POWER CONTROLLER AND HEATER CONTROLLER AND IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To eliminate the malfunction of a zero cross signal even in countries or regions encountering the distorted voltage waveform of an AC power source; and to achieve an optimum on-off timing signal for a triac. SOLUTION: Current-carrying control to a ceramic heater 701 conducts on-off switching for the triac after a first delay time (approximately 2 ms) with reference to the rise edge (a point changing off to on) of the zero cross signal when a positive voltage is input from the AC power source 901. Meanwhile, the current-carrying control conducts the on-off switching for the triac after a second delay time (approximately 4 ms) with reference to the tailing edge (a point changing on to off) of the zero cross signal when a negative voltage is input from the AC power source 901. COPYRIGHT: (C)2006,JPO&NCIPI