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:
Aug. 21, 1984
Filed:
Jun. 16, 1982
Applicant:
Inventors:
James R Champion, Longmont, CO (US);
Robert W Pries, Longmont, CO (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03G / ; G03G / ;
U.S. Cl.
CPC ...
355 / ; 355 / ; 355 / ; 118653 ; 118663 ; 118688 ; 118691 ; 430 30 ;
Abstract
A toner concentration control test cycle in which a developed test area is formed on a photoconductor charged to a dark charge level. The optical reflectivity of the developed test area is sensed and the result used to replenish toner if indicated. During the test cycle, the magnetic brush bias potential is altered to produce development of the test patch in the gray area with the level of dark charge held constant at a predetermined nominal level. An electrostatic probe and associated circuitry are provided to maintain dark charge at the nominal level during the test cycle.