An intermediate cylinder 18 is interposed between an inner cylinder 12 and an outer cylinder 14. The inner cylinder has a first bulging portion 20 of a spherical zone shape. The intermediate cylinder has a second bulging portion 22 of a spherical zone shape enclosing the first bulging portion. The inner circumference of the second bulging portion has a first spherical recess 23 corresponding to the first bulging portion. The inner circumference portion of the outer cylinder 14 enclosing the second bulging portion has a second spherical recess 25 corresponding to the second bulging portion. A rubbery elastic member 16 has an inner elastic portion 26 connecting the inner cylinder 12 and the intermediate cylinder 18 and an outer elastic portion 28 connecting the intermediate cylinder 18 and the outer cylinder 14. The axial size D1 of the inner elastic portion is larger than the axial size D2 of the outer elastic portion.

TECHNICAL FIELD

The present invention relates to a vibration-isolating bush to be assembled for use in the suspension mechanism of an automobile and so on.

BACKGROUND ART

In the prior art, the automotive suspension mechanism uses the vibration-isolating bush at a portion connecting the car body and the suspension with a view to attenuating and absorbing the shocks. This vibration-isolating bush is generally provided with a shaft member such as an inner cylinder, an outer cylinder arranged at a spacing outside of the shaft member, and a rubbery elastic member interposed between the shaft member and the outer cylinder to bind the two elastically.

As the suspension mechanism having the vibration-isolating bush of this kind, a multi-link type rear suspension mechanism, as shown inFIG. 15andFIG. 16, is disclosed in the following Patent Document 1. This suspension mechanism is provided with: an axle62for supporting a wheel60rotatably; a pair of front and rear upper links64and66connected at their one-end portions64aand66arockably to an axle62and connected at their other-end portions64band66brockably to a suspension member68acting as a body side member; a pair of front and rear lower links70and72connected at their one-end portions70aand72arockably to the axle62and connected at their other-end portions70band72brockably to the suspension member68; and a toe control link74connected at its one-end portion74arockably to the axle62and connected at its other-end portion74brockably to the suspension member68. Here, letter F designates the front side of the car body, and letter H designates the width direction of the car body.

Moreover, the other-end portions64b,66b,70b,72band74bof the individual links64,66,70,72and74and the suspension member68are connected through vibration-insulating bushes76,78,80,82and84, respectively, and the individual vibration-isolating bushes have their axes p1, p2, p3, p4and p5arranged to along the directions perpendicular to the longitudinal directions r1, r2, r3, r4and r5of the individual links.

In the multi-link type suspension mechanism thus far described, as shown inFIG. 16, the individual links64,66,70,72and74are set at inclined positions in a top plan view. Specifically, the lower link70on the front side is set in a top plan view to the inclined position, at which the inner side of the body width direction H is positioned on the body front side F. The lower link72on the rear side is set in a top plan view to the inclined position, at which the outer side of the body width direction H is positioned on the body front side F. The toe control link74is set in a top plan view to the inclined position, at which the outer side of the body width direction H is positioned on the body front side F.

While the vehicle is running, therefore, forces of various directions are inputted to the vibration-isolating bushes80,82and84, which are coupled mainly to the lower links70and72and the toe control link74. If the suspension mechanism is vertically displaced with respect to the car body, for example, not only the forces in a twisting direction N (as referred toFIG. 2) but also the forces in a prying direction Z (as referred toFIG. 1) are applied to the vibration-isolating bushes80,82and84. If the suspension mechanism is transversely displaced with respect to the car body, on the other hand, not only the forces in a transverse direction Y (as referred toFIG. 1) but also the forces in an axial direction X (as referred toFIG. 1) are applied to the vibration-isolating bushes80,82and84.

In order to improve the riding comfortableness and the steering stability in the vibration-isolating bush of this kind, therefore, it is desired to reduce the spring constants in the twisting direction and in the prying direction while enlarging the spring constants in the transverse direction and in the axial direction.

For this desire, there has been developed the so-called “vibration-isolating bush of a bulge type” (as referred to the following Patent Document 2), in which the inner cylinder is provided at its axially central portion with a bulging portion bulging in the transverse direction so as to reduce the spring constant in the prying direction while enlarging the spring constant in the transverse direction. In order to enhance the spring constant more in the transverse direction, moreover, there is disclosed in the following Patent Document 3 a vibration-isolating bush of the aforementioned bulge type, which is constituted to have an intermediate cylinder between an inner cylinder and an outer cylinder.

Patent Document 2: JP-A-09-100859, and

DISCLOSURE OF THE INVENTION

Problems to be Solved by the Invention

In the vibration-isolating bush disclosed in the aforementioned Patent Document 3, the inner cylinder is provided with a bulging portion of a spherical zone shape, and the intermediate cylinder is also provided with the bulging portion corresponding to the former bulging portion. The intermediate cylinder is provided, respectively on the inner and outer rubbery elastic members, with hollow portions having their leading ends leading to the bulging portions, so that the rigidity in the prying direction is lowered while enhancing the rigidity in the transverse direction.

In the vibration-isolating bush disclosed in that Patent Document, however, the following problem arises because the aforementioned inner and outer rubbery elastic members have the identical axial sizes. Specifically, the vibration-isolating mechanism of this kind is subjected at its outer cylinder, after the rubbery elastic members were vulcanized, to a drawing work so as to eliminate the molding distortion. In the vibration-isolating bush having the intermediate cylinder, however, the rubbery elastic member outside of the intermediate cylinder is compressed, but the intermediate cylinder is hardly reduced in its diameter, so that the rubbery elastic member on the inner side of the intermediate cylinder is not compressed. In the outer rubbery elastic member, therefore, the spring constant in the transverse direction is made higher by the compression than that of the inner rubbery elastic member. With the spring constants of the rubbery elastic members being thus made different between the outer side and the inner side, the spring characteristics are made so nonlinear by the inner rubbery elastic member having the lower spring constant, when the load is inputted in the transverse direction to the vibration-isolating bush, that the load-deflection curve gently rises at an initial stage and then grows steep. Thus, it is impossible to acquire excellent vibration-isolating characteristics.

In the vibration-isolating bush disclosed in that Patent Document, moreover, the outer cylinder is not provided on its inner circumference with a spherical recess corresponding to the bulging portion of the intermediate cylinder, and the aforementioned hollow portions reach the bulging portion. At the time of drawing the outer cylinder, therefore, it is thought that the rubber cannot be compressed homogeneously in the axial direction thereby to deteriorate the durability.

The present invention has been conceived in view of the points thus far described, and has an object to provide a vibration-isolating bush, which can reduce the spring constants in the twisting direction and in the prying direction while retaining the spring constants in the transverse direction and in the axial direction, and which can bring the spring characteristics closer to the linearity against the load input in the transverse direction.

Means for Solving the Problems

According to the invention, there is provided a vibration-isolating bush comprising: a shaft member, an outer cylinder for enclosing the shaft member axially in parallel; and a rubbery elastic member interposed between the shaft member and the outer cylinder. The vibration-isolating bush is constituted:

by comprising an intermediate cylinder interposed between the shaft member and the outer cylinder for enclosing the shaft member axially in parallel;

such that the shaft member has its axially central portion formed into a first bulging portion of a spherical zone shape bulging transversely outward, such that the intermediate cylinder enclosing the first bulging portion has its axially central portion formed into a second bulging portion of a spherical zone shape bulging transversely outward, such that the second bulging portion has its inner circumference formed into a first spherical recess corresponding to the first spherical bulge of the first bulging portion, and such that the inner circumference portion of the outer cylinder enclosing the second bulging portion is formed into a second spherical recess corresponding to the second spherical bulge of the outer circumference of the second bulging portion; and

such that the rubbery elastic member includes an inner elastic portion adhered individually to the outer circumference of the shaft member containing the first spherical bulge and the inner circumference of the intermediate cylinder containing the first spherical recess, thereby to connect the shaft member and the intermediate cylinder, and an outer elastic portion adhered individually to the outer circumference of the intermediate cylinder containing the second spherical bulge and the inner circumference of the outer cylinder containing the second spherical recess, thereby to connect the intermediate cylinder and the outer cylinder, and such that the inner elastic portion is formed to have a larger axial size than that of the outer elastic portion.

In the aforementioned constitution, the outer cylinder can be drawn after the rubbery elastic member was vulcanized, and the outer elastic portion may then be made thicker, before drawn, in the transverse direction than the inner elastic portion, and may be made as thick as the inner elastic portion by the drawing work.

Moreover, the two end portions of the inner elastic portion may be extended so axially outward as to connect the shaft member portion on the axially outer side of the first spherical bulge and the intermediate cylinder portion on the axially outer side of the first spherical recess, and the two end portions of the outer elastic portion may be extended so axially outward as to connect the intermediate cylinder portion on the axially outer side of the second spherical bulge and the outer cylinder portion on the axially outer side of the second spherical recess.

Moreover, it is preferred that the outer cylinder is formed into a straight cylinder shape having an outer circumference of a constant diameter in the axial direction.

Moreover, the shaft member may be made of an inner cylinder of a cylindrical shape, and the inner cylinder may have its at least one axial end portion radially enlarged by a cold-plastic work after the rubbery elastic member was vulcanized.

Moreover, stopper rubber portions may be disposed at the axially end portions of the outer cylinder.

Advantage of the Invention

In the vibration-isolating bush of the invention, at the time of displacement in the prying direction, the shearing deformations are received mainly by the inner elastic portion between the first spherical bulge of the shaft member and the first spherical recess of the intermediate cylinder, and by the outer elastic portion between the second spherical bulge of the intermediate cylinder and the second spherical recess of the outer cylinder so that the spring constant in the prying direction can be effectively reduced. Against the displacement in the axial direction, on the other hand, the rubbery elastic member receives not only the shearing deformation but also the compressive deformation between each spherical bulge and each spherical recess so that the spring constant in the axial direction can be raised.

Moreover, the intermediate cylinder can increase the spring constant in the transverse direction. In case the spring constant in the transverse direction is set equivalent to that of the case of no intermediate cylinder, the rubbery elastic member to be used can be made softer thereby to lower the spring constant in the twisting direction.

Moreover, the outer elastic portion on the outer side of the intermediate cylinder is compressed to have a higher spring constant by drawing the outer cylinder. However, the axial size of the inner elastic portion, as left uncompressed by the drawing work, is set so large that the rise in the spring constant of the outer elastic portion by the drawing work can be compensated. As a result, it is possible to bring the spring constant closer to the linearity against the load input in the transverse direction.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the invention are described in the following with reference to the accompanying drawings.

A vibration-isolating bush10according to a first embodiment is used in the aforementioned multi-link type suspension mechanism shown inFIG. 15andFIG. 16. More specifically, the vibration-isolating bush10is used as a vibration-isolating bush80for connecting the other-end portion70bof a lower link70on the front side and a suspension member68, a vibration-isolating bush82for connecting the other-end portion72bof a lower link72on the rear side and the suspension member68, and a vibration-isolating bush84for connecting the other-end portion74bof a toe control link74and the suspension member68. A description of the entire constitution of the suspension mechanism is omitted, because it has been described hereinbefore.

The vibration-isolating bush10is provided, as shown inFIGS. 1 and 2, with an inner cylinder12acting as a shaft member, an outer cylinder14axially in parallel with and coaxially enclosing the inner cylinder12, a cylindrical rubbery elastic member16interposed between the inner cylinder12and the outer cylinder14, and an intermediate cylinder18enclosing the inner cylinder12axially in parallel and coaxially therewith at an intermediate position between the inner cylinder12and the outer cylinder14. As shown inFIG. 10, the inner cylinder12is so fixed on a bracket1of the suspension member by fastening it with not-shown fastening members such as bolts that its two end faces are clamped by the bracket1. Moreover, the outer cylinder14is fixed by press-fitting it into a cylindrical holder3of the lower link70or the like. As a result, the vibration-isolating bush10connects the lower link70or the like and the bracket1on the suspension member side in a vibration isolating manner.

The inner cylinder12is a cylindrical member made of a metal, and is provided, at a central portion in an axial direction X, as shown inFIGS. 4 and 5, with a first bulging portion20of a spherical zone shape bulging all over the circumference in a transversely outward direction Y1. The outer circumference of the first bulging portion20is formed into a spherical bulge21(as will be called the “first spherical bulge”). Specifically, the first spherical bulge21has such a spherical zone shape as forms an axially central portion of a sphere having a center P on the axis A of the inner cylinder12and as gently continues from the outer circumferences12A of the generally cylindrical portions (i.e., straight cylinder portions having a constant external diameter) at the two axially end portions of the inner cylinder12.

The intermediate cylinder18is a cylindrical member made of a metal thinner than the inner cylinder12and the outer cylinder14, and as shown inFIGS. 1,8and9, its central portion, as enclosing the first bulging portion20, in the axial direction X is bent into a second bulging portion22of a spherical zone shape bulging all over its circumference in the transversely outward direction Y1. The inner circumference of the second bulging portion22is formed into a spherical recess23(as will be called the “first spherical recess”) concentric to (i.e., having the common center P) the first spherical bulge21of the first bulging portion20. The outer circumference of the second bulging portion22is formed into a spherical bulge24(as will be called the “second spherical bulge”) concentric to the first spherical bulge21of the first bulging portion20. The first spherical recess23is formed to gently continue from the inner circumferences18A of the generally cylindrical portions (i.e., straight cylinder portions having constant internal and external diameters) at the two axially end portions of the intermediate cylinder18. The second spherical bulge24is formed to gently continue from the outer circumferences18B of the aforementioned generally cylindrical portions.

The outer cylinder14is a cylindrical member made of a metal, and is formed into a straight cylinder shape having an exterior shape of a circular section and an outer circumference14A of a diameter constant in the axial direction X, as shown inFIGS. 6 and 7. As shown inFIG. 1, the inner circumferential portion of the outer cylinder14enclosing the aforementioned second bulging portion22is formed into a spherical recess25(as will be called the “second spherical recess”) concentric to the second spherical bulge24on the outer circumference side of the second bulging portion22. In the shape after a later-described drawing work, more specifically, an inner circumference14B at the central portion of the outer cylinder14is recessed along and at a constant spacing from the aforementioned second spherical bulge24, into the spherical recess25recessed toward the transversely outward direction Y1. The second spherical recess25is formed into the spherical zone shape forming the central portion of the spherical face, and is formed to gently continue from the inner circumferences14B of the general cylinder portion (i.e., the straight cylindrical portions having a constant internal diameter) in the two axial end portions of the outer cylinder12.

Since this second spherical recess25is formed, the outer cylinder14is formed thinner at its axially central portion than at its two end portions. In the state before the drawing work, as shown inFIG. 7, the second spherical recess25is not the spherical zone strictly, but the centers P are deviated in the transverse direction Y (i.e., a direction perpendicular to the axis A) from the axis A of the outer cylinder14. By the drawing work in the radially reducing directions, the second spherical recess25is formed into the spherical zone shape, in which the center P is positioned on the axis A, as shown inFIG. 1.

As shown inFIG. 1, the rubbery elastic member16is constituted to include an inner elastic portion26for connecting the inner cylinder12and the intermediate cylinder18, and an outer elastic portion28for connecting the intermediate cylinder18and the outer cylinder14. These two elastic portions are made of an identical rubber material, and are connected to each other through a plurality of communication holes30formed in the circumferential direction in the second bulging portion22of the intermediate cylinder18.

The inner elastic portion26is vulcanized and adhered individually to the outer circumferences12A of the inner cylinder12including the first spherical bulge21and to the inner circumferences18A of the intermediate cylinder18including the first spherical recess23. The outer elastic portion28is vulcanized and adhered individually to the outer circumferences18B of the intermediate cylinder18including the second spherical bulge24and to the inner circumferences14B of the outer cylinder14including the second spherical recess25.

The inner elastic portion26is not only filled between the first spherical bulge21and the first spherical recess23but also made to have its two end portions26A and26A so extended in an axially outward direction X1as to connect inner cylinder portions12B closer in the axially outward direction X1than the first spherical bulge21and intermediate cylinder portions18C closer in the axially outward direction X1than the first spherical recess23. Likewise, the outer elastic portion28is not only filled between the second spherical bulge24and the second spherical recess25but also made to have its two end portions28A and28A so extended in the axially outward direction X1as to connect the intermediate cylinder portions18C closer in the axially outward direction X1than the second spherical bulge24and outer cylinder portions14C closer in the axially outward direction X1than the second spherical recess25.

Moreover, the elastic portions26and28are provided at their axial end faces with annular hollow portions32and34, which are depressed in an axially inward direction X2into arcuate sections. The hollow portion32of the inner elastic portion26is made shallower in an axial direction X than the hollow portion34of the outer elastic portion28. As a result, the inner elastic portion26is formed to have a larger axial size D1than the axial size D2of the outer elastic portion28(that is, D1>D2).

As to the thicknesses of the two elastic portions26and28in the transverse direction Y, before the drawing work of the outer cylinder14shown inFIG. 3, the outer elastic portion28has its thickness E2set larger than the thickness E1of the inner elastic portion26(that is, E1<E2). After the drawing work shown inFIG. 1, the outer elastic portion28is compressed in the transverse direction Y so that the thickness E1of the inner elastic portion26and the thickness E2of the outer elastic portion28are set substantially equal to each other (that is, E1=E2).

When the vibration-isolating bush10is to be manufactured, there are separately prepared: the inner cylinder12having the first bulging portion20, as shown inFIGS. 4 and 5; the outer cylinder14having the second spherical recess25in the inner circumference14B, as shown inFIGS. 6 and 7; and the intermediate cylinder18having the second bulging portion22, as shown inFIGS. 8 and 9.

Next, the aforementioned inner cylinder12, outer cylinder14and intermediate cylinder18are arranged in the not-shown mold, and a rubber material is injected into the mold thereby to vulcanize the rubbery elastic member16, as composed of the inner elastic portion26and the outer elastic portion28, between the inner cylinder12and the outer cylinder14. As a result, the vulcanized molding, as shown inFIG. 3, before drawn is obtained.

After this, the outer cylinder14of the aforementioned vulcanized molding is drawn so that it is radially reduced to produce the vibration-isolating bush10shown inFIG. 1. By the drawing work, the outer elastic portion28is compressed in the transverse direction Y to have a higher spring constant. On the other hand, the inner elastic portion26is left uncompressed in the transverse direction Y, because the intermediate cylinder18is not radially reduced in the presence of the outer elastic portion28. However, the inner elastic portion26is set larger in the axial size than the outer elastic portion28(D1>D2), so that the rise in the spring constant by the aforementioned drawing work can be compensated to set the spring constant in the transverse direction Y equivalent at the inner elastic portion26and the outer elastic portion28. As a result, the spring characteristics can be made more linear against the load input to the vibration-isolating bush10in the transverse direction Y so that the desired vibration-isolating characteristics can be exhibited. By making the inner and outer spring constants equivalent, moreover, it is possible to improve the durability of the vibration-isolating bush10against the load input in the transverse direction Y.

With the vibration-isolating bush10of this embodiment and at the time of displacement in a prying direction Z, the inner elastic portion26between the first spherical bulge21of the inner cylinder12and the first spherical recess23of the intermediate cylinder18, and the outer elastic portion28between the second spherical bulge24of the intermediate cylinder18and the second spherical recess25of the outer cylinder14are subjected mainly to shearing deformations. As a result, it is possible to effectively reduce the spring constant in the prying direction Z.

Against the displacement in the axial direction X, on the other hand, the rubbery elastic member16is subjected not only the shearing deformation but also the compression deformation between the spherical bulges21and24and the spherical recesses23and25. As a result, it is possible to raise the spring constant in the axial direction X.

With the intermediate cylinder18, the spring constant in the transverse direction Y is enlarged. In case, therefore, the spring constant in the transverse direction Y is set equivalent to that of the case having no intermediate cylinder, a softer rubbery elastic member16can be used to lower the spring constant in a twisting direction N.

Thus, this vibration-isolating bush10can reduce the spring constants effectively in the prying direction Z and in the twisting direction N, while retaining the spring constants in the axial direction X and in the transverse direction Y. As a result, the spring constant in the vertical direction of the suspension mechanism can be effectively reduced while retaining the spring constant high in the horizontal direction of the suspension mechanism, so that the riding comfortableness can be drastically improved while retaining the steering stability.

In this vibration-isolating bush10, moreover, the axial size D1of the inner elastic portion26is made larger than the axial size D2of the outer elastic portion28. As a result, the inner elastic portion26of a smaller circumference length can retain the contact area with the inner cylinder12accordingly larger thereby to improve the durability.

For the spring constant at the time of displacement in the prying direction Z, on the other hand, the outer elastic portion28having the shorter axial size makes a higher contribution. Between the individual spherical bulges21and24and spherical recesses23and25made concentric, however, the second spherical bulge24and the second spherical recess25, as connected by the outer elastic portion28, on the outer circumference side have larger arcuate lengths in the axial section, as shown inFIG. 1, than the first spherical bulge21and the first spherical recess23on the inner circumference side. At the time of the displacement in the prying direction Z, therefore, the spring constant in the prying direction Z can be reduced by making the shearing deformation more chiefly at the outer elastic portion28.

In this vibration-isolating bush10, moreover, the thickness E1of the inner elastic portion26and the thickness E2of the outer elastic portion28are made equivalent after the drawing work. As a result, the spring constant in the transverse direction Y can be made more equivalent between the inner elastic portion26and the outer elastic portion28so that it can be made closer to the linear spring characteristics.

Moreover, the recessed portion of the inner circumference of the outer cylinder14enclosing the second bulging portion22of the intermediate cylinder18is the second spherical recess25of the spherical shape, and the two end portions28A and28A of the outer elastic portion28are extended to the outer side of the second spherical recess25. At the time of drawing the outer cylinder14, therefore, the outer elastic portion28can be equivalently compressed in the axial direction X thereby to improve the durability.

In the outer cylinder14, the outer circumference14A is formed into the straight cylinder shape having the constant diameter in the axial direction although the inner circumference14B has the second spherical recess25. As a result, a sufficient axial size for the press-fit can be retained between the outer cylinder14and the cylindrical holder3thereby to improve the force to extract the outer cylinder14from the cylindrical holder3.

FIGS. 11 to 13show a vibration-isolating bush10A according to a second embodiment. This embodiment is characterized in that the two end portions12C and12C of the inner cylinder12in the axial direction X are radially enlarged by a cold-plastic working after the rubbery elastic member16was vulcanized so that they are formed as radially enlarged portions36and36.

In the second embodiment, more specifically, the rubbery elastic member16is vulcanized, as shown inFIG. 11, to prepare the vulcanized molding before the drawing work, and the outer cylinder14is then drawn to manufacture the vibration-isolating bush10A, as shown inFIG. 12. Next, the not-shown pressing jig is caused to press the individual end faces of the two end portions12C and12C of the inner cylinder12of the vibration-isolating bush10A in the axial direction X, thereby to form the radially enlarged portions36, at which the end portions12C of the inner cylinder12are thicker than the axially inner portions. The radial expansion by this cold-plastic working is disclosed in JP-A-2003-106359, for example, and can resort to the method disclosed.

By providing those radially enlarged portions36, according to the second embodiment, the area of the end faces of the inner cylinder12can be enlarged while retaining the free length at the rubbery elastic member16, especially, at the end portions26A of the inner elastic portion26. As a result, the facial pressures on the end faces of the inner cylinder12fastened to the bracket1can be lowered. The remaining constitutions and advantages are similar to those of the foregoing first embodiment, and therefore, descriptions thereof are omitted.

FIG. 14shows a vibration-isolating bush10B according to a third embodiment. This embodiment is characterized in that the outer cylinder14is provided at its one axial end portion14D with a flanged portion38extending in the transversely outer direction Y1, and in that the flanged portion38is provided on its axially outer side face38A with a stopper rubber portion40for exhibiting a stopper action between itself and the not-shown bracket. On the other hand, the other axial end portion14E of the outer cylinder14is provided to the end faces not with the flanged portion but directly with a stopper rubber portion42.

The flanged portion38is formed in an annular shape around the whole circumference of the axial end portion14D of the outer cylinder14, and the stopper rubber portion40is also formed in an annular shape around the whole circumference along the flanged portion38. The stopper rubber portion42on the other end side is also formed in an annular shape around the whole circumference of the axial end portion14E of the outer cylinder14. The two stopper rubber portions40and42are integrated of the rubber leading from the aforementioned rubbery elastic member16.

Thus, the stopper rubber portions40and42are formed at the two end portions14D and14E of the outer cylinder14so that they can exhibit stopper action with the bracket holding the inner cylinder12thereby to restrict the excessive displacement of the outer cylinder14in the axial direction X. The remaining constitutions and advantages are similar to those of the foregoing first embodiment, and therefore, descriptions thereof are omitted.

Industrial Applicability

The present invention can be applied to various vibration-isolating bushes such as a vibration-isolating bush to be assembled for use with the suspension mechanism of an automobile or a vibration-isolating bush of a cylindrical shape as an engine mount.

DESCRIPTION OF REFERENCE NUMERALS AND SIGNS