| 摘要 |
The invention relates to a method for manufacturing bags having a single layer or multi-layer outer bag, preferably made of paper, and an inner bag preferably made from a web of synthetic plastics material. The inner bag has a Z-fold formed therein, and this is opened out when the bag is in use. In the method of the invention, a transverse weld seam is formed in the tubular material for the inner bag before the Z-fold is formed so that the base of the inner bag can be hermetically sealed. The tubular material for the inner bag is conveyed out of a substantially horizontal conveying direction into a slightly rising conveying direction and this makes it possible to form a loop of material, which is required for forming the Z-folds. The direction of travel of the tubular material for the insert bag is then reversed and this enables the part of the Z-fold which points in the direction of travel to lie on the side of the tubular material which is against the web for the outer bag.
|
