| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a paper passing control method for a fixing device in which improvement of image forming efficiency and forced standby time for a user can be made unnecessary while surely solving fixing failure in image forming paper of a large size passing immediately after passing an image forming paper of a small size by speedily and efficiently making surface temperature of a heating roll in a shaft direction, which is made not uniform immediately after passing of the image forming paper of the small size, uniform. <P>SOLUTION: Two thermistors detecting the surface temperature in a central position in the shaft direction and a position on side end part of the heating roll are provided. When an image forming request for the A4 size, the large size is made immediately after the passing of the image forming paper of the small size, the paper passing direction of the image forming paper of the A4 size for the fixing device is made horizontal if the surface temperature of the heat roll in the shaft direction detected by each thermistor exceeds the permitted fixing temperature and at the same time variation occurs between the top limit fixing temperature and the bottom limit fixing temperature. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
