JP3752871B2 - Brake lamp control device for automobile - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a brake lamp control device having a function of lighting a brake lamp of an automobile.
[0002]
[Prior art]
Conventionally, a brake lighting system has been proposed that automatically turns on the brake lamp when the user quickly removes his or her foot from the accelerator pedal as a means to quickly notify the driver of the following vehicle of the braking operation (rapid braking, etc.) while the vehicle is running. Has been. This type of brake lighting system is equipped with an accelerator sensor that outputs a signal related to the operation of the accelerator pedal, and it is estimated that the brake pedal is stepped on when the return speed of the accelerator pedal exceeds a predetermined threshold value. Then, by operating the brake lamp lighting circuit, the brake lamp is automatically lit in advance before the driver steps on the brake pedal. However, just because the accelerator pedal is quickly returned does not necessarily depress the brake pedal.
[0003]
[Problems to be solved by the invention]
In the prior art brake lamp lighting system, since the brake lamp is lit only on the basis of the speed at which the accelerator returns, the brake lamp is automatically lit even though the driver does not step on the brake pedal. There is a possibility that the following vehicle will be confused.
[0004]
Accordingly, an object of the present invention is to provide an automobile brake lamp control device that can accurately estimate whether or not the brake pedal is stepped on and automatically turn on the brake lamp more appropriately.
[0005]
[Means for Solving the Problems]
A brake lamp control device for an automobile according to the present invention includes an inter-vehicle distance sensor that measures a distance from the host vehicle to a preceding vehicle, a vehicle speed sensor that detects a speed of the host vehicle, an accelerator sensor that detects an accelerator operation, and the accelerator sensor. When the accelerator return speed detected by the vehicle exceeds a predetermined threshold value and the inter-vehicle distance detected by the inter-vehicle distance sensor is shorter than a reference inter-vehicle distance set to increase as the vehicle speed increases, a brake lamp A control means for activating a lighting circuit to light a brake lamp and not lighting the brake lamp when the inter-vehicle distance is longer than the reference inter-vehicle distance even if the acceleration return speed exceeds the threshold value; is doing. The control means of the present invention takes into consideration the reference inter-vehicle distance according to the vehicle speed as well as the speed at which the accelerator returns, as a judgment material for estimating whether or not the brake pedal is depressed. That is, when the accelerator returns quickly and the actual inter-vehicle distance measured at that time does not reach the reference inter-vehicle distance according to the vehicle speed, the driver depresses the brake pedal, and the brake lamp lighting circuit is activated. The brake lamp is turned on automatically.
[0006]
The control means is a timer for turning on the brake lamp for a predetermined time (for example, 1 second) so that the brake lamp can be automatically turned off when the brake pedal is not depressed after the brake lamp is automatically turned on. It is good to have a function. If the brake pedal is depressed within the predetermined time, the brake lamp is kept on by the brake switch linked to the brake pedal.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to an automobile brake lamp control device 10 shown in FIG.
The brake lamp control device 10 includes an inter-vehicle distance sensor 11 that measures a distance from the host vehicle to a preceding vehicle, a vehicle speed sensor 12 that detects a speed of the host vehicle, an accelerator sensor 13 that detects an accelerator operation, a brake A lamp lighting circuit 14 and control means 15 that uses a part of the functions of an engine control computer or the like are provided.
[0008]
The inter-vehicle distance sensor 11 has a function of measuring the distance from the host vehicle to the preceding vehicle by, for example, emitting a laser beam or radio wave in front of the host vehicle and capturing the reflected wave with a receiver. The accelerator sensor 13 outputs an electrical signal related to the amount of movement of the accelerator pedal 20 (the amount of change in the accelerator opening).
[0009]
The brake lamp lighting circuit 14 has a function of turning on the brake lamp 32 by turning on the brake switch 31 when the driver steps on the brake pedal 30 and causing the brake lamp 32 to turn on. It also has a function of lighting the brake lamp 32 by turning on the relay 33 when the brake lamp lighting signal is transmitted.
[0010]
The control means 15 determines that the accelerator return speed (differential value) detected by the accelerator sensor 13 exceeds a predetermined threshold, and the actual inter-vehicle distance detected by the inter-vehicle distance sensor 11 depends on the vehicle speed. When the distance is shorter than the reference inter-vehicle distance, the brake lamp lighting signal is output to the brake lamp lighting circuit 14 for T seconds.
[0011]
The reference inter-vehicle distance referred to in this specification is an inter-vehicle distance (so-called safe inter-vehicle distance) that the driver determines that the vehicle is too close to the vehicle ahead only by engine braking, and the reference inter-vehicle distance increases as the vehicle speed increases. Becomes longer. The relationship between the reference inter-vehicle distance and the vehicle speed is obtained in advance, for example, mapped and stored in the memory of the computer of the control means 15.
[0012]
When the driver performs a brake operation, it is known that it takes about one second after the foot is released from the accelerator pedal 20 until the brake pedal 30 is depressed and the braking force is actually generated. Therefore, in this embodiment, after the brake lamp 32 is automatically turned on by the control means 15, it is determined that there is no intention to apply the brake when the brake pedal 30 is not depressed even after T seconds (for example, 1 second) elapses. A timer 34 for turning off the brake lamp 32 is provided.
[0013]
Next, the operation of the brake lamp control device 10 having the above configuration will be described with reference to the flowchart shown in FIG.
When it is necessary to apply the brake according to the traveling state of the vehicle, when the driver removes his / her foot from the accelerator pedal 20 and tries to step on the brake pedal 30, the accelerator pedal 20 first returns and the accelerator sensor 13 The speed at which the accelerator returns (differential value) is detected. In the situation where the brake is applied, the accelerator pedal 20 is quickly returned. Therefore, in the accelerator determination step ST1, the speed at which the accelerator returns is compared with a predetermined threshold value. If the threshold value is exceeded, the inter-vehicle distance determination step ST2 is performed. Move.
[0014]
In the inter-vehicle distance determination step ST2, the actual inter-vehicle distance detected by the inter-vehicle distance sensor 11 is compared with the reference inter-vehicle distance, and when the actual inter-vehicle distance is shorter than the reference inter-vehicle distance, a signal for lighting the brake lamp 32 is given. It is output to the brake lamp lighting circuit 14. For this reason, before the driver steps on the brake pedal 30, the brake lamp 32 is lit in advance, and the subsequent vehicle can be alerted. In particular, it is possible to notify that the following vehicle is quickly braked at the time of a brake operation in which a time difference from when the accelerator pedal 20 is released to when the brake switch 31 is actually turned on becomes a problem, such as sudden braking.
[0015]
In this embodiment, the brake lamp 32 can be turned on as early as 0.5 to 1 second before the brake pedal 30 is actually depressed and the brake switch 31 is turned on after the accelerator pedal 20 is returned. Thus, the brake lighting system is more effective for preventing the rear-end vehicle from colliding.
[0016]
The control means 15 does not estimate the brake operation based on only the speed at which the accelerator returns, but operates the brake lamp lighting circuit 14 including the relationship between the actual inter-vehicle distance and the reference inter-vehicle distance in the judgment material. Therefore, it is possible to more accurately estimate whether or not the driver steps on the brake pedal, and it is possible to avoid the brake lamp from being unnecessarily lit.
[0017]
In addition, in this embodiment, after the brake lamp 32 is automatically turned on by the control means 15, the brake lamp 32 is turned off by the timer 34 when the brake pedal 30 is not depressed even after T seconds elapses. When it is erroneously estimated that the brake pedal is stepped on (when the brake lamp 32 is automatically turned on when the driver does not press the brake pedal), the brake lamp 32 may be turned off in a short time. it can. For this reason, it is also possible to avoid annoying the following vehicle.
[0018]
In this way, the control means 15 automatically turns on the brake lamp 32 for T seconds (for example, 1 second). If the brake pedal 30 is depressed within this T seconds, the brake switch 31 is turned on to turn on the brake lamp 32. Is maintained.
[0019]
In the inter-vehicle distance determination step ST2 shown in FIG. 2, the actual inter-vehicle distance is shorter than the reference inter-vehicle distance, and the relative speed between the host vehicle and the preceding vehicle (the speed in the direction approaching each other) has a predetermined threshold value. The control means 15 may be configured to automatically turn on the brake lamp 32 for T seconds when it exceeds the limit.
[0020]
In carrying out the present invention, it goes without saying that the constituent elements including the inter-vehicle distance sensor, the vehicle speed sensor, the accelerator sensor, the brake lamp lighting circuit, and the control means constituting the present invention can be appropriately modified and implemented.
[0021]
【The invention's effect】
According to the first aspect of the present invention, since the brake lamp can be automatically turned on in advance before the driver steps on the brake pedal, it is possible to call attention to the succeeding vehicle, and whether or not to press the brake pedal. Since the estimation can be performed with high accuracy, it is possible to prevent the brake lamp from being turned on unnecessarily.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a circuit configuration of a brake lamp control device showing an embodiment of the present invention.
FIG. 2 is a flowchart showing the function of the control means of the brake lamp control device shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Brake lamp control apparatus 11 ... Inter-vehicle distance sensor 12 ... Vehicle speed sensor 13 ... Accelerator sensor 14 ... Brake lamp lighting circuit 15 ... Control means

Claims (2)

An inter-vehicle distance sensor that measures the distance from the host vehicle to the vehicle ahead,
A vehicle speed sensor for detecting the speed of the host vehicle;
An accelerator sensor that detects accelerator operation;
When the acceleration speed of the accelerator detected by the accelerator sensor exceeds a predetermined threshold and the inter-vehicle distance detected by the inter-vehicle distance sensor is shorter than a reference inter-vehicle distance that is set to increase as the vehicle speed increases. A control means for activating the brake lamp lighting circuit to turn on the brake lamp and not turning on the brake lamp when the inter-vehicle distance is longer than the reference inter-vehicle distance even if the acceleration return speed exceeds the threshold value. When,
A brake lamp control device for an automobile, comprising:   The control means turns on a brake lamp when the inter-vehicle distance is shorter than the reference inter-vehicle distance and the relative speed in the direction in which the host vehicle and the preceding vehicle approach each other exceeds a predetermined threshold value. The brake lamp control device for an automobile according to claim 1.

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