JPS6143206B2 - - Google Patents

Description

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

Generally, when a vehicle is equipped with a rear suspension equipped with a vehicle, when the vehicle turns, a force (lateral force) toward the center of the turn acts on the left and right wheels, especially the wheels on the outside of the center of the turn. On the other hand, it is known that changing the toe-in so that the wheels face inward with respect to the driving direction is preferable in order to prevent oversteering and improve driving 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 It is connected to the flow at least in two places, front and back, and this connection structure is connected to the front spring.
Connected at the rear with a pin (West German patent no.
(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 systems, the lateral force is simply caused by displacement of the spring or rubber bushing in the toe-in direction, so the toe-in effect against the lateral force cannot be effectively exerted. Moreover, toe-in effects cannot naturally be expected for wheel acting forces other than lateral forces, such as braking force, engine braking force (so-called 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 float coupling and setting the position of each coupling part appropriately with respect to the center of the wheel, it is possible to reliably toe-in the wheel against lateral force, and to prevent other wheel-acting forces other than 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 first aspect of the present invention includes a rear suspension component whose one end is rotatably supported on the vehicle body, a wheel support member rotatably supports a wheel, and the wheel support member. a ball joint that swings freely around one point between the rear suspension component and the rear suspension component;
a first elastic bushing that connects the wheel support member and the rear suspension component; and a second elastic bush that connects the wheel support member and the rear suspension component; The 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, and the first elastic bushing is located in the first quadrant of the coordinates, and its axis is oriented within the rear of the vehicle. The second elastic bushing is located in the second quadrant of the coordinates, and the axis is arranged to face inward toward the rear of the vehicle body, and the first elastic bushing
The second elastic body bushing and the ball joint are arranged so that the plane including the three parts is located on the vertical plane including the wheel center axis, on the outer side of the vehicle body than the wheel center on the wheel center axis, and on the ground contact surface on the outside of the vehicle body. It is characterized by the presence of
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.

Furthermore, in addition to the above configuration, a second aspect of the present invention provides a stopper for preventing rearward movement of the wheel on at least one of the first elastic bushing and the second elastic bushing, thereby reducing the engine braking force. This ensures that toe-in changes can be made.

In addition, a third invention of the present invention provides, in addition to the configuration of the first invention, a stopper for preventing backward movement of the wheel is provided on the first elastic bushing, and
By providing the second elastic bushing with a stopper that prevents the wheel from moving outward, toe-in changes can be made effectively and reliably in response to the various wheel acting forces.

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 railing arm 1, that is, a forked front end, is rotatably supported by a subframe 2, which is a vehicle body component and is 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 gear 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.

Further, FIG. 2 shows a second embodiment in which the present invention is applied to a strut-type rear suspension, in which reference numeral 10 denotes a strut hub as a rear suspension component that supports struts 11, and the strut hub 10 extends in the left-right direction of the vehicle body. Through two-link suspension arms 12, 12 extending to
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 denotes a leaf spring that extends in the longitudinal direction of the vehicle body and carries the axle tube 20, and its front end is rotatably connected to the vehicle body through an eye 26 and rear end through a shackle 27. ing. 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 (Y 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 second 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 inside of the vehicle body, and the second elastic bushing _R2 is
Contrary to the elastic bush _R1 , it is arranged so that its axis is inclined toward the rear and outside of the vehicle body. In addition, in FIG. 4, the coordinates (X,
For Y), set the horizontal Y-axis in the left and right direction based on the wheel center O, and create a rectangular coordinate system (X, Y, Z).
The coordinate system (L, M, 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 ₁ 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 negative (-) amount (i.e. outside the vehicle body)
and is arranged so that G is a negative (-) amount (outside the vehicle body).

The fact that both W and G are negative (-) amounts (that is, outside the vehicle body) is an optimal arrangement for an inboard type brake device in which the brake device is located inside the vehicle body near the differential.

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 △P, R ₁ , 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 inward direction orthogonal to the axis, or the second
The rigidity of the elastic bushing _R2 in the outward direction orthogonal to the axis is made higher than other parts of the wheel 4.
If a stopper is provided to prevent movement of (15, 23) in the toe-out direction, the above-mentioned toe-in change can be easily and reliably performed.

Since the brake force B acts on the wheel grounding point in the +X direction, the (-) amount of G rotates the mounting surface Q counterclockwise around the ball joint P around the M axis or L axis, respectively. Acts as a moment force. In this case, in the case of a moment force in the counterclockwise direction around the L axis, the mounting surface Q is rotationally displaced in the toe-in direction, and the wheels 4 (15, 23) change in toe-in, as in the case of the above-mentioned lateral force S. In addition, in the case of a moment force in the counterclockwise direction around the M-axis, the axis of the first elastic bushing _R1 is directed inward to the rear of the vehicle, that is, outward to the front of the vehicle, and the axis of the second elastic bushing _R2 is are arranged outward toward the rear of the vehicle body, that is, outward toward the front of the vehicle body.In general, the stiffness of an elastic bushing is lower in the axial direction than in the direction orthogonal to the axial center, and it is easier to elastically deform in the axial direction. Due to this characteristic, the mounting surface Q is rotationally displaced about P in the toe-in direction, and the wheels 4 (15, 23) change in toe-in, so that a toe-in effect is obtained in either case.

Engine braking force E acts on the wheel center O in the +X direction, so depending on the (-) amount of W, it acts as a moment force that rotates the mounting surface Q approximately counterclockwise around the L axis around P. As a result, as in the case of the lateral force S, the mounting surface Q is rotationally displaced about P in the toe-in direction, and the wheels 4 (15, 23) change in toe-in. At that time, the engine braking force E
A stopper is installed to prevent backward movement of the wheels 4 (15, 23) so that the first elastic bushing _R1 does not displace inward to the vehicle interior, which would impede the toe-in effect, due to the moment force in the clockwise direction around the M-axis. It is preferable to provide it at the rear end of the bush _R1 . In addition, instead of this, a wheel 4 (15, 23) is attached to the rear end of the second elastic bushing _R2 to prevent the bushing _R2 from displacing outward from the vehicle body.
Of course, a stopper may be provided to prevent rearward movement of the bushes R ₁ and R ₂ .

Since the engine driving force K acts on the wheel center O in the -X direction, the (-) amount of W and the (-) amount of G move the mounting surface Q approximately counterclockwise around the M axis with P as the center. By acting as a moment force to rotate in the direction, at the same time as the above brake force B around the M axis,
The mounting surface is rotationally displaced about P in the toe-in direction, and the wheels 4 (15, 23) change in toe-in. In this case, the wheel 4 (15, 23) tries to move in the toe-out direction around the L axis due to the engine driving force, but the rigidity in the outward direction perpendicular to the axis of the second elastic body bush _R2 By making it higher than other parts, movement in the toe-out direction can be prevented.

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 the wheel center O reference (X, Z) as seen from the left side of the vehicle body, and the wheel hub 3 ) is float-coupled by a ball joint P located in the fourth quadrant, a first elastic bush R ₁ located in the first quadrant, and a second elastic bush R ₂ located in the second quadrant. Further, as described above, the first elastic bushing _R1 has its axis facing inward toward the rear of the vehicle, and the second elastic bushing _R2 has its axis facing outward from the rear of the vehicle. , the surface including the first and second elastic bushes R ₁ and R ₂ (mounting surface Q) is aligned with the wheel center axis (Y
wheel center axis (Y axis)
Above, the outside of the vehicle body from the wheel center O (W<
O), and is arranged so as to be located on the outside of the vehicle body (G<O) on the ground contact surface.

As shown in detail in FIG. 8, the ball joint P includes a casing 32 provided at the tip of a first arm portion 31 that protrudes from the wheel hub 3 in the fourth quadrant direction and has a spherical inner surface 32a; The semi-trailing arm 1 is rotatably supported by a bracket 33 having a U-shaped cross section, and includes a support shaft 34 having a spherical portion 34a in the center that is rotatably fitted into the casing 32. By freely rotating the casing 32 about the spherical portion 34a, the semi-trailing arm 1 and the wheel hub 3 are swingably connected about one point (the center of the spherical portion 34a). .

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. An outer cylinder 39 is fitted onto the inner cylinder 37 fixed to the tip of the inner cylinder 38 and has a shorter axial length than the inner cylinder 37, and rubber is filled and fixed between the outer cylinder 39 and the inner cylinder 37. The semi-trailing arm 1 is configured to rotatably connect the semi-trailing arm 1 and the wheel hub 3. Further, between the outer cylinder 39 on the rear side in the axial direction (on the left side in FIG. 9) and one side wall 35a of the bracket 35, there is a stopper made of hard rubber, hard synthetic resin, etc. that is more rigid than the rubber 40. Since the member 41 is interposed and prevents the outer cylinder 39 (that is, the wheel 4) from moving backward,
When the engine braking force E is applied, the stopper is configured to suppress rearward inward elastic deformation of the bush _R1 and prevent rotation of the mounting surface Q around the M axis. Toe-in changes around the axis 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 first 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. The semi-trailing arm 1 includes a rubber 47 made of rubber or the like filled and fixed between the
and the wheel hub 3 are rotatably coupled to each other. Further, a portion 47a perpendicular to the axial direction of the rubber 47 and extending 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 48 is configured to prevent the outward movement of the wheel 4 by suppressing the elastic deformation in the outward direction orthogonal to _{the axial direction of the bushing R 2 .} Ensure directional displacement,
Toe-in changes can be made reliably.

Therefore, the above ball joint P
Due to the arrangement structure of the first and second elastic body bushes R ₁ and R ₂ , the mounting surface Q is Ball joint P
The wheel 4 (15,
23) Toe-in change can be performed reliably,
Therefore, oversteering can be prevented and the running stability of the vehicle can be significantly improved.

In this case, the first elastic bushing R ₁ and the second
By providing a stopper on at least one of the elastic bushes _R2 to prevent rearward movement of the wheels 4 (15, 23), the toe-in change relative to the engine braking force E can be performed more reliably. In addition, the wheel 4 ( ₁
5, 23) to prevent outward movement of the stopper 4.
8, or by providing a stopper on the first elastic bushing _R1 to prevent the wheels 4 (15, 23) from moving inward, and preventing the wheels 4 (15, 23) from moving in the toe-out direction, the lateral force can be reduced. It is possible to reliably change the toe-in for S.
In particular, as shown in FIGS. 9 to 12 above, the first elastic bushing _R1 is provided with a stopper that prevents the wheel from moving backwards, and the second elastic bushing _R2 is provided with a stopper that prevents the wheel from moving outward. If so, the toe-in change described above can be effectively ensured.

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 For B, only an acting force acting on each of the bushes R ₁ and R ₂ is applied at a lever ratio of approximately 1:1;
Compared to a case where 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 acting force is about half as small as that of the case where 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 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 structure 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-mentioned embodiments, but also includes various other modifications. For example, in the above embodiment, the present invention is applied to semi-trailing type, strut type, and deion type rear suspensions, but the present invention is also applicable to various double ring type rear suspensions such as the Witsubon type or various swing arm type rear suspensions. It can also be applied. For example, in the case of the Utsushu Bon type, the connecting hub that connects the 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 and the wheel support member are connected to the ball joint P.
and the first and 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 of the horizontal-vertical coordinates based on the wheel center when viewed from the left side of the vehicle. located in the first and second quadrants, respectively;
The directions of the axes of the respective axes are inward toward the rear of the vehicle body and outward toward the rear of the vehicle body, respectively, and the plane including the above three connection points is located on the vertical plane including the wheel center axis, and on the wheel center axis, the plane is located outside the vehicle body from the wheel center. In addition, the wheels are placed on the outside of the vehicle body on the ground contact surface, making it possible to reliably change the toe-in of the wheels in response to various wheel acting forces such as braking force and engine driving force, improving vehicle running stability and improving the rear suspension structure. This greatly contributes to simplification.

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

In addition, by providing a stopper for preventing rearward movement of the wheel on at least one of the first and second elastic bushings, it is possible to ensure a change in toe-in relative to the engine braking force.

Furthermore, by providing a stopper for preventing rearward movement of the wheel on the first elastic bushing and a stopper for preventing outward movement of the wheel on the second elastic bushing, toe-in changes due to the various wheel acting forces are suppressed. This can be done effectively and reliably.

[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;
Fig. 7 is a rear view of the vehicle seen from the rear, Fig. 8 is an enlarged sectional view taken along the - line in Fig. 7, Fig. 9 is an enlarged sectional view taken along the - line in Fig. 5, and Fig. 10 is an enlarged sectional view taken along the - line in Fig. 5. Figure 11 is the XI of Figure 6.
12 is an enlarged cross-sectional view taken along line XI. FIG. 12 is a cross-sectional view taken along line XII--XII of FIG. 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)

[Scope of 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 connection between the wheel support member and the rear suspension component. a ball joint that connects the wheel support member and the rear suspension component so as to be swingable about one point; a first elastic bush that connects the wheel support member and the rear suspension component; and a first elastic bush that connects the wheel support member and the rear suspension component. 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, and the first elastic bush The second elastic bushing is located in the second quadrant of the above coordinates, and the axis is located inward toward the rear of the vehicle body. Further, the first elastic bushing, the second elastic bushing, and the ball joint are arranged such that the plane including the three is located on the wheel center axis in a vertical plane including the wheel center axis, and is located on the outer side of the vehicle body from the wheel center. , a rear suspension characterized by being located on the outside of the vehicle body on the ground contact surface. 2. 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 seen from the left side of the vehicle body, and the first elastic body bushing is located in the first quadrant of the coordinates. The second elastic bushing is located in the second quadrant of the coordinates, and the second elastic bushing is arranged so that the axis is directed inward toward the rear of the vehicle body. In addition, the first elastic bushing, the second elastic bushing, and the ball joint are located on the outside of the vehicle body from the wheel center on the wheel center axis in a vertical plane including the wheel center axis, and on the ground contact surface of the vehicle body. A rear suspension, which is disposed on the outside, and further includes a stopper provided on at least one of the first elastic bushing and the second elastic bushing for preventing rearward movement of the wheel. Shion. 3. 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 seen from the left side of the vehicle body, and the first elastic body bushing is located in the first quadrant of the coordinates. The second elastic bushing is located in the second quadrant of the coordinates, and the second elastic bushing is arranged so that the axis is directed outward toward the rear of the vehicle. In addition, the first elastic bushing, the second elastic bushing, and the ball joint are located on the outside of the vehicle body from the wheel center on the wheel center axis in a vertical plane including the wheel center axis, and on the ground contact surface of the vehicle body. The first elastic bushing is further provided with a stopper for preventing rearward movement of the wheel, and the second elastic bushing is provided with a stopper for preventing outward movement of the wheel. The rear suspension is characterized by a stopper that allows the rear suspension to move.