JPH0319195Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a lighting control device that provides lighting for a certain period of time based on the output of a sensor.

[Conventional technology]

2. Description of the Related Art Conventionally, there is a wall clock in which when you clap your hands at night, a sensor output lights up a lamp for a certain period of time to provide illumination. It uses CDS to power the sensor and the amplifier of this sensor output only at night.

[Problem that the invention attempts to solve]

In the above, when the lamp is turned on at night,
CDS may be sensitive to the light from this lamp. Therefore, the power supply to the amplifier is cut off and the lamp goes out, and then power is supplied to the amplifier again, and the output of the amplifier at this time becomes unstable and the lamp may be turned on again. This operation was repeated, causing the lamp to dim.

The present invention makes it possible to eliminate the influence of lighting of a lighting device and reduce current consumption.

[Means for solving problems]

This invention cuts off the power supply to the sensor and output generation circuit when the surroundings are bright, and stops the operation of the sensor and output generation circuit while the output for lighting the lighting device is being output from the output generation circuit. It was designed to be kept.

〔Example〕

In FIG. 1, a lamp 2, which is a lighting device for illuminating a dial and hands, is provided in the upper frame of a wall clock 1, and a window 3 is provided in the lower part.
A concave mirror 4 as shown in FIGS. 2 and 3 is provided within this window 3. An infrared sensor 5 is provided almost at the focal point of the concave mirror 4, and infrared rays within a certain range in the room are focused by the concave mirror 4 and then focused on the infrared sensor 5. When the amount of infrared rays changes within the above-mentioned certain range, for example by waving a hand, the lamp 2 is turned on for a certain period of time. However, since the detection by the infrared sensor 5 is performed only at night, it is controlled by a light sensor such as a CDS, and an example of the circuit configuration will be explained based on FIG. 4.

In the figure, 6 is a CDS, which is provided in a part of the frame of the wall clock 1. 7, 8, 9 are resistances, 10
is a gate circuit, and 11 and 12 are transistors. 13 is an amplifier and comparator that generates an output when the output of the infrared sensor 5 is above a specified level; 14 and 15 are one-shot pulse generation circuits; the output pulse width of the one-shot pulse generation circuit 15 is that of the one-shot pulse generation circuit 14; It is set slightly longer.

In the above configuration, when the surroundings are bright, CDS
The resistance value of resistor 6 is small, and the output of gate circuit 10 is held at "1" by the voltage divided with resistor 7, and transistor 11 is turned off. Therefore, power is not supplied to the infrared sensor 5, the amplifier and comparator 13, and the one-shot pulse generation circuits 14 and 15, and they are in an inactive state.

If the surrounding area becomes darker than the set level, the CDS
6 and resistor 7, the output of gate circuit 10 is inverted to "0", transistor 11 is turned on, and infrared sensor 5, amplifier and comparator 13, one-shot pulse generator 14,
15 is supplied with power and starts operating.

If you want to know the time late at night, the second
Wave your hand within the condensing range of the concave mirror 4 in FIG. Depending on the setting of the light collection range, it is possible to generate an output from the infrared sensor by waving your hands while lying down. When the output from this infrared sensor 5 exceeds a specified level, the amplifier and comparator 13
Output is generated from one-shot pulse generator 1.
4 and 15 are triggered. The pulse from the one-shot pulse generator 15 enables the one-shot pulse generator 14 to generate an output, and this pulse is supplied to the transistor 12 to light the lamp 2. On the other hand, the output of the gate circuit 10 is set to "0" by the pulse from the one-shot pulse generator 15.
The transistor 11 is held in the on state. In other words, by lighting lamp 2, CD6
Even if the infrared sensor 5 reacts, the operation of the infrared sensor 5, amplifier and comparator 13, and one-shot pulse generators 14 and 15 is maintained without being affected by this. Therefore, the lamp 2 is lit for a certain period of time determined by the output pulse width of the one-shot pulse generator 14, and the time can be read. After the pulse from the one-shot pulse generator 14 stops, the pulse from the one-shot pulse generator 15 stops a little later. This is to compensate for the delay in the response of lamp 2. Lamp 2 turns off with a slight delay after the pulse from the one-shot pulse generator 14 stops, and after this completely turns off, the infrared sensor 5. This is to release the operation retention of the amplifier, comparator 13, etc.

FIG. 5 shows another embodiment, in which 16 is an analog switch, 17 is an inverter, and the same numbers as in FIG. 4 indicate the same things.

In this example, by turning off the analog switch 16 using the output pulse of the one-shot pulse generator 15, the output of the inverter 17 is
It is held at "0" and the operations of the infrared sensor, amplifier, comparator 13, etc. are maintained.

In addition, to prevent the light from the lamp from affecting the CDS, use a mechanical or liquid crystal shutter.
It may be provided on the front of the CDS, and the shutter may be closed while the lamp is on.

Further, in the above example, an infrared sensor is used as the sensor, but the sensor is not limited to this, and for example, a sensor that is sensitive to a specific sound may be used.

Furthermore, the present invention is not limited to lighting control for watches, but can be applied to anything that uses some kind of sensor to illuminate for a certain period of time only when it is dark.

〔effect〕

According to the present invention, since the operation of the sensor and the output generation circuit is maintained while the lighting device is turned on, it is possible to eliminate the adverse effects caused by the lighting of the lighting device. For this reason, the detection element such as CDS that detects the ambient brightness and the lighting device may be placed close to each other, increasing the degree of freedom in the mounting position of both, and eliminating restrictions on exterior design or design. It becomes less. Moreover, when the surroundings are bright, power is not supplied to the sensor and the output generation circuit, so wasteful current consumption due to these can be eliminated, which has a great effect on extending the life of the battery.

[Brief explanation of the drawing]

Figure 1 is a front view showing an example of the use of the present invention in a wall clock, Figure 2 is a plan view showing the main parts of Figure 1 extracted and enlarged, and Figure 3 is the left side of Figure 2. figure,
FIG. 4 is an electric circuit diagram showing one example of the circuit configuration, and FIG. 5 is an electric circuit diagram showing another example of the circuit configuration. 2...Lighting device, 5...Infrared sensor, 6...
cds, 7...resistance, 10...gate circuit, 11...
...transistor, 13...amplifier and comparator, 14, 15...one shot pulse generator, 16...analog switch, 17...inverter.

Claims (1)

[Scope of utility model registration request] A sensor that is sensitive only to a specific object, an output generation circuit that generates an output for a certain period of time after the sensor is sensitive, a lighting device that lights up based on the output from this output generation circuit, and the surrounding area at a set level. A control circuit supplies power to the sensor and the output generation circuit only when it gets dark, and the sensor and the output generation circuit operate while the lighting device is lit by the output from the output generation circuit. A lighting control device consisting of a holding circuit that holds the.