Abstract: A printing system for producing a print job, the printing system including a print engine for imaging regular substrates, fed to the print engine from a regular substrate feeding apparatus and delivering the imaged regular substrates to an output; and a duplexer operatively coupled to the print engine having a first path for feeding imaged regular substrates to the print engine for duplex printing, the duplexer having a second, sheet insertion, path for feeding special sheets to the output of imaged regular substrates.

Abstract: A printing system for producing a print job, the printing system including a print engine for imaging regular substrates, fed to the print engine from a regular substrate feeding apparatus and delivering the imaged regular substrates to an output; and a duplexer operatively coupled to the print engine having a first path for feeding imaged regular substrates to the print engine for duplex printing, the duplexer having a second, sheet insertion, path for feeding special sheets to the output of imaged regular substrates.

Abstract: In a dual engine printing system producing a multipage print job from first and second serially connected printing engines at a common output from the second engine, where the second printing engine has a duplex return path bypassing its printing path and extending substantially therethrough, a high productivity simplex job printing mode is provided in which alternate pages are substantially simultaneously printed in both the first and second printing engines, but the alternate pages printed in the first printing engine are fed to the second printing engine duplex return path to bypass the printing path of the second printing engine and then are automatically interleaved in the common output with the alternate pages printed in the second printing engine. The duplex return path is preferably a bidirectional loop extending above the printing path and driven in a reverse sheet feeding direction for this simplex printing.

Abstract: An improved sheet stacking apparatus for stacking a wide variety of sheets, especially small sheets, using a rotatable disk stacking unit that receives each sheet in slots defined by fingers on the disks and rotates to invert the sheets. Closely adjacent fixed axis corrugating frictional drive rollers engage the trail edge area of the sheet by the rotation of variable radius disks to larger radius areas thereof which interdigitate with these fixed drive rollers, so that the trail edges of sheets being inverted by the disk contact and are driven by the corrugating rollers. The periphery of the frictional drive rollers is inside of the maximum radius of the disk stacking unit and outside of its minimum radius, so as to be only intermittently interdigitated therewith.

Abstract: A trail edge transport belt is provided over the elevator platform which receives sheets from a disk stacker. The trail edge transport belt engages and ensures the proper inversion of sheets moved by the rotating disk regardless of the size and weight of the sheet. To ensure that long, light weight sheets do not collapse on themselves prior to inverting, the trail edge transport belt is rotated at a velocity which is greater than the velocity which the sheets are fed to the disk and/or is arranged at an angle to the elevator platform so that a distance between the transport belt and the elevator platform decreases as the transport belt extends away from the rotatable disk.

Abstract: An apparatus in which a plurality of developer rollers develop a latent image recorded on a flexible photoconductive member. The photoconductive belt is deflected by the developer material to wrap around at least a portion of the first two developer rollers forming wrapped development zones. The last developer roller may either have the photoconductive belt wrapped about a portion thereof, or the photoconductive belt may remain in an undeflected condition. The developer rollers having the photoconductive belt wrapped thereabout rotate in opposite directions. A blanket of developer material is formed between the last two developer rollers. An apparatus of this type optimizes development of the latent image recorded on the photoconductive member.