| 摘要 |
<p>1. A two position punch lock for cartons for securing together a pair of panels of the carton in overlapping relationship comprises a locking tab (30) struck from one (12) of the panels and a locking aperture (42) provided in the other (20) of the panels and arranged to receive and retain the locking tab. The locking tab has opposed lateral shoulders (32, 34) between a base (36) and a nose (38) of the tab and the width across said locking tab at its shoulders is broader than the greatest width of the locking aperture and the width of the extremity of the nose is narrower than the least width of said locking aperture. Each shoulder is formed with a deformable marginal portion formed by a cut (C1, C2) extending inwardly from the edge of the shoulder. This marginal portion is deformed by engagement with the adjacent lateral edge (44,46) of the locking aperture to lock the locking tab in the locking aperture. <IMAGE></p> |
