JP2988663B

PURPOSE:To eliminate the need for special members and to inexpensively and easily impress a developing bias to a movable developer carrier which carries a thin layer of a one-component developer consisting of only the magnetic or nonmagnetic toner on the surface and carries the same by bringing a conductive member into sliding contact directly with the surface of the thin layer at the time of impressing the bias voltage to said carrier. CONSTITUTION:A cylindrical developing roller 11 which consists of a stainless steel, etc., and is formed to have electrical conductivity on at least the surface is disposed in the aperture of a developing container 16 which houses the one-component developer 15 prepd. by incorporating a carbon and charge control agent into polystyrene, polyester, styrene/allyl resin, etc. This roller is brought into contact with a photosensitive drum 17 on the outside of the container 16. The developing bias of the voltage higher than the ground potential of the drum 17 needs be impressed to the roller 11 and for this purpose, a conductive blade 12 consisting of phosphor bronze of about 0.2mm thickness and a lead wire 14 are simultaneously welded to a fixing member 13 provided to the container 16 and the tip of the blade 12 is brought into sliding contact with the roller 11. The negative potential of a DC power supply 18 is impressed to this part.