Image forming device for forming a uniform toner layer on a developing roller

摘要

An image forming device which allows reducing a linear velocity ratio of a developing roller against a sensitive body, which enables a pole pitch of a magnetic field generating layer to be miniaturized, and which generates a uniform and adequately thick toner layer on the developing roller. A toner regulating element formed by a sheet metal material having elasticity and non-magnetic characteristics elastically contacts a surface of the developing roller. The developing roller has an elastic body layer and a magnetic field generating layer having a minute pole pitch. The toner regulating elements serves to regulate a thickness of the toner layer without vibration induced from the pole pitch of the magnetic field generating layer. Thus, the toner layer can be uniform and of an adequate thickness, and reducing the linear velocity ratio of the developing roller against the sensitive body does not generate any drawbacks.