JPS60146708A - Rear suspension for automobile - Google Patents

Abstract

PURPOSE:To adjust and control a toe-in trend in rear wheels as well as to aim at the promotion of compatibility between straight forward stability and turning responsiveness, by making the hardness of elastic member installed in a supporting point of a suspension arm for rear wheels vary according to size of a steering angle. CONSTITUTION:A rear suspension 14 suspends each of symmetrical rear wheels 15L and 15R on a car body, and at a supporting point of a front side lateral link 18 among supporting points for a suspension arm, an elastic member 22 is filled up and tightly attached to space between the supporting point and a fulcrum shaft 21 attached to a car body. An oil leading passage 25 branched from an oil return passage 24 of a power steering mechanism 7 is interconnected to a hydraulic chamber 23 formed in the elastic member 22 via an interconnecting hole 26, while a control valve 29 is installed in position along the downstream of a branch point. A valve 29 is provided with a valve body 29 and a solenoid 29b, and in time of a steering angle being small, it widens a passage area but in time of being large, it throttles it, whereby hardness in the elastic member 22 is controlled according to size of the steering angle.

Description

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

(Prior Art) Conventionally, as disclosed in Japanese Utility Model Application Publication No. 58-18804, for example, as disclosed in Japanese Utility Model Publication No. 58-18804, as a rear suspension of an automobile, a lateral link with two trees at the front and rear where the rear wheels extend in the vehicle width direction with respect to the vehicle body has been used. It is known to be supported at a plurality of support points via a resuspension arm.

In this type of 4(y+) suspension, an elastic member is provided at at least one of the support points of the suspension arm, for example, the support point of the front lateral link, in order to improve straight-line stability. It is conceivable that when a lateral force or the like acts on the rear wheels, the rear wheels turn inward into the vehicle body (toe-in tendency) due to the deflection of the elastic member.

However, in this case, even when the steering wheel is turned sharply to park the car, etc., the elastic members, especially those in the rear 4 nose suspension on the opposite side of the turning direction, are affected by the cornering force as a lateral force acting on the wheel. By bending the helmet in the same way (folding the helmet), the rear wheel on the opposite side to the turning direction will face inside the vehicle body, that is, toward the turning direction.

As a result, turning responsiveness is impaired.

(Objective of the Invention) The object of the present invention is to make each of the elastic members provided at the support points of the υ spencer arm variable as described above, and to adjust the hardness of the elastic member according to the magnitude of the steering angle. By controlling the toe-in tendency of the rear wheels by changing the mI!!, it is possible to achieve both straight-line stability and turning responsiveness.

(Structure of the Invention) In order to achieve the above object, the structure of the present invention provides a rear suspension for an automobile in which a rear wheel is supported on a vehicle body via an arm at a plurality of support points. An elastic member with variable hardness is installed at each of the two support points, and a control means is provided to adjust and control the hardness of the elastic member.With this, when the steering angle is small, one of the rear wheels is - The toe-in tendency of the rear wheels is strengthened, and when the steering angle increases, the control means changes the angle of the elastic member to counteract the toe-in tendency of the rear wheels.

(Effects of the Invention) According to the present invention, the hardness of the elastic member provided at the support point of the arm supporting the rear wheels changes depending on the magnitude of the steering angle, and as long as the steering angle is small, The rear wheels tend to have a strong toe-in tendency, and when the steering angle is increased to make a sharp turn, there is almost no rear wheel toe-in tendency, effectively improving both straight-line stability and turning response depending on the driving condition. This makes it possible to provide a practically excellent automobile suspension A7.

(implementation@) Below 1. Embodiments of the present invention will be described based on the drawings.

Ru.

In FIG. 1, reference numeral 1 denotes a steering device that steers the left and right front wheels 21.2'R, and the steering side 1 includes a steering wheel 3 to be steered and a steering force of the steering wheel 3 in the width direction of the vehicle and in the left and right directions. ) reciprocating motion (converting and transmitting the binion 4a and the rack 4b, □ the left □ right sliding rod 5.5 whose base end is connected to each end of the rack 4b (7), and the two ends of each tie rod, t: 5.' A knuckle arm 6 whose other end is connected to the left and right front wheels 2L and 2R, respectively, is connected to the r tip of 5.
．． 6, and is configured to reciprocate the left and right tie rods 5.5 in the vehicle width direction in response to the steering operation of the steering wheel 3, thereby steering the left and right front wheels 2L and 2R left and right.

The steering device 111 also includes a power steering mechanism 7 for assisting the steering of the steering wheel 3. The power system 7 ring III structure 7 has a hydraulic cylinder 8 with a rack 4b as an operating rod, and in the hydraulic cylinder 8, a left-turning hydraulic chamber 8a and a right-turning hydraulic chamber 8b are integrally provided in the rack 4b. □It is partitioned (formed) left and right by a bismine 9. Each of the above-mentioned hydraulic chambers 8a; 8
b communicates through hydraulic passages 10a and 10b, respectively, to the controller 1 to the roll valve 11 that control the oil supply direction i15 to the hydraulic cylinder 8 and the oil pressure, and the controller 1 to the roll pulp 5, 11 A hydraulic pump 13 is connected via an oil supply passage 12. The control valve 11 detects the rotation of the pinion 4a and communicates the hydraulic pump 13 with the hydraulic chamber 8a diverted to the hydraulic cylinder 86h when the xfIJ wheels 2L and 2R are steered to the left (clockwise in the figure). , front wheel 2. Rightward steering of L and 2R (in the figure, counterclockwise fi
(1) When steering to the right, the hydraulic pump 13 is communicated with the right turning hydraulic chamber 8b of the hydraulic cylinder 8, and at the same time, the hydraulic pump i3 is connected to the right turning hydraulic chamber 8b.
The pressure is reduced to a pressure corresponding to the rotational force of the pinion 4a (that is, the steering force of the steering wheel 3). Thus, when steering the steering wheel 3, the power steering mechanism 7 is configured to assist the steering of the steering wheel 3 by supplying pressure oil to the hydraulic cylinder 8 and to move the tie rod 5.5 back and forth in the vehicle width direction. There is.

Reference numeral 14.14 denotes a rear suspension that suspends the left and right rear wheels 151.15R on the vehicle body, and each rear suspension 14 includes a wheel support member 16 that rotatably supports the rear wheels 15L and 15R, and a wheel support member 16 that rotatably supports the rear wheels 15L and 15R. Two front and rear lateral links 18' and 1'9, one end of which is rotatably connected to the wheel support member 16 and the other end of which is rotatably connected to the vehicle body (frame 17), are arranged in the longitudinal direction of the vehicle body. , a trailing rod 2 whose rear end is rotatably connected to the wheel support member 16 and whose front end is rotatably connected to the vehicle body.
0, and the rear wheel 151.15R is supported by the vehicle body at three planar support points via the lateral link 18.19, which is a suspension arm, and the trailing rod 20.

As shown in FIGS. 2 and 3, at the support point of the front lateral link 18 behind the support point of the suspension control arm in the rear suspension 14, there is a support shaft several times apart. 21 and the cylindrical connecting portion 18a of the lateral link 18 surrounding the outer periphery of the support shaft 21, an elastic member 22 made of rubber or the like is filled and fixed, and the rear wheel 15L
, 15R, when an external force such as a lateral force acts on the elastic member 2
2, the rear wheels 15L, 15R tend to toe-in toward the inside of the vehicle body.

In addition, hydraulic chambers 23 and 23 are formed by removing a portion of the elastic member 22 at the upper and lower positions sandwiching the support shaft 21 between the valve member 22 and the connecting portion 18a of the lateral link 18.
An oil introduction passage 25 branched from the oil return passage 24 in the hydraulic circuit system of the power steering mechanism 7 is connected to the inner hydraulic chamber 23.23 through a communication hole 26 provided in the support shaft 21. The hydraulic chamber 23
, 23, the hardness of the elastic member 22 increases. In FIG. 2, reference numeral 28 designates a cap screwed onto the end of the connecting portion 18a of the lateral link 18 to prevent oil introduced into the hydraulic chamber 28 from leaking to the outside.

Further, reference numeral 29 denotes a control valve installed downstream of the branch point (near the oil tank 30) of the oil return passage 24 and the oil introduction passage 25, and the control valve 29 controls the passage area of the oil return passage 24. a valve body 29a with adjustable throttle;
A solenoid 29b receives an output signal from a steering angle sensor 31 that detects the front and rear steering angles 2L and 2R from the rotation angle of the steering wheel 3, etc., and operates the valve body 29a,
By widening the passage area when the steering angle is small and narrowing it when the steering angle is large, it functions as a control means for controlling the hardness of the elastic member 22 according to the magnitude of the steering angle. There is.

Next, the upper rear suspension system 1 according to the present invention
The effects of item 4 will be explained.

When the steering angles of the front wheels 2L and 2R are small, the passage area of the oil return passage 24 in the hydraulic circuit system of the Barry steering mechanism 7 is not restricted by the control valve 29, and oil returns smoothly through the oil return passage 24. Therefore, the elastic member 22 and the lateral link 18 connected to the inside of the oil introduction passage 25 and communicating with the oil introduction passage 25 are connected to each other.
The hydraulic pressure in the hydraulic chambers 23, 23 between the elastic member 22 and the hydraulic chambers 23, 23 becomes lower, and as a result, the elastic member 22 becomes easier to deform toward the hydraulic chambers 23, 23, and its hardness decreases. Therefore, when an external force such as a lateral force is applied to the rear wheels 15L, 15R when driving straight or turning slowly, the elastic member 22 is easily bent, causing a large toe-in tendency in the rear wheels 15L, 15R. It is possible to improve straight-line stability.

On the other hand, when the steering angle of the front wheels 2L and 2R increases, the passage area of the oil return passage 24 is narrowed by the control valve 29, and the oil pressure in the hydraulic chamber 23.23 increases accordingly, so that the elastic member 22 hydraulic chamber 23.
Deformation toward the 23 side is restricted, and the hardness of the elastic member 22 increases. For this reason, when making a sharp turn with a large steering angle to park in a garage, etc., the rear wheel 15 on the opposite side of the turning direction
Even if a cornering force as a lateral force acts on rear wheels 15L and 15R, the rear wheels 15L. 15R is almost never directed into the vehicle body, that is, in the turning direction, due to the bending of the elastic member 22, so that turning responsiveness can be improved.

It should be noted that the present invention is not limited to the above-mentioned examples, but includes various other examples of food forms.

For example, in the above embodiment, an elastic member 22 with variable hardness is provided at the support point of the front lateral link 18 among the arm support points of the rear suspension 14, and the hardness of the elastic member 22 is adjusted by the control means (control valve 29) to adjust the steering angle. However, in the present invention, an elastic member with variable hardness is provided at the support point of the rear lateral link 19, and the hardness of the elastic member is controlled by a control means to control the hardness of the elastic member to be small when the steering angle is small and to be large when the steering angle is large. The opening may be made larger when the steering angle is small and smaller when the steering angle is large, or the opening may be configured by assembling both. The point is, when the steering angle increases, the rear wheel 15L.

What is necessary is to configure it so that the toe-in tendency of the 15R is weakened.

Further, the present invention is directed to the rear wheel 15L as in the above embodiment.

15R is supported by the vehicle body at three support points 11' via the lateral links 18, 19 and the trailing rod 20, or the rear wheels are supported by the vehicle body at multiple support points via arms (not limited to bus suspensions). Of course, the present invention can be similarly applied to various rear suspensions.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and Fig. 1 is a schematic diagram showing the overall configuration of the steering system and rear suspension during automatic operation, and Fig. 2 is a partially cutaway diagram showing the support points of the lateral links. The plan view and FIG. 3 are cross-sectional views taken along the line ■-■ in FIG. 2. 14...Rear suspension, 15L, 15R...
Rear wheel, 18.19... Lateral link, 20... Trailing rod, 22... Elastic member, 23... Hydraulic chamber, 29... Control pulp. Patent applicant: Toyo Kogyo Co., Ltd. 1 Figure 1112 Figure 8 Figure 3

Claims (1)

[Claims] (1) Is the rear wheel connected through the arm? ! Number 1? 1 in the rear suspension of a car supported by the car body at point j
．． At least one of the support points of the arm marked F is provided with an elastic member with a variable hard skin, and when the steering angle increases, - [the hardness of the valve distributing member is changed to A rear suspension for an automobile characterized by a control means for weakening the toe-in tendency.