JPS62205885A - Steering gear for car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to a vehicle steering system capable of improving steering performance.

b. Prior Art A straddle-type tricycle or four-wheel vehicle using low-pressure tires is known as a vehicle for traveling on rough terrain. Among these, some vehicles with two front wheels, such as four-wheeled vehicles, use independent suspension suspension for the front wheels, and in this case, a center arm type steering link mechanism is used to steer the front wheels. There is.

As shown in FIGS. 3 and 4, this steering mechanism includes a knuckle arm 101 of 100 front wheels and a steering arm 103 provided on a steering shaft 102.
are linked together via a tie rod 104,
The front wheels 100 are steered by rotating the steering shaft 102.

C3 Problems to be Solved by the Invention According to the steering mechanism configured as described above, in order to make the turning angles of the left and right wheels the same when the steering shaft is rotated, the ends of the left and right tie rods 104 on the steering shaft side The parts are supported by the same shaft 105.

On the other hand, since the steering shaft 102 is provided with a constant inclination in the longitudinal direction, the support shaft 105 of the tie rond 104 is also provided with a similar inclination.

This inclination is caused by the vertical movement of the wheels 100 due to the vibration of the vehicle body.
There is usually a difference of 30 degrees from the trajectory of For this reason, front wheel 1
00 runs onto a step such as a stone, because the two tie rods 104 have different inclinations and lengths, the wheels 10
0 will naturally turn the steering wheel, resulting in a decline in maneuverability.

In addition, the inclination of the kingpin when the kingpin method is adopted for supporting the wheel, or the inclination of the shaft connecting two ball joints when the ball joint method is adopted,
The inclination of the support shaft 105 of the tie rod 104 is different. Therefore, the tie rod 1 connected to the upper side of the support shaft 105
04 and the tie rod 104 connected to the lower side, the length is slightly different, so the rotation angle of the steering shaft 102 and the steering angle of the left and right wheels 100 do not necessarily correspond, resulting in a decrease in maneuverability. I was invited.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle steering system capable of solving the problems of the prior art described above and improving steering performance.

d. Means for Solving the Problems In order to solve the above problems, the present invention provides a vehicle for use in which a knuckle arm for steering the front wheels and a steering arm supported by a steering shaft are connected via tie rods. In the steering device, the support shaft of the tie loft end on the steering shaft side is made to have substantially the same inclination in the longitudinal direction as the steering axis of the front wheels.

e. Operation When the front wheel runs up and down on a stepped portion such as a stone and moves up and down with respect to the vehicle body, the left and right wheels move up and down in approximately the same direction as the support shaft of the tie rod end. At this time, the tie rod only moves its tip up and down following the up and down movement of the wheels, but does not act in the direction of steering the wheels.

Further, the rotation operation of the steering shaft is transmitted to both axles via the tie rod, and the knuckle arm is rotated in accordance with the width of movement of the tie rod, thereby steering both axles. At this time, since the support shaft of the tie rod and the inclination of the king pin substantially match, the king pin rotates in accordance with the rotation angle of the support shaft. In addition, when the wheel is supported by a ball joint, the inclination of the shaft connecting the ball joint is approximately the same as the support shaft of the knuckle arm, so the rotation angle corresponding to the rotation operation of the steering shaft is adjusted in both directions. It will be applied to the axle.

f. Examples Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

In FIGS. 1 and 2, ■ is a body frame of a straddle-type four-wheeled vehicle having two front wheels 2 and two rear wheels 3, respectively. 4 is a swing type engine unit, and a rear wheel axle 5 is supported at the rear end of the engine unit 4.

The front wheel 2 is supported by a double wishbone type suspension 6, which is supported by a suspension arm 7.
A wheel shaft 9 is supported via upper and lower ball joints 8 provided at the tips of the wheels.

IO is a steering shaft for steering the front wheels 2, and this steering shaft 10 is supported by the vehicle body frame 1 via a steering head 11.

This steering shaft 10 has a universal shield 12 interposed in the middle of its lower end, and the inclination X of the lower side 10a of this universal joint 12 is made to substantially match the inclination Y of the axis connecting the ball joint 8. Further, this inclination angle X is approximately the same angle as the stroke direction Z of the front wheel 2.

Reference numeral 13 denotes a steering arm attached to the lower end of the steering shirt 1-10, which commonly supports the base ends of tie rods 14+ and 14g for steering the front wheels 2 so as to be rotatable via a support shaft 15. are doing. This support shaft 15
is the X at about 1 on the lower side 10a of the steering shaft 10
and its slope X' are made to match. These tie rods 1
The tips of the wheels 4+ and 14g are pivotally supported by a knuckle arm 16 provided on the wheel shaft 9. 17 is a suspension unit that supports the suspension arm 7.

Next, the operation of the vehicle steering system will be explained.

When the front wheels 2 ride on a stepped portion while the vehicle is running, both the left and right wheels 2 stroke upward relative to the vehicle body frame 1.

At this time, the tips of the tie rods 141 and 141 move upward, but the stroke direction Z of the wheel 2 and the support shaft 15
The left and right wheels 2 move up and down in the same direction because the inclination X' is the same.

On the other hand, when the steering shaft 10 is rotated, the steering arm 13 is rotated accordingly, and the tie rods 14+ and 14 are operated.

The tie rods 14+ and 14□ are operated along the trajectory of the support shaft 15, and the knuckle arm 16 is operated in a trajectory corresponding to this, thereby steering both the left and right wheels 2.

The left and right wheels 2 are steered around an axis that connects the ball joint 8, and this axis connects the tie rod 14+ and the 14g support shaft 1.
5 and its inclination Y, the wheels 2 can be steered at an angle corresponding to the rotation angle of the steering shaft 10.

g. Effects of the Invention As described above, according to the vehicle steering system of the present invention,
In a vehicle steering system in which a knuckle arm for steering the front wheels and a steering arm supported by a steering shaft are connected via tie rods, the support shaft of the tie rod end on the steering shaft side is connected to the steering shaft of the front wheels. Since the inclination in the longitudinal direction is made almost the same as that in the front and back directions, it is possible to improve maneuverability without being affected by unevenness of the road surface.

[Brief explanation of drawings]

FIGS. 1 and 2 are conceptual diagrams showing an embodiment of a vehicle steering system according to the present invention, and FIGS. 3 and 4 are conceptual diagrams showing a conventional vehicle steering system. 1...Vehicle frame, 2...Front wheel, 6...
・Double wishbone type suspension, 8...Ball joint, 9...Wheel axle, 10...Steering shaft, 12...Universal joint, 13...Steering arm, IL, 14... ... Tie rod, 15... Support shaft, 16... Knuckle arm.

Claims (2)

[Claims] (1) In a vehicle steering system in which a knuckle arm for steering a front wheel and a steering arm supported by a steering shaft are connected via a tie rod, the support shaft of the tie rod end on the steering shaft side is connected to the front wheel. A steering system for a vehicle, characterized in that an inclination in a longitudinal direction substantially coincides with a steering axis of the vehicle. (2) The vehicle steering system according to claim (1), wherein the stroke direction of the front wheel and the longitudinal inclination of the support shaft are substantially the same.