JPS58191614A - Rear suspension - Google Patents

Abstract

PURPOSE:To achieve a greater operational stability during the cornering by arranging a ball joint in the second quadrant of the horizontal-vertical coordinate with the rear wheel center as reference as viewed from the left side of a body and rubber bushes in the first and fourth quadrants. CONSTITUTION:When a lateral force S works on the ground contact G, a tire is caused to rotate in the toe-in direction about the line running between a ball joint 1 and a rubber bush 3 in the fourth quadrant. A braking force B causes the tire to the displaced in the toe-in direction about the axis L due to the offset G - at the ground contact G. At the same time, a toe-in displacement takes place likewise due to an effect of guiding the counterclockwise rotation about the axis M in the toe-in direction depending on the tilting of bushes 3 and 4 overcoming the tendency to toe out which results from an offset W+ at the wheel center W by the braking force E. With respect to a driving force K, the tire is caused to be displaced in the toe-in direction about the axis L resulting from an offset W+ at the center. Here, it is desirable to provide a stopper on either the bush 3 or 4 to regulate the clockwise rotation about the axis M.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rear suspension for an automobile, and more particularly to a novel rear suspension with excellent toe-in effect.

In automobile glue V suspension, handling stability,
In order to improve riding comfort, it is desired that the tires be toe-in during driving, especially when cornering. In other words, as is well known, during cornering, the centrifugal force applied to the car body is horizontal to the suspension.
In order to increase the turning limit G, it is desirable for the tire to counteract this lateral force with a large resistance force. This drag can be increased by toe-in the tire and increase the slip angle.
If you increase this drag and improve the grip of the rear wheel,
It can strengthen the understeer tendency and improve the stability of the car. Furthermore, when you press and release the accelerator during cornering, driving force and braking force are applied to the tires, but when you release the accelerator, the tires tend to suddenly toe out, and when you press the accelerator, they tend to toe in. . Then, during cornering, the tire changed to 1.-
As a result, the steering stability (hereinafter referred to as steering stability) deteriorates. In addition, if you step on the brakes or apply engine braking, the rubber bushings installed to improve ride comfort (braking will occur because the rubber bushings are located inside the tire's ground contact point).
This will cause the vehicle to toe out, resulting in poor steering stability. The softer the rubber bushings, the better the ride comfort, so a car that is comfortable to ride will have poor handling. Therefore, a rear suspension that provides toe-in even when braking force is applied by brakes or engine braking is desired. In other words, a rear suspension that always tends to move 1-1 in will always realize stable cornering. Furthermore, the toe-in tendency of the rear suspension is desirable not only when cornering, but also from the standpoint of high-speed straight-line performance, which is particularly required for sports cars. That is, the road surface is actually not completely flat and always has irregularities of various sizes, but these irregularities cause disturbances to the tires from various directions. In addition, while driving, the vehicle is affected by crosswinds as well as lateral forces, but even if it is not a crosswind, it acts as a disturbance to the vehicle from all directions and acts on the tires.

Even in response to these disturbances, if the rear suspension always acts to move the rear wheels 1-in, the car will tend to understeer and become stable. Regardless of the cause, these disturbances end up acting on the tires as the aforementioned lateral force, braking force, or driving force.

Therefore, the rear suspension is desired to have the effect of toe-in the tires against all of the lateral force, braking force (there are two types: brake and engine brake), and driving force. To explain these external forces in detail, the lateral force represented by the thrust load during cornering is the force that acts from the outside to the inside of the tire's grounding point, and the braking force when applying the brakes is the force that acts in front of the tire's grounding point. The force from the engine brake is the force that acts on the wheel center of the tire from front to back, and the driving force is the force that acts on the wheel center from the back to the front.

This can be expressed in a table as shown below.

3- Conventionally, rear suspensions have been equipped with a toe-in effect against lateral force during cornering, but all of them are structurally somewhat complex. For example, the one described in Japanese Patent Publication No. 52-37649 uses three rubber bushings and the hardness of the bushings is changed. The one described in No. 954 has a wheel hub supported via a vertical shaft and a spring, and has a complicated structure. In addition, this kind of rear suspension that is known in the past has the above 4g! It does not realize the toe-in effect for all outside saws, and is mainly effective only against lateral force.

An object of the present invention is to provide a novel rear suspension that effectively turns the rear wheels 1-4-in against external forces, particularly during cornering, with an extremely simple structure.

Furthermore, the present invention has an extremely simple structure that enables toe-in of the rear wheels in response to any external force such as lateral force, braking force, engine braking force, or driving force, regardless of whether the vehicle is turning or going straight. The objective is to provide a completely new type of suspension system that makes it possible to create highly safe cars.

The rear suspension of the present invention connects a vehicle body side support member, which is partially connected to the vehicle body, and a rear wheel hub using one ball joint and two rubber bushes. The second horizontal-vertical coordinate when the wheel center as seen from the left side of the vehicle body is taken as a reference.
One of the rubber bushes is located in the fourth quadrant, and the usage is located in the first quadrant.

In the present invention, the vehicle body side support member refers to, for example, a semi-trailing arm of a semi-trailing type rear suspension, a strut of a strut type rear suspension, an upper and a lower arm of a wishbone type rear suspension, and a dove ion of a dove ion type rear suspension. It is a general term for various types of support members such as tubes attached to the vehicle body side, and the type of rear suspension that is the subject of the present invention is not limited to any specific type as long as it supports tires in a toe-in manner.

Furthermore, the quadrant defined in the present invention is a quadrant in rectangular coordinates when looking at the rear wheel from the left side of the vehicle body and imagining horizontal and vertical orthogonal axes with the wheel center as the center.
It is assumed that each of the fourth quadrants includes the axes at both ends that limit the quadrant (for example, in the first quadrant, the right half of the horizontal axis and the upper half of the vertical axis).

According to the rear suspension of the present invention, it is possible to effectively toe-in the tire when a lateral force is applied, and it is also possible to toe-in the tire when any of the four types of external forces are applied.

This toe-in effect is obtained by arranging the ball joint and rubber bush of the suspension as described above, and utilizes the deformation of the rubber bush around the vertical and horizontal axes passing through the ball joint. By rotating the wheel hub, toe-in is achieved in response to various external forces.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

1 to 6 show an embodiment in which the present invention is applied to a semi-trailing type rear suspension.
Figure 1 is a plan view of the right rear wheel, Figure 2 is a side view of the right rear wheel, and Figure 3 is an elevation view of the rear right wheel. It is shown cut out or omitted. Figure 4A is a cross-sectional view taken along the line A--A in Figure 2, Figure 4B is a cross-sectional view taken along the line A--A in Figure 4A, Figure 5A is a cross-sectional view taken along the line B-B in Figure 2, and Figure 5B is a cross-sectional view taken along the line A--A in Figure 2. is a sectional view taken along line 8--B in Fig. 5A, and Fig. 6 is a sectional view taken along line C in Fig. 2.
-C line sectional view. FIG. 2 is a side view of the vehicle body as seen from the right side, and the 1.2 and 3.4 quadrants in the horizontal-vertical coordinates based on the wheel center as seen from the left side are denoted by 1.
Indicated by II, II, IV.

As shown in FIG. 1, the semi-trailing arm 10 has a branched shape into two arms, an inner arm 10a and an outer arm 10b. It is swingably supported around a shaft 117-. The rear end 100 of this semi-trailing arm 10 is separated from a wheel hub 22 that rotatably supports a wheel 21 of a tire 20, and both are connected to a ball joint by two rubber bushes 3.4 and one ball joint 1. 1 and is displaceably coupled with some elasticity. That is, in the illustrated embodiment, three arms 22a, 22b, and 22c are provided on the wheel hub 22 side (see FIGS. 2 and 3), and the tips of these arms are connected to the rear end of the semi-trailing arm 10. Three shaft supports 12- with 1100k
a, 12b, and 12C.

That is, the first arm 22a is elastically supported by the rubber bush shaft support 12a located in the first quadrant l and whose upper (or rear) side faces outward, and the second arm 22b
is elastically supported by a rubber bush shaft support 121) located in the fourth quadrant Iv and whose rear (or upper) side faces outward, and the third arm 22c is supported by a ball joint support part 120 located in the second quadrant II. It is rotatably supported around one point.

As shown in Figures 4A, 4B, 5A, and 5B, the rubber bushings 12a, 12b that pivotally support the 8-1 and 2nd arms 22a, 22b are axially supported in the axial direction and in the direction perpendicular to the axis. Rubber bush 13a that allows displacement.

13b, the rubber bushing 13 of the rubber bushing shaft support 12a located in the first quadrant I
A highly rigid material 138' is inserted inside so that a is deformed only outwardly, and a stopper 13b' is installed on the rubber bushing shaft support 12b located in the fourth quadrant (2) to limit forward displacement. It is inserted into the front side of the rubber bush 13b. The ball joint support part 12c that supports the third arm 22'0 at a point is provided with a spherical part 13c that does not allow displacement in the axial direction but only allows rotation around one point. It rotates around 13C and is supported like a vine.

In this way, the wheel hub 22 has three arms 22a, 22b,
22c, two rubber bushings 12a, 12
b (corresponding to the rubber bush 3.4) and one spherical portion 13C (corresponding to the ball joint 1), which are elastically and displaceably connected around the ball joint 1. With support from these three points, this rear suspension has the effect of toeing the tires against all of the lateral force (S), braking force (B), engine braking force (E), and driving force (K). .

Hereinafter, the principle of operation of various embodiments of the present invention including the structures of the above embodiments will be explained in detail with reference to FIGS. 7.8.9.

In FIG. 7, a perspective view of the rear right tire of the automobile viewed from the rear left is shown in the center, and projected views of this from the rear, left side, and above are shown on the left, right, and below. In the rectangular coordinates formed by the horizontal axis H and the vertical axis V, which extend in the longitudinal direction of the vehicle body, centering on the wheel center W, the ball joint 1 is arranged in the second quadrant
Rubber bushes 3 and 4 are arranged in quadrant IV and first quadrant I.

In such a basic arrangement, the plane formed by the ball joint 1 and the rubber bush 3.4 (represented by reference numeral 10 in the projection view from the rear) is either on the outside (-) or on the inside with respect to the wheel center W. (+), and whether it is outside (-) or inside (+) with respect to the grounding point G (hereinafter referred to as off-sera i-), the type of arrangement is W1G+, W+G-, VIG+, W-G-4
Classified as a species. Among these, W10G- is particularly effective, and FIG. 7 shows an example of this W10G- (that is, the offset at the wheel center is (10) and the offset at the grounding point is (-)).

Hereinafter, the toe-in effect with respect to external force in the case of W10G- will be shown in detail with reference to the drawings.

The vertical virtual axis passing through the ball joint 1 is defined as 1, the horizontal virtual axis as M, and the longitudinal virtual axis as N. 7th
In the example shown in the figure, the direction in which the lower rubber bushing 3 is easily deformed (direction of the center axis of the cylindrical rubber bushing) is tilted outward at the rear (or upward), and the upper rubber bushing 4
The direction of easy deformation is tilted outward toward the rear (or upward).

Lateral force (S) acts on the tire grounding point G from outside to inside, braking force (B) acts on the tire grounding point G from front to rear, and engine braking force (E) acts on the tire grounding point G from the front to the rear. The driving force (K) acts on the wheel center W from the back to the front.

11- When a lateral force (S) acts on the grounding point G, the wheel hub or tire is rotated in the toe-in direction around the line connecting the ball joint 1 and the rubber bush 3 in the fourth quadrant, and the brake force (B) is is the offset at the grounding point G (G
-) causes displacement in the toe-in direction around the L axis, and at the same time causes counterclockwise rotation around the M axis, and this rotation is guided in the toe-in direction by the inclination of the two rubber bushes 3 and 4. This effectively causes toe-in displacement. That is, the rubber bushing 4 in the first quadrant I has a center axis that is approximately perpendicular to the line connecting the ball joint 1 and the rubber bushing 4 around the M-axis so as to guide displacement around the M-axis outward. When the wheel hub rotates, the rear of the wheel hub is tilted outward so that the rear of the wheel hub is displaced outward. Further, the rubber bush 3 in the rear fourth quadrant 3 is tilted so that the rear (or upper part) is directed outward so that the rear is displaced outward when the wheel hub rotates around the M axis.

For the engine braking force (E), the 12-in direction with respect to counterclockwise rotation around the M axis due to the inclination of the two rubber bushes 3 and 4 is greater than the 12-in direction due to the offset W+ at the wheel center W. Increase the effect of guidance to obtain toe-in displacement. In this case, in order to restrict the toe-out movement around the L axis due to offset t-<W+), a stopper (
It is preferable to provide 13a) in FIGS. 4A and 4B. Further, with respect to the driving force (K), an offset (W+) at the wheel center W allows displacement in the toe-in direction around the L axis. In this case, it is preferable to provide a stopper (FIG. 5A, 13b') in front of at least one of the rubber bushings 3.4 in order to restrict clockwise rotation around the M-axis and to ensure a toe-in effect.

As mentioned above, the two rubber bushes 3 and 4 are attached to the fourth. Even when provided in the first quadrant, toe-in displacement can be produced in response to four types of external forces.

The above explanation is for the case where the offset is W+G-, but the same effect can be obtained with W, +G+ or W-G-.

Next, the case of an offset of W10G+ will be explained in detail with reference to FIG. In this case, rubber bushings 3 and 4
The orientation may be the same as in the case of FIG.

When a lateral force (S) acts from the outside to the inside at the grounding point G, it tries to rotate the tire clockwise around the N axis as seen from the rear, but as in the previous case, the pole shimindo 1
By rotating the tire in the direction of 1-1 in around the line connecting the rubber bush 3 and the rubber bush 3, a toe-in effect can be obtained.

With respect to the brake force (B), a toe-out force is also generated due to the offset of W + G + 0, but if the magnitude of this offset is small, this effect is small, and it is more likely that the rotation around the M axis is controlled by the rubber bush at an inclination of 3°4. By guiding in the toe-in direction, it becomes possible to cause toe-in displacement as a result.

Similarly, the rotation of the engine braking force (E) around the M axis is guided by the rubber bushes 3 and 4, so that the tire can be toe-in.

For the driving force (K), this is the engine braking force (
Since the external force is exactly opposite to E), by providing a stopper in front of the rubber bushing 3, the tire is rotated in the toe-in direction around the line connecting the rubber bushing provided with the stopper and the ball joint 1, and the tire is rotated in the toe-in direction. effect can be obtained.

In this way, even if the offset is W10G0, ball joint 1 located in the second quadrant and ball joint 1 located in the fourth quadrant,
Due to the action of the rubber bushing 3°4 located in the first quadrant, the tire is always displaced in the toe-in direction in response to the above four types of external forces including the lateral force (S).

Next, the case where the offset is %%"-G- will be explained with reference to FIG. is tilted in the opposite direction to that in Figures 7 and 8.
is being pulled. That is, the central axis of the lower bushing 3 extends from the front or lower outer side toward the rear or upper inner side, and the central axis of the upper bushing 4 extends from the lower side or rear inner side toward the upper or front outer side.

In this embodiment, the lateral force (S) rotates the tire around the L axis in the toe-in direction around the line connecting the ball joint 1 and the lower rubber pusher 15-3, which causes the brake force (B) and the engine brake. Force (E) is O'7
Rotate in the toe-in direction around the L axis by setting W-G-. However, in the case of these braking forces (B, E), if a stopper is not provided after the rubber bush 3 to restrict the rotation in the counterclockwise direction around the M axis, the rubber bush 3,
Due to the guidance according to the direction 4, it is displaced in the toe-out direction.

With respect to the driving force (K), clockwise rotation around the M axis is guided in the toe-in direction by the orientation of the two rubber bushes 3 and 4, and a toe-in displacement can occur.

The direction of this rubber bushing 3.4 is offset W-G.
This is to cause a displacement toward toe-in even with respect to the driving force (K') which acts only in the toe-out direction with respect to -.

In this way, even if the offset is W-G-, it is possible to provide a toe-in effect for all of the above four types of external forces.

The toe-in effects for the four types of external forces in the various embodiments described above can be summarized as shown in the table below. The symbols in the table have the meanings in the explanation above.

In the table, "axis" refers to the relevant rotation axis, and "stopper" refers to the required position of the stopper.

As is clear from the above-mentioned embodiments, when an offset is used, the rotation around the L axis is involved, and when the inclination of the rubber bushing is used, the rotation around the M axis (formed by the ball joint and the two rubber bushes) is related. The rotation of the surface) is related. The magnitude of the displacement caused by displacing and guiding these rotations or rotations can be adjusted by selecting the offset size, the inclination of the rubber bushing, or the hardness of the rubber bushing so that the tire is displaced in the toe-in direction as a result. Thus, the desired toe-in effect can be obtained.

According to the present invention, as is clear from the above explanation, one pole shim ind is arranged in the second quadrant (IV), one rubber bush (elastic body bush) is arranged in the fourth quadrant IV, Another rubber bush placed in one quadrant provides a rear suspension that always keeps the tires 1-in against the four types of external forces: lateral force, braking force, engine braking force, and driving force, making cornering easier. It is possible to realize a car that constantly stabilizes the car while driving, and has improved handling stability without impairing ride comfort. Furthermore, this toe-in effect is advantageous in realizing a sports car with excellent straight-line performance at high speed, so the rear suspension according to the present invention has extremely high practical value.

[Brief explanation of the drawing]

Figures 1 to 6 show an embodiment in which the present invention is applied to a semi-trailing type rear suspension.
Figure 1 is a plan view of the right rear wheel, Figure 2 is a side view of the right rear wheel, and Figure 3 is an elevation view of the rear right wheel. What is shown in section or omitted, Fig. 4A is A- in Fig. 2.
4B is a sectional view taken along line A--A' of FIG. 4A, FIG. 5A is a sectional view taken along line B-B of FIG. 2, and FIG.
FIG. 6 is a sectional view taken along line B-B in FIG. 2, FIG. As an example, FIG. 8 is a principle diagram showing an example of the present invention in which the offset is W10G1, and FIG. 9 is a principle diagram showing an example of the present invention in which the offset is WG-. 1... Ball joint 3.4... Rubber bush G... Grounding point W... Wheel center S... Lateral force B...
・Brake force E...Engine brake force K...
...Driving force L... Vertical axis passing through the ball joint M... Horizontal axis passing through the ball joint (axis parallel to the axle) N... Front and rear passing through the ball joint Axis...
...Quadrant 1 ■...Quadrant 2■...
・・・・3rd quadrant ■・・・・4th quadrant 3rd
Figure 4A Figure 4B Figure 6 3c

Claims (1)

[Claims] A vehicle body side support member that is partially connected to the vehicle body, a wheel hub that rotatably supports the rear wheel, and a ball joint that connects the wheel hub and the vehicle body side support member so as to be able to swing around one point. and two elastic bushings that elastically connect directly between the wheel hub and the vehicle body side support member, and the ball joint is located at the second horizontal-vertical coordinate of the wheel center reference when viewed from the left side of the vehicle body. The rear suspension is arranged in a quadrant, one of the two elastic bushings is located in the fourth quadrant, and its usage is located in the first quadrant. ,