Developer powder supply in magnet brush development

摘要

A developer powder supply means is disposed within a developer reservoir for supplying developer powder to a magnet brush developing roller which is placed adjacently to a drum surface carrying an electrostatic latent image formed thereon. The developer powder supply means comprises a stationary sleeve and a rotatable cylindrical magnet enclosed by the stationary sleeve. The rotatable cylindrical magnet includes a magnet shunt means or has an odd number of magnetic poles to produce distorted distribution of the magnetic field. The stationary sleeve has an extended portion which is placed above the rotatable cylindrical magnet, where the magnetic field established by the rotatable cylindrical magnet does not effect the developer powder.