Device for converting an intermittently moving web in a continuously moving web, in particular for the production of from a thermoplastic plastic film bag

摘要

An intermittently moving web is changed over into a continuous movement, and partic. in the prodn. of lengths such as bags (sepd. by perforations) from a double-layer thermoplastic film which is drawn off a roll and then through an intermittent device for welding and perforating across the width (e.g. width or length of a bag) before being finally reeled. The intermittently produced web is moved further forward over two separate surfaces so as to be festooned between them; the end of the loop concerned is pulled over the second surface where a vacuum is applied; from there the web is drawn under tension and reeled up. ADVANTAGE - The system is extremely simple. It enables the material to be cooled at its welds.