Electrophotographic apparatus

摘要

An electrophotographic apparatus capable of forming a high quality image by a contact type developing system using a photoconductive belt and a developing roller. The belt has a tubular configuration. A single friction roller is made of rubber and received in the tubular belt to drive it in a rotary motion. The friction roller has an outside diameter smaller than the inside diameter of the belt to provide the belt with a slack. The developing roller contacts the slack of the belt and, therefore, contacts the belt over a sufficient nip width.