Developing device for developing charge images on a charge image carrier

US4460266A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Walter Kopp · Taufkirchen, DE
• Karl-Heinz Saalmuller · Munich, DE

Key dates

• Filing date: Apr 19, 1982
• Grant date: Jul 17, 1984
• Expiry date: Apr 19, 2002

Classification

• Technology area (CPC G): Physics
• CPC primary: G03G15/0921
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

In a developer station for an electrophotographic printing or copying machine, there is provided a developer drum apparatus for producing optimum inking density and resolution of the charge images being passed through the developer station on a charge image carrier. The apparatus comprises a rotating hollow cylinder within which is contained a stationary magnet arrangement in the form of a series of rows of permanent magnets, each row being disposed longitudinally with the cylinder, supported on a stator carrier. The first row of magnets is disposed adjacent the lower end of the cylinder for attracting developer mix particles from the floor of the developer station housing and the succeeding rows of magnets are disposed along the transport path of particles on the cylinder to promote transport of the mix upwardly on the cylinder to an inking gap area with the charge image carrier. A final row of relatively wider magnets is disposed at the upper end of the cylinder with its longitudinal centerline substantially offset from the inking gap to promote uniform distribution of the mix along the length of the cylinder just prior to inking. The layer amount of developer mix carried by the …