Abstract: A copy sheet feeding system for use in a printing, copying, duplicating and like machine includes a conveyor board for moving copy sheets thereover in seriatim fashion. A vacuum chamber extends lengthwise of the conveyor board, with openings extending longitudinally of the conveyor board and communicating with the vacuum chamber. An access mechanism is movable relative to the vacuum chamber and openings to effectivly expose the openings progressively in the direction of movement of the copy sheets. This effectively provides a moving vacuum device which moves with the copy sheets as the sheets move over the conveyor board.

Abstract: A moisture system control apparatus is provided for metering the rate of feed of dampening fluid from a fountain apparatus including a fountain roller to a master on a master cylinder of a lithographic duplicating machine. The control apparatus comprises a linkage for converting continuous rotary input motion to incremental rotation of the fountain roller, and infinitely variable selector apparatus for adjusting the magnitude of the rotation increments employed during a first mode of operation which obtains while printing is in progress.