JPH0474204B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to rear suspensions for automobiles, and particularly to rear suspensions of a trailing arm type such as a semi-trailing arm type and 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 Laid-Open No. 58-12811, 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.

(Problems to be Solved by the Invention) By the way, it is generally known that it is preferable to control wheel camber changes depending on the driving condition of the automobile. For example, when turning, the car body rolls due to centrifugal force, so when bumping, the outer wheel of the turning wheel is moved into a negative camber (when viewed from the front, the upper end of the wheel tilts inward into the car body) where the ground camber angle is zero. It is preferable to set the vehicle to a state in which the vehicle is in a state where the vehicle is in a state where the vehicle is in a state where the vehicle is in a state where the vehicle is in a state where the vehicle is in a state of In addition, it is preferable to suppress the camber change of the wheel to a small value during bumps and rebounds due to rough roads during straight-ahead travel, since canvas thrust can be prevented and straight-ahead travel performance can be improved.

However, in the conventional full trailing arm type rear suspension, camber changes do not occur in the wheel during bumps and rebounds. In addition, in the case of semi-trailing arm type wheels, the change in camber of the wheel during bumps and rebounds is primarily determined by the inclination of the semi-trailing axis, and as mentioned above, the camber changes depending on the driving condition. The current situation is that control is not possible.

On the other hand, US Pat. No. 3,333,654 and the drawings disclose a trailing suspension equipped with a link for correcting camber changes. However, in this conventional technology, since the drive shaft is configured to restrict the lateral displacement of the wheel, the tilting axis of the arm is tilted significantly toward the longitudinal direction of the vehicle body. As a result, the tread change due to the vertical movement of the wheels becomes too large, which causes problems such as deterioration of straight-line stability and wear of the tires. Furthermore, in order to regulate the lateral force that enters the wheels, the structure of the driveshaft joint must be complicated, which increases costs and makes it difficult to use the commonly used constant velocity joints. It is.

In view of the above, an object of the present invention is to efficiently control camber changes in response to bumps and rebounds using a simple configuration in which a camber control mechanism consisting of a link mechanism is installed at an appropriate position in a trailing arm type rear suspension. The objective is to enable camber control that is well controlled and adapted to the driving conditions.

(Means for Solving the Problems) In order to achieve the above object, the technical solution of the present invention is to support a rear wheel rotatably, so that the base end can swing vertically relative to the vehicle body via an elastic bushing. A trailing arm is attached to the vehicle body, one end of which is attached to the vehicle body at a position inside the vehicle body from the attachment point of the trailing arm on the vehicle body side, and the other end of which is attached to the vehicle body through a ball joint near the rear hole support portion of the trailing arm. A lateral link that is rotatably connected, a first control link whose base end is fixed to the trailing arm, 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. and a second control link. 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, and the connection point with the first control link is is located in a horizontal plane that includes the pivot axis of the trailing arm during setting, and is installed so as to be offset by a predetermined amount in the longitudinal direction of the vehicle with respect to the pivot axis of the trailing arm.

(Function) As a result, during bumps and rebounds, the rotation locus around the pivot axis of the trailing arm and the vehicle body of the second control link at the connection point of the first control link and the second control link. A large difference occurs between the rotation trajectory around the side rotation center point, and this trajectory difference becomes the amount of camber control (correction amount) of the rear wheel during bumps and rebounds, and the swinging of the trailing arm. The camber change of the rear wheel is efficiently controlled in response to bumps and rebound under the elastic deformation of the elastic bushing that forms the center point.

(Effects of the Invention) Therefore, according to the present invention, a camber control link mechanism consisting of a first and a second control link is added to an existing trailing arm type rear suspension equipped with a trailing arm and a lateral link. This simple configuration allows for efficient control of wheel camber changes in response to bumps and rebounds, making it possible to achieve negative camber that reduces the ground camber angle to zero when turning, thereby improving maneuverability. It is possible to improve stability, and it is also possible to suppress the camber change during straight running to improve running stability, thereby greatly contributing to improving the handling stability and running stability of automobiles and to easily implement them. .

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.

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. The figure shows a rear suspension structure for the right rear wheel W.

In FIGS. 1 to 4, reference numeral 1 denotes a semi-trailing arm arranged substantially in the longitudinal direction of the vehicle body.
The semi-trailing arm 1 is formed by connecting a channel-shaped front member 11 and a substantially cylindrical rear member 12 back and forth. The rear side member 12 includes a cylindrical rear wheel support part 121 that rotatably supports the rear wheel W, and the rear wheel support part 12.
a connecting part 122 that projects forward from the connecting part 122 and is connected to the rear end of the front member 11; and a control link fixing part 1 that projects inwardly and forwardly from the connecting part 122 and to which the base end of a first control link 31, which will be described later, is fixed.
23, and a lateral link attachment portion 124 that protrudes inward from the rear wheel support portion 121 near the control link fixing portion 123 and is used to attach a lateral link 2, which will be described later. On the other hand, the front member 11 is connected and fixed at its rear end to a connecting portion 122 of the rear member 12 with bolts 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 B.
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 B via a ball joint 21 at a position inward of the vehicle body, and the other end is connected to the lateral link attachment portion 124 of the semi-trailing arm 1 (near the tip, that is, the rear wheel support portion). 121) via a ball joint 22 to ensure lateral rigidity against lateral forces acting on the rear wheel W. The lateral link 2 and the semi-trailing arm 1 are configured to support the rear wheel W so as to be able to swing vertically relative to the vehicle body, and both the semi-trailing arm 1 and the lateral link 2 Attachment point on the vehicle body side (elastic bushing 1)
4 and the ball joint 21), that is, 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.
This is a camber control link mechanism consisting of a first control link 31 and a second control link 32, which are arranged between the lateral link 2 and the lateral link 2. The base end of the first control link 31 is fixed to the control link fixing part 123 of the semi-trailing arm 1 (in other words, near the rear wheel support part 121) with a bolt 33, and the tip part is fixed to the inside. It extends forward and slightly upward. On the other hand, the second control link 32 is arranged in the vertical direction, and its lower end is rotatably connected to the tip of the first control link 31 via a ball joint 34, and its upper end is connected to the vehicle body B. is rotatably connected to via a ball joint 35. Further, 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
The rotation center point P on the vehicle body side (ball joint 35)
is offset by a set amount e above the vehicle body with respect to the swing center axis l of the semi-trailing arm 1, and the connecting point Q (ball joint 34) with the first control link 31 is set to the semi-trailing arm during setting. It is located within a horizontal plane H (see FIG. 5) that includes the swing center axis l of the arm 1, and is installed so as to be offset by a predetermined amount toward the front of the vehicle body with respect to the swing center axis l.

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 rebounds, 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 second control link 32 of the camber control link mechanism 3 is arranged in the vertical direction, and its pivot point P (ball joint 35) on the vehicle body side is the pivot center of the semi-trailing arm 1. It is offset by a set amount e with respect to the axis l, and the connection point Q (ball joint 34) with the first control link 31 is located within the horizontal plane H including the swing center axis l of the semi-trailing arm 1 at the time of setting. By installing the semi-trailing arm 1 so as to be offset by a predetermined amount toward the front of the vehicle body with respect to the swing center axis l, as shown in FIG. The rotation locus q ₁ that rotates around the rotation center axis l and the rotation locus q ₂ that rotates around the vehicle body side rotation center point P of the second control link 32 intersect with each other, and both rotations intersect with each other. A large difference occurs between the dynamic trajectories q ₁ and q ₂ . This trajectory difference is
The amount of correction in the positive direction of the camber control for the camber change of the rear wheel W that occurs when only the semi-trailing arm 1 is swung, assuming that the first and second control links 31 and 32 are not present. becomes. In other words, the actual amount of camber control that takes this correction amount into account is the semi-trailing arm 1 during bumps and rebounds.
This is obtained by elastic deformation of the elastic attachment point (elastic bushing 14) on the vehicle body side.

This allows the rear wheel W to have a negative camber that makes the ground camber angle zero when bumps occur due to cornering, and it is possible to improve steering stability during cornering. Also, when driving straight,
During bumps and rebounds caused by rough roads, camber changes in the rear wheel W can be suppressed to a small level, and straight-line driving performance can be improved. Furthermore, by utilizing the difference in order between the amount of bumps when cornering and the amount of bumps when driving on rough roads, the rear wheel W
If the vehicle is set to have a negative camber when the vehicle is turning, the camber change when traveling straight on a rough road can be suppressed to a small extent, and the above-mentioned properties can be achieved.

Moreover, the base end of the semi-trailing arm 1 is attached to the vehicle body at one point via the elastic bush 14, and the vicinity of the tip (lateral link attachment portion 124) is attached to the vehicle body via the lateral link 2. Therefore, it not only has the advantage that camber control in response to bumps and rebounds can be easily performed with the elastic deformation of one elastic bushing 14, but also has the advantage that camber control in response to bumps and rebounds is easily carried out by the elastic deformation of one elastic bushing 14. It has the advantage of increasing rigidity and reducing weight.

Furthermore, since the camber change can be controlled in response to bumps and rebounds, the position of the semi-trailing arm 1 and the direction of the swing center axis l can be freely selected so as not to interfere with the vehicle body. The degree of freedom in designing the pension can be increased.

Further, in the above embodiment, the second control link 32 of the camber control link mechanism 3 is
The fact that the second control link 32 is arranged in the vertical direction and its rotational center point P on the vehicle body side is set above the connection point Q with the first control link 31 is compatible with the relatively short length of the second control link 32. As a result, the mounting point of the camber control link mechanism 3 on the vehicle body side can be raised, which is advantageous in terms of the layout of the rear suspension, and the load acting on the second control link 32 is in the tensile direction, which is advantageous in terms of strength.

In addition, in the above embodiment, the base end of the first control link 31 is fixed near the rear wheel support part 121 (control link fixing part 123) of the semi-trailing arm 1, and one end of the lateral link 2 is By connecting the semi-trailing arm 1 near the control link fixing part 123 (lateral link attachment part 124), the length of the semi-trailing arm 1 torsioned by the camber control link mechanism 3 and the lateral link 2 can be reduced. By making it shorter, it is effective in improving torsional rigidity and reducing weight accordingly.

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.
Of course, the present invention can also be applied to a semi-trailing arm type or a full trailing arm type having two attachment points on the vehicle body side. Particularly in the case of a full trailing arm type, it is effective for negative camber control of the rear wheel during cornering.

Further, in the above embodiment, the second control link 32 of the camber control link mechanism 3 is arranged in the vertical direction, and the second control link 32 of the camber control link mechanism 3 is arranged in the vertical direction.
the lower end of the first control link 31,
Although the upper end of the second control link 32 is rotatably connected to the vehicle body, the upper end of the second control link 32 may be rotatably connected to the tip of the first control link 31, and the lower end of the second control link 32 may be rotatably connected to the vehicle body. In short, the second control link 32 is such that its rotation center point P on the vehicle body side is offset by a set amount with respect to the swing center axis l of the semi-trailing arm 1, and
The connection point Q with the control link 31 is located within a horizontal plane H including the swing center axis l of the semi-trailing arm 1 during setting, and is offset by a predetermined amount in the longitudinal direction of the vehicle body with respect to the swing center axis l. All you have to do is set it up.

[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 the inside of the vehicle body, and FIG. 5 is a diagram showing the rotation locus of the connection point between the first control link and the second control link. DESCRIPTION OF SYMBOLS 1... Semi-trailing arm, 2... Lateral link, 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...second control link rotation center point on the vehicle body side, Q...connection point, H
...Horizontal surface.

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 as to be able to swing vertically, and whose one end is located further inside the vehicle than the mounting point of the trailing arm on the vehicle body side. a lateral link whose other end is rotatably connected to the vehicle body at one position and the other end of the trailing arm near the rear hole support portion of the trailing arm through a ball joint; and a first lateral link whose base end is fixed to the trailing arm. a control link; 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, and the second control link includes:
It 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, and the connection point with the first control link is located at the center of the trailing arm during setting. 1. A rear suspension for an automobile, wherein the rear suspension is located in a horizontal plane that includes a pivot axis of the trailing arm and is offset by a predetermined amount in the longitudinal direction of the vehicle with respect to the pivot axis of the trailing arm.