Patent ID: 7684735
Filing Date: 2010-03-23
Classification: G03G

Abstract:
1. A charging apparatus which is to be incorporated into an image forming apparatus having a photoreceptor drum, for forming an image by an electrophotographic method, comprising: a corona electrode having a pointed projection section with pointed projections for charging a surface of the photoreceptor drum by applying a voltage to the surface through corona discharge and having a coating layer containing a material different from the electrode material of which the corona electrode is formed, the coating layer being provided only on the tips of the pointed projections; a first power supply for applying a voltage to the corona electrode; a shield case provided around the corona electrode at an interval from the same to cover at least part of the periphery of the corona electrode excluding the region of a gap between the corona electrode and the photoreceptor drum; a grid electrode provided between the photoreceptor drum and the corona electrode; and a second power supply for applying a voltage to the grid electrode.