Quick opening and closing device after power failure of valve

The utility model discloses a quick switching device after power loss of a valve, which comprises a connecting pipe, an electromagnetic valve is arranged on the outer side of the connecting pipe, and a switching mechanism is arranged on the outer side of the connecting pipe and positioned on the right side of the electromagnetic valve. According to the utility model, through the arrangement of the motor, the screw rod, the moving plate, the connecting rod, the blocking plate and the control box, a worker can block water flow in the connecting pipe when the electromagnetic valve is powered off, so that the situation that the water flow in the connecting pipe is not controlled when the electromagnetic valve is powered off and the control of a rear pipeline is influenced is avoided; and by arranging a warning lamp, a fixing plate, a rotating rod, a rotating disc and a rotating plate, whether the electromagnetic valve is in a power-losing state or not can be conveniently detected, a worker is reminded, the worker