| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress the occurrence of degradation of printed image quality due to the sag and tension of a recording medium. <P>SOLUTION: An image forming apparatus includes image forming means 107, medium conveyance means 105, fixing means 25, sag detection means 112 detecting the presence or absence of the sag of the recording medium between the medium conveyance means and the fixing means, and control means 104 and 109 changing medium conveyance speed by the medium conveyance means and/or the fixing means, based on the detection result of the sag detection means, to make a difference in speed between the medium conveyance speed of the medium conveyance means and the medium conveyance speed of the fixing means. The control means changes the medium conveyance speed so that the difference between the speed before the medium conveyance speed is changed and the speed after the medium conveyance speed is changed is a first value, for the period from when the switching of presence or absence of the sag is detected to when the medium conveyance speed difference exceeds a threshold and changes the medium conveyance speed so that the difference between the speed before the medium conveyance speed is changed and the speed after the medium conveyance speed is changed is a second value smaller than the first value, for the period from when the medium conveyance speed difference exceeds the threshold to when the switching of presence or absence of the sag by the sag detection means is detected again. <P>COPYRIGHT: (C)2012,JPO&INPIT |
