PURPOSE: To prevent heating of an opening/closing control solenoid of the fluctuation prize-winning device, and also, to miniaturize the solenoid by opening an opening/closing piece by a sufficient voltage current at the time of starting opening, and continuing the opening of the opening/closing piece by a small current after releasing the opening/closing piece, at the time of applying a power supply voltage to the opening/closing control solenoid.

CONSTITUTION: When an opening signal of a fluctuation prize-winning device is outputted to an A signal being an output of an interface 13, a second switching transistor 35 conducts, a C signal which becomes an input of a second diode 37 is boosted to, for instance, 12 volts, and a voltage of a second power source 62 is applied to an opening/closing control solenoid 50 through a second diode 37. Also, a pulse generator 41 outputs a signal of an H level by several hundred milliseconds from the time of output of the opening signal, a first switching transistor 25 conducts and a B signal being an output is boosted to, for instance, 30 volts, and a voltage of a first power source 61 is applied to the opening/closing control solenoid 50 through a first diode 27.