A gas stream classifier has a gas stream classifying means for classifying a feed powder supplied from a feed supply nozzle, into at least a coarse powder fraction, a median powder fraction and a fine powder fraction by an inertia force acting on particles and a centrifugal force acting on a curved gas...http://www.google.com/patents/US6015648?utm_source=gb-gplus-sharePatent US6015648 - Gas stream classifier and process for producing toner
