| 摘要 |
PURPOSE:To accurately judge the abnormal heat generation of a heater element to interrupt the supply of electric power. CONSTITUTION:This thermal fixing device for an image forming device, is provided with the heater element 4 generating heat by making current flow, a current detecting circuit 5 detecting the value of the current flowing in the heating element 4, a voltage detecting circuit 6 detecting the value of a voltage applied to the heating element 4, a multiplier 7 calculating the electric power supplied to the heating element 4 from the current value outputted from the current detecting circuit 5 and the voltage value outputted from the voltage detecting circuit 6, an integrator 8 interrupting a path for supplying electric power to the heater element 4 when supply electric power to the heating element 4 in a specified time, exceeds a supply electric power set in advance, from the result of the calculation of the multiplier 7, a time-type initializing circuit 9, a comparator 10, and an interrupting circuit 2. |
