JPH07117428A - Link member of vehicle suspension - Google Patents

Abstract

PURPOSE:To provide a link member of a vehicle suspension which can greatly enhance the degree of freedom in setting the performance characteristics of the suspension. CONSTITUTION:A link member comprises a rod portion 9 and connecting portions 10, 10 formed at both ends of the rod portion to connect the body side member and the wheel side member of a vehicle to each other. The rod portion comprises a plurality of arched elastic members 9a, 9b. The elastic members are configured to be in symmetry with respect to a plane Q containing an axis P passing the centers of the connecting portions. When either a compressive or tensile force works in the direction of the axis of the connecting portions, the elastic members partially abut to each other and are therefore restrained from undergoing elastic deformation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a link member for a vehicle suspension, and more particularly to a link member having different compression rigidity and tensile rigidity.

[0002]

2. Description of the Related Art As an example of a link member of a rigid axle type suspension or an independent type suspension having a link mechanism, one shown in FIG. 10 is known. In this conventional link member 1, a connecting portion 3 having bush press-fitting holes is integrally formed at both ends of a rod-shaped rod portion 2, and a rubber bush is provided in the bush press-fitting holes of the link member 1. 4 is press-fitted, and a connecting portion of another suspension member is pivotally attached to the rubber bush 4.

[0003]

By the way, the link member 1 having the above-mentioned structure is used, for example, in a parallel link type rigid axle rear suspension shown in the schematic views of FIGS. 11 and 12, a tray extending to the front side of the tire 5. Used as the component members 1A and 1B of the ring link. In this suspension, it is desirable to reduce the tensile rigidity of the upper trailing link 1A when a longitudinal force to the wheel center (W / CTR) such as harshness is input as shown in FIG. On the other hand, when the braking force is input as shown in FIG. 12, it is desirable to increase the compression rigidity of the upper trailing link 1A in order to reduce the rotational vibration angle around AXLE, that is, the change in the windup angle. However, the conventional link member 1 has the axis P
Since the rigidity against compressive force and tensile force acting in the same direction is set to the same level, there is an unsolved problem that the performance characteristics of the suspension cannot be compatible when the longitudinal force is input to the W / CTR and the braking force is input. is there.

The link member 1 is shown in FIGS. 13 and 14.
In the parallel link type independent pendant suspension shown in the schematic diagram, it is also used as the lateral link constituent members 1A and 1B extending in the left and right tire directions. In this suspension, as shown in FIG. 13, when lateral force is input to the tire 5, a link member 1A arranged on the front side of the vehicle is arranged to cause a toe change in the toe-in direction in order to improve turning performance. It is desirable to set the compression rigidity of the lower than that of the one link member 1B. On the other hand, when a braking force is input to the tire 5 as shown in FIG. 14, it is desirable to set the tensile rigidity of the link member 1A high in order to improve steering stability without causing a toe change in the toe-out direction. However, when the link member 1 having the above configuration is used, there is an unsolved problem that the performance characteristics of the suspension cannot be made compatible with each other when the lateral force is input and when the braking force is input.

The present invention has been made in view of the above circumstances, and by being used as a link arm of a vehicle suspension, the link of the vehicle suspension can greatly improve the degree of freedom in setting suspension performance characteristics. It is intended to provide a member.

[0006]

A link member for a vehicle suspension of the present invention constitutes a vehicle suspension interposed between a vehicle body side member and a wheel side member of a vehicle, and includes a rod portion and both ends of the rod portion. A link member that is formed in a portion and that is configured by a connecting portion that connects the vehicle body side member and the wheel side member, wherein the rod portion is formed of a plurality of elastic members curved in an arc shape, and each elastic member is The shapes are plane-symmetric with respect to an arbitrary plane including the axis passing through the centers of the connecting portions. Then, when either one of the compressive force and the tensile force acts in the axial direction of the connecting portion, some of the elastic members come into contact with each other to restrict elastic deformation.

[0007]

According to the link member for a vehicle suspension of the present invention, the link member is curved in an arch shape and is plane-symmetric with respect to an arbitrary plane including an axis passing through the centers of the connecting portions. When arranging multiple elastic members so that their convex curved surfaces face each other, the radius of curvature of each elastic member gradually expands and elastically deforms in response to the action of tensile force in the axial direction on the link member. However, the convex curved surfaces of the elastic members are separated from each other, and the tensile rigidity of the link member is set low. On the other hand, the action of the compressive force in the axial direction on the link member is regulated by the convex curved surfaces of the elastic members interfering with each other, so that the rigidity of the link member is significantly higher than the tensile force. improves.

Further, when a plurality of elastic members are arranged in plane symmetry so that the concave curved surfaces face each other, elastic deformation is caused by the concave curved surfaces against the action of the axial pulling force on the link member. Are regulated by interfering with each other, the tensile rigidity of the link member is set high. on the other hand,
With respect to the action of the compressive force in the axial direction on the link member, the radius of curvature of each elastic member is gradually reduced and elastically deformed,
Since the concave curved surfaces are separated from each other, the tensile rigidity of the link member is set low.

Therefore, in the link member of the present invention, one of the compression rigidity and the tensile rigidity is increased and the other is increased by changing the bending direction of the plurality of elastic members arranged in plane symmetry to each other. Can be set low.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a link member for a vehicle suspension according to the present invention will be described below with reference to the drawings. Figure 1
Shows the link member of the first embodiment. The link member 8 is composed of two plate-like elastic members which are formed of an elastic body such as a steel strip material or an FRP material and which are curved in an arc shape. 9a,
9b and a bush press-fitting portion (connecting portion) 10 integrally formed at both ends of a rod portion 9 composed of these two elastic members 9a and 9b. A bush (not shown) is mounted inside the bush press-fitting portion 10.

The elastic members 9a, 9b are plane-symmetric with respect to a plane Q including an axis P connecting the centers of the bush press-fitting portions 10, 10 formed at both ends.
The center portions of the mutually convex curved surfaces 9c and 9d are arranged in contact with each other. When an elastic force is applied to the elastic members 9a and 9b in the direction of the axis P, they elastically deform as shown in FIG. that time,
The spring constant K in the direction of the axis P shows the same value in both the tension direction and the compression direction as long as the deformation is in a minute range.

When a tensile force is applied to the link member 8, the elastic members 9a and 9b are elastically deformed with the radius of curvature gradually increasing, and the central portions of the abutting convex curved surfaces 9c and 9d are separated from each other. Suddenly (see FIG. 3), the tensile rigidity of the link member 8 has a low spring constant of about 2K. On the other hand, when a compressive force acts on the link member 8, the convex curved surface 9c,
The elastic members 9a, 9b are regulated by the interference of the surface contacting members 9d with each other to receive a compressive force while exhibiting a truss structure (see FIG. 4), and the rigidity of the link member 8 is compared with the above-mentioned tensile force. And significantly improve. Therefore, the link member 8 of the present embodiment is set to a member having low tensile rigidity in the axis P direction and high compression rigidity.

The link member 8 having the above-described structure is used as an upper trailing link of the rigid axle rear suspension shown in FIG. 7, so that the performance characteristics of the suspension at the time of inputting the longitudinal force and the braking force to the W / CTR are obtained. It can be compatible. That is, as apparent from the use of the link member 8 of the present embodiment in place of the link member 1A shown in FIGS. 11 and 12, as shown in FIG. 11, the longitudinal force is input to the wheel center (W / CTR). However, the longitudinal force is immediately attenuated by the link member 8 having low tensile rigidity. Further, even if the braking force is input as shown in FIG. 12, the link member 8 having high compression rigidity can reduce the change in the windup angle and increase the rigidity in the windup direction.

Further, by using the link member 8 having a low tensile rigidity in the direction of the axis P and a high compression rigidity as a wind-up link member of the double wishbone type rear suspension shown in FIG. The same effect as that shown can be obtained. Next, FIG.
Shows a second embodiment of the present invention. The same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

The link member 11 is arranged such that the concave curved surfaces 12c and 12d of the elastic members 12a and 12b, which are curved in an arc shape, which form the rod portion 12, are opposed to each other with respect to the plane Q including the axis P. Are arranged so as to be plane symmetric. Then, the concave curved surface 12d of one elastic member 12b
Includes a stopper 12e protruding toward the elastic member 12a.
Is integrally formed, and its tip end surface is in contact with the concave curved surface 12c of the other elastic member 12a when there is no load.

In this link member 11, when a tensile force acts in the direction of the axis P, elastic deformation is restricted by the concave curved surface 12c and the stopper 12e interfering with each other, so that the tensile rigidity has a high value. Show. On the other hand, when a compressive force acts in the direction of the axis P, the elastic members 12a, 12b
The radius of curvature is gradually reduced and elastically deformed, and the concave curved surface 12c and the stopper 12e that are in contact with each other are separated from each other, and the tensile rigidity of the link member 11 shows a low value. In FIG. 5, the stopper 12e is provided on the concave curved surface 12d side, but even if the stopper is provided on the concave curved surface 12c side, the movement of the elastic members 12a and 12b is similar to that described above.

By using the link member 11 having the above-mentioned structure for the front link of the independent suspension shown in FIG. 9, it is possible to achieve both performance characteristics of the suspension when a lateral force is input and when a braking force is input.
That is, as apparent from the use of the link member 8 of the present embodiment in place of the link member 1A shown in FIGS. 13 and 14, when lateral force is input to the tire 4 as shown in FIG. 13,
The link member 11 having a low compression rigidity causes the toe change in the toe-in direction and the turning performance is improved. Further, even if the braking force is input to the tire 5 as shown in FIG. 14,
Due to the link member 11 having high tensile rigidity, the tire 5 does not undergo a toe change in the toe-out direction, and the steering stability is improved.

Next, FIG. 6 shows a link member of the third embodiment. Note that FIG. 6 (b) is II of FIG. 6 (a).
-II: A sectional view taken along the arrow, Figure 6 (c) shows III-III in Figure 6 (a).
FIG. The link member 13 has a rod portion 1
Four elastic members 14a, 14 in which 4 is curved in an arch shape
It is composed of b and 14c. And the elastic member 1
4a and 14b are plane-symmetric with respect to a plane Q1 including the axis P, and the elastic members 14b and 14c are plane-symmetric with respect to a plane Q2 including the axis P.
Further, the elastic members 14c and 14a are arranged so as to be plane-symmetric with respect to a plane Q3 including the axis P. The planes Q1, Q2, and Q3 are planes that include the axis P and divide the circle around the axis P into three equal parts.

When a tensile force acts on the link member 13, the radii of curvature of the elastic members 14a, 14b, 14c gradually expand and elastically deform, but contact each other as shown in FIG. 6 (c). Convex surfaces 14d, 14e, 14f
Some of them are separated from each other, and the tensile rigidity of the link member 13 shows a low value. On the other hand, when a compressive force acts on the link member 13, the deformation during compression is caused by the convex curved surfaces 14d and 14d.
Since the e and 14f are regulated by interfering with each other, the rigidity of the link member 13 is significantly improved as compared with the tensile force.

Like the link member 8 shown in FIGS. 1 to 4, the link member 13 having the above structure is set as a member having a low tensile rigidity and a high compression rigidity, and the link of the suspension shown in FIGS. 7 and 8. By being used for the arm, the performance characteristics of the suspension can be made compatible when the longitudinal force is input to the W / CTR and the braking force is input.

In each embodiment, the predetermined positions of the elastic members abutting each other and the convex curved surface 9 of the elastic members 9a and 9b are used.
c, 9d, stopper 1 of elastic members 12a, 12b
2e, the concave curved surfaces 12c, and the elastic member 14
A rubber material may be used for d, 14e, and 14f in order to prevent abnormal noise. When the rubber member is adhered to both sides of the abutting portion, it is preferable that the rubber member has a characteristic that rigidity increases with compression.

[0022]

As described above, according to the link member for a vehicle suspension of the present invention, a plurality of members which are plane-symmetric with respect to an arbitrary plane including an axis passing through the centers of the connecting portions. By changing the curving direction of the elastic member in a predetermined direction, it is possible to set one of the compression rigidity and the tensile rigidity to be high and the other to be low. Therefore, the degree of freedom in setting the vehicle suspension characteristics can be increased. It is possible to obtain the effect of being able to greatly improve.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a diagram showing an elastically deformed state of the elastic member according to the present invention with respect to compression and tension acting in the axial direction.

FIG. 3 is a diagram showing a state in which a tensile force acts in an axial direction on the link member of the first embodiment.

FIG. 4 is a diagram showing a state in which a compressive force acts in an axial direction on the link member of the first embodiment.

FIG. 5 is a perspective view showing a second embodiment of the present invention.

FIG. 6 is a diagram showing a third embodiment of the present invention.

FIG. 7 is a perspective view showing a state where the link member of the first embodiment is used as an upper trailing link of a rigid axle rear suspension.

FIG. 8 is a perspective view showing a state in which the link member of the first embodiment is used as a wind up link member of a double wishbone type rear suspension.

FIG. 9 is a perspective view showing a state in which the link member of the second embodiment is used as a front link of an independent suspension.

FIG. 10 is a perspective view showing a conventional link member.

FIG. 11 is a diagram showing a state in which a longitudinal force is input in a parallel link type rigid axle rear suspension.

FIG. 12 is a diagram showing a state in which a braking force is input in a parallel link type rigid axle rear suspension.

FIG. 13 is a diagram showing a state in which a lateral force is input in the parallel link type independent suspension.

FIG. 14 is a diagram showing a state in which a braking force is input in a parallel link type independent suspension.

[Explanation of symbols]

8 Link member of 1st Example 9 Rod part 9a, 9b Elastic member 9c, 9d Convex curved surface 10 Bush press-fitting part (connecting part) 11 Link member 12 of 2nd Example 12 Rod part 12a, 12b Elastic member 12c, 12d Concave curved surface 12e Stopper 13 Link member 14 of the third embodiment 14 Rod portions 14a, 14b, 14c Elastic members 14d, 14e, 14f Convex curved surface P Bushing Pressing hole center plane Q including axis Q1, Q2, Q3 Plane including the axis in the third embodiment

Claims (1)

[Claims] 1. A vehicle suspension that is interposed between a vehicle body side member and a wheel side member of a vehicle, and a rod portion,
A link member that is formed at both ends of the rod portion and that includes a connecting portion that connects the vehicle body side member and the wheel side member, wherein the rod portion includes a plurality of elastic members that are curved in an arc shape. And, each elastic member, with a shape that is mutually plane-symmetric with respect to an arbitrary plane including an axis passing through the center of the connecting portion, among the compressive force or tensile force in the axial direction of the connecting portion. A link member for a vehicle suspension characterized in that, when either one of the forces is applied, a part of the elastic members abut each other to restrict elastic deformation.