining piece that prevents the vibration isolator body from coming off the cylindrical portion is formed by the abutment of the first retaining piece and the rubber arm portion, and a plurality of the first retaining pieces are provided at a distance from each other in the circumferential direction of the cylindrical portion in at least one of the openings of the cylindrical portion, and the plurality of first retaining pieces are overlapped with the rubber arm portion in the axial direction. On the other hand, the first retaining piece on one axial side of the tubular portion and the first retaining piece on the other axial side are formed at different positions in the circumferential direction of the tubular portion and are arranged without overlapping with each other when projected in the axial direction, the first retaining piece on one axial side is provided at a position corresponding to a central portion of the rubber arm portion in the circumferential direction of the tubular portion, and the first retaining piece on the other axial side is provided on both sides in the circumferential direction of the tubular portion with respect to the first retaining piece on one axial side, and the sum of the overlapping areas of the first retaining piece on the other axial side and the rubber arm portion is larger than the sum of the overlapping areas of the first retaining piece on one axial side and the rubber arm portion. It is something.

[0013] The anti-vibration device constructed according to this embodiment is a non-adhesive type anti-vibration device in which the main rubber elastic body is assembled to the outer member in a non-adhesive state, so that the tensile stress generated in the main rubber elastic body when vibration is input is reduced, improving the durability of the main rubber elastic body. Also, by pre-compressing the main rubber elastic body, it is possible to further reduce the tensile stress and adjust the spring constant.

[0014] The first retaining pieces of the outer member and the rubber arm portions of the main rubber elastic body come into contact with each other, thereby preventing the vibration damping device main body from coming out of the tubular portion of the outer member, and enabling the vibration damping device main body to be stably held in an assembled state to the outer member. Since a plurality of first retaining pieces are provided at intervals in the circumferential direction in at least one of the openings of the tubular portion, it becomes easier to obtain a large total contact area between the rubber arm portions and the first retaining pieces, and since the contact points between the first retaining pieces and the rubber arm portions are distributed in the circumferential direction, prevention of the rubber arm portions from coming out by contact with the first retaining pieces is more effectively realized.

[0015] Furthermore, because the multiple first prevention pieces provided at at least one opening of the tubular portion are arranged spaced apart from one another in the circumferential direction, it is possible to visually check the state of the contact portion between the first prevention pieces and the rubber arm portion through the spaces between the multiple first prevention pieces, etc. This makes it easy to grasp the assembled state of the outer member and the main rubber elastic body, and allows the main rubber elastic body to be properly assembled to the outer member. Furthermore, with the vibration-proof device constructed according to this embodiment, an outer member having first retaining pieces protruding toward the inner circumference of the cylindrical portion provided at the open end on both axial sides of the cylindrical portion can be easily molded by a simple mold structure divided in the axial direction of the cylindrical portion. Preferably, the retaining portions on both axial sides have a shorter circumferential length than the outer periphery of the rubber arm portion, and two or more circumferential ends of the retaining portions are provided circumferentially spaced apart on the axial side surface of the rubber arm portion. This makes it easier and more accurate to check that the rubber arm portion is correctly assembled by fitting it axially inward of the retaining portions. In addition, with a vibration-damping device constructed in accordance with this embodiment, the first anti-pullout piece provided on one axial side is overlapped circumferentially with the central portion of the rubber arm portion, so that the contact reaction force acting on the rubber arm portion due to contact with the first anti-pullout piece is exerted on the rubber arm portion in a balanced manner, and the rubber arm portion can be efficiently prevented from coming loose to one axial side by the small first anti-pullout piece. In addition, the multiple first anti-pullout pieces provided on the other axial side are overlapped with the rubber arm portion at positions spaced apart from each other in the circumferential direction, thereby effectively preventing the vibration-damping device main body from coming off in the other axial direction with respect to the tubular portion. Moreover, the overlapping area of ​​the multiple first anti-pullout pieces provided on the other axial side with respect to the rubber arm portion is made larger than the overlapping area of ​​the first anti-pullout pieces provided on one axial side with respect to the rubber arm portion, so that the vibration-damping device main body is more effectively prevented from coming off in the other axial direction. Therefore, when the resistance against coming off required on both axial sides is different, such as when the axial force acting on the vibration-damping device main body is different in one axial direction and the other axial direction, it is possible to obtain effective resistance against coming off on both axial sides.

[0021] No. two The embodiment is First In the vibration-damping device described in this embodiment, the elastic main axis of the rubber arm portion extending in the connection direction between the inner shaft member and the tubular portion is inclined in the axial direction from the inner shaft member side toward the tubular portion side.

[0022] According to the vibration-isolating device constructed according to this embodiment, the vibration-isolating device body can be easily assembled to the outer member by considering the insertion direction of the vibration-isolating device body into the cylindrical portion, for example, by inserting the vibration-isolating device body into the cylindrical portion from the side with the smaller outer dimension of the rubber arm portion. Also, when an axial force is input, which expands the outer dimension of the inclined rubber arm portion, the frictional resistance acting between the rubber arm portion and the cylindrical portion increases due to the deformation of the rubber arm portion, and a large resistance force against the vibration-isolating device body coming out of the cylindrical portion can be obtained. Therefore, for example, when the maximum value of the axial load input between the inner shaft member and the outer member is different on both axial sides, the axial direction of the vibration-isolating device body can be set in consideration of the magnitude of the input load, thereby advantageously preventing the vibration-isolating device body from coming out of the cylindrical portion. In a third aspect, an anti-vibration device in which an anti-vibration device main body having a structure in which a main rubber elastic body is fixed to the outer peripheral surface of an inner shaft member is inserted into a cylindrical portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastic body, the main rubber elastic body has a plurality of rubber arm portions which interconnect the inner shaft member and the cylindrical portion of the outer member, the plurality of rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, and openings on both axial sides of the cylindrical portion have a plurality of rubber arm portions which are pre-compressed toward the inner circumference at positions corresponding to the rubber arm portions in the circumferential direction. A protruding first anti-slip piece is formed integrally with the rubber arm portion, and a first anti-slip piece is formed by abutting the first anti-slip piece with the rubber arm portion to prevent the vibration-damping device main body from coming out of the tubular portion, and a plurality of the first anti-slip pieces are provided at a distance from each other in the circumferential direction of the tubular portion at at least one of the openings of the tubular portion, and each of the multiple first anti-slip pieces is overlapped in the axial direction with respect to the rubber arm portion, and the elastic main axis of the rubber arm portion extending in the connection direction between the inner shaft member and the tubular portion is inclined in the axial direction from the inner shaft member side toward the tubular portion side. The anti-vibration device constructed according to this embodiment is a non-adhesive type anti-vibration device in which the main rubber elastic body is assembled to the outer member in a non-adhesive state, so that the tensile stress generated in the main rubber elastic body when vibration is input is reduced, improving the durability of the main rubber elastic body. Also, by pre-compressing the main rubber elastic body, it is possible to further reduce the tensile stress and adjust the spring constant. The first retaining pieces of the outer member and the rubber arm portions of the main rubber elastic body come into contact with each other, thereby preventing the vibration damping device main body from coming out of the tubular portion of the outer member, and enabling the vibration damping device main body to be stably held in an assembled state to the outer member. Since a plurality of first retaining pieces are provided at intervals in the circumferential direction in at least one of the openings of the tubular portion, it becomes easier to obtain a large total contact area between the rubber arm portions and the first retaining pieces, and since the contact points between the first retaining pieces and the rubber arm portions are distributed in the circumferential direction, prevention of the rubber arm portions from coming out by contact with the first retaining pieces is more effectively realized. Furthermore, because the multiple first prevention pieces provided at at least one opening of the tubular portion are arranged spaced apart from one another in the circumferential direction, it is possible to visually check the state of the contact portion between the first prevention pieces and the rubber arm portion through the spaces between the multiple first prevention pieces, etc. This makes it easy to grasp the assembled state of the outer member and the main rubber elastic body, and allows the main rubber elastic body to be properly assembled to the outer member. Furthermore, according to the vibration-isolating device constructed according to this embodiment, the vibration-isolating device body can be easily assembled to the outer member by considering the insertion direction of the vibration-isolating device body into the cylindrical portion, for example, by inserting the vibration-isolating device body into the cylindrical portion from the side with the smaller outer dimension of the rubber arm portion. Also, when an axial force is input, which expands the outer dimension of the inclined rubber arm portion, the frictional resistance acting between the rubber arm portion and the cylindrical portion increases due to the deformation of the rubber arm portion, and a large resistance force against the vibration-isolating device body coming out of the cylindrical portion can be obtained. Therefore, for example, when the maximum value of the axial load input between the inner shaft member and the outer member is different on both sides in the axial direction, the axial direction of the vibration-isolating device body can be set in consideration of the magnitude of the input load, thereby advantageously preventing the vibration-isolating device body from coming out of the cylindrical portion.

[0023] No. four The first to fourth aspects are threeIn the vibration-damping device described in any one of the above aspects, the main rubber elastic body is provided with a stopper protrusion protruding circumferentially between the multiple rubber arm portions from the inner shaft member toward the tubular portion, and a second anti-pullout piece protruding toward the inner circumference at a position corresponding to the stopper protrusion in the circumferential direction is integrally formed in at least one of the openings of the tubular portion, and a second anti-pullout piece is formed by abutment between the second anti-pullout piece and the stopper protrusion to prevent the vibration-damping device main body from coming off the tubular portion.

[0024] In a vibration-damping device constructed in accordance with this embodiment, the abutment between the stopper protrusion and the tubular portion limits the amount of relative displacement between the inner shaft member and the outer member in the direction perpendicular to the axis, thereby preventing excessive elastic deformation of the main rubber elastic body and improving the durability of the main rubber elastic body.

[0025] In addition, the vibration-damping device main body is prevented from coming out of the tubular portion not only by the first anti-slip portion formed by the abutment of the first anti-slip piece with the rubber arm portion, but also by the second anti-slip portion formed by the abutment of the second anti-slip piece with the stopper protrusion, thereby more effectively maintaining the proper assembly state of the vibration-damping device main body and the outer member. In a fifth aspect, in an anti-vibration device in which an anti-vibration device main body having a structure in which a main rubber elastic body is fixed to the outer peripheral surface of an inner shaft member is inserted into a cylindrical portion of an outer member and assembled in a non-adhesive state, the inner shaft member and the outer member are elastically connected by the main rubber elastic body, the main rubber elastic body has a plurality of rubber arm portions which interconnect the inner shaft member and the cylindrical portion of the outer member, the plurality of rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, first stop pieces are integrally formed at openings on both axial sides of the cylindrical portion and protrude inward at positions corresponding to the rubber arm portions in the circumferential direction, and the anti-vibration device main body is prevented from coming off from the cylindrical portion by the abutment of the first stop pieces and the rubber arm portions. a first anti-removal portion is formed to prevent the vibration-damping device main body from coming out of the cylindrical portion, and a plurality of first anti-removal pieces are provided at least in one of the openings of the cylindrical portion, spaced apart from each other in the circumferential direction of the cylindrical portion, and each of the plurality of first anti-removal pieces is overlapped in the axial direction with respect to the rubber arm portion, the main rubber elastic body has a stopper protrusion protruding from the inner shaft member toward the cylindrical portion between the plurality of rubber arm portions in the circumferential direction, and at least one of the openings of the cylindrical portion is integrally formed with a second anti-removal piece protruding toward the inner circumference at a position corresponding to the stopper protrusion in the circumferential direction, and a second anti-removal portion is formed to prevent the vibration-damping device main body from coming out of the cylindrical portion by abutment between the second anti-removal piece and the stopper protrusion. The anti-vibration device constructed according to this embodiment is a non-adhesive type anti-vibration device in which the main rubber elastic body is assembled to the outer member in a non-adhesive state, so that the tensile stress generated in the main rubber elastic body when vibration is input is reduced, improving the durability of the main rubber elastic body. Also, by pre-compressing the main rubber elastic body, it is possible to further reduce the tensile stress and adjust the spring constant. The first retaining pieces of the outer member and the rubber arm portions of the main rubber elastic body come into contact with each other, thereby preventing the vibration damping device main body from coming out of the tubular portion of the outer member, and enabling the vibration damping device main body to be stably held in an assembled state to the outer member. Since a plurality of first retaining pieces are provided at intervals in the circumferential direction in at least one of the openings of the tubular portion, it becomes easier to obtain a large total contact area between the rubber arm portions and the first retaining pieces, and since the contact points between the first retaining pieces and the rubber arm portions are distributed in the circumferential direction, prevention of the rubber arm portions from coming out by contact with the first retaining pieces is more effectively realized. Furthermore, because the multiple first prevention pieces provided at at least one opening of the tubular portion are arranged spaced apart from one another in the circumferential direction, it is possible to visually check the state of the contact portion between the first prevention pieces and the rubber arm portion through the spaces between the multiple first prevention pieces, etc. This makes it easy to grasp the assembled state of the outer member and the main rubber elastic body, and allows the main rubber elastic body to be properly assembled to the outer member. Furthermore, with an anti-vibration device constructed in accordance with this embodiment, the abutment between the stopper protrusion and the tubular portion limits the amount of relative displacement between the inner shaft member and the outer member in the direction perpendicular to the axis, thereby preventing excessive elastic deformation of the main rubber elastic body and improving the durability of the main rubber elastic body. In addition, the vibration-damping device main body is prevented from coming out of the tubular portion not only by the first anti-slip portion formed by the abutment of the first anti-slip piece with the rubber arm portion, but also by the second anti-slip portion formed by the abutment of the second anti-slip piece with the stopper protrusion, thereby more effectively maintaining the proper assembly state of the vibration-damping device main body and the outer member.

[0026] The sixth aspect is Four or Fifth attitude In the vibration-damping device described above, a pair of stopper protrusions protrude on both radial sides of the inner shank, and the second anti-detachment piece provided at a position corresponding to one of the stopper protrusions is formed on the opening side of one axial direction of the cylindrical portion relative to the one stopper protrusion, and the second anti-detachment piece provided at a position corresponding to the other stopper protrusion is formed on the opening side of the other axial direction of the cylindrical portion relative to the other stopper protrusion.

[0027] According to the vibration-damping device constructed in accordance with this embodiment, the second anti-removal piece is provided on one axial side of the stopper protrusion, so that when an outer member having the second anti-removal piece is molded, undercut in the axial direction by the second anti-removal piece is avoided, making it possible to mold the outer member using a simple mold structure.

[0028] Since the second retaining pieces that come into contact with the pair of stopper projections are provided on one opening side of each of the cylindrical parts, the effect of preventing the vibration isolator body from coming out of the cylindrical part by the second retaining pieces can be obtained on both sides in the axial direction. Also, for example, when a prying load is input between the inner shaft member and the outer member, by arranging the second retaining pieces according to the expected input direction of the prying load, it is also possible to prevent the vibration isolator body from coming out of the cylindrical part due to the input of the prying load.

[0029] A seventh aspect is a vibration-damping device described in any one of the first to sixth aspects, wherein the tubular portion is provided with a rotation limiting protrusion that protrudes toward the inner circumference on the circumferential side of the rubber arm portion, and the rotation limiting protrusion extends continuously outward in the axial direction of the tubular portion beyond the protruding tip of the rubber arm portion from the inner shaft member, and the rubber arm portion is engaged with the rotation limiting protrusion in the circumferential direction of the tubular portion, thereby forming a rotation limiting mechanism that limits the amount of relative rotation in the circumferential direction between the main rubber elastic body and the tubular portion.

[0030] With an anti-vibration device constructed according to this aspect, the abutment of the rotation limiting protrusion with the rubber arm portion can limit the relative rotation within the tubular portion of the anti-vibration device main body, and the anti-vibration device main body can be held in an appropriate circumferential orientation with respect to the tubular portion. Because the rotation limiting protrusion extends axially outward beyond the protruding tip of the rubber arm portion, a large abutment area between the rotation limiting protrusion and the rubber arm portion in the circumferential direction is ensured, and the abutment between the rotation limiting protrusion and the rubber arm portion is not released due to partial deformation of the rubber arm portion, effectively limiting the amount of relative rotation between the anti-vibration device main body and the tubular portion. In an eighth aspect, in an anti-vibration device in which an anti-vibration device main body having a structure in which a main rubber elastic body is fixed to the outer peripheral surface of an inner shaft member is inserted into a cylindrical portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastic body, the main rubber elastic body has a plurality of rubber arm portions which interconnect the inner shaft member and the cylindrical portion of the outer member, the plurality of rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, and first stop pieces which protrude inwardly at positions corresponding to the rubber arm portions in the circumferential direction are integrally formed at openings on both axial sides of the cylindrical portion, and the first stop pieces are abutted against the rubber arm portions to prevent the anti-vibration device main body from coming off the cylindrical portion. a first anti-removal portion is formed by engaging the rubber arm portion with the first anti-removal piece, and a plurality of the first anti-removal pieces are provided at a distance from each other in the circumferential direction of the tubular portion at at least one opening of the tubular portion, and each of the plurality of first anti-removal pieces is overlapped in the axial direction with respect to the rubber arm portion, and the tubular portion is provided with a rotation limiting protrusion protruding toward the inner circumference on the circumferential side of the rubber arm portion, and the rotation limiting protrusion extends continuously to the outside in the axial direction of the tubular portion beyond the tip of the rubber arm portion protruding from the inner shaft member, and the rubber arm portion is engaged with the rotation limiting protrusion in the circumferential direction of the tubular portion, thereby forming a rotation limiting mechanism which limits the amount of relative rotation in the circumferential direction between the main rubber elastic body and the tubular portion. The anti-vibration device constructed according to this embodiment is a non-adhesive type anti-vibration device in which the main rubber elastic body is assembled to the outer member in a non-adhesive state, so that the tensile stress generated in the main rubber elastic body when vibration is input is reduced, improving the durability of the main rubber elastic body. Also, by pre-compressing the main rubber elastic body, it is possible to further reduce the tensile stress and adjust the spring constant. The first retaining pieces of the outer member and the rubber arm portions of the main rubber elastic body come into contact with each other, thereby preventing the vibration damping device main body from coming out of the tubular portion of the outer member, and enabling the vibration damping device main body to be stably held in an assembled state to the outer member. Since a plurality of first retaining pieces are provided at intervals in the circumferential direction in at least one of the openings of the tubular portion, it becomes easier to obtain a large total contact area between the rubber arm portions and the first retaining pieces, and since the contact points between the first retaining pieces and the rubber arm portions are distributed in the circumferential direction, prevention of the rubber arm portions from coming out by contact with the first retaining pieces is more effectively realized. Furthermore, because the multiple first prevention pieces provided at at least one opening of the tubular portion are arranged spaced apart from one another in the circumferential direction, it is possible to visually check the state of the contact portion between the first prevention pieces and the rubber arm portion through the spaces between the multiple first prevention pieces, etc. This makes it easy to grasp the assembled state of the outer member and the main rubber elastic body, and allows the main rubber elastic body to be properly assembled to the outer member. Furthermore, with an anti-vibration device constructed according to this aspect, the abutment of the rotation limiting protrusion with the rubber arm portion can limit the relative rotation within the tubular portion of the anti-vibration device main body, and the anti-vibration device main body can be held in an appropriate circumferential orientation with respect to the tubular portion. Since the rotation limiting protrusion extends axially outward beyond the protruding tip of the rubber arm portion, a large abutment area between the rotation limiting protrusion and the rubber arm portion in the circumferential direction is ensured, and the abutment between the rotation limiting protrusion and the rubber arm portion is not released due to partial deformation of the rubber arm portion, effectively limiting the amount of relative rotation between the anti-vibration device main body and the tubular portion.

[0031] In the vibration-proof device constructed according to each of the above-mentioned aspects, for example, the radial inclination angle of both axial end faces of the rubber arm part gradually decreases from the radial inside to the radial outside, and the inclination angle is smallest at the outer peripheral end part of the rubber arm part where the retaining piece is overlapped, and the outer peripheral end part is an approximately flat overlapping surface that spreads in the circumferential direction with a predetermined width in the approximately axis-perpendicular direction. Also, it is desirable that the axial inner surface of the retaining piece overlapped with such overlapping surface also has a substantially flat surface shape that spreads in the circumferential direction with a predetermined width in the axis-perpendicular direction. However, the axial inner surface of the retaining piece may be an inclined surface that gradually slopes axially outward as it goes radially inward, taking into consideration the function as a guide surface of the rubber arm part to be assembled and the contact with the axial side surface of the rubber arm part, etc. In addition, in the vibration-proof device constructed according to each of the above-mentioned embodiments, a set of stopper projections is provided to project in the input direction of the main load (the largest load expected), and a set of rubber arms is provided to project toward both sides substantially perpendicular to the input direction of the main load. By intentionally providing the retaining pieces, which were considered important in non-bonded vibration-proof devices, only partially in the circumferential direction, it is possible to, for example, easily check the assembly state of the rubber arms, and improve the degree of freedom in tuning low spring characteristics by avoiding excessive constraint on the rubber arms. In particular, as shown in the seventh embodiment, by limiting the amount of deformation in the circumferential direction by regulating the position of the rubber arms in the circumferential direction, it is possible to limit the degree of deformation freedom of the outer periphery of the rubber arms when a load is input, and to more efficiently and reliably limit the slipping out of the rubber arms by the partial retaining pieces in the circumferential direction. Effect of the Invention

[0032] According to the present invention, it is possible to effectively prevent the vibration-damping device main body from coming loose from the outer member, which is a problem with non-bonded type vibration-damping devices, while easily achieving proper assembly of the vibration-damping device main body and outer member, which are assembled without bonding. [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a perspective view showing a torque rod according to a first embodiment of the present invention; [Diagram 2] Plan view of the torque rod shown in Figure 1 [Diagram 3] Bottom view of the torque rod shown in Figure 1 [Figure 4] IV-IV cross section of Figure 2 [Diagram 5] VV cross section of Figure 2 [Figure 6] An exploded perspective view of the torque rod shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0035] 1 to 5 show a torque rod 10 for an automobile as a first embodiment of a vibration-proof device structured according to the present invention. As shown in FIG. 6, the torque rod 10 has a structure in which a vibration-proof device main body 12 is assembled to a rod main body 14 as an outer member without bonding. In the following description, in principle, the up-down direction refers to the up-down direction in FIG. 4 which is the axial direction of an inner shaft member 16 and a cylindrical portion 34 described later, the left-right direction refers to the left-right direction in FIG. 2 which is the rod length direction of the rod main body 14, and the width direction refers to the up-down direction in FIG. 2 which is the width direction of the rod main body 14. In addition, in principle, the axial direction refers to the axial direction of the inner shaft member 16 and a cylindrical portion 34 described later, and the circumferential direction refers to the circumferential direction of the inner shaft member 16 and a cylindrical portion 34 described later.

[0036] The vibration isolation device main body 12 has a structure in which a main rubber elastic body 18 is fixed to an inner shaft member 16. The inner shaft member 16 is a high-rigidity member formed of metal, fiber-reinforced synthetic resin, or the like. The inner shaft member 16 is a columnar member that extends linearly in the vertical direction and has a bolt hole 20 that penetrates in the vertical direction. The inner shaft member 16 has a substantially isosceles trapezoidal shape when viewed in the vertical direction, and the width dimension (vertical dimension in FIG. 2) increases from one side to the other in the left-right direction (from left to right in FIG. 2). Therefore, the outer circumferential surface of the inner shaft member 16 has a wide surface 22 and a narrow surface 24 that have different width dimensions and extend substantially parallel to each other in the left-right direction, and a pair of inclined fixing surfaces 26, 26 that connect the wide surface 22 and the narrow surface 24 to each other.

[0037] The main rubber elastic body 18 has a pair of rubber arm portions 28, 28 that protrude from a pair of inclined fixing surfaces 26, 26 of the inner shaft member 16 toward the outer periphery. The rubber arm portions 28 are fixed to the pair of inclined fixing surfaces 26, 26, and are vulcanized and bonded, for example, when the main rubber elastic body 18 is molded. As shown in Figs. 2 and 3, the rubber arm portions 28 protrude from the inner shaft member 16 toward the outer periphery while inclining leftward, and the elastic main axis L extending in the protruding direction of the rubber arm portions 28 shown by the two-dot chain line in Fig. 2 is inclined leftward from the inner shaft member 16 toward the outer periphery. As shown in Fig. 4, the elastic main axis L of the rubber arm portions 28 is inclined upward from the inner shaft member 16 toward the outer periphery. The rubber arm portions 28 have a circumferential width dimension larger at the outer periphery end face, which is the protruding tip face, than at the inner periphery end face, which is the end face fixed to the inner shaft member 16. In addition, the rubber arm portion 28 has a smaller thickness in the vertical direction at the outer peripheral end face, which is the protruding tip face, than at the inner peripheral end face, which is the end face fixed to the inner shaft member 16. In this embodiment, the inclination angle of the axial end face of the rubber arm portion 28 with respect to the axis-perpendicular direction gradually decreases from the inner circumference to the outer circumference, with the inclination angle being smallest at the outer peripheral end. For example, the outer peripheral portion of the axial end face of the rubber arm portion 28 is provided with a flat surface that spreads in the axis-perpendicular direction and extends a predetermined length in the circumferential direction, and first and second retaining pieces 42, 44, which will be described later, are superimposed on this flat surface.

[0038] The main rubber elastic body 18 has a first stopper projection 30 projecting from the wide surface 22 of the inner shaft member 16 and a second stopper projection 32 projecting from the narrow surface 24 of the inner shaft member 16. The first stopper projection 30 and the second stopper projection 32 project in opposite directions in the left-right direction in which the wide surface 22 and the narrow surface 24 are aligned. The first stopper projection 30 and the second stopper projection 32 are provided between the rubber arm portions 28, 28 in the circumferential direction of the inner shaft member 16. The first stopper projection 30 and the second stopper projection 32 are continuous with the rubber arm portions 28, 28 in the circumferential direction of the inner shaft member 16 at their base ends, and are separated and independent from each other in the circumferential direction of the inner shaft member 16 at their tip ends. As shown in Fig. 2 and Fig. 3, the width dimension of the first stopper projection 30 is larger than the width dimension of the second stopper projection 32. As shown in Fig. 5, the first stopper projection 30 and the second stopper projection 32 have substantially the same vertical dimensions of the base end faces fixed to the inner shaft member 16, and substantially the same vertical dimensions of the protruding tip faces. The projection dimension of the first stopper projection 30 from the inner shaft member 16 is equal to or larger than the projection dimension of the second stopper projection 32 from the inner shaft member 16. The compression spring constant in the projection direction of the first stopper projection 30 is larger than the compression spring constant in the projection direction of the second stopper projection 32, and the compression spring characteristic of the first stopper projection 30 in the projection direction is harder than that of the second stopper projection 32.

[0039] The area of ​​the protruding tip surface of the rubber arm portion 28 is larger than both the area of ​​the protruding tip surface of the first stopper projection 30 and the area of ​​the protruding tip surface of the second stopper projection 32. The circumferential dimension of the protruding tip surface of the rubber arm portion 28 is larger than the circumferential dimension of the protruding tip surface of the first stopper projection 30, and is preferably at least twice the circumferential dimension of the protruding tip surface of the first stopper projection 30. The protruding tip surfaces of the first and second stopper projections 30 and 32 are preferably contact areas with the cylindrical portion 34 (described later) under the action state of the stopper load that is expected to be input, and are, for example, wider than the opposing surface having a shape corresponding to the inner peripheral surface of the cylindrical portion 34. The protruding tip surfaces of the first and second stopper projections 30 and 32 are, for example, the portions that contact the cylindrical portion 34 at the initial stage of contact when contacting the cylindrical portion 34.

[0040] The rod body 14 is a highly rigid member made of metal such as aluminum alloy or iron, or fiber-reinforced synthetic resin, and is preferably a molded product manufactured by die casting, injection molding, etc. The rod body 14 has a structure in which a pair of shaft portions 36, 36 extend rightward from a cylindrical portion 34.

[0041] The tubular portion 34 is substantially cylindrical and has a mounting hole 38 that penetrates in the vertical direction. The vibration isolator body 12, which includes the inner shaft member 16 and the main rubber elastic body 18, is inserted into the mounting hole 38 of the tubular portion 34 without being bonded. The inner peripheral surface of the tubular portion 34 has a smaller diameter than an imaginary cylindrical surface including the protruding tip surfaces of the rubber arm portions 28, 28 of the vibration isolator body 12. Therefore, when the vibration isolator body 12 is inserted into the mounting hole 38 of the tubular portion 34, the protruding tip surfaces of the rubber arm portions 28, 28 are pressed against the inner peripheral surface of the tubular portion 34, and the rubber arm portions 28, 28 are compressed in the protruding direction. In other words, the rubber arm portions 28, 28 are pre-compressed between the inner shaft member 16 and the tubular portion 34 when the vibration isolator body 12 is mounted on the tubular portion 34 of the rod body 14. The protruding tip surfaces of the rubber arm portions 28, 28 are pressed against the tubular portion 34, so that the inner shaft member 16 and the rod main body 14 having the tubular portion 34 are elastically connected by the rubber arm portions 28, 28 of the main rubber elastic body 18. The rubber arm portions 28, 28 are overlapped in a non-adhesive abutting state against the tubular portion 34 and are capable of relative displacement with respect to the tubular portion 34.

[0042] The vibration isolator body 12 is inserted into the tubular portion 34 with the rubber arm portions 28, 28 compressed by a cylindrical jig (not shown), for example. This reduces the frictional resistance acting between the rubber arm portions 28, 28 and the tubular portion 34 when the vibration isolator body 12 is inserted into the tubular portion 34, making it easier to insert the vibration isolator body 12 into the tubular portion 34. It is desirable that the protruding tip surface of the rubber arm portions 28, 28 in the state compressed by the jig is located on the inner periphery than the protruding tip surface of the first retaining piece 42 described later, which makes it easier to insert the vibration isolator body 12 into the tubular portion 34 and prevents damage to the rubber arm portions 28, 28 caused by the rubber arm portions 28, 28 climbing over the first retaining piece 42.

[0043] Furthermore, the protruding tip surfaces of the first and second stopper projections 30, 32 are spaced inwardly by a predetermined stopper clearance from the inner peripheral surface of the tubular portion 34. Therefore, the first and second stopper projections 30, 32 are not pre-compressed in the protruding direction when attached to the tubular portion 34 of the vibration isolator body 12.

[0044] The cylindrical portion 34 is provided with rotation limiting protrusions 40 that protrude toward the inner circumference on both circumferential sides of each rubber arm portion 28. The rotation limiting protrusions 40 extend continuously and linearly in the axial direction of the cylindrical portion 34 with a substantially constant rectangular cross section. The rotation limiting protrusions 40 are provided continuously over the entire axial length of the cylindrical portion 34, and extend to both axially outer sides beyond the protruding tip ends (outer peripheral ends) of the rubber arm portions 28 from the inner shaft member 16. The rotation limiting protrusions 40 overlap with the rubber arm portions 28 in the circumferential direction of the cylindrical portion 34. It is desirable that the rotation limiting protrusions 40 are in advance in the circumferential direction against the rubber arm portions 28 of the vibration isolator main body 12 attached to the cylindrical portion 34 in at least a part of the protruding direction. In this embodiment, the rotation limiting protrusions 40 are provided on both circumferential outer sides of each rubber arm portion 28, so that four rotation limiting protrusions are provided in the cylindrical portion 34 at positions spaced apart from each other in the circumferential direction.

[0045] A first retaining piece 42 is provided at a portion of the cylindrical portion 34 corresponding to the rubber arm portions 28, 28 in the circumferential direction. The first retaining piece 42 is a plate-like piece with the thickness direction being the up-down direction, and protrudes from the axial end of the cylindrical portion 34 toward the inner circumference. The first retaining piece 42 is provided at a position overlapping the rubber arm portion 28 in the up-down projection. The first retaining piece 42 may be provided at a position away from the rubber arm portion 28 toward the axial outside, but in this embodiment, the first retaining piece 42 is in advance in contact with the rubber arm portion 28, and the rubber arm portion 28 is pressed against the first retaining piece 42. The surface of the first retaining piece 42 that overlaps with the rubber arm portion 28 is a flat surface that extends in the axially perpendicular direction. The first retaining piece 42 is provided at the openings on both axial sides of the cylindrical portion 34. The first retaining piece is provided circumferentially between the rotation limiting protrusions 40, 40 provided on both circumferential sides of the rubber arm portion 28. The first retaining piece is formed integrally with the cylindrical portion .

[0046] Two first retaining pieces 42a, 42a are provided at the upper opening of the cylindrical portion 34 to be overlapped with the rubber arm portion 28. The first retaining pieces 42a, 42a are provided at a distance from each other in the circumferential direction and are overlapped with both circumferential end portions of the rubber arm portion 28 in the axial direction of the cylindrical portion 34. The first retaining pieces 42a, 42a are provided at a distance from each other in the circumferential direction with respect to a pair of rotation limiting protrusions 40, 40. The circumferential distance between the first retaining pieces 42a, 42a is larger than the circumferential distance between the first retaining pieces 42a and the rotation limiting protrusion 40 adjacent to each other in the circumferential direction. The multiple first retaining pieces 42a are formed to have approximately the same shape and size in this embodiment, but may have different shapes and sizes. The first anti-removal pieces 42a provided at the upper opening of the tubular portion 34 are provided in pairs for each rubber arm portion 28, so that there are four of them for the entire tubular portion 34, each of which is provided at positions spaced apart from each other in the circumferential direction.

[0047] Since a plurality of first retaining pieces 42a are provided at a distance from one another in the circumferential direction at the upper opening of the tubular portion 34, the assembled state of the rubber arm portion 28 to the tubular portion 34 can be visually confirmed from above, for example, through the circumferential space between the first retaining pieces 42a, 42a superimposed on one rubber arm portion 28. That is, when the vibration isolator main body 12 is inserted and assembled into the tubular portion 34, the compressed rubber arm portions 28, 28 elastically restore their shape on the inner circumference of the tubular portion 34 and are pressed against the tubular portion 34, so that the relative positions and contact state of the rubber arm portions 28, 28 to the tubular portion 34 may vary. Therefore, in the torque rod 10, the first anti-removal pieces 42a, 42a are arranged partially in the circumferential direction without covering the entire upper surface of the protruding tip of the rubber arm portion 28, so that even after insertion of the vibration-damping device main body 12 into the tubular portion 34, it is possible to easily confirm whether the rubber arm portions 28, 28 are properly abutting against the inner surface of the tubular portion 34, and whether the rubber arm portions 28, 28 are properly positioned in the axial and circumferential directions relative to the tubular portion 34.

[0048] Since the first retaining pieces 42a are spaced apart from the rotation limiting protrusion 40 in the circumferential direction, the assembled state of the rubber arm portion 28 and the tubular portion 34 at the circumferential end of the rubber arm portion 28 can be confirmed through the circumferential gap between the first retaining pieces 42a and the rotation limiting protrusion 40. Also, since the first retaining pieces 42a, 42a are spaced apart from each other in the circumferential direction and overlapped with both circumferential end portions of the rubber arm portion 28, the assembled state of the rubber arm portion 28 and the tubular portion 34 at the circumferential center portion of the rubber arm portion 28 can be confirmed through the circumferential gap between the first retaining pieces 42a, 42a. As a result, in this embodiment, the assembled state of the rubber arm portion 28 and the tubular portion 34 can be confirmed at both circumferential end portions and the center portion of the assembled portion where assembly defects are relatively likely to be a problem, and the assembled state of the rubber arm portion 28 and the tubular portion 34 can be more accurately grasped.

[0049] The circumferential ends of the rubber arm portion 28 are prone to deformation, making the assembled state unstable. In this embodiment, the frictional resistance caused by the contact between the circumferential end faces of the rubber arm portion 28 and the rotation limiting protrusions 40 can also lead to an improper assembled state. In addition, when the rubber arm portion 28 is properly assembled to the tubular portion 34 at both circumferential ends, a poor assembled state is likely to be a problem in the circumferential center portion of the rubber arm portion 28, which is a long distance from both circumferential ends of the rubber arm portion 28. In this embodiment, the assembled state can be confirmed at both circumferential ends and the circumferential center portion of the rubber arm portion 28, so that the assembled state of the rubber arm portion 28 and the tubular portion 34 can be reliably grasped.

[0050] The direction of insertion of the vibration isolator body 12 into the tubular portion 34 is not particularly limited, but for example, when the vibration isolator body 12 is inserted into the tubular portion 34 from below, since a defective assembly is likely to occur at the upper end of the rubber arm portion 28, it is effective to check the assembly state through the gap between the upper first retaining pieces 42a, 42a. Also, if a defective assembly state is found by visual inspection or the like, it is possible to correct the position or contact state of the rubber arm portion 28 relative to the tubular portion 34 by applying an external force to the protruding tip of the rubber arm portion 28 through the circumferential gap between the first retaining pieces 42a, 42a.

[0051] A first retaining piece 42b is provided at the opening on the lower side of the cylindrical portion 34, which is overlapped with the center portion of the rubber arm portion 28 in the circumferential direction. The first retaining piece 42b is located between the first retaining pieces 42a, 42a in the circumferential direction in the axial projection of the cylindrical portion 34. The first retaining pieces 42a, 42a and the first retaining piece 42b are provided at different positions in the circumferential direction of the cylindrical portion 34, and are arranged at positions where they do not overlap with each other in the axial projection of the cylindrical portion 34. In this embodiment, the first retaining pieces 42a, 42a abut on the upper surface of the rubber arm portion 28, and the first retaining piece 42b abuts on the lower surface of the rubber arm portion 28. The sum of the overlapping areas of the first retaining pieces 42a, 42a, 42a, 42a and the rubber arm portion 28 is larger than the sum of the overlapping areas of the first retaining pieces 42b, 42b and the rubber arm portion 28. In this embodiment, the first retaining piece 42a and the first retaining piece 42b have approximately the same shape and size. However, the shapes and sizes of the first retaining piece 42a and the first retaining piece 42b can also be made different from each other based on, for example, differences in the expected input load.

[0052] The first retaining piece 42b does not cover the entire circumferential length of the protruding tip of the rubber arm portion 28, but is partially overlapped in the circumferential direction with the protruding tip of the rubber arm portion 28. This allows, for example, the assembly state of the rubber arm portion 28 to the tubular portion 34 to be visually confirmed from below on both circumferential sides of the first retaining piece 42b that is overlapped with one rubber arm portion 28. Note that the position and contact state of the rubber arm portion 28 to the tubular portion 34 can also be corrected by applying an external force to the protruding tip of the rubber arm portion 28 through the gaps on both circumferential sides of the first retaining piece 42b.

[0053] A second retaining piece 44 is provided at a portion of the cylindrical portion 34 corresponding to the first and second stopper projections 30, 32 in the circumferential direction. The second retaining piece 44 is a plate-like piece with the thickness direction being the up-down direction, and protrudes from the cylindrical portion 34 toward the inner circumference at the axial end of the cylindrical portion 34. The second retaining piece 44 is provided at a position where it overlaps with the protruding tip portions of the first and second stopper projections 30, 32 in the up-down projection. The second retaining piece 44 may abut against the first and second stopper projections 30, 32, but in this embodiment, it is provided away from the first and second stopper projections 30, 32 to the outside in the axial direction of the cylindrical portion 34. The second retaining piece 44 is disposed on the opposite side of the first retaining piece 42 in the circumferential direction of the cylindrical portion 34 with respect to the rotation limiting projection 40. In this embodiment, the second retaining piece 44 is spaced apart from the rotation limiting projection 40 in the circumferential direction. The second retaining piece 44 is provided at each opening on both axial sides of the cylindrical portion 34. The second retaining piece 44 is integrally formed with the cylindrical portion 34. The axial end faces of the stopper projections 30, 32 that are overlapped with the second retaining piece 44 have an inclination angle with respect to the axis perpendicular direction that gradually decreases from the inner shaft member 16 side toward the cylindrical portion 34 side, and the inclination angle is minimum at the outer peripheral end portion that is overlapped with the second retaining piece 44.

[0054] The second retaining piece 44a overlapping with the first stopper projection 30 and the second retaining piece 44b overlapping with the second stopper projection 32 are provided at one opening in the axial direction of the cylindrical portion 34. That is, in this embodiment, the second retaining piece 44a is provided at the upper opening of the cylindrical portion 34, and the second retaining piece 44b is provided at the lower opening of the cylindrical portion 34. In this embodiment, the second retaining piece 44a and the second retaining piece 44b have substantially the same shape and size. However, for example, the circumferential dimension of the second retaining piece 44a overlapping with the first stopper projection 30 having a wide width in the circumferential direction may be larger than the circumferential dimension of the second retaining piece 44b overlapping with the second stopper projection 32 having a narrow width in the circumferential direction. The circumferential dimension of the second retaining piece 44a is desirably larger than the circumferential dimension of the protruding tip portion of the first stopper projection 30 that is to be overlapped with the second retaining piece 44a. Similarly, the circumferential dimension of the second retaining piece 44b is desirably larger than the circumferential dimension of the protruding tip portion of the second stopper projection 32 that is to be overlapped with the second retaining piece 44b.

[0055] The pair of shaft-like portions 36, 36 extending from the cylindrical portion 34 are rod-shaped or longitudinal plate-shaped, and in this embodiment, they are longitudinal plate-shaped members extending substantially parallel to each other in the plate thickness direction. The extending direction of the shaft-like portions 36, 36 from the cylindrical portion 34 is substantially the same as the protruding direction of the first stopper projection 30 from the inner shaft member 16. The shaft-like portion 36 has one end in the longitudinal direction integrally connected to the cylindrical portion 34, and has an attachment portion 46 at the other end in the longitudinal direction. The attachment portion 46 is substantially annular plate-shaped, and has an attachment hole 48 penetrating in the opposing direction of the shaft-like portions 36, 36, which is the plate thickness direction. A bush (not shown) is disposed between the attachment portions 46, 46 of the pair of shaft-like portions 36, 36, and an inner cylindrical member of the bush is fixed to the attachment portions 46, 46 with a bolt.

[0056] Therefore, a first bush constituted by the vibration isolation device main body 12 and the cylindrical portion 34 is provided at one longitudinal end of the shaft-shaped portions 36, 36, and a second bush (not shown) attached to the mounting portions 46, 46 is provided at the other longitudinal end of the shaft-shaped portions 36, 36. Then, for example, the inner shaft member 16 of the first bush is attached to the vehicle body, and the outer cylindrical member of the second bush attached to the mounting portions 46, 46 is attached to the power unit, so that the power unit and the vehicle body are connected in a vibration-proof manner by the torque rod 10. In this manner, the power unit and the vehicle body are connected in a vibration-proof manner by the torque rod 10, so that the reaction force (torque reaction force) against the force generated by the power unit is received by the torque rod 10, and the displacement of the power unit is regulated. Also, since a bush is provided at each end of the torque rod 10, the vibration transmitted from the power unit to the vehicle body is reduced, and a good ride comfort is realized.

[0057] The main rubber elastic body 18 of the vibration isolation device main body 12 is inserted into the tubular portion 34 of the rod main body 14 without bonding and assembled in a press-fit state. Therefore, the rubber arm portions 28, 28 of the main rubber elastic body 18, which elastically connect the inner shaft member 16 and the tubular portion 34 of the rod main body 14, are less likely to experience tensile stress when vibration is input in a direction that generates tensile stress, by moving away from the tubular portion 34. As a result, damage or breakage of the rubber arm portions 28, 28 due to the generation of tensile stress is prevented, and excellent durability is achieved for the rubber arm portions 28, 28.

[0058] Furthermore, the amount of relative displacement between the inner shaft member 16 and the tubular portion 34 is limited by a first stopper mechanism in which the wide surface 22 of the inner shaft member 16 and the inner peripheral surface of the tubular portion 34 abut against each other via the first stopper projection 30, and a second stopper mechanism in which the narrow surface 24 of the inner shaft member 16 and the inner peripheral surface of the tubular portion 34 abut against each other via the second stopper projection 32. This makes it difficult for the elastic deformation of the rubber arm portions 28, 28 to become excessively large, and prevents a decrease in durability due to excessive deformation of the rubber arm portions 28, 28.

[0059] In this embodiment, the elastic main axis L (two-dot chain line in FIG. 2) of the rubber arm parts 28, 28 extending in the connecting direction between the inner shaft member 16 and the cylindrical part 34 is inclined from the inner shaft member 16 side toward the outer periphery, which is the cylindrical part 34 side, in the protruding direction of the second stopper projection 32 (leftward in FIG. 2). As a result, when the inner shaft member 16 is displaced toward the second stopper projection 32 side with respect to the cylindrical part 34, the relative displacement amount between the inner shaft member 16 and the cylindrical part 34 is limited by the compression spring component of the rubber arm parts 28, 28. On the other hand, when the inner shaft member 16 is displaced toward the first stopper projection 30 side with respect to the cylindrical part 34, the compression spring component of the rubber arm parts 28, 28 is small, and the relative displacement amount between the inner shaft member 16 and the cylindrical part 34 is not easily limited by the spring of the rubber arm parts 28, 28. Therefore, the first stopper projection 30 is made larger in width than the second stopper projection 32, and the compression spring constant in the protruding direction is made larger than the second stopper projection 32. Therefore, the first stopper projection 30 exerts an excellent stopper effect in the direction in which the relative displacement between the inner shaft member 16 and the cylindrical portion 34 is likely to increase due to the small spring constant of the rubber arm portions 28. The fixing surfaces of the rubber arm portions 28 on the inner shaft member 16 are inclined fixing surfaces 26 connecting the wide surface 22 and the narrow surface 24, so that when the inner shaft member 16 is displaced toward the second stopper projection 32 relative to the cylindrical portion 34, the rubber arm portions 28 can obtain a hard spring characteristic due to the compression spring component.

[0060] Incidentally, the vibration-damping device main body 12, which is assembled to the tubular portion 34 of the rod main body 14 without adhesive, may come loose from the tubular portion 34, but a locking portion is provided to prevent the vibration-damping device main body 12 from coming loose from the tubular portion 34 in this manner.

[0061] That is, the first retaining piece 42 comes into contact with and engages the protruding tip of the rubber arm portion 28, thereby forming a first retaining portion that limits the amount of vertical displacement of the vibration isolator body 12 relative to the tubular portion 34, thereby preventing the vibration isolator body 12 from coming off from the tubular portion 34. The first retaining portion can prevent the vibration isolator body 12, which is equipped with the main rubber elastic body 18 including the rubber arm portions 28, 28, from coming off from the tubular portion 34 of the rod body 14 to which it is assembled without adhesive.

[0062] The first retaining pieces 42 are provided at the openings on both axial sides of the tubular portion 34, and thus prevent the vibration isolator body 12 from falling out of the tubular portion 34 on both axial sides of the tubular portion 34. That is, the abutment of the four first retaining pieces 42a, 42a, 42a, 42a with the rubber arm portion 28 forms an upper first retaining portion that prevents the vibration isolator body 12 from falling out of the tubular portion 34 to the upward side, and the abutment of the two first retaining pieces 42b, 42b with the rubber arm portion 28 forms a lower first retaining portion that prevents the vibration isolator body 12 from falling out of the tubular portion 34 to the downward side.

[0063] In particular, at the upper opening of the tubular portion 34 where the slipping out of the vibration isolator body 12 is likely to be a problem, two first retaining pieces 42a, 42a are provided for each rubber arm portion 28. The sum of the contact areas of the first retaining pieces 42a, 42a, 42a, 42a at the upper first retaining portion and the rubber arm portion 28 is made larger than the sum of the contact areas of the first retaining pieces 42b, 42b at the lower first retaining portion and the rubber arm portion 28. Therefore, the slipping out of the vibration isolator body 12 upward from the tubular portion 34 is more effectively prevented by the displacement of each rubber arm portion 28 being restricted by the two first retaining pieces 42a, 42a. Moreover, the two first retaining pieces 42a, 42a are overlapped with the rubber arm portion 28 at positions spaced apart from each other in the circumferential direction. As a result, the rubber arm portion 28 abuts against and is locked by the first retaining pieces 42a, 42a at two locations spaced apart from each other in the circumferential direction, and displacement of the rubber arm portion 28 relative to the tubular portion 34 is effectively restricted.

[0064] In this embodiment, the elastic main axis L (two-dot chain line in FIG. 4) of the rubber arm portions 28, 28 extending in the connecting direction between the inner shaft member 16 and the cylindrical portion 34 is inclined upward from the inner shaft member 16 side toward the outer periphery side, which is the cylindrical portion 34 side. As a result, when the rubber arm portion 28 is compressed between the inner shaft member 16 and the cylindrical portion 34, an upward component force acts on the outer periphery end of the rubber arm portion 28, so that the rubber arm portion 28 is easily displaced upward from the cylindrical portion 34. Here, the first retaining piece 42a, which has a large contact area with the rubber arm portion 28 and restricts the displacement of the rubber arm portion 28 at two points in the circumferential direction, is provided at the upper opening of the cylindrical portion 34, so that the vibration isolator main body 12 is effectively prevented from coming off from the cylindrical portion 34 at the upper opening of the cylindrical portion 34, where coming off of the vibration isolator main body 12 is likely to be a problem.

[0065] On the other hand, at the lower opening of the tubular portion 34, only one first retaining piece 42b is provided for each rubber arm portion 28, and the overlapping area of ​​the first retaining piece 42b and the rubber arm portion 28 is made smaller than the sum of the overlapping areas of the first retaining pieces 42a, 42a and the rubber arm portion 28. As a result, at the lower opening of the tubular portion 34, where the vibration isolator body 12 is less likely to come off, the number of first retaining pieces 42b is reduced, thereby achieving a reduction in weight and a simplified structure while still achieving an effective retaining effect.

[0066] The first retaining piece 42b provided at the lower opening of the tubular portion 34 is overlapped with the center portion of the rubber arm portion 28 in the circumferential direction. This allows the rubber arm portion 28 to be prevented from falling out downward in a well-balanced manner by one first retaining piece 42b. In addition, the first retaining piece 42a provided at the upper opening of the tubular portion 34 and the first retaining piece 42b provided at the lower opening of the tubular portion 34 are arranged without overlapping each other when projected in the axial direction of the tubular portion 34. Therefore, for example, when the tubular portion 34 including the upper first retaining piece 42a and the lower first retaining piece 42b is formed by molding, even if a simple mold structure that is divided in the axial direction of the tubular portion 34 is adopted, it is possible to prevent the first retaining piece 42 from being undercut.

[0067] In this embodiment, when the vibration-damping device main body 12 is attached to the rod main body 14, the outer peripheral end of the rubber arm portion 28 is already abutted against the first anti-removal piece 42, and therefore misalignment of the vibration-damping device main body 12 relative to the tubular portion 34 is also suppressed by the rubber arm portions 28, 28 abutting against the first anti-removal piece 42.

[0068] In addition, the vibration-damping device main body 12, which is assembled to the tubular portion 34 of the rod main body 14 without adhesive, is also prevented from coming off from the tubular portion 34 by the second anti-pullout portion formed by the abutment between the first and second stopper protrusions 30, 32 and the second anti-pullout piece 44 provided on the tubular portion 34.

[0069] That is, the second retaining piece 44a provided on the upper side of the protruding tip of the first stopper projection 30 comes into axial contact with and engages with the first stopper projection 30, thereby forming an upper second retaining portion that limits the amount of upward relative displacement of the vibration isolator body 12 with respect to the tubular portion 34. The second retaining piece 44b provided on the lower side of the protruding tip of the second stopper projection 32 comes into axial contact with and engages with the second stopper projection 32, thereby forming a lower second retaining portion that limits the amount of downward relative displacement of the vibration isolator body 12 with respect to the tubular portion 34. In this way, the second retaining portion formed by the abutment and engagement of the first and second stopper projections 30, 32 with the second retaining piece 44 also prevents the vibration isolator body 12 from coming out of the tubular portion 34.

[0070] Since the second retaining piece 44a is provided on the upper side of the first stopper projection 30 and the second retaining piece 44b is provided on the lower side of the second stopper projection 32, the second retaining pieces prevent the vibration isolation device main body 12 from coming off from the tubular portion 34 on both axial sides of the tubular portion 34. Furthermore, for example, when a prying load is input to the tubular portion 34 such that the first stopper projection 30 is displaced upward and the second stopper projection 32 is displaced downward, the amount of prying displacement of the inner shaft member 16 and the tubular portion 34 can also be limited by the abutment of the first and second stopper projections 30, 32 with the second retaining pieces 44a, 44b.

[0071] The width dimension of the second retaining piece 44a in the circumferential direction of the tubular portion 34 is made larger than the width dimension of the first stopper projection 30, and the protruding tip of the first stopper projection 30 overlaps with the second retaining piece 44a over the entire width direction. Also, the width dimension of the second retaining piece 44b in the circumferential direction of the tubular portion 34 is made larger than the width dimension of the second stopper projection 32, and the protruding tip of the second stopper projection 32 overlaps with the second retaining piece 44b over the entire width direction. As a result, the second retaining portion using the first and second stopper projections 30, 32, which have a smaller circumferential width than the rubber arm portion 28, can effectively obtain a retaining effect.

[0072] Furthermore, the vibration isolator body 12 and the tubular portion 34, which are assembled without adhesive, may rotate relative to each other in the circumferential direction, but in this embodiment, the side surface of the rubber arm portion 28 abuts and engages with a rotation limiting protrusion 40 provided on the tubular portion 34 in the circumferential direction, thereby forming a rotation limiting mechanism that limits the amount of relative rotation in the circumferential direction between the vibration isolator body 12 and the tubular portion 34. In this embodiment, the rubber arm portion 28 and the rotation limiting protrusion 40 abut in advance in the circumferential direction, and the vibration isolator body 12 and the tubular portion 34 are positioned relative to each other in the circumferential direction. In this embodiment, the amount of rotational displacement of the vibration isolator body 12 with respect to the tubular portion 34 is limited on both sides in the circumferential direction by the multiple rotation limiting protrusions 40. The rotation limiting protrusion 40 is provided continuously outward in the axial direction from the protruding tip of the rubber arm portion 28, and the protruding tip of the rubber arm portion 28 abuts against the rotation limiting protrusion 40 over almost the entire length in the axial direction, so that the abutment and engagement between the rubber arm portion 28 and the rotation limiting protrusion 40 is unlikely to be released by deformation of the rubber arm portion 28.

[0073] Although the embodiment of the present invention has been described in detail above, the present invention is not limited by the specific description. For example, the number, arrangement, shape, size, etc. of the first retaining pieces 42 are not limited. In addition, the upper first retaining pieces 42a and the lower first retaining pieces 42b may have different shapes and sizes, and may be provided at positions where they overlap each other when projected in the axial direction of the cylindrical portion 34.

[0074] In the above embodiment, the structure in which the upper first retaining piece 42a and the lower first retaining piece 42b are both formed integrally with the tubular portion 34 has been exemplified, but, for example, at least one of the upper first retaining piece 42a and the lower first retaining piece 42b may be provided in a component separate from the tubular portion 34. Specifically, for example, a ring-shaped retaining member that is superimposed and fixed to the lower surface of the tubular portion 34 may be formed separately from the tubular portion 34, and the first retaining piece 42b may be formed integrally with the retaining member, so that the first retaining piece 42b can be provided so as to protrude toward the inner circumference with respect to the tubular portion 34 by fixing the retaining member to the tubular portion 34. Note that the second retaining piece 44 and the rotation limiting protrusion 40 may be formed separately from the tubular portion 34 and fixedly provided to the tubular portion 34.

[0075] The first retaining piece 42 is desirably provided at the axial end of the tubular portion 34 from the viewpoint of ensuring the rubber volume of the rubber arm portion 28, but may be provided, for example, midway in the axial direction of the tubular portion 34. Similarly, the second retaining piece 44 may be provided midway in the axial direction of the tubular portion 34. In short, providing the first retaining piece 42 or the second retaining piece 44 at the opening of the tubular portion 34 does not only mean providing it at the axial end of the tubular portion 34, but also includes providing it midway in the axial direction of the tubular portion 34 as long as it is located axially outward of the rubber arm portion 28.

[0076] Checking the assembled state of the rubber arm portion 28 and the tubular portion 34 through the circumferential space between the first anti-removal pieces 42a, 42a is not limited to visual check, and for example, the relative positional relationship between the protruding tip of the rubber arm portion 28 and the tubular portion 34 can also be automatically checked using laser or radio wave surveying equipment.

[0077] The mating surface between the first anti-slip piece 42 and the rubber arm portion 28 may be approximately perpendicular to the axial direction as in the above embodiment, or may be inclined axially outward toward the inner circumference to facilitate assembly to the tubular portion 34 of the vibration-damping device main body 12, or may be inclined axially inward toward the inner circumference to more effectively prevent the vibration-damping device main body 12 from coming off the tubular portion 34.

[0078] The second retaining piece 44 is not essential and can be omitted. Also, the second retaining pieces 44a, 44b can be provided on both axial sides of one stopper projection 30 (32), and the second retaining parts on both axial sides can be configured by abutting one stopper projection 30 (32) with the second retaining pieces 44a, 44b.

[0079] The shape of the inner shaft member 16 is not limited, and may be, for example, a cylinder including an elliptical cylinder, a rectangular cylinder, a polygonal prism other than a square, an irregular cylinder, etc. The inner shaft member 16 may also be a solid rod, in which case, for example, a mounting structure to a vehicle or the like, such as a screw, may be provided at the axial end.

[0080] The elastic main axis L of the rubber arm portion 28 does not necessarily have to be inclined in the vertical or longitudinal direction. Three or more rubber arm portions 28 may be provided. In addition, the first retaining piece 42 does not necessarily have to be provided in the portion corresponding to all of the rubber arm portions 28, and the first retaining piece 42 may not be provided in the portion corresponding to one or some but not all of the multiple rubber arm portions.

[0081] The rod main body is not particularly limited in the specific structure of the shaft portion 36, etc., as long as it has the cylindrical portion 34. Specifically, for example, it may have one shaft portion extending from the outer circumferential surface of the cylindrical portion 34, and a cylindrical bush press-fit portion separate from the cylindrical portion 34 may be provided at the end of the shaft portion opposite the cylindrical portion 34.

[0082] The present invention can be applied to vibration-isolating devices other than torque rods. Specifically, the present invention can be applied to cylindrical vibration-isolating devices such as suspension links and suspension bushes. The present invention can also be applied to fluid-filled vibration-isolating devices that exert vibration-isolating effects by the flow action of a liquid filled inside. The present invention essentially includes each of the inventions described in (i) to (vii) below, and the configurations and effects thereof will be described below. The present invention relates to (i) an anti-vibration device in which an anti-vibration device main body having a structure in which a main rubber elastic body is fixed to the outer peripheral surface of an inner shaft member is inserted into a cylindrical portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastic body, the main rubber elastic body has a plurality of rubber arm portions which interconnect the inner shaft member and the cylindrical portion of the outer member, the plurality of rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, first stop pieces which protrude toward the inner circumference are formed integrally with openings on both axial sides of the cylindrical portion at positions corresponding to the rubber arm portions in the circumferential direction, and a first stop portion which prevents the anti-vibration device main body from coming off the cylindrical portion is formed by abutting the first stop pieces with the rubber arm portions, and a plurality of the first stop pieces are provided at at least one opening of the cylindrical portion so as to be spaced apart from each other in the circumferential direction of the cylindrical portion, and the plurality of first stop pieces are each overlapped in the axial direction with the rubber arm portions; (ii) The vibration-proof device according to (i), in which the first retaining piece on one axial side of the tubular portion and the first retaining piece on the other axial side are formed at different positions in the circumferential direction of the tubular portion and are arranged so as not to overlap with each other when projected in the axial direction. (iii) The vibration-proof device according to (ii), in which the first retaining piece on one axial direction side is provided at a position corresponding to a central portion of the rubber arm portion in the circumferential direction of the tubular portion, and the first retaining piece on the other axial direction side is provided on both sides of the first retaining piece on one axial direction side in the circumferential direction of the tubular portion, and the sum of the overlapping areas of the first retaining piece on the other axial direction side and the rubber arm portion is larger than the sum of the overlapping areas of the first retaining piece on one axial direction side and the rubber arm portion. (iv) The vibration-proof device according to any one of (i) to (iii), wherein the elastic main axis of the rubber arm portion extending in the connecting direction between the inner shaft member and the tubular portion is inclined in the axial direction from the inner shaft member side toward the tubular portion side. (v) An anti-vibration device as set forth in any one of (i) to (iv), in which the main rubber elastic body is provided with a stopper projection projecting from the inner shaft member towards the tubular portion between the multiple rubber arm portions in the circumferential direction, and a second retaining piece projecting inwardly at a position corresponding to the stopper projection in the circumferential direction is integrally formed in at least one of the openings of the tubular portion, and a second retaining piece that prevents the anti-vibration device main body from coming off the tubular portion is formed by abutting the second retaining piece with the stopper projection; (vi) A vibration-proof device as described in (v), in which a pair of the stopper projections project outwardly from both sides in the radial direction of the inner shaft member, the second retaining piece provided at a position corresponding to one of the stopper projections is formed on the opening side of one axial direction of the cylindrical portion relative to the one stopper projection, and the second retaining piece provided at a position corresponding to the other stopper projection is formed on the opening side of the other axial direction of the cylindrical portion relative to the other stopper projection. (vii) An anti-vibration device according to any one of (i) to (vi), wherein the tubular portion is provided with a rotation limiting protrusion that protrudes inwardly on a circumferential side of the rubber arm portion, the rotation limiting protrusion extending continuously outward in the axial direction of the tubular portion beyond a protruding tip of the rubber arm portion from the inner shaft member, and the rubber arm portion is engaged with the rotation limiting protrusion in the circumferential direction of the tubular portion to form a rotation limiting mechanism that limits the amount of relative rotation in the circumferential direction between the main rubber elastic body and the tubular portion; This includes inventions relating to. In the invention described in (i) above, since the main rubber elastic body is a non-bonded type vibration-proof device in which the main rubber elastic body is assembled to the outer member in a non-bonded state, the tensile stress generated in the main rubber elastic body when vibration is input is reduced, improving the durability of the main rubber elastic body. In addition, the main rubber elastic body is pre-compressed, which makes it possible to further reduce the tensile stress and adjust the spring constant. The first retaining piece of the outer member and the rubber arm portion of the main rubber elastic body abut against each other, preventing the vibration-proof device main body from coming off the tubular portion of the outer member, and the vibration-proof device main body can be stably held in a state assembled to the outer member. Since a plurality of first retaining pieces are provided at a distance from each other in the circumferential direction in at least one of the openings of the tubular portion, it is easy to obtain a large total contact area between the rubber arm portion and the first retaining piece, and since the contact points between the first retaining pieces and the rubber arm portion are distributed in the circumferential direction, prevention of the rubber arm portion from coming off due to abutment against the first retaining piece is more effectively realized. Furthermore, because the multiple first prevention pieces provided at at least one opening of the tubular portion are arranged spaced apart from one another in the circumferential direction, it is possible to visually check the state of the contact portion between the first prevention pieces and the rubber arm portion through the spaces between the multiple first prevention pieces, etc. This makes it easy to grasp the assembled state of the outer member and the main rubber elastic body, and allows the main rubber elastic body to be properly assembled to the outer member. In the invention described in (ii) above, a simple mold structure divided in the axial direction of the tubular part can easily mold an outer member in which first retaining pieces protruding toward the inner circumference of the tubular part are provided at the open ends on both axial sides of the tubular part. Preferably, the retaining parts on both axial sides have a shorter circumferential length than the outer periphery of the rubber arm part, and two or more circumferential ends of the retaining parts are provided circumferentially spaced apart on the axial side of the rubber arm part. This makes it easier and more accurate to check that the rubber arm part is correctly assembled by fitting it axially inwardly to the retaining parts. In the invention described in (iii) above, the first retaining piece provided on one axial side is overlapped with the center part of the rubber arm part in the circumferential direction, so that the contact reaction force acting on the rubber arm part by the contact with the first retaining piece is applied to the rubber arm part in a balanced manner, and the rubber arm part can be efficiently prevented from coming off to one axial side by the small number of first retaining pieces. In addition, the multiple first retaining pieces provided on the other axial side are overlapped with the rubber arm part at positions spaced apart from each other in the circumferential direction, so that the vibration isolator main body is effectively prevented from coming off to the other axial side from the tubular part. Moreover, the overlapping area of ​​the multiple first retaining pieces provided on the other axial side with the rubber arm part is larger than the overlapping area of ​​the first retaining piece provided on one axial side with the rubber arm part, so that the vibration isolator main body is more effectively prevented from coming off to the other axial side. Therefore, when the resistance against coming off required on both axial sides is different, such as when the axial force acting on the vibration isolator main body is different between one axial direction and the other axial direction, it is possible to obtain effective resistance against coming off on both axial sides. In the invention described in (iv) above, the vibration isolator body can be easily assembled to the outer member by considering the insertion direction of the vibration isolator body into the cylindrical portion, for example, by inserting the vibration isolator body into the cylindrical portion from the side with the smaller outer dimension of the rubber arm portion. Also, when an axial force is input, which expands the outer dimension of the inclined rubber arm portion, the frictional resistance acting between the rubber arm portion and the cylindrical portion increases due to the deformation of the rubber arm portion, and a large resistance force against the vibration isolator body coming out of the cylindrical portion can be obtained. Therefore, for example, when the maximum value of the axial load input between the inner shaft member and the outer member is different on both sides in the axial direction, the axial direction of the vibration isolator body can be set in consideration of the magnitude of the input load, thereby advantageously preventing the vibration isolator body from coming out of the cylindrical portion. In the invention described in (v) above, the abutment between the stopper projection and the tubular portion limits the amount of relative displacement between the inner shaft member and the outer member in the direction perpendicular to the axis, thereby preventing excessive elastic deformation of the main rubber elastic body and improving the durability of the main rubber elastic body. Also, the anti-vibration device main body is prevented from coming off the tubular portion not only by the first prevention portion formed by the abutment between the first prevention piece and the rubber arm portion, but also by the second prevention portion formed by the abutment between the second prevention piece and the stopper projection, so that the appropriate assembly state of the anti-vibration device main body and the outer member is more effectively maintained. In the invention described in (vi) above, since the second retaining pieces are provided on one side of the stopper projection in the axial direction, when the outer member having the second retaining pieces is molded, undercut in the axial direction by the second retaining pieces is avoided, and the outer member can be molded with a simple mold structure. Since the second retaining pieces that come into contact with a pair of stopper projections are provided on one opening side of each of the cylindrical parts, the effect of preventing the vibration-isolating device main body from coming out of the cylindrical part by the second retaining parts can be obtained on both sides in the axial direction. In addition, for example, when a prying load is input between the inner shaft member and the outer member, the second retaining pieces can be arranged according to the expected input direction of the prying load to prevent the vibration-isolating device main body from coming out of the cylindrical part due to the input of the prying load. In the invention described in (vii) above, the abutment of the rotation limiting protrusion with the rubber arm portion makes it possible to limit the relative rotation within the tubular portion of the vibration isolator body, and the vibration isolator body can be held in an appropriate circumferential orientation with respect to the tubular portion. Since the rotation limiting protrusion extends axially outward beyond the protruding tip of the rubber arm portion, a large abutment area between the rotation limiting protrusion and the rubber arm portion in the circumferential direction is ensured, and the abutment between the rotation limiting protrusion and the rubber arm portion is not released due to partial deformation of the rubber arm portion, so that the amount of relative rotation between the vibration isolator body and the tubular portion is effectively limited. [Explanation of symbols]

[0083] 10 Torque rod (vibration isolation device) 12 Anti-vibration device body 14 Rod body (outer member) 16 Inner shaft member 18 Main rubber elastic body 20 Bolt holes 22 Wide surface 24 Narrow side 26 Slanted fixing surface 28 Rubber arm 30 First stopper protrusion 32 Second stopper protrusion 34 Cylindrical section 36 Shaft-shaped part 38 Mounting hole 40 Rotation limiting protrusion 42 First retaining piece 44 Second retaining piece 46 Mounting part 48 Mounting hole

Claims

1. An anti-vibration device in which an anti-vibration device body having a structure in which a main rubber elastic body is fixed to the outer peripheral surface of an inner shaft member is inserted into a tubular portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastic body, the main rubber elastic body includes a plurality of rubber arm portions that interconnect the inner shaft member and the tubular portion of the outer member, the rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, A first retaining piece is integrally formed at the openings on both axial sides of the cylindrical portion, protruding inward at a position corresponding to the rubber arm portion in the circumferential direction, and a first retaining portion that prevents the vibration isolation device main body from coming off the cylindrical portion is formed by the abutment of the first retaining piece and the rubber arm portion. A plurality of the first retaining pieces are provided at least on one of the openings of the cylindrical portion, spaced apart from one another in a circumferential direction of the cylindrical portion, and the plurality of first retaining pieces are overlapped with the rubber arm portion in the axial direction, the first retaining piece on one axial side of the cylindrical portion and the first retaining piece on the other axial side are formed at different positions in a circumferential direction of the cylindrical portion and are arranged so as not to overlap with each other when projected in the axial direction, the first retaining piece on one axial side is provided at a position corresponding to a central portion of the rubber arm portion in a circumferential direction of the tubular portion, and the first retaining pieces on the other axial side are provided on both sides of the first retaining piece on one axial side in the circumferential direction of the tubular portion, A vibration-proof device in which the sum of the overlapping areas of the first anti-removal piece on the other axial side and the rubber arm portion is greater than the sum of the overlapping areas of the first anti-removal piece on the one axial side and the rubber arm portion.

2. 2. The vibration-isolating device according to claim 1, wherein a main elastic axis of said rubber arm portion extending in a connecting direction between said inner shaft member and said cylindrical portion is inclined in the axial direction from said inner shaft member side toward said cylindrical portion side.

3. An anti-vibration device in which an anti-vibration device body having a structure in which a main rubber elastomer body is fixed to the outer peripheral surface of an inner shaft member is inserted into a tubular portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastomer body, the main rubber elastic body includes a plurality of rubber arm portions that interconnect the inner shaft member and the tubular portion of the outer member, the rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, A first retaining piece is integrally formed at the openings on both axial sides of the cylindrical portion, protruding inward at a position corresponding to the rubber arm portion in the circumferential direction, and a first retaining portion that prevents the vibration isolation device main body from coming off the cylindrical portion is formed by the abutment of the first retaining piece and the rubber arm portion. a plurality of the first retaining pieces are provided at a distance from one another in a circumferential direction of the cylindrical portion at at least one of the openings of the cylindrical portion, and the plurality of first retaining pieces are overlapped with the rubber arm portion in the axial direction, A vibration-proof device in which a main elastic axis of the rubber arm portion extending in a direction in which the inner shaft member and the tubular portion are connected is inclined in the axial direction from the inner shaft member side toward the tubular portion side.

4. the main rubber elastic body includes a stopper projection projecting from the inner shaft member toward the cylindrical portion between the plurality of rubber arm portions in the circumferential direction, A vibration-damping device as described in any one of claims 1 to 3, wherein a second anti-removal piece is integrally formed in at least one of the openings of the tubular portion and protrudes toward the inner circumference at a position corresponding to the stopper protrusion in the circumferential direction, and a second anti-removal portion is formed by abutment between the second anti-removal piece and the stopper protrusion, which prevents the vibration-damping device main body from coming off the tubular portion.

5. An anti-vibration device in which an anti-vibration device body having a structure in which a main rubber elastomer body is fixed to the outer peripheral surface of an inner shaft member is inserted into a tubular portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastomer body, the main rubber elastic body includes a plurality of rubber arm portions that interconnect the inner shaft member and the tubular portion of the outer member, the rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, A first retaining piece is integrally formed at the openings on both axial sides of the cylindrical portion, protruding inward at a position corresponding to the rubber arm portion in the circumferential direction, and a first retaining portion that prevents the vibration isolation device main body from coming off the cylindrical portion is formed by the abutment of the first retaining piece and the rubber arm portion. a plurality of the first retaining pieces are provided at a distance from one another in a circumferential direction of the cylindrical portion at at least one of the openings of the cylindrical portion, and the plurality of first retaining pieces are overlapped with the rubber arm portion in the axial direction, the main rubber elastic body includes a stopper projection projecting from the inner shaft member toward the cylindrical portion between the plurality of rubber arm portions in the circumferential direction, A second anti-removal piece is integrally formed in at least one of the openings of the tubular portion and protrudes toward the inner circumference at a position corresponding to the stopper protrusion in the circumferential direction, and a second anti-removal portion is formed by abutment between the second anti-removal piece and the stopper protrusion, which prevents the vibration-damping device main body from coming off the tubular portion.

6. A pair of the stopper projections project radially outward from both sides of the inner shaft member, The second retaining piece is provided at a position corresponding to one of the stopper projections, and is formed on one axial opening side of the cylindrical portion with respect to the one of the stopper projections, 6. An anti-vibration device as described in claim 4 or 5, wherein the second anti-detachment piece provided at a position corresponding to the other stopper protrusion is formed on the other axial opening side of the cylindrical portion relative to the other stopper protrusion.

7. The cylindrical portion is provided with a rotation limiting protrusion that protrudes toward an inner circumference on a circumferential side of the rubber arm portion, the rotation limiting projection extends continuously outward in the axial direction of the cylindrical portion beyond the tip of the rubber arm portion protruding from the inner shaft member, An anti-vibration device as described in any one of claims 1 to 6, wherein a rotation limiting mechanism is formed that limits the amount of relative rotation in the circumferential direction between the main rubber elastic body and the tubular portion by engaging the rubber arm portion with the rotation limiting protrusion in the circumferential direction of the tubular portion.

8. An anti-vibration device in which an anti-vibration device main body having a structure in which a main rubber elastomer body is fixed to the outer peripheral surface of an inner shaft member is inserted into a tubular portion of an outer member and assembled in a non-adhesive state, and the inner shaft member and the outer member are elastically connected by the main rubber elastomer body, the main rubber elastic body includes a plurality of rubber arm portions that interconnect the inner shaft member and the tubular portion of the outer member, the rubber arm portions are pre-compressed between the inner shaft member and the cylindrical portion, A first retaining piece is integrally formed at the openings on both axial sides of the cylindrical portion, protruding inward at a position corresponding to the rubber arm portion in the circumferential direction, and a first retaining portion that prevents the vibration isolation device main body from coming off the cylindrical portion is formed by the abutment of the first retaining piece and the rubber arm portion. a plurality of the first retaining pieces are provided at a distance from one another in a circumferential direction of the cylindrical portion at at least one of the openings of the cylindrical portion, and the plurality of first retaining pieces are overlapped with the rubber arm portion in the axial direction, The cylindrical portion is provided with a rotation limiting protrusion that protrudes toward an inner circumference on a circumferential side of the rubber arm portion, the rotation limiting projection extends continuously outward in the axial direction of the cylindrical portion beyond the tip of the rubber arm portion protruding from the inner shaft member, The rubber arm portion engages with the rotation limiting protrusion in the circumferential direction of the tubular portion, thereby forming a rotation limiting mechanism that limits the amount of relative rotation in the circumferential direction between the main rubber elastic body and the tubular portion.

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