| 摘要 |
PROBLEM TO BE SOLVED: To reduce the fluctuation of a power source in every half cycle of a commercial power source by controlling energizing amount to plural heat generating means in every half cycle of the commercial power source, setting fixed control power by putting plural half cycles in a lump and controlling the calorific value of the heat generating means based on the set control power. SOLUTION: In a zero cross detection circuit 802, a zero cross detection range is set to several volts above and below the zero cross part of the voltage of the commercial power source, and a zero cross signal is outputted in accordance with the detected range. A CPU 105a calculates the energizing amount of heaters 119A and 119B according to temperature information detected by a temperature sensor 5. Then, the triacs 801A and 801B of a fuser control part 3 are on/off controlled by an SSR 804A and 804B according to heater control signals 810A and 810B from the CPU 105a. When the heater control signals (810A and 810B) are at a high level, a current energizing the heater (119A and 119B) is applied. |
