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:
Dec. 26, 2000
Filed:
Jan. 08, 1999
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method and apparatus for measuring a dimension of an object which utilizes a reflective photosensor and a facing reflective surface, wherein the spacing between the sensor and the reflective surface is varied depending on the dimension to be measured. The preferred application of the invention is in a sheet feeder for a printer wherein the invention provides an electrical signal indicative of the size of sheets in the sheet feeder. The electrical signal may be used to control a printing function. The sheet feeder (10) includes a base (14) having a paper guide (18) slideably mounted thereon. The guide (18) carries a tapered arm (26) which includes a reflective surface (28). A reflective photosensor (30) is fixedly mounted on the base opposite the reflective surface (28) such that the variable distance between the sensor (30) and the surface (28) as the paper guide (18) is adjusted gives a correspondingly variable electrical output from the sensor. When the sensor (30) is adjusted against the edge of a stack of sheets, the sensor's output represents a dimension of those sheets.