Abstract: A magnetic brush developer for use in electrophotographic copiers or the like, the developer comprising a magnet support shaft fixedly mounted with respect to the copier; a hollow, cylindrical magnet fixedly mounted on the support shaft; a hollow cylinder rotatably, concentrically mounted about the cylindrical magnet, the cylinder having at least one side, the one side including an annular support member for the cylinder where the support member is rotatably mounted on the magnet support shaft and projects inside of the cylinder to thereby provide a compact arrangement for the developer.

Abstract: A magnetic brush developing device including a plurality of developing rollers each consisting of a cylindrical stationary magnet and a cylindrical sleeve rotating around said magnet, said plurality of developing rollers being disposed among the surface of a latent image forming member, wherein said cylindrical stationary magnets each have (a) a developing magnetic pole positioned in a portion facing the surface of latent image forming member, (b) a transporting magnetic pole positioned rearwardly of said developing magnetic pole in the travelling direction of a developing agent and having an opposite polarity to that of the developing magnetic pole, and (c) an auxility transporting magnetic pole positioned in a portion facing the preceding developing roller in the travelling direction of developing agent and having a polarity identical with the polarity of said transporting magnetic pole, said developing magnetic poles having the identical polarity and thus delivery and receipt of the developing agent betwee

Abstract: A magnetic brush type developing mechanism is electronic copying machine characterized in that each of the developing rolls having a cylindrical multipole fixed magnet is provided with a magnetized pole or poles in other part than the developing region.