Abstract: A matrix printing apparatus of the type having a path for sequentially transporting a series of documents to be printed between a plurality of dot matrix ballistic print heads and back-up platen rollers opposite each print head, the dot matrix ballistic print heads adapted, when actuated, to simultaneously impact an ink source and one side of each document as each document passes the print heads to apply printed material to each document in a pre-programmed array. The improvement of the present invention comprises moving the back-up platen rollers from a first position adjacent the print head when the print head is actuated, to a second position at a distance from the print head when the print head is not actuated.

Abstract: A new and improved vacuum document feeder provides a vacuum cup support mechanism which follows a somewhat crescent-shaped coupler curve that eliminated the vacuum cup wear-producing disadvantages of the prior art and provides for increased feeding rates. A four-bar system moves a table over the somewhat crescent-shaped coupler curve, while at all times holding an edge of the table parallel to the documents. At least one vacuum cup is pivotally mounted on the table, to sweep over an angle which accommodates leaning documents. Cams on a drive pulley associated with the transport system coordinates the table movement with both the pivoting and vacuumizing of the cups.