JPS6357256B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flashing control device for automobile lamps that automatically controls turning on and off of lamps (head lamps, marker lamps, tail lamps, etc.) of two-wheeled or four-wheeled automobiles.

An example of the circuit configuration of a conventional blinking control device is shown in FIG. In FIG. 1, 1 is a brightness (illuminance) sensor, 2 is an illuminance-voltage conversion circuit, 3 is a small lighting level comparator that compares the output of this conversion circuit 2 with the small (tail) lighting level, and 4 is the conversion circuit. A head lighting level comparator compares the output of circuit 2 with the head lighting level, 5 is a small (tail) drive circuit, and 6 is a headlamp drive circuit.

That is, the output of the brightness sensor 1 that detects illuminance is converted into a voltage signal, and this voltage and each comparator 3, 4 are
The small (tail) drive circuit 5 and the headlamp drive circuit 6 are operated by comparing the current level with the reference level.

However, with this configuration, each lighting level relies only on the illuminance level of a single brightness sensor, so when the output levels of the comparator and sensor are close to each other, such as at dusk, it is difficult to When passing a guard, etc., the lamp turns on, and the hysteresis characteristic of the comparator (each comparator has hysteresis to prevent frequent repetition of turning on and off) keeps the light on even after passing the guard. will be done. In other words, even though the brightness is such that it is not necessary to turn on the headlights, a problem arises in that the vehicle must drive with the headlights on.

To avoid such problems, (1) reduce the hysteresis of the comparator, (2) lower the lighting level, (3) install a delay circuit between the comparator and the drive circuit, and place it in the shade of a tree, etc. Sometimes a method is used to prevent it from working, but
In either case, problems occur due to changes in various environmental conditions.

For example, in the case of item (1), the hysteresis is small, so if you are in the shade of a tree at dusk, the light will turn on,
The lights turn off after passing, which solves the problem of driving with the lights on, but the lights repeatedly turn on and off each time the vehicle is shaded by a tree or guard, creating a sense of discomfort for oncoming vehicles.

In the case of item (2), even if the lamp no longer malfunctions in the shade of a tree, the situation is even more dangerous as it will not turn on even when the surroundings are dark.

In the case of item (3), it is effective for shade trees, guards, etc. that can be passed through in a short time, but for items that exceed the delay time, the result is similar to the situation in item (1). In addition, when entering a tunnel during the day, the lighting timing is delayed, which not only increases the danger especially when driving at high speeds, but also makes it impossible to meet the legal requirements for automatic control, so this part is a manual control method as a means of dealing with tunnels. must be added, and the benefits of automatic control are lost.

The present invention has been made in consideration of the above points, and
We provide a flashing control device for automotive lights that can automatically control flashing to suit environmental conditions, such as not turning on when passing under a tree or guard at dusk, and turning on immediately when entering a tunnel during the day. The purpose is to

The present invention uses a plurality of illuminance sensors with different spectral characteristics such as red, green, and blue, and utilizes the differences in their characteristics to calculate changes in illuminance and hue due to environmental conditions when driving a car, using coefficients such as time and travel distance. This data is stored in advance as data, and this data is compared with signals from the plurality of illuminance sensors to perform lighting/extinguishing control in accordance with environmental conditions.

Hereinafter, the present invention will be explained in detail based on examples.

FIG. 2 shows an embodiment of the present invention.
A to 11C are brightness (illuminance) sensors that detect brightness, and 12A to 12C are these sensors 11A to 12C.
11C is a signal conversion circuit that converts the output into a voltage signal; 13 is an A/D converter that converts the output of each signal conversion circuit 12A to 12C from analog to digital (A/D);
A D converter, 14 is a microcomputer that receives the signal after A/D conversion, performs necessary processing and creates a control signal, 15 is a small (tail) drive circuit, and 16 is a headlamp drive circuit, both drive circuits. 15 and 16 are the microcomputer 14
It operates by receiving control signals from.

The sensors 11A to 11C are sensitive to red, green, and blue wavelength regions, as shown in FIG. 5, for example. That is, the sensor 11A has a blue (B) spectral characteristic, the sensor 11B has a green (G) spectral characteristic, and the sensor 11C has a red (R) spectral characteristic.

Note that the brightness sensor may include light outside visible light as shown by the dotted line in FIG.

FIG. 3 shows an example of the configuration of the sensors 11A to 11C and their output signal conversion circuits 12A to 12C. When detecting the front of a tunnel of illumination, a convex lens 23 is used to condense the light, as shown in FIG. 4a, or a parabolic mirror 24 is used as shown in FIG. 4b. Further, the conversion circuit 12 includes amplifiers 31 and 32, resistors 33 and 34, a variable resistor 35 for adjusting the degree of amplification, and the like.

Next, the operation will be described. When the vehicle is running, the surrounding brightness is detected by sensors 11A to 11C. As shown in FIG. 5, the sensors 11A to 11C have spectral characteristics that are sensitive to multiple wavelength regions of red, green, and blue.
Color and illuminance judgments are made based on the output.
Furthermore, the change in the spectral characteristics of sunlight between day and night is the result of a difference in the attenuation characteristics of RGB, as shown in FIG. Moreover, the difference in the output changes of the sensors 11A to 11C is most noticeable at dusk and dawn.

The output characteristics shown in FIG. 6 are expressed in a simulated manner as shown in FIG. 7. For example, each sensor 11A to 11
When the output voltage ratio (illuminance level ratio) of C reaches the state of t ₁ (R′:G′:B′), the small (tail) lamp is turned on and the state of t ₂ (R″:G″: B″)
If the condition is set so that the headlamp turns on when the
By calculating the 1C output voltage ratio as a coefficient of time or travel distance, it is possible to accurately determine whether the illuminance has decreased at dusk or dawn, or because of the influence of the shade of a tree or a guard. This judgment is made by the microcomputer 14. It is assumed that the computer 14 stores in advance necessary data (data regarding the form of changes in illuminance level due to environmental conditions, etc.).

For example, when it approaches dusk, each sensor 11A-1
When the 1C output begins to decrease and the vehicle passes through the shade of a tree or a guard, the pattern shown in FIG. 8 is as shown in FIG. The outputs of the sensors 11A to 11C change simultaneously as at point A. This change is different from the level difference described in FIG. 7, and it can be easily determined that the illuminance has decreased due to the influence of the shade of a tree or a guard. Therefore, unnecessary lighting is prevented.

Further, by setting the output voltage level (point L) of the sensor shown in FIG. 8 at various levels, the following control form becomes possible.

For example, if level L is the small (tail) lamp lighting level, a slightly longer delay is set, and if the headlamp lighting level is set, a shorter delay is set, and when the illuminance becomes even lower, to ensure safety visibility. The shortest delay time is set, and a computer calculates so that the light is turned on at each time (the delay time may be a delay distance). As a result, the lamp does not turn on in the shade of a tree without a certain level of output level L or time t, but turns on immediately in a dark tunnel with no illumination. The basis for determining the immediate lighting is that in the case of a very dark tunnel, the output decreases in a sharp pattern as shown in FIG.

In addition, since RGB sensors are used, by memorizing the output level conditions specific to sodium lamps, mercury lamps, etc., it is possible to detect tunnels immediately before entering and to judge night lighting. .

For example, when outputs such as those shown in FIGS. 10a and 10b are obtained during the daytime, it is determined that the tunnel is illuminated with sodium lamps, and the lamp is turned on.

Although the spectral characteristics of the sensor are obtained by arranging an optical filter in the above embodiment, if the sensor itself has spectral sensitivity characteristics, the optical filter becomes unnecessary. Further, the number of sensors is arbitrary as long as there is a plurality of them. Furthermore, it is also possible to replace the A/D converter with a comparator or the like.

In the above explanation, we talked about the lighting level, but
The turn-off level is set, for example, between t1 _{and t2} after the headlamp is turned on at time _t2 (the time when the headlamp is turned on) in FIG. In addition, if t is long in the condition shown in Figure 8, and the headlamp is on when passing through the dark, then B
If the respective lighting levels shown in FIG. 7 are not reached at the point, the light is turned off.

As described above, according to the present invention, multiple sensors with spectral characteristics such as RGB are used to determine color and illuminance level, and the differences in these characteristics are used to determine whether illuminance is decreasing due to time of day, shaded by trees, or guarded. The system automatically controls the flashing to suit the environmental conditions, such as turning off the light when passing under a tree or passing a guard at dusk, or turning it on immediately when entering a tunnel during the day. This can contribute to safe driving.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional example of a flashing control device for an automobile lamp, Fig. 2 is a block diagram showing an embodiment of the present invention, and Fig. 3 is a configuration of a sensor section and a signal conversion circuit in the same embodiment. A circuit showing an example, FIGS. 4a and 4b are configuration explanatory diagrams of the condensing means of the sensor section, FIG. 5 is a spectral characteristic diagram of the sensor, FIG. 6 is a diagram showing the relationship between time and amplifier output, and FIG. The figure is number 6
A pattern that simulates the figure, Figure 8 is a pattern when passing through the shade of trees, guards, etc. at dusk.
FIG. 9 shows a pattern when entering an unilluminated tunnel, and FIGS. 10a and 10b show spectral characteristics when a tunnel illuminated with sodium lamps is detected. 11A~11C...Brightness sensor, 12A~
12C...signal conversion circuit, 13A...A/D converter, 14...microcomputer, 15...small (tail) drive circuit, 16...headlamp drive circuit.

Claims (1)

[Claims] 1 Multiple illuminance sensors with different spectral characteristics such as red, green, and blue, and changes in illuminance and hue due to environmental conditions when driving a car are stored in advance as data that is used as coefficients for time, mileage, etc., and this data is and means for generating a control signal by comparing the signals from the plurality of illuminance sensors.