Patent ID: 7263299
Filing Date: 2007-08-28
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a photosensitive unit; a static eliminator unit which eliminates static electricity from a surface of the photosensitive unit; a charging unit which charges the surface of the photosensitive unit subjected to the static elimination by the static eliminator unit; an exposure unit which exposes the surface of the photosensitive unit charged by the charging unit; a developing unit which develops the surface of the photosensitive unit exposed by the exposure unit; a potential sensor which detects a residual potential of the surface of the photosensitive unit subjected to the static elimination by the static eliminator unit, a charging potential of the surface of the photosensitive unit charged by the charging unit, and an exposure potential of the surface of the photosensitive unit exposed by the exposure unit; detection means for detecting a difference between the charging potential detected by the potential sensor and the residual potential detected by the potential sensor; and judgment means for judging a lifetime of the photosensitive unit in accordance with the difference detected by the detection means.