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:
Mar. 18, 1986
Filed:
Aug. 15, 1983
Jack Beery, Fremont, CA (US);
Frederick A Donahue, Walworth, NY (US);
Ronald E Shaul, Canandaigua, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
A sheet detector having an emitter (lamp), detector (phototransistor), operational amplifier and an RC network. As contamination is deposited on the emitter or detector, a feedback loop provides more drive to the lamp providing sufficient drive to hold the emitter of the phototransistor at its desired stage. As a first copy paper is passed between the emitter and detector, the RC network of a common mode operational amplifier detects a change and generates an output. As a subsequent sheet enters the system, the transmissibility abruptly changes again causing the common mode operational amplifier to provide a subsequent pulse indicating the presence of a multiple feed.