| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent a lot of transfer paper to which fixing has not been performed well from being output by rapidly detecting abnormality in the midst of printing in a power supply using PWM control, especially, a power supply for an electromagnetic induction heating fixing device. <P>SOLUTION: In constitution where a PWM generation circuit 20 controls pulse width of a driving signal for driving switch elements 103 and 104 so that temperature of a fixing belt 92 conforms to a target value, a CPU 10 compares pulse width information from the PWM generation circuit 20 with maximum pulse width. When the determined pulse width is equal to maximum pulse width and a state where a detection value Is of a power supply 100 is equal to or under a predetermined value is continued for a predetermined time, the CPU 10 determines it as abnormality of the power supply 100, and stops the apparatus. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
