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. 28, 1993
Filed:
Aug. 21, 1992
Douglas T Rabjohns, Fairport, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
An apparatus in which a stack of sheets is detected at a preselected location. An air jet is directed towards an edge of the stack of sheets at a preselected location. A pressure transducer is located at the prescribed location and positioned to have the air jet at impact thereon. The pressure transducer is enabled to transmit a signal indicative of the absence of the stack of sheets at the preselected location in response to the air jet impacting thereon. The pressure transducer is inhibited from transmitting the signal in response to the stack of sheets blocking the air jet. When the stack of sheets blocks the air jet, the signal from the pressure transducer indicates the presence of the stack of sheets at the preselected location. A pneumatic stack height detector of this type may be used to regulate the movement of a stack of sheets used in electrophotographic printing machines.