Tentering chain with a continuously adjustable chain pitch for treating film webs simultaneously in two axial directions

US5161674A · kind A · utility

Assignee

• Lindauer DORNIER Gesellschaft mbH · DE

Inventors

• Andreas Rutz · Gettorf, DE
• Rudolf Langer · Gettorf, DE
• Hubert Becher · Tettnang, DE
• Klaus Buttenbender · Friedrichshafen, DE

Key dates

• Filing date: Nov 14, 1990
• Grant date: Nov 10, 1992
• Expiry date: Nov 14, 2010

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29C55/165
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A tentering chain is equipped with a mechanism for the stepless, continuous adjustment of the chain pitch which is the on-center spacing between two neighboring chain link journal bolts or pins. Such chains are used for this simultaneous, biaxial treatment of synthetic material films or webs. For this purpose, the chains carry tenter bodies with hooks or clamps for gripping the film edge. The tenter bodies carry guide rollers which engage guide rails along the travel path of the tentering chain. In order to dimension the tenter body with its gripping elements as small as possible, while still permitting a large shrinking or stretching of the film web, the chain link journal bolts or pins are mounted in the respective tenter body for an adjustment of the pin position in a direction of the chain travel. In all positions of the journal pin or pins these pins extend perpendicularly to the longitudinal direction of the chain. Two neighboring pins are interconnected by a coupling device which in turn is driven by a drive mechanism for adjusting the pitch by an adjustment lever operable, for example, by a control rail. A lock holds the pins in an adjusted position.