Patent ID: 7983591

Claim:
An image forming apparatus, comprising: an image carrier that carries an electrostatic latent image; a toner carrier roller that is provided, on a surface thereof, with a plurality of convex sections and a concave section which surrounds the convex sections, is shaped approximately like a cylinder, is arranged opposed to the image carrier, and rotates while carrying a toner layer of charged toner on the surface thereof; a bias applier that applies a developing bias voltage to the toner carrier roller; a housing that collects the toner carried on the surface of the toner carrier roller at a place downstream to an opposed position facing the image carrier in a rotation direction of the toner carrier roller; a seal member that is interposed between the toner carrier roller and the housing, and abuts on the surface of the toner carrier roller to prevent leakage of toner from the housing; a controller that is adapted to perform a toner removal operation which removes toner adherent to the seal member by rotating the toner carrier roller while the toner carrier roller abuts on the seal member, in a condition that at least a part of respective surfaces of the convex sections do not carry toner so as to be exposed; and a restrictor that abuts on the surface of the toner carrier roller at a place upstream to the opposed position facing the image carrier in the rotation direction of the toner carrier roller to restrict a thickness of the toner layer carried on the surface of the toner carrier roller, and removes toner on the convex sections when the toner removal operation is performed, wherein the controller is adapted to provide, in performing the toner removal operation, an electric potential difference between the toner carrier roller and the restrictor so that a polarity of a direct current potential of the restrictor relative to the toner carrier roller is the same as that of the charged toner.