JPS6143203B2 - - 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.
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
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 engine 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 body bushing and the second elastic body bushing are located in two of the remaining three quadrants, respectively.
In response to lateral force, the mounting surface including the three connection points mentioned above is rotated around the ball joint to change the toe-in of the wheel, and also in response to other braking force, engine braking force, and engine driving force. The toe-in can 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 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 sub-frame 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. Others, 1st
In the figure, 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. 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. 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 viewed 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, and the first and second elastic bushings R ₁ and R ₂ are located in the first and second quadrants of the remaining three quadrants, respectively.

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.
When G is a negative (-) amount, (a) Since the lateral force S acts in the +Y direction with respect to the wheel grounding point, 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 is approximately aligned with the L axis with the ball joint P as the center due to the (-) amount of G. The wheel is rotated counterclockwise and the toe-in of the wheel changes. At this time, the mounting surface Q further attempts to rotate counterclockwise around the M axis around the ball joint P, so the first elastic bushing R ₁ in the first quadrant moves toward the inside of the vehicle body, and the second The second elastic bushing _R2 in the quadrant is displaced outward from the vehicle body, resulting in toe-out. Therefore, in order to prevent the counterclockwise rotation of the mounting surface Q around the M-axis, and to suppress the displacement of the first elastic bushing _R1 in the first quadrant inward of the vehicle body that would impede the above-mentioned toe-in effect, Preferably, a stopper is provided at the front end of the bush _R1 .

(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 (c)
It shows the same behavior characteristics as case (d), 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. In this case, it is preferable to provide a stopper at the rear end of the first elastic bushing R1 in order to prevent the rearward displacement of the first elastic bushing _R1 which prevents a toe-in change during rotational displacement in response to the engine braking force _E.

Further, FIGS. 5 and 6 show a modification of the arrangement structure of the first and second elastic bushings R ₁ and R ₂ . In Fig. 5, the ball joint P is located in the fourth quadrant at the coordinates (X, Y), and the ball joint P is located in the fourth quadrant.
This is an example in which the elastic bush R ₁ remains located in the first quadrant, and the second elastic bush R ₂ is located in the third quadrant.

In this example, as shown in Fig. 5, the offset amount W of the mounting surface Q of ΔPR 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 lateral force S, the mounting surface Q rotates around the L-axis or N-axis around the ball joint P, and the center of rotation ( P) is offset rearward with respect to the line of action of the lateral force S, resulting in a toe-in change.

(b)′For brake force B, the mounting surface Q is as shown in (b) above.
As in the case of , the toe-in is changed by rotating counterclockwise around the L axis with P as the center. Further, it is preferable to provide a stopper at the front end of the first elastic bushing _R1 in the first quadrant.

(c)′ In response to the engine braking force E, the mounting surface Q rotates around the M axis as in the case of (c) above, and the axes of the first and second elastic bushes R ₁ and R ₂ A toe-in effect can be obtained by tilting it so that it is displaced in the toe-in direction. That is, in the case of this embodiment, the axis of the first elastic bushing _R1 is directed toward the rear and outside of the vehicle body.

(d)' In response to the engine driving force K, the mounting surface Q undergoes a rotational displacement around the L axis and changes in toe-in, as in the case of (d) above. Further, it is preferable to provide a stopper at the front end of the first elastic bushing _R1 in the first quadrant.

Further, when the above W and G are both (+) amounts, toe-in changes with respect to the lateral force S as in the above case (a)'. For engine braking force E, P
The toe-in changes by rotating around the M-axis or L-axis. In addition, in response to the engine driving force K, the toe-in changes by rotationally displacing around the L-axis or M-axis with P as the center (in this case, when the rotational displacement about the L-axis occurs, the first elastic bushing in the first quadrant It is preferable to provide a stopper at the front end of R ₁ ). In response to the brake force B, the mounting surface Q rotates clockwise around the L axis and changes toe-out, so no toe-in effect can be obtained.

Further, when both W and G are (-) amounts, the axis of the first elastic bushing _R1 is arranged so as to be inclined toward the rear inner side of the vehicle body. In response to the lateral force S, the toe-in changes as in the case (a)' above.
For braking force B, the mounting surface Q is either M axis or L axis.
Toe-in changes by rotational displacement around the axis. Also,
In response to the braking force E of the engine, the mounting surface Q rotates counterclockwise around the L axis to change toe-in. At that time, the first elastic bushing R ₁ in the first quadrant
It is preferable to provide a stopper at the rear end of the holder. In addition, in response to the engine driving force K, the mounting surface Q rotates counterclockwise around the M axis, and the first and second
A toe-in effect can be obtained by inclining the axes of each of the elastic bushes R ₁ and R ₂ so as to change in the toe-in direction.

Further, FIG. 6 shows an example in which the first elastic bush R ₁ is located in the second quadrant and the second elastic bush R ₂ is located in the third quadrant at the coordinates (X, Z).

In this example, as shown in Fig. 6, the offset amount W of the mounting surface Q of ΔPR 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 will cause the ball joint P to The toe-in is changed by rotating and displacing counterclockwise around the L axis as the center.

(b)''For braking force B, the mounting surface Q is as shown in (b) above.
As in the case of , the toe-in is changed by rotationally displacing it counterclockwise around the L axis. In this case, it is preferable to provide a stopper at the front end of the first elastic bushing _R1 in the second quadrant to prevent its forward displacement.

(c) In response to the engine braking force E, the mounting surface Q rotates around the M axis as in the case of (c) above, and the axes of the first and second elastic bushes R ₁ and R ₂ By tilting in the toe-in direction, a toe-in effect can be obtained.

(d) In response to the engine driving force K, the toe-in changes by rotating around the L axis as in the case of (d) above. In this case as well, the first elastic bushing R ₁ in the second quadrant Preferably, a stopper is provided at the front end of the holder.

In addition, when the above W and G are both (+) amounts, the above (a)'', (c)'', and (d)'' are respectively applied to the lateral force S, engine braking force E, and engine driving force K. It exhibits the same behavior characteristics as in the case of , and a toe-in effect is obtained.However, in response to the brake force B, the mounting surface Q rotates clockwise around the L axis and changes toe-out, so no toe-in effect is obtained.

Furthermore, when both W and G are (-) amounts, the axis of the first elastic bushing _R1 is arranged so as to be inclined toward the rear of the vehicle body. In response to lateral force S, the toe-in changes as in case (a)'' above.In response to brake force B, the mounting surface Q rotates around the M-axis or L-axis and changes in toe-in. A toe-in effect is obtained by rotating around the L axis in response to the braking force E and around the M axis in response to the engine driving force K. Therefore, in this way, the mounting surface Q is rotationally displaced around ball joint P, and wheel 4
(15, 23) can be changed toe-in, so oversteering can be prevented and the running stability of the vehicle can be improved.

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.

Furthermore, since the rotational displacement of the mounting surface Q is performed around the ball joint P located in the fourth quadrant, it is offset rearward with respect to the line of action of the lateral force S. In contrast, the mounting surface Q is reliably rotationally displaced in the toe-in direction, and the toe-in change of the wheel is reliably performed.
Also, with respect to the lateral force S and the brake B, the elastic bushes R ₁ and R ₂ located in the first or second quadrant
Because the center of rotation P is in the fourth quadrant, the lever ratio is only about 1:1 acting force, and the acting force is half of that when the center of rotation P is in the first or second quadrant. Since the bushes R 1 and R ₂ are relatively small, the design strength of the bushes R ₁ and R 2 is not difficult and easy, and their durability can be increased. Furthermore, since the rotation center P is in the fourth quadrant and the distance in the vertical direction from the point of application of the lateral force S and the brake force B (wheel grounding point) is relatively short,
Since there is little movement deviation of the wheel in response to the lateral force S and the brake force B, 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, 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 Utsushu Bon type, a connecting hub that connects two upper and lower arms extending in the left-right direction of the vehicle body constitutes the rear suspension component in the present invention, and the connecting hub and the wheel hub are connected by a ball joint P and a first and second arm. It is sufficient to connect it with 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 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 ball joint is located in the fourth quadrant of 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 the first and second elastic bushings. With a simple configuration in which the wheels are located in two of the remaining three quadrants, it is possible to reliably change the toe-in of the wheel in response to lateral force. It is also possible to obtain toe-in effects for wheel actions of other braking forces, engine braking forces, and engine driving forces, and one simple float connection structure can provide toe-in effects for all wheel actions. This greatly contributes to improving the running stability of the vehicle and simplifying the rear suspension structure.

Furthermore, since the rotation changes around the ball joint located in the fourth quadrant of the coordinates based on the wheel center in response to wheel acting forces such as lateral forces, the acting force on the elastic bushings in response to lateral forces is small and its durability This has the advantage that not only can the wheel be improved in terms of performance, but also that there is little displacement of the wheel due to applied force, resulting in excellent behavior stability in the toe-in direction, and that the 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 showing examples of the arrangement structure of the ball joint and the first and second elastic bushings, respectively. 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 the fourth quadrant in the horizontal-vertical coordinates based on the wheel center when viewed from the left side of the vehicle body, and the first elastic body bush and the second elastic body bush are located in the remaining three quadrants. The rear suspension is characterized by being located in each of the two quadrants.