Apparatus for breaking weakened portions of running webs or the like

US4284221A · kind A · utility

Assignee

• Agfa-Gevaert NV · BE

Inventors

• Erich Nagel · Anzing, DE
• Franz Ziegler · Munich, DE
• Ferdinand Schaner · Munich, DE

Key dates

• Filing date: Nov 28, 1979
• Grant date: Aug 18, 1981
• Expiry date: Nov 28, 1999

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T225/393
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

Apparatus for separating successive sections of a running web wherein neighboring sections are connected to each other by weakened (e.g., perforated) web portions has a first and a second web driving unit. The second unit is located behind the first unit, as considered in the direction of transport of the web, and its speed is reduced below the speed of the first unit (and/or the speed of the first unit is increased above that of the second unit) when a weakened portion is located between the two units. This results in automatic separation of the preceding section because the tensional stress upon the weakened portion behind the preceding section suffices to destroy such weakened portion. The weakened portions are monitored by a detector which transmits short-lasting signals to change the speed of the first and/or second unit when a weakened portion advances beyond the second unit but is yet to reach the first unit. When a separating step is completed, the speed of the two units is again the same.