JP2850534B2 - Rear-end collision prevention device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear-end collision prevention device, and more particularly to a rear-end collision prevention device that issues an early warning of a short inter-vehicle distance.

[Conventional technology]

As a device for preventing a rear-end collision of a vehicle, a stop lamp that is lit when a driver depresses a brake pedal is extremely common, and when a stop lamp of a preceding vehicle is lit,
In the latter case, the driver visually recognizes the lighting of the stop lamp to judge the reduction of the inter-vehicle distance, and performs a deceleration operation such as depressing a brake pedal to prevent a rear-end collision.

However, in the rear-end collision prevention operation of the driver of the rear vehicle by visually checking the stop lamp lighting, the deceleration operation is delayed if the latter driver is looking aside, and it is difficult to prevent the rear-end collision especially at high speed traveling. Would.

To solve this drawback, Japanese Patent Laid-Open Publication No.
There are those disclosed in JP-A-56-135351 and JP-A-58-156874.

Of these conventional examples, in the device proposed in Japanese Patent Application Laid-Open No. 56-135351, a signal wave is transmitted, and the distance from the reflected wave from an obstacle or the like (including another vehicle) to the obstacle or the like is determined. A change is detected, and the frequency of the alarm sound is changed in accordance with the change to notify the driver of a change in the distance to an obstacle or the like.

Also, in the device disclosed in Japanese Patent Application Laid-Open No. 58-156874, an optical signal is transmitted from a first mobile body, reflected light from a second mobile body approaching is received, and a time difference between transmission and reception is calculated. A change in the distance between the two moving bodies is detected, and when approaching within a predetermined distance, an alarm signal is transmitted to the second moving body to recognize the approach.

[Problems to be solved by the invention]

However, the former conventional example is configured to continuously detect a change in the distance between vehicles and continuously issue an alarm, and thus is not suitable for the purpose of preventing a danger of a rear-end collision.

Also, in the latter conventional example, when the distance becomes less than a certain inter-vehicle distance, the system is also configured to continue to issue an alarm, so that during a traffic jam etc., unless a special switch is turned off,
The alarm will sound off, and if the switch is turned off, the function of preventing rear-end collision will not be possible. Further, since the reference inter-vehicle distance is always constant and the vehicle speed of the front vehicle and the rear vehicle is not taken into consideration, there is a risk of rear-end collision depending on the vehicle speed of both vehicles.

Therefore, an object of the present invention is to provide a rear-end collision prevention device that can warn the front vehicle and the rear vehicle in advance only when the reduction of the inter-vehicle distance is necessary.

[Means for solving the problem]

In order to solve the above problem, in a rear-end collision prevention device according to the present invention, a means for detecting the start of a deceleration operation of a driver, a transmission means for transmitting a signal notifying the start of the deceleration operation to the latter, The rear receiving means for receiving the reflected signal in the latter, the alarm means, the own vehicle speed detecting means, the inter-vehicle distance calculated from the reflected signal is calculated based on the rear vehicle speed and the own vehicle speed based on the reflected signal. Determining means for issuing an alarm by the alarm means when it is determined that the distance is equal to or less than a reference inter-vehicle distance obtained from a built-in map.

Further, in the present invention, it is possible to further include a front receiving unit that receives the transmission signal from the front vehicle and notifies the driving vehicle of the start of the deceleration operation of the front vehicle by the alarm unit.

[Action]

In the present invention, when the driver's deceleration operation start detection means is activated, the transmission means receives this deceleration operation start signal and transmits a signal to the rear vehicle.

Then, the judging means, which has received the reflected signal from the rear vehicle via the rear receiving means, detects the vehicle speed and the inter-vehicle distance of the rear vehicle from the reflected signal and the transmitted signal, and detects the detected vehicle speed of the rear vehicle. And a reference vehicle distance obtained from a built-in map based on the vehicle speed detected by the vehicle speed detection means.

As a result, when it is determined that the current inter-vehicle distance is equal to or less than the reference inter-vehicle distance, an alarm is issued to the own vehicle and the rear vehicle via the alarm means.

Therefore, it is possible to notify the driver of the front vehicle of the risk of a rear-end collision according to the inter-vehicle distance corresponding to the vehicle speed of the front vehicle and the rear vehicle.

Further, in the present invention, when the transmission signal is transmitted from the front vehicle, the transmission signal is received by the front reception unit of the rear vehicle, and the start of the deceleration operation of the front vehicle is notified to the driver of the rear vehicle by the alarm unit. Can be immediately notified of the danger of rear-end collision.

〔Example〕

FIG. 1 is a block diagram showing the configuration of an embodiment of a rear-end collision prevention device according to the present invention. In FIG. 1, reference numeral 1 denotes an accelerator pedal (not shown) having a depression amount of zero or a value corresponding thereto. The accelerator switch which is turned on when the vehicle is turned on, the brake switch which is turned on when a brake pedal (not shown) is depressed, the vehicle speed sensor 3 as a vehicle speed detecting means for the own vehicle, the accelerator switch 1 or the brake switch 2 which is When it is turned on, it is an OR gate that sends a signal to the transmitter 5, and together with the accelerator switch 1 and the brake switch 2, constitutes a means for detecting the start of deceleration operation of the driver.

Reference numeral 6 denotes a deceleration operation start signal 9 from the transmitter 5 (hereinafter, referred to as “deceleration operation start signal 9”).
(Which may be simply referred to as a signal 9) toward the rear vehicle 10, and constitutes transmitting means together with the transmitter 5. Reference numeral 7 denotes a lamp which is turned on when the brake switch 2 is turned on, 8 denotes an alarm lamp which is turned on by a signal from a CPU 20, which will be described later, and 12 denotes a rear reception which receives a signal 9 reflected by the rear vehicle 10 via a rear reception antenna 11. And constitutes a rear receiving means together with the rear receiving antenna 11.

Reference numeral 14 denotes a front receiver for receiving the signal 9 from a front vehicle (not shown) via the front receiving antenna 13, and constitutes a front receiving means together with the front receiving antenna 13. Reference numeral 15 denotes a buzzer as a warning means together with the lamps 7 and 8 and the display 16, and reference numeral 20 denotes a CPU as a determination means provided with a Doppler radar 21 and a map 22, as shown in FIG.

 Next, the operation of the above embodiment will be described.

First, when the driver returns the accelerator pedal for the deceleration operation and makes the depression amount zero, or depresses the brake pedal, the accelerator switch 1 or the brake switch 2 is turned on and the transmitter 5 is energized to perform the deceleration operation. A start signal 9 is generated.

At this time, the signal 9 is transmitted from the transmitter 5 to the CPU 20 and transmitted to the rear vehicle 10 via the transmission antenna 6.

On the other hand, the rear receiver 12 that has received the signal 9 reflected by the rear vehicle 10 via the receiving antenna 11 at the rear thereof outputs the signal 9 to the CPU 20.
To send to.

Then, the CPU 20 compares the signal 9 from the transmitter 5 and the signal 9 from the rear receiver 12 in the well-known Doppler radar 21 as shown in FIG. m ₁ and obtaining the other vehicle speed v _2.

Then, a reference inter-vehicle distance m ₀ corresponding to the other vehicle speed v ₂ and the own vehicle speed v ₁ detected by the vehicle speed sensor 3 is obtained from a map 22 shown in FIG. 3, and the reference inter-vehicle distance m ₀ and the current inter-vehicle distance are calculated. It is compared with the m _1.

As a result, if it is determined that m ₀ > m ₁ , the lamp 8 flashes to warn the driver of the rear vehicle 10 of an inter-vehicle distance reduction, and the buzzer 15 is sounded and displayed on the display 16 to drive the own vehicle. Alerts the driver to reduce the distance between vehicles.

The map 22 shown in FIG. 3 shows the vehicle speed v ₁ of both vehicles by the experiment.
A and v ₂ can be created by asking the following distance m ₀ corresponding.

The front receiver 14 which has received the signal 9 from the front vehicle via the front reception antenna 13 sends the signal 9 to the buzzer 15 and the display 16 so that the driver of the own vehicle can perform the deceleration operation of the front vehicle driver. Alert immediately to start.

The above-described embodiment is operated during parking, and when there is a possibility of a rear-end collision based on the vehicle speed and the inter-vehicle distance of a vehicle approaching from behind, the lamp 8 flashes to improve the visibility of the parked vehicle. In the approaching vehicle, an air piston operated by a signal 9 from a parked vehicle is provided on the driver's seat, and when there is a possibility of a rear-end collision, the driver reciprocates by the air piston according to the signal 9. The seat may be vibrated up and down, and the driver may sense danger by the seat vibration.

[Effects of the Invention] As described above, in the rear-end collision prevention device according to the present invention, the start of the deceleration operation of the driver is transmitted to the rear vehicle,
Since the reflected signal is received, the inter-vehicle distance and the rear vehicle speed are obtained, and the reference inter-vehicle distance and the inter-vehicle distance obtained from the map are compared with the post-vehicle speed and the own vehicle speed to issue an alarm. Only when the driver needs to start the deceleration operation, it is possible to prevent the rear-end collision corresponding to the front vehicle speed and the rear vehicle speed.

In addition, the start of deceleration operation of the front vehicle is notified to the driver of the rear vehicle by the alarm means in response to a transmission signal from the front vehicle, so that the start of deceleration operation of the front vehicle can be immediately notified to the driver of the rear vehicle. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a rear-end collision prevention apparatus according to the present invention. FIG. 2 is a block diagram showing a configuration of a determination unit of an embodiment of the rear-end collision prevention apparatus according to the present invention. FIG. 3 is a map diagram of vehicle speed and inter-vehicle distance used in the rear-end collision prevention device according to the present invention. In the figure, 1, 2 and 4 are accelerator switches, brake switches and OR gates as means for detecting the start of deceleration operation by the driver, 3 is a vehicle speed sensor, 5 and 6 are transmitters and antennas as transmitting means, 7, 8, 15 And 16 are lamps, buzzers and displays as alarm means, 11, 12, 13
And 14 indicate an antenna and a receiver as front and rear receiving means, respectively, and 20 indicates a CPU as a determining means, respectively. In the drawings, the same reference numerals indicate the same or corresponding parts.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) G01S 13/93 G01S 15/93 G01S 17/88 G08G 1/16

Claims (2)

(57) [Claims] Means for detecting the start of a deceleration operation by a driver;
Transmitting means for transmitting a signal notifying the start of the deceleration operation to the rear vehicle, rear receiving means for receiving a reflected signal from the rear vehicle, alarm means, own vehicle speed detecting means, and the reflected signal Determination means for issuing an alarm by the alarm means when it is determined that the inter-vehicle distance calculated from is within the reference inter-vehicle distance obtained from a built-in map based on the vehicle speed and the host vehicle speed calculated from the reflection signal. Back-end collision prevention device characterized by the above-mentioned. 2. The vehicle according to claim 1, further comprising a front receiving means for receiving the transmission signal from the preceding vehicle and informing the driver of the start of deceleration operation of the preceding vehicle to the driver by an alarm means. apparatus.