| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect variation in rotational speed of an endless moving member without using a common encoder. <P>SOLUTION: The drive control device is provided with a density sensor 37 (comprising a reflectivity detecting means) formed along an outer periphery surface of a bottom right roller 66 (or any other roller) along the direction of its periphery and detecting the reflectivity of a pattern 66a with different reflectivity according to its position in the periphery direction. When image formation is not carried out (when the endless moving member is rotated at a constant speed), the data of reflectivity detected by the density sensor 37 during one rotation of the bottom right roller 66 are acquired for every specified period and written to a memory. When the image formation is carried out, the data of reflectivity detected by the density sensor 37 is acquired for every specified period and the variation in the rotational speed of a transfer transportation belt 60 is detected by comparing the data with the data in the memory. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
