The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 15, 1992
Filed:
Apr. 22, 1992
Leo A Beaudet, Milford, MA (US);
Robert O Kaplan, Milford, MA (US);
Other;
Abstract
An apparatus for charging insulating, nonmagnetic toner particles includes a semiconductive, elastomeric toner applicator roll in rolling contact with the dielectric or photoconductive drum which carries the electrostatic image to be developed. Toner is metered onto the surface of the toner roll and tribocharged, and the toner-bearing roll is rotated past a field electrode which repels airborne toner back to the toner applicator roll. A vacuum housing is placed in proximity to the field electrode to collect airborne toner. The field electrode is maintained at a direct current potential which is below the value required to cause corona discharges to the toner roll surface.