Patent ID: 9563166
Date: 2017-02-07
CPC Classifications: G03G

Claim:
1. A drum supporting structure adapted to a cleaning device formed as a unit including a photosensitive drum and a cleaning portion both mounted to a housing, the drum supporting structure rotatably supporting the photosensitive drum, which is connected to a shaft joint member that is connected to a drive shaft through which drive power is transmitted, the cleaning portion being configured to contact a surface of the photosensitive drum and remove residual toner on the surface of the photosensitive drum, the drum supporting structure comprising: a cylindrical flange disposed on the photosensitive drum and configured to be fitted into and connected to the shaft joint member; and a bearing disposed in the housing and configured to rotatably support the flange, the bearing including an inner circumferential surface fitted on the flange in a state where there is a gap between the inner circumferential surface and an outer circumferential surface of the flange, the inner circumferential surface including two planes, a long arc surface and a short arc surface, the two planes being separate from each other in a circumferential direction of the inner circumferential surface, the long arc surface and the short arc surface each connecting the two planes in the circumferential direction, the long arc surface being longer than the short arc surface in the circumferential direction, the bearing supporting the flange in a state where the outer circumferential surface of the flange is contacted with the two planes by a two-point contact due to a composite load which is a combination of a plurality of loads from a plurality of directions applied from the cleaning portion and a peripheral device to the photosensitive drum, such that the flange is rotatable, the two planes, sandwiching the short arc surface, being line-symmetric with respect to a direction in which the composite load is applied.