Browse Prior Art Database

Original Publication Date: 1983-Jun-30
Included in the Prior Art Database: 2004-Apr-04

Publishing Venue

Xerox Disclosure Journal


A document sheet transport with a controlled normal force particularly suited for transporting original document sheets over the platen of a copier and driving them into alignment with a registration edge with a controlled intermittent driving (nudging) force and slippage. The document is driven by small elastomer frictional feeding surfaces or pads 1 which are mounted centrally of highly deformable curved springs 2 extending radially from a rotating (driven) wheel hub 3 provided with an adjustment of the mounting position of at least one end of each spring 2 to the hub 3 to control the normal force engagement of the elastomer pad 1 with the document sheet being fed. That is, the normal force is controlled by preloading of the springs 2 by a sliding contact at the end of each spring with the hub to vary the radius of curvature of the spring, and therefore vary the spring force with which the spring presses the elastomer into contact with the document being fed. Since the normal force is controlled by the metal spring rather than the elastomer, it is independent of elastomer aging and wear problems as compared to an all elastomer feed wheel. The hub 3 may be driven at an angle to the platen for corner registering the document against two orthogonal registration edge guides.