PUBLIC TOILET CISTERN WATER SAVING DEVICE

The utility model discloses a public toilet cistern water saving device, which is composed of an electromagnetic valve which is arranged on the water inlet pipe of the cistern, and the controlling end of the public toilet cistern water saving device is directly connected with the wire of the street lamp. The street lamp is off in the daytime, the valve is fully open, and the cistern flushes the water one time each 5 minutes; the street lamp is on at night, the valve is closed incompletely, and the quantity of the supply water which flows into the cistern is decreased, which causes the cistern to flush the water one time each half an hour. So the number of the times of the water-flushing is reduced when a few persons or nobody uses the public toilet at night, which causes each cistern to save the water about 3000 ton each year.