| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which surely controls the start and the stop of supplying electric power to a heater for fixing based on timing in which amplitude is set to be zero even though there is some distortion in supplied AC electric power. <P>SOLUTION: A power source controlling part (70) controlling a power source part to supply the heater with AC electric power is provided with a zero cross detection circuit (71) to output a first zero cross signal (Z1) meaning the timing in which the amplitude of the AC electric power is set to be zero by detecting the timing, a CPU (72) to generate a pseudo zero cross signal (Zp) in timing that the zero cross detection circuit (71) has to output the first zero cross signal (Z1) by detecting the first zero cross signal (Z1), an OR circuit (73) to output the OR of the first zero cross signal (Z1) and the pseudo zero cross signal (Zp) as a second zero cross signal (Z2) and an AC output control circuit (74) to give a control signal (Sh) to the power source part based on the second zero cross signal (Z2). <P>COPYRIGHT: (C)2004,JPO |
