Verarbeitungsmaschine für Pappe mit Vakuumtransportsystem

摘要

A paperboard processing machine (10) is disclosed for printing and otherwise processing sheets of paperboard (12), such as corrugated container blanks, and in which the sheets are conveyed from one section of the machine to another section by one or more vacuum transfer systems (16). Each vacuum transfer system (16) comprises an enclosure which is closed by a closure plate (40) for creating a subatmospheric pressure, which pressure forces the sheets into frictional engagement with the reaches of a plurality of conveyor belts (34) whereby the sheets are transported without contact of the opposite side of the sheet not contacted by the conveyor reach. In one embodiment the closure plate (40) is imperforate, while in the second embodiment the closure plate is provided with a limited number of apertures for providing a secondary flow of air upwardly against the bottom surfaces of the paperboard sheets. In addition, in one preferred embodiment, a plurality of slots are provided in the closure plate (40) for reducing the inflow of air at the entrance and exit ends (45) of the transfer section.