| 摘要 |
A fixing device for reducing, without fail, the heating output without using a control circuit if an excessive temperature rise of a rotary heating member is predicted, even if the control circuit fails or runs away. In the fixing device, heating of a fixing belt for heat-fixing an unfixed image on a recording medium is controlled by a body-side processor. When the fixing belt stops or rotates at a rotational speed equal to or below a threshold, an oscillation stop circuit stops the oscillation of an inverter circuit to stop the heating, independently of the processor. To check the operation of a rotation detection circuit for detecting the rotating state of the fixing belt (fixing roller) and the oscillation stop circuit, self-diagnosis is utilized to ascertain that the fixing belt is not heated by giving a heating instruction when the condition of not heating the fixing belt is satisfied is performed when the power is turned on or is performed regularly during standby. |
