JPH0780404B2 - Automobile independent suspension type rear suspension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Purpose of the Invention (1) Field of Industrial Application The present invention relates to an independent suspension type rear suspension device for an automobile, and more particularly to a rear suspension device that extends in the vehicle front-rear direction and has its front end supported on the vehicle body via an elastic bush. Rear left and right rear wheels to the left and right lower control arms respectively having a first arm portion and a second arm portion extending in the vehicle body left-right direction and having an inner end supported by the vehicle body through an elastic bush. The present invention relates to a device of a type in which left and right hub carriers, which respectively rotatably support each other, are rotatably supported.

(2) Conventional technology The independent suspension type rear suspension of this type is one of the attractive structures in terms of space efficiency, but on the other hand,
Difficult problems arise in terms of the forces acting on the bush if sufficient compliance is required. That is, when passing over a convex portion of the road surface of a wheel, when an external force in the vehicle front-rear direction is applied, a moment and a shearing force are exerted, so that it is difficult to ensure compliance unless each bush is made flexible. However, if the bush is made flexible, the lateral rigidity and the toe rigidity are reduced, which causes an adverse effect that sufficient resistance cannot be exerted against an external force (lateral force) in the vehicle left-right direction such as centrifugal force generated during turning.

Therefore, conventionally, as disclosed in U.S. Pat. No. 4,157,840, there has been proposed a device in which the second arm portion is formed of a leaf spring to separate the forces.

(3) Problems to be Solved by the Invention In the above-mentioned conventional technique, the strength of the leaf spring against lateral load is
It is difficult to satisfy both the flexural rigidity in the front-rear direction and it is not fully satisfactory.

The present invention has been proposed in view of the above circumstances, and has an independent suspension rear suspension for an automobile, which has sufficient flexibility with respect to a longitudinal force of the vehicle and can secure sufficient rigidity with respect to a lateral force of the vehicle. The purpose is to provide a device.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a carrier support portion that swingably supports a hub carrier that supports left and right rear wheels, and a carrier support portion. A first arm portion extending from the support portion to the front of the vehicle body and a second arm portion extending from the carrier support portion to the inside of the vehicle body left-right direction constitute left and right lower control arms, and a single body extending in the vehicle body left-right direction. Both end portions of the sub-frame are supported by the vehicle body via left and right elastic bodies that can be elastically deformed to allow the sub-frame to swing in the vehicle front-back direction. The first and second left and right lower control arms are supported by the sub-frame at the positioned positions via the elastic bushes for the inner ends of the respective second arm portions of the left and right lower control arms. Wherein the front end of that supported on the vehicle body via respective elastic bushes.

(2) Operation According to the above configuration, the sub-frame can swing in the vehicle front-rear direction due to the elastic deformation of the elastic body when a force in the vehicle front-rear direction is applied to the sub-frame from the wheels via the lower control arm. (2) Since the support position of the inner end of the arm part to the subframe and the support position of the subframe to the vehicle body are vertically offset, the lower control arm can move in the front-rear direction even with a slight swing angle displacement of the subframe. It is fully displaceable and ensures the required compliance.

The sub-frame is stably supported by the vehicle body with a long span in the left-right direction by both ends, and also has a lateral force acting portion (carrier bearing portion) that the lower control arm receives from the wheels in the lateral direction. Since it is located at a position substantially coincident with the front-rear direction and is connected to the acting portion through the second arm portion with almost no displacement in the front-rear direction, this subframe does not increase the unsprung weight particularly and The lateral force can be firmly received without applying a particularly large load to the elastic bush at the inner end of the second arm portion.

Further, since the sub-frame supports only the second arm of each lower control arm (that is, the first arm directly supports the vehicle body), the size and weight of the sub-frame itself can be reduced. It is easy to swing the subframe back and forth as described above.

(3) Embodiment Hereinafter, one embodiment of the present invention will be described with reference to the drawings. First, in FIG. 1 to FIG. 3, a left rear wheel 1 of a vehicle is rotatably supported by a hub carrier 2. A lower control arm 4 supported by a vehicle body 3 is swingably supported at 2. Since the right rear wheel is also supported in exactly the same manner as the left rear wheel 1, only the part related to the left rear wheel 1 will be described below, and the description of the right rear wheel will be omitted.

The lower control arm 4 includes a carrier support portion 7 that supports the hub carrier 2, a first arm portion 5 that extends from the carrier support portion 7 forward of the vehicle body, and a first arm portion 5 that extends inward from the carrier support portion 7 inward in the vehicle left-right direction. It is composed of two arms 6. The carrier support portion 7 is formed in a substantially U-shaped shape when viewed from above, and the hub carrier 2 has a support shaft 9
In addition, it is swingably supported by the carrier support portion 7 via an elastic bush (not shown).

The front end 5a of the first arm portion 5 is supported by the vehicle body 3 via a bush (not shown). Also, the inner end 6a of the second arm portion 6
Are supported by the sub-frame 10 which will be described in detail below.

The sub-frame 10 includes a frame main body 10m that extends in a substantially straight line in the vehicle left-right direction, and relatively short left and right arm portions that rise upward and incline upward from both left and right ends of the main body 10m.
The upper ends e of both arm portions 10a are supported by elastic bodies 11 such as rubber bushes on both left and right sides of the vehicle body. As will be described later, 11 can allow the swing displacement of the subframe 10 in the front-rear direction due to its own elastic deformation.

The inner end 6a of the corresponding second arm portion 6 of the lower control arm 4 is connected and supported near the connecting portion between each arm portion 10a of the subframe 10 and the frame body 10m via an elastic bush (not shown). . Thus, the second arm portion 6
Since the supporting position of the sub-frame 10 is deviated downward with respect to the supporting position of the sub-frame 10 on the vehicle body 3 (position of the elastic body 11), for example, in the frame main body 10m of the sub-frame 10. When a large external force in the front-rear direction is applied, the elastic deformation of the elastic body 11 allows the sub-frame 10 to swing forward and backward.

Next, the operation of this embodiment will be described with reference to FIG. 4. When a rearward vehicle force is applied to the sub-frame 10 from the lower control arm 4 during braking, the supporting position of the sub-frame 10 on the vehicle body 3 will be described. Is at a position higher than the supporting position of the second arm portion 6 of the lower control arm 4 on the sub-frame 10, the sub-frame 10 swings rearward as shown by the broken line while bending the elastic body 11,
The lower control arm 4 can be sufficiently displaced to the rear side, and necessary compliance can be secured.

In such a rear suspension device, a subframe
10 is supported by the vehicle body 3 with a long span in the left-right direction on both sides, and is also supported by the carrier support portion 7 which is a portion acting on the lower control arm 4 from the rear wheel 1 in the left-right direction, that is, the lateral force. The unframed weight is particularly increased by the sub-frame 10 because it is connected to the support portion 7 and the second arm portion 6 at a position substantially coincident with each other with almost no displacement in the front-rear direction. None and the second arm portion 6
It is possible to firmly receive the lateral force without applying a particularly large load to the elastic bush of the inner end 6a.

Further, if the torsional rigidity of the sub-frame 10 is made sufficiently high, the rate of association on the left and right increases, so that stability against disturbance can be improved.

C. Effects of the Invention As described above, according to the present invention, both ends of a single sub-frame extending in the left-right direction of the vehicle body can be elastically deformed to allow swinging of the sub-frame in the vehicle front-rear direction. left,
While supporting each through the right elastic body and supporting the inner ends of the respective second arm portions of the left and right lower control arms at the positions deviated in the vertical direction from the supporting portions, Since the front ends of the first arm portions of the control arm are respectively supported by the vehicle body, the sub-frame is formed by the elastic deformation of the elastic body when a force in the vehicle front-rear direction is applied to the sub-frame from the wheels via the lower control arm. It is possible to swing in the front-back direction, and since the support position of the inner end of the second arm portion to the subframe and the support position of the subframe to the vehicle body are vertically offset, a slight swing angle of the subframe Even with displacement, the lower control arm can be sufficiently displaced in the front-rear direction, and necessary compliance can be secured.

The sub-frame is stably supported by the vehicle body with a long span in the left-right direction by both ends and is substantially aligned in the front-rear direction with the action portion of lateral force received from the wheels by the lower control arm (that is, the carrier support portion). Since it is located at the position and is connected to the acting portion via the second arm portion with almost no displacement in the front-rear direction, the subframe does not increase the unsprung weight and the inner end of the second arm portion is not increased. The lateral force can be firmly received without applying a particularly large load to the elastic bush. As a result of the above,
An extremely high-performance rear suspension is obtained that has a good riding comfort due to the reduction of unsprung weight, and has sufficient flexibility with respect to the longitudinal force of the vehicle and sufficient rigidity with respect to the lateral force. .

Further, since the sub-frame supports only the second arm portion of each lower control arm (that is, the first arm portion is directly supported by the vehicle body), the size and weight of the sub-frame itself should be reduced accordingly. Therefore, the back-and-forth swinging of the sub-frame is easy, and the response of the compliance can be enhanced.

In addition, since the above subframes can be commonly used for the left and right lower control arms, the structure can be simplified, and the cost can be reduced and maintenance workability such as disassembly and maintenance can be greatly improved. it can.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a perspective view, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is a simplified side view for explaining the operation. 1 ... rear wheel, 1 ... hub carrier, 3 ... car body, 4 ...
Lower control arm, 5 …… First arm, 5a ……
Front end, 6 ... second arm, 6a ... inner end, 10 ... subframe, 11 ... elastic body

Claims (1)

[Claims] 1. A carrier support portion (7) for swingably supporting a hub carrier (2) supporting left and right rear wheels (1).
The first arm portion (5) extending from the carrier support portion (7) to the front of the vehicle body and the second arm portion (6) extending from the carrier support portion (7) to the left and right in the vehicle body from the left and right sides. Each lower control arm (4) of the above is configured so that both ends of a single subframe (10) extending in the left-right direction of the vehicle body are allowed to swing in the vehicle body front-rear direction with respect to the vehicle body (3). The left and right lower control arms are supported by the left and right elastic bodies (11) that can be elastically deformed so that they are vertically displaced from the supporting portions on the subframe (10). Each second arm part (6) of (4)
Support the inner end (6a) of each via elastic bushing,
An independent suspension system for an automobile, characterized in that the front ends (5a) of the respective first arm portions (5) of the left and right lower control arms (4) are supported on the vehicle body (3) through elastic bushings, respectively. Rear suspension device.