FRICTION RETARD FEEDER RETRACTING RATCHET
Original Publication Date: 1992-Oct-31
Included in the Prior Art Database: 2004-Apr-06
Xerox Disclosure Journal
Some friction retard feeders operate by raising and lowering continually rotating feed rolls into contact with copy sheet stacks. In the auxiliary feeder of such machines, lowering the feed head also releases a ratchet mechanism which allows springs below the paper tray to raise the stack to contact a feed roll. The purpose of the ratchet is to interrupt the upward motion of the stack so that it does not follow the feed roll when it rises away from the stack. This mechanism is added to the feeder design in order to avoid stream feeding of sheets. Unfortunately, the ratchet mechanism involves several parts and an unacceptable tolerance management problem, and general operation implies contact with the paper stack without the feed roll coming in contact with the retard pad both while the roll is raised and lowered.