Method and apparatus for controlling of films welding machines, in particular for the production of of the tube - or semitubular sheets of thermoplastic plastic bags or sacks welded

摘要

The invention concerns a method and device for controlling sheet-welding machines, in particular machines for manufacturing bags made by welding continuous tubular or semi-tubular strips of thermoplastic material, the device having a pair of sheet-feed rollers (2) and a pair of welding bars (4, 5). In order to improve performance and to be able to adjust the device to adapt it to different materials and to permit different welding-bar positions, the device is driven by a reversing crank gear.