JPH0613273B2 - Automatic light control device for vehicle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic light control device for a vehicle, which automatically controls turning on / off of a light according to the illuminance outside the vehicle, and particularly to turning off the light. It relates to measures for setting timing.

(Prior Art) Conventionally, as an automatic light control device for a vehicle of this type, an illuminance sensor including a light receiving element or the like for detecting illuminance outside the vehicle is disclosed, for example, in Japanese Patent Laid-Open No. 55-140620. It is provided to judge whether the detected illuminance is below a predetermined threshold value, and turn on the vehicle light when the detected illuminance is lower than the threshold value, and turn off the light when the detected illuminance is higher than the threshold value. The ones that have been done are well known.

(Problems to be solved by the invention) By the way, in this conventional device, since the turning on / off of the light is controlled according to the illuminance detected by the illuminance sensor, for example, when the vehicle exits the tunnel, the light is immediately turned off. It is possible. However, at dawn when the illuminance gradually becomes bright, the speed across the threshold is slow, so the illuminance may change above and below the threshold,
There has been a problem that a so-called hunting phenomenon occurs due to repeated turning on and off of the light.

The present invention has been made in view of the above points, and an object of the present invention is to set two types of threshold values, which are reference values for turning on / off a light, to two types of threshold values. By deciding the timing of turning off the light by comparing with the detected illuminance, the light can be turned off quickly when the vehicle exits the tunnel, and at the same time, the light can be reliably turned off while preventing the hunting phenomenon at dawn. Especially.

(Means for Solving Problems) In order to achieve this object, the solution means of the present invention is, as shown in FIG. 1, an illuminance sensor 1 for detecting an illuminance H outside the vehicle and the illuminance as described above. The vehicle exterior illuminance H detected by the illuminance sensor 1 in response to the output of the sensor 1 is a predetermined threshold value K ₁
It is premised on an automatic light control device for a vehicle, which includes a control means 9 for turning on the light 2 when it is darker and turning off the light 2 when it is brighter.

Then, with respect to the automatic light control device, in the control unit 9, the threshold value K ₁ as the first threshold, the first threshold value K is lower than ₂ second threshold K ₂ is set, and the light 2 is turned off when the detected illuminance H of the illuminance sensor 1 remains for a predetermined time T ₂ or more between the two threshold values K ₁ and K ₁ .

(Operation) With this configuration, in the present invention, when the vehicle escapes from the tunnel, the illuminance H of the light detected by the illuminance sensor 1 rapidly rises above the first threshold value K ₁ .
The light 2 is turned off quickly because it is judged that the tunnel has escaped.

On the other hand, at dawn when the brightness becomes gradually brighter, the rise of the detected illuminance H to the first threshold value K ₁ or more is delayed, but the detected illuminance H is set to the first and second threshold values K ₁ and K _2. If there is, the light 2 is forcibly turned off by the control means 9. In this way, it is possible to quickly turn off the light 2 when exiting the tunnel and surely turn off the light 2 without hunting at dawn.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings starting from FIG.

FIG. 2 shows the overall configuration of an embodiment in which the present invention is applied to an automobile. Reference numeral 1 denotes an illuminance sensor including a light receiving element for detecting an illuminance H outside the automobile. The illuminance sensor 1 is not shown. For example, it is mounted so as to be directed upward from a mounting base arranged on a dash panel in the front of the vehicle compartment so that light from above passing through the front windshield is incident.

On the other hand, 2 is a headlight that illuminates the front of the vehicle. The headlight 2 is composed of a high beam lamp 3 for traveling, which illuminates the front of the vehicle body to a distance, and a low beam lamp 4 for passing, which illuminates the same range. The beam lamps 3 and 4 are provided with a changeover switch 5 for switching the lighting of the beam lamps 3 and 4 and a turn-on / off control relay 1
It is connected to the battery power source via the relay switch 10a of 0. 6 is a keyless switch that is turned on when a key of an ignition key switch (not shown) is inserted into the key cylinder, 7 is a switch that is turned on when executing auto light control, and 8 is the headlight 2 It is a light switch that is manually operated to turn on and off. Then, the illuminance sensors 1 and 3
The switches 6 to 8 serve as control means for controlling the turning on and off of the headlight 2 and are connected to the microcomputer 9
When the control signal is output from the microcomputer 9, the control relay 10 is operated to turn on the headlight 2.

The procedure of the signal processing performed by the microcomputer 9 will be described with reference to FIG. 3. First, in the first step S ₁ after the start, the illuminance H outside the vehicle detected by the illuminance sensor 1 is input, and the following Step S ₂
Then, it is determined whether the illuminance H is brighter (higher) than the predetermined first threshold value K ₁ . This judgment is Y>H> K ₁ .
If it is S, it is considered that the vehicle has come out of the tunnel, etc., and the step is continued until the predetermined first timer time T ₁ (for example, T ₁ = 0.3 seconds) has elapsed in step S _3. Repeat S _{2, S 3,} after the timer time _{T 1,} turns off the headlights 2 proceeds to step _{S 4.}

On the other hand, when the determination in step S ₂ is NO, that is, H ≦ K ₁ , in step S ₅ , the illuminance H and the second threshold value K ₂ lower than the first threshold value K ₁ are detected. When the determination is NO in H ≦ K ₂ , the process proceeds to step S ₇ and the headlight 2 is turned on.

Further, when it is determined that YES in H> _{K 2} in step _{S 5,} the first timer period proceeds to step _{S 6} T
_A second timer time T ₂ longer than ₁ (eg T ₂ = 3
Until seconds) elapses Repeat steps _{S 2, S 5, S 6} , after the timer time _{T 2,} turns off the headlights 2 shifts to step _{S 4.}

Therefore, in the present embodiment, as shown in FIG. 4, the headlight 2 is turned on when the illuminance H outside the vehicle detected by the illuminance sensor 1 is darker than the first threshold value K ₁ by the control procedure as described above. Turn it on, turn it off when it is bright,
It is configured to turn off the headlight 2 when the detected illuminance H remains between the first threshold value K ₁ and the second threshold value K ₂ lower than the _first threshold value K ₂ for a predetermined time T ₂ or more. ing.

Therefore, in the above embodiment, the keyless switch 6, the light switch 8 and the auto switch 7 are all turned off.
When N is operated, the illuminance H detected by the illuminance sensor 1 is compared in the microcomputer 9 with two types of threshold values K ₁ and K ₂ of large and small, and the headlight 2 is turned on / off based on the result. Controlled. When the vehicle exits the tunnel, the illuminance H input to the illuminance sensor 1 becomes brighter than the higher first threshold value K ₁ , as indicated by the chain double-dashed line in FIG. after passing of the threshold _{K 1,} a first timer time _T 1 (0.3
The headlight is turned off after the elapse of (seconds), which allows the headlight 2 to be quickly turned off when exiting the tunnel.

Further, at dawn when it becomes bright gradually, as shown by the solid line in the figure, when the detected illuminance H is darker than the first threshold value K ₁ but brighter than the second threshold value K ₂ , That is, as long as the illuminance H is between the thresholds K ₁ and K ₂ , the second timer time T is reached after the second threshold K ₂ of the illuminance H has passed.
_The headlight 2 is turned off when ₂ (3 seconds) has elapsed. In this case, the so-called dead zone of the illuminance H is between the two threshold values k ₁ and K ₂ , and the dead zone prevents the headlight 2 from hunting in the lighting state or the non-lighting state. Can be turned off.

In addition, in the above-mentioned embodiment, the case where it is applied to the automobile is shown, but it goes without saying that the present invention can be applied to other vehicles.

(Effects of the Invention) As described above, according to the present invention, the automatic light control device for automatically turning off the light when the illuminance outside the vehicle is brighter than a predetermined threshold value,
By setting another threshold lower than the above threshold and forcibly turning off the light when the detected illuminance stays between both thresholds for a predetermined time or more,
While realizing the quick turn-off of the light when the vehicle exits the tunnel, the light turn-off timing can be delayed at dawn to prevent the hunting phenomenon of turning on / off the light and to turn off the light with certainty. The accuracy of the turn-off control can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing the configuration of the present invention. 2 to 4 show an embodiment of the present invention, FIG. 2 is an overall configuration diagram of an automatic light control device, FIG. 3 is a flow chart diagram showing a signal processing procedure performed by a microcomputer, and FIG. FIG. 6 is a characteristic diagram showing a temporal change characteristic of illuminance at the time of exiting a tunnel and at dawn. 1 ... illuminance sensor, 2: headlight, 9 ... microcomputer, H ... illuminance, K 1 _... first threshold, K 2 _... second threshold.

Claims (1)

[Claims] 1. An illuminance sensor for detecting illuminance outside the vehicle and an output of the illuminance sensor, and when the illuminance outside the vehicle detected by the illuminance sensor is darker than a predetermined first threshold value, the light is turned on. An automatic light control device for a vehicle, the control means turning off the light when it is bright, wherein the control means has a second threshold value lower than the first threshold value, and An automatic light control device for a vehicle, wherein the light is turned off when the detected illuminance of the illuminance sensor stays between the two threshold values for a predetermined time or more.