摘要 |
A heat sealing assembly, for sealing at least two layers of thermoplastic film, is disclosed. It comprises a first jaw (11) and a second jaw (not shown), an electrical impulse heat sealing element (12) mounted on the first jaw (11), electrical terminals (17) connected to the element (12), and at least one electrically and thermally insulating film or tape (14) between the first jaw (11) and the heat sealing element (12). At least one of said jaws is capable of transverse motion and is adapted to collapse a tubular film made from the thermoplastic film and passing between said jaws. The improved heat sealing assembly has a first jaw (1 I) which has a thermally insulating material (16) embedded therein along a length abo ut equal to the width of the flattened film and hav- ing a width at least as great as the width of the sealing element. |