APPARECCHIO PER SALDARE A CALDO, IN CONTINUO,FILMS TERMOPLASTICI

摘要

The present invention relates to a device for continuous hot-sealing of thermoplastic films. This device comprises a sealing head, said sealing head being provided with two rip cord electric resistances that are heated by causing an electric current to flow theretrough and being made of a material the electric resistance of which is proportional to the temperature, said sealing head being caused to rapidly vibrate against a counter-plate so as to cause the thermoplastic film to be sealed to be rapidly pounded as it glides between said head and said counter-plate. The sealing of the thermoplastic films is brought about by the synergic action of the heat of the resistances and of the pressure due to the pounding.