| 摘要 |
In this multi-layer sack, an inner latch (4, 5) which seals the sack bottom in the region of the bottom edges is formed by tabs (9, 9' and 10, 10') which start from the separating line (3) of the inner web of material (1) and are arranged in such a way that they lie congruently on one another after the forming of the webs of material to form the tube and are bonded to one another at this point. The inner latch can thus be formed without additional use of material and it automatically maintains its correct position in the bottom. The transverse edges of the corner folds can also be covered by it. A sack of this type can also be produced quickly and simply since, for this purpose, the appropriate incisions for forming the tabs only need to be made in the inner layer (1) of material. The device for carrying out the method only requires an additional cutting device for the incisions and a folding device and a gluing device for the tabs formed. <IMAGE> |
