JPS6053413A - Rear suspension of car - Google Patents

Abstract

PURPOSE:To improve the traveling stability of a car by supporting a wheel bearing member with a swing arm extending along the car body and three lateral links extending across the car body and by setting one of the fitting points of the lateral links to the wheel bearing member rearward from the receiving point of the transverse force to the wheel. CONSTITUTION:A swing arm 18 is provided, which is plate-shaped (vertically wide) and extending along the car body and which is fixed, at one end, to the car body via a horizontal transverse shaft 38 in such a manner as to permit free rotation about this shaft and also fixed, at the other end, to a wheel bearing member 12 with a bolt 30. Also the first through third lateral links 20, 22, 24 are provided, each of which is fixed, at one end, to the wheel bearing member 12 via a horizontal shaft extending practically along the car body in such a manner as to permit free rotation about this shaft and also fixed, at the other end, to the car body in the same manner, permitting free rotation. In this case, the fitting point to the wheel bearing member 12 of the second lateral link 22 is set on the upper side than those of the other lateral links 20, 24, and, in addition, the fitting point of the third laterial link 24 is set backward from the receiving point P of the transverse force to a wheel 10.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to improvements in rear suspensions for automobiles.

(Prior Art) A system called a trailing arm type or a semi-trailing arm type has been known as an independent rear suspension for automobiles.

This rear suspension system has a trailing arm that extends in the longitudinal direction of the vehicle and is attached to the vehicle body so that its front end can swing vertically.The rear end of this trailing arm has a hub support for supporting the wheel hook. The member is fixed. Additionally, a Dan's arm is disposed between the rear end of the trailing arm and the vehicle body above it. This type of rear suspension has a simple structure and can be made lightweight, but in order to sufficiently increase the lateral rigidity of the trailing arm, its cross-sectional shape must be made large, and the attachment points to the vehicle body must be It becomes necessary to widen the horizontal distance between
The trailing arm becomes large, which is disadvantageous in terms of weight.

A structure to solve such problems was developed in U.S. Pat.
This was proposed in No. 2Ojt. In this proposed structure, the front end of the trailing arm extending in the longitudinal direction of the vehicle body is swingably attached to the vehicle body, the wheel knob is supported at the rear end, and the trailing arm has a The outer ends of the vertically arranged lateral links are connected to a rotating member, and the inner ends of the lateral links are rotatably connected to the vehicle body. This type of rear suspension is advantageous in that it is not necessary to make the stiffness of the trailing arm very high. Also during downward movement, i.e. rebound,
Because the wheels tend to move in the toe-out direction,
Steering instability such as autosteer occurs when driving on a curved road.

(Object of the present invention) An object of the present invention is to suppress the tendency to toe out due to vertical movement of wheels in a rear suspension having a swing arm extending in the longitudinal direction of the vehicle body and a lateral link extending in the lateral direction. To provide a rear suspension for an automobile which can also effectively suppress toe-out tendency against lateral force applied to wheels when turning, and can therefore further improve driving stability. be.

(Configuration of the present invention) In order to achieve the above object, the present invention is configured as follows. That is, the present invention extends in the longitudinal direction of the vehicle body, has one end attached to the vehicle body so as to be swingable in the vertical direction, supports a wheel support member at the other end, and applies a force in the longitudinal direction and a rotational force in the wheel rotation direction to the wheel support member. It comprises a swing arm configured to be able to transmit transmission, and three lateral links extending in the lateral direction of the vehicle body independently of each other, one end of each lateral link being rotatably attached to the wheel support member, and the other end being rotatably attached to the vehicle body. , the wheel side attachment points of the wheel support member of the seven lateral links are also arranged above the attachment points of the other two lateral links, and at least one of the attachment points of the one lateral link is disposed above the attachment points of the other two lateral links. One feature is that it is located behind the point where lateral force is applied to the wheel.

According to this configuration of the present invention, the posture of the wheel support member, and therefore the wheel, is regulated only by the three lateral links, and the arrangement of the three lateral links, that is, the vertical and vertical directions of each lateral link. The inclination angle and length in the longitudinal direction, the mounting position to the wheel support member, and the lateral rigidity at the mounting position should be determined appropriately. It becomes possible to control the toe change and the can r4 angle change of the wheel to a desired tendency when the direction is applied.

In the present invention, seven of the three lateral links (1) are attached to the wheel support member above the other two, and at least seven of the three lateral links attached below are attached to the wheel support member. are located behind the point of application of lateral force to the wheel during turning, so the rubber bushing U that attaches these lateral links to the wheel support member is
By appropriately determining the force, the toe angle relative to the lateral force can be controlled to a desired tendency in this lower direction.

The swing arm only needs to have the strength and rigidity to transmit force in the longitudinal direction of the vehicle body and rotational force in the wheel rotation direction.
It is necessary not to impose constraints on the attitude control of the wheels by the three lateral links. For this purpose,
By lowering the lateral rigidity of the swing arm, the bang,
The swing arm is made to be able to deflect laterally when hitting a mound, etc., or the swing arm is attached to the vehicle body so that it can be displaced laterally, or the swing arm and the wheel support member are coupled so that relative displacement is possible. The swing arm may be configured to allow lateral displacement of the wheel support member by any of the following methods.

(Effects of the Invention) According to the present invention, three lateral links extending in the lateral direction of the vehicle body are provided, and the attachment points of these lateral links σ) to the vehicle body support member are located higher than the other two. In addition, at least seven of the lower wheels are located behind the point where lateral force is applied to the wheel during turning, so the toe change of the wheel is caused by one of these lower wheels. The toe-out tendency can be suppressed by the lateral link. By appropriately selecting the rigidity of the rubber bushing that attaches the lower lateral link to the wheel support member, it is possible to cause a slight toe-in change in response to a lateral force. In addition, by making the stiffness of the bushes equal and arranging them so that the reaction force against the lateral force of the lower front link is greater than that of the lower rear link, the above toe-in change can be obtained and running stability can be improved. can be improved.

(Description of Embodiments) Referring to FIGS. 1 to 3, a wheel 10 is rotatably supported by a wheel support member 12, and a suspension stiffening device 1
4 to the vehicle body 16. The bus suspension device 14 includes a swing arm 18, a first lateral link 20, a second lateral link 22, and a third lateral link 2.
4 and a shock absorber 26.

The swing arm 18 has a plate shape with a wide width from top to bottom, extends in the longitudinal direction of the vehicle body, and its front end is attached to a bracket 29 provided on the main frame 28 of the vehicle body through a rubber bush 39 that is integrated with the swing arm 18 and rotates around a horizontal axis in the lateral direction of the vehicle body. It is movably mounted, and the rear end is fixed to the wheel support member 12 by a bolt 30. The first lateral link 20 extends substantially laterally with respect to the vehicle body, and has one end attached to the wheel support member 12. The first lateral link 20 has a rubber bush 20 a that is rotatable about a horizontal shaft in the longitudinal direction of the vehicle body.
tijP Sea C is attached, the other end is the main frame of the vehicle body 2
Similarly to 8, rotation 0I around the horizontal axis in the longitudinal direction of the vehicle body.
It is functionally attached via a rubber bush 20b. The 2nd lateral link 22 and the 3rd lateral link 24 are
One end is attached to the wheel support member 12 via rubber bushings 22a and 24a, respectively, so as to be rotatable around a horizontal axis υ in the longitudinal direction of the vehicle body, and similarly attached to the rear length bar frame 32 on the vehicle body side via rubber bushings 22b and 24b. It is mounted so that it can be rotated around a horizontal axis in the longitudinal direction of the vehicle body. The shock absorber 26 is provided with a coil spring 34 and a spring spring 36, and extends in the vertical direction.The lower end is attached to the wheel support member 12 so as to be rotatable around a horizontal axis in the lateral direction of the vehicle body, and the upper end is attached to the vehicle body 16. Mounted to allow rotational displacement.

When the wheel 10 receives a force in the vertical direction, the wheel 10 is displaced in the vertical direction, and the swing arm 18 swings around the lever 38 for attaching its front end to the vehicle body.

Therefore, the wheel support member 12
It will be displaced along an arcuate trajectory centered on the bolt 38 at the front end of. In this case, since the wheel support member 12 is laterally supported by the three lateral links 20, 22, 24, the lateral links 20, 22, 24 also swing vertically, and their outer ends swing. Displaces laterally with movement. In the illustrated embodiment of the lateral link arrangement, the first lateral link 20 is inclined laterally outwardly and slightly rearwardly downward, and has the longest length among the three lateral links. It's short. The second lateral link 22 is laterally outwardly inclined slightly forward and upwardly, and the third lateral link 24 is laterally outwardly inclined slightly downwardly. In this arrangement, for example, considering a fit in which the wheel is displaced upward, the outer end of the first lateral link 2o will be slightly displaced outward along the curve 20C in FIG. 2, but the link 20 will move backward. Since it has a slope of , the amount of outward displacement is small. The outer end of the lateral link 22 moves inward as the wheel moves upward. Also,
Although the outer end of the third lateral link 24 is displaced along the curve C in FIG. 2, the amount of displacement in the lateral direction of the vehicle body is extremely small.

Since the outer end of the first lateral link 20 is located forward of the outer end of the third lateral link 24, there is almost no toe-in change as a whole, and the second lateral link 20
Since the outer end of No. 2 is located above the other links, the camber angle will decrease. A downward displacement or rebound of the wheel results in a slight toe-in and a slight increase in camber angle 710'. That is, in response to vertical displacement of the wheel, a toe angle change occurs as shown by curve ia in FIG. 6, and a camber angle change tends as shown in FIG. 6 C. The curve in Figure 6 is Mikaiaki! This figure shows the Kelto angle change in the suspension of Otsu-6.220j, and from this figure, the excellent effect of toe angle control in this example can be recognized.

With this change in the attitude of the wheel, the swing arm 1
The rubber bushing 39 that attaches the swing arm 18 to the vehicle main frame 28 has an axial deviation, so that the swing arm 18
produces the required lateral displacement of 1.

In addition, when lateral forces are applied to the wheels differently, such as when driving on a curve, since the first lateral link 20 and the third lateral link 24 are arranged before and after the lateral force application point P, the toe angle is Change is regulated and no major changes occur. Therefore, the toe-out tendency is effectively suppressed. In this case, for example, the rigidity of the rubber bushing 20a of the fifteenth lateral link 20 is made smaller than the rigidity of the rubber bushing 24a of the third lateral link 24, so that the lateral displacement of the first lateral link 20 is smaller than that of the third lateral link 24. If it is made larger, a slight toe-in change can be obtained with respect to lateral force, and running stability can be further improved.

FIG. 3 shows another embodiment of the present invention, in which the same parts as in the previous example are denoted by the same reference numerals. In this example, the arrangement of three lateral links 20, 22, and 24 is changed. Referring to FIG. 5, the mounting positions of the lateral links 20, 22, and 240 on the wheel support member 12 are not aligned in a vertical plane in the longitudinal direction of the vehicle body, and the first lateral link 20 is attached to the axle shaft. The second lateral link 2 is located above and in front of 4o.
2 is located above and in front of the axle 40, and the third
The lateral links 24JI and 24JI are respectively attached at positions below and at the rear of the axle 40. Even with this arrangement, the effect is the same as the previous example.

Furthermore, with this arrangement, there is almost no change in toe angle in the front and rear directions.

The present invention is not limited to the arrangement of the embodiments described above, but can change the camber angle and toe angle of the wheel by variously changing the arrangement of the lateral link, the position and rigidity of the attachment point to the wheel support member. It is possible to make this a desirable trend.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the suspension of the present invention;
Figure 2 is a rear view, Figure 3 is a perspective view, Figure ≠ is a cross-sectional view taken along line A-A in Figure 1, Figure 5 is a side view seen from the inside, and Figure 6 shows the force exerted by the wheel in the vertical direction. Explanation of symbols 10...0 Wheel 12...Wheel support member 14...Suspension device 18...Swing arm 201I0...・First lateral link 22.0...Third lateral link 24@■--Third lateral link 26-fist 0・Stain absorber 28...Vehicle main frame Fig. 1 Fig. 2 Fig. 3 Figure 4

Claims (1)

[Claims] It extends in the longitudinal direction of the vehicle body, has one end attached to the vehicle body so as to be swingable in the vertical direction, supports a wheel support member at the other end, and is configured to be capable of transmitting force in the longitudinal direction and rotational force in the wheel rotation direction to the wheel support member. Equipped with a swing arm and three lateral links that extend in the lateral direction of the vehicle independently from each other,
One end of each lateral link is rotatably attached to the wheel support member, and the other end is rotatably attached to the vehicle body, and the attachment point on the wheel side of the wheel support member of the seven lateral links is attached to the attachment point of the other one lateral link. A rear suspension for an automobile, characterized in that at least seven of the attachment points of the two lateral links are arranged behind a point where lateral force is applied to the wheel.゛