摘要 |
A closure device for serving the frangible section between the cap and body of a blow-fill-seal plastic container comprising an expandable ring constructed and arranged to encircle the container cap, an outer ring having at one end internal threads compatible with the external threads located on the neck of the container body and a tamper proof overcap. Counterclockwise rotation of the outer ring transmits uniform upward pressure to the expandable ring which causes tension between the container cap and container body, rupturing the frangible line of weakness on the container, to permit opening of the container. Conversely, clockwise rotation of the outer ring causes compression to rupture the frangible line of weakness. Subsequent counterclockwise rotation opens the container. In either case the container cap is retained within the outer ring and is replaceable on the container. |