PURPOSE: To prevent outputted image quality from being deteriorated by providing a roller body, a driving means which dividedly drives the roller body and a combining means combined with the driving means for transferring the driving operation from the driving means to the roller body in an axis direction.

CONSTITUTION: The roller body 1 is rotated and driven by the driving operation transmitted from the gear 3 through the joint 5 in the axis direction. Therefore, strength which affects the pressurizing condition of the roller body 1 on an image carrier 2 is absorbed and relaxed by the joint 5 and only a torque is transmitted from the gear 3 to the roller body 1, which is rotated and driven. Even if the center of the axis of the roller body 1 doesn't meet the center of the gear 3, the joint 5 transmits the driving operation of the gear 3 to the roller body 1 so that the angular velocity of the driving operation is not practically changed and the rotating peripheral velocity of the roller body 1 is constantly kept at a prescribed definite speed. Hereby, the outputted image quality is prevented from being deteriorated due to unevenness in transferring, cleaning, contact electrification, etc.