| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus for securing safety by surely stopping energization to a heater during abnormal high temperature occurrence of the fixing heater. <P>SOLUTION: A sheet to which a developer is transferred by using a fixing roller heated with a radiation heater 8 is heated and fixed. When a temperature detection circuit 10 detects a prescribed abnormal high temperature when a heater temperature control unit lock 32 controls a direct current power source supplied from a boosting chopper circuit 7 to the radiation heater 8, on the basis of a detection temperature by the temperature detection circuit 10 of the fixing roller of a fixing part; a high temperature sensing circuit 12 stops supply of the direct current power source from the boosting chopper circuit 7 to the radiation heater 8 by generating an abnormal stop signal. Thus, in a fixing heater activator 1, when detecting the abnormal high temperature, drive of the radiation heater 8 is stopped in a hardware, and even during malfunction and erroneous detection, occurrence of a fire or the like is prevented to secure safety. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
