JPH04232139A - Vehicle-to-vehicle distance detecting and alarming device - Google Patents

Abstract

PURPOSE:To provide a vehicle-to-vehicle distance detecting and alarming device which can tell a preceding vehicle driver that a vehicle-to-vehicle distance is shorter than a preset value. CONSTITUTION:In case that a vehicle-to-preceding vehicle distance is found in accordance with a time from the emission of laser light up to the reflection of the laser light on a preceding vehicle and the return, if the vehicle-to-vehicle distance is below a preset value, a switch 14a in a control unit 14 is closed to perform passing of head lamps 47, 48 and sound of an electric horn 42 so that such a status can be notified to a preceding vehicle driver.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an inter-vehicle distance detection/warning device, and relates to a system that detects the inter-vehicle distance between one's own vehicle and the vehicle in front, and issues an alarm when the distance becomes smaller than the safe inter-vehicle distance. It is applicable and useful.

0002

[Prior Art] The main causes of rear-end collisions caused by trucks are:
The majority of cases are caused by drivers falling asleep at the wheel or driving distracted. Due to these circumstances, a following distance detection/warning device has been developed that detects the distance between the own vehicle and the vehicle in front and issues a warning to the driver when the distance becomes less than a certain distance. ing. The current outline of this device is to emit a laser beam in front of the vehicle, receive the laser beam that hits the reflector on the rear of the vehicle in front, and calculate the inter-vehicle distance from the time taken. When the inter-vehicle distance becomes less than a predetermined distance, a buzzer inside the vehicle is set to sound.

0003

[Problem to be Solved by the Invention] In the above-mentioned inter-vehicle distance detection/warning device, although it is possible to alert the driver of the own vehicle by sounding the buzzer, the driver of the own vehicle may not notice the warning. There isn't. Therefore, if the inter-vehicle distance becomes smaller than a predetermined value, it is desirable to notify the driver of the vehicle in front of this situation as well.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, it is an object of the present invention to provide an inter-vehicle distance detection/warning device that can notify the driver of the vehicle in front that the inter-vehicle distance has become smaller than a predetermined value.

[0005]

[Means for Solving the Problems] The configuration of the present invention that achieves the above object detects the time it takes for a laser beam emitted from the own vehicle to be reflected by the vehicle in front and returns, and calculates the inter-vehicle distance. In an inter-vehicle distance detection/warning device that issues an alarm when the inter-vehicle distance becomes smaller than a safe inter-vehicle distance determined based on the braking distance and free running distance of the own vehicle, If this occurs, the headlights are controlled to flash, or the electric horn is controlled to sound.

[0006]

According to the present invention having the above structure, when the inter-vehicle distance becomes smaller than a predetermined value, the headlights flash or the electric horn sounds to notify the driver of the vehicle in front of the current situation.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of an embodiment of an inter-vehicle distance detection/warning device according to the present invention, and FIG. 2 shows an outline of its installation position.

Reference numeral 1 denotes a laser radar unit, which includes a light emitting section 2 and a light receiving section 3. The configuration of the laser radar unit 1 is shown in FIG.

The light emitting section 2 includes a laser diode drive circuit 4
, a laser diode 5, and a light emitting lens 6, and is configured to emit pulsed laser light at regular intervals. The light receiving section 3 includes a light receiving lens 7 that receives laser light reflected by a reflector of the front vehicle, a photodiode 8, an amplifier 9, a signal processor 10, and the like. Based on the time difference Δt between the light emitted by the light emitting unit 2 and the light received by the light receiving unit 3, the distance detection circuit 11 determines the inter-vehicle distance D (=
Δt/2×speed of light) is calculated.

An inter-vehicle distance signal, which is a detected value of the laser radar unit 1, is input to a control unit 14 built into the lower side of a seat 13 of a truck 12.

The laser radar unit 1 is assembled into the bumper 15 of the truck 12 as shown in FIG.
In this embodiment, three light emitting units 2 and three light receiving units 3 are provided,
As shown in Figure 4, three laser beams 16 are placed on the left, center, and right.
a, 16b, and 16c.

Reference numeral 17 denotes a vehicle speed sensor, which detects the vehicle speed from a rotating part of the transmission, etc. A detection signal from the vehicle speed sensor 17 is input to the control unit 14.

Reference numeral 18 denotes a disk 19 provided on the steering column and a light emitting/light receiving section 20 for detecting the slit thereof.
A steering angle signal, which is a detection signal thereof, is input to the control unit 14.

Details of the steering sensor 18 are shown in FIGS. 5 and 6.

The disk 19 is provided with slits 31 for angle detection at regular intervals, and on the inside thereof, one slit 32 for neutral position detection is provided offset from the center between the slits 31. . The light emitting part/light receiving part 20 has two parts for detecting the slit 31 (20
a, 20b), one for slit 32 detection (20
c) Provided. Since the positional relationship of the slits 31 on both sides of the slit 32 is different, it is detected whether the rotation is clockwise or counterclockwise with respect to the neutral position.

Regarding the detection of the neutral position, when the slit 32 is detected when the vehicle speed is 40 km/h or more, it is determined that the neutral position, that is, the steering angle is 0°. Then, based on this position, detection is performed clockwise or counterclockwise several times depending on the detection amount of the slit 31.

A wiper switch 23 functions as an example of an environmental sensor, and its ON/OFF signals are input to the control unit 14. In other words, it is determined that it is raining when the wiper switch 23 is turned on.

Other environmental sensors 24 include a raindrop sensor, a road surface sensor (G sensor), a temperature sensor, and a slip sensor. A rain sensor detects that it is raining, i.e. the road is wet, a road sensor detects whether the road is muddy or otherwise, and a temperature sensor detects whether the road is muddy or wet. In combination with detection results from other sensors, the weather and road conditions, such as icy conditions, are detected. The slip sensor detects whether the road surface is prone to slipping, that is, whether the road is a low-μ road or a high-μ road, based on the rotational speed difference between the front wheels and the rear wheels. The detection results are input to the control unit 14.

Reference numeral 21 denotes a display unit built into the instrument panel in front of the driver's seat, and is equipped with a display unit for the distance between vehicles, a buzzer for issuing a warning, and a lamp that flashes when an alarm occurs to call the driver's attention. It is also designed to issue an alarm.

In this embodiment, when the distance between vehicles becomes smaller than a predetermined value, the headlights flash and the electric horn sounds. The configuration of this part will be explained in detail based on FIG.

As shown in FIG. 7, the horn relay 40 is energized by closing the horn switch 41, closing the contact 40a and supplying current from the battery 43 to the electric horn 42. Passing relays 44 and 45 are energized by closing of passing switch 46, and contact 4
4a, 45a are closed and the headlamps 47, 48 on both sides are closed.
A current is supplied from the battery 43 to. Passing relays 44, 45 have respective contacts 44a, 45
The headlamps 47 and 48 perform an intermittent operation in which they alternately open and close, thereby causing the headlamps 47 and 48 to perform a passing operation.

The above-mentioned functions are equipped in conventional vehicles, but in this embodiment, the horn relay 40 and passing relays 44, 45 are also energized by closing the switch 14a of the control unit 14. Moreover, this switch 14a is closed when the inter-vehicle distance detected based on the inter-vehicle distance signal detected by the laser radar unit 1 is less than a predetermined value.

Therefore, according to the above embodiment, when the inter-vehicle distance becomes less than a predetermined value, the horn relay 40 and the passing relay 44 are activated by closing the switch 14a.
45 is energized, blowing the electric horn 42 and flashing the headlamps 47 and 48.

In the above embodiment, when the inter-vehicle distance becomes less than a predetermined value, either the horn relay 40 or the passing relays 44 and 45 may be energized.

[0025]

[Effects of the Invention] As specifically explained above in conjunction with the embodiments, according to the present invention, when the distance between the vehicle and the vehicle in front becomes less than a predetermined value, the sounding of the electric horn and flashing of the headlights are stopped. Since at least one of these is performed, the driver of the vehicle in front can be informed of the situation at that time, and the driver can take necessary measures.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the overall configuration of a device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a schematic positional relationship of each component.

FIG. 3 is an explanatory diagram of a laser radar unit.

FIG. 4 is a plan view of a laser beam transmission state.

FIG. 5 is a perspective view of a steering sensor.

FIG. 6 is an explanatory diagram of steering angle detection.

FIG. 7 is a circuit diagram showing an embodiment of the present invention.

[Explanation of symbols]

1 Laser radar unit 14 Control unit 14a Switch 40 Horn relay 42 Electric horn 44, 45 Passing relay 47,48 Headlamp

Claims (2)

[Claims] [Claim 1] Determine the inter-vehicle distance by detecting the time it takes for a laser beam emitted from the own vehicle to be reflected by the vehicle in front and return;
In an inter-vehicle distance detection/warning device that issues an alarm when the inter-vehicle distance becomes smaller than a safe inter-vehicle distance determined based on the braking distance and free running distance of the own vehicle, the inter-vehicle distance is smaller than a predetermined value. An inter-vehicle distance detection/warning device characterized by controlling headlamps to perform passing when [Claim 2] Determine the inter-vehicle distance by detecting the time it takes for a laser beam emitted from the own vehicle to be reflected by the vehicle in front and return;
In an inter-vehicle distance detection/warning device that issues an alarm when the inter-vehicle distance becomes smaller than a safe inter-vehicle distance determined based on the braking distance and free running distance of the own vehicle, the inter-vehicle distance is smaller than a predetermined value. An inter-vehicle distance detection/warning device characterized by controlling an electric horn to sound when the distance is exceeded.