Charging device

摘要

In a corona charger including a housing that encloses a discharge electrode and has an open portion on a charging-object side and a shutter that opens and closes the open portion, if discharge products dropped from ends of the shutter adhere to a photosensitive member and absorbs moisture, an image defect called “image deletion” may occur. A charging device includes a corona charger including a discharge electrode and shields provided on two respective sides of the discharge electrode. The corona charger has an open portion on a charging-object side thereof. The open portion is opened and closed by a sheet-type shutter in a longitudinal direction of the charger. The sheet-type shutter is curled in a transverse direction such that a central portion bulges, with respect to two ends, in a thickness direction of the shutter from a front surface that is nearer to the discharge electrode toward a back surface.

主权项

1. A charging device that charges a photosensitive member, the charging device comprising:
a corona charger including a discharge electrode that discharges electricity when a voltage is applied, shields that are provided on two respective sides of the discharge electrode, and an open portion that is provided nearer to the photosensitive member than the discharge electrode is; a sheet-type shutter movable for opening and closing the open portion; a fixed member fixed to a leading end of the shutter that is on a downstream side in a direction in which the shutter moves when the shutter is closed; and a moving mechanism that holds the fixed member and moves the shutter in a longitudinal direction of the corona charger, wherein at least a portion of the shutter in the longitudinal direction excluding the leading end to which the fixed member is fixed is curled in a transverse direction of the shutter such that a central portion bulges, with respect to two ends, in a thickness direction of the shutter from a front surface that is nearer to the discharge electrode toward a back surface that is farther from the discharge electrode.