JPS6143205B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rear suspension installed on a vehicle, and more particularly to a rear suspension that changes the toe-in of a wheel in response to various wheel acting forces such as lateral force.

In general, when a vehicle is turning with a rear suspension installed on a vehicle, a force acting toward the turning center acts on the left and right wheels and the wheels on the outside of the turning center. It is known that changing the toe-in of the wheel so that it points inward with respect to the running direction in response to a force is preferable in order to prevent oversteering and improve running stability.

Conventionally, as a rear suspension that changes the toe-in of the wheel in response to such lateral force, the rear suspension arm, which has one end rotatably supported on the vehicle body, and the wheel hub, which rotatably supports the wheel, have a A float connection is made at least at two points in the front and back, and this connection structure is connected with a spring at the front and a pin at the rear (West German Patent No.
2158931), the characteristics of the front spring are gradually weakened according to the lateral force (West German Patent No. 2355954), or the front and rear springs are connected with rubber bushings, and the stiffness of the front rubber bushing is reduced to the rear. Rubber bushings made softer than those of
52-37649) is proposed.

However, in all of the above-mentioned conventional devices, the toe-in effect against the lateral force cannot be effectively exerted because the lateral force is simply displaced in the toe-in direction of the spring or the rubber bushing. Moreover, the wheel acting force other than the lateral force,
For example, toe-in effects cannot be expected with respect to brake force, engine braking force, and engine driving force.

In view of this, the present invention provides a ball joint and two elastic bushes to connect the rear suspension component such as the rear suspension arm and the wheel support member that rotatably supports the wheel. By using a float connection and appropriately setting the position of each connection with respect to the center of the wheel, it is possible to reliably change the toe-in of the wheel in response to lateral force, and it is also possible to change the toe-in of the wheel in response to lateral force. In other words, the object is to be able to change toe-in also with respect to brake force, engine braking force, and engine driving force.

In order to achieve this object, the present invention has a configuration including a rear suspension component whose one end is rotatably supported on the vehicle body, a wheel support member rotatably supports a wheel, and a rear suspension component that rotatably supports the wheel. a ball joint that connects the component member so as to be able to swing around one point; a first elastic bushing that connects the wheel support member and the rear suspension component; and the wheel support member and the rear suspension component member. a second elastic bushing that connects the rear suspension component to the rear suspension component; The elastic bushing is located at the first point of the above coordinates.
The second elastic bushing is located in the second quadrant of the coordinates and is arranged so that its axis faces outward toward the rear of the vehicle body, and the second elastic bushing is located in the second quadrant of the coordinates and its axis faces toward the rear of the vehicle body. placed,
Further, the first elastic bushing, the second elastic bushing, and the ball joint are arranged so that, in a vertical plane including the wheel center axis, the first elastic bush, the second elastic bush, and the ball joint are on the inside of the vehicle body from the wheel center on the wheel center axis, and on the outside of the vehicle body on the ground contact surface. It is characterized by being arranged so that it is located at. As a result, the mounting surface including the three connection points mentioned above is rotated in the toe-in direction around the ball joint in response to lateral force, brake force, engine braking force, and engine driving force, and the wheel changes toe-in. This is what I did.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 shows a first embodiment in which the present invention is applied to a semi-trailing type rear suspension. Reference numeral 1 denotes a semi-trailing arm as a component of the rear suspension extending substantially in the longitudinal direction of the vehicle body; One end of the trailing arm 1, that is, a forked front end, is rotatably supported by a subframe 2 as a vehicle body component disposed in the left-right direction of the vehicle body. Reference numeral 3 denotes a wheel hub as a wheel support member that rotatably supports the wheel 4. The wheel 4 is connected to the other end of a drive shaft 6 whose one end is connected to a differential 5. In addition, in FIG. 1, 7 is a shock absorber, 8 is a coil spring, and 9 is a stabilizer.

There is a gap between the wheel hub 3 and the semi-trailing arm 1 as shown in FIG.
It is float-coupled by a ball joint P that is swingable about a point, and two first and second elastic bushings _R1 and _R2 made of rubber bushings or the like. The arrangement structure of the ball joint P and the first and second elastic bushes R ₁ and R ₂ will be described later.

FIG. 2 shows a second embodiment in which the present invention is applied to a strut-type rear suspension, and 10 is a strut hub as a rear suspension component that supports a strut 11. Through two-link suspension arms 12, 12 extending in the direction,
It is rotatably supported by sub-frames 13 and 14, which serve as vehicle body structural members, which are arranged front and rear in the left-right direction of the vehicle body. Between the strut hub 10 and the wheel hub 16, which is a wheel support member that rotatably supports the wheel 15, there is a ball joint P and the first and second
They are connected by elastic bushes R ₁ and R ₂ . In FIG. 2, 17 is a stabilizer, 18 is a differential, and 19 is a drive shaft.

Furthermore, FIG. 3 shows a third embodiment in which the present invention is applied to a Deion type rear suspension,
is a rear axle tube as a rear suspension component extending in the left-right direction of the vehicle body and into which a rear axle provided separately from the drive shaft 21 is inserted; It is rotatably supported by the vehicle body via tension rods 22, 22. Similarly, a ball joint P and first and second elastic bushings are connected between the end of the rear axle tube 20 and the wheel hub 24, which is a wheel support member that rotatably supports the wheel 23.
It is connected by R ₁ and R ₂ . In FIG. 3, reference numeral 25 extends in the longitudinal direction of the vehicle body and represents the rear axle pipe 20.
The front end is rotatably connected to the vehicle body through the eye 26 and the rear end through the shaft 2, respectively. Further, 28 is a differential.

The ball joint P and the first and second elastic bushings in the first to third embodiments are
The arrangement structure of R ₁ and R ₂ will be explained with reference to FIG.

Figure 4 shows wheel 4 (or 1) on the rear right side of the vehicle body.
5, 23) as seen from the left side (inside) of the vehicle body, and in the horizontal (X axis)-vertical (Z axis) coordinates of the wheel center O standard as seen from the left side of the vehicle body.
The ball joint P is located in the fourth quadrant, the first elastic bush R ₁ is located in the first quadrant, and the first elastic bush R ₂ is located in the second quadrant.

Further, the first elastic bushing _R1 is arranged so that its axis is inclined toward the rear and outside of the vehicle body, and the second elastic bushing _R2 is
Contrary to the elastic bushing _R1 , it is arranged so that its axis is inclined toward the rear and inside of the vehicle body. In addition, in FIG. 4, the above coordinates (X,
Z), set the Y-axis in the horizontal left and right direction based on the wheel center O, and create a rectangular coordinate system (X, Y, Z).
The coordinate system (L, Y, N) is a coordinate system whose origin is the center of the ball joint P, which is obtained by moving the above coordinate system in parallel.

Furthermore, each attachment point of the ball joint P, the first elastic bush R ₂ and the second elastic bush R ₂ (in the case of the ball joint P, the center thereof,
In the case of the first and second elastic bushes R ₁ and R ₂ , the triangular mounting surface Q including the central point of each axis
is the intersection line q with the YZ plane of the above coordinate system (X, Y, Z) in the vertical plane containing the wheel center axis
Let W be the offset amount from the wheel center O on the wheel center axis (Y axis), G be the offset amount on the wheel contact surface, and let the offset toward the inside of the vehicle body be plus (+).
The above W is a positive (+) amount (that is, inside the car body),
It is arranged so that G is a negative (-) amount (outside the vehicle body).

Next, to explain its effect, since the lateral force S acts in the +Y direction with respect to the wheel grounding point, the mounting surface Q of the above ΔP, R ₁ and R ₂
By acting as a moment force to rotate counterclockwise approximately around the L axis around the ball joint P, the mounting surface Q is rotationally displaced around the L axis around P in the toe-in direction, and the wheel 4 (15, 23) will change toe-in. At this time _, a force directed outward from the vehicle body is generated in the first elastic bush _R1 , and a force directed toward the vehicle body is generated in the second elastic bush _R2 . stiffness in the outward direction orthogonal to the axis, or the second
By making the rigidity of the elastic bush _R2 in the inward direction orthogonal to the axis lower than that of other parts, the toe-in change described above can be easily and reliably performed.

Brake force B acts in the +X direction with respect to the wheel grounding point, so depending on the (-) amount of G, the mounting surface Q is approximately L centered on the ball joint P.
By acting as a moment force that rotates counterclockwise around the axis, the above mounting surface Q becomes P
The wheel 4 (15, 23) is rotationally displaced in the toe-in direction about , and the wheel 4 (15, 23) changes in toe-in. At this time, in order to prevent the first elastic body bushing _R1 from being displaced inward of the vehicle body which impedes the toe-in effect due to the moment force in the counterclockwise direction around the M axis caused by the brake force B, the first elastic body It is preferable to provide a stopper at the front end of the bush _R1 in order to ensure toe-in change.

Engine braking force E acts on the wheel center O in the +Y direction, so depending on the (+) amount of W and the (-) amount of G, the mounting surface Q is moved approximately clockwise around the M axis with P as the center. Acts as a moment force that causes rotation. At that time, the axis of the first elastic bushing _R1 is directed outward toward the rear of the vehicle, and the second
The axial center of the elastic bushing _R2 is located toward the rear and inward of the vehicle body, and the rigidity of the elastic bushing is generally lower in the axial direction than in the direction perpendicular to the axial center, so that it deforms elastically in the axial direction. Since the mounting surface Q rotates around P in the toe-in direction, the wheel 4 (1
5, 23) toe-in changes will be performed.

Since the engine driving force K acts on the wheel center O in the -X direction, the (+) amount of W acts as a moment force that rotates the mounting surface Q approximately counterclockwise around the L axis around P. As a result, the mounting surface Q is rotationally displaced in the toe-in direction about P, as in the case of the above-mentioned brake force B, and the wheel 4 (15, 23)
The toe-in will change. Also in this case, it is preferable to provide a stopper at the front end of the first elastic bushing _R1 .

Next, the specific structure of the first embodiment (semi-trailing type rear suspension) will be explained with reference to FIGS. 5 to 7. The front end has a rubber bush 3.
The rear end of the semi-trailing arm 1, which is rotatably supported on the vehicle body (side frame 2) via 0 and 30, and the wheel hub 3, which rotatably supports the spindle 4a of the wheel 4, are located on the left side of the vehicle body. The fourth coordinate (X, Z) of the wheel center O' reference as seen from
They are float-coupled by a ball joint P located in the quadrant, a first elastic bushing _R1 located in the first quadrant, and a second elastic bushing _R2 located in the second quadrant. Further, as described above, the first elastic bushing R ₁ is arranged with its axis facing outward toward the rear of the vehicle body, and the axis of the second elastic bushing R ₂ is disposed with its axis facing inward toward the rear of the vehicle body, and the ball joint P , first and second elastic bushings R ₁ ,
On the wheel center axis (Y axis), the surface including the three parts of R ₂ (mounting surface Q) is a vertical plane including the wheel center axis (Y axis), and the ground contact surface is on the inside of the vehicle body (W>O) from the wheel center O. Above is the outside of the car body (G<O)
It is located so that it is located at

As shown in detail in FIG. 8, the ball joint P is connected to a casing 32 provided at the tip of a first arm portion 31 protruding from the wheel 3 in the fourth quadrant direction, and a semi-trailing arm 1. It consists of a support shaft 34 which is supported via a bracket 33 having a U-shaped cross section and has a spherical part 34a in the center that is rotatably fitted into the casing 32,
The casing 32 freely rotates around the spherical part 34a, so that the semi-trailing arm 1 and the wheel hub 3 are swingably connected around one point (the center of the spherical part 34a). has been done.

Further, the first elastic bushing _R1 is made of a rubber bushing, and as shown in detail in FIGS. axis 36
, an inner cylinder 37 rotatably fitted to the support shaft 36 and interposed between the side walls 35a, 35a of the bracket 35, and a second arm portion protruding from the wheel hub 3 in the first quadrant direction. 38, an outer cylinder 39 that is fitted onto the inner cylinder 3 and has a shorter axial length than the inner cylinder 37, and the outer cylinder 39 and the inner cylinder 3.
A rubber 40 made of rubber or the like is filled and fixed between the semi-trailing arm 1 and the wheel hub 3, and is configured to rotatably connect the semi-trailing arm 1 and the wheel hub 3. Further, between the outer cylinder 39 on the front side in the axial direction (on the right side in FIG. 9) and one side wall 35a of the bracket 35, a stopper member made of hard rubber, hard synthetic resin, etc. that is more rigid than the rubber 40 is provided. 41 is interposed, and by restricting the forward movement of the outer cylinder 39, when the brake force B and the engine driving force K are applied, elastic deformation of the bush _R1 in the forward inward direction is suppressed, and the mounting surface Q Rotation around the M axis of the mounting surface Q is prevented from occurring, and toe-in changes around the L axis of the mounting surface Q are ensured.

Furthermore, the second elastic bushing _R2 is made of a rubber bushing, and as shown in detail in FIGS. A shaft 43, an inner cylinder 44 rotatably fitted to the support shaft 43 and interposed between the side walls 42a, 42a of the bracket 42, and a second cylinder 44 from the wheel hub 3.
An outer cylinder 46 is fixed to the tip of the third arm part 45 projecting in the quadrant direction, is fitted onto the inner cylinder 44, and has a shorter axial length than the inner cylinder 44; and the outer cylinder 46 and the inner cylinder 44. A rubber 47 made of rubber or the like is filled and fixed between the semi-trailing arm 1 and the wheel hub 3, and is configured to rotatably connect the semi-trailing arm 1 and the wheel hub 3. Furthermore, a portion of the rubber 47 that is perpendicular to the axial direction and extends toward the outside of the vehicle body (lower side in FIG. 12) is made of hard rubber, hard synthetic resin, etc., which has higher rigidity than other portions, and the bushing is
A stopper portion 48 is configured to restrict the elastic deformation in the outward direction orthogonal to the axial direction of the bushing R ₂ , and thus facilitates the displacement of the bushing R ₂ toward the vehicle interior when a lateral force S is applied, thereby facilitating toe-in. Makes it easy to make changes.

Therefore, the above ball joint P
Due to the arrangement structure of the first and second elastic bushes R ₁ and R ₂ , the mounting surface Q is able to resist the ball joint P against various wheel acting forces such as lateral force S, braking force B, and engine braking force E. By rotationally displacing the wheel 4 (15, 23) around the center, the wheel 4 (15, 23) can be changed reliably, thereby preventing oversteering and significantly improving the running stability of the vehicle.

Moreover, the first and second elastic bushes R ₁ ,
R ₂ is located in the first and second quadrants above the wheel center O, and the ball joint P, which is the center of rotation, is in the fourth quadrant below the wheel center O, so the lateral force S and the braking force are With respect to B, an acting force acting on each of the bushes R ₁ and R ₂ at a lever ratio of approximately 1:1 only acts,
Since the acting force is about half smaller than when the rotation center P is above the wheel center O and the bushes R ₁ and _{R 2 are} below _the wheel center O, the The strength design is not difficult and easy, and the durability can be increased.

Furthermore, if the center of rotation P is in the fourth quadrant, the lateral force S
Since the distance in the vertical direction from the point of application (grounding point) of the brake force B is relatively short, the wheel 4 (15, 23) in response to the lateral force S and the brake force B
Since there is little movement deviation and the behavior in the toe-in direction can be performed stably, the toe-in effect can be further ensured.

In addition, the toe-in effect can be obtained against the various wheel acting forces by the simple structure of the float connection by combining the ball joint P and the first and second elastic bushes R ₁ and R ₂ .
The rear suspension configuration can be significantly simplified compared to the case where a toe-in mechanism is provided for each acting force.

It should be noted that the present invention is not limited to the above embodiments, but includes various other modifications. For example, in the above embodiment, an example is shown in which the invention is applied to a semi-trailing type, a strut type, and a deion type rear suspension. It can also be applied to For example, in the case of the Uitshubon type, a connecting hub that connects two upper and lower arms extending in the left-right direction of the vehicle constitutes the rear suspension component in the present invention, and the connecting hub, the wheel support member, the ball joint P, and the first and the second elastic bushings R ₁ and R ₂ .

Moreover, although the right wheel at the rear of the vehicle body has been described in FIGS. 4 to 7, it goes without saying that the same can be said for the left wheel at the rear of the vehicle body.

As explained above, according to the present invention, the ball joint and the first and The ball joint is float-coupled with the second two elastic bushings, and the ball joint is located in the fourth quadrant in the horizontal-vertical coordinates of the wheel center reference when viewed from the left side of the vehicle body, and the first and second elastic bushings are connected to each other. located in the first and second quadrants, respectively;
The directions of the respective axes are arranged outward toward the rear of the vehicle body and toward toward the rear rearward of the vehicle body, respectively, and the plane containing the three connection points mentioned above is positioned inward of the vehicle body from the wheel center on the wheel center axis in a vertical plane including the wheel center axis. In addition, due to the simple structure of placing it on the outside of the vehicle body on the ground contact surface, lateral force, braking force,
The toe-in of the wheels can be changed in response to various wheel acting forces such as engine braking force and engine driving force, which greatly contributes to improving the running stability of the vehicle and simplifying the rear suspension configuration.

Furthermore, in response to wheel acting forces such as lateral forces, the ball joint located in the fourth quadrant in the coordinates based on the wheel center is rotated and displaced, so each elastic body in the first and second quadrants responds to lateral forces, etc. The acting force on the bushing is small, which improves its durability, and the wheel is less likely to shift due to the acting force, resulting in excellent behavior stability in the toe-in direction, making the toe-in effect more reliable. It has the advantage of being able to

[Brief explanation of the drawing]

The drawings illustrate embodiments of the invention, FIG.
FIG. 2 is a schematic perspective view showing the second embodiment. FIG. 3 is a schematic perspective view showing the third embodiment. FIG. 4 is a ball joint and the first and second elastics. 5 is a detailed plan view showing the specific structure of the first embodiment; FIG. 6 is a side view of the vehicle body as seen from the right side;
Figure 7 is a rear view of the body seen from the rear, Figure 8 is a rear view of the body.
An enlarged sectional view taken along the - line in the figure, Figure 9 is the 5th section.
Figure 10 is an enlarged cross-sectional view taken along line - of Figure 9, Figure 11 is a cross-sectional view taken along line -XI of Figure 6.
An enlarged sectional view taken along the XI line, Figure 12 is the same as Figure 11.
It is a sectional view taken along the line XII-XII. 1...Semi-trailing arm, 2...Subframe, 3...Wheel hub, 4...Wheel,
10...Strut hub, 12...Suspension arm, 13, 14...Subframe, 15...
... Wheel, 16 ... Wheel hub, 20 ... Rear axle tube, 22 ... Tension rod, 23 ... Wheel, 24 ... Wheel hub, P ... Ball joint, R ₁ ... First elastic bushing, R ₂ ...
Second elastic body bush, O...Wheel center.

Claims (1)

[Claims] 1. A rear suspension component whose one end is rotatably supported on the vehicle body, a wheel support member which rotatably supports a wheel, and a rocking mechanism between the wheel support member and the rear suspension component about one point. A ball joint movably coupled, a first elastic bushing coupling between the wheel support member and the rear suspension component, and a first elastic bushing coupling the wheel support member and the rear suspension component. 2 elastic body bushings, the ball joint is located in the fourth quadrant of the horizontal-vertical coordinates based on the wheel center when viewed from the left side of the vehicle body, and the first elastic body bushing is located in the first quadrant of the coordinates. and the second elastic bushing is located in the second quadrant of the coordinates and is arranged so that the axis is oriented toward the rear of the vehicle; Further, the first elastic bushing, the second elastic bushing, and the ball joint are arranged so that, in a vertical plane including the wheel center axis, the first elastic bush, the second elastic bush, and the ball joint are on the inside of the vehicle body from the wheel center on the wheel center axis, and on the outside of the vehicle body on the ground contact surface. A rear suspension characterized by being positioned so that it is located at.