Device for the flattening of sheets by means of suction

US4119309A · kind A · utility

Assignee

• Roland Offsetmaschinenfabrik Faber & Schleicher AG

Inventors

• Peter Mayer · Neumarkt an der Ybbs, AT
• Claus Simeth · Mühlheim, DE

Key dates

• Filing date: Oct 25, 1977
• Grant date: Oct 10, 1978
• Expiry date: Oct 25, 1997

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B65H2301/51256
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

A device for removing curling tendency in sheets, particularly sheets fed to printing presses, in which the sheets are conveyed over two beam-like supporting members arranged transversely with respect to the direction of sheet movement and presenting supporting surfaces which are spaced parallel to one another on one side of the sheet to define a groove in between them. Suction is applied within the groove to draw a passing sheet downwardly into the groove to produce a relatively sharp concave bend in the sheet thereby to counteract the curling tendency. The cross-sectional profile of the groove is variable by a movable member to vary the profile of the groove and hence the degree of sharpness of the bend, thereby permitting the degree of correction to be varied while keeping the suction substantially constant. The device, in both preferred and alternate embodiments, has provision for removing curling tendency in opposite directions.