Patent classifications
B29C65/7471
Device for welding plastic films by means of hot gas
The invention relates to a device for the preferably continuous welding of plastic films by means of hot gas with at least one tubular body through which an electric current flows for the heating of the hot gas, wherein the device comprises at least one gas inlet opening (6, 106) and a plurality of gas outlet openings (12, 112) arranged next to each other, from which hot gas is blown onto the plastic film. It is provided that the at least one gas inlet opening (6, 106) is provided on a main tubular body (4, 104), which stands in gas communication with a plurality of branch tubular bodies (8, 108) at branching points (10, 110), wherein the branch tubular bodies (8, 108) each have at least one gas outlet opening (12, 112) and all the branch tubular bodies (8, 108) have electric current flowing through them.
Method and apparatus for making skirtless seals
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.
DEVICE FOR WELDING PLASTIC FILMS BY MEANS OF HOT GAS
The invention relates to a device for the preferably continuous welding of plastic films by means of hot gas with at least one tubular body through which an electric current flows for the heating of the hot gas, wherein the device comprises at least one gas inlet opening (6, 106) and a plurality of gas outlet openings (12, 112) arranged next to each other, from which hot gas is blown onto the plastic film. It is provided that the at least one gas inlet opening (6, 106) is provided on a main tubular body (4, 104), which stands in gas communication with a plurality of branch tubular bodies (8, 108) at branching points (10, 110), wherein the branch tubular bodies (8, 108) each have at least one gas outlet opening (12, 112) and all the branch tubular bodies (8, 108) have electric current flowing through them.