PURPOSE: To reduce power consumption by supplying an output current yielded with generation of a solar cell when daytime is detected to ventilation means, while supplying an output current of an ordinary power supply to the ventilation means when the detection is executed after sunset.
CONSTITUTION: In a ventilation system including a plurality of ventilation fans 4 for ventilation of a living room and a toilet in a housing, a first switch 6 connected to a solar cell 2 is brought into an automated operation mode during sunshine, and when with this situation, a sunshine/sunset detection circuit 5 detects the time of sunshine based upon a current from the solar cell 2, a relay 8 is switched to the side of a solar cell input. Hereby, the current from the solar cell 2 is supplied to the ventilation fans 4 after passage through the relay 8 and a second switch 9 altered to the automated operation mode for operation of the same. Further, when the current from the solar cell 2 is stopped and the sunshine/sunset detection circuit 5 detects midnight time, the relay 8 is changed over to the side of midnight time whereby the ventilation fan 4 is operated with an ordinary power supply 3.
KISE KAZUHIKO
SUZUKI TAKESHI
| JP61200532B |