Plastic spool especially for photographic films

摘要

The plastics flap (4) is deflected over the plastic hinge (8) towards the spool's core (2). The cylindrically externally rounded transition surface between the slot's (3) axial top surface and the spool-core's outer surface has at least one protuberance (7) which can fit into a matching-shaped hole (6) in the end (5) of the strip. The protuberance has a triangular cross-section of which the surface on the inside of the spool forms an angle greater than 90, and esp. 120 to 180 deg. with the slot top inner surface. The plastic flap is curved over the plastics hinge (8) towards the protuberance and the two fused together.