Patent ID: 6208825
Filing Date: 2001-03-27
Classification: G03G

Abstract:
A low-friction single component development apparatus for developing electrostatic latent images on an image bearing surface, the low-friction single component development apparatus comprising:(a) a sump containing a supply of developer material particles;(b) a moveable donor member assembly including a donor member for transporting developer material particles from said sump through a development zone adjacent the image bearing surface, said donor assembly including a series of isolated electrodes protruding above said donor member;(c) a first combination of AC and DC biases for charging said supply of developer material particles in said sump resulting in charged developer material particles having a desired polarity and charge distribution;(d) a second combination of AC and DC biases for providing fringe electric fields for depositing particles of said charged developer material particles onto said donor member;(e) means for forming a cloud of said charged developer material particles on said donor member, within the development zone, for image development; and(f) an electrostatic filtering zone located upstream of the development zone relative to movement of said moveable donor assembly for electrostatically removing wrong-sign charged developer material particles from said donor member, thereby controlling and maintaining said desired polarity and charge distribution of said developer material particles within said sump.