| 摘要 |
1,068,146. Seaming non-metallic sheet material. TEPAR A.G. Feb. 24, 1966 [March 6, 1965], No. 8197/66. Heading B5K. In a method of joining parts 5, 6 of sheet or web material by an overlap seam, at a distance of substantially the width of the joint from the free edge 4 of the part 5, there is produced an elevation or ridge 7 parallel to the edge 4 and the part 6 is caused to overlap the part 5 to such an extent that the free edge 8 of the part 6 in the finished joint engages the elevation or ridge 7. In the embodiment shown, the parts 5, 6 each comprise a paper layer 1 and two synthetic plastic coating layers 2, 3, e.g. polyethylene or polypropylene. The elevation or ridge 7 may be produced by a stamping wheel running on the opposite side of the part 5 or by creasing or bending the material. Sealing is effected by pressing the parts 5, 6 between a heated jaw and a support. The invention is applicable to forming the longitudinal seam in a tube formed from a web prior to forming packages. |
