| US 7,588,245 B2 | ||
| Friction retard sheet feeder | ||
| Barry P. Mandel, Fairport, N.Y. (US); and Robert Alan Clark, Williamson, N.Y. (US) | ||
| Assigned to Xerox Corporation, Norwalk, Conn. (US) | ||
| Filed on Nov. 03, 2005, as Appl. No. 11/266,401. | ||
| Prior Publication US 2007/0096385 A1, May 03, 2007 | ||
| Int. Cl. B65H 3/52 (2006.01) | ||
| U.S. Cl. 271—122 [271/125; 271/262; 271/265.04] | 6 Claims |
| 1. An apparatus adapted to separate and advance media sheets from a stack of media sheets, comprising:
a media sheet advancing device including a drive roll and a retard roll wherein the drive roll and the retard roll include
a feed nip therebetween for driving the media sheets from a stack of media sheets in a feed tray at a velocity;
a first drive system to selectively drive the drive roll at a first velocity in a forward direction;
a second drive system to maintain the retard roll at a second velocity through a slip clutch having a torque when only one
sheet is in the feed nip;
a motion sensor for detecting when the retard roll stops rotating at the second velocity corresponding to when a plurality
of sheets are in the feed nip;
the second drive system selectively varies the second velocity of the retard roll when the plurality of sheets are in the
feed nip;
a control system varies the velocity of the retard drive system between the second velocity and a third velocity;
the second velocity is substantially zero;
the third velocity is in a reverse direction for sequentially feeding each bottommost sheet from the plurality of sheets back
into the feed tray until only one sheet is in the feed nip; and,
the control system returns the retard drive system from the third velocity to the second velocity after the more than one
sheet is removed from the feed nip.
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