Automatic document feeding method and apparatus and duplexing document scanning device using same

摘要

A method and apparatus for picking the top or the bottom sheet, as desired from a stack of sheets of documents to be scanned using opposed rollers or other members which apply differing amounts of frictional force to opposite faces of the sheet to be picked. The opposed rollers each have substantially the same coefficient of friction and are selectively rotated each in the same direction of rotation but with different torques to apply differential frictional forces to pick the desired sheet from the top or the bottom of the stack.