| 摘要 |
PURPOSE:To prevent the deform of a sheet material support, to ensure synchronous rotation of the support and a photosensitive body, and to prevent color shear due to defective synchronous rotation by providing plural torque transmitting devices that engage with the support near both ends of the cylindrical sheetlike material support. CONSTITUTION:The first and second transfer gears 531, 534 that engage with a photosensitive drum and the first and second transmission gears 532, 533 are fixed on a transmission shaft. Usually, when two gears are engaged by reference pitch circles with each other, a tooth of the gear 532a enters between two teeth of the gear 531. However, a gap called backlash shown by (b) in the figure is generated, and even when the gear 531 rotates in the direction of the arrow A, the gear 532a does not rotate synchronously. Accordingly, the gear 532a is made to rotate synchronously with the gear 531 by eliminating backlash by fixing a gear 532b of the same shape with the gear 532a at a position shown by dotted lines in the figure. As transmission gears 532, 533 are fixed firmly to the transmission shaft 535, a lag of synchronism in the transmission shaft 535 does not occur. |
