Abstract: A vacuum corrugation feeder used to feed a wide variety of sheet sizes and stocks includes a variable ratio feedhead plenum. Included within vacuum plenum is an adjustable shutter apparatus that includes a foam roller mounted for rotation on shaft. A shutter member in the form of a plastic sheet is connected to the foam roller and can be wrapped and unwrapped around the foam roller by rotation of knob that is connected to the shaft depending on whether the vacuum pressure is to be high or low. The foam roller is mounted above a plenum plate of the vacuum plenum such that rotation of the knob in a clockwise direction causes the shutter to unwrap from the foam roller and partially cover vacuum holes in the plenum plate and thereby decrease the amount of negative pressure from the vacuum plenum that reaches sheets being fed.

Abstract: A smart paper tray determines paper size to enable maximization of throughput. The width and length of paper in the paper tray is determined by detectors mounted on slides contacting edges of the paper. The detectors can be linear or rotary encoders, potentiometers, etc. The detectors provide signals to a pitch controller and/or instructor. The pitch controller controls pitch of the printing apparatus on the basis of the signals such that the pitch is maximized to enable maximum throughput of the printing apparatus. The instructor instructs an operator on the basis of the signals how to load the paper to achieve maximum throughput.

Abstract: Document sheet handling apparatus for a copier for sequentially feeding document sheets on to and off of the copying platen with a document feeder frictionally engaging a document sheet inserted at a first side of the platen and transporting a document sheet over the platen by continued engagement, and a flexible platen cover integrally connecting to the document feeder for movement therewith over the platen, and a reel system, including a retracting spring for reeling up the flexible platen cover into a scroll adjacent the first side of the platen and above the document sheet input, so that a document sheet may be fed under the scroll, the flexible platen cover being unreeled to extend over the platen by the movement of the integral document feeder to overly the platen and provide an opague and light reflective platen cover, and a releasable latch adjacent the opposite side of the platen for latching the document feeder and the flexible platen cover over the platen in a position for copying the document, and