JP7263647B2 - Vehicle anti-vibration device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle anti-vibration device used when attaching the tip of a suspension arm to a vehicle body.

When the vehicle is running, the suspension arm (trailing arm) swings up and down according to the input from the road surface to the wheels. The tip of the suspension arm is attached to the vehicle body via an anti-vibration device. The vibration isolator includes an elastically deformable vibration isolator. As a result, even when the suspension arm swings, vibrations transmitted from the suspension arm to the vehicle body are suppressed by the anti-vibration device.

Patent Literature 1 discloses an example of an anti-vibration device. The anti-vibration device includes an inner cylinder member attached to the vehicle body, an outer cylinder member surrounding the inner cylinder member and attached to the tip of a suspension arm, and a vibration isolator positioned between the inner cylinder member and the outer cylinder member. (vibration isolator). The anti-vibration member is an elastic body made of rubber. When the suspension arm swings while the vehicle is running, the vibration isolating member receives torsion around the direction in which the inner tubular member extends, and translates together with the outer tubular member in a direction orthogonal to that direction. In order to suppress the vibration transmitted to the vehicle body by the anti-vibration device, it is necessary to secure deformation performance of the anti-vibration member against torsion and translation. For this reason, the anti-vibration member is formed with a gap portion (a hollow portion in Patent Document 1) penetrating in the direction in which the inner cylindrical member extends. As a result, the deformation performance of the vibration-isolating member against torsion is ensured. However, if the volume of the gap is increased, the translation of the vibration-isolating member becomes excessive, resulting in deterioration of the durability of the vibration-isolating member. Therefore, the anti-vibration member has a stopper portion (lower protrusion in Patent Document 1) that protrudes from the inner peripheral surface of the outer cylinder member toward the inner cylinder member and is in contact with the gap. When the anti-vibration member translates, the stopper portion comes into contact with the main body portion of the anti-vibration member (anti-vibration leg portion in Patent Document 1) before the gap is completely closed. As a result, deformation of the vibration-isolating member is restricted, so deterioration of the durability of the vibration-isolating member is prevented.

However, the side surface of the stopper portion of the vibration isolating member is parallel to the direction in which the inner cylindrical member extends. As a result, when the vibration-isolating member is twisted, the side surface of the stopper uniformly contacts the main body of the vibration-isolating member. That is, when the side surface of the stopper portion comes into contact with the body portion, the deformation performance of the vibration-isolating member against torsion is abruptly lowered. Therefore, the effect of suppressing vibrations transmitted from the suspension arm to the vehicle body is reduced, and there is a concern that the ride comfort will be deteriorated. In order to prevent deterioration of ride comfort, it is necessary to increase the volume of the air gap and the volume of the main body, which mainly receives torsion.

JP 2011-220435 A

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a vibration isolator for a vehicle that can more effectively ensure the deformation performance of the vibration isolator against torsion without increasing the size of the device. do.

A vibration damping device for a vehicle provided by the present invention comprises an inner cylinder having a shaft hole for attachment to a vehicle body and an outer peripheral surface along the axis of the shaft hole; an outer cylinder that has an enclosing inner peripheral surface and is fitted to the tip of the suspension arm; and an elastically deformable vibration isolator that includes a portion sandwiched between the outer peripheral surface and the inner peripheral surface, The vibration isolator includes an outer edge portion in contact with the inner peripheral surface, a body portion extending from the outer edge portion to the outer peripheral surface, and a main body portion and the outer peripheral surface that protrude from the outer edge portion toward the outer peripheral surface. The vibration isolator is surrounded by the outer edge portion, the main body portion and the stopper portion, and is surrounded by the outer edge portion, the main body portion, and the stopper portion, and from both ends in the direction in which the axial center of the shaft hole extends An open gap is formed, the stopper has a side surface facing the gap, the side surface includes an inclined portion inclined with respect to the direction in which the axis extends, and the direction in which the axis extends. In the above, the inclined portion is inclined inward from either end of the side surface toward the main body portion.

According to the vehicle vibration isolator provided by the present invention, it is possible to more effectively ensure the deformation performance of the vibration isolator against torsion without increasing the size of the device.

Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

1 is a cross-sectional view showing a state of use of a vehicle anti-vibration device according to the present invention; FIG. FIG. 2 is a plan view of the vehicle vibration isolator shown in FIG. 1 ; 3 is a cross-sectional view taken along line III-III of FIG. 2; FIG. 3 is a cross-sectional view taken along line IV-IV of FIG. 2; FIG. 3 is a cross-sectional view taken along line VV of FIG. 2; FIG. FIG. 2 is a plan view of a first modification of the vehicle vibration isolator shown in FIG. 1 ; FIG. 3 is a plan view of a second modification of the vehicle vibration isolator shown in FIG. 1 ; FIG. 8 is a plan view of a third modification of the vehicle vibration isolator shown in FIG. 1 ;

A mode for carrying out the present invention will be described with reference to the accompanying drawings.

A vehicle vibration isolator (hereinafter referred to as "vibration isolator A10") according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. Here, for convenience of explanation, fr shown in FIG. 1 indicates the vehicle front direction, rr indicates the vehicle rear direction, rh indicates the vehicle right direction, and lh indicates the vehicle left direction. FIG. 1 is a cross-sectional view along a direction perpendicular to the vertical direction of the vehicle. FIG. 2 is a diagram viewed along an axis N (details will be described later).

As shown in FIG. 1, the vibration isolator A10 is attached to both the tip portion 41 of the suspension arm 40 and the bracket 50 fixed to the vehicle body. This state of use exemplifies the case where the suspension arm 40 is one element of the rear suspension. The rear suspension is applied to the right rear wheel. The vibration isolator A10 includes an inner cylinder 10, an outer cylinder 20, and a vibration isolator 30. As shown in FIG.

As shown in FIG. 1, the inner cylinder 10 is positioned in the center of the anti-vibration device A10. The material of the inner cylinder 10 is aluminum, for example. The inner cylinder 10 has an axial hole 11 and an outer peripheral surface 101 . The shaft hole 11 is used to attach the anti-vibration device A10 to the bracket 50. As shown in FIG. The outer peripheral surface 101 extends around the axis N of the shaft hole 11 (hereinafter simply referred to as "axis N"). The outer cylinder 20 is positioned on the outer periphery of the anti-vibration device A10. The material of the outer cylinder 20 is steel, for example. The outer cylinder 20 has an inner peripheral surface 201 and a flange portion 21 . The inner peripheral surface 201 surrounds the outer peripheral surface 101 around the axis N. As shown in FIG. The flange portion 21 is positioned at one end of the outer cylinder 20 in the direction in which the axis N extends, and is formed along the inner peripheral surface 201 . The flange portion 21 protrudes from the inner peripheral surface 201 in a direction perpendicular to the direction in which the axis N extends. In the example shown by the vibration isolator A10, both the inner cylinder 10 and the outer cylinder 20 are cylindrical. Vibration isolator 30 includes a portion sandwiched between outer peripheral surface 101 and inner peripheral surface 201 and is in contact with both outer peripheral surface 101 and inner peripheral surface 201 . The vibration isolator 30 is made of an elastically deformable material. The material is, for example, natural rubber (NR). The vibration isolator 30 is vulcanized and bonded to the outer peripheral surface 101 , the inner peripheral surface 201 and the flange portion 21 .

As shown in FIG. 1, the tip portion 41 of the suspension arm 40 is formed with an opening penetrating in the direction in which the axis N extends. The anti-vibration device A10 is attached to the distal end portion 41 of the suspension arm 40 by fitting the outer cylinder 20 into the opening. At this time, the flange portion 21 contacts the tip portion 41 . Bracket 50 includes a pair of side portions 51 . The pair of side portions 51 hang downward from the vehicle body and are separated from each other in the direction in which the axis N extends. After disposing the vibration isolator A10 attached to the tip portion 41 between the pair of side portions 51, the vibration isolator A10 is attached to the vehicle body by using the fastening member 60. As shown in FIG. Fastening member 60 is composed of, for example, a bolt and a weld nut. The bolt is inserted through the shaft hole 11 . The weld nut is joined to the side portion 51 of the pair of side portions 51 that is located inward of the vehicle.

As shown in FIG. 1 , the inner cylinder 10 is fixed to the bracket 50 via the fastening member 60 when the anti-vibration device A10 is in use. The outer cylinder 20 is fixed to the tip portion 41 of the suspension arm 40 . As a result, when the suspension arm 40 swings up and down due to the input from the road surface to the rear wheels while the vehicle is running, the outer cylinder 20 rotates about the axis N relative to the inner cylinder 10 . Therefore, the vibration isolator 30 receives a twist T1 around the axis N. As shown in FIG. Furthermore, in the state of use of the vibration isolator A10 shown in FIG. 1, the axis N is inclined with respect to the left-right direction of the vehicle so that the end on the outside of the vehicle falls rearward of the vehicle. As a result, toe-out of the rear wheels is suppressed, and the running stability of the vehicle is improved. In this case, when the suspension arm 40 swings up and down, the outer cylinder 20 rotates both around the axis N and around the axis perpendicular to the axis N and passing through the center C shown in FIG. do. Therefore, the vibration isolator 30 receives both the torsion T1 and the torsion T2 about the axis perpendicular to the axis N and passing through the center C shown in FIG. Note that the torsion T obtained by synthesizing the torsion T1 and the torsion T2 exhibits a behavior of rotating around the axis Ax shown in FIG.

As shown in FIGS. 2 to 4, the vibration isolator 30 has an outer edge portion 31, a pair of body portions 32, a pair of stopper portions 33, and an annular portion .

As shown in FIGS. 2 to 4, the outer edge portion 31 is in contact with the inner peripheral surface 201 of the outer cylinder 20. As shown in FIGS. The outer edge portion 31 has a cylindrical shape along the inner peripheral surface 201 .

As shown in FIGS. 2 to 4, the pair of body portions 32 extend from the outer edge portion 31 to the outer peripheral surface 101 of the inner cylinder 10. As shown in FIGS. The pair of body portions 32 are in contact with the outer peripheral surface 101 . In the vibration isolator A10, the pair of body portions 32 are connected to each other with the inner cylinder 10 interposed therebetween. Note that the pair of main body portions 32 may be configured to be separated from each other with the inner cylinder 10 interposed therebetween. When the vibration isolator A10 is in use, the pair of main body portions 32 mainly bears the torsion that the vibration isolator 30 receives due to the swinging of the suspension arm 40 and the deformation that accompanies the translation of the vibration isolator 30 .

As shown in FIGS. 2 and 4 , the pair of stopper portions 33 protrude from the outer edge portion 31 toward the outer peripheral surface 101 of the inner cylinder 10 . The pair of stopper portions 33 are separated from both the pair of main body portions 32 and the outer peripheral surface 101 of the inner cylinder 10 . In addition, the pair of stopper portions 33 are separated from each other in a direction perpendicular to the direction in which the axis N extends. Each of the pair of stopper portions 33 has a pair of main surfaces 331 and side surfaces 332 . The pair of main surfaces 331 are located at both ends of the stopper portion 33 in the direction in which the axis N extends, and face opposite sides. In the vibration isolator A10, each of the pair of main surfaces 331 is triangular. The side surface 332 is located between the pair of major surfaces 331 . The side surfaces 332 are connected to the pair of main surfaces 331 .

As shown in FIGS. 2 to 4, the annular portion 34 is positioned at one end of the vibration isolator 30 in the direction in which the axis N extends. The annular portion 34 is formed along a surface that is in contact with the flange portion 21 of the outer cylinder 20 and faces the direction in which the axis N of the flange portion 21 extends. The annular portion 34 is connected to the outer edge portion 31 . As shown in FIG. 2 , the annular portion 34 overlaps the outer edge portion 31 when viewed along the direction in which the axis N extends.

As shown in FIGS. 2, 4 and 5, the vibration isolator 30 has a pair of gaps 35 formed therein. Each of the pair of gaps 35 is surrounded by one of the outer edge portion 31 , the pair of body portions 32 , and the pair of stopper portions 33 . The pair of gap portions 35 are separated from each other in the same direction as the direction in which the pair of stopper portions 33 are separated from each other. The pair of gaps 35 are open from both ends of the vibration isolator 30 in the direction in which the axis N extends. In the vibration isolator A10, the pair of gaps 35 penetrates the vibration isolator 30 in the direction in which the axis N extends. The pair of gaps 35 are closed by a portion of the vibration isolator 30 different from the pair of main body portions 32 and the pair of stopper portions 33 in the vicinity of the center of the vibration isolator 30 in the direction in which the axis N extends. configuration may be used. Each of the side surfaces 332 of the pair of stopper portions 33 faces one of the pair of gap portions 35 . As shown in FIG. 2 , each of the pair of gaps 35 includes a straight region 351 and a pair of oblique regions 352 . When viewed along the direction in which the axis N extends, the orthogonal region 351 extends in a direction orthogonal to both the direction in which the axis N extends and the direction in which the pair of gaps 35 separate from each other. The pair of oblique regions 352 extend from both ends of the straight regions 351 toward the inner peripheral surface 201 of the outer cylinder 20 when viewed along the direction in which the axis N extends. In addition, each of the pair of oblique regions 352 is inclined with respect to the straight region 351 when viewed along the direction in which the axis N extends.

As shown in FIG. 5, each of the side surfaces 332 of the pair of stopper portions 33 includes a parallel portion 332A and a pair of inclined portions 332B. The parallel portion 332A is parallel to the direction in which the axis N extends. Each of the pair of inclined portions 332B is connected to either the parallel portion 332A or the pair of main surfaces 331. As shown in FIG. The pair of inclined portions 332B are located on both sides of the side surface 332 in the direction in which the axis N extends. Each of the pair of inclined portions 332B is inclined with respect to the direction in which the axis N extends. In the direction in which the axis N extends, each of the pair of inclined portions 332B is inclined inward from either end of the side surface 332 toward the pair of main body portions 32 . In the anti-vibration device A10, both of the pair of inclined portions 332B are flat. In this case, the magnitude of the inclination angle α of each of the pair of inclined portions 332B with respect to the parallel portion 332A shown in FIG. 5 is 10° or more and 20° or less. The pair of inclined portions 332</b>B may be curved surfaces that protrude toward the pair of main body portions 32 .

In FIG. 2, the pair of inclined portions 332B are indicated by a region consisting of a plurality of points. As shown in FIG. 2, in the vibration isolator A10, each of the pair of inclined portions 332B is divided into two regions sandwiching the end point 331A of the main surface 331. As shown in FIG. These two regions are connected to each other on one side of the side surface 332 passing through the end point 331A. 331 A of end points refer to the point located nearest with respect to the outer peripheral surface 101 of the inner cylinder 10 in the edge|side which comprises a part of main surface 331 and a pair of inclination parts 332B are connected.

Next, a vibration isolator A11, which is a first modification of the vibration isolator A10, will be described with reference to FIG. The vibration isolator A11 differs from the previously described vibration isolator A10 in the configuration of the pair of stopper portions 33 of the vibration isolator 30 . As shown in FIG. 6, in each of the pair of stopper portions 33, each of the pair of main surfaces 331 is semicircular. On each of the side surfaces 332 of the pair of stopper portions 33, the area of each of the pair of inclined portions 332B of the anti-vibration device A11 is smaller than the area of each of the pair of inclined portions 332B of the anti-vibration device A10.

Next, a vibration isolator A12, which is a second modification of the vibration isolator A10, will be described with reference to FIG. The vibration isolator A12 differs from the previously described vibration isolator A10 in the configuration of the pair of stopper portions 33 of the vibration isolator 30 . As shown in FIG. 7 , in each of the pair of stopper portions 33 , each of the pair of main surfaces 331 has a trapezoidal shape with a lower base connected to the outer edge portion 31 . Accordingly, in the vibration isolator A12, a pair of end points 331A are present at both ends of the upper base of each of the pair of main surfaces 331. As shown in FIG. In each of the side surfaces 332 of the pair of stopper portions 33 , the parallel portion 332A is connected to the upper base of each of the pair of main surfaces 331 . In addition, the area of each of the pair of inclined portions 332B of the anti-vibration device A12 is smaller than the area of each of the pair of inclined portions 332B of the anti-vibration device A10. Also, in each of the pair of inclined portions 332B, two regions sandwiching the pair of end points 331A of the main surface 331 are separated from each other when viewed along the direction in which the axis N extends.

Next, a vibration isolator A13, which is a third modification of the vibration isolator A10, will be described with reference to FIG. The vibration isolator A13 differs from the previously described vibration isolator A10 in the configuration of the pair of stopper portions 33 of the vibration isolator 30 . As shown in FIG. 8 , in each of the pair of stopper portions 33 , each of the pair of main surfaces 331 has a trapezoidal shape with a lower base connected to the outer edge portion 31 . Accordingly, in the vibration isolator A13, a pair of end points 331A are present at both ends of the upper base of each of the pair of main surfaces 331. As shown in FIG. In each of the side surfaces 332 of the pair of stopper portions 33 , the pair of inclined portions 332B includes a region facing one of the straight regions 351 of the pair of gap portions 35 when viewed along the axis N. As a result, each of the pair of inclined portions 332B forms an integral region, unlike the case of the vibration isolator A10 to the vibration isolator A12. In addition, in the vibration isolator A13, the pair of main body portions 32 is configured to cover the entire outer peripheral surface 101 of the inner cylinder 10. As shown in FIG.

Next, the effects of the anti-vibration device A10 will be described.

The vibration isolator A10 includes an elastically deformable vibration isolator 30 including a portion sandwiched between the outer peripheral surface 101 of the inner cylinder 10 and the inner peripheral surface 201 of the outer cylinder 20 . The vibration isolator 30 has an outer edge portion 31 , a body portion 32 and a stopper portion 33 . Further, the vibration isolator 30 is surrounded by the outer edge portion 31, the main body portion 32 and the stopper portion 33, and has a gap portion 35 opened from both ends in the direction in which the axis N extends. The stopper portion 33 has a side surface 332 facing the gap portion 35 . The side surface 332 includes an inclined portion 332B inclined with respect to the direction in which the axis N extends. In the direction in which the axis N extends, the inclined portion 332B is inclined inward from either end of the side surface 332 toward the main body portion 32 . As a result, when the vibration isolator A10 shown in FIG. 1 is used, when the vibration isolator 30 receives a twist (twist T1) about the axis N, the gap 35 is gradually closed, and the side surface 332 of the stopper 33 is deformed. It comes into contact with the body portion 32 . However, it is the parallel portion 332A of the side surface 332 that first contacts the body portion 32, and the inclined portion 332B does not. Therefore, in the region of the body portion 32 facing the inclined portion 332B, both performances of deformation performance against translation and deformation performance against torsion of the vibration isolator 30 in the direction orthogonal to the axis N are ensured. remain. Therefore, even if the side surface 332 of the stopper portion 33 comes into contact with the main body portion 32, the deterioration of the deformation performance of the vibration isolator 30 against torsion becomes more gradual. Therefore, according to the vibration isolator A10, it is possible to more effectively ensure the deformation performance of the vibration isolator 30 against torsion without increasing the size of the vibration isolator A10.

In the state of use of the vibration isolator A10 shown in FIG. 1, the vibration isolator 30 is twisted (torsion T1) around the axis N, perpendicular to the axis N, and center C shown in FIG. It also receives torsion (torsion T2) around the axis passing through. Therefore, when the vibration isolator 30 is subjected to a combined twist (torsion T) of both of these, the regions of the side surfaces 332 of the stopper portion 33 located at both ends in the direction in which the axis N extends are first twisted into the main body portion 32 . try to contact When this area contacts the body portion 32, the stopper portion 33 restricts the deformation of the body portion 32 to a greater extent, so tensile stress concentrates around the area of the body portion 32 that the stopper portion 33 contacts. As a result, there is a concern that the durability of the vibration isolator 30 will be lowered. Therefore, by making the region the inclined portion 332B, even if the vibration isolator 30 receives both of these torsions, the region is prevented from coming into contact with the main body portion 32 first. Therefore, it is possible to prevent deterioration in the durability of the vibration isolator 30 due to concentration of tensile stress.

By forming the inclined portion 332B of the side surface 332 of the stopper portion 33 into a curved surface that protrudes toward the main body portion 32, the deformation performance of the vibration isolator 30 against torsion is improved as compared with the case where the inclined portion 332B is flat. The decline becomes more gradual.

The use state of the vibration isolator A10 shown in FIG. 1 shows the case where the tip portion 41 of the suspension arm 40, which applies the vibration isolator A10 to the right rear wheel, is attached. It can also be applied when attached to the tip portion 41 of the suspension arm 40 .

The invention is not limited to the embodiments described above. The specific configuration of each part of the present invention can be changed in various ways.

A10, A11, A12, A13: vibration isolator 10: inner cylinder 101: outer peripheral surface 11: shaft hole 20: outer cylinder 201: inner peripheral surface 21: flange portion 30: vibration isolator 31: outer edge portion 32: body portion 33 : Stopper portion 331 : Main surface 331A : End point 332 : Side surface 332A : Parallel portion 332B : Inclined portion 34 : Annular portion 35 : Gap portion 351 : Straight area 352 : Inclined area 40 : Suspension arm 41 : Tip 50 : Bracket 51 : Side 60: Fastening member N: Axial center C: Center Ax: Axis α: Tilt angle

Claims (1)

an inner cylinder having a shaft hole for attachment to a vehicle body and an outer peripheral surface along the axis of the shaft hole;
an outer cylinder that has an inner peripheral surface that surrounds the outer peripheral surface around the axis and is fitted to a tip portion of a suspension arm;
a vibration isolator that includes a portion sandwiched between the outer peripheral surface and the inner peripheral surface and is elastically deformable;
The vibration isolator includes an outer edge portion in contact with the inner peripheral surface, a body portion extending from the outer edge portion to the outer peripheral surface, and a main body portion and the outer peripheral surface that protrude from the outer edge portion toward the outer peripheral surface. and a stopper portion spaced apart from both of the
The vibration isolator is surrounded by the outer edge portion, the main body portion, and the stopper portion, and is formed with a gap opening from both sides in the axial direction, which is the direction in which the axial center of the shaft hole extends. cage ,
The stopper portion has a pair of main surfaces facing opposite to each other in the axial direction, and a pair of side surfaces facing the gap and having both sides in the axial direction connected to the pair of main surfaces . has
Each of the pair of main surfaces includes an end point located closest to the outer peripheral surface,
the stopper portion has an edge connecting the end points of the pair of main surfaces and extending along the axial direction;
The pair of side surfaces are connected to each other with the edge as a boundary around the axis,
Each of the pair of side surfaces includes a pair of inclined portions individually connected to the pair of main surfaces, and parallel portions extending along the axial direction and connected to the pair of inclined portions on both sides in the axial direction. , including
A vibration isolator for a vehicle, wherein each of the pair of inclined portions is inclined with respect to the axial direction from either one of the pair of main surfaces toward the outer peripheral surface.

Images