Packaging materials in flexible walled containers by folding (printed) thermoplastic sheet about a cylindrical mandrel and stepping the resulting tube forward e

摘要

Packaging materials in flexible walled containers by folding (printed) thermoplastic sheet about a cylindrical mandrel and stepping the resulting tube forward either by movements of the mandrel or of clamps associated with a heat sealing device which alternately constricts and clamps one end of a section to be filled with the contents to be packaged and heat-seals the other end of the pack. Successive packs are produced in alternating heat to head and tail to tail pairs (requiring alternate inversion of printing on the original sheet). Capable of high speed packaging operations incorporating use of a detachable re-usable closure or clamp.