JPS6261442B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rear suspension of an automobile.

(Prior Art) Conventionally, as a rear suspension for an automobile, as disclosed in Japanese Patent Application Laid-Open No. 54-153422, wheel supports that rotatably support the left and right rear wheels, respectively, and wheel supports arranged in the lateral direction of the vehicle body have been used. two vertically swingable arms that connect the front and rear parts of the wheel support to the inside of the vehicle; A coupling member that shares the force applied to the vehicle body in the longitudinal direction is known. Each of the above members is symmetrical in length, arrangement, etc. on the left and right sides of the vehicle body.

By the way, it is well known that it is preferable to make the steering characteristics of a car the same when turning to the right and to the left in order to improve maneuverability and driving stability. It is being

However, in conventional automobiles, steering problems occur due to imbalances in the vehicle weight and weight loads applied to the left and right wheels (front wheels or rear wheels), and differences in the angle between the drive shaft and the center axis of rotation of the wheels. Currently, the characteristics are different for right-hand turns and left-hand turns, so-called deflection characteristics, and it has not been possible to sufficiently improve maneuverability and running stability.

One way to solve this problem is to change the spring constant of the bushes provided on the vehicle body side connecting parts of the arms arranged in the lateral direction of the vehicle body in the rear suspension as described above, so that the spring constant of the bushings provided on the vehicle body side connection part of the arms arranged in the lateral direction of the vehicle body is changed on the left and right sides. A system has been proposed that corrects the deflection characteristics in the right or left direction by adjusting the amount of toe change due to lateral force (cornering force) acting on the wheels (see Japanese Utility Model Application Publication No. 141805/1983).
However, this method lacks practicality because it is difficult to finely adjust the amount of toe change by changing the spring constant of the bushing.

(Objective of the Invention) The object of the present invention is to adjust the amount of toe change due to bumps between the left and right rear wheels during cornering, instead of adjusting the spring constant of the bushings by changing the spring constant on the left and right sides as described above, by placing the bushings in the lateral direction of the vehicle body. By making the mounting angles of the arms asymmetric on the left and right sides and adjusting them, the deflection characteristics can be easily corrected while making the arms common.

(Structure of the Invention) In order to achieve the above object, the structure of the present invention includes a wheel support that rotatably supports each of the left and right rear wheels, and a wheel support that is arranged in the lateral direction of the vehicle body and that supports the front and rear wheels of the wheel support, respectively. Two arms that are connected inside the vehicle body and can swing in the vertical direction, and a connection that connects the wheel support body or the vicinity of the wheel support connection portion of the arm to the vehicle body and shares the force applied to the rear wheels in the vehicle body longitudinal direction. In the rear suspension of an automobile, which is made up of parts, by making the mounting angle of at least one of the above two arms with respect to the horizontal plane asymmetric on the left and right sides, toe change due to bumps between the left and right rear wheels during cornering can be avoided. The amount is made different, and the deflection characteristic in the right or left direction is canceled out by the difference in the amount of toe change.

(Effects of the Invention) Therefore, according to the present invention, it is possible to correct the amount of toe change caused by the bumps of the left and right rear wheels during turning to cancel the deflection characteristics. By making the steering characteristics the same for the left turn and the left turn, maneuverability and running stability can be greatly improved. Moreover, the above-mentioned toe change amount can be adjusted delicately and easily by making the mounting angles of the arms arranged in the lateral direction of the vehicle body asymmetrical on the left and right sides, which also impairs the commonality of the arms. Since there is no such thing, it is advantageous in terms of practical application.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

1 and 2 show a rear suspension of an automobile according to an embodiment of the present invention. The steering characteristics of this car are set to understeering characteristics, and the understeering characteristics have a greater tendency to understeering when turning left than when turning right; It is something that you have.

In FIGS. 1 and 2, 1a and 1b are wheel supports that rotatably support the left and right rear wheels 2L and 2R, respectively, and 3a and 3b and 4a and 4b are located near the left and right rear wheels 2L and 2R, respectively. The front and rear arms 3a, 3b and 4 are two front and rear bar-shaped arms arranged substantially parallel to the lateral direction of the vehicle body and each inclined downwardly outward from the vehicle body.
a and 4b, each of which has a base end connected to the vehicle body (subframe 6) via an elastic bushing 5 having an axis substantially parallel to the longitudinal direction of the vehicle body so as to be swingable in the vertical direction, and a distal end portion thereof. are rotatably connected to the front and rear portions of the wheel supports 1a, 1b via elastic bushes 7 having axes substantially parallel to the longitudinal direction of the vehicle body. The rear wheel 2 is connected so as to be swingable in the direction
Left and right suspension arms 8 that receive and share the lateral force applied to L and 2R in the length direction.
a and 8b.

Further, reference numerals 9a and 9b are tension links as connecting members disposed in the longitudinal direction of the vehicle body, and the front end portions of each of the tension links 9a and 9b are connected to the vehicle body B.
The rear end portions are rotatably connected to the lower portions of the wheel supports 1a and 1b via elastic bushes 10 and 11, respectively, which have axes substantially parallel to the lateral direction of the vehicle body, and are rotatably connected to the lower portions of the wheel supports 1a and 1b. It is provided to receive and share the force applied in the longitudinal direction of the vehicle body in the longitudinal direction.

Then, the four arms 3a, 3b, 4a,
The mounting angles α ₁ and α 2 of the rear arms 4a and 4b with respect to the horizontal plane among the rear arms _4b are the same as the front arms 3a and 3.
b is set larger than the mounting angle β with respect to the horizontal plane, and between the rear arms 4a and 4b, the mounting angle α 1 of the left arm 4a is set to be larger than the mounting angle α ₁ of the right arm 4b.
The mounting angle of the left and right suspension arms 8a and 8b is set to be larger than α ₂ (that is, the size relationship is α ₁ > α ₂ > β), and the left and right suspension arms 8a and 8b are asymmetrical, so that the left and right rear wheels are The amount of toe change due to bumps 2L and 2R is configured to be different so as to cancel the leftward deflection characteristic of the vehicle.
Incidentally, 12 is a strut for cushioning the lifting and lowering of the rear wheels 2L and 2R.

Next, to explain the effects of the above embodiment, when a car turns, the centrifugal force causes the car body to tilt to the side opposite to the turning direction, and the suspension arm 8a or 8b on the tilted side Two front and rear arms 3a, 4a or 3 as constituent members
The rear wheels 2L or 2R bump while the wheels b and 4b rotate upward about their respective vehicle body side connecting portions (elastic bushings 5) as center points.

In this case, of the two front and rear arms 3a, 4a or 3b, 4b, the front arm 3a or 3
The mounting angle β with respect to the horizontal plane of b is the rear arm 4.
Since the attachment angle α ₁ or α ₂ of the front arm 3a or 4b with respect to the horizontal plane is smaller than and the wheel support body 1a or 1b will be largely displaced inward from the vehicle body,
The rear wheel 2L or 2R changes to the toe-in side due to the bump. Also, the amount of toe-in change of the rear wheels 2L and 2R is determined by the following equation: Among the arms 4a and 4b of the rear wheels, the mounting angle α ₁ of the left arm 4a is the same as that of the right arm 4b.
Since there is a larger difference between the mounting angle α of the front arm _3a and the mounting angle β of the front arm 3a, the amount of toe-in change of the left rear wheel 2L is larger than the amount of toe-in change of the right side. Therefore, the grip force of the left rear wheel is greater when turning to the right than when turning to the left, the cornering power is greater, and the understeer characteristics are stronger when turning to the right.

In this way, the difference in toe-in change due to the bump between the left and right rear wheels 2L and 2R is set in advance to cancel the leftward deflection characteristic of the vehicle itself, so it changes the understeering characteristic of the vehicle when turning left. This can be made the same for both right-turning and right-hand cornering, thereby improving maneuverability and running stability when turning.

Moreover, the difference in the amount of toe-in change described above is determined by how much larger the mounting angle α ₁ of the left arm 4a of the rear arms 4a and 4b is set than the mounting angle α ₂ of the right arm 4b. Therefore, the adjustment can be made delicately and easily, which is advantageous in practice.

Furthermore, since the lengths of the rear arms 4a and 4b are not different in any way, the arms 4a and 4b are not different in length.
A and 4b can be made common, and implementation can therefore be further facilitated.

It should be noted that the invention is not limited to the above embodiments, but includes various other modifications.
For example, in the above embodiment, the mounting angles α ₁ and α ₂ of the rear arms 4a and 4b with respect to the horizontal plane were made asymmetric on the left and right sides in order to cancel the deflection characteristics of the automobile. , 3b with respect to the horizontal plane can be made asymmetrical on the left and right, or the two arms 3a, 3b, 4a, 4b in the front and rear can be
The mounting angles of the left and right may be made asymmetrical, and the point is that due to the asymmetry, the amount of toe change caused by bumps between the left and right rear wheels 2L and 2R during cornering is made different, and even with that difference. Therefore, it is only necessary to configure the structure so as to cancel out the deflection characteristics of the automobile.

Further, in the above embodiment, the present invention was applied to a rear suspension of an automobile having a leftward deflection characteristic, but the rightward deflection characteristic, that is, the rightward turning is better than the leftward turning. Of course, the present invention can also be similarly applied to the rear suspension of an automobile, which has a characteristic of having a large tendency to understeering.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a plan view, and FIG. 2 is a rear view as seen from the rear of the vehicle body. 1a, 1b...wheel support body, 2L, 2R...rear wheel, 3a, 3b, 4a, 4b...arm, 9a,
9b...Tension link, α ₁ , α ₂ , β...
Mounting angle.

Claims (1)

[Claims] 1. A wheel support that rotatably supports each of the left and right rear wheels, and two arms that are arranged in the lateral direction of the vehicle body and that are swingable in the vertical direction that connect the front and rear parts of the wheel support body to the inside of the vehicle body, respectively. and a connecting member that connects the wheel support or the vicinity of the wheel support connection portion of the arm to the vehicle body and shares the force applied to the rear wheels in the vehicle body longitudinal direction. at least 1 of them
The mounting angle of the arm with respect to the horizontal plane is asymmetric on the left and right, and the toe change amount due to bumps on the left and right rear wheels during turning is configured differently so that the deflection characteristics in the right or left direction are canceled out. An automobile rear suspension characterized by a