Method and apparatus for making skirtless seals
AssigneeCMD Corporation
InventorPaul A. Selle
Life of this patent
Estimating the term…
Abstract
A machine and method for converting film into bags or other articles includes a web traveling from an input section to a rotary drum, to an output section. The rotary drum includes at least one seal bar with a sealing zone and a weakening zone, or it can include or at least one sealing die that extends in the machine direction. The single sealing zone or sealing die may be a heated perforator, and may include a heating wire. The heating wire may be an NiCr wire stitched into the heater, and be disposed on a cap or on the seal bar. The weakening zone may create a line of weakness that is uniform or varies in intensity. The sealing zone may include temperature zones, cartridge heaters, cooling air, or heated air, or a source of ultrasonic, microwave or radiative energy.
Claims16
A converting machine, comprising:
- an input section;
- a rotary drum, disposed to receive a web from the input section, wherein the rotary drum includes at least one seal die disposed thereon;
- an output section, disposed to receive the web from the rotary drum;
- and
- wherein the at least one seal die includes a weakening zone that forms a perforation with an auxiliary sealed area about the perforation, wherein the weakening zone extends in the machine direction at least as far as it extends in the cross machine direction.
A method of converting film into a plurality of articles, comprising:
- feeding a film to a rotary drum;
- forming, on the film, a plurality of perforations with auxiliary sealed areas about the perforations using at least one seal die disposed on the rotary drum such that the perforations and auxiliary sealed areas extend in the machine direction at least as far as they extends in the cross machine direction;
- and
- forming a perforation between successive articles.
A machine for converting film into a plurality of articles, comprising:
- means for feeding a film to a rotary drum;
- means for forming, on the film, a plurality of perforations with auxiliary sealed areas about the perforations such that the perforations and auxiliary sealed areas extend in the machine direction at least as far as they extends in the cross machine direction;
- and
- means for forming a perforation between successive articles.
Dependencies are inferred from the claim text.