| 摘要 |
Method and apparatus for forming multiple bags from thin plastic film which have at their opposite upper edges interconnection elements in the form of a rib and a furrow, said bags being formed with tubular film formed by continuous extrusion, said tube having a first pair of rib-type elements, a second pair of diametrically opposed rib-type elements, a first pair of furrow-type elements between said pairs of rib-type elements and a second pair of furrow-type elements diametrically opposed to said first pair, said elements of said pairs being separated by a short distance and being located in the inner surface of the tube, each one of the elements of said pair of rib-type elements being aligned with each one of the elements of said adjacent pair of furrow-type elements when the tube is flattened in order to form first and second sets of lined pairs of rib-type and furrow-type elements, a continuous groove being formed between the elements of one layer in a set and the elements of the other layer in the other set, the tube then being folded in such a manner that an element adjacent to the groove of the first set is folded on the second set and such that an element adjacent to the groove of the second set is folded on the first set, thus forming two continuous strips of film with a double interconnection profile. |
