Abstract: An apparatus that is useful for acquiring and conveying a sheet includes a plenum having an opening for coupling a vacuum source to the plenum, a slide plate having a stop member positioned proximate a drop box opening in the slide plate, and a drop box adapted to slide within the drop box opening until a portion of the drop box engages the stop member so that the drop box is slidably installed in the slide plate. The apparatus may be used in an electrostatographic printing machine to improve top sheet acquisition.

Abstract: A sheet feeder assembly for acquiring and conveying a sheet comprises a plenum connectable to a vacuum source and having an opening facing the sheet to be conveyed, and a slide plate covering the opening. The slide plate has an acquisition surface facing the sheet to be conveyed and defining a plurality of apertures in communication with the plenum. A drive mechanism is connected to the slide plate and supported within the plenum, and is operable to translate the slide plate relative to the plenum to convey the sheet acquired thereby while maintaining the vacuum through the apertures. The drive mechanism includes a motor and eccentrically driven link connected to a carriage supporting the slide plate. The motor is coupled to a cam element that drives a flapper valve disposed between the plenum and a vacuum duct. The cam element also drives a height sensing arm supported to contact the top of the stack.

Abstract: A sheet separating and feeding system for separating a top sheet from a stack of sheets for sheet feeding, wherein a vacuum feed head has a two dimensional array of multiple vacuum tubes for vacuum engaging the top sheet, and a control system whereby at least a portion of the multiple vacuum tubes are variably positionally controlled relative to the top sheet to engage the top sheet at different levels in a different plane than the external surfaces of the other vacuum tubes so as to provide a variable three dimensional sheet corrugation inducing surface with the multiple vacuum tubes that is variable for different sheet properties.