| 摘要 |
Transparent outer wrappers for cigarette packets are prepared by advancing a continuous strip of overwrap material (1) along a given feed path (P) in a given direction (A), piercing a predetermined area (2) of the strip with a series of slits (4) spaced apart one from another and extending nominally transverse to the feed direction (A), and bonding a narrow ribbon (7) to the strip (1) along the predetermined area (2), aligned on at least one portion (4a) of the slits (4); the strip then passes under a blade (12) shaped so as to cut a series of "U" notches (10) spaced apart one from the next, each creating a pull tab (11) at the end of the ribbon (7), before being divided ultimately into leaves (13) by a pair of contrarotating cutter rollers (14) equipped with respective blades (14a). Each single leaf (13) serves as a wrapper (16) for a relative pack, fashioned so that when torn open by pulling the ribbon (7), the ribbon encounters the slit (4) and initiates two break lines (17) extending away from the ribbon (7) on either side to facilitate the removal of the wrapper (16) in its entirety. |
