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. 20, 2002
Filed:
Aug. 30, 2000
Victor Tung, Vancouver, WA (US);
Pierre Joseph Kaiser, Vancouver, WA (US);
Matthew A. Shepherd, Vancouver, WA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An embodiment of a media movement apparatus is used to detect an edge of a unit of media in a media path in an inkjet printer using an optical sensor. When the inkjet printer is operating in a mode in which units of media are continuously moved into the media path, a mechanical sensor will not reliably allow detection of the leading edge of a unit of media. Determining the location of the leading edge of the unit of media is done to correctly place an image on the unit of the media. After ejecting the previous unit of the media into an output tray, the current unit of the media is moved backward in the media path while measuring the output of an optical sensor. If the edge is detected while moving backward, the current unit of the media is moved to the input side of a print zone. If the edge is not detected and the optical sensor indicates the presence of media, a media jam is indicated. If the edge is not detected and the optical sensor indicates the absence of media, the current unit of the media is moved forward while measuring the output of the optical sensor to detect the edge. If the edge is detected, then the current unit of the media is moved forward a predetermined distance. Next, the current unit of the media is moved backward in the media path while measuring the output of the optical sensor.