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:
Nov. 17, 1998
Filed:
Jan. 13, 1997
Paul Hansen, Westminster, CA (US);
Sheldon F Raizes, Rancho Palos Verdes, CA (US);
Xerox Corporation, Stamford, CT (US);
Abstract
A single tray or multi tray sheet feed system is provided. A sensor is provided to sense the sheets leaving from the single tray or multi tray system. If the paper weight of sheets of paper on a tray fall within a first range of paper weight values, the sensor is designed to have a first given voltage response condition for sensing these sheets and if the paper weight of the sheets falls within a second range of paper weight values the sensor is designed to have a second given voltage response condition for sensing the latter sheets. A current value supplied to the emitter of the sensor can be controlled to provide the desired voltage response or a resistance in a phototransistor collector circuit can be varied to provide the desired voltage response condition. If the first range of paper weight values is lighter than the second range of paper weight values, the sensor, when in the first given voltage response condition, will have a voltage response, when sensing a sheet of a given paper weight, which is higher than the voltage response when the same sensor senses a sheet of the same paper weight, when the sensor is in the second given voltage response condition. A voltage response value sensed by the sensor of the first sheet fed from a tray is stored in memory as the voltage response value for all sheets on that particular tray. The voltage response value sensed by the same sensor of subsequent sheets fed from that particular tray is compared with the voltage response value in memory to detect a multi sheet feed from the tray.