JP2024118179A - Vehicle suspension arm mounting structure - Google Patents

Abstract

To provide a mounting structure of a suspension arm for a vehicle, which can prevent excessive input of an elastic bush and realize desired running stability.SOLUTION: A mounting structure of a suspension arm for a vehicle comprises: a cylindrical bracket 20 fixed to a vehicle body 1, having a center axis in a vehicle body longitudinal direction; a rear side bush 18 having a center axis in the vehicle body longitudinal direction, held on an inner periphery of the bracket; a rear arm part 10 in which a rod-like rear end 10a extending to the rear of the vehicle body is held on an inner periphery of an elastic bush; and a stopper 24 fixed to the rear end of the rear arm part at the front of the vehicle body from the elastic bush and on the inner peripheral side of the bracket. The vehicle body rear end of the stopper is located at the rear of the vehicle body from the vehicle body front end of the bracket, and when the rear end of the rear arm part is displaced by a predetermined distance in a vehicle width direction, the stopper is brought into contact with the inner periphery of the bracket.SELECTED DRAWING: Figure 3

Description

Application for application of Article 30, Paragraph 2 of the Patent Act filed September 15, 2022 Disclosure due to product (vehicle) sales in countries around the world

The present invention relates to a mounting structure for a vehicle suspension arm.

Conventionally, in vehicle suspensions, an elastic bush with increased compliance is provided at the connection point of the suspension arm to the vehicle body, thereby improving the damping of vibrations transmitted from the suspension arm to the vehicle body while the vehicle is moving, and achieving good NVH performance. For example, in the suspension arm support structure described in Patent Document 1, a journal portion extending toward the rear of the vehicle body is provided at the rear end of the lower arm that constitutes the suspension on the vehicle body side, and this journal portion is inserted into the inner cylinder of a cylindrical rubber bush, and the outer cylinder of the rubber bush is fixed to a bracket on the vehicle body side. In this way, the lower arm is connected to the vehicle body.

Japanese Patent Application Publication No. 10-309917

On the other hand, to improve driving stability, it is desirable to suppress the compliance of the elastic bushing so that the suspension alignment does not change excessively. However, if the compliance of the elastic bushing is reduced, the elastic bushing becomes hard, and there is a possibility that the elastic bushing may crack if a large input is applied from the suspension arm, for example when going over a bump while driving at high speed. In addition, in order to achieve both reduced compliance and improved durability, it is possible to increase the diameter of the elastic bushing, but this would increase the cost of the elastic bushing and increase the size of the vehicle side subframe for mounting the elastic bushing.

The present invention was made to solve the problems of the conventional technology described above, and aims to provide a mounting structure for a vehicle suspension arm that prevents excessive input to the elastic bushing and achieves the desired driving stability.

In order to achieve the above object, the mounting structure of the suspension arm for a vehicle of the present invention comprises a cylindrical bracket fixed to the vehicle body and having a central axis in the longitudinal direction of the vehicle body, a cylindrical elastic bush having a central axis in the longitudinal direction of the vehicle body, the outer periphery of the elastic bush being held by the inner periphery of the bracket, an arm that can swing in the vertical direction of the vehicle body about an axis that passes through the elastic bush and extends in the longitudinal direction of the vehicle body, the arm being connected to the bracket via the elastic bush by having its rod-shaped rear end extending rearward of the vehicle body held by the inner periphery of the elastic bush, and a stopper that is fixed to the rear end of the arm forward of the elastic bush and on the inner periphery side of the bracket, the rear end of the stopper being located rearward of the vehicle body from the front end of the bracket, and when the rear end of the arm is displaced a predetermined distance in the vehicle width direction, the stopper comes into contact with the inner periphery of the bracket.

In the present invention configured in this way, when there is an input that moves the rear end of the arm in the vehicle width direction, if the rear end of the arm displaces a predetermined distance in the vehicle width direction, the stopper comes into contact with the inner circumference of the bracket, suppressing further movement of the rear end of the arm. Therefore, by suppressing the compliance of the elastic bushing, it is possible to prevent excessive input to the elastic bushing while achieving the desired driving stability.

In the present invention, the stopper preferably has a core member fixed to the rear end of the arm forward of the elastic bushing, and a first elastic member provided on the outer surface of the core member that faces the inner circumference of the bracket.

In the present invention configured in this way, the first elastic member is interposed between the core member of the stopper and the inner circumference of the bracket, so that the reaction force generated in response to the elastic deformation of the first elastic member can prevent sudden changes in handling stability and prevent excessive input to the elastic bushing. It can also prevent abnormal noise caused by contact between the core member and the bracket.

In the present invention, the rear end of the arm preferably has a protrusion that protrudes inward in the vehicle width direction further forward than the vehicle width inner end of the bracket's inner periphery, and when the rear end of the arm is displaced a predetermined distance or more toward the rear of the vehicle, the rear end of the protrusion presses against the vehicle body front end of the bracket.

In the present invention configured in this way, when there is an input that moves the rear end of the arm toward the rear of the vehicle, if the rear end of the arm is displaced toward the rear of the vehicle by more than a predetermined distance, the rear end of the protrusion presses against the front end of the bracket, preventing further movement of the rear end of the arm. Therefore, by suppressing the compliance of the elastic bushing, it is possible to prevent excessive input to the elastic bushing while achieving the desired driving stability.

The present invention also preferably includes a second elastic member provided between the rear end of the protrusion and the front end of the bracket.

In the present invention configured in this way, the second elastic member is interposed between the rear end of the protrusion on the vehicle body and the front end of the bracket on the vehicle body, so that the reaction force generated in response to the elastic deformation of the second elastic member can prevent sudden changes in handling stability and prevent excessive input to the elastic bushing. It can also prevent abnormal noise caused by contact between the protrusion and the bracket.

In the present invention, the stopper has a core member that is fixed to the rear end of the arm forward of the elastic bushing, and a first elastic member that is provided on the outer surface of the core member that faces the inner circumference of the bracket, and the first elastic member and the second elastic member are integrally formed.

In the present invention configured in this manner, the first elastic member is interposed between the core member of the stopper and the inner circumference of the bracket, so that the reaction force generated in response to the elastic deformation of the first elastic member can prevent abrupt changes in handling stability and prevent excessive input to the elastic bushing. It can also prevent abnormal noise caused by contact between the core member and the bracket. Furthermore, since the first elastic member and the second elastic member are integrally formed, the manufacturing process of the stopper can be simplified.

The mounting structure for a vehicle suspension arm according to the present invention can prevent excessive input to the elastic bushing and achieve the desired driving stability.

1 is a perspective view showing a mounting structure for a vehicle suspension arm according to an embodiment of the present invention; 1 is a plan view of a right front wheel side of a vehicle suspension arm mounting structure according to an embodiment of the present invention, viewed from above the vehicle body. 4 is a cross-sectional view showing a rear end portion of a rear arm portion of a lower arm, a rear bush, a stopper, and a bracket as viewed from above a vehicle body according to an embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 2. FIG. 2 is a perspective view showing a stopper according to an embodiment of the present invention. 1 is a cross-sectional view seen from above the vehicle body to explain the force and displacement applied to the rear end portion, rear bush, and stopper of the rear arm portion of the lower arm on the right front wheel side when a force is applied to the right front wheel toward the rear of the vehicle body. FIG. 1 is a cross-sectional view seen from above the vehicle body to explain the force and displacement applied to the rear end portion, rear bush, and stopper of the rear arm portion of the lower arm on the right front wheel side when a force is applied to the right front wheel toward the rear of the vehicle body. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 6.

The following describes a vehicle suspension arm mounting structure according to an embodiment of the present invention with reference to the attached drawings.

First, the overall configuration of the mounting structure for a vehicle suspension arm according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a perspective view showing the mounting structure for a vehicle suspension arm according to this embodiment. Figure 2 is a plan view of the right front wheel side of the mounting structure for a vehicle suspension arm according to this embodiment, viewed from above the vehicle body. Note that the vehicle suspension arm shown in Figure 1 etc. is disposed on the right front wheel side of the vehicle, and the "front", "upper", "inner", and "outer" indicated by the arrows indicate the front of the vehicle body, the upper part of the vehicle body, the inner side in the vehicle width direction, and the outer side in the vehicle width direction, respectively.

The mounting structure of the vehicle suspension arm of this embodiment shown in Figure 1 is a structure in which a lower arm 6 of a double wishbone type front suspension 4 that connects the vehicle body 1 and the wheels 2 is mounted to the vehicle body 1. As shown in Figure 1, the lower arm 6 is an A-shaped arm having a front arm portion 8 that extends almost in the vehicle width direction, and a rear arm portion 10 that extends diagonally forward from the inside to the outside in the vehicle width direction. The inner end of the front arm portion 8 in the vehicle width direction and the rod-shaped rear end portion 10a of the rear arm portion 10 that extends toward the rear of the vehicle body are attached to the vehicle body 1 at two mounting portions 12, 14 at the front and rear, respectively, and the lower arm 6 is able to swing in the vertical direction of the vehicle body around an axis that passes through these mounting portions 12, 14 and extends in the fore-and-aft direction of the vehicle body.

The inner end of the front arm 8 in the vehicle width direction is attached to the vehicle body 1 at the front mounting part 12 via a cylindrical front bush 16. The rear end 10a of the rear arm 10 is attached to the vehicle body 1 at the rear mounting part 14 via a cylindrical rear bush 18. The rear bush 18 is held by a cylindrical bracket 20 fixed to the vehicle body 1. The rear end 10a of the rear arm 10 is provided with a protrusion 22 that protrudes inward in the vehicle width direction, forward of the vehicle body front end of the bracket 20.

The front bush 16 and the rear bush 18 are arranged so that they have a central axis in the fore-and-aft direction of the vehicle body. The compliance of each of these bushes arranged in the lower arm 6 is set so as to obtain an appropriate balance between the desired handling stability and NVH performance. In order to ensure handling stability, the front bush 16 has a relatively smaller compliance than the rear bush 18.

A stopper 24 is provided on the vehicle body front side of the rear bush 18 and on the inner periphery side of the bracket 20, and is fixed to the rear end portion 10a of the rear arm portion 10.

Next, the configuration of the mounting structure for a vehicle suspension arm according to this embodiment will be specifically described with reference to Figures 3 to 5. Figure 3 is a cross-sectional view of the rear end 10a of the rear arm portion 10 of the lower arm 6, the rear bush 18, the stopper 24, and the bracket 20 according to this embodiment, as viewed from above the vehicle body, Figure 4 is a cross-sectional view taken along line IV-IV in Figure 2, and Figure 5 is a perspective view showing the stopper 24 according to this embodiment.

The bracket 20 is formed in a thin-walled cylindrical shape with a central axis in the fore-and-aft direction of the vehicle body, and a flange portion 20a that extends radially outward is provided at the front end of the vehicle body. This bracket 20 is fixed to the outside of the vehicle body 1 in the vehicle width direction by welding, bolting, etc.

The rear bushing 18 is a cylindrical elastic bushing, and has a cylindrical outer tube 26, an inner tube 28 that has a smaller diameter than the outer tube 26 and is disposed on the inner periphery of the outer tube 26, and a cylindrical elastic body 30 that is disposed between the outer tube 26 and the inner tube 28. The outer tube 26, the inner tube 28, and the elastic body 30 are fixed to each other with an adhesive.

The outer tube 26 and the inner tube 28 are formed from metal plates such as steel plates. The elastic body 30 is made of rubber, for example, and is formed to have the radial thickness and axial length required to achieve spring characteristics and damping characteristics according to the expected load input. As shown in FIG. 3, recesses can be formed at both axial ends of the elastic body 30 according to the desired characteristics, and restricting members can be embedded inside the elastic body 30 to restrict the amount of deformation of the elastic body 30.

The rear bush 18 configured as described above is pressed into the inner circumference of the bracket 20 along the central axis of the bracket 20 from the rear side of the vehicle body, and is held by the inner circumference of the bracket 20. As shown in FIG. 3, the entire rear bush 18 does not have to be pressed into the bracket 20, but the part of the rear bush 18 that receives the load (the axial center part of the elastic body 30 in the example of FIG. 3) is located inside the bracket 20.

The rear end 10a of the rear arm portion 10 is formed in a round bar shape extending toward the rear of the vehicle body. A protrusion 22 that protrudes inward in the vehicle width direction is provided on the front side of the rear end 10a. The length of the protrusion 22 in the vehicle width direction is set so that when an input is applied to the suspension arm from the wheel 2 and the rear end 10a of the rear arm portion 10 moves inward in the vehicle width direction to its maximum extent, the inner end of the protrusion 22 in the vehicle width direction does not interfere with the vehicle body 1, and the protrusion 22 overlaps with the inner part of the flange portion 20a of the bracket 20 in the vehicle width direction when viewed from the front-rear direction of the vehicle body.

The stopper 24 is fitted and fixed to the rear end 10a of the rear arm portion 10 so as to be adjacent to the rear side of the vehicle body of the protruding portion 22 of the rear arm portion 10. Furthermore, the rear end 10a on the vehicle body rear side of the stopper 24 is pressed into the inner circumference of the inner tube 28 of the rear bush 18 from the front side of the vehicle body and is held by the inner circumference of the inner tube 28. As shown in FIG. 3, the rear end 10a of the rear arm portion 10 does not have to be pressed into the entire rear bush 18, but the rear end 10a of the rear arm portion 10 is pressed into the inner tube 28 of the rear bush 18 to a position where the rear end 10a of the rear arm portion 10 and the load-bearing portion of the rear bush 18 overlap.

The stopper 24 prevents excessive deformation of the rear bush 18 by restricting the movement of the rear end 10a of the rear arm 10 in the vehicle width direction, and is fixed to the rear end 10a of the rear arm 10, forward of the rear bush 18 and on the inner periphery of the bracket 20, so that the rear end of the stopper 24 is located rearward of the front end of the bracket 20.

The stopper 24 has a core member 32 that has a shape of a cylinder with a central axis in the fore-and-aft direction of the vehicle body with the upper and lower sides of the vehicle body cut off, and an elastic member 34 that is provided on the outer periphery of the core member 32 (i.e., the surface of the outer surface of the core member 32 that faces the inner periphery of the bracket 20).

The core member 32 is formed using a metal such as an aluminum alloy. The rear end 10a of the rear arm portion 10 is press-fitted into the inner circumference of the core member 32, thereby fixing the stopper 24 to the rear end 10a of the rear arm portion 10. The inner and outer parts of the outer circumference of the core member 32 in the vehicle width direction are formed to have curved surfaces that follow the inner circumference of the bracket 20. Note that the core member 32 shown in FIG. 3 etc. is solid except for the central hole into which the rear end 10a of the rear arm portion 10 is inserted, but appropriate hollows may be formed to reduce weight while ensuring the necessary strength.

The elastic member 34 is formed, for example, from rubber, and has an outer peripheral portion 34a that covers the outer periphery of the core member 32, and an end surface portion 34b that extends from the end of the outer peripheral portion 34a that is forward and inward in the vehicle width direction along the front end surface of the core member 32 and protrudes inward in the vehicle width direction beyond the outer peripheral portion 34a of the elastic member 34. In particular, the inner end portion in the vehicle width direction of the end surface portion 34b protrudes inward in the vehicle width direction to the same position as the inner end portion in the vehicle width direction of the protruding portion 22 of the rear arm portion 10. The outer peripheral portion 34a and the end surface portion 34b are formed integrally, and the outer peripheral portion 34a is bonded to the outer periphery of the core member 32, and the end surface portion 34b is bonded to the front end surface of the core member 32.

The thickness of the outer peripheral portion 34a of the elastic member 34 on the inside and outside in the vehicle width direction is set so as to have the desired reaction force characteristics when the suspension arm receives an input from the wheel 2 and the rear end portion 10a of the rear arm portion 10 moves in the vehicle width direction, causing the outer peripheral portion 34a of the elastic member 34 to be pressed against the inner circumference of the bracket 20, and the thickness on the inside in the vehicle width direction is greater than the thickness on the outside in the vehicle width direction.

The radius of curvature of the outer periphery 34a of the elastic member 34 is smaller than the radius of curvature of the inner periphery of the bracket 20. As a result, when the suspension arm receives an input from the wheel 2 and the rear end 10a of the rear arm section 10 moves in the vehicle width direction, pressing the outer periphery 34a of the elastic member 34 against the inner periphery of the bracket 20, the contact area between the outer periphery 34a of the elastic member 34 and the inner periphery of the bracket 20 gradually increases, and the reaction force generated by the elastic deformation of the outer periphery 34a of the elastic member 34 gradually increases.

The thickness of the end surface portion 34b of the elastic member 34 is set so as to have the desired reaction force characteristics when the front end surface of the end surface portion 34b contacts the rear end surface of the protruding portion 22 of the rear arm portion 10 when the stopper 24 is fixed to the rear end portion 10a of the rear arm portion 10, and when an input is applied from the wheel 2 to the suspension arm, the rear end portion 10a of the rear arm portion 10 moves rearward, causing the end surface portion 34b of the elastic member 34 to be sandwiched between the rear end surface of the protruding portion 22 of the rear arm portion 10 and the front end surface of the bracket 20.

Next, the operation of the mounting structure for a vehicle suspension arm according to this embodiment will be described with reference to Figures 6 to 8. Figure 6 is a cross-sectional view seen from above the vehicle body to explain the force and displacement applied to the rear end 10a of the rear arm portion 10 of the lower arm 6 on the right front wheel side, the rear bush 18, and the stopper 24 when a force is applied to the right front wheel toward the rear of the vehicle body. Figure 7 is a cross-sectional view seen from above the vehicle body to explain the force and displacement applied to the rear end 10a of the rear arm portion 10 of the lower arm 6 on the right front wheel side, the rear bush 18, and the stopper 24 when a force stronger than that in the example of Figure 6 is applied to the right front wheel toward the rear of the vehicle body. Figure 8 is a cross-sectional view taken along line VIII-VIII in Figure 6.

When a force is applied to the right wheel 2 toward the rear of the vehicle body by going over a step on the road while the vehicle is traveling, and this force is transmitted to the lower arm 6 on the right front wheel side, a moment is generated that rotates the lower arm 6 rearward around the front mounting part 12 as an axis. As a result, as shown by the white arrow in FIG. 6, a force is generated that moves the rear end 10a of the rear arm part 10 inward in the vehicle width direction. When this force is transmitted from the rear end 10a of the rear arm part 10 to the rear bush 18, the rear end 10a of the rear arm part 10 moves inward in the vehicle width direction, and the inner part of the elastic body 30 of the rear bush 18 in the vehicle width direction is compressed and the outer part of the elastic body 30 in the vehicle width direction is stretched. The reaction force generated in response to the elastic deformation of the elastic body 30 at this time gradually suppresses the movement of the rear end 10a of the rear arm part 10, i.e., the rotation of the lower arm 6, so that a sudden change in handling stability can be prevented.

When the deformation of the elastic body 30 becomes large and the rear end 10a of the rear arm portion 10 moves further inward in the vehicle width direction, the outer peripheral portion 34a of the elastic member 34 of the stopper 24 comes into contact with the inner periphery of the bracket 20. When the rear end 10a of the rear arm portion 10 moves further inward in the vehicle width direction, the outer peripheral portion 34a of the elastic member 34 of the stopper 24 is compressed between the inner periphery of the bracket 20 and the outer periphery of the core member 32. The reaction force generated in response to the elastic deformation of the outer peripheral portion 34a of the elastic member 34 at this time further suppresses the movement of the rear end 10a of the rear arm portion 10, i.e., the rotation of the lower arm 6, thereby preventing a sudden change in handling stability and preventing excessive deformation of the elastic body 30 of the rear bush 18. In addition, since the elastic member 34 is interposed between the core member 32 of the stopper 24 and the bracket 20, the generation of abnormal noise due to contact between the core member 32 and the bracket 20 can also be prevented.

In addition, when a relatively large force is applied to the right wheel 2 toward the rear of the vehicle body due to going over a bump in the road while the vehicle is traveling at high speed, and this force is transmitted to the lower arm 6 on the right front wheel side, a force is generated that moves the entire lower arm 6 toward the rear of the vehicle body in addition to a moment that rotates the lower arm 6 rearward about the front mounting part 12 as an axis. As a result, as shown by the white arrow in Figure 7, a force is generated that moves the rear end part 10a of the rear arm part 10 inward in the vehicle width direction and toward the rear of the vehicle body. When this force is transmitted from the rear end part 10a of the rear arm part 10 to the rear bush 18, the rear end part 10a of the rear arm part 10 moves inward in the vehicle width direction and toward the rear of the vehicle body, and the inner part in the vehicle width direction of the elastic body 30 of the rear bush 18 is compressed and the outer part in the vehicle width direction is stretched, and further the inner tube 28 side of the elastic body 30 protrudes toward the rear of the vehicle body more than the outer tube 26 side. The reaction force generated in response to the elastic deformation of the elastic body 30 at this time gradually suppresses the movement of the rear end 10a of the rear arm portion 10, i.e., the rotation of the lower arm 6 and the movement toward the rear of the vehicle body, thereby preventing a sudden change in handling stability.

When the deformation of the elastic body 30 becomes large and the rear end 10a of the rear arm section 10 moves further inward in the vehicle width direction and toward the rear of the vehicle, the outer peripheral portion 34a of the elastic member 34 of the stopper 24 comes into contact with the inner peripheral portion of the bracket 20, and the rear end face of the end face portion 34b of the elastic member 34 comes into contact with the front end face of the bracket 20. When the rear end 10a of the rear arm section 10 moves further inward in the vehicle width direction and toward the rear of the vehicle, the end face portion 34b of the elastic member 34 of the stopper 24 is compressed between the rear end face of the protruding portion 22 of the rear arm section 10 and the front end face of the bracket 20. The reaction force generated in response to the elastic deformation of the outer peripheral portion 34a and the end surface portion 34b of the elastic member 34 at this time further suppresses the movement of the rear end portion 10a of the rear arm portion 10, i.e., the rotation of the lower arm 6 and the movement toward the rear of the vehicle body, thereby preventing a sudden change in handling stability and preventing excessive deformation of the elastic body 30 of the rear bush 18. In addition, since the elastic member 34 is interposed between the core member 32 of the stopper 24 and the protrusion 22 of the rear arm portion 10 and the bracket 20, the generation of abnormal noise due to contact between the core member 32 and the protrusion 22 and the bracket 20 can also be prevented.

In addition, the inner and outer parts of the outer periphery of the stopper 24 in the vehicle width direction are formed to have curved surfaces that follow the inner periphery of the bracket 20. Therefore, even if the stopper 24 rotates around an axis in the fore-aft direction of the vehicle body as shown in FIG. 8 in response to the swinging of the lower arm 6 in the vertical direction of the vehicle body, the same reaction force characteristics are obtained when the outer periphery part 34a of the elastic member 34 of the stopper 24 is pressed against the inner periphery of the bracket 20.

Next, a further modification of the embodiment of the present invention will be described.
First, in the above-described embodiment, a structure in which the lower arm 6 of the double wishbone type front suspension 4 is attached to the vehicle body 1 has been described as an example, but the present invention can also be applied to an upper arm or double wishbone type rear suspension, or other types of suspension (e.g., multi-link type, semi-trailing arm type, strut type, etc.).

In the above embodiment, the outer peripheral portion 34a and the end surface portion 34b of the elastic member 34 of the stopper 24 are described as being integrally formed, but the outer peripheral portion 34a and the end surface portion 34b may be formed as separate members.

In addition, in the above-described embodiment, the protrusion 22 is provided on the rear end 10a of the rear arm portion 10, but if the movement of the rear end 10a of the rear arm portion 10 toward the rear of the vehicle body can be restricted by other means and excessive deformation of the rear bush 18 can be suppressed, the protrusion 22 may be omitted.

Next, we will explain the effects of the mounting structure for a vehicle suspension arm according to the above-mentioned embodiment of the present invention and the modified embodiment of the present invention.

First, the mounting structure of the vehicle suspension arm includes a stopper 24 fixed to the rear end 10a of the rear arm portion 10, forward of the rear bush 18 and on the inner periphery of the bracket 20. The rear end of the stopper 24 is located rearward of the front end of the bracket 20, and when the rear end 10a of the rear arm portion 10 is displaced a predetermined distance in the vehicle width direction, the stopper 24 comes into contact with the inner periphery of the bracket 20. Therefore, when there is an input to move the rear end 10a of the rear arm portion 10 in the vehicle width direction, when the rear end 10a of the rear arm portion 10 is displaced a predetermined distance in the vehicle width direction, the stopper 24 comes into contact with the inner periphery of the bracket 20, so that further movement of the rear end 10a of the rear arm portion 10 is suppressed. Therefore, by suppressing the compliance of the rear bush 18, it is possible to prevent excessive input to the rear bush 18 while realizing the desired driving stability.

In addition, since the outer peripheral portion 34a of the elastic member 34 is interposed between the core member 32 of the stopper 24 and the inner periphery of the bracket 20, the reaction force generated in response to the elastic deformation of the outer peripheral portion 34a of the elastic member 34 prevents abrupt changes in handling stability and prevents excessive input to the rear bush 18. It also prevents abnormal noise caused by contact between the core member 32 and the bracket 20.

In addition, when there is an input that moves the rear end 10a of the rear arm portion 10 toward the rear of the vehicle, if the rear end 10a of the rear arm portion 10 is displaced toward the rear of the vehicle by more than a predetermined distance, the rear end of the protrusion 22 presses against the front end of the bracket 20, thereby preventing further movement of the rear end 10a of the rear arm portion 10. Therefore, by suppressing the compliance of the rear bush 18, it is possible to prevent excessive input to the rear bush 18 while achieving the desired driving stability.

In addition, since the end surface portion 34b of the elastic member 34 is interposed between the rear end of the protrusion 22 and the front end of the bracket 20, the reaction force generated in response to the elastic deformation of the end surface portion 34b of the elastic member 34 prevents abrupt changes in handling stability and prevents excessive input to the rear bush 18. It also prevents abnormal noise caused by contact between the protrusion 22 and the bracket 20.

In addition, the outer peripheral portion 34a and the end surface portion 34b of the elastic member 34 are integrally formed, which simplifies the manufacturing process of the stopper 24.

1 Vehicle body 2 Wheel 4 Front suspension 6 Lower arm 8 Front arm portion 10 Rear arm portion (arm)
10a Rear end (rear end of arm)
12 Mounting portion 14 Mounting portion 16 Front bush 18 Rear bush (elastic bush)
20 bracket 20a flange portion 22 protrusion portion 24 stopper 26 outer cylinder 28 inner cylinder 30 elastic body 32 core member 34 elastic member 34a outer circumferential portion (first elastic member)
34b End surface portion (second elastic member)

Claims (5)

A mounting structure for a vehicle suspension arm, comprising:
A cylindrical bracket fixed to a vehicle body and having a central axis in the front-rear direction of the vehicle body;
a cylindrical elastic bush having a central axis in a vehicle body longitudinal direction, the outer periphery of the elastic bush being held by the inner periphery of the bracket;
an arm that is swingable in the up-down direction of the vehicle body about an axis that passes through the elastic bush and extends in the fore-and-aft direction of the vehicle body, the arm having a rod-shaped rear end that extends rearward of the vehicle body and is held on an inner periphery of the elastic bush, thereby being connected to the bracket via the elastic bush;
a stopper fixed to the rear end of the arm at a position forward of the elastic bush on the vehicle body and on an inner peripheral side of the bracket,
a rear end portion of the stopper is located rearward of a front end portion of the bracket, and when the rear end portion of the arm is displaced a predetermined distance in a vehicle width direction, the stopper comes into contact with an inner periphery of the bracket.
A mounting structure for a vehicle suspension arm. the stopper includes a core member fixed to the rear end of the arm at a position forward of the elastic bushing on the vehicle body, and a first elastic member provided on an outer surface of the core member that faces an inner periphery of the bracket.
2. The vehicle suspension arm mounting structure according to claim 1. the rear end of the arm has a protruding portion that protrudes inward in the vehicle width direction further inward in the vehicle width direction than an inner end of an inner periphery of the bracket, the inner periphery being located forward of the vehicle body front end of the bracket,
When the rear end of the arm is displaced rearward of the vehicle body by a predetermined distance or more, a rear end of the protrusion presses a front end of the bracket.
2. The vehicle suspension arm mounting structure according to claim 1. a second elastic member provided between a vehicle body rear end portion of the protrusion and a vehicle body front end portion of the bracket;
4. The mounting structure for a vehicle suspension arm according to claim 3. the stopper includes a core member fixed to the rear end of the arm at a position forward of the elastic bushing on the vehicle body, and a first elastic member provided on an outer surface of the core member that faces an inner periphery of the bracket,
The first elastic member and the second elastic member are integrally formed.
5. The mounting structure for a vehicle suspension arm according to claim 4.

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