JPS5975867A - Steering apparatus for car - Google Patents

Abstract

PURPOSE:To improve steering performance in high-speed traveling and operation performance of a steering wheel in low-speed traveling by allowing the captioned apparatus to be deflection-adjustable in the radial direction in accordance with a car-speed. CONSTITUTION:During low-speed traveling, a computer 64 receives a signal supplied from a car-speed sensor 65 and judges the speed and then controls the output revolution of a motor 61 in accordance with the car-speed at this time. A joint member 42 is deflected downward by the inclination of an arm member 51, and therefore, the output shaft 41 in a rear wheel steering system is deflection- slided in parallel to axis line and in the radial direction with respect to an input shaft 31 through a slide mechanism type joint 35 interposed. When the car- speed increases, the computer 64 allows the motor 61 to revolve reversely, and the arm 51 is tilted inversely, and when the input shaft 31 is turned, tie rods 13 and 13 are moved leftward inversely, and also rear wheels are steered in the same direction to front wheels, and the steering angle ratio between front and rear wheels is varied continuously according to the car-speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a steering system for a vehicle that steers both the front wheels and the rear wheels through the steering operation of the steered wheels. The present invention relates to a vehicle steering system that can be controlled by

The rotation necessary for steering the rear wheels is taken out from the front wheel steering system through the linkage member as rotation of the input shaft, and the rotation is applied indirectly or directly to the eccentric pin by the crank rotation of the eccentric pin provided at the rear end of the input shaft. A vehicle that steers the front and rear wheels simultaneously by outputting lateral movement to the connected and supported left and right rear wheel steering tie rods and changing the steering ratio of the front and rear wheels in proportion to the steering angle. The present applicant has previously provided a steering device (Japanese Patent Application No. 118698/1983, etc.).

According to such a steering device, it is possible to steer the rear wheels in the same direction as the front wheels by operating a small steering angle of the steered wheels, and it is also possible to steer the rear wheels in the opposite direction by operating a large steering angle, thus making it possible to drive at high speed. In addition to improving the maneuverability of the vehicle, the steering angle can be set to a dog position to obtain a small turning radius when making U-turns or manoeuvring in a parking lot, resulting in good maneuverability of the vehicle.

The present invention further improves the above-mentioned steering system so that the steering angle ratio between the front wheels and the rear wheels can be controlled according to the vehicle speed. The rear wheels are steered in the same direction as the front wheels, and when running at low speeds, the rear wheels are steered in the opposite direction to the front wheels, thereby improving maneuverability at high speeds and maneuverability of the steered wheels when running at low speeds. To provide a steering device for a vehicle that improves the performance of a vehicle.

In order to achieve such an object, the present invention connects an input shaft that rotates in conjunction with a steering wheel and an output shaft that connects and supports left and right rear wheel steering tie rods via a joint such as a slide mechanism. The steering device is constructed by incorporating a control device that can adjust the deviation in the radial direction according to the vehicle speed by, for example, sliding the output shaft up and down with respect to the input shaft while keeping the output shaft parallel to the axis.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Fig. 1 is a perspective view showing the general basic structure of a four-wheeled vehicle equipped with a steering system according to the present invention, Fig. 2 is an enlarged perspective view of the main parts, and Fig. 3 (a+, (bl, (c) ) is a schematic rear view showing the operating principle of the control device.

The tip of the handle shaft 2 of the steering wheel 1 is incorporated into a rack-and-binion type front wheel steering gear box 20, and meshes with a drive pinion at the tip of the handle shaft 2 within the gear box 20, as is known. On the left half of the rack is a driven binion (both not shown in the diagram).

) mesh with each other, and tie rods 3, 3 are connected to both ends of the rack shaft 21, which protrudes from the left and right sides of the gear box 20, respectively. A knuckle arm 4 is attached to the outer end of the tie rods 3, 3.
, 4 are connected, and the front wheels 6, 6 are connected to the knuckle arm 4.
, 4 are supported by axles 5, 5 which protrude outward.

The front wheels are steered by steering the handlebar 1. In other words, the rotation of the handlebar shaft 2 causes the rack shaft 21 to move left and right with respect to the gear box 20 through the engagement of the binion and the rack. 3,3 moves left and right,
The knuckle arm 4°4 rotates in the left and right direction to rotate the front wheels 6, 6.
is steered.

On the other hand, the rear part of the pinion shaft 22 of the driven binion that meshes with the left half of the rack of the rack shaft 21 is led out rearward from the gear box 20, and is connected to a long linkage shaft 24 via a universal joint 23. An input shaft 31 is connected to the rear end via a universal joint 25.

The driven pinion shaft 22 may be connected to the rack shaft 21 from below, or may be connected to both 21 from above.
．． The driven pinion shaft 22 is incorporated into the gear box 20 with an idle gear interposed between the driven pinion shaft 22 and, in this case, the driven pinion shaft 22 rotates in the opposite direction to the handle shaft 2.

The input shaft 31 is arranged to match the left-right center line of the vehicle, and is rotatably supported by a bearing bracket 32 fixed to the vehicle body. An output shaft 41 is connected to the rear end of this input shaft 31 via a joint 35 configured by a slide mechanism.

That is, a guide member 36 having a C-shaped channel in cross section is fixedly integrated with the input shaft 31 at right angles to the rear end thereof, and the front end of the force output shaft 41 is engaged with the C-shaped channel of the guide member 36 to extend its length. A slide member 37 that can freely slide in the direction is fixed and integrated. The guide member 36 is initially set at a neutral position for steering the rear wheels, with its length direction aligned with the vertical direction, and the output shaft 41 is disposed parallel to the axis of the input shaft 31.

In this way, the guide member 36 and the slide member 3 are connected to the input shaft 31.
The output shaft 41 is connected via a slide mechanism type joint 35 consisting of 7.

A joint member 42 is loosely fitted and supported on the output shaft 41, and the joint member 42 connects and supports left and right tie rods 13.13 from above to left and right shoulders 43.43 via ball joints 44.44, respectively. An intermediate portion of an arm member 51 whose length direction is in the left-right direction is fixed to the rear surface of this joint member 42. The right end of the arm member 51 is pivoted toward the vehicle body via a link member 52 and a link bracket 53. supported, and the left end is the first
It is also pivotally supported on the vehicle body side via a link member 54, a second link member 55, and a link bracket 56.

Then, the shaft 57 of the second link member 55, which is located above the first and second link members 54 and 55 that pivotally supports the left end of the arm member 51 and is pivotally supported in the left-right direction by the link bracket 56, A sector gear 58 is fixedly integrated with the second link member 55, and the sector gear 58 is configured to rotate together with the second link member 55.

A rear wheel 16.16 is supported on an axle 15.15 extending outwardly from knuckle arms 14, 14 connected to the outer ends of tie rods 13.13.

On the other hand, a motor 61 is disposed on the vehicle body side of the left end outer extension of the arm member 51, and an output shaft 62 of the motor 61 constitutes a worm gear 63, and the worm gear 63 and the sector gear 58 mesh with each other as shown in the figure. .

By the way, a computer 64 is disposed in the vehicle, and this computer 64 receives signals from a vehicle speed sensor 65 that detects the vehicle speed and a position sensor 66 that detects the rotational position of the second link member 55, and calculates an appropriate value according to the vehicle speed. A control signal is sent to the motor 61 to control the output rotation of the motor 61.

The operation of the above-mentioned control device will be described with reference to FIG. 3, which schematically shows the operation from the rear side.
1 and the pivot point p of the joint member 42 coincides with the axis 0 of the input shaft 31 as shown in FIG. 3(a), the input shaft 31 and the output shaft 41 are concentric. rotate,
Therefore, at this time, the joint member 42 does not swing from side to side, and the tie rods 13, 13 whose inner ends are connected to the joint member 42 remain stationary, and only the front wheels 6, 6 are steered at this time, and the rear The wheels 16.16 cannot be steered at all as in conventional vehicles.

By the way, when the vehicle is running at a low speed below the set value, the computer 64 receives a signal from the vehicle speed sensor 65 and makes a judgment.
The output rotation of the motor 61 is controlled according to the vehicle speed at that time. By controlling the rotation of this motor 61, the output shaft 62 of the motor
The worm gear 63 formed in the worm gear 63 rotates the sector gear 58 that meshes with the worm gear 63, and the second link member 55, which rotates together with the sector gear 58, swings downward about the pivot shaft 57, and as a result, the arm member 51 rotates. As shown in FIG. 3 (c), the left end is tilted downward.

Due to the inclination of the arm member 51, the joint member 42 integrated with the intermediate portion of the arm member 51 is deflected downward, and the output shaft 41 of the rear wheel steering system, which loosely supports the joint member 42, is of the slide mechanism type. The input shaft 3 due to the interposition of the joint 35
1 in the radial direction, that is, in this case, downward, and parallel to the axis.

In this way, the pivot point p of the joint member 42 is located at the input shaft 3.
If the input shaft 31 is rotated, for example, counterclockwise by an angle θ1 at this time, the tie rod 13.13 will move to the right as shown by the broken line in Fig. 3 (h9). However, the rear wheels 16, 16 are steered in the opposite direction to the front wheels 6, 6, in this case the front.

The rear wheel steering angle ratio is continuously changed according to the vehicle speed.

If the vehicle speed then increases beyond the initial setting, the computer 64 causes the motor 61 to reverse, so that the arm member 51 tilts in the opposite direction as shown in FIG. 3(C) and thus pivots. 7-T point p is also deviated upward from the axis 0, and if the input shaft 31 is rotated counterclockwise by an angle θ2 in the same manner as described above, the tie rod 13.13 becomes as shown in FIG. 3(C). As shown by the broken line, the rear wheels 16 and 1 move to the left in the opposite direction to the above.
6 is also steered in the same direction as the front wheels 6, 6, and in this case, the front and rear wheel steering angle ratios are continuously changed according to the vehicle speed.

As mentioned above, since the rear wheels are steered in the opposite direction to the front wheels when driving at low speeds, the turning radius of the vehicle can be significantly reduced, which not only improves the turning performance of the steered wheels.
It is possible to further improve the maneuverability of the vehicle when making a U-turn or manipulating people in a parking lot.

Furthermore, when driving at high speeds, the rear wheels are steered in the same direction as the front wheels, so even immediately after the start of steering, the rear wheels generate cornering force at the same time as the front wheels7, and the lateral acceleration of the vehicle reaches the intended value in a short time. It is possible to improve maneuverability by improving steering response.

In the above embodiment, the input shaft 31 and the output shaft 4 of the rear wheel steering system are
Although the input shaft 131 and the output shaft 141 are connected by a sliding joint 35, it is of course possible to connect the input shaft 131 and the output shaft 141 by any other universal joint 135 as shown in FIG.

Furthermore, the control device that can adjust the deviation of the output shaft 41 in the radial direction with respect to the input shaft 31 is not limited to the embodiment, and can be used, for example, by directly connecting an arm member or the like to the output shaft 41. It is also possible to connect a control device, and the tie rods 13, 13 may be directly and commonly connected and supported to the output shaft 41 without using the joint member 42.

As is clear from the above description, according to the present invention, the output shaft of the rear wheel steering system that directly or indirectly connects and supports the left and right rear wheel steering tie rods is connected to the input shaft that rotates in conjunction with the steered wheels. A control device is installed that connects the output shaft to the input shaft through a joint such as a slide mechanism, and also slides the output shaft up and down while keeping the axis parallel to the input shaft, thereby making it possible to adjust the deviation in the radial direction according to the vehicle speed. Since the steering system has been incorporated, the steering angle ratio between the front wheels and the rear wheels can be controlled according to the vehicle speed as expected.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a perspective view showing the general basic structure of a four-wheeled vehicle equipped with a steering system according to the present invention, and FIG. 2 is an enlarged perspective view of the main parts thereof. , Figure 3 (a
), (C), and (C) are schematic rear views showing the operating principle of the control device, and FIG. 4 is a partial perspective view showing a modification of the joint. In the drawing, 1 is a steering wheel, 6 is a front wheel, 13 is a tie rod for rear wheel steering, 16 is a rear wheel, 31, 131 is an input shaft, 35.1
35 is a joint, 41, 141 is an output shaft, 51° 52...
66 is a control device. Patent applicant Honda Motor Co., Ltd. Agent Patent attorney 2 1) Production department Patent attorney Kuni Ohashi Production volume Patent attorney 2
Yama Yu Figure 3

Claims (2)

[Claims] (1) In a vehicle steering system in which the rear wheels are steered along with the front wheels by the steering operation of the steered wheels, an input shaft that rotates in conjunction with the steered wheels is connected to a tie rod for steering the left and right rear wheels. A steering system for a vehicle, which is connected to a supported output shaft via a joint, and includes a control device that can adjust the deviation of the output shaft relative to the input shaft in the radial direction according to vehicle speed. (2) The vehicle steering device according to claim 1, wherein the joint is a slide mechanism that allows the output shaft to be slid in the radial direction with respect to the input shaft, and is slidable while keeping the output shaft parallel to the axis.