JP7145039B2 - Anti-vibration device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator, and more particularly to a vibration isolator capable of facilitating the design of spring characteristics in the vertical axis direction of a bush and regulating the rotation of the bush.

2. Description of the Related Art A vibration damping device is known in which a bush, which has a holding hole through which a stabilizer bar passes and is made of a tubular rubber-like elastic body, is attached to the vehicle body side using a bracket. If the inner surface of the bracket that surrounds and presses the outer peripheral surface of the bush is made substantially circular when viewed from the axial direction, the bush may rotate with respect to the bracket when a load is input from the stabilizer bar to the bush. On the other hand, in the anti-vibration device disclosed in Patent Document 1, the main body of the bush is surrounded and pressed by the inner surface of a substantially circular shape, and the protruding portion extends radially outward from the extension portion extending in the axial direction of the main body in a rectangular shape. The protrusion is protruded in shape, and the protrusion is sandwiched between the restricting portions of the bracket from both sides in the circumferential direction to restrict the rotation of the bush with respect to the bracket.

JP 2008-273467 A

However, in the technique of Patent Document 1, when the projecting direction of the protrusion is the horizontal axis, the protrusion is sandwiched between the restricting parts from the vertical axis direction. It has a big effect on the characteristics. Further, when the projecting direction of the protrusion is the vertical axis direction, the restricting part is positioned in the vertical axis direction of the extension part, so the reaction force from the restricting part to the extension part has a great influence on the spring characteristics of the bush. Since it is necessary to design the spring characteristics of the bush in the vertical axis direction in consideration of these reaction forces and the spring characteristics of the main body, there is a problem that the design becomes relatively difficult.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems, and to provide a vibration damping device that facilitates the design of the spring characteristics of the bush in the vertical axis direction and that can regulate the rotation of the bush. do.

In order to achieve this object, the vibration damping device of the present invention comprises a bush composed of a cylindrical rubber-like elastic body having a holding hole through which a stabilizer bar passes, and a circular bushing seen from the axial direction of the holding hole. and a bracket that is not adhered to the bushing, the bushing comprising: a main body that is surrounded by the circular inner surface and pressed against the outer peripheral surface; and an extension that extends the main body in the axial direction. and, in a state where the body is pressed against the circular inner surface while being arranged radially outwardly of the extension portion, part of the outer peripheral shape of the bush is drawn from an imaginary circle centered on the axis of the holding hole. a protruding portion that protrudes radially outward, the protruding portion being formed along a vertical axis and extending from the main body in a horizontal axis direction perpendicular to the axis and the vertical axis. The brackets are formed along the vertical axis and arranged on both circumferential sides of the overhanging outer surface so as to face the overhanging outer surface in the horizontal axis direction. The pair of regulation surfaces are arranged apart from each other in the horizontal axis direction, and the protruding outer surface is a pair of parts facing the pair of regulation surfaces in the horizontal axis direction, respectively. is .

According to the vibration isolator of claim 1, a part of the outer peripheral shape of the bush projects radially outward by the projecting portion in a state in which the outer peripheral surface of the main body of the bush is pressed against the circular inner surface of the bracket. The overhanging outer surface of the overhanging portion is formed along the vertical axis and is located outside the main body in the horizontal axis direction. Since the bracket has a pair of restricting surfaces arranged on both sides of the overhanging outer surface in the circumferential direction so as to face the overhanging outer surface in the horizontal axis direction, when the bush is rotated with respect to the bracket, the overhanging outer surface is regulatory. Thereby, the rotation of the bush with respect to the bracket can be restricted.

Further, the rotation of the bush is regulated by a protruding portion arranged radially outside of the extended portion axially extending from the main body pressed against the circular inner surface. Therefore, even if the bush is provided with a projecting portion that restricts the rotation of the bush, the main body can be surrounded and pressed by the circular inner surface that is circular when viewed from the axial direction. Furthermore, since the overhanging outer surface and the restricting surface are formed along the vertical axis and the overhanging outer surface is positioned outside the main body in the horizontal axis direction, when a load is applied to the bushing in the vertical axis direction, Reaction force applied to the projecting outer surface can be suppressed. This allows the spring properties of the bush in the vertical axis to depend primarily on the spring properties of the body pressed against the circular inner surface. Therefore, it is possible to easily design the spring characteristics of the bush in the vertical axis direction, and to restrict the rotation of the bush.
The pair of restricting surfaces are arranged apart from each other in the horizontal axis direction. The protruding outer surface is a pair of parts facing the pair of restricting surfaces in the horizontal axis direction. As a result, when a load is applied to the bush in the vertical direction, the reaction force received by the overhanging outer surface from the restricting surface can be made the same on both sides in the horizontal direction.

According to the vibration isolator of claim 2, in a state in which the main body is pressed against the circular inner surface, the restricting surfaces located on both sides of the overhanging outer surface in the circumferential direction come into contact with the overhanging outer surface. Thereby, in addition to the effect of claim 1, it is possible to prevent the bush from rotating with respect to the bracket.

According to the vibration isolator according to claim 3 , the interval between the pair of restricting surfaces is larger than the interval between the pair of overhanging outer surfaces in the no-load state of the main body over the entire length in the vertical axis direction. This makes it easier to insert the bush having the pair of overhanging outer surfaces into the bracket having the pair of restricting surfaces in the vertical axis direction. Therefore, in addition to the effect of claim 1 or 2 , the assembling workability of the bush to the bracket can be improved.

According to the vibration isolator according to claim 4 , the overhanging portion has a projection that protrudes from a portion of the overhanging outer surface and contacts the restricting surface. This protrusion allows the bushing to be hardly rotated with respect to the bracket. Furthermore, since the protrusion is provided on a portion of the overhanging outer surface, resistance when inserting the bushing into the bracket can be reduced. Therefore, in addition to the effects of claim 3 , it is possible to further suppress the rotation of the bush while securing workability in assembling the bush to the bracket.

According to the vibration isolator of claim 5 , the regulation surface and the overhanging outer surface are formed parallel to the vertical axis. Accordingly, in addition to the effect of any one of claims 1 to 4 , the reaction force received by the overhanging outer surface from the restricting surface when a load is applied from the stabilizer bar to the bush in the vertical axis direction can be reduced.

According to the vibration isolator of claim 6 , the distance between the pair of regulating surfaces is smaller on one side in the vertical axis direction than the distance between the pair of overhanging outer surfaces when the main body is in an unloaded state, and the distance on the other side in the vertical axis direction is smaller. big on the side. As a result, by inserting the pair of overhanging outer surfaces of the bush between the pair of regulating surfaces of the bracket toward one side in the vertical axis direction, resistance during insertion can be reduced in the initial stage of insertion, and the assembled state In the case, the overhanging outer surface is pressed from the restricting surface, making it more difficult to rotate the bush. Therefore, in addition to the effect of claim 1 or 2 , it is possible to further suppress the rotation of the bush while securing workability of assembling the bush to the bracket.

According to the vibration isolator of claim 7 , the outer peripheral surface of the main body in an unloaded state is formed in an elliptical or elliptical shape elongated in the vertical axis direction in a cross section perpendicular to the axial center. As a result, when the outer peripheral surface of the main body is pressed against the circular inner surface, the main body is pre-compressed in the vertical axis direction, so a gap is created between the main body and the circular inner surface of the stabilizer bar or bracket when a load is applied in the vertical axial direction. It is possible to suppress the occurrence of tapping sound.

However, when the elliptical or elliptical main body rotates due to the load input, the amount of precompression of the main body in the vertical axis direction changes, and the spring characteristics of the main body change. However, since the rotation of the bush can be regulated by the regulating surface and the projecting outer surface, in addition to the effect of any one of claims 1 to 6 , it is possible to suppress changes in the spring characteristics of the main body due to changes in the amount of precompression.

It is a front view of the anti-vibration device before assembly in the first embodiment of the present invention. FIG. 4 is a cross-sectional view perpendicular to the axial direction of the bush; (a) is a front view of the vibration isolator after assembly, and (b) is a cross-sectional view of the vibration isolator taken along line IIIb-IIIb in FIG. 3(a). It is a front view of the anti-vibration device in 2nd Embodiment. It is a front view of the anti-vibration device in 3rd Embodiment. It is a cross-sectional view perpendicular to the axial direction of the vibration isolator.

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. First, a vibration isolator 1 according to a first embodiment will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is a front view of the anti-vibration device 1 before assembly. FIG. 2 is a cross-sectional view perpendicular to the axial direction at the central portion of the bush 10 in the axial direction.

As shown in FIG. 1, the anti-vibration device 1 is for elastically supporting a stabilizer bar 2 on the vehicle body side (not shown). The anti-vibration device 1 includes a bushing 10 having a holding hole 11 through which the stabilizer bar 2 passes and made of a tubular rubber-like elastic body, and a bracket 20 for holding the bushing 10 on the vehicle body side. The stabilizer bar 2 is a shaft-shaped steel material having a substantially circular cross section, and is arranged in the horizontal direction.

1, 2, and FIG. 3(a), which will be described later, show a vertical axis V of the vibration isolator 1 attached to the vehicle body, and a vibration isolator perpendicular to the axis C and the vertical axis V of the holding hole 11. A horizontal axis H of the device 1 is shown. In the following description, the axial direction of the axis C is defined as the axial direction, the axial direction of the vertical axis V is defined as the vertical direction, and the axial direction of the horizontal axis H is defined as the horizontal direction. 1 and the like are described as the upward direction of the vibration isolator 1, and the downward direction of the paper as the downward direction of the vibration isolator 1. good.

The bushing 10 is provided with a cut portion 12 that divides the bushing 10 in the circumferential direction at a position of about 45° with respect to the vertical axis V and the horizontal axis H in a state where the bushing 10 is attached to the stabilizer bar 2 and the bracket 20 . The bush 10 is attached to the stabilizer bar 2 while widening the cut portion 12 so that the inner peripheral surface of the holding hole 11 of the bush 10 contacts the outer peripheral surface of the stabilizer bar 2 . In addition, the bush 10 and the stabilizer bar 2 are non-bonded. Also, a load in the vertical axis direction is mainly input from the stabilizer bar 2 to the anti-vibration device 1 (bush 10).

As shown in FIGS. 1 and 2, the bushing 10 includes a main body 13 whose outer peripheral surface 13a is surrounded by a bracket 20 and pressed, and an extension part extending on both sides of the main body 13 in the axial direction with the same cross-sectional shape. 13b, a flange portion 14 projecting radially outward from the outer peripheral surface of the extension portion 13b, and projecting portions 15 and 16 projecting portions of the flange portion 14 so as to extend radially outward. Each of these parts is integrally molded.

The outer peripheral surface 13a of the main body 13 in an unloaded state is formed in a substantially oval shape (a shape in which a pair of semicircles are connected by a pair of parallel straight lines) elongated in the vertical axis direction in a cross section perpendicular to the axis C. That is, the radius R2 of the main body 13 on the vertical axis V is set larger than the radius R1 on the horizontal axis H of the main body 13 . The flange portion 14 is a portion that protrudes by a substantially constant amount from the outer peripheral surface over the entire circumference of the extension portion 13b. That is, the outer peripheral shape of the flange portion 14 in the no-load state of the bush 10 is substantially oval.

The projecting portions 15 and 16 are portions arranged radially outward of the extension portion 13b. In each drawing, a boundary B between the projecting portions 15, 16 and the flange portion 14 is indicated by a chain double-dashed line. The protruding portions 15 and 16 project the lower left and lower right portions of the flange portion 14 radially outward in a triangular shape.

The protruding portions 15 and 16 have protruding outer surfaces 17 and 18 that extend downward from a pair of parallel straight portions of the flange portion 14 whose outer peripheral surface is substantially oval in the no-load state. The projecting outer surfaces 17 and 18 are formed along the vertical axis V. As shown in FIG. More specifically, the projecting outer surfaces 17 and 18 are formed parallel to the vertical axis V when the bush 10 is in an unloaded state. Further, the projecting outer surfaces 17 and 18 are located outside the main body 13 in the horizontal axis direction.

The bracket 20 includes a first bracket 21 that presses the upper half of the main body 13 and a second bracket 22 that presses the lower half of the main body 13 . The first bracket 21 is a substantially semi-cylindrical member having a semi-circular first circular inner surface 23 centered on the virtual point C1 when viewed from the axial direction. The virtual point C1 overlaps the axis C when the bracket 20 is attached to the bush 10. As shown in FIG. Fastened portions 25 protrude outward in the horizontal axis direction from the lower ends of the first brackets 21 .

The second bracket 22 is a member having a semicircular second circular inner surface 24 centered on the virtual point C2 when viewed from the axial direction, and a substantially rectangular outer surface. The imaginary point C2 overlaps with the axis C when the bracket 20 is attached to the bush 10. As shown in FIG. The second bracket 22 includes a fastened portion 26 projecting outward in the horizontal axial direction from the upper end, and a pair of restricting portions 27 and 28 that are spaced apart in the horizontal axial direction and protrude axially. . A pair of restricting portions 27 and 28 are provided on both sides of the second bracket 22 in the axial direction (see FIG. 3B).

The regulating portions 27 and 28 have a pair of regulating surfaces 29 and 30 facing each other while being separated in the horizontal direction. The restricting surfaces 29 and 30 are formed along the vertical axis V. As shown in FIG. More specifically, the restricting surfaces 29 and 30 are formed parallel to the vertical axis V. As shown in FIG. A horizontal distance L1 between the restricting surfaces 29 and 30 is set slightly larger than a horizontal distance L2 between the overhanging outer surfaces 17 and 18 when the bush 10 is in an unloaded state.

To assemble the vibration isolator 1, first, the first bracket 21 and the second bracket 22 are inserted between the flange portion 14 and the overhanging portions 15 and 16, and the first circular inner surface 23 and the second circular inner surface 24 are aligned. It is brought into contact with the outer peripheral surface 13 a of the main body 13 . At this time, the bush 10 having the pair of projecting outer surfaces 17 and 18 is inserted between the pair of restricting surfaces 29 and 30 . Since the interval L1 between the restricting surfaces 29 and 30 is larger than the interval L2 between the overhanging outer surfaces 17 and 18 in the unloaded state, the bush 10 can be easily inserted between the restricting surfaces 29 and 30 . Thereby, the assembling workability of the bush 10 to the bracket 20 can be improved.

Next, while the first circular inner surface 23 and the second circular inner surface 24 are in contact with the outer peripheral surface 13a, the fastened portion 25 of the first bracket 21 and the fastened portion 26 of the second bracket 22 are connected by the bolt 31 and the nut. 32 to fasten. As a result, the first circular inner surface 23 and the second circular inner surface 24 press the outer peripheral surface 13a to assemble the bracket 20 to the bush 10, and the vibration isolator 1 is assembled. Note that the first circular inner surface 23 and the second circular inner surface 24 are not adhered to the outer peripheral surface 13a.

Next, with reference to FIGS. 3(a) and 3(b), the vibration isolator 1 after assembly, in which the bracket 20 is attached to the bush 10, will be described. FIG. 3(a) is a front view of the vibration isolator 1 after assembly. FIG. 3(b) is a cross-sectional view of the vibration isolator 1 taken along line IIIb--IIIb of FIG. 3(a).

As shown in FIGS. 3(a) and 3(b), when the fastened portions 25 and 26 are fastened, the center of the first circular inner surface 23 and the second circular inner surface 24 becomes the axis C. As shown in FIG. A radius R3 from the axis C to the first circular inner surface 23 or the second circular inner surface 24 is larger than the radius R1 on the horizontal axis H of the main body 13 and smaller than the radius R2 on the vertical axis V of the main body 13. is set. Therefore, when the bracket 20 is assembled to the bush 10, the main body 13, which has a substantially elliptical shape in a no-load state, is elastically deformed into a substantially circular shape centered on the shaft center C when viewed in the axial direction, and the main body 13 is the main body. precompressed in the vertical direction.

Along with this elastic deformation of the main body 13, the outer peripheral surface of the flange portion 14 is also elastically deformed into a substantially circular shape centering on the axis C when viewed in the axial direction. A boundary B between the flange portion 14 and the projecting portions 15 and 16 forms an imaginary circle centered on the axis C. As shown in FIG. Therefore, in a state where the main body 13 is pressed against the first circular inner surface 23 and the second circular inner surface 24, part of the outer peripheral shape of the bush 10 (lower left portion and lower right portion) protrudes from the virtual circle (boundary B). 15 and 16 protrude radially outward.

Restricting surfaces 29 and 30 of restricting portions 27 and 28 are arranged on both circumferential sides of projecting outer surfaces 17 and 18 of projecting portions 15 and 16, respectively. Therefore, as the load is input from the stabilizer bar 2 to the bushing 10, the first circular inner surface 23 or the second circular inner surface 24 slides on the outer peripheral surface 13a, and the bushing 10 tends to rotate about the axis C with respect to the bracket 20. At this time, the projecting outer surfaces 17 and 18 come into contact with the restricting surfaces 29 and 30 . Thereby, the rotation of the bush 10 with respect to the bracket 20 can be restricted.

Further, the rotation of the bush 10 is controlled by the projecting portions 15 and 16 arranged radially outside of the extension portion 13b extending in the axial direction of the main body 13 pressed against the first circular inner surface 23 and the second circular inner surface 24. Regulating. Therefore, even if the bush 10 is provided with the projecting portions 15 and 16 for restricting the rotation of the bush 10, the main body 13 is supported by the substantially circular first circular inner surface 23 and the second circular inner surface 24 centering on the axis C. It can be surrounded and pressed.

Furthermore, the overhanging outer surfaces 17, 18 and the restricting surfaces 29, 30 are formed along the vertical axis V, and the overhanging outer surfaces 17, 18 are positioned outside the main body 13 in the horizontal axis direction. It is possible to suppress the reaction force that the overhanging outer surfaces 17 and 18 receive from the regulating surfaces 29 and 30 when a load is applied in the vertical axis direction. This allows the spring properties of the bush 10 in the vertical axis to depend primarily on the spring properties of the body 13 pressed against the first circular inner surface 23 and the second circular inner surface 24 . Therefore, it is possible to easily design the spring characteristics of the bush 10 in the vertical axis direction, and to restrict the rotation of the bush 10 .

By suppressing the rotation of the bush 10 by the overhanging outer surfaces 17, 18 and the restricting surfaces 29, 30, the outer peripheral surface 13a of the main body 13 is worn by rubbing the first circular inner surface 23 and the second circular inner surface 24 with the outer peripheral surface 13a. can be suppressed. Further, when the bushing 10 rotates and the cut portion 12 approaches the vertical axis V, a tensile stress is generated on both sides of the cut portion 12 when a load is applied to the bush 10 in the vertical direction, and the cut portion 12 tends to widen. Rotation of the bush 10 can be suppressed by the overhanging outer surfaces 17, 18 and the restricting surfaces 29, 30, so that the cut portion 12 can be prevented from widening.

Further, since the substantially oval main body 13 is pre-compressed in the vertical axis direction in a no-load state, when a load is applied to the bush 10 in the vertical axis direction, the outer peripheral surface of the stabilizer bar 2, the first circular inner surface 23, the second It is possible to suppress the generation of a tapping sound due to a gap between the circular inner surface 24 and the main body 13. - 特許庁However, when the main body 13, which is elongated in the vertical direction and has a substantially oval shape, rotates, the amount of precompression of the main body 13 in the vertical direction changes, and the spring characteristics of the main body 13 change. Also, the main body 13, which is elongated in the vertical axis direction and has a substantially oval shape, rotates about 45 degrees, and the rotation may stop when the cut portion 12 approaches the vertical axis V. As shown in FIG. If it does so, the cut part 12 will become easy to spread. By suppressing the rotation of the substantially oval main body 13, it is possible to suppress the change in the spring characteristics of the main body 13 due to the change in the amount of precompression, and to make the cut portion 12 less likely to widen.

Further, since the generally oval body 13 is vertically pre-compressed by the first circular inner surface 23 and the second circular inner surface 24, the extensions are not constrained by the first circular inner surface 23 and the second circular inner surface 24. 13b slightly expands radially outward. Then, the pair of projecting outer surfaces 17 and 18 come into contact with the pair of restricting surfaces 29 and 30, respectively. Thereby, the bush 10 can be hardly rotated with respect to the bracket 20. - 特許庁

Since the projecting outer surfaces 17, 18 and the restricting surfaces 29, 30 are parallel to the vertical axis V, the reaction force received by the projecting external surfaces 17, 18 from the restricting surfaces 29, 30 when a load is applied to the bush 10 in the vertical axis direction is reduced. (minimum) possible. As a result, it is possible to further reduce the influence of the reaction force that the overhanging outer surfaces 17 and 18 receive from the restricting surfaces 29 and 30 on the spring characteristics of the bush 10 when a load is applied in the vertical axis direction. Therefore, it is possible to more easily design the spring characteristics of the bush 10 in the vertical axis direction.

Also, the bush 10 is inserted between a pair of regulating surfaces 29 and 30 facing apart in the horizontal axis direction. As a result, when a load is applied to the bush 10 in the vertical axis direction, the reaction force received from the restricting surfaces 29 and 30 can be applied equally to the overhanging outer surface 17 and the overhanging outer surface 18 (both sides of the bush 10 in the horizontal axis direction). As a result, the influence of the reaction force received by the projecting outer surfaces 17 and 18 on the spring characteristics of the bush 10 when a load is applied in the vertical axis direction can be reduced. Therefore, it is possible to further facilitate the design of the spring characteristics of the bush 10 in the vertical axis direction.

Next, a second embodiment will be described with reference to FIG. In the first embodiment, the case where the overhanging outer surfaces 17 and 18 of the bush 10 expanded by being pressed by the bracket 20 contact the restricting surfaces 29 and 30 has been described. On the other hand, in the second embodiment, a case will be described in which projections 42 protruding from portions of overhanging outer surfaces 17 and 18 come into contact with restricting surfaces 29 and 30 . The same reference numerals are given to the same parts as in the first embodiment, and the following description is omitted. FIG. 4 is a front view of a vibration isolator 40 according to the second embodiment. In addition, in FIG. 4, the projection 42 in the no-load state is indicated by a chain double-dashed line.

As shown in FIG. 4, the bushing 41 of the vibration isolator 40 includes a main body 13 whose outer peripheral surface 13a is pressed against the bracket 20, and extensions 13b extending on both sides of the main body 13 in the axial direction with the same cross-sectional shape. , a flange portion 14 that protrudes radially outward from the outer peripheral surface of the extension portion 13b, projecting portions 15 and 16 that project a part of the flange portion 14 so as to extend radially outward, and the projecting portion 15. , 16 and a plurality of protrusions 42 protruding from portions of the overhanging outer surfaces 17, 18 of the outer surfaces 17,18.

The projection 42 is a part of the projecting portions 15 and 16 and is made of a rubber-like elastic material. The protrusion 42 contacts the restricting surfaces 29 and 30 in a state where the outer peripheral surface 13 a is pressed by the first circular inner surface 23 and the second circular inner surface 24 and the bracket 20 is assembled to the bushing 41 . The protrusion 42 can prevent the bush 41 from rotating with respect to the bracket 20 .

In particular, since a plurality of protrusions 42 are provided apart from each other in the vertical axis direction, the reaction force received from the restricting surfaces 29 and 30 when the bush 41 is about to rotate can be dispersed among the plurality of protrusions 42 . As a result, it is possible to prevent one protrusion 42 from being greatly crushed, so that the amount of rotation of the bush 41 can be reduced according to the amount of crushing of the protrusion 42 .

Furthermore, as in the first embodiment, by bringing the overhanging outer surfaces 17, 18 of the bush 41 expanded by being pressed by the bracket 20 into contact with the regulating surfaces 29, 30, the projection 42 is more strongly applied to the regulating surfaces 29, 30. can be pushed. This makes it more difficult for the bush 41 to rotate with respect to the bracket 20 .

Further, the distance L1 between the pair of restricting surfaces 29 and 30 is larger than the distance L2 between the pair of overhanging outer surfaces 17 and 18 in the unloaded state (see FIG. 1), and projections 42 are formed on a part of the overhanging outer surfaces 17 and 18. is provided. Thereby, the resistance when inserting the bush 41 between the restricting surfaces 29 and 30 can be reduced. Further, when viewed from the axial direction, the protrusion 42 in the unloaded state is formed in a wedge shape with a long slope in the insertion direction of the bush 41 between the regulating surfaces 29 and 30 (lower side of the paper in FIG. 4). Therefore, resistance when inserting the bush 41 between the restricting surfaces 29 and 30 can be made smaller. As a result, even if the protrusion 42 that contacts the restricting surfaces 29 and 30 is provided, it is possible to secure workability in assembling the bush 41 to the bracket 20 .

Next, a third embodiment will be described with reference to FIG. In the first embodiment, the case where the overhanging outer surfaces 17, 18 and the restricting surfaces 29, 30 are parallel to the vertical axis V has been described. On the other hand, in the third embodiment, the case where the projecting outer surfaces 52 and 53 are non-parallel to the vertical axis V will be described. The same reference numerals are given to the same parts as in the first embodiment, and the following description is omitted. FIG. 5 is a front view of a vibration isolator 50 according to the third embodiment. FIG. 6 is a cross-sectional view perpendicular to the axial direction at the central portion of the vibration isolator 50 in the axial direction. In FIG. 5, the protruding outer surfaces 52 and 53 in the no-load state are indicated by two-dot chain lines.

As shown in FIGS. 5 and 6, the overhanging outer surfaces 52 and 53 of the bush 51 of the vibration isolator 50 are along the vertical axis V and slightly inclined with respect to the vertical axis V when the bush 10 is in an unloaded state. formed. When the bush 10 is in a no-load state, the interval in the horizontal axis direction between the overhanging outer surfaces 52 and 53 is closer to the other side in the vertical axis direction (the lower side in FIG. 5) than the interval L3 on the one side in the vertical axis direction (upper side in FIG. 5). side) is large. Further, the projecting outer surfaces 52 and 53 are located outside the main body 13 in the horizontal axis direction.

The bracket 55 of the antivibration device 50 includes a first bracket 56 that presses the upper side of the main body 13 and a second bracket 57 that presses the lower side of the main body 13 . The first bracket 56 is a member having a substantially U-shaped inner surface including a semicircular first circular inner surface 58 centered on the axis C when viewed from the axial direction. The first bracket 56 includes a fastened portion 25 projecting outward in the horizontal axial direction from the lower end, and a pair of restricting portions 27 and 28 spaced apart in the horizontal axial direction and protruding axially. . The pair of restricting portions 27 and 28 are provided on both sides of the first bracket 56 in the axial direction.

The second bracket 57 is a member having an arcuate second circular inner surface 59 centered on the axis C when viewed from the axial direction. The second bracket 57 is inserted between the substantially U-shaped inner surfaces of the first bracket 56 . The first circular inner surface 58 and the second circular inner surface 59 form a substantially circular inner surface centered on the axis C. As shown in FIG. The second bracket 57 includes a fastened portion 26 that contacts the lower surface of the fastened portion 25 and is fastened to the fastened portion 25 by a bolt 31 and a nut 32 .

According to the vibration isolator 50 as described above, when the bush 51 is in a no-load state, the distance between the overhanging outer surfaces 52 and 53 on one side in the vertical axis direction is greater than the distance L1 between the pair of restricting surfaces 29 and 30. L3 is small, and the interval L4 on the other side of the overhanging outer surfaces 52 and 53 in the vertical axis direction is large. Thus, by inserting the pair of overhanging outer surfaces 52 and 53 of the bush 51 between the pair of restricting surfaces 29 and 30 toward one side in the vertical axis direction, the insertion resistance can be reduced at the initial stage of insertion. .

Furthermore, when the bush 51 is assembled with the bracket 55 , the overhanging outer surfaces 52 and 53 are pressed by the restricting surfaces 29 and 30 , so that the bush 51 can be made more difficult to rotate with respect to the bracket 55 . Therefore, it is possible to further suppress the rotation of the bush 51 while ensuring workability of assembling the bush 51 to the bracket 55 .

Since the main body 13 is pre-compressed by the substantially U-shaped inner surface of the first bracket 56 and the arc-shaped inner surface of the second bracket 57 which is less than a semicircle, the substantially U-shaped inner surface and the arc-shaped inner surface The boundary portion is recessed radially outward. The concavity of the boundary portion is positioned at approximately 45° to the vertical V and horizontal H axes. Therefore, when the main body 13, which is elongated in the vertical direction and has a substantially elliptical shape, rotates, the long axis of the ellipse of the main body 13 fits into the recess at the boundary, and the main body 13 tends to stop at a position rotated by about 45°. Become. As a result, the rotation of the cut portion 12 stops when it approaches the vertical axis V, and the cut portion 12 of the bush 51 tends to widen, and the amount of precompression of the main body 13 in the vertical axis direction changes, and the spring characteristics of the main body 13 change. It may change. On the other hand, since the rotation of the main body 13 can be suppressed by the overhanging outer surfaces 52, 53 and the restricting surfaces 29, 30, it is possible to suppress the change in the spring characteristics of the main body 13 due to the change in the precompression amount, and the cut portion 12 can be reduced. It can be made more difficult to spread.

The present invention has been described above based on the embodiments, but the present invention is not limited to the above-described embodiments, and it is easily understood that various modifications and improvements are possible without departing from the scope of the present invention. It can be inferred. For example, the shape of each part such as the bushes 10, 41, 51 and the brackets 20, 55 may be changed as appropriate. The bracket 55 in the third embodiment may be attached to the bushes 10 and 41 in the first and second embodiments. Further, the main body 13 in a no-load state when viewed in the axial direction may be formed in a substantially elliptical shape or a substantially circular shape that is elongated in the vertical direction. When the substantially elliptical main body 13 is used, substantially the same configuration and effects as when using the substantially elliptical main body 13 are exhibited.

Further, the first circular inner surfaces 23, 58 and the second circular inner surfaces 24, 59 are not limited to perfect circles centered on the axis C when viewed in the axial direction. If the main body 13 is rotatable with respect to the brackets 20 and 55 in the absence of the projecting portions 15 and 16 and the restricting portions 27 and 28, the first circular inner surface and the second circular inner surface may be substantially elliptical or substantially oval. You can make it into a shape.

Although the said form demonstrated the case where one place of the circumferential direction of bush 10,41,51 was divided by the cut part 12, it is not necessarily restricted to this. The bushes 10, 41, and 51 may be divided at two locations in the circumferential direction by the cut portion 12, or the cut portion 12 may be omitted.

In the above-described embodiment, the restricting portions 27 are provided on the horizontal axial direction outer sides of the protruding portions 15 and 16 that protrude the lower left and lower right portions of the outer peripheral shapes of the bushes 10, 41 and 51 from the imaginary plane (boundary B) in a triangular shape. , 28 have been described, the arrangement is not necessarily limited to this, and the positions and shapes of the overhanging portion (overhanging outer surface) and the restricting portion (restricting surface) may be changed as appropriate. For example, the projecting portion 16 and the restricting portion 28 in the lower right portion may be omitted, the restricting portion 27 and the restricting surface 29 may be extended upward, and the projecting portion and projecting outer surface which contact the extended portion may be replaced with the bushing 10, It may be provided in the upper left portion of the outer peripheral shape of 41 and 51 .

In the above embodiment, the bushings 10, 41, 51 are integrally molded, but the material may be partially changed. For example, the rubber-like elastic body forming the inner peripheral surface of the holding hole 11 may be made of a material that easily slides on the stabilizer bar 2 . Further, the rubber-like elastic body forming the outer peripheral surface 13 a of the main body 13 may be made of a material that does not slip easily with respect to the brackets 20 and 55 . This makes it more difficult for the bushes 10, 41, 51 to rotate with respect to the brackets 20, 55. FIG.

In the third embodiment, the space L4 on the other side in the vertical axis direction between the pair of overhanging outer surfaces 52 and 53 is larger than the space L3 on one side in the vertical axis direction between the pair of overhanging outer surfaces 52 and 53 in the no-load state. , the case where the pair of restricting surfaces 29 and 30 are parallel to each other has been described, but this is not necessarily the case. In a no-load state, the protruding outer surfaces 52 and 53 are parallel to each other, and the gap on the other side of the regulation surfaces 29 and 30 in the vertical axis direction is larger than the gap on the one side of the regulation surfaces 29 and 30 in the vertical axis direction. can be

Reference Signs List 1, 40, 50 anti-vibration device 2 stabilizer bar 10, 41, 51 bush 11 holding hole 13 main body 13a outer peripheral surface 13b extension 15, 16 overhang 17, 18, 52, 53 overhang outer surface 20, 55 bracket 23, 58 first circular inner surface (part of circular inner surface)
24, 59 Second circular inner surface (part of circular inner surface)
29, 30 regulation surface 42 projection

Claims (7)

a bush composed of a tubular rubber-like elastic body having a holding hole through which the stabilizer bar passes;
a bracket that has a circular inner surface that is circular when viewed from the axial direction of the holding hole and that is not adhered to the bush;
the bush includes a main body whose outer peripheral surface is surrounded by the circular inner surface and pressed;
an extension portion that extends the main body in an axial direction;
In a state where the main body is pressed against the circular inner surface while being arranged radially outwardly of the extension portion, a portion of the outer peripheral shape of the bush is radially expanded from a virtual circle centered on the axis of the holding hole. a protruding portion that protrudes outward,
the overhanging portion is formed along a vertical axis and has an overhanging outer surface positioned outside the main body in a horizontal axis direction perpendicular to the axis and the vertical axis;
The bracket is formed along the vertical axis and has a pair of restricting surfaces arranged on both circumferential sides of the overhanging outer surface so as to face the overhanging outer surface in the horizontal axis direction ,
a pair of the regulation surfaces are arranged apart from each other in the horizontal axis direction;
The anti-vibration device , wherein the protruding outer surface is a pair of parts facing the pair of restricting surfaces in the horizontal axis direction . 2. The vibration isolator according to claim 1, wherein the protruding outer surface is in contact with the restricting surfaces positioned on both sides in the circumferential direction in a state where the main body is pressed against the circular inner surface. 3. The apparatus according to claim 1, wherein the interval between the pair of restricting surfaces is larger than the interval between the pair of overhanging outer surfaces in the no-load state of the main body over the entire length in the vertical axis direction. Anti-vibration device. 4. The vibration damping device according to claim 3 , wherein the overhanging portion has a projection that protrudes from a portion of the overhanging outer surface and contacts the regulation surface. 5. A vibration isolator according to claim 1 , wherein said restricting surface and said overhanging outer surface are formed parallel to said vertical axis. The gap between the pair of restricting surfaces is smaller on one side in the vertical axis direction and larger on the other side in the vertical axis direction than the gap between the pair of overhanging outer surfaces when the main body is in a no-load state. The vibration isolator according to claim 1 or 2 . 7. The outer peripheral surface of the main body in an unloaded state is formed in an elliptical or elliptical shape elongated in the vertical axis direction in a cross section perpendicular to the axial center. anti-vibration device.

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