| 摘要 |
PROBLEM TO BE SOLVED: To enable anyone to exchange parts used and to surely maintain the parts used by detecting the conductive state of a conductive state changing element and deciding that parts are new or old by a change in the output signal of the detection. SOLUTION: A use history presence detecting device 11 is in the conductive state, when a fixing device is not used. When a new fixing device 1 is incorporated in an image forming device and its power is supplied, the temp. of the heating roller of the fixing device rises by a heat source. Therefore, the use history presence detecting device 11 is changed into a nonconductive state by the rising of the temp. The conductive state of the detecting device 11 accompanying the rising of the temp. is detected by a control part 10 and a control circuit fixing device coefficient means provided on the main body side of the image forming device is reset with the output signal from the control part 10. After that, the fixing device coefficient means counts the number of sheets used by the image forming device or its energizing time. |
