Inventors:
Bruce G. Johnson - Vancouver WA
Pete Gysling - New Plymouth ID
Assignee:
Hewlett-Packard Development Company, L.P - Houston TX
International Classification:
B65H 522
US Classification:
271 25, 271 315, 271 1002, 271 402
Abstract:
A media advance device includes a pick roller and a pair of sensors. The first sensor may be an encoder utilized to determine the speed of media advance. In addition, data from the first sensor and/or the second sensor may be utilized in a closed loop feedback system to alter the time in which an error signal may be returned according to the level of the media in the media tray. In addition, the speed of the media advance may be varied in real time to compensate for variations in the time intervals required to advance sheets of media from the media tray to the second sensor. By virtue of the detected speed of media advance as sensed by the first sensor and/or the second sensor, the level of media in the media tray may be calculated in a substantially accurate manner.