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:
Sep. 04, 1979
Filed:
Nov. 02, 1977
James L Bacon, Boulder, CO (US);
Larry M Ernst, Boulder, CO (US);
William G Hauptman, Boulder, CO (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A digitally regulated power supply for the corona charging unit of an electrostatic copying machine in which a sample of the ionic current of the corona unit is utilized in conjunction with a digital regulator to regulate the power supply establishing the charge of the corona. The digital regulator in conjunction with at least one pulse width modulated power supply permits very fast rise and fall times of the power supply current. Further, between duty cycles of the machine, the digital regulator stores a representation of the correct operating point of the corona charging unit determined in the immediately prior duty cycle. In the next duty cycle, the representation is utilized by the digital regulator to initially regulate the power supply.