Patent · US Expired

Magnetic brush apparatus for developing electrostatic images

US4638759A · kind A · utility

6Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1985
Grant dateJan 27, 1987
Priority date
Expiry dateJun 17, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0921
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A magnetic brush apparatus for use in electrographic copiers and the like for applying magnetic developer to electrostatic images at a development zone to effect development of such images. Such apparatus includes a non-magnetic sleeve having a rotatably driven magnetic roller therein, and magnetic shunt means for selectively reducing the magnetic field produced by the magnetic roller outside the sleeve. By reducing the magnetic field shortly after the developer first contacts the image and maintaining the reduced field until the developed image is advanced beyond the influence of the magnetic roller, a trailing edge development artifact is avoided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.