JPS6060018A - Front suspension for automobile - Google Patents

Abstract

PURPOSE:To solve a problem of difference in steering characteristics at both sides, by making each setting position of tie rod and a suspension arm differ at both sides, in case of a front suspension being different in symmetrical steering charateristics for an engine horizontal type FF car or the like. CONSTITUTION:A front suspension attaches each of wheel support members 2a and 2b rotatably supporting symmetrical front wheels 1a and 1b to a car body 4 free of rocking motion in vertical directions by means of each of suspension arm 3a and 3b extending in a lateral direction of the car body, while it is supported on the car body 4 via suspension struts 5a and 5b. In addition, an interval be- tween each knuckle arm and a steering mechanism 6 installed in each of members 2a and 2b is coupled with tie rods 7a and 7b. In this case, vertical direction distances ha and hb between a setting point of these tie rods 7a and 7b to the knuckle arm and a setting point of each of arms 3a and 3b to these wheel support members 2a and 2b is made to differ in a direction of negating the difference between steering characteristics at both sides.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides an lB'l front suspension for an automobile.
f le. In particular, the invention relates to a front suspension and steering system combination for a motor vehicle.

(Prior art) For example, in a front-engine front-wheel drive vehicle, if the engine is installed sideways, the center of gravity of the power unit, including the transmission mechanism, will be deviated laterally from the central axis in the longitudinal direction of the power unit, and the steering The load on the front wheels rises on both sides. Even in rear-drive cars, which are often used with seven passengers, the front wheel loads generally differ between the left and right wheels. If there is a difference in the left and right front wheel loads in this way, the sum of the cornering forces acting on the left and right wheels during a turn will be different when turning to the right and when turning to the left, resulting in a difference in the left and right steering characteristics. occurs. In order to solve such problems,
-f'i in No. 141805.

A structure has been proposed in which the elasticity of the rubber bushings used to attach the suspension arms of the front wheels to the vehicle body are different between the left and right sides to offset the difference in steering characteristics between the left and right sides. However, with this structure, when the elasticity of the rubber constituting the rubber bushing changes due to aging, etc., the desired effect cannot be achieved.

(Object of the Invention) In view of the above points, the entire purpose of the present invention is to provide a highly reliable mechanism that can cancel out the difference in left and right steering characteristics.

(RF# composition of the invention) In order to achieve two objects, the present invention has the following configurations: 1. The front suspension of an automobile according to the present invention extends in the lateral direction of the vehicle body on each side of the vehicle body, and has one end attached to the vehicle body. S? A wheel support member rotatably attached to the other end of the suspension arm and rotatably supporting the front wheels of the automobile, and a suspension strut whose lower end is fixed to the wheel support member and whose upper end is rotatably attached to the vehicle body. It consists of a tie rod that connects the knuckle arm provided on the wheel support member to the steering mechanism of the automatic garage, and the steering characteristics of the left and right sides are different. The vertical distance from the attachment point to the wheel support FIBU is different between the left and right sides so as to cancel out the difference in steering characteristics between the left and right sides. To explain the principle of the present invention with reference to the drawings, in the kite 1 drawing, the right front wheel 1a and the left full front wheel 1b are respectively connected to the wheel support member 2.
It is rotatably supported by a and 2b. Wheel support member 2
a bZbI''i, BU is rotatably attached to the outer ends of the suspension arms 3a, 3b extending in the direction of the body's physical strength,
Inner end 1d of suspension john arms 3a, 3b Vehicle body 4
K is installed so that it can swing vertically. Further, the lower ends of the wheel supports M4st2a, 2bKu and the suspension struts 5a, 5b are fixed, and the upper ends of the suspension struts 5a, 5b are rotatably attached to the vehicle body 4. Wheel support part U2a.

Although not shown in detail in FIG. 1, 2bK is provided with a knuckle arm, and a tie rod 7a is connected between this knuckle arm and the steering mechanism 6.

7b is connected. This type of length suspension is called a strut type, and is designed to prevent bumps on the wheels,
Steering interference occurs during rebound. That is, referring to FIG.

When the wheel bumps and displaces upward from the position shown by the solid line, suspension injection arm 3a Id vehicle body 4 (7)
It swings upward at the position ridge shown by an imaginary line around the attachment point. Along with this rocking, the suspension strut 5a
is also displaced from the position shown by the solid line to the position shown by the imaginary line, and at the same time, the tie rod 7a also swings upward. At this time, if the steering angle of the wheels is maintained constant, the attachment point 8 of the tie rod 7a to the wheel support member will not move along the arc centered on the swing center 9, but will be at a point deviating from the arc. It will reach 8AK. However, since the tie rod 7a cannot be expanded or contracted, the attachment point actually moves along an arc centered on the swing center 9 and reaches the point 8B.
The wheels will be rotated by an angle corresponding to the distance between 88 and 88 in a direction that increases or decreases the steering angle. In other words, the steering angle of the wheel is changed when the wheel bumps.

This causes so-called steering interference. This steering interference also occurs during rebound when the wheels are displaced downward,
The magnitude and direction of steering interference are controlled by the vertical distance ha between the attachment point of the tie rod to the knuckle arm and the attachment point of the suspension arm to the wheel support member. The present invention focuses on this point and calculates the vertical distance ha.

By enclosing the hb on the left and right sides, the difference in steering characteristics between the left and right sides, which is inherent in automobiles, is canceled out.

(Effects of the Invention) As described above, in the present invention, the vertical distance between the attachment point of the tie rod to the knuckle arm and the attachment point of the suspension arm to the wheel support member is not the same on the left and right sides. The difference in distance in the vertical direction is a direction that cancels out the difference in steering characteristics between the left and right steering wheels, which is inherent in an automobile, so that it is possible to eliminate the difference in steering characteristics between the left and right sides in a comprehensive manner. Furthermore, since there is no need to rely on the elastic modulus of the rubber bushing to cancel out the difference in left and right steering characteristics, a highly reliable mechanism can be obtained.

(Example) When looking at FIG. 5 and FIG. 4, it is found that the right front wheel 18F'
! , the wheel support member 2aK is rotatably supported, and the left front wheel 1b is similarly rotatably supported by the wheel support member 2b. In the following, since the structures on the left and right are almost symmetrical, only the mechanism on the right will be explained, and the corresponding parts of the mechanism on the left will be shown with the same reference numerals as those on the right, and the subscript "a" will be replaced with "a" on the right. omitted.

An arm lla is formed on the wheel support member 2a, and the outer i of a suspension arm aa is rotatably connected to the tip of this arm lla via a wall joint 128K. The suspension arm 3a is an A-shaped arm extending in the lateral direction of the vehicle body, and its inner end is connected to the storage body 4 through rubber bushes 10 as 11 aK at two points separated in the longitudinal direction of the vehicle body.

Referring to FIG. 3, an arm 21a extending diagonally upward is formed on the wheel support member 2a, and the lower end of the one-length swing strut 5a is fixed to the tip of the arm 21a. The upper end of the suspension strut 5a is attached to the vehicle body 4 before rotation.

A knuckle arm 15a is provided on the wheel support part @2a so as to extend diagonally rearward, and the tip of this knuckle arm 15a is connected to the opposite end of the tie rod 7a. The inner end of the tie rod 7a is connected to one end of the steering slide 6. In this example, the steering end 6 is of the rack Φ pinion type, and the steering shaft 20 is self-fed.
It is connected to a steering ring wheel (not shown) of d+ifL. In Figure 6, the tie rod 7a on the right 1111
The center C of the joint connecting to the knuckle arm 15a
1, suspension arm 3 a ft wheel support member 2 a (connected to D arm 118)
12a and the center C2 is the left f111
smaller than the corresponding distance applied to the suspension.

As shown in the example, the tie rod is located behind the wheel center [, l
), suspension (suspension arms 3a, 3b (!): When the tie rods 7a, 7b are both approximately horizontal, steering interference tends to understeer in both bumps and rebounds, but the magnitude of the steering interference is as described above. Under the relationship of vertical distance, turning to the right will be stronger than turning to the left. In other words, turning to the right will have a stronger tendency to understeer. Therefore, when turning to the left, turning to the right will If this mechanism is adopted for a car that exhibits a stronger understeer tendency than when turning left or right, or a car that exhibits a stronger oversteer tendency when turning right or turning left than when turning left, it is possible to offset the difference in steering characteristics between the left and right sides. .

FIG. 5 shows another embodiment of the present invention. In this example, the tie rod 15b is 158% wheel support member 28%.
Projecting forward from 2b, tie rods 7a and 7b are ^11
It is located forward of the center of the unicycle 8% lb. In this arrangement, steering interference produces a tendency to oversteer, but the vertical distance between the attachment point of the tie rod to the knuckle arm and the attachment point of the suspension end to the wheel support member is different on the left and right sides. As a result, the difference in left and right steering characteristics can be canceled out, as in the %01T example.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view of a front suspension illustrating the principle of the present invention, Fig. 2 is a schematic diagram illustrating the principle of steering interference, and Fig. 6 is a rear view of a front suspension illustrating an embodiment of the present invention. FIG. 4 is a plan view thereof. 1a% lb...Front wheel%2a, 2b...Wheel support part 4J, 38% 3b・Fist/suspension arm, 5
a15b... Suspension strut, 6... Steering machine (1, 7a, 7b... Tie rod patent applicant Toyo Koryo Co., Ltd. Figure 1 Figure 5

Claims (1)

[Claims] A suspension arm extending in the lateral direction of the vehicle body on each side of the vehicle body and having one end attached to the vehicle body button so as to be swingable in the vertical direction, and rotatably attached to the other end of the suspension arm to rotatably support the front wheels of the automobile. a wheel support member;
It consists of a suspension strut whose lower end is fixed to the wheel support member and whose upper end is rotatably attached to the vehicle body, and a tie rod that connects the knuckle arm provided on the wheel support member to the steering mechanism of the vehicle, and the suspension strut controls the left and right steering characteristics. In the front suspension of an automobile, where there is a difference in steering characteristics, the vertical distance between the attachment point of the tie rod to the knuckle arm and the attachment point of the suspension arm to the wheel support member influences the difference in left and right steering characteristics. The front suspension of a car is characterized by being different on the left and right sides.