JPS6143202B2 - - 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 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 it is preferable to change the toe-in so that the wheels face inward with respect to the driving direction 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 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.
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 bushings is reduced. One that is softer than the rubber bushing on the side (Tokukosho)
No. 52-37649) has been 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 driving force.

In view of this, the present invention provides a float connection between a rear suspension component such as the rear suspension arm and a wheel hub using a ball joint and two elastic bushes, and each connection portion The main objective is to enable the toe-in of the wheel to be effectively changed in response to lateral force by appropriately setting the position of the wheel with respect to the center of the wheel.

Furthermore, another object of the present invention is to enable the toe-in effect to be exerted on acting forces other than lateral force, that is, braking force, engine braking force, and engine driving force.

In order to achieve this object, the present invention has a configuration that includes a rear suspension component whose one end is rotatably supported on the vehicle body, a wheel hub that rotatably supports a wheel, and a rear suspension component that has one end rotatably supported on the vehicle body. a first ball joint that connects the wheel hub and the rear suspension component so as to be able to swing around a single point;
an elastic bushing and a second elastic bushing that connects the wheel hub and the rear suspension component; , the first elastic bushing and the second elastic bushing are located in two of the remaining quadrants excluding the quadrant in which the ball joint is located. In response to lateral force, the rotation of the mounting surface including the three connection points mentioned above is changed around the ball joint to change the toe-in of the wheel, and in response to other braking force, engine braking force, and engine driving force. The toe-in can also be changed by rotating the mounting surface.

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 in the longitudinal direction of the vehicle; One end of the ring 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. Further, 3 is a wheel hub that rotatably supports a wheel 4, and 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 Figure 1,
7 is a shock absorber, 8 is a coil spring, and 9 is a stabilizer.

Between the wheel hub 3 and the semi-trailing arm 1 is a ball joint P that is swingable about one point, as shown in FIGS. The first and second elastic bushings R 1 and R 2 are float-coupled by two first and second elastic bushings R ₁ and R ₂ made of rubber bushings or the like having a fixed axis. In addition, this ball joint P, the first elastic body bushing, and the second elastic body bushing
The arrangement structure of 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. 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. The strut hub 10 and wheel 1
Similarly to the first embodiment, the ball joint P and the wheel hub 16 that rotatably supports the wheel 5 are connected to each other by a ball joint P and first and second 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. The end of the rear axle tube 20 and the wheel hub 24 that rotatably supports the wheel 23 are similarly connected by a ball joint P and first and second elastic bushes R ₁ and R ₂ . has been done. In FIG. 3, reference numeral 25 denotes a leaf spring that extends in the longitudinal direction of the vehicle body and rides on the rear wheel pipe 20.
The front end is rotatably connected to the vehicle body through an eye 26 and the rear end through a shaft 27, 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 based on the wheel center O seen from the left side of the vehicle body.
The ball joint P is located in the fourth quadrant, and the first and second elastic bushings R ₁ and R ₂ are located in the first and second quadrants, respectively, of the remaining three quadrants.

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 opposite to the first elastic bushing _R1 . It is arranged so that its axis is inclined toward the rear and inside of the vehicle body. still,
In FIG. 4, a rectangular coordinate system (X, Y, Z) is constructed by setting the Y-axis in the horizontal left and right direction based on the wheel center O at the coordinates (X, Y) above.
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.

Therefore, each attachment point of the ball joint P, the first and second elastic bushes R ₁ , R ₂ (in the case of the ball joint P, the center, the first and second elastic bushes R ₁ , In the case of R ₂ , the wheel center O in the Y-axis direction is located at the intersection line q of the triangular mounting surface Q including the center point of each axis) and the YZ plane of the above coordinate system (X, Y, Z). The offset amount on the wheel contact surface is W, and the offset amount on the wheel contact surface is G.
and add (+) the amount in the inner direction of each wheel.
In terms of quantity, the above W is plus (+) as shown in Figure 4.
(a) Since the lateral force S acts on the wheel grounding point in the +Y direction, the above △
The mounting surface Q of PR ₁ R ₂ rotates approximately clockwise around the N axis around the ball joint P. At that time, since the ball joint P is located in the fourth quadrant and is offset backward from the line of action of the lateral force S, a moment about the L axis is generated, and this moment causes the ball joint P in the second quadrant to Each of the bushes R ₁ and R ₂ is elastically deformed so that the attachment point of the second elastic body bush R ₂ is displaced more toward the inside of the vehicle body than the attachment point of the first elastic body bush R ₁ in the first quadrant. The toe-in will change.

(b) Since the brake force B acts in the +X direction with respect to the wheel grounding point, the mounting surface Q will be approximately L with the ball joint P at the center due to the (-) amount of G in response to the brake force B. The wheel is rotated counterclockwise around the axis, and the toe-in of the wheel changes. At that time, the mounting surface Q further tries to rotate counterclockwise around the M axis around the ball joint P, so the first
The elastic bushing _R1 is displaced inward to the vehicle body, and the second elastic bushing _R2 in the second quadrant is displaced to the outside of the vehicle body.
It will be toe out. Therefore, counterclockwise rotation of the mounting surface Q around the M axis is prevented, and the first
In order to prevent the first elastic bushing R ₁ of the quadrant from being displaced inward of the vehicle body, which would impede the toe-in effect, it is preferable to provide a stopper at the front end of the bushing R ₁ .

(c) Since the engine braking force E acts in the +X direction with respect to the wheel center O, in response to the engine braking force E, the mounting surface Q is approximately clockwise around the M axis around the ball joint P. (toward the rear of the vehicle body). At this time, since the axis of the first elastic bush _R1 is inclined toward the rear outer side of the vehicle body, and the axis of the second elastic body bush _R2 is inclined toward the rear inner side of the vehicle body, the first elastic body bush
R ₁ is displaced to the outside of the vehicle body, and the second elastic bushing R ₂ is displaced to the inside of the vehicle body, resulting in a wheel toe-in change.

(d) The engine driving force K acts on the wheel center O in the -X direction, so for the engine driving force K, the mounting surface Q has a larger (+) amount of W than the ball joint P. The wheel is rotated counterclockwise around the L axis, and the wheel changes toe-in. At this time, a stopper may be provided at the front end of the first elastic bushing R 1 to prevent the first elastic bushing R ₁ from being displaced inward to the vehicle interior, which would impede the toe-in effect, as in the case where _the brake force B is applied. preferable.

In addition, when the above W is a positive (+) amount and G is a positive (+) amount, the lateral force S and the engine braking force E
And for the engine driving force K, the above (a) and (b)
and (c), and a toe-in effect is obtained, but in response to braking force B, the mounting surface Q rotates clockwise around the L axis, causing the wheel to change toe-out. , no toe-in effect can be obtained.

Furthermore, if W is a negative (-) amount and G is a negative (-) amount, unlike the previous example,
The axis of the first elastic bushing R ₁ in the first quadrant is on the rear inside of the vehicle body, and the axis of the second elastic bushing R ₂ in the second quadrant is
are arranged so that their axes are inclined toward the rear and outside of the vehicle body. In response to lateral force S, rotational displacement occurs and toe-in changes in the same way as in case (a) above. In response to braking force B, the mounting surface Q rotates around the M or L axis, and in response to engine braking force E, it rotates approximately around the L axis due to a negative offset, and also in response to engine driving force K. On the other hand, the rotational displacement is approximately around the M axis, and a toe-in effect is obtained in each case. At this time, in order to suppress the rearward displacement of the first elastic body bushing _R1 that prevents a toe-in change when the rotational displacement is caused by the engine braking force E, the first elastic body bushing _R1 is
Preferably, a stopper is provided at the rear end of _R1 .

5 and 6 show a modification of the arrangement structure of the ball joint P and the first and second elastic bushes R ₁ and R ₂ . In FIG. 5, the ball joint P is located at the coordinates (X, located in the second quadrant of Y),
This is an example in which the first and second elastic bushes R ₁ and R ₂ are located in the third and fourth quadrants.

In this example, as shown in Fig. 5, the offset amount W of the mounting surface Q of △PR ₁ R ₂ on the wheel center O is
is the positive (+) amount, and the offset amount G on the ground plane
When is a negative (-) amount, (a)' In response to the lateral force S, the mounting surface Q rotates clockwise around the N axis. At that time, the amount of elastic displacement of the first elastic bushing _R1 in the third quadrant is the fourth
If it is set to be larger than the second elastic bush _R2 in the quadrant, the toe-in will change.

(b)' In response to the brake force B, the mounting surface Q rotates around the L axis or the M axis, causing a toe-in change.

(c)′For the engine braking force E, the mounting surface Q is M
By rotationally displacing the shaft in a counterclockwise direction, the first elastic bushing R1 in the third quadrant is elastically deformed toward the rear inside of the vehicle body as shown in the figure, and the second elastic bushing _R1 in the fourth quadrant is
Toe-in change can be obtained by tilting the axes of each of the bushes R ₁ and R ₂ so as to elastically deform the elastic bush R ₂ toward the rear and outside of the vehicle body.

(d)′For the engine driving force K, the mounting surface Q is L
It rotates counterclockwise around the axis and changes toe-in. In this case, it is preferable to provide a stopper at the front end of the second elastic bushing _R2 in the fourth quadrant in order to prevent the second elastic bushing _R2 from moving inward of the vehicle body, which would impede the toe-in effect.

In addition, when the above W and G are both (+) amounts, the above (a)', (b)', and (c)' are applied to the lateral force S, engine braking force E, and engine driving force K. The toe-in changes as in the case. In response to braking force B, the mounting surface Q is rotationally displaced around the M axis in a counterclockwise direction, and due to the inward displacement of the first elastic body bushing _R1 and the outward displacement of the second elastic body bushing _R2 within the vehicle body. Toe-in change is possible.

Furthermore, when W and G are both (-) amounts, toe-in changes with respect to lateral force S as in case (a) above. In response to braking force B and engine braking force E, the mounting surface Q rotates counterclockwise around the L axis and changes in toe-in. In this case, it is preferable to provide a stopper at the front end of the second elastic bushing _R2 . Also, the engine driving force K
, the mounting surface Q is rotated clockwise around the M-axis, and the mounting surface Q is rotated clockwise around the M axis, and the mounting surface Q is rotated so that the first elastic bushing _R1 can be displaced inward from the vehicle body, and the second elastic bushing _R2 can be displaced outward from the vehicle body. By tilting the axes of bushes R ₁ and R ₂ , toe-in can be changed.

In addition, in FIG. 6, the ball joint P is located in the first quadrant of the coordinates (X, Y), and the first and second elastic bushings R ₁ and R ₂ are located in the third and fourth quadrants.
This is an example of a quadrant.

In this example, as shown in Fig. 6, the offset amount W of the mounting surface Q of △PR ₁ R ₂ on the wheel center O is
When is a positive (+) amount and the offset amount G on the ground plane is a negative (-) amount, (a)''For lateral force S, the above mounting surface Q is
As mentioned in (a)', a toe-in effect is obtained by rotating clockwise around the N-axis, and in this case, the ball joint P, which is the center of rotation of the mounting surface Q, is aligned with the line of action of the lateral force S. On the other hand, since it is offset rearward, a moment is generated around the L axis, and this moment ensures the toe-in change.

(b)'' In response to the brake force B, the mounting surface Q rotates around the M-axis or the L-axis, and the toe-in changes as in the case of (b)' above.

(c)″For the engine braking force E, the mounting surface Q is M
It is possible to obtain a toe-in effect in the same way as in the case (c)' by rotating and displacing the shaft in a counterclockwise direction.

(d)''For the engine driving force K, the mounting surface Q is L
It is preferable that the toe-in is changed by rotationally displacing counterclockwise around the axis, as in the case (d)' above, and that a stopper is provided at the front end of the second elastic bush _R2 in the fourth quadrant.

In addition, when W and G are both (+) amounts, the mounting surface Q is (a)'', (c)'', ( d)″
It shows the same operating characteristics as in the case of , and a toe-in effect can be obtained. In addition, in response to the braking force B, the mounting surface Q is rotationally displaced around the M axis in a counterclockwise direction, displacing the first elastic bushing _R1 in the third quadrant inwardly into the vehicle body, and A toe-in effect can be obtained by tilting each axis so as to displace the second elastic bushing _R2 outward from the vehicle body.

Furthermore, when W and G are both (-) amounts, toe-in changes with respect to lateral force S as in case (a)'' above. Also, with respect to engine braking force E and engine driving force K, the toe-in changes. On the other hand, similarly to the case where the ball joint P is located in the second quadrant, the mounting surface Q is rotated around the L axis for B, the L axis for E, and the M axis for K, resulting in a toe-in effect. is obtained.

Therefore, in this way, the mounting surface Q rotates around the ball joint P in response to the lateral force S, and the toe-in of the wheels 4 (15, 23) can be changed, thereby preventing oversteering. This can improve the running stability of the vehicle.

Moreover, the mounting surface Q rotates around the ball joint P to obtain a toe-in effect even when the other brakes B, engine braking force E, and engine driving force K act on the wheels 4 (15, 23). Therefore, running stability can be further improved.

In addition, a toe-in effect can be obtained for the above-mentioned various wheel actions by the simple structure of the float connection, which is a combination of the ball joint P and the first and second elastic bushings 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 the acting force of the rear suspension.

Furthermore, since the rotational displacement of the mounting surface Q is performed around the ball joint P, there is little deviation of the wheel in response to the applied force, and the behavior to change toe-in is performed stably. It can be made more reliable.

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, an example was shown in which it is applied to a semi-trailing type, a strut type, and a deion type rear suspension, but the present invention is also applicable to various double link type rear suspensions such as the Witsubon type or various swing arm type rear suspensions. 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 and the wheel hub are connected to the ball joint P and the first and second arms. It is floated by the second elastic bushes R ₁ and R ₂ .

Furthermore, the arrangement structure of the ball joint P and the first and second elastic bushes R ₁ and R ₂ can be in various configurations in addition to the examples shown in FIGS. 4 to 6 above. The point is to position the ball joint P in one of the first, second, and fourth quadrants in the coordinates (X, Z), and to connect the first and second elastic bushings.
R ₁ and R ₂ may be located in two of the remaining three quadrants excluding the quadrant in which the ball joint P is located.

Of these, especially when the ball joint P is located in the fourth quadrant as shown in Fig. 4, the lateral force S
and that an acting force of approximately 1:1 is applied to the elastic bushes R ₁ and R ₂ in the first and second quadrants relative to the brake force B (the ball joint P is in the first and second quadrants). (When the force is applied in the ratio of 1:2), the elastic bush
This is preferable in that it increases the durability of R ₁ and R ₂ , facilitates strength design, increases the stability of its behavior characteristics, and reliably changes toe-in with respect to lateral force S.

Moreover, although the right wheel at the rear of the vehicle body has been described in FIGS. 4 to 6, 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 P and the first and The ball joint is float-coupled with the second two elastic bushings, and the first horizontal-vertical coordinate of the ball joint is based on the wheel center when viewed from the left side of the vehicle body.
Place it in either the second or fourth quadrant, and place it in the first quadrant above.
and the second elastic bush in two of the remaining three quadrants.
With a simple configuration in which the wheels are placed in each quadrant, it is possible to change the wheel toe-in in response to lateral force, and it is also possible to obtain toe-in effects in response to braking force, engine braking force, and engine driving force. With one simple structure, the toe-in can be changed in response to any wheel acting force, and this greatly contributes to improving the running stability of the vehicle and simplifying the rear suspension structure.

Furthermore, since it rotates around the ball joint in response to the wheel acting force,
This has the advantage that there is little displacement of the wheel due to acting force, excellent behavioral stability, and that the above-mentioned toe-in effect can be made more reliable.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the invention, FIG.
FIG. 2 is a perspective view showing the second embodiment; FIG. 3 is a perspective view showing the third embodiment; FIG.
6 through 6 are schematic explanatory diagrams each showing an example of the arrangement structure of the ball joint and the first and second elastic bushings. 1...Semi-trailing arm, 2...Subframe, 3...Wheel hub, 4...Wheel, 10...Strut hub, 12...Suspension arm, 1
3, 14...Subframe, 15...Wheel, 16
...Wheel hub, 20...Rear axle tube, 22...Tension rod, 23...Wheel, 24...Wheel hub, P...Ball joint, _R1 ...First elastic bushing, _R2 ...Second elastic bushing, O...Wheel Center.

Claims (1)

[Claims] 1. A rear suspension component whose one end is rotatably supported on the vehicle body, a wheel hub which rotatably supports a wheel, and a rocking motion between the wheel hub and the rear suspension component about one point. A ball joint that freely connects, a first elastic body bush that connects the wheel hub and the rear suspension component, and a second elastic body that connects the wheel hub and the rear suspension component. The ball joint is located in one of the first, second, and fourth quadrants in horizontal and vertical coordinates based on the wheel center when viewed from the left side of the vehicle body, and the ball joint The rear suspension is characterized in that the body parts are located in two of the remaining three quadrants excluding the quadrant where the ball joint is located.