PURPOSE: To shorten a time from the ON of a main switch up to copy enable status, i.e. a reload time, by sending a reload signal by a timer control signal or a temperature control signal on the basis of the temperature state of a fixing roll.

CONSTITUTION: A thermistor 3 detects the surface temperature of the fixing roll and a CPU 12 outputs a signal from a heater control output port (heater ON) to a heater driving SSR 8 through a buffer 19 and turns on/off the SSR 8 to control the fixing roll at a prescribed temperature. A fixing roll surface temperature T3 (a resistor value of the thermistor 3) to make a reload time t1 obtained from a reload timer (RAM) 13 almost coincide with a reload time t2 obtained from a temperature controller is selected. When the fixing roll surface temperature T at the ON of the main switch 7 satisfies T3<T, the reload signal is extracted from the temperature controller, and when T3>T, the reload signal is extracted from the reload timer 13.