JPH09109636A - Suspension of automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suspension of an automobile, able to obtain the large wheel stroke without enlarging a component, and having few change of the wheel alignment. SOLUTION: A watt link mechanism 1 comprizes a first arm 2 and a second arm 3 arranged in parallel, and a third arm 4 for connecting both arms 2, 3 to each other is interposed between a body and a wheel 5 so that the rotational axial direction may be parallel to the car width direction. The first arm 2 and the second arm 3 are rotatably connected to a frame 6 of a body, and an approximately linear motion part of the third arm 4 is rotatably connected to a guide bracket 9 vertically movably attached to a guide post 11 fixed on the body side. A wheel bracket 14 for supporting the wheel 5 is attached to the guide bracket 9 through a king pin 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle suspension, and more particularly to a suspension suitable for a vehicle which causes a large change in vehicle height.

[0002]

2. Description of the Related Art An automobile suspension is a device that connects a body and a wheel, and includes a spring that reduces the impact received from the road surface while driving, a shock absorber that controls the free vibration of the spring to improve riding comfort, and a rolling car. It is composed of a link mechanism that controls various types, and various types are applied according to the vehicle type.

[0003]

In the case of conventional general suspensions applied to automobiles, especially passenger cars,
When the wheel moves up and down due to bound and rebound, the wheel alignment changes accordingly, affecting running stability. Generally, the maximum allowable vertical movement of the wheel, that is, the wheel stroke, is set to a maximum of 200 mm on the front side and a little less than 250 mm on the rear side. If you try to obtain a larger wheel stroke than the above, the change in wheel alignment will be large and you will not be able to run stably, or the components of the suspension will become large and the tread will increase, the installation space will expand etc. There is a problem with the point.

The present invention has been made in view of the above problems, and it is an object of the present invention to obtain a large wheel stroke without increasing the size of the components and to change the wheel alignment. The goal is to provide a car suspension that is rare.

[0005]

In order to solve the above problems, the present invention takes the following means. That is, claim 1
Of the invention is a suspension of an automobile, wherein a watt link mechanism including a first arm, a second arm, and a third arm connecting the both arms to each other is provided. The first arm and the second arm are rotatably connected to the body side so as to be parallel to
It is characterized in that the approximate linear motion part of the arm is rotatably connected to the wheel side.

According to the invention of claim 1, which is configured as described above, the wheel strokes up and down in an approximate linear motion. Therefore, compared with the conventional link type suspension, the wheel stroke can be made large for the arm length, and the wheel alignment change can be made almost zero.

According to a second aspect of the present invention, in the vehicle suspension according to the first aspect, a guide post is provided for guiding the wheel so as to linearly move in the vertical direction. According to the invention of claim 2 configured as described above, the guide post secures a smooth vertical movement of the wheel and supports a lateral load applied to the wheel.

According to a third aspect of the present invention, in the automobile suspension according to the second aspect, the number of the wheel guides is two, and one wheel guide is arranged one behind the other with the center of the wheel interposed therebetween. Claim 3 constituted in this way
According to the invention, since a space is secured between the left and right wheel centers, it is possible to adopt a mechanical drive system as the wheel drive.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. First, a first embodiment will be described with reference to FIGS. The suspension according to the first embodiment is an independent suspension system applied to the front side, FIG. 1 is an overall perspective view showing the suspension for one wheel, and FIG. 2 is a view taken in the direction of arrow A in FIG. Yes, FIG. 3 is a schematic diagram of the watt link mechanism.

The suspension connecting the body and the wheel 5 (front wheel) is mainly composed of the watt link mechanism 1. The watt link mechanism 1 has a first arm 2 and a first arm 2 which are arranged in parallel with each other with a predetermined space. Two arms 3 and a third arm 4 for connecting the two arms 2 and 3 to each other are comprised of three arms.

In the watt link mechanism, as shown in the schematic view of FIG. 3, the rotation centers of the first arm 2 and the second arm 3 are set to a and d, respectively, and the first arm 2 and the second arm of the third arm 4 are set. When the connection points with 3 are b and c, respectively, and when the p point is set on the third arm 4 so that the distance ab: cd = pc: pb, the first arm 2 and the second arm 3 respectively If you rotate around the points a and d as shown by the dotted line, p
The point moves approximately linearly within a limited range.

In this embodiment, however, the above-mentioned watt link mechanism 1 is installed between the body and the wheel 5 so that the rotation axis thereof is parallel to the vehicle width direction. That is, the points a and d, which are the base end portions of the first arm 2 and the second arm 3, are rotatably attached to the bracket 7 fixed to the frame 6 of the body via the pins 8, respectively. The points b and c, which are the tips of the arms 2 and 3 are attached to the third arm 4 by the pin 2 respectively.
It is rotatably connected via a and 3a, and the point p on the third arm 4 is rotatably attached to the guide bracket 9 via the pin 10.

The guide bracket 9 is formed in a substantially Z shape, and is vertically movably fitted through a linear slide bearing 9a to a cylindrical guide post 11 whose upper end portion is arranged substantially upright. Both upper and lower ends of the guide post 11 are fixed to the body side via brackets 12. Therefore, a deviation in the front-rear direction occurs between the guide bracket 9 that is vertically moved up and down along the guide post 11 and the watt link mechanism 1 that performs an approximate linear motion. This deviation is caused by the first arm. A rubber bush 13 interposed at the center of rotation of either the second arm 2 or the second arm 3.
(In the figure, the case of the first arm 2 side is shown).

On the outer surface side of the guide bracket 9, a wheel bracket 1 as a support member for supporting the wheel 5 is provided.
4 are arranged. The wheel bracket 14 is formed in a substantially U shape, and the upper and lower portions thereof are the kingpins 1.
It is attached rotatably at the required tilt angle by 5,
It is possible to steer the wheel 5 by adding an external input. Further, the wheel 5 is independently driven by a hydraulic motor 16 attached to the steering bracket 14.

The hydraulic cylinder 17 vertically disposed between the body and the second arm 3 has its base side and rod tip end rotatably connected to the body and the second arm 3, respectively. By providing an accumulator (not shown) on the circuit connected to the hydraulic cylinder 17, the hydraulic cylinder 17 serves as a shock absorber. When the hydraulic cylinders 17 are used instead of the normal springs and shock absorbers as shock absorbers, sensors for vehicle height and load are attached to each wheel, and the hydraulic cylinders 17 are connected by servo valves based on the information from the sensors. By controlling, it becomes possible to reduce the force transmitted from the road surface to the vehicle body, and to adopt an active suspension that keeps the vehicle body posture substantially parallel to the road surface.

In the first embodiment configured as described above, the watt link mechanism 1 is adopted as the suspension of the automobile, and the guide post 11 allows the wheel 5 to move.
Is configured to move linearly up and down, the change in wheel alignment due to the vertical stroke of the wheel can be made almost zero.

Further, by adopting the watt-link mechanism 1 which makes an approximate linear motion, the wheel stroke is more than double, that is, about 500 mm, without making the components large in size, as compared with an arm type suspension which makes an ordinary circular motion. Therefore, it is possible to provide a suspension that is suitable for running on an extremely bad road surface such as a mountainous area where undulations are severe. The arm rigidity of the watt link mechanism 1 opposes the input load in the front-rear direction during traveling, and the guide post 1 applies to the input load in the left-right direction (so-called lateral force).
Compete with a rigidity of 1.

Further, since the wheel alignment is inevitably determined by the inclination angle of the guide post 11 and the center of rotation of the first and second arms 2 and 3 of the watt link mechanism 1 with respect to the frame 6, the wheel alignment is required. Alignment adjustment is not required, which leads to improved assembly.
Further, since the hydraulic cylinder 17 can be used for buffering and adjusting the vehicle height, traveling on an extremely bad road surface becomes easier. Further, since the hydraulic cylinder 17 is connected to the second arm 3 (or the first arm 2), the cylinder length can be shortened as compared with the case where the hydraulic cylinder 17 is connected to the guide bracket 9.

Next, a second embodiment of the present invention will be described with reference to FIG. In the watt-link type suspension according to the first embodiment described above, because the guide posts 11 are arranged between the left and right wheel centers, when a mechanical drive system is adopted to drive the wheels, the drive shaft is arranged. Can not.

In view of this, in the second embodiment,
Two guide posts 11 are provided, and one guide post 11 is provided at each of the front and rear so as to sandwich the wheel center.
The other parts are configured in substantially the same manner as the first embodiment described above. In this case, since the two guide posts 11 need to be parallel to each other, one guide post 1
It is desirable to correct the parallelism by fixing one end of 1 to the frame side via a rubber bush (not shown).

The base end of the guide bracket 9 is directly fitted to the two guide posts 11 via the linear slide bearings 9a so that the guide bracket 9 can move up and down, and the third arm 4 of the watt link mechanism 1 and the pin. It is rotatably connected by 10, and its lower side is formed in an arch shape so as to straddle the wheel center.

According to the second embodiment configured as described above, since a space is formed between the left and right wheel centers, a drive shaft (not shown) is arranged by utilizing this space. The wheel 5 can be mechanically driven. However, as in the first embodiment, it is also possible to adopt a drive type using the hydraulic motor 16. In addition, in the second embodiment,
The use of two guide posts 11 is also effective in increasing the rigidity against an input load in the left-right direction.

The present invention is not limited to the illustrated embodiment, but can be appropriately changed within the scope not departing from the gist thereof. For example, a general spring is used instead of the hydraulic cylinder 17 for buffering. A shock absorber consisting of a shock absorber and a shock absorber may be adopted. In addition, in the second embodiment, the wheels 5 may be configured to be steerable as in the first embodiment.

Further, in the first embodiment, the rubber bush 13 absorbs the displacement in the front-rear direction due to the approximate linear movement, but it is approximated by making the guide post 11 movable in the front-rear direction. A structure that absorbs a deviation in the front-back direction due to the linear movement may be adopted. For example, bracket 1
When mounting the guide post 11 on the bracket 2, a long hole is formed in the bracket 12 so that the inserted guide post 11 can move only in the front-rear direction, and a rubber bush is interposed between the guide post 11 in the long hole. Just do it.

The guide posts 11 described in the first and second embodiments are not indispensable for obtaining a large wheel stroke, and the pin for connecting the watt link and each arm and the connecting portion thereof are not required. If you give it enough rigidity,
The guide post 11 may be omitted and the pin rigidity may be used to counteract the input load (lateral force) in the left-right direction. In this case, in the first embodiment, the gobush 13 arranged for absorbing the displacement in the front-rear direction due to the approximate linear movement is
Can be omitted.

[0026]

As described in detail above, according to the invention of claim 1, a larger wheel stroke can be obtained as compared with the conventional suspension, and the components of the suspension do not become large. It can be easily secured. In addition, it is possible to suppress the wheel alignment change to almost zero after obtaining a large wheel stroke, which improves traveling stability.

According to the second aspect of the present invention, it is possible to ensure stable linear vertical movement of the wheel by the guide post, and it is possible to easily obtain the rigidity against the load from the left and right directions. According to the invention of claim 3, the degree of freedom in determining the drive system of the wheel can be obtained, and the rigidity with respect to the lateral load input from the wheel can be easily increased.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a suspension of an automobile according to a first embodiment.

FIG. 2 is a view taken in the direction of arrow A in FIG. 1;

FIG. 3 is a schematic view of a watt link mechanism.

FIG. 4 is a perspective view showing a suspension of the automobile according to the first embodiment.

[Explanation of symbols]

 1 ... Watt link mechanism 2 ... 1st arm 3 ... 2nd arm 4 ... 3rd arm 5 ... Wheel 9 ... Guide bracket 10 ... Guide post 14 ... Wheel bracket

Front Page Continuation (72) Inventor Shunichi Shibasaki 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd.

Claims (3)

[Claims] 1. A watt link mechanism including a first arm, a second arm, and a third arm connecting the both arms to each other, and a rotation axis direction of the watt link mechanism is parallel to a vehicle width direction. Interposing between the body and the wheel,
A vehicle suspension in which the first arm and the second arm are rotatably connected to the body side, respectively, and the approximate linear motion portion of the third arm is rotatably connected to the wheel side. 2. The vehicle suspension according to claim 1, further comprising a guide post for guiding the wheel so as to linearly move in the vertical direction. 3. The vehicle suspension according to claim 2, wherein the number of the guide posts is two, and one guide post is provided on each side of the wheel center.