Patent ID: 8909090

Claim:
A charging device for charging an object comprising: a corona charger including, a charging electrode and a grid electrode having a plurality of holes and arranged to an opening formed nearer to the object than the charging electrode; a cleaning brush configured to clean the grid electrode; a sheet-type shutter configured to open and close the opening of the corona charger; a screw configured to hold the cleaning brush and the shutter; and a drive source configured to drive both the cleaning brush and the shutter by rotating the screw in a longitudinal direction of the corona charger, wherein the drive source rotates the screw so that a moving speed of the shutter in opening direction to be faster than that in closing direction, and wherein the cleaning brush is swingably supported by centering around a swing shaft that is parallel to a width direction of the corona charger which is in the direction perpendicular to the moving direction of the cleaning brush; a first limiting unit configured to limit angle α, that is a movable angle of the cleaning brush from a position that the cleaning brush overlapping from the swing shaft to a perpendicular line of the grid electrode, to a position that the cleaning brush moving downstream in a closing direction of the shutter; and a second limiting unit configured to limit angle β, that is a movable angle of the cleaning brush from a position that the cleaning brush overlapping from the swing shaft to the perpendicular line of the grid electrode, to a position that the cleaning brush moving downstream in an opening direction of the shutter, wherein the angle α is wider than the angle β.