| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce an out of color registration by bringing the cycles of angular velocity variations of respective photo-receptors in phase without increasing the size and cost of an apparatus. <P>SOLUTION: Four photo-receptors 1 are driven by independent motors 2. A drive shaft of each motor 2 is provided with a drive gear 11, and a drive shaft of the photoreceptor 1 is provided with a slave gear 10 with five ribs 13. Assuming that the interval between the photoreceptors is L, the diameter of the photoreceptor is D, and the number of the ribs k is 5, L ≈ n(πD/k). Since the rib parts 13 differs from each other in board thickness, the contraction amount immediately after molding is varied depending on the position where each rib 13 exists or not. As a result, the circular form of the slave gear undesirably becomes star-like, and the angular velocity variation of each photoreceptor 1 driven by the slave gear 10 has a cycle interlocked with the rib positions. Therefore, the cycles of the angular velocity variation of each photo-sensor 3 can be synchronized with each other by arranging a photo-sensor 3, and detecting rib positions, and thereby making the position of each rib 13 coincide with each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
