Plastic bag making machine

摘要

A machine for making plastic bags, such as trash or garbage bags, includes a rotary sealing drum of variable diameter, the drum including one or more sealing bars for cross-sealing a flattened plastic film tube passing through the machine. A blanket tensioning system surrounds the drum and is adjustable to compensate for different drum diameters. The sealed film passes over a chill roll after leaving the drum-blanket assembly and is drawn over folding boards by pull rolls. The sealed and folded film is then perforated by a fly knife and is preferably also cut on the sides to produce a connected series of bags which may easily be separated from one another to make the bags suitable for easy dispensing packages. A variator assembly may also be provided to insure a proper skirt length between the cut-perforation and the bag seal.