JP2621199B2 - Vehicle steering system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering apparatus for a vehicle, and particularly to a steering apparatus for holding a steering angle of a steering wheel at substantially zero when a slider is located on a center line of a fixed fan gear. When the slider is deviated from the center line of the fan-shaped fixed gear by rotating the steering wheel, the steered wheels are turned in the opposite phase to the main steered wheels, and the steering angle of the steered wheels is changed nonlinearly. Accordingly, the present invention relates to a vehicle steering device that can improve steering stability, improve small turning performance, and can simplify the configuration.

[Related Art] In a vehicle, a front wheel is usually provided so as to be steerable in a desired traveling direction of the vehicle, and a rear wheel is provided in equilibrium with the front-rear direction of the vehicle. When the front wheel of a vehicle that steers such two front wheels is steered and turned, the front wheel and the rear wheel do not match the turning circle, and the rear wheel enters the turning circle due to the inner wheel difference at low vehicle speed. The vehicle turns with the attitude, and at high vehicle speed, the vehicle turns with the front wheel entering the inside of the turning circle due to centrifugal force. For this reason, even if the front wheels are steered in the turning direction, which is the traveling direction of the vehicle, there is a problem in that the vehicle cannot be steered by matching the attitude of the vehicle with the turning direction.

Therefore, a vehicle having a four-wheel steering device that improves traveling performance by steering not only the front wheels but also the rear wheels has been proposed.

Such a vehicle steering system is disclosed in, for example,
-97565. The large steering angle in which the rear wheel is steered in the direction opposite to the front wheel than the maximum steering angle of the rear wheel during a small steering angle operation in which the rear wheel is steered in the same direction as the front wheel is described in this publication. The maximum steering angle of the rear wheel at the time of operation is increased to improve the maneuverability during high-speed traveling, and the inner wheel difference and turning radius during low-speed traveling are reduced.

[Problems to be solved by the invention]

By the way, in the conventional steering device, since the steering angle of the front wheel is proportionally increased as the steering angle of the front wheel is increased by turning the steering wheel greatly, there is a disadvantage that steering stability and small turning performance are reduced. there were. In addition, the configuration of the steering device is complicated, and the functions of the respective members cannot be sufficiently exhibited, resulting in a disadvantage of low reliability.

[Object of the invention]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention holds the steering angle of the steered wheels substantially at zero when the slider is positioned on the center line of the sector-shaped fixed gear, and rotates the handle to rotate the steering wheel in the sector-shaped manner. If the fixed wheel deviates from the center line, the steerable wheels are steered in the opposite phase to the main steerable wheels, and the steering angle of the steerable wheels is changed non-linearly, thereby improving steering stability and turning It is another object of the present invention to provide a vehicle steering device that improves the reliability and simplifies the configuration, makes full use of the functions of each member, and improves reliability.

[Means for solving the problem]

In order to achieve this object, the present invention relates to a main steering wheel which is steered by a main steering unit so as to steer a vehicle in a desired traveling direction, and a steering operation performed by a secondary steering unit in accordance with a steering state of the main steering wheel. A steering arm connected to the main steering means, a sector fixed gear for swingably supporting the oscillation arm, and meshing with the sector fixed gear. A planetary gear that is pivotally attached to the swing arm, a moving arm that is fixed to the planetary gear, and is slidably mounted on the movable arm and slides in a slide groove formed in a slider guide of the swing arm. And a supporting arm provided in parallel with the swing arm, and the steering wheel of the driven wheel is steered when the slider is located on the center line of the sector fixed gear. Angle is almost zero When the slider is deviated from the center line of the fan-shaped fixed gear by rotating the steering wheel while holding the steering wheel, the slave wheel is steered in the opposite phase to the main steering wheel, and the steering of the slave wheel is controlled. A steering control means for changing the angle nonlinearly is provided.

[Action]

According to the configuration of the present invention, when the slider is located on the center line of the sector-shaped fixed gear, the steering angle of the driven wheel is maintained at substantially zero, and the driven wheel is maintained in a substantially straight traveling state, Stability can be improved. When the slider is deviated from the center line of the fan-shaped fixed gear by rotating the steering wheel, each member moves smoothly, and the steered wheels are controlled in a phase opposite to that of the main steered wheels and nonlinearly in steering angle control. Therefore, the minimum turning radius of the vehicle can be reduced to improve the small turning performance.

〔Example〕

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

1 to 5 show an embodiment of the present invention.
In the figure, 2 is a vehicle, 4 and 4 are front wheels as main steering wheels, and 6.6 are rear wheels as slave wheels. The front wheels 4.4 are connected to the main steering means 10 via front wheel tie rods 8.8. The main steering means 10 is operated by rotating a steering wheel (not shown) to steer the front wheels 4 via tie rods 8.8 for the front wheels, and
In a desired traveling direction.

The rear wheels 8.8 are steered by a steering control means 14 which is a secondary steering means connected via a steering transmission 12 having one end connected to the primary steering means 10. The steering control means 14 is connected to the rear wheels 6 via the rear wheel tie rods 16.
6.

The steering control means 14 is configured such that the slider 38
Is located on the center line P of the rear wheel 6, the steering angle of the rear wheels 6, 6 is maintained at substantially zero, or is maintained in the same phase as the front wheels 4, 4, and the slider 38 is operated by rotating the steering wheel so that the slider 38 If it is out of the center line P of the sector fixed gear 24, the rear wheel 6
6 is turned in the opposite phase to the front wheels 4 and 4 and the rear wheels 6
The steering angle of No. 6 is changed nonlinearly, and is configured as follows.

That is, as shown in FIGS. 2 and 3, the steering control means 14 includes a swing arm 20 which pivotally connects the other end side of the steering transmission body 12 which is the main steering means 10 to the first pivotally supporting portion 18. A fan-shaped fixed gear 24 for swingably supporting the swing arm 20 by a second pivotally-supported support portion 22; and a third pivotally supported meshing engagement with the fan-shaped fixed gear 24 at the distal end of the swing arm 20. A planetary gear 28 pivotally connected by a part 26 and a moving arm 30 having one end fixed to the planetary gear 28
The other end of the moving arm 30 is pivotally connected at one end by a fourth pivoting support portion 32 and slidably provided in a slider groove 36 formed in a slide guide portion 34 of the swing arm 20. A connecting rod 42 pivotally connected to the slider 38 at the other end by a fifth pivoting support portion 40.

A supporting arm 44 is provided on the second pivotally supporting portion 22 and the third pivotally supporting portion 26 in parallel with the swing arm 20.

Further, the second pivoting support portion 22 has a function of an output pivot, and tie rods 16 for rear wheels connected to the rear wheels 6.6 are connected to the second pivoting support portion 22, for example. .

The fan-shaped fixed gear 24 is fixedly supported by fixtures 46.

 Next, the operation of this embodiment will be described.

When the steering wheel is operated to rotate, the main steering means 10 operates to operate the steering transmission body 12, for example, the steering transmission body 12 is pushed as shown in FIG. As a result, the first pivot support portion 18
Moves from position A to position B. Therefore, the slider 38
Is located off the center line P of the fan-shaped fixed gear 24.

With the movement of the first pivotally supporting portion 18, the swing arm 20 is moved.
And the support arm 44 rotates clockwise about the second pivot support 22, so that the planetary gear 28 moves while rotating along the sector fixed gear 24.

The rotation of the planetary gear 28 causes the moving arm 30 to rotate clockwise and the slider 38 via the connecting rod 42.
Is pushed. The amount of movement of the slider 38 is controlled by the movement of the output pivot,
, The rear wheels 6 are steered. That is, the steering control means
14 changes the steering angle of the rear wheels 6.6 non-linearly with respect to the steering angle of the front wheels 4.4, and can change the rear wheels 6.6 as shown by the solid line N in FIG. Further, the position of the output pivot is set at the center of the fan-shaped fixed gear 24, that is, the second pivotally supporting portion 22.
(See the broken line in FIG. 5)
bo), and the steering direction of the rear wheels 6, 6 can be controlled by changing the output direction and the output amount as shown by the broken line M in FIG.

As a result, when the slider 38 is located on the center line P of the sector fixed gear 24, that is, when the steering angle of the front wheels 4, 4 is small, the steering angle of the rear wheels 6, 6 is maintained at substantially zero. Or the front wheels are controlled to be in phase with each other.
6 can be maintained in a substantially straight-ahead state, and the steering stability can be improved. Also, rotate the handle to move the slider 38
Deviates from the center line P of the sector fixed gear 24, that is,
When the steering angle of the front wheels 4, 4 is large, the steering angle of the rear wheels 6, 6 is steered in a phase opposite to that of the front wheels 4, 4, and is changed non-linearly to improve the small turning performance of the vehicle 2. Can be done.

Further, according to this embodiment, the configuration is simple, the functions of the respective members can be sufficiently exhibited, and the reliability can be increased.

〔The invention's effect〕

As is apparent from the above detailed description, according to the present invention, the swing arm connected to the main steering means, the sector fixed gear for swingably supporting the swing arm, and the sector fixed gear meshing with the sector fixed gear and swinging. A planetary gear pivotally attached to the moving arm; a moving arm fixed to the planetary gear; and a slider pivotally attached to the moving arm and slidably provided in a sliding groove formed in a slider guide portion of the swing arm. A connecting rod, and a supporting arm provided in parallel with the swing arm, and when the slider is positioned on the center line of the sector-shaped fixed gear, the steering angle of the steered wheels is maintained at substantially zero, and the handle is moved. Steering control means is provided for turning the steered wheels in a phase opposite to that of the main steered wheels and for changing the steering angle of the steered wheels non-linearly when the slider is deviated from the center line of the sector fixed gear due to the rotation operation. By Improves the steering stability, improve maneuverability properties, also aims to simplify the structure,
The function of each member can be fully exhibited, and the reliability can be improved.

[Brief description of the drawings]

1 to 5 show an embodiment of the present invention, FIG. 1 is a schematic plan view of a vehicle provided with steering control means, FIG. 2 is a front view of the steering control means, and FIG. 3 is a side view of the steering control means. FIG. 4 is an explanatory diagram showing an operation state of the steering control means, and FIG. 5 is a characteristic diagram showing a relationship between an input (x) and an output (y) of the steering control means. In the figure, 2 is a vehicle, 4 and 4 are front wheels, 6 and 6 are rear wheels, 10 is main steering means, 12 is a steering transmission body, 14 is steering control means, 16 and 16 are tie rods for rear wheels, 20 Is the swing arm, 24
Is a fan-shaped fixed gear, 28 is a planetary gear, 30 is a moving arm, 38 is a slider, and 42 is a connecting rod.

Claims (1)

(57) [Claims] 1. A main steering wheel steered by a main steering means to steer a vehicle in a desired traveling direction, and a slave steering wheel steered by a slave steering means according to a steering state of the main steering wheel. A swing arm connected to the main steering means, a sector fixed gear that swingably supports the swing arm, and the swing arm that meshes with the sector fixed gear and engages with the swing arm. A planetary gear that is pivotally mounted on the planetary gear; a moving arm that is fixed to the planetary gear; and a slider that is pivotally mounted on the moving arm and slidably provided in a slide groove formed in a slider guide portion of the swing arm. And a supporting arm provided in parallel with the swing arm, and when the slider is positioned on the center line of the sector fixed gear, the steering angle of the driven wheel is maintained at substantially zero. Along with Han When the slider is deviated from the center line of the fan-shaped fixed gear by rotating the steering wheel, the driven wheel is steered in a phase opposite to that of the main wheel, and the steering angle of the driven wheel is nonlinearly changed. A steering apparatus for a vehicle, comprising a steering control means for changing the steering control.