| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an image forming apparatus controlled based on smoothness of a recording medium and capable of preventing a fixing failure.SOLUTION: An optical detector 50 determines a fixing set temperature Th of a fixing device 60 according to the established smoothness at a time T3, transmits a heat supply quantity for realizing the determined fixing set temperature Th to a heat source control circuit of the fixing device 60 from a control part, and changes the fixing set temperature in a nip part. When it is difficult to change the fixing set temperature for each one sheet of a recording medium, the control part calculates an average value of the smoothness of each recording medium, and sets also the recording medium having the smoothness whose calculated average value is equal to or less than a predetermined value to a fixing set temperature not causing a fixing failure. When the smoothness deviated from the predetermined value more than the average value of the smoothness is detected, the control part determines that an unexpected abnormal operation such as being unable to normally detect the smoothness due to a conveyance failure is generated when changing the set fixing temperature according to the smoothness of the recording medium.</p> |
