Charging device, toner-image forming unit, and image forming apparatus

A charging device comprising:

• a housing having a U-shaped cross-section, disposed such that an opening thereof faces a surface of a rotating image carrier, and extending in an axial direction of the image carrier;
• a discharge electrode configured to charge the surface, the discharge electrode being attached to the housing, inside the housing, and extending in the axial direction;
• a grid electrode that has a plate-like shape and is disposed across the opening of the housing to face the surface of the rotating image carrier;
• and
• a cleaner having a protrusion that comes into contact with a bottom plate of the housing and configured to move in the axial direction to clean the discharge electrode in a state in which the protrusion is in contact with the bottom plate, regardless of whether the opening in the housing faces upward or downward, wherein:
• the cleaner further includes a brush that comes into contact with and cleans the grid electrode when the cleaner cleans the discharge electrode in a state in which the protrusion is in contact with the bottom plate of the housing, and
• the protrusion is a plurality of physically separate protrusions provided in lines along a depth direction of the charging device.