| 摘要 |
'Bottom-welded' bags of thermally weldable material are mfd. by (i) stepwise axial displacement of flattened tubular material; (ii) making a weld perpendicular to the tube axis at each pause between displacement steps; and (iii) cutting the tube parallel to the weld and in upstream or downstream proximity to the weld. - The novelty is that the cut is made by contacting the material during welding, with a rectilinear cutting element which extends and is moved perpendicular to the tube axis and parallel to the two thicknesses of the material. |
