ANORDNING FOR AVLEGGNING AV ARK I ARKBEARBETANDE MASKINER, SERSKILT ARKTRYCKMASKINER

摘要

A device for use in a sheet delivery mechanism for a printing press for forcibly seating a sheet on a delivery pile notwithstanding the cushion of air below the sheet. The device includes a pair of tube assemblies arranged parallel to one another above the delivery pile symmetrically on opposite sides of the delivery center line, with each tube assembly consisting of inner and outer tubes in snugly telescoped relation, air being supplied to the inner tubes under pressure. The tubes within each assembly have registrable arcuately extensive ports. At least one of the tubes in each assembly is rotatable with respect to the other and has a drive connection with the press drive for rotation in respectively oppositely directions so that upon release of a sheet above the delivery pile the ports in each assembly are progressively moved into and then out of arcuate register to produce jets of air which sweep mutually outwardly from the sheet center line so that contact with the pile is made first at the center of the sheet followed by a flattening of the sheet against the pile progressively to the latter edges accompanied by prompt progressive squeezing of the cushion of air from under the lateral edges of the sheet. Preferably the inner tube of each assembly is rotatable and includes a plurality of ports in an arcuate series, with the outer tube having a free sector and being held relatively stationary but adjustable to vary the angle of sweep.