JPH02254060A - Alarming device for vehicle having rear wheel steering device - Google Patents

Abstract

PURPOSE:To improve running safety by a method wherein, in a rear wheel steering device having an opposite phase steering mechanism, when rear wheels and front wheels are steered in an opposite phase, an alarm indicating that the rear part of the car body of a self-car is turned and protruded outwardly is reported to a subsequent vehicle. CONSTITUTION:During steering of front wheels, the steering characteristics of rear wheels are changed at a predetermined car speed of, for example, 40km/h forming a boundary between a change and an unchanged state. On the side where a car speed is higher than the above car speed, rear wheels are steered in an iso-phase with front wheels to improve high speed stability, and on the side where it is lower than the above car speed, the rear wheels are steered in an opposite phase to the front wheels to improve short radius turning properties. In a vehicle 1 having the rear wheel steering device, left and right winker lamps 8l and 8r to report the turning direction of a self-car to a subsequent car when the vehicle 1 is turned for starting are mounted to a rear end plate 6 of the lower part of the rear end of the car body. A message plate 9 to alarm it to a subsequent car that a rear is protruded during the initial stage of a turn is mounted in approximately in a central position in the direction of the width of a car, and English letters of, for example, REAR are displayed by flickering.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a warning device for a vehicle behind a vehicle equipped with a rear wheel steering system having anti-phase steering gear grooves.

[Prior Art] Conventionally, rear wheel steering devices for vehicles such as automobiles have been designed to steer the rear wheels in a direction opposite to the steering direction of the front wheels.
Those equipped with a so-called anti-phase steering mechanism are generally well known (see, for example, Japanese Patent Laid-Open No. 63-97468).
. A four-wheel steering system 1j (d W
For S cars), the steering angle of the front wheels is usually greater than a predetermined value (in the case of a steering angle response type), or the range where the vehicle running speed is lower than a predetermined value (in the case of a quick response type), etc. The steering characteristics of the rear wheels are set so that the rear wheels are steered in the opposite phase to the front wheels.For example, when turning the vehicle with a small turning radius, such as when maneuvering the vehicle in a parking lot. (In other words, when turning the steering wheel significantly at low vehicle speeds), it is possible to significantly improve the vehicle's ability to turn around easily.

However, in a 4WS vehicle equipped with the rear wheel reverse phase steering mechanism, as shown in FIG.
2. By steering l02r to the opposite phase to the front wheels 101c and l01r, the turning radius of the entire vehicle can be changed from R2 to It4 compared to a normal 2WS vehicle (see the broken line in Figure 7). Although it can be made smaller, at the beginning of a turn, the rear of the vehicle protrudes more outward than in the case of a 2WS vehicle, a so-called rear overhang.

That is, in the case of a 2WS ton held in the steering direction of the rear wheel 102 (', l 02r' or in the straight forward direction (longitudinal axis direction) of the vehicle +00), the outer edge portion 103Q of the rear end of the vehicle,
As shown by the broken line arrow in FIG. 7, the rear wheel! 0212
Since it turns while drawing a movement trajectory approximately along the steering direction of
The outer edge portion 103Q of the rear end of the vehicle is, as shown by the solid arrow in FIG. It turns while drawing a locus of movement approximately along the steering direction of the wheels 102C. As a result, the outer edge portion 103C of the rear end of the vehicle, at the initial stage of the vehicle turning, protrudes more outward than the outer surface of the vehicle when the vehicle is traveling straight ahead.

For this reason, for example, a 4WS vehicle once stopped at an intersection
When the dWS vehicle 100 is turning to the right in FIG.
Pass on the left side of O (if you try to pass J, this following vehicle 1
In order to avoid contact with the vehicle ahead 100, the vehicle 10 needs to take an extra course to the left by the amount of rear projection of the vehicle ahead 100 at the beginning of the turn.

[Problems to be Solved by the Invention] However, in the past, although the following vehicle 110 can know the turning and turning direction of the preceding vehicle 100 by blinking blinker lamps, etc., the following vehicle 110 cannot easily predict the rear overhang at the beginning of the turn. Therefore, when passing by the side of the vehicle ahead 100, it is conceivable that contact with the outer edge portion 103e of the rear end of the vehicle ahead may not be avoided.

This invention has been made in view of the problem ``-2'', and is intended to provide a vehicle warning to notify the rear vehicle of the rear overhang at the initial stage of a turn in a vehicle equipped with rear wheel reverse phase steering (rear side). The purpose is to provide equipment.

[Means for Solving the Problems] Therefore, the present invention provides a vehicle equipped with a rear wheel steering device having an anti-phase steering device (1 When turning, a warning means was installed to warn the vehicles behind that the rear of the own vehicle's body would protrude outwards from the turn.

[Effects of the Invention] According to the present invention, when the rear wheels are steered in a phase opposite to that of the front wheels and the vehicle is turned, the above-mentioned warning means warns the vehicle behind.
Since it is possible to warn in advance about the rear overhang of one's own vehicle at the beginning of a turn and call attention to it, it is possible to effectively prevent collisions when rear vehicles pass by the side of one's own troops.

Embodiments] Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

FIG. 3 is a plan view schematically showing the overall structure of the steering mechanism of the vehicle (truck) according to the present embodiment. As shown in this figure, in the automobile 1, the left and right front wheels 2L2r are steered. The front wheel steering device 10 includes a steering shaft I2 rotatably supported with respect to the vehicle body, a steering wheel II fixed to the rear end of the steering shaft 12 and rotatably operated, and a steering wheel II that reciprocates in a narrow width direction. It is possible to extend the tie [l soto 5Q, 5r and knuckle arm 1 (
A front wheel steering rod 15 is connected to the left and right front wheels 2Q and 2r via i and ir, and the front wheel steering rod 15 has a pinion 13 fixed to the curved end of the steering wheel 12. A rack 16 is provided which meshes with the rack.

Then, steer the steering wheel 11 (rotation operation)
Then, the pinion 13 is rotated via the steering shaft 12, and the rotation of the pinion 13 moves the 1111-wheel steering rod 15 in the vehicle width direction via the track rack 16, and this movement causes the tie rod to move. 5
The left and right 1r wheels 2 (7, 2r) can be steered via L5r and knuckle arm 412.4r.

Although not specifically shown, the steering force of the steering wheel I+ is power assisted by, for example, an i+b pressure type power steering mechanism.

Further, the rear wheel steering device 60 that steers the left and right rear wheels 52L52r is operated by a servo motor 62, as will be explained in detail later.
The rear wheel steering device 60 is equipped with a so-called motor-type reverse phase steering mechanism that steers the rear wheels in a phase opposite to that of the front wheels through drive control of the rear wheel steering device 60.
(!, 55r is moved in the vehicle width direction, and the knuckle arms 54d, 55r are connected to the tie rods 5!M, 55r.
4r, the left and right rear wheels 52L52r are steered.

The rear wheel steering device 60 will be described below.

In the rear wheel steering device 60 according to this embodiment, the left and right rear wheels 52
A speed reduction device 65 connected to an output shaft 62a of a servo motor 62 is connected to a rear wheel steering rod 61 that steers the L52r. The rod 61 is moved in the vehicle width direction, and the rear wheels 5212, 52r are steered.

An electromagnetic brake 63 is provided on the output shaft 62a of the servo motor 62, and when the brake is operated, the motor output shaft 62a and the rear wheel steering rod 6I are locked, and the rear wheel 52 is locked.
The steering state of C, 52r is maintained. Further, an electromagnetic clutch 64 is interposed between the motor output shaft 62a and the speed reduction device 65, and a position return device 66 is provided on the rear wheel steering rod 61 to return the steering rod 61 to the neutral position. If an abnormality occurs in rear wheel steering, the electromagnetic clutch 64 is released to disengage the servo motor 62 and the rear wheel steering rod 61, and the position return device 66 The rear wheel steering rod 61 is returned to the neutral position, and the rear wheel steering rod 61 is returned to the neutral position.
ρ and 52r are prevented from returning to the neutral position where the steering angle is zero.

The vehicle 1 is configured with, for example, a microcomputer as its main part, and basically connects the rear wheels 52L to 52L via the servo motor 62, electromagnetic brake 63, and electromagnetic clutch 64.
A controller 70 for controlling the steering angle of the steering shaft 12 is provided, and the controller 70 includes a steering angle sensor 71 for detecting the steering angle of the steering shaft 12.
, the front wheel 212.2 depending on the amount of movement of the front wheel steering rod I5.
The vehicle speed sensor 73.74 on the front wheel steering angle sensor 72.2 side detects the steering fr+ of r, the rotation angle sensor 75 detects the rotation angle of the servo motor 62, and the rear wheel 52 ( Output signals from various sensors such as a rear wheel steering angle sensor 76 that detects the steering angle of the wheels 2 and 52r are manually input.

The two-legged controller 70 includes a Nicotral clutch switch 81 that detects the neutral position of the manual transmission and when the clutch pedal is depressed, an inhibitor switch 82 that detects the neutral position or parking position of the automatic transmission, and a brake pedal Various switches such as a brake switch 83 that detects when the pedal is pressed and an engine switch 84 that detects when the engine is running are electrically connected so that basic data regarding the operating state of the vehicle 1 can be manually input. It has become.

Furthermore, as shown in FIG. 1, in this embodiment, the vehicle 1
0 Rack) on the rear end plate 6 at the bottom of the rear end of the vehicle.
Left and right blinker lamps 8Q, 8 are provided on the left and right outer sides of the brake lamps 7Q, 7r, respectively, and inform the following vehicle of the direction in which the vehicle is turning when the vehicle l starts turning on the road.
r, and a message plate 9 which is provided approximately at the center in the vehicle width direction and is used to warn following vehicles of the rear overhang at the beginning of a turn. As shown in detail in FIG. 2, the message plate 9 indicates that there is a rear overhang at the beginning of a turn, for example, by flashing the English letters REAR, and indicates the direction of the rear overhang by flashing left and right arrows. For example, when the vehicle 1 starts turning to the right, the turning direction of the vehicle 1 is displayed by blinking the blinker lamp 8r on the right side, and the blinking of the English letters REAR & on the left side of the message plate 9. Due to this, the vehicle at the beginning of the turn! The display now shows that the rear section of the car is jutting out to the left.

The message plate 9 has a message display circuit 79 for blinking the English letters REΔR and left and right arrows.
(see FIG. 3) are electrically connected, the display circuit 79 is connected to the controller 70, and the controller 7
It is activated by an output signal from 0. Further, the controller 70 also controls the blinker switch 78 that blinks the blinker lamps 8f2 and 8r.
is connected to the 0N-OF of the blinker switch 78.
The F state is input as a signal to the controller 70.

The controller 70 has information about the ratio of the rear wheel steering angle to the front wheel steering angle (steering ratio) and the rear wheel steering angle to the steering amount of the steering wheel II (steering wheel rotation angle) at each vehicle speed, for example, as shown in FIG. And predetermined steering characteristics as shown in FIG. 5 are stored in advance, and the front wheels! , 2r
When the rear wheels 52L52r are steered, the rear wheels 52L52r are steered according to these steering characteristics. That is, in the case of this embodiment, the steering characteristics of the rear wheels 5212, 52r change at a predetermined vehicle speed (for example, 40 km/h), and at higher speeds than this vehicle speed, the steering characteristics of the rear wheels 5212, 52r change.
is steered in the same phase as the front wheels 2Q and 2r, but is set to be steered in the opposite phase when the vehicle speed is lower than the above vehicle speed. In addition, the steering ratio increases as the speed increases on the same phase side to improve high-speed stability, while on the opposite phase side it increases as the speed decreases to improve turning ability. .

Furthermore, in this embodiment, when the vehicle l turns by steering the rear wheels 52Q and 52r in the opposite phase to the front wheels 2f2 and 2r,
The message display circuit 79 is activated, and the English letters REAR and the arrow on the message plate 9 flash.
It is now possible to warn vehicles behind you about the rear overhang of your own troops at the beginning of a turn.

The operation of the message display circuit 79 will be explained below with reference to the flowchart shown in FIG.

When the operation of the rear wheel steering device 60 starts, first, in step #1, input signals from each sensor and switch are read. Next, in step #2, the vehicle speed V is set to 20 kph based on the input signals from the vehicle speed sensors 73 and 74.
It is determined whether or not the speed is less than m/h, and if YES, it is determined in step #3 whether or not the turn signal switch 78 is turned on. If the result of this judgment is YES, the message display circuit 79 is turned ON in step #4, the English letters REAR on the message plate 9 are made to blink, and the blinking blinker lamp 8 or 8 is blinked.
An arrow in the opposite direction to r can be avoided by blinking.

On the other hand, if the determination result is NO in at least either step #2 or step #3,
Returning to step #l, the same cycle is repeated thereafter.

As explained above, according to this embodiment, the vehicle speed ■ is 2
When the blinker switch 78 is turned on at speeds below 0 km/h, that is, when the vehicle is turned in the opposite phase region, the blinking of the English letters REAR and the arrow on the mesosage plate 9 will cause the rear vehicle to Since it is possible to warn the driver of the rear overhang at the beginning of the turn of the steering wheel and to urge the vehicle to stop, it is possible to effectively prevent the rear vehicle from coming into contact with the vehicle from the side when it passes by, thereby improving safety.

In this embodiment, the vehicle speed range in which the message display circuit 79 is activated is set to 20 km/h or less, because when the reverse phase steering mechanism is used to make a small turn of the vehicle, the vehicle speed is normally at least within the above range. Turning is performed by lowering V, and the rear bulge occurs only at the beginning of a turn when the vehicle speed V does not exceed the above range.When traveling at a vehicle speed exceeding this range, the specified rear wheel rotation This is to ensure that the rudder characteristics are obtained.

Further, in the above embodiment, a dedicated message plate 9 is provided as a warning means for warning the rear vehicle of the rear overhang, but the general public does not have enough space to provide such a message plate. For example, in the case of a passenger car, for example, only the outer parts of the left and right brake lamps can be activated to flash, and by flashing the outer parts of the brake lamps on the outside of the turn, it is possible to make the rear overhang of your own troops visible to the vehicles behind. It can warn you of the direction. In this case, the inner portions of the brake lamps on both the left and right sides light up when the brakes are applied, and when the brakes are released, only the outer portions of the brake lamps on the outside of the turn continue to flash.

In each of the above embodiments, a warning is given to the vehicle behind by visual means, but the warning may be given by a buzzer or voice.

[Brief explanation of drawings]

FIG. 1 is an overall perspective view of a vehicle according to an embodiment of the present invention, and FIG.
The figure is a front view of the message plate and turn signal lamp of the vehicle, FIG. 3 is a plan view schematically showing the overall configuration of the steering mechanism of the vehicle, and FIG. 4 is a rear view of the rear wheel steering system of the vehicle relative to vehicle speed. FIG. 5 is a graph showing the wheel steering ratio characteristics, FIG. 5 is a graph showing the rear wheel steering characteristics with respect to the steering wheel rotation angle of the rear wheel steering device, FIG. 6 is a flow chart for explaining the operation of the message display circuit, and FIG. FIG. 2 is an explanatory plan view showing turning characteristics of a conventional automobile. l...Vehicle, 2i! , 2r...front wheel, 9...message plate, 521! , 52r...rear wheel, 6o...
・Rear wheel steering device, 79...Message display circuit.

Claims (1)

[Claims] (1) In a vehicle equipped with a rear wheel steering device having an anti-phase steering mechanism, when turning the rear wheels in an opposite phase to the front wheels, the rear of the vehicle body is A rear wheel steering device for a vehicle, characterized in that a rear wheel steering device for a vehicle is provided with a warning means for warning that the rear wheel will be extended toward the outside of a turn.