Patent ID: 8463159

Claim:
An image forming unit, comprising: a rotatable photoconductor; an elastically deformable charging roller for charging the photoconductor, which roller contacts with an outer face of the photoconductor and rotates following rotation of the photoconductor; a regulating member for regulating movement of the charging roller, which member is placed so as to surround the charging roller, the regulating member having a pressing section which contacts with the charging roller in a longitudinal direction of the charging roller to press the charging roller against the photoconductor during one-way rotation of the photoconductor and the charging roller; and a control section for controlling return of the charging roller to a free state out of contact with the pressing section, wherein the pressing section is inclined with respect to a direction of a line connecting a center of a cross-sectional circle of the charging roller to an axis of the photoconductor, as seen from an axial direction of the photoconductor in a state that the charging roller contacts with the pressing section, the pressing section is inclined farther away from the photoconductor toward an upstream of the one-way rotation of the photoconductor, and the charging roller, when pressed by the pressing section against the photoconductor during the one-way rotation of the photoconductor and the charging roller, assumes a generally elliptical shape in cross-section.