JPH10297355A - Headlamp control device and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To light headlamps automatically when the illuminance around a vehicle is made less than a specific brightness, and at the same time, to prevent the lighting of the headlamp when the reduction of the illuminance in the periphery is in a short time. SOLUTION: A headlamp control device 1 consists of a main body 9 to carry out the lighting and the lights-out control of headlamps 3 and 5, and a tail lamp 7; and a power feeding part 11 to feed the power to the main body 9. When the lighting controller 43 of the central control part 29 of the main body 9 detects that the illuminance around a vehicle detected by a photodiode 25 is made less than the lighting illuminance to light the headlamps 3 and 5 through a night detector 39, it lights the headlamps 3 and 5 through a transistor TR3, only when the brightness less than the lighted illuminance continues for a specific time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headlamp control device and a control method for automatically turning on a vehicle headlamp.

[0002]

2. Description of the Related Art A headlamp control device for detecting illuminance around a vehicle using a light receiving element such as a photodiode and automatically turning on and off a headlamp based on the detected illuminance has been used.

[0003]

However, in the conventional headlamp control device, when the illuminance around the vehicle reaches a predetermined lighting illuminance for lighting the headlamp,
Since the headlamps are turned on immediately,
Even if the vehicle passes through a shaded area such as under a bridge or an elevated road during the daytime and the surrounding illuminance becomes dark for a short time, the headlamps may be turned on automatically. There is a problem that is very depressing.

[0004] In view of the above problems, the present invention can automatically turn on the headlamp when the illuminance around the vehicle falls below a predetermined brightness, and the illuminance around the vehicle is reduced for a short time. In such a case, an object of the present invention is to provide a headlamp control device and a control method capable of preventing headlamp lighting.

[0005]

Technical means for achieving the above object are illuminance detecting means for detecting illuminance around the vehicle, switching means for turning on / off a headlamp, and illuminance detecting means. Based on the detected illuminance detected by the controller, the switching unit is instructed to light the headlamp only when the state in which the detected illuminance is equal to or less than the predetermined lighting illuminance for lighting the headlamp continues for a predetermined time. And control means.

Preferably, the control means includes a lighting control section and a light-off control section for giving an instruction to turn on and off a headlamp to the switching means based on the detected illuminance detected by the illuminance detecting means. The lighting control unit is configured to receive an instruction to turn off the headlamp from the light-off control unit to the switching unit, and to start a counting operation for a first predetermined time as the headlamp is turned off. A first timer unit and a second timer unit when the detected illuminance becomes equal to or less than the predetermined lighting illuminance.
A second timer unit that starts a counting operation for a predetermined time, and when the detected illuminance is equal to or less than the predetermined lighting illuminance,
It is determined whether or not the count operation of the first timer section has been completed. If the count operation of the first timer section has been completed, an instruction to turn on a headlamp is given to the switching means. If the count operation of the first timer section is not completed, the state where the detected illuminance is equal to or less than the predetermined lighting illuminance continues while the count operation of the second timer section is continued. And a lighting instruction unit for giving an instruction to turn on the headlamp to the switching means only when the switching is performed.

Further, a technical means for achieving the above object is to detect illuminance around the vehicle by illuminance detecting means, and when the detected illuminance falls below a predetermined lighting illuminance for turning on the headlamp, A headlamp control method for controlling a switching means for controlling on / off of the headlamp to light the headlamp, wherein the detected illuminance detected by the illuminance detection means is equal to or less than the predetermined lighting illuminance. The headlamp is turned on through the switching means only when a predetermined time has elapsed.

[0008]

FIG. 1 is a block diagram showing an electrical configuration of a headlamp control device according to an embodiment of the present invention. The headlamp control device 1 includes a headlamp 3,
A main unit 9 for controlling turning on and off of the tail lamp 5 and the tail lamp 7 and a power supply unit 11 for supplying electric power from a battery 10 to the main unit 9 are provided. In the figure, 1
Reference numeral 3 denotes a light switch.
Is set to the auto light position, the contact P
1 is connected to the ground, and the headlamp controller 1 automatically switches on and off the headlamps 3 and 5 and the taillight 7. In addition to the auto light position, the light switch 13 has contacts P2 to P4 corresponding to the off position, the head lamp position for manually turning on and off the head lamps 3, 5 and the tail lamp 7, and the tail lamp position.
Is provided. The headlamps 3 and 5 are provided for a high beam and a low beam, and can be switched by a dimmer switch 15.

In the power supply unit 11, when the input signal to the set (S) terminal of the flip-flop 19 becomes high level by turning on the ignition switch 17, the input signal from the logic circuit 21 to the reset (R) terminal is changed. Regardless, the output of the queue (Q2) of the flip-flop 19 goes low (see the truth table of the flip-flop 19 in FIG. 2), and accordingly, the transistor TR1 is turned on, and the power from the battery 10 is turned off. It is supplied to the section 9. After the power supply to the main body 9 is started,
Even if the ignition switch 17 is turned off, the power supply to the main body 9 is not stopped immediately, and the power supply is stopped after the operation door is opened. That is, when the driver's seat door is opened, the courtesy switch 23 is turned on, the reset (R) input from the logic circuit 21 becomes high level, the output of the cuba (Q2) switches to high level, and Is turned off.

The main body 9 includes a photodiode 25 (illuminance detecting means) for detecting the illuminance around the vehicle, and a transistor TR2 as a switching means based on a signal input from the photodiode 25 via an amplifier 27.
And a central control unit 29 (control means) for controlling ON / OFF of the tail lamp 7 and the head lamps 3 and 5 via the TR 3.

When a high-level signal is input from the central control unit 29 to the transistor TR2, a current from the battery 10 flows to the ground via the relay coil 33a of the relay 33, the transistor TR2, and the contact P1 of the light switch 13. The switch 33b of the relay 33
Turns on, and the tail lamp 7 is turned on. The tail lamp 7 thus lit is turned off when a low-level signal is input from the central control unit 29 to the transistor TR2.

Similarly, when a high-level signal (headlamp lighting signal) is input from the central control unit 29 to the transistor TR3, the current from the battery 10
Flows through the relay coil 35a, the transistor TR3, and the contact P1 of the light switch 13 to the ground, and accordingly, the switch 35b of the relay 35 is turned on, and the head lamp 3 or 5 is turned on. The headlamp 3 or 5 thus lit is extinguished when a low-level signal (headlamp extinguishment signal) is input from the central control unit 29 to the transistor TR3.

The central control unit 29 includes a CPU, a memory, and the like, and includes a twilight detecting unit 37 for controlling the tail lamp 7, a night detecting unit 39 for controlling the head lamps 3, 5, and a delay processing unit. 41. As shown in FIG. 3A, the twilight detection unit 37 determines whether the detected illuminance detected by the photodiode 25 is the tail lamp 7.
1st lighting illuminance L1 (about 130 lux) to be turned on
When the brightness becomes lower than the first lighting illuminance L1 or lower, the transistor T
The twilight detection signal output to the base of R2 is switched from a low level to a high level. Conversely, when the detected illuminance is less than the first illuminance L2 (about 550 lux) at which the tail lamp 7 should be extinguished, it becomes equal to or more than the first illuminance L2. Then, the dusk detection signal is switched from the high level to the low level so that the tail lamp 7 is turned off.

As shown in FIG. 3 (b), the night detecting section 39 determines that the detected illuminance detected by the photodiode 25 is the second lighting illuminance L3 for turning on the headlamps 3 and 5.
(About 50 lux) from the second lighting illuminance L3
When it becomes less than the above, the night detection signal output to the delay processing unit 41 is switched from the low level to the high level, and conversely, the detected illuminance is lower than the second illuminance L4 (about 200 lux) at which the headlamps 3 and 5 should be extinguished. When the second turn-off illuminance L4 or more, the night detection signal is switched from a high level to a low level.

As shown in FIG. 4, the delay processing section 41 includes a lighting control section 43 that functions when the headlamps 3 and 5 are turned on, and a light-off control section 45 that functions when the headlamps 3 and 5 are turned off. ing.

The lighting control unit 43 includes a first timer unit 47,
A second timer unit 49 and a lighting instruction unit 51 are provided. Among them, the first timer unit 47 outputs a headlamp extinguishing signal to the transistor TR3 from the extinguishing control unit 45 described later, and extinguishes the headlamps 3 and 5. Alternatively, if the headlamp extinguishing signal is input to the transistor TR3 and the headlamps 3 and 5 are extinguished, the detected illuminance changes from less than the second extinguished illuminance L4 to the second illuminated illuminance L4 or more, and the night detection signal is output. Is switched from a high level to a low level, a counting operation for a first predetermined time is started.

The second timer unit 49 includes a transistor TR
In the state where the headlamp extinguishing signal is input to 3 and the headlamps 3 and 5 are extinguished, when the detected illuminance becomes equal to or less than the second lighting illuminance L3 and the nighttime detection signal switches from a low level to a high level, The counting operation for the second predetermined time is started.

When the headlamp extinguishing signal is inputted to the transistor TR3 and the headlamp 3 and 5 are turned off, the lighting instructing section 51 detects the switching of the night detection signal from low level to high level. It is determined whether or not the counting operation of the first timer unit 47 has been completed. If the counting operation of the first timer unit 47 has been completed, the headlamp lighting for instructing the lighting of the headlamps 3 and 5 is performed. Immediately apply the signal to transistor TR
3, while the count operation of the first timer unit 47 is not completed, the state in which the night detection signal is at the high level is the time until the count operation of the second timer unit 49 is completed. The headlamp lighting signal is output to the transistor TR3 only when the operation is continued, and the headlamp 3 and 5 are lit.

The light-off control section 45 includes a third timer section 53 and a light-off instruction section 55. Third timer unit 53
In the state where the headlamp lighting signal is input to the transistor TR3 and the headlights 3 and 5 are lit, the detected illuminance becomes equal to or higher than the second unlit illuminance L4, and the night detection signal switches from the high level to the low level. Then, the counting operation for the third predetermined time is started.

When the headlamp lighting signal is input to the transistor TR3 and the headlamp 3 or 5 is illuminated, the light-off instruction unit 55 detects the switching of the night detection signal from the high level to the low level when it is detected. The state where the night detection signal is at the low level is the third state.
Only when the count operation of the timer section 53 is continued until the count operation of the third timer section 53 is completed, a headlamp extinguishment signal is output to the transistor TR3 to give an instruction to turn off the headlamp 3 and 5. If the detected illuminance becomes equal to or higher than the first extinguishing illuminance L2 before the operation is completed and the switch to the low level of the twilight detection signal is detected, the headlamp extinguishing signal is immediately output to the transistor TR3. .

FIGS. 5 and 6 are flowcharts relating to the control of the headlamps 3 and 5 of the central control unit 29.
In the figure, steps S1 to S10 are processes performed by the light-off control unit 45, and steps S11 to S19 are processes performed by the lighting control unit 43.

When the light switch 13 is set to the automatic position in a state where power is supplied to the main body 9, the headlamp control device 1 starts turning on and off the headlamps 3 and 5 and the taillight 7. Is done.

First, in step S1, it is determined whether the detected illuminance is equal to or less than the second lighting illuminance L3. When the detected illuminance is equal to or less than the second lighting illuminance L3, the head lamps 3, 5 are turned on in step S2. Proceed to step S3.

In step S3, it is determined whether or not the detected illuminance is equal to or greater than the second unlit illuminance L4. When the detected illuminance is equal to or greater than the second unlit illuminance L4, the counting operation of the third timer unit 53 is started in step S4. Then, the process proceeds to step S5. In step S5, it is determined whether or not the detected illuminance is equal to or less than the second lighting illuminance L3. If the detected illuminance is not less than or equal to the second lighting illuminance L3, the process proceeds to step S6, where the detected illuminance becomes equal to or less than the second lighting illuminance L3. If yes, the counting operation of the third timer unit 53 is stopped (step S7), and the process returns to step S3.

In step S6, it is determined whether or not the detected illuminance is equal to or greater than the first turn-off illuminance L2.
Is stopped (step S8), the headlamps 3 and 5 are turned off (step S9). If the illuminance is not equal to or higher than the first turn-off illuminance L2 in step S6, the process proceeds to step S10. In step S10, it is determined whether or not the count operation of the third timer unit 53 has been completed. If the count operation has been completed, the process proceeds to step S9, where the headlamps 3 and 5 are turned off. Returning to step S5, the processing of steps S5, S6, and S10 is repeated until the counting operation ends.

When the headlamps 3 and 5 are turned off in step S9, the first timer unit 47 is switched in step S11.
Is started, the process proceeds to step S12, and it is determined whether the detected illuminance is equal to or less than the second lighting illuminance L3. If the detected illuminance is equal to or less than the second lighting illuminance L3, the process proceeds to step S13. If not, the process waits until the second lighting illuminance L3 or less.

In step S13, the first timer unit 47
It is determined whether or not the counting operation has been completed. If the counting operation has been completed, the head lamps 3 and 5 are turned on (step S14), and if not, the counting operation of the first timer unit 47 is started. The operation is stopped (step S15), the count operation of the second timer unit 49 is started (step S16), and the process proceeds to step S17.

In step S17, it is determined whether or not the detected illuminance is equal to or greater than the second unlit illuminance L4. If the detected illuminance is equal to or greater than the second unlit illuminance L4, the counting operation of the second timer unit 49 is stopped. (Step S18) The process returns to step S11, and if the illuminance is not equal to or higher than the second turn-off illuminance L4, the process proceeds to step S19.

In step S19, the second timer unit 49
It is determined whether or not the counting operation has been completed. If the counting operation has been completed, the head lamps 3 and 5 are turned off (step S14), and if not, the step S17 has been completed.
Then, the processing of steps S17 and S19 is repeated until the counting operation of the second timer unit 49 ends.

When the headlamps 3 and 5 are turned on in step S14, the process returns to step S3, and the processes in steps S3 to S19 are repeated.

FIG. 7 is a timing chart showing how the headlamp control device 1 controls the turning on and off of the head lamps 3, 5 and the tail lamp 7 in response to a change in the illuminance around the vehicle.

When the surrounding illuminance, which had exceeded the first extinguishing illuminance L2 at the start of operation of the headlamp control device 1 (time T0), becomes equal to or less than the first illuminating illuminance L1 at time T1, the twilight detection signal changes from the low level. When the illuminance of the surroundings falls below the second lighting illuminance L3 at time T2, the night detection signal changes from a low level to a high level, whereby the transistor TR2 is turned on. TR3 is turned on, and headlamps 3 and 5 are turned on (step S2).

At time T3, the surrounding illuminance is changed to the second unlit illuminance L.
When the number becomes 4 or more, the night detection signal changes from the high level to the low level, and accordingly, the counting operation of the third timer unit 53 of the light-off control unit 45 is started (step S4).
When the surrounding illuminance becomes equal to or less than the second lighting illuminance L3 at time T4 before the counting operation ends, the night detection signal changes from the high level to the low level, and accordingly, the counting operation of the third timer unit 53 stops. (Step S8)
The lighting state of the headlamps 3 and 5 is maintained.

At time T5, when the surrounding illuminance again becomes equal to or higher than the second non-illumination illuminance L4, the night detection signal changes from the high level to the low level, and the counting operation of the third timer unit 53 is started accordingly (step S4). ), The headlamp 3 and 5 are stopped as the counting operation ends at time T6.
Is turned off (step S9), and the counting operation of the first timer unit 47 of the lighting control unit 43 is started (step S9).
11).

After the count operation of the first timer section 47 is completed at time T7, when the surrounding illuminance becomes equal to or less than the second lighting illuminance L3 at time T8, the night detection signal changes from low level to high level. The headlamps 3 and 5 are turned on (step S14).

When the surrounding illuminance becomes equal to or higher than the second non-lighting illuminance L4 at time T9, the night detection signal changes from the high level to the low level.
The counting operation of the timer unit 53 is started (step S
4) At time T10 before the counting operation ends,
When the surrounding illuminance is equal to or greater than the first unlit illuminance L2, the twilight detection signal changes from the high level to the low level, and accordingly, the counting operation of the second timer unit 49 is stopped (step S8), and the headlamp 3 , 5 and the tail lamp 7 are turned off (step S9), and the count operation of the first timer unit 47 is started (step S11).

After the count operation of the first timer unit 47 is completed at time T11, when the ambient illuminance suddenly changes from the first illuminance L2 or higher to the second illuminance L3 or lower at time T12, the dusk detection signal and the nighttime The detection signal changes from the low level to the high level, and accordingly, the tail lamp 7 and the head lamps 3, 5 are turned on (step S1).
4) At time T13, the surrounding illuminance is changed to the second lighting illuminance L3 again.
If the illuminance suddenly changes from the following to the first extinction illuminance L2 or more, the twilight detection signal and the night detection signal change from the high level to the low level, and the third timer unit 53 is turned off immediately after being turned on (steps S4, S5, S6). S8) Then, the tail lamp 7 and the head lamps 3 and 5 are turned off (step S9), and the counting operation of the first timer unit 47 is started (step S11).

At time T14 before the end of the counting operation of the first timer section 47, when the surrounding illuminance suddenly changes to the second lighting illuminance L3 or less, the twilight detection signal and the night detection signal change from low level. High level,
With the head lamps 3 and 5 kept off, the tail lamp 7 is turned on, the counting operation of the first timer unit 47 is stopped (step S15), and the counting operation of the second timer unit 49 is started (step S16).

Second timer section 4 started at time T14
At time T15 before the end of the counting operation of No. 9, when the surrounding illuminance sharply changes to the first extinction illuminance L2 or more, the twilight detection signal and the night detection signal change from the high level to the low level, and the tail lamp 7 is turned off. And the second
The counting operation of the timer unit 49 is stopped (step S
18), the counting operation of the first timer unit 47 is started (step S11).

The time T16 before the end of the counting operation of the first timer unit 47 started at the time T15.
When the ambient illuminance suddenly changes below the second lighting illuminance L3, the twilight detection signal and the night detection signal change from low level to high level, and accordingly, the headlamps 3, 5
Is turned off, the tail lamp 7 is turned on, the counting operation of the first timer unit 47 is stopped (step S15), the counting operation of the second timer unit 49 is started (step S16), and time 17 is reached. Then, the head lamps 3 and 5 are turned on with the end of the counting operation of the second timer section 49 (step S14).

Here, the rapid change of the surrounding illuminance from time T12 to time T16 is caused by the fact that the vehicle runs under the bridge,
This is a change that occurs when the vehicle passes through a shaded area such as below an elevated road.

As described above, according to the present embodiment, even if the surrounding illuminance becomes equal to or less than the second lighting illuminance L3 for lighting the headlamps 3 and 5, the lighting control unit 43 operates Only when the brightness continues until the count time of the second timer unit 49 has elapsed, the headlamps 3 and 5 are turned on with the end of the count operation of the second timer unit 49. If the vehicle passes through a shaded area such as under a bridge or an elevated road during daytime driving and the surrounding illuminance becomes dark for a time shorter than the count time of the second timer unit 49, the headlamps 3, 5
Can be prevented from being turned on, and the oncoming vehicle can be prevented from being overwhelmed.

If the count time of the first timer unit 47 has elapsed since the head lamps 3 and 5 were automatically turned off, the surrounding illuminance is changed to the second lighting illuminance at which the head lamps 3 and 5 should be turned on. Since the headlamps 3 and 5 are turned on as soon as the brightness becomes equal to or less than L3, the vehicle travels in a bright section for a time longer than the count time of the first timer unit 47 during the daytime driving, and then the tunnel. When the vehicle enters the inside, the head lamps 3 and 5 can be reliably turned on.

Therefore, in the daytime running, the surroundings are bright while the lighting and extinguishing of the headlamps 3 and 5 are prevented from being repeated frequently due to the illuminance fluctuation of a relatively short cycle generated when the vehicle passes under a bridge or the like. If the surroundings become dark after passing through a tunnel or the like after the state has continued for a relatively long time, the headlamps 3 and 5 can be quickly turned on.

In the present embodiment, the second lighting illuminance L3
And the second light-off illuminance L4 are set to different values, but may be set to the same value.

[0046]

As described above, according to the first and third aspects of the present invention, even if the surrounding illuminance is lower than the predetermined lighting illuminance for lighting the headlamp, the brightness is maintained at a predetermined level. Only when the vehicle continues for a long time, the headlamps are turned on. Therefore, when driving in the daytime, the vehicle passes through a shaded area such as under a bridge or under an elevated road, and the surrounding illuminance becomes the second level.
In the case where the time becomes darker for a time shorter than the count time of the timer section, the headlamp can be prevented from being turned on, and the oncoming vehicle can be prevented from being annoyed.

According to the second aspect of the present invention, when the first predetermined time, which is the count time of the first timer section, has elapsed since the headlamp was turned off, the surrounding illuminance decreases. Since the headlamp is turned on immediately when the brightness becomes lower than the predetermined lighting illuminance at which the lamp should be turned on, the vehicle travels in a bright section for a longer time than the count time of the first timer unit during daytime driving. After that, when the vehicle enters the tunnel, the headlamp can be reliably turned on.

Therefore, in the daytime running, the headlights are prevented from being repeatedly turned on and off due to a relatively short cycle of illuminance fluctuation that occurs when the vehicle passes under a bridge or the like. After a long time, if the surroundings become dark due to passing through a tunnel or the like, the head lamp can be quickly turned on.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a truth table of a flip-flop provided in the headlamp control device of FIG. 1;

3A is a diagram illustrating a relationship between a twilight detection signal of a twilight detection unit provided in the headlamp control device of FIG. 1 and ambient illuminance, and FIG. 3B is a diagram illustrating the head of FIG. It is a figure showing the relation between the night detection signal of the night detection part provided in the lamp control device, and the surrounding illuminance.

FIG. 4 is a diagram illustrating a configuration of a delay processing unit provided in the headlamp control device of FIG. 1;

FIG. 5 is a flowchart relating to control of a headlamp of a central processing unit provided in the headlamp control device of FIG. 1;

FIG. 6 is a flowchart relating to control of a headlamp of a central processing unit provided in the headlamp control device of FIG. 1;

FIG. 7 is a timing chart showing how the headlamp control device of FIG. 1 controls lighting and extinguishing of a headlamp and a tail lamp in response to a change in ambient illuminance.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Head lamp control device 3, 5 Head lamp 25 Photodiode 29 Central control unit 43 Lighting control unit 45 Lighting control unit

Claims (3)

[Claims] 1. An illuminance detecting means for detecting an illuminance around a vehicle, a switching means for turning on and off a headlamp, and the detected illuminance turns on the headlamp based on the detected illuminance detected by the illuminance detecting means. Only when the state where the lighting illuminance is lower than the predetermined lighting illuminance to be performed continues for a predetermined time,
Control means for giving an instruction to turn on the headlamp to the switching means. 2. The control unit includes a lighting control unit and a light-off control unit that gives an instruction to turn on and off a headlamp to the switching unit based on the detected illuminance detected by the illuminance detection unit. The lighting control unit is configured to receive a command to turn off the headlamp from the light-off control unit to the switching unit, and start a first predetermined time counting operation with the headlamp being turned off. A timer section, a second timer section that starts a counting operation for a second predetermined time as the detected illuminance becomes equal to or less than the predetermined lighting illuminance, and when the detected illuminance becomes equal to or less than the predetermined lighting illuminance, It is determined whether or not the count operation of the first timer unit has been completed. If the count operation of the first timer unit has been completed, the switch While the instruction to turn on the headlamp is given to the switching means, if the count operation of the first timer section is not completed, the detected illuminance is maintained while the count operation of the second timer section is continued. The headlamp according to claim 1, further comprising: a lighting instruction unit that gives an instruction to turn on the headlamp to the switching means only when the state where the illumination illuminance is equal to or less than the predetermined lighting illuminance continues. Control device. 3. An illuminance around the vehicle is detected by illuminance detecting means, and when the detected illuminance is lower than a predetermined lighting illuminance at which the headlamp should be lit, a switching means for turning on and off the headlamp is controlled. A headlamp control method in which a headlamp is turned on, wherein only when a state in which the detected illuminance detected by the illuminance detecting means is equal to or less than the predetermined lighting illuminance continues for a predetermined time, the switching means passes through the switching means. A headlamp control method, wherein the headlamp is turned on.