| 摘要 |
PROBLEM TO BE SOLVED: To provide a fixing device which can protect from damage due to a runaway power supply without interposing software and minimize the cost increase. SOLUTION: The fixing device includes: a first control unit that compares a detection signal obtained by a first temperature detecting means with a first reference signal and controls a first shut-off means 505a based on the comparison output; a second control unit that compares a detection signal obtained by the second temperature detecting means with a second reference signal and controls a second shut-off means 505b based on the comparison output; a third control unit that compares a detection signal obtained by a third temperature detecting means with a third reference signal and controls a first bidirectional three-terminal thyristor 502a based on the comparison output; and a fourth control unit that compares the detection signal obtained by the third temperature detecting means with a third reference signal or a fourth reference signal and controls a second bidirectional three-terminal thyristor 502b based on the comparison output; wherein at the runaway power supply, the first and second shut-off means and the first and second bidirectional three-terminal thyristors can be controlled without interposing software. COPYRIGHT: (C)2009,JPO&INPIT |
