KR20030021476A - system for varying a steer specific property of an automotive vehicle - Google Patents

Abstract

PURPOSE: A device for varying a steering characteristic of a vehicle is provided to learn driving ability in accordance with each condition and make a driver cope with conditions well. CONSTITUTION: A device for varying a steering characteristic of a vehicle includes plural ground clearance-varying units varying the ground clearance between road surface and a vehicle body; a power-generating/supplying unit supplying driving source, to operate the ground clearance-varying units; and a control unit(22) selectively applying the power source generated from the power-generating/supplying unit among the plural ground clearance-varying units and inducing a change of the steering characteristic. The ground clearance-varying unit comprises an operating cylinder(10), a movable rod(12) to repeat elongation and contraction according to the working pressure, and a rolling wheel(14) to reduce friction with road surface. Thus, a change in ground clearance of the vehicle body is controlled.

Description

Vehicle for varying a steer specific property of an automotive vehicle

The present invention relates to a device for varying the steering characteristics of a vehicle, and more particularly, by artificially changing the traction between the road surface and the tire while driving so that the steering characteristics of the vehicle can be adjusted variably, thereby allowing the driver to vary the driving conditions. An apparatus for varying steer characteristics of a vehicle that enables training for the ability to respond effectively.

In general, the suspension system of the car is connected between the axle and the body so that the vibration or shock received from the road surface is not directly transmitted to the body while driving, thereby improving the ride comfort while preventing damage to the body and the loaded cargo. As an apparatus, it is composed of a chassis spring for mitigating an impact from a road surface, a shock absorber for controlling the free vibration of the chassis spring to improve ride comfort, a stabilizer bar for preventing rolling of the vehicle, and the like.

Here, the chassis spring to mitigate the impact from the road surface is a coil spring in the case of a passenger car, but in the medium-sized and commercial vehicles mainly use a leaf spring.

In addition, the suspension device may be classified into various types such as the McPherson type, the wishbone type, the trailing link type, and the multi-link type according to the shape of the suspension arm constituting the suspension device.

On the other hand, the most important of the performance check items for the driving stability of the vehicle is the under-steer or over-steer characteristics, such that the steering characteristics are slightly different for each vehicle, the steering characteristics of the suspension system It is also closely related to the characteristics.

In other words, the characteristic of the suspension system of the vehicle is to control the spring constant value of the suspension system and the damping force of the shock absorber to stabilize the behavior of the vehicle body that changes according to the change of the centrifugal force or inertial force of the vehicle while driving. There is a slight difference in each vehicle.

The understeer phenomenon is mainly caused when the stiffness of the front suspension is large or the traction between the road surface and the tire is small.

In addition, the oversteering phenomenon is mainly caused when the rigidity of the damping force of the rear suspension device is large or the traction force between the road surface and the tire is small.

That is, the understeer phenomenon and the oversteer phenomenon are changed according to the stiffness designed in each suspension device and the difference in the traction force changed between the road surface and the tire while driving.

However, in order to improve the driver's driving ability, the driving training must be repeated through a vehicle having various steer characteristics. Actually, improving the driver's driving ability through driving training through all the vehicles has many issues such as cost. The disadvantage is that it is practically impossible to consider.

Accordingly, the present invention is conceived in view of the above, by varying the ground height of the front and rear body to give an artificial change in the traction force generated between the road surface and the tire while driving to change the steering characteristics of the vehicle to change Steering characteristic variable device of a car that induces an artificial change to create an environment in which driving skills appropriate to each situation can be acquired, and thus to prepare a condition for improving driver coping ability. The purpose is to provide.

The present invention for achieving the above object is a number of ground level variable means for varying the ground height between the road surface and the vehicle body in the front / rear portion of the vehicle body, and a drive source required for the operation of the ground height variable means A power source generating / supply means for supplying and a control means for selectively applying a power source generated from the power source generating / supply means to the above ground level varying means to effect a change in the steer characteristics. do.

1 is a block diagram showing a device for varying the steering characteristics of the vehicle according to the present invention.

<Description of Symbols for Main Parts of Drawings>

10-operating cylinder 12-movable rod

14-wheel 16-hydraulic pump

18-Electronically Controlled Directional Valve 20-Hydraulic Pipeline

22-control unit

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating a vehicle suspension apparatus having a variable steering characteristic according to the present invention.

According to the present invention, as shown in the figure, the ground height is installed in each of the front and rear parts of the vehicle in appropriate places to change the ground height between the road surface and the vehicle body to vary the grip between the road surface and the tire The ground height varying means by selectively applying the variable means, the power source generation / supply means for supplying a drive source necessary for the operation of the ground height varying means, and the power source generated from the power source generation / supply means to the ground height varying means. And controlling means for controlling the operation of the means to effect changes in the steering characteristics including understeer characteristics and oversteer characteristics in performance on running stability.

Here, the ground height varying means is an operating cylinder 10 installed on the bottom of the front and rear portions of the vehicle, and the movable rod 12 for elongating and contracting in accordance with the operating pressure in the operating cylinder 10 And a rolling wheel 14 mounted on the lower end of the movable rod 12 to reduce friction generated therefrom upon contact with the road surface.

In addition, a mounting bracket 10a is attached to the operation cylinder 10 for coupling with the bottom of the front / rear side of the vehicle.

Further, the power source generation / supply means includes a hydraulic pump 16 for supplying and releasing hydraulic pressure in the operation cylinder 10 of the ground height varying means, and the operating pressure supplied from the hydraulic pump 16 to the front of the vehicle body. Electronically controlled directional control valves (18) for supplying selected ones of the operating cylinders (10) respectively installed at the rear / rear parts, and operations provided at the electronically controlled directional control valves (18) and the front and rear parts of the vehicle body, respectively. It consists of a hydraulic pipe 20 for communicating between the cylinder (10).

On the other hand, the control means is composed of a control unit 22 for controlling the operation of the hydraulic pump 16 and the electronically controlled directional control valve 18 to variably adjust the front and rear ground clearance of the vehicle.

Accordingly, the control unit 22 controls the operation of the hydraulic pump 16 and the electronically controlled directional control valve 18 while driving, thereby varying the ground clearance installed at the front and rear sides of the vehicle through the hydraulic pipeline 20. When the working pressure is applied in the working cylinder 10 of the means, the movable rod 12 movably installed in the working cylinder 10 is moved outwardly in the working cylinder 10 by hydraulic pressure. As a result, the ground clearance between the road surface and the car body changes.

At this time, the rolling wheel 14 installed at the lower end of the movable rod 12 reduces the friction caused when the contact with the road surface, and also reduces the lateral force transmitted to the movable rod 12 in accordance with the friction.

When the ground clearance between the road surface and the vehicle body is changed as described above, a change occurs in the steering characteristics of the vehicle. First, the operating pressure is applied to the operation cylinder 10 of the ground height varying means installed at the front vehicle body side during turning. When the front ground clearance is increased by supplying the stiffness, the traction force between the road surface and the tire decreases at the front side, and thus an understeer phenomenon occurs.

In addition, when the driving force is supplied to the operation cylinder 10 of the ground height varying means installed at the rear vehicle body side while the vehicle is turning while driving to raise the rear ground height, the traction force between the road surface and the tire is reduced at the rear side, resulting in an oversteering phenomenon. This will occur.

On the other hand, if the steering characteristics of the vehicle while driving as described above can be variably adjusted, it is possible to obtain the driving ability obtained through a vehicle having various steering characteristics as a single vehicle.

As described above, according to the apparatus for varying the steering characteristics of the vehicle according to the present invention, it is possible to artificially adjust the change in the ground height of the front and rear bodies of the vehicle, thereby giving a change in the traction force generated between the road surface and the tire while driving. By changing the steering characteristics of the vehicle, it is possible to enhance the driver's driving ability through appropriate training for the change in the steering characteristics.

In addition, since a single vehicle capable of changing the ground height of the front and rear bodies can be experienced through driving conditions of various vehicles having different steer characteristics, there is an economical advantage.

Claims (5)

A plurality of ground height varying means for varying the ground height between the road surface and the vehicle body at the front / rear side of the body, a power source generation / supply means for supplying a driving source necessary for the operation of the ground height variable means, and the power source generation And control means for selectively applying a power source generated from the supply means to the above ground level varying means to change the steer characteristics. The method of claim 1, The above ground height varying means includes an operation cylinder 10 installed on the bottom of the front and rear sides of the vehicle body, a movable rod 12 which repeats expansion and contraction in accordance with the operating pressure in the operation cylinder 10, and the operation thereof. Steering characteristics variable device of a vehicle, characterized in that made of a rolling wheel (14) mounted on the bottom of the rod 12 to reduce friction with the road surface. The method of claim 2, Steering characteristic variable device for a vehicle, characterized in that the operating cylinder (10) is provided with a mounting bracket (10a) for coupling with the front and rear bottom portion of the vehicle body. The method of claim 1, The power source generating / supply means supplies a hydraulic pump 16 for supplying a working pressure in the working cylinder 10 and a working pressure supplied from the hydraulic pump 16 to a selected one of the plurality of working cylinders 10. Steering characteristics of a vehicle, characterized in that it consists of an electronically controlled directional control valve (18) and a hydraulic pipe (20) for communicating between the electronically controlled directional control valve (18) and the plurality of operating cylinders (10), respectively. Variable device. The method of claim 1, The control means is a steering unit 22, characterized in that the control unit 22 for controlling the operation of the hydraulic pump 16 and the electronically controlled directional control valve 18 to variably adjust the front and rear ground clearance of the vehicle body. Variable device.