The heating roller which possesses the abnormal detection mannered null heating unit of the fixation device

摘要

PROBLEM TO BE SOLVED: To provide a fixing device capable of detecting various troubles related to the temperature control of a heating roller, and preventing accidents, such as firing.;SOLUTION: This fixing device 37 is provided with the heating roller 37A, a heater driver 240, and a thermistor 37H. The heating roller 37A has heaters 37C, 37D and heats a recording paper sheet. The heater driver 240 drives the heaters 37C, 37D. The thermistor 37H detects a surface temperature of the heating roller 37A. According to this constitution, the heater driver 240 is stopped, when the surface temperature of the heating roller 37A exceeds a prescribed value; the surface temperature of the heating roller 37A is detects thereafter for a prescribed time by the thermistor 37H; and the first abnormality is informed when the surface temperature of the heating roller 37A does not go down during a predetermined time.;COPYRIGHT: (C)2009,JPO&INPIT