JPH0427042B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rear suspension installed in an automobile.

(Prior Art) In general, in the rear suspension of an automobile, loads are applied to the rear wheels in various directions during driving, such as rearward braking force, upward bump force, and lateral force toward the center of turning. It is known that controlling the rear wheels to change the toe-in in response to the acting force is preferable in terms of improving running stability.

Therefore, conventionally, as a rear suspension that changes the toe-in of the rear wheel in response to the above-mentioned braking force, a wheel support member that rotatably supports the rear wheel,
Two front and rear lateral links that connect the front and rear parts of the wheel support member to the inside of the vehicle body and are swingable in the vertical and longitudinal directions, and the assembly consisting of the wheel support member and the lateral link are moved slightly in the vehicle body longitudinal direction. and a radius link that is elastically connected to the vehicle body in a displaceable manner, and the distance between the connection points of both lateral links with the wheel support member is set smaller than the distance between the connection points with the vehicle body, so that braking force is applied to the rear wheels. When activated, the wheel support member is moved rearward, thereby causing the front part of the wheel support member to be displaced more inwardly within the vehicle body than the rear part in plan view, thereby causing a toe-in change in the rear wheel. (Unexamined Japanese Patent Publication 1973-
153422) has been proposed. In addition, as a rear suspension that changes toe-in of the rear wheel in response to the bump force, a wheel support member that rotatably supports the rear wheel and a front and rear portion of the wheel support member are provided, similarly to the above-mentioned rear suspension. It is equipped with two parallel front and rear lateral links that are connected to the inside of the vehicle body and can swing in the vertical direction, and a radius link that restricts the movement of the wheel support member in the vehicle body longitudinal direction. The link and the rear lateral link are arranged so that the inclination angles are different from each other, so that when a bump force is applied to the rear wheel (during a bump), the connecting part between the front lateral link and the wheel support member is connected to the rear lateral link. It has been proposed to change the toe-in of the rear wheel by displacing the rear wheel more inward than the connecting portion with the wheel support member (see US Pat. No. 3,759,542 and the drawings).

(Problem to be solved by the invention) However, even with a simple structure similar to the rear suspension described above, when a lateral force acts on the rear wheel (during turning), it is difficult to effectively change the toe-in of the rear wheel. The current situation is that nothing has been proposed yet.

The present invention was made in view of such circumstances, and
Even with a simple structure, when a lateral force acts on the rear wheel,
By making the front part of the wheel support member more displaced inward from the vehicle body when viewed in plan than the rear part,
The purpose is to obtain a change in toe-in of the rear wheels.

(Means for Solving the Problems) For this purpose, the present invention has the following configuration. That is, a wheel support member that rotatably supports the rear wheel, and a wheel support member that is arranged in the left-right direction of the vehicle body,
Two front and rear wheels, each of which has its base end attached to the vehicle body via an elastic bushing so as to be freely rotatable in the vertical direction, and its tip end connected to the wheel support member via an elastic bushing so as to be freely rotatable in the vertical direction. a radius link connected to the vehicle body via an elastic bushing so as to restrict the movement of the wheel support member in the longitudinal direction of the vehicle body; A shock absorber is connected to the support member and acts as a shock absorber against the elevation of the rear wheel. Then, the front lateral link is arranged such that the distance between the connection points of both lateral links with the wheel support member is smaller than the distance between the connection points of both lateral links with the vehicle body, so that the end on the wheel support member side is the end on the vehicle body side. It is arranged at an angle in plan view so that it is located at the rear of the vehicle body than the other parts. In addition, the height of the connection point between the front lateral link and the wheel support member is set to be lower than the connection point between the rear lateral link and the wheel support member, so that lateral force is applied to the rear wheel. When this happens, the shared load of the lateral force acting on the two front and rear lateral links is larger on the front lateral link than on the rear lateral link.

(Function) With the above configuration, when a lateral force acts on the rear wheel, a larger external force acts on the connection between the front lateral link and the wheel support member than on the connection between the rear lateral link and the wheel support member. By greatly deforming the elastic bushing of the connecting portion and displacing the front part of the wheel support member more inwardly than the rear part of the vehicle body, the rear wheel changes in the toe-in direction. Further, the front lateral link is arranged so that the distance between the connection points of the two front and rear lateral links with the wheel support member is smaller than the distance between the connection points of the two lateral links with the vehicle body. is arranged to be inclined in plan view so that it is located at the rear of the vehicle body than the vehicle body side end, so that when a lateral force is transmitted to and acts on the front lateral link, a rearward reaction is caused from the front lateral link to the wheel support member. A force is applied, and the reaction force deforms the assembly consisting of the wheel support member and the front and rear lateral links, causing the rear wheel to further change in the toe-in direction.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

1 to 3 show a rear suspension according to the present invention, in which 1 is a wheel support member that rotatably supports a rear wheel 2, 3 and 4 are two lateral links extending in the left-right direction of the vehicle body. Therefore, the lengths of both lateral links 3 and 4 are set to be approximately equal. The base ends of each of the lateral links 3 and 4 are attached to the vehicle body via elastic bushings 5 and 6 having axes parallel to the longitudinal direction of the vehicle body so as to be rotatable in the vertical direction, while Elastic bushings 7 and 8 having axes parallel to the longitudinal direction of the vehicle body are disposed at the front end of the link 3 and at the rear of the wheel support member 1, and at the rear end of the rear lateral link 4, respectively. are connected to each other so as to be rotatable in the vertical direction.

The front lateral link 3 has a wheel support member side end (that is, an elastic bush 7) which is a tip end thereof.
is arranged to be inclined rearward and outward in plan view so that it is located further rearward of the vehicle body than the base end of the vehicle body side end (that is, the elastic bushing 5). The wheel support member side end (i.e., the elastic bushing 8) is located forward of the vehicle body than the base end (i.e., the elastic bushing 6) so that it is inclined forward and outward in plan view. has been done. With this arrangement, the distance between the connection points of both lateral links 3 and 4 with the wheel support member 1 (that is, between the elastic body bushes 7 and 8) is reduced between the connection points of both lateral links 3 and 4 with the vehicle body (that is, between the connection points of both lateral links 3 and 4 with the vehicle body). The distance between the elastic bushings 5 and 6 is set smaller than the distance between the elastic bushings 5 and 6. In addition, the above lateral link 3,
4 are arranged at different levels from each other, and the height of the connection point between the front lateral link 3 and the wheel support member 1 is lower than the connection point between the rear lateral link 4 and the wheel support member 1. is set to
The front lateral link 3 is configured so that when a lateral force acts on the rear wheel 2, the shared load of the lateral force that acts on both the lateral links 3 and 4 is larger on the front lateral link 3 than on the rear lateral link 4. There is.

Further, 10 is a trailing link as a radius link extending in the longitudinal direction of the vehicle body, and the trailing link 10 has its front end attached to the vehicle body.
The rear end portion is rotatably connected to the inner side surface of the wheel support member 1 via elastic bushings 11 and 12, respectively, with respect to a vertical plane in the longitudinal direction of the vehicle body,
Movement of the wheel support member 1 in the longitudinal direction of the vehicle body is restricted.

Further, reference numeral 13 denotes a strut as a shock absorber that acts as a buffer against the rise and fall of the rear wheel 2. The upper end of the strut 13 is rubber-mounted to the vehicle body 14, while the lower end is attached to the wheel support member 1. is connected to the top of the

The structure of the elastic bushing used to connect two members as described above is, for example, in the case of the elastic bushing 7 for connecting the front lateral link 3 and the wheel support member 1, as shown in FIG. An elastic material 17 is filled between the cylinder 15 and the outer cylinder 16, and the outer cylinder 1
6 is fixed to the front lateral link 3, and the inner cylinder 15 is rotatably attached to the wheel support member 1 via a support shaft 18.

Next, the effects of the above embodiment will be explained with reference to FIGS. 5 and 6. When a lateral force Q toward the center of the turn acts on the grounding point _P1 of the rear wheel 2 during turning, , as shown in FIG. 5, the connection points P2, P3 between each lateral link 3, 4 and the wheel support member 1
and the attachment point P4 of the strut 13 to the vehicle body 14
Reaction forces R1, R2, and R3 are generated, respectively.

In this case, the height (ground clearance) a of the connection point P2 between the front lateral link 3 and the wheel support member 1 is the connection point P3 between the rear lateral link 4 and the wheel support member 1.
Since the height is set lower than the height (ground clearance) b, the front lateral link 3 and the wheel support member 1
The ratio of the reaction force R1 at the connection point P2 between the rear lateral link 4 and the reaction force R2 at the connection point P3 between the rear lateral link 4 and the wheel support member 1 is R1/R2=(h-a)/(h-b)> It becomes 1.

However, h is the height (ground clearance) of the attachment point P4 of the strut 13 to the vehicle body 14.

Therefore, the two lateral links 3 and 4 in the front and rear
The shared load of the lateral force Q acting on the front lateral link 3 is larger than that of the rear lateral link 4, and the elastic bushings 5 and 7 at both ends of the front lateral link 3 are Since the elastic bushings 6 and 8 are more strongly influenced by the lateral force Q and change greatly, the front part of the wheel support member 1 is displaced more inward of the vehicle body than the rear part when viewed from the rear. It is possible to change the toe-in so that 2 points toward the inside of the vehicle body with respect to the traveling direction.

Further, the front lateral link 3 is arranged to be inclined rearward and outward in a plan view so that the end on the side of the wheel support member is located at the rear of the vehicle body than the end on the vehicle body side. is arranged so that the side end of the wheel support member is located at the rear of the vehicle body compared to the side end of the vehicle body, so that it is inclined forward and outward in plan view, so that the lateral force Q is transmitted to both the lateral links 3 and 4. As shown in FIG. 6, the shared loads Q1 and Q2 of the lateral force of each lateral link 3 and 4 are applied to connection points P2 and P3 between each lateral link 3 and 4 and the wheel support member 1, respectively. Reaction forces R1a and R2a in the longitudinal direction, which are opposite in direction and equal in magnitude to the longitudinal components Q1a and Q2a, act. In this case, as mentioned above, the shared loads Q1 and Q2 of the lateral force are larger on the front lateral link 3 than on the rear lateral link 4 (Q1>Q2), so the reaction force R1a,
R2a is also larger in the front lateral link 3 (R1a>R2a), and a backward force (R1a-R2a) acts on the wheel support member 1 as a whole. Then, due to this force, both lateral links 3 and 4 rotate around their connection points with the vehicle body, and the connection point P2 between the front lateral link 3 and the wheel support member 1 moves inward to the vehicle body, and the rear lateral link 4 and wheel support member 1
Since the connection point P3 with the rear wheel 2 is displaced outward from the vehicle body, the rear wheel 2 further changes in the toe-in direction.

In this way, when the lateral force Q acts on the rear wheel 2, the load is shared by the two front and rear lateral links 3 and 4.
Due to the difference between Q1 and Q2, the elastic bushings 7 and 8 undergo different deflection deformations, which causes a toe-in change. In addition, a backward reaction force is induced in the wheel support member 1, causing a toe-in change. Stability when turning can be greatly improved.
Furthermore, since there are two means for causing toe-in changes, the degree of freedom in tuning can be improved, and both of these means can change the arrangement layout of the two front and rear lateral links 3 and 4. Since it is a simple change, it can be implemented at low cost.

In the above embodiment, the trailing link 10 whose front end is connected to the vehicle body and whose rear end is connected to the wheel support member 1 is used as the radius link that restricts the movement of the wheel support member 1 in the longitudinal direction of the vehicle body. However, instead of this trailing link 10,
Of course, it is also possible to use a leading link whose front end is connected to the wheel support member and whose rear end is connected to the vehicle body.

Further, in the above embodiment, the distance between the connection points of the two front and rear lateral links 3 and 4 with the wheel support member 1 is set to be smaller than the distance between the connection points of both the lateral links 3 and 4 with the vehicle body. In addition, the front lateral link 3 is arranged to be inclined in plan view so that the end on the side of the wheel support member is located at the rear of the vehicle body than the end on the side of the vehicle body, and the rear lateral link 4 is
Although the wheel support member side end portion is arranged to be inclined in plan view so that the side end portion of the wheel support member is located further forward of the vehicle body than the vehicle body side end portion, the present invention is arranged such that the rear lateral link 4 is arranged substantially straight in the vehicle width direction in plan view. Alternatively, only the front lateral link 3 may be arranged to be inclined in plan view so that the end on the side of the wheel support member is located further rearward of the vehicle body than the end on the side of the vehicle body.

(Effects of the Invention) As explained above, according to the present invention, when a lateral force acts on the rear wheel, the elastic body on the front lateral link side is The bush deforms more than the elastic bush on the rear lateral link side, and a rearward reaction force acts on the wheel support member, deforming the assembly consisting of the wheel support member and the front and rear lateral links. Since the wheels undergo toe-in changes, stability during cornering can be improved, and the degree of freedom in tuning can be increased.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and Fig. 1 is a side view showing the overall structure of the rear suspension, Fig. 2 is a plan view thereof, Fig. 3 is a rear view thereof, and Fig. 4 is a front lateral link. FIG. 5 is an elevational view for explaining the load state when a lateral force is applied, and FIG. 6 is a plan view of the same. DESCRIPTION OF SYMBOLS 1... Wheel support member, 2... Rear wheel, 3, 4... Lateral link, 5, 6, 7, 8... Elastic body bushing, 1
0... Trailing link, 13... Strut (shock absorber), 14... Vehicle body.

Claims (1)

[Claims] 1. A wheel support member that rotatably supports a rear wheel;
They are arranged in the left and right direction of the vehicle body, and each base end is attached to the vehicle body via an elastic bushing so as to be freely rotatable in the vertical direction, and the tip end is attached to the wheel support member via an elastic bushing so as to be freely rotatable in the vertical direction. two connected front and rear lateral links; a radius link connected to the vehicle body via an elastic bushing so as to restrict movement of the wheel support member in the vehicle body longitudinal direction; and an upper end portion attached to the vehicle body; a shock absorber whose lower end is connected to the wheel support member and acts as a buffer against the rise and fall of the rear wheels; The front lateral link is arranged to be inclined in plan view so that the end on the wheel support member side is located further rearward of the vehicle body than the end on the vehicle body side, and
The height of the connection point between the front lateral link and the wheel support member is set to be lower than the connection point between the rear lateral link and the wheel support member, so that when a lateral force is applied to the rear wheel, A rear suspension for an automobile, characterized in that the front lateral link is configured such that the shared load of the lateral force acting on the two front and rear lateral links is greater on the front lateral link than on the rear lateral link.