Patent ID: 8626029

Claim:
An image forming apparatus comprising: an image carrier configured to drivingly rotate by power generated by a driving source; and a power transmission system configured to transmit the power from the driving source to the image carrier, the power transmission system comprising a coupling member serving as a damper configured to attenuate oscillation, the coupling member comprising: a viscous fluid configured to provide a resistance against rotation of the image carrier, a male fitting having a recess formed by an inner circumferential surface of the male fitting and an inner bottom surface of the male fitting, a female fitting having an inner bottom surface, the male fitting and the female fitting being fitted with one another so that the inner bottom surface of the male fitting faces the inner bottom surface of the female fitting, a rotary shaft of the image carrier penetrating through the male fitting and the female fitting in a direction in which the male fitting and the female fitting are fitted with one another, a rotating resistor being configured to integrally rotate with the rotary shaft, the male fitting and the female fitting each being rotatable relative to the rotary shaft, and the rotating resistor being positioned together with the viscous fluid in the recess of the male fitting so that the rotating resistor is surrounded by the inner circumferential surface of the male fitting and so that the rotating resistor is bordered on opposite sides by the inner bottom surface of the male fitting and the inner bottom surface of the female fitting.