Abstract: A rotary bristle brush, particularly adapted for use in a decelerating conveyor for shingling sheets, operates over a preload surface that subjects the moving bristles to an increasing bending deflection. The bristles are released from the preload surface just above the sheets entering the shingling conveyor to allow the ends of the preloaded bristles to spring downwardly into contact with the sheet. The contact force of the bristles helps drive the sheet downwardly onto the shingling conveyor which may be a vacuum conveyor.

Abstract: A vacuum-assisted hot plate is used to precondition webs, such as paper webs used in the manufacture of corrugated paperboard. The vacuum-assisted preheater has a web supporting and heating surface separated into four sections, namely: an input section, a central upstream section, a central downstream section, and an output section. The sections are separated by three vacuum channels that are sized wide enough to prevent clogging from paper dust. The central upstream section and the central downstream section have convex surfaces. Vacuums applied to the vacuum channels provide a normal force to pull the traveling web against the heated surface, whereas the convex configuration of both the central upstream section and the central downstream section provide a normal force pushing on the paper web in the opposite direction. The result is effective positive contact of the traveling web against the heated surface, thereby promoting effective heat transfer.

Abstract: A conveyor system wherein individual sheets are conveyed from a cutter at a given speed, are increased in speed before passing through a vacuum conveyor shingling section, are slowed down at the shingling section, and then normally proceed at a slowed down speed to the stacker which is adapted to stack a fixed number of sheets before discharging a stack. The sheets are basically handled in accordance with the device disclosed in U.S. Pat. No. 4,200,276. The vacuum shingler of the invention includes a slow-down device, such as a smoothing wheel or spring fingers, positioned above the vacuum conveyor section to nip the leading edge of the individual sheets before they contact the vacuum conveyor. The slow-down device acts to reduce the tendency of lightweight paperboard sheets to fold transversely or buckle across their width.

Abstract: A vacuum shingler for a plurality of sheets (9) traveling in succession through an upstream infeed nip (13) is provided with a vacuum modulating control which applies sheet slow-down forces primarily to only the tail ends of the sheets. In one embodiment, the control provides a substantially "on-off" vacuum operation, with the vacuum "off" when the leading end portion of the sheet is adjacent the vacuum plenum opening(s) (39), and with the vacuum "on" when the tail end portion of the sheet is adjacent the opening(s). In another embodiment, the control modulates the vacuum so that it is at a basically unshingling low or reduced level when the leading end portion of the sheet is adjacent the opening(s), and is at a substantially increased high level when the tail end portion of the sheet is adjacent the opening(s) so that basic shingling occurs.

Abstract: An anti-skew device is positioned between a stacker input nip and stacker in a shingled sheet conveying apparatus. A plurality of fingers are mounted along a transverse mounting element disposed between the nip and the stacker. The fingers are designed to normally hang downwardly, but some of them are raised upwardly as they are engaged by a sheet passing therebeneath, and rest on top of the moving shingled sheets. The transverse mounting element is longer than the width of the sheets and some of the fingers disposed outwardly of the sheets continue to hang down and provide an alignment guide to hold the longitudinal sheet edges against shifting or skewing. The downwardly hanging outer fingers are disposed adjacent the side edges of the formed stack to hold the upper sheets therein in alignment.