Apparatus for producing machine-direction heat seals

摘要

Apparatus for heat sealing a pair of hems in a moving web of film having structure including a pair of spaced surfaces over which each hem of the pair of hems is adapted to pass. A first block is supported by the structure with respect to one of the surfaces and on one side of one of the hems. A plurality of rollers is mounted on the first block at spaced locations in tandem for engaging the film along the path of the heat seal to be formed in the one hem. A second block is supported by the structure with respect to the other of the surfaces and on one side of the second hem. The second block has a plurality of rollers mounted thereon at spaced locations in tandem for engaging the film along the path of a heat seal to be formed in the second hem. Heaters are provided for each of the blocks and the respective plurality of rollers whereby movement of the hems through the heat sealing apparatus causes the plurality of rollers mounted on the blocks to rotate and produce the heat seals in the pair of hems. Mounted on the structure between the pair of hems is a plurality of back-up rollers for engaging the film along the path of the heat seals to be formed in the hems and cooperating with the heated rollers on the blocks in creating the heat seals in the pair of hems.