Method and device capable of gathering small water flow into large water yield and outpouring large water yield once for flushing toilet

The invention discloses a method and device capable of gathering small water flow into large water yield and outpouring the large water yield once for washing a toilet. According to the invention, a small water flow slowly flows into a water tank, the water tank is supported on a support, the water tank can rotate around a support point, and the water tank is designed into an asymmetric structure by taking the support point as a reference; the notch edge of the water tank is in a horizontal status when the water level in the water tank is level with the support point; and the gravity center of the water tank quickly deviates to the front end of the support point (the front end is a water outlet end of the water tank) after the water level in the water tank exceeds the support point, so that the water in the water tank outpours out of the front end of the notch of the water tank to flush the toilet. By adoption of the method and device provided by the invention, the small water flow can be gathered into large