摘要 |
The overlapping edges of a film of thermoplastic material formed into a tube are welded by the tool of an ultrasonic welder, which works directly with the filling tube of a packing machine. The machine packs materials ranging from fluids to powders and granulates, into a tube formed by turning a strip of film over a guide plate on to the outer surface of the tube, on which it is welded, filled and sealed by transverse seams spaced out at intervals. The transverse seams are produced by the tools of a second welding device which include the ultrasonic tool and a holding-up punch. These are both movable transversely to the line of motion of the tubular film and they have contact surfaces in the form of an "S" or a "Z". Used to provide a tubular bag machine for the packing of shampoos, fats, cheeses, sausage meat, slurries of explosives, and granular matter. The machine works at much higher speeds than those using glue, and welds thick films without a dangerous level of heat being generated. In addn. the vibration set up by the waves displaces particles which otherwise would remain in the seam. |