Patent ID: 6524434
Filing Date: 2003-02-25
Classification: B29C,Y10T

Abstract:
A tube-forming apparatus in a bag-forming, fifting, and sealing machine, comprising a device in which a packing material belt (1) with a heat-sealing layer on an inside is formed into a tube (2), wherein edge regions (3, 4) of the packing material belt (1) are placed inside to inside, having a longitudinal seam heat-sealing device (15) with a heating body (20) that has an electrical resistance wire (21) and heats the edge regions (3, 4) of the continuously advanced packing material belt (1), and a pressing device (16), said pressing device presses the heated edge regions (3, 4) together and cools them, the resistance wire (21) of the heating body (20) is disposed in a U shape with closely adjoining legs (22, 23) between two thin, heat-resistance strips (24) that have a low coefficient of friction, and that the heating body (20) is associated with the tube-forming apparatus (10) in such a way that the edge regions (3, 4) of the packing material band (1) to be sealed against one another rest in a sliding fashion with their insides against the heating body (20) that protrudes between them during the advancing motion of the packing material belt (1).