| 摘要 |
<P>PROBLEM TO BE SOLVED: To quickly perform power block at the primary side of a power supply even if there occurs any abnormality such as a power supply earth fault. <P>SOLUTION: An abnormality detection circuit 27 is constituted in such a manner that a reference resistor 31 and a posistor 33 which operates so as to raise the resistance value of the reference resistor as an atmospheric temperature rises are connected in series between the power supply 29 and the earth. When abnormal power generation occurs in a fixing roller 39, the posistor 33 raises the resistance value, and accompanied by this, the potential of a connecting point 35 rises. Accordingly even if any abnormality such as the power supply earth failure occurs, the power block at the primary side of the power supply can be quickly performed. <P>COPYRIGHT: (C)2008,JPO&INPIT |
