A developing device in which toner fed from a toner cartridge is caused to flow down by a toner supply roller and, then, mixed with a developer by an agitating roller unit which is made up of a spiral blade and a plurality of radial blades. The spiral blade of the roller unit is greater in outside diameter...http://www.google.es/patents/US4855783?utm_source=gb-gplus-sharePatente US4855783 - Agitating roller and restricting member for a developing device
Agitating roller and restricting member for a developing device
