JPS60164895A - Dimmer for signal lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a dimmer for a signal light using a power control element with a control pole such as a triac.

(Conventional configuration and 1,000 problems) Conventional traffic signal lights did not have a brightness control function for day and night, and were lit at night with the same brightness as during the day. Originally,
The brightness required to accurately recognize traffic lights is sufficient during the day and even in the dark at night; conversely, if it is too bright, you may feel dazzled.
This causes eye fatigue and impairs recognition of objects under traffic lights.

(Object of the Invention) In view of the above-mentioned drawbacks of the conventional technology, the present invention eliminates eye fatigue and cognitive impairment by keeping the daytime brightness the same as the conventional one and lowering the nighttime brightness by several tens of degrees, thereby achieving an energy-saving effect. The purpose is to extend the life of lamps.

(Structure of the Invention) In order to achieve this object, the present invention uses an optical sensor whose resistance changes depending on the amount of light, a resistor, a capacitor, a triac, and a bidirectional trigger element, and uses the triac as a load. Connected in series to an AC power source, the capacitor is connected to the primary side terminal of the triac, the optical sensor and resistor are connected in parallel to the secondary side terminal of the triac, and connected to the previous year's capacitor. By connecting the bidirectional trigger element between the parallel circuit of the light sensor and the resistor, the connection point of the capacitor, and the gate terminal of the triac, the light sensor changes ambient brightness into a resistance change. , phase control the voltage applied to the load.

With this configuration, the brightness of the signal light at night can be lowered by several tens of degrees.

(Explanation of Examples) An embodiment of the present invention will be described below with reference to FIG.

In Figure 1, 1 is a triac, 2 is a bidirectional trigger element, 3 is a resistor, 4 is a light sensor, 5 is a resistor, 6 is a noise absorption capacitor, 7 is a capacitor, 8 and 9 are diodes, and 10 is a noise shield. 11 is a surge absorbing element, 12 is a load, and 13 is an AC power source. In this circuit, when the optical sensor 4 is sufficiently irradiated with light, the resistance of the optical sensor 4 is small, the charging speed of the capacitor 7 is fast, and the voltage is also high. Therefore, the breakover of the bidirectional trigger element is accelerated, the phase control angle is also small, and the load current is brought to a state close to 100 degrees. on the other hand,
When the evening comes and the light incident on the optical sensor 4 begins to decrease, the resistance of the optical sensor 4 gradually increases and the charging speed of the capacitor 7 slows down. As a result, the breakover time of the bidirectional trigger element 2 is delayed, the phase control angle is increased, and the load current is reduced. At night, the resistance of the optical sensor 4 becomes extremely large, and the charging current to the capacitor 7 flows through the resistor 3. Therefore, when the ambient illuminance falls below a certain value, it saturates at the phase control angle determined by the circuit, and the load current becomes constant.

In other words, the advantage of this embodiment is that, as shown in Figure 2, a signal light that is lit 100% during the day will gradually decrease in brightness as the ambient illuminance gradually decreases, and the illuminance will fall below the set value. In this case, it is necessary to maintain the condition several tens of times lower than during the daytime.

(Effects of the Invention) As described above, according to the present invention, the brightness of the signal light at night when no brightness is required is reduced in accordance with the ambient illuminance, thereby eliminating the glare of the signal light and extending the life of the lamp. It can be used for a long time and saves energy.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a dimmer according to an embodiment of the present invention, and FIG. 2 is a diagram showing the brightness of a signal light during the day and at night. 1...triac, 2...bidirectional trigger element,
3.5...Resistance, 6,7...Capacitor, 8.9
...Tiode, 10...Coil, 11...Surge absorber. (5) Fig. 1 1≧ , Fig. 2 - Individual Cape -

Claims (1)

[Claims] It consists of an optical sensor whose resistance value changes depending on the amount of light, a bidirectional three-terminal thyristor (hereinafter referred to as TRIAC), a bidirectional trigger element, a capacitor, and a resistor, and the capacitor is connected to the primary terminal of the TRIAC, and the A parallel circuit of the optical sensor and the resistor is connected between the capacitor and the secondary terminal of the triac, and the parallel circuit of the optical sensor and the resistor is connected between the connection point of the parallel circuit of the capacitor, the optical sensor, and the resistor, and the dart terminal of the triac. A dimmer for a signal light, characterized in that it functions to lower the brightness of a signal light at night by connecting a bidirectional trigger element.