Patent ID: 7000627

Claim:
A safety valve for a toilet tank, comprising: a solenoid operated valve in a water supply pipe to a toilet tank, which is biased toward a closed position in which the flow of water through the pipe is cut off, but moves to an open position, allowing water to flow through the pipe, when electricity flows through the solenoid; a valve switch that closes an electric circuit supplying electricity to the solenoid when a toilet is flushed, causing the solenoid operated valve to open and allowing water to flow through the pipe to refill the toilet tank; a float mechanism in the toilet tank that rises as the tank refills, and causes a float switch to open the electric circuit when the water in the tank reaches a certain level, cutting off the supply of electricity to the solenoid, causing the valve to close and cut off the flow of water to the tank; and a timing mechanism that causes a timer switch to open the electric circuit after a set period of time, when the float mechanism does not do so, thus preventing water from overflowing the tank, even if the float mechanism fails.