JPS6245085B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a rear suspension of an automobile, and particularly to a rear suspension of a trailing arm type such as a semi-trailing arm type or a full trailing arm type. Concerning countermeasures for camber control during rebound.

(Prior Art) Conventionally, as such a trailing arm type rear suspension, as shown in Japanese Patent Application Laid-Open No. 12811/1983, a wheel is rotatably supported,
a semi-trailing arm whose base end is vertically swingably attached to the vehicle body via elastic bushings at at least two locations;
It is known that the wheels are provided with assist links whose other ends are rotatably connected to the vehicle body, and are configured to change the toe-in of the wheels when a lateral force is applied to the wheels.

By the way, it is generally known that it is preferable to control wheel camber changes depending on the driving condition of the vehicle. For example, when the vehicle encounters a bump due to cornering, it is preferable to set the wheels to negative camber, as this improves steering stability during cornering. Further, it is preferable to suppress the camber change of the wheel to a small value when bumps due to rough roads or rebounds occur when the vehicle is traveling straight ahead, since this improves straight traveling performance.

However, with conventional full trailing arm type rear suspensions, there is no camber change in the wheel during bumps or rebound, and with semi-trailing arm type rear suspensions, the wheel camber does not change during bumps or rebound. At present, the camber change is uniquely determined by the inclination of the semi-trailing arm axis, making it impossible to control the camber according to the driving conditions as described above.

(Object of the Invention) In view of the above, an object of the present invention is to provide a trailing arm type rear suspension as described above with a simple configuration in which a camber control mechanism consisting of a link mechanism is appropriately arranged to prevent bumps, The object is to be able to control camber changes according to rebound, and to enable camber control adapted to driving conditions by reducing the degree of interference with the road surface.

(Structure of the Invention) In order to achieve the above object, the technical solution of the present invention is such that the rear wheel is rotatably supported, and the base end is attached to the vehicle body via an elastic bushing so as to be swingable in the vertical direction. In a trailing arm type rear suspension equipped with a trailing arm,
a first whose proximal end is fixed to the trailing arm;
A link mechanism including a control link and a second control link having one end rotatably connected to the tip of the first control link and the other end rotatably connected to the vehicle body is provided, and the second control link is connected in the vertical direction. The pivot point on the vehicle body side is offset by a set amount from the pivot axis of the trailing arm at a position below the connection point with the first control link.

As a result, during bumps and rebounds, the connection point between the first control link and the second control link is adjusted by the offset of the rotation center point on the vehicle body side of the second control link with respect to the swing center axis of the trailing arm. , a difference occurs between the rotation locus of the trailing arm around the pivot axis and the rotation locus of the second control link around the vehicle body side rotation center, and this trajectory difference occurs during bumps and rebounds. The rear wheel camber control amount (correction amount) controls rear wheel camber changes in response to bumps and rebound under the elastic deformation of the elastic bushing that constitutes the center of swing of the trailing arm. This is how it was done.

(Effects of the Invention) Therefore, according to the present invention, by adding a camber control mechanism consisting of first and second control links to an existing trailing arm type rear suspension, the following can be achieved.
This allows you to control the wheel's camber changes in response to bumps and rebound.
Negative camber is possible when driving in turns, which improves steering stability, and camber changes can be suppressed to a small extent when driving straight, improving driving stability.
Therefore, it can greatly contribute to improving the steering stability and running stability of automobiles, and to easily implement them.

In addition, by setting the center point of rotation of the second control link on the vehicle body side in the camber control link mechanism at a position lower than the connection point with the first control link, the ground clearance of the first control link can be increased. It has the advantage of being able to reduce the degree of interference with the road surface.

Furthermore, in the case of the semi-trailing arm type, where the camber change is determined uniquely, the camber change can be controlled, which reduces restrictions on the placement of the semi-trailing arm and increases the degree of freedom in designing the rear suspension. It also has the advantage that it can be increased.

(Example) Hereinafter, an example as a specific example of the technical means of the present invention will be described based on the drawings.

Figures 1 to 4 show an embodiment in which the present invention is applied to a semi-trailing arm type rear suspension having one attachment point on the vehicle body side. It shows.

1 to 4, reference numeral 1 denotes a semi-trailing arm disposed approximately in the longitudinal direction of the vehicle body, and the semi-trailing arm 1 includes a channel-shaped front member 11 and a substantially cylindrical rear member. 1
2 are connected back and forth, and the rear member 12 is
A cylindrical rear wheel support part 121 that rotatably supports the rear wheel W, a connecting part 122 that projects forward from the rear wheel support part 121 and is connected to the rear end of the front side member 11, and a connecting part 122 that extends inward from the connecting part 122. a control link fixing part 123 that protrudes forward and to which a base end of a first control link 31 (described later) is fixed; and the control link fixing part 12
3, a lateral link attachment portion 124 protrudes inwardly from the rear wheel support portion 121 and is used to attach a lateral link 2, which will be described later. On the other hand, the front member 11 is connected to the rear member 1 at its rear end.
The semi-trailing arm 1 is connected and fixed to the connecting portion 122 of the semi-trailing arm 1 with a bolt 13, and its front end (that is, the base end of the semi-trailing arm 1) extends forward.
It is attached to the vehicle body at one point via an elastic bushing 14 so as to be swingable in the vertical direction.

Further, 2 is a lateral link arranged between the semi-trailing arm 1 and the vehicle body,
The lateral link 2 has one end connected to the vehicle body side attachment point of the semi-trailing arm 1 (elastic bushing 1).
4) is rotatably connected to the vehicle body via a ball joint 21 at a position inward of the vehicle body, and the other end is connected to the ball joint 22 at the lateral link attachment portion 124 (near the tip portion) of the semi-trailing arm 1.
The rear wheel W is rotatably connected to the rear wheel W to ensure lateral rigidity against lateral forces acting on the rear wheel W. In addition, this lateral link 2 and the above semi-trailing arm 1 are connected to the rear wheel W.
is configured to be supported so as to be able to swing vertically with respect to the vehicle body, and a straight line connecting the attachment points (elastic bushing 14 and ball joint 21) of the semi-trailing arm 1 and the lateral link 2 on the vehicle body side is formed. The swing center axis l of the semi-trailing arm 1 is inclined at a predetermined angle with respect to the center line in the longitudinal direction of the vehicle body.

3 is the semi-trailing arm 1 mentioned above.
and a lateral link 2, the camber control link mechanism includes a first control link 31 and a second control link 32, and the first control link 31 has its base end connected to the semi- It is fixed to the control link fixing part 123 of the trailing arm 1 (that is, near the rear wheel support part 121) with a bolt 33, and the tip extends inwardly and forwardly and slightly upward. On the other hand, the second control link 32 is arranged in the vertical direction, and its upper end is rotatably connected to the tip of the first control link 32 via a ball joint 34, and its lower end is connected to the vehicle body. They are rotatably connected via a ball joint 35, and the length of the second control link 32 is set shorter than the length of the first control link 31.

Furthermore, the second control link 32 is
As shown in Fig. 1, the rotation center point P on the vehicle body side
(Ball joint 35) is installed to be offset downward by a set amount e with respect to the swing center axis l of the semi-trailing arm 1.

Reference numeral 4 designates a shock absorber arranged in the vertical direction, and the lower end of the shock absorber 4 is placed on a shock absorber mounting portion 125 that protrudes rearward from the rear end portion of the semi-trailing arm 1, that is, the rear wheel support portion 121. The upper end is connected to the vehicle body. Further, 5 is a coil spring arranged around the outer periphery of the shock absorber 4, and 6 is a rear axle shaft.

Next, to explain the effects of the above embodiment, when the rear wheel W bumps or bounces, the rear wheel W swings vertically with respect to the vehicle body via the semi-trailing arm 1, and the base end is swung through a camber control link mechanism 3 consisting of a first control link 31 fixed to the semi-trailing arm 1 and a second control link 32 connected to its tip. In this case, the rotation center point P (ball joint 35) on the vehicle body side of the camber control link mechanism 3 (second control link 32) is set by a set amount e with respect to the swing center axis l of the semi-trailing arm 1. Due to the offset, as shown in FIG. 1, the first control link 31
The connection point Q (ball joint 34) between the semi-trailing arm 1 and the second control link 32 rotates around the pivot axis l of the semi-trailing arm 1, and the rotation trajectory _q1 and the vehicle body of the second control link 32. Rotation locus that rotates around the side rotation center point P
There is a difference between q and ₂ . This trajectory difference becomes the amount of camber control (correction amount) for the camber change of the rear wheel W caused only by the swinging of the semi-trailing arm 1, and this camber control amount allows only the swinging of the semi-trailing arm 1 to change. The camber change of the rear wheel W caused by this is corrected and controlled in accordance with bumps and rebounds based on the elastic deformation of the elastic attachment point (elastic bushing 14) on the vehicle body side of the semi-trailing arm 1.
As a result, the rear wheel W can be made into a negative camber when bumps occur due to cornering, and the steering stability during cornering can be improved. Further, when the vehicle is traveling straight, the camber change of the rear wheel W can be suppressed to a small extent when bumps or rebounds occur due to rough roads, and straight-line traveling performance can be improved. Furthermore, by taking advantage of the difference in order between the amount of bumps when cornering and the amount of bumps when driving on rough roads, you can set the rear wheel to have a negative camber when driving in a corner, thereby reducing the camber when driving straight on rough roads. It can act to suppress the change to a small level, and the above-mentioned compatibility can be achieved.

In addition, the camber control link mechanism 3
By setting the rotation center point P of the second control link 32 on the vehicle body side at a position lower than the connection point Q with the first control link 31,
The control link 31 has a higher ground clearance, which is advantageous in avoiding interference with the road surface.

Furthermore, since it is possible to control camber changes according to bumps and rebounds,
The position of the semi-trailing arm 1, the direction of the swing center axis l, etc. can be freely selected so as not to interfere with the vehicle body, and the degree of freedom in designing the rear suspension can be increased.

In the above embodiment, the present invention was applied to a semi-trailing arm type rear suspension having one attachment point on the vehicle body side, but a semi-trailing arm type rear suspension having two attachment points on the vehicle body side was described. Of course, the present invention can also be applied to a full trailing arm type, and in particular, in the case of a full trailing arm type, it is effective for negative camber control of the rear wheel during cornering.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic explanatory diagram showing the rear suspension structure for the right rear wheel, FIG. 2 is a plan view of the same, and FIG. 3 is a rear view of the vehicle as seen from the rear. FIG. 4 is a side view seen from inside the vehicle body. DESCRIPTION OF SYMBOLS 1... Semi-trailing arm, 14... Elastic bushing, 3... Camber control link mechanism, 31... First control link, 32...
Second control link, W...Rear wheel,
l...Semi-trailing arm swing center axis,
P...Rotation center point on the vehicle body side of the second control link.

Claims (1)

[Claims] 1. A trailing arm that rotatably supports the rear wheel and whose base end is attached to the vehicle body via an elastic bushing so that it can swing vertically, and a first control link whose base end is fixed to the trailing arm. and a second control link, one end of which is rotatably connected to the tip of the first control link, and the other end of which is rotatably connected to the vehicle body,
The second control link is arranged in the vertical direction, and its rotation center point on the vehicle body side is offset by a set amount from the swing center axis of the trailing arm at a position below the connection point with the first control link. A rear suspension for an automobile, characterized in that it is installed at a