Method and apparatus for subdividing webs of coherent paper sheets

US4669344A · kind A · utility

Assignee

• E.C.H. Will GmbH · DE

Inventor

• Friedhelm Herrig · Hamburg, DE

Key dates

• Filing date: Apr 18, 1986
• Grant date: Jun 2, 1987
• Expiry date: Apr 18, 2006

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T83/2081
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

Successive watermarks on a running web of coherent paper sheets are monitored by a scanner which generates defect signals in response to detection of watermarks outside of selected portions of the respective sheets, and the cross cutter which severs the web to form discrete sheets is then adjusted to separate the respective sheets from the next-following sheets with a delay or prematurely so that the sheets bearing the improperly positioned watermarks are too short or too long. Such defective sheets are segregated from satisfactory sheets downstream of the cross cutter in properly delayed response to generation of defect signals by the scanner.