Charging device and image forming apparatus

A charging device comprising:

• a discharge electrode that faces a surface of a rotatable image carrier and charges the surface of the image carrier, the discharge electrode having a substantially long shape extending in a direction in which a rotational axis of the image carrier extends;
• a case that extends in a longitudinal direction of the discharge electrode and encloses the discharge electrode, a side of the case nearest to the image carrier being open;
• a substantially plate-shaped grid electrode that is provided between the image carrier and the discharge electrode;
• a cleaning member that cleans at least one of the discharge electrode, the case, and the grid electrode by being guided along the case and moving in a longitudinal direction of the case;
• a regulating portion that is provided between the cleaning member and the case and regulates a distance between the cleaning member and the case in a direction orthogonal to the direction of movement of the cleaning member by coming into contact with one of the cleaning member and the case;
• and
• a supporting portion that supports the regulating portion and allows the regulating portion to move in a direction away from one of the cleaning member and the case with which the regulating portion is to come into contact.