JPS6144696B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rear suspension installed in an automobile, and more particularly to a rear suspension that performs reverse camber control of the wheel attitude when bumping.

In general, in the rear suspension of a car, when turning, a force (lateral force) and a bump load toward the turning center act on the left and right wheels, especially the wheels on the outside of the turning center. It is known that controlling the wheel attitude to toe-in or reverse camber is preferable in order to prevent oversteering and improve running stability.

Therefore, conventionally, rear suspensions that change the wheel toe-in in response to the above lateral force have been used.
The rear suspension arm, whose one end is swingably supported on the vehicle body, and the wheel hub, which rotatably supports the wheel, are float-coupled in at least two places, front and rear, and this coupling structure is connected with a spring at the front. 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 bushings is reduced. A version that is softer than the side rubber bushings has been proposed (Special Publication No. 52-37649).

However, all of the above conventional methods simply displace the spring or rubber bushing in the toe-in direction in response to the lateral force, so they not only cannot effectively exert the toe-in effect against the lateral force, but also have the disadvantage of not being able to effectively exert the toe-in effect against the lateral force. However, the wheel posture could not be controlled in any way, and running stability could not be sufficiently improved.

Therefore, the present invention has been made in view of the above, and uses a ball joint and an elastic body to connect a rocking member as a rear suspension component such as the rear suspension arm and a wheel support member such as a wheel hub. In addition to floating connection with the bushing, the rear suspension utilizes a stabilizer that has the function of increasing roll rigidity during rolling, and by generating a rigid reaction force in the left and right direction on the stabilizer when bumping, the wheel posture is adjusted when bumping. The purpose of this is to improve running stability by enabling reverse camber control.

In order to achieve this object, the configuration of the present invention includes: a swing member whose one end is swingably supported on the vehicle body; a wheel support member that rotatably supports a wheel;
a ball joint that connects the wheel support member and the swinging member so as to be able to swing around one point; an elastic bush that connects the wheel support member and the swinging member; and a stabilizer which is rotatably supported by the vehicle body and whose bent ends are connected to the left and right wheel support members, respectively, and the connection portion between the stabilizer and the wheel support member is connected to the ball joint of the wheel support member. It is arranged at a lower position than the connection point and higher than the rotation axis of the swinging member, so that when bumping, the connection part between the stabilizer and the wheel support member moves around the rotation axis of the swinging member. When the stabilizer is forced to rotate and a reaction force is generated outward in the left and right direction, the wheel support member is rotationally displaced in the reverse camber direction around the ball joint, causing the wheel to change in reverse camber. be.

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, in which numeral 1 denotes a semi-trailing arm as a swinging member extending substantially in the longitudinal direction of the vehicle body; One end of the arm 1, that is, the forked front end, is connected to a subframe 3 as a vehicle body component disposed in the left-right direction of the vehicle body via elastic bushings 2, 2 having an axis inclined inward toward the rear of the vehicle body. It is supported so that it can freely swing in the vertical direction. Further, 4 is a wheel hub as a wheel support member that rotatably supports the wheel 5. The wheel 5 is connected to the other end of a drive shaft 7 whose one end is connected to a differential 6.

Between the wheel hub 4 and the rear end of the semi-trailing arm 1, there is a ball joint P that can swing around one point, and two first and second elastic bushings R that are made of rubber bushings or the like. ₁
and _R2 .

Furthermore, 8 is a stabilizer arranged in the left-right direction of the vehicle body on the rear side between the left and right wheel hubs 4, 4, and the stabilizer 8 includes a torsion bar portion 8a extending in the left-right direction of the vehicle body, and a stabilizer 8 extending from both ends of the torsion bar portion 8a. It consists of arm parts 8b, 8b as ends bent forward, and is rotatable by elastic bushings 10, 10 attached to the vehicle body via control links 9, 9 at the left and right ends of the torsion bar part 8a. The front ends of the arm portions 8b, 8b are connected to the left and right wheel hubs 4, 4, respectively.

In addition, the connection portion 11 between the stabilizer 8 and the wheel hub 4 is located at a lower position than the connection point of the ball joint P of the wheel hub 4, and the rotation axis (elastic It is located at a higher position than the body bushes 2, 2). Therefore, the rotation axis of the semi-trailing arm 1 is inclined inward toward the rear of the vehicle body, and the rotation axis of the stabilizer 8 is disposed non-parallel to each other in the left-right direction of the vehicle body, so that when bumping, the above-mentioned The connecting portion 11 between the stabilizer 8 and the wheel hub 4 is forcibly rotated around the rotation axis of the semi-trailing arm 1, causing a difference in the rotation locus of the two, which causes the arm portion 8b of the stabilizer 8 to rotate. It is configured to generate a reaction force outward in the left-right direction. In FIG. 1, reference numeral 12 denotes a shock absorber consisting of a shock absorber and a coil spring.

Therefore, in the first embodiment, when the wheel 5 bumps, the semi-trailing arm 1 rotates upward about its connecting portion with the vehicle body (the elastic bushings 2, 2) as the rotation axis, and At the same time, the wheel hub 4 connected to the rear end of the semi-trailing arm 1 rotates upward. As a result, the arm portion 8b of the stabilizer 8 connected to the wheel hub 4 rotates upward about the torsion bar portion 8a, causing twisting in the torsion bar portion 8a. The roll rigidity is increased and an anti-roll effect is exhibited.

At this time, the rotation axis of the semi-trailing arm 1 is inclined inward to the rear of the vehicle body, and the stabilizer 8
The rotation axes of the two are in the left-right direction of the vehicle body and are non-parallel to each other, resulting in a difference in the rotation locus of the two.
That is, as shown in FIG.
is a vertical upward rotation locus L ₁ in the vertical projection seen from the rear of the vehicle, whereas the connection portion 11 between the wheel hub 4 and the stabilizer 8, which is constrained and controlled by the rotation of the semi-trailing arm 1, is It is forced to rotate around the rotation axis of semi-trailing arm 1,
Since the connecting portion 11 is located at a higher position than the rotation axis of the semi-trailing arm 1, the rotation trajectory _L2 is inclined upward and inward. As a result, this rotation locus difference causes a reaction force directed outward in the left-right direction of the vehicle body as a rigid reaction force on the arm portion 8b of the stabilizer 8.

The outward reaction force in the left and right direction of the stabilizer 8 is caused by the fact that the connecting portion 11 is located at a lower position than the connection point of the ball joint P of the wheel hub 4. By acting as a moment force to rotate the wheel 5 in the reverse camber direction, the wheel 5 is caused to change the reverse camber.

Therefore, when bumping, the wheel hub 4 is caused by the outward reaction force in the left and right direction of the stabilizer 8.
Since the wheel 5 can be changed in reverse camber by rotationally displacing the wheel around the ball joint P, reverse camber control of the wheel posture can be performed reliably and effectively, and running stability can be significantly improved. can.

Moreover, the reverse camber control of the wheel posture described above uses the ball joint P and the elastic bushing.
Since this can be achieved by a simple structure of float coupling in combination with R ₁ and R ₂ and by using the existing stabilizer 8, the structure can be simplified and it can be implemented easily and at low cost.

Furthermore, since the above-mentioned reverse camber control of the wheel posture is performed by rotational displacement around the ball joint P, the displacement of the wheel 5 against the reaction force of the stabilizer 8 is small, and the behavior of the reverse camber change is stable. Therefore, the reverse camber effect can be made more reliable.

FIG. 2 shows a second embodiment in which the present invention is applied to a strut-type rear suspension. Reference numeral 20 denotes a strut hub as a swinging member that supports a strut 21. The distal ends of two-link rear suspension arms 22, 22 extending in the rear suspension arms 22, 22 are connected via elastic bushings 23, 23, and the base ends of each rear suspension arm 22, 22 are aligned with the axis in the longitudinal direction of the vehicle body. Elastic bushing 2 having
4 and 24, subframes 25 and 2 as vehicle body structural members are disposed front and rear in the left-right direction of the vehicle body.
5, and the strut hub 20 is supported by the vehicle body so as to be swingable in the vertical direction. A wheel hub 2 serving as a wheel support member that rotatably supports the strut hub 20 and the wheel 26.
7 is between the ball joint P and the first and second elastic bushings, as in the first embodiment.
It is connected by R ₁ and R ₂ . Furthermore, 2
8 is a stabilizer disposed in the left-right direction of the vehicle body on the rear side between the left and right wheels 27, 27, and the stabilizer 28 is connected to the control link 2 at both ends of its torsion bar portion 28a.
The arm portion 28 is rotatably supported by elastic bushings 30 and 30 attached to the vehicle body via 9 and 29, and the arm portion 28 is a bent end portion.
b, 28b are left and right wheel hubs 27,
It is connected to 27. The connecting portion 31 between the stabilizer 28 and the wheel hub 27 is
It is arranged at a lower position than the connection point of the ball joint P of the wheel hub 27 and at a higher position than the rotation axis (elastic bushings 24, 24) of the strut hub 20. In addition, in FIG. 2, 32 is a differential, and 33 is a drive shaft.

Therefore, also in this embodiment, the rotation axis of the strut hub 20 (elastic bushings 24, 24)
is the longitudinal direction of the vehicle body, the rotation axes (torsion bar portions 28a) of the stabilizer 28 are non-parallel to each other in the left-right direction of the vehicle body, and the wheel hub 27
Since the connecting portion 31 between the stabilizer 28 and the stabilizer 28 is located at a higher position than the rotation axis of the strut hub 20, the connecting portion 31 is forcibly rotated around the rotation axis of the strut hub 20 when bumping, and the stabilizer 28 A reaction force outward in the left and right direction will be generated. As a result, since the connecting portion 31 is located at a lower position than the connection point of the ball joint P of the wheel hub 27, the wheel hub 27 moves around the ball joint P due to the outward reaction force in the left and right direction of the stabilizer 28. The wheel attitude can be changed in reverse camber by rotationally displacing in the reverse camber direction.

FIG. 3 shows a third embodiment in which the present invention is applied to a Deion type rear suspension, in which 40 is a rocking member extending in the left-right direction of the vehicle body and having a rear axle inserted therethrough, which is provided separately from the drive shaft 41. Tension rods 4 extending in the longitudinal direction of the vehicle body are provided at both ends of the rear axle pipe 40.
The rear ends of 2, 42 are connected via elastic bushings 43, 43, and each tension rod 42, 4
The front end portions of the rear axle tubes 2 and 2 are connected to the vehicle body via elastic bushings 44, 44, and the rear axle tube 40 is supported by the vehicle body so as to be swingable in the vertical direction. Similarly, a ball joint P and first and second elastic bushes R ₁ and R ₂ are connected between the rear axle tube 40 and the wheel hub 46 as a wheel support member that rotatably supports the wheel 45. are connected by. Furthermore, 47 is a left and right wheel hub 46,
46, and is rotatably supported on the vehicle body by a torsion bar portion 47a via elastic bushings 48, 48.
arm portion 47b as a bent end portion of
47b is curved so as to expand rearward and outward, and the rear end portions of the arm portions 47b, 47b are connected to left and right wheel hubs 46, 46, respectively. Further, the connection portion 49 between the stabilizer 47 and the wheel hub 46 is located at a lower position than the connection point of the ball joint P of the wheel hub 46, and the rotation axis of the rear axle tube 40 (the elastic bushings 44, 4
4) It is located at a higher position. In addition, in FIG. 3, 50 extends in the longitudinal direction of the vehicle body and is connected to the rear axle pipe 4.
The leaf spring 51 on which 0 is mounted is a differential.

Therefore, in this embodiment, the wheel 4
5, the wheel hub 46 rotates upward along with the upward rotation of the rear axle tube 40, and the connecting portion 49 between the wheel hub 46 and the stabilizer 47 is also restrained and controlled by the upward rotation of the rear axle tube 40. The rotation axis of the rear axle tube 40 (elastic bushings 44, 44)
Forced to rotate around. At that time, the connecting portion 4
9 is located at a higher position than the rotation axis of the rear axle tube 40, the arm portion 47b of the stabilizer 47 is pressed inward to the vehicle body, and as a reaction force, the arm portion 47b of the stabilizer 47 is pushed outward in the left and right direction. A reaction force in the direction will be generated. As a result,
Similarly, since the connecting portion 49 is located at a lower position than the ball joint P, it is possible to rotationally displace the wheel hub 46 in the reverse camber direction around the ball joint P to change the wheel 45 in reverse camber. can.

Next, an optimal example of the arrangement of the ball joint P, the first and second elastic bushes R ₁ and R ₂ , and the arrangement of the stabilizer Q will be explained with reference to FIG.

Fig. 4 is a view of the wheel W on the rear right side of the vehicle body as seen from the left side (inside side) of the vehicle body, and in the horizontal (X axis) and vertical (Z axis) coordinates of the wheel center O reference 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.

The first elastic bushing _R1 is arranged so that its axis is inclined outward toward the rear of the vehicle, and the second elastic bushing _R2 is arranged such that its axis is inclined inward toward the rear of the vehicle. It is arranged like this. In addition, 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 for the above coordinates (X, Z), and the ball joint A rectangular coordinate system (L, M, N) is constructed with the center of P as the origin.

Furthermore, the mounting surface including the ball joint P and the first and second elastic bushes R ₁ and R ₂ is located in the YZ plane (vertical plane including the wheel center axis) of the coordinate system (X, Y, Z). , are arranged so that they are located on the inside of the vehicle body from the wheel center O in the Y-axis direction (wheel center axis), and on the outside of the vehicle body on the wheel contact surface.

In addition, the stabilizer Q is attached to the wheel hub H.
It is disposed further rearward in the left-right direction of the vehicle body and rotatably supported by the vehicle body, and the connecting portion J between the stabilizer Q and the wheel hub H is located rearward and at a lower position than the ball joint P. It is located at a higher position than the rotation axis of the swinging member (semi-trailing arm 1, etc.).
At the time of a bump, the connecting portion J is forcibly rotated around the rotation axis of the swinging member, and as shown in the YZ plane projection, the rotation trajectory L ₁ of the stabilizer Q and the rotation trajectory L ₂ of the coupling portion J are Due to the difference, a reaction force T is generated on the stabilizer Q in the left-right direction, diagonally outward, and downward.

Therefore, in this case, as described below, the wheel attitude at the time of a bump can be controlled to reverse camber and toe-in, and it is also possible to obtain a toe-in effect for other wheel acting forces. In other words, at the time of a bump, the horizontal outward component of the horizontal and diagonally outward reaction force T of the stabilizer Q
T ₁ generates a moment that rotates the wheel hub H counterclockwise around the L axis or N axis around the ball joint P, respectively.
Among these, the moment around the N axis causes the wheel hub H to rotate in the reverse camber direction around P, causing the wheel W to change in reverse camber, and the moment around the L axis causes the wheel hub H to rotate in the toe-in direction around P. The wheel W undergoes a rotational displacement and a toe-in change.

Furthermore, the vertical downward component force T ₂ of the reaction force T of the stabilizer Q generates a moment that rotates the wheel hub H clockwise around the M axis around the ball joint P, and the wheel hub H is rotationally displaced backward. . At that time, the axis of the first elastic bushing _R1 is arranged outward toward the rear of the vehicle body, and the axis of the second elastic bushing _R2 is arranged toward the rearward inward direction of the vehicle body, and in general, the rigidity of the elastic bushing is The wheel hub H is lower in the axial direction than in the direction orthogonal to the axial center and has a characteristic of being more easily elastically deformed in the axial direction.
As it rotates backwards around
Due to the elastic deformation of the second elastic bushings R ₁ and R ₂ , the rotation changes in the toe-in direction, and thus the wheel W
The toe-in change can be performed reliably and effectively in combination with the toe-in effect by the horizontal outward component force _T1 .

Since the lateral force S acts in the +Y direction with respect to the wheel grounding point, it acts as a moment force that rotates the wheel hub H counterclockwise around the L axis around the ball joint P. is rotationally displaced in the toe-in direction about P, and the wheel W changes in toe-in.

Brake force B is +X relative to the wheel grounding point
Therefore, by acting as a moment force that rotates the wheel hub H in the counterclockwise direction around the L axis around the ball joint P, the wheel W similarly changes in toe-in. At this time, the wheel hub H further rotates counterclockwise around the M axis around the ball joint P and tries to change toe-out. In order to prevent the first elastic bushing R ₁ in one quadrant from moving inward into the vehicle body, it is preferable to provide a stopper at the front end of the first elastic bushing R ₁ .

Engine braking force (engine braking force) E acts on the wheel center O in the +X direction, so it acts as a moment force that rotates the wheel hub H clockwise around the M axis around the ball joint P. , the wheel W undergoes a toe-in change in the same manner as in the case of the vertical downward component force T ₂ of the stabilizer Q.

Since the engine driving force K acts on the wheel center O in the -X direction, the wheel hub H
By acting as a moment force to rotate counterclockwise around the L axis around the ball joint P, the wheel W changes toe-in similarly to the case of the brake force B described above.

It should be noted that the present invention is not limited to the embodiments described above, but also includes various other modifications. For example, in the above embodiment, an example is shown in which the invention is applied to a semi-trailing type, a strut type, and a deion type rear suspension. This can also be applied to sion. 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 body constitutes the swinging member 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 arms. It is sufficient to connect the stabilizer to the second elastic bushings R ₁ and R ₂ and to the wheel support member.

In addition, it is sufficient that there is at least one elastic bushing, and the elastic bushing is elastically deformed to allow the wheel support member to undergo reverse camber change around the ball joint P due to the outward reaction force in the left and right direction of the stabilizer when bumping. All you have to do is do it.

As explained above, according to the rear suspension of the present invention, the ball joint and the elastic body are connected between the swinging member whose one end is swingably supported on the vehicle body and the wheel support member that rotatably supports the wheel. At the same time, the stabilizers arranged in the left-right direction of the vehicle are connected to the left and right wheel support members at their bent ends, and the joints between the wheel support members and the stabilizers are connected to the wheel support member. The connection point between the wheel support member and the stabilizer is placed at a lower position than the ball joint connection point of the swing member and at a higher position than the rotation axis of the swing member, so that the connection part between the wheel support member and the stabilizer rotates around the rotation axis of the swing member when bumping. It is configured so that it is forced to rotate and generates a reaction force outward in the left and right direction on the stabilizer, so the simple structure allows
When bumping, the wheel attitude can be effectively and reliably controlled to undergo a reverse camber change by the outward reaction force in the left-right direction of the stabilizer, and the running stability of the vehicle can be greatly improved.

Furthermore, since the reverse camber change of the wheel is performed by rotational displacement around the ball joint, the wheel is less likely to shift and has excellent behavioral stability, making the reverse camber effect more reliable.

Furthermore, since the above-mentioned reverse camber change of the wheel can be effectively and reliably performed using the rigid reaction force of the existing stabilizer, the advantage is that it not only improves driving stability but also simplifies the structure. It has the following.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the invention, FIG.
2 is a schematic perspective view showing the second embodiment, FIG. 3 is a schematic perspective view showing the third embodiment, and FIG. 4 is a schematic perspective view showing the ball joint and the first, second embodiment.
FIG. 7 is a schematic explanatory diagram showing a specific example of the arrangement structure of the second elastic body bush and the stabilizer. DESCRIPTION OF SYMBOLS 1... Semi-trailing arm, 2... Elastic bushing, 4... Wheel hub, 5... Wheel, 8... Stabilizer, 8a... Torsion bar part, 8b... Arm part, 11... Connection part, P
...Ball joint, _R1 ...First elastic bushing, _R2 ...Second elastic bushing, 20...Strut hub, 24...Elastic bushing, 26...
...Wheel, 27...Wheel hub, 28...Stabilizer, 28a...Torsion bar section, 2
8b... Arm part, 31... Connection part, 40... Rear axle tube, 44... Elastic body bushing, 45... Wheel, 46... Wheel hub, 47... Stabilizer, 49... Connection part.

Claims (1)

[Claims] 1. A rocking member whose one end is rockably supported on the vehicle body, a wheel support member that rotatably supports a wheel, and a rocking connection between the wheel support member and the rocking member about one point. an elastic bushing that connects the wheel support member and the swinging member; a stabilizer connected to a support member, the connection portion between the stabilizer and the wheel support member being at a lower position than a ball joint connection point of the wheel support member and higher than a rotation axis of the swinging member. When bumping, the connecting part between the stabilizer and the wheel support member is forcibly rotated around the rotation axis of the swinging member, generating a reaction force outward in the left-right direction on the stabilizer, which causes the wheel to move. A rear suspension for an automobile characterized by being configured to have a reverse camber change.