| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive driving device capable of reducing fluctuation of a rotating speed of a driven body by suppressing force to move a carrier of an epicycle reduction gear to the thrust direction.SOLUTION: In a driving device, a twisting direction and a rotating direction of each helical gear are set so that thrust moving force toward a driving motor 111 side is generated on a secondary sun gear 131 integrated with a first carrier 123 when the driving motor 111 is rotationally driven, and a projecting portion 136 of the secondary sun gear 131 is brought into contact with a second carrier 133 at a downstream side in the transmitting direction of the rotating driving force from the driving motor 111, by the thrust moving force of the second sun gear 131 integrated with the first carrier 123 at an upstream side. The driving device includes urging means for urging the first carrier 123 to a driving motor 111 side through a drum shaft 70, a joint 171 and an output shaft 138, by increasing a spring constant of a pressure spring 85 of positioning means for positioning a photosensitive drum 40 in the thrust direction. |
