Tamper indicating closure system utilizing axially extending ratchet
US4930647A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 1989 |
| Grant date | Jun 5, 1990 |
| Priority date | — |
| Expiry date | Jan 24, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D41/3409
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A thermoplastic closure comprises an annular tamper band connected to the skirt of a cap by frangible bridges. In one embodiment of the closure, axially extending ratchet teeth on the bottom of the tamper band cooperate with axially extending lugs on a container shoulder or transfer bead. As the cap is screwed onto the container, the teeth ratchet over the lugs. When an attempt is made to unscrew the cap, the ratchet teeth engage the lugs to prevent rotation of the tamper band so that continued application of an unscrewing force to the cap results in fracturing of the bridges along the intersection of reduced cross-section between the bridges and the skirt. The axial length of the engaging surfaces of the ratchet teeth and lugs is sufficient that they remain axially aligned through any initial axial separation of the cap and transfer bead until the ratchet teeth and lugs engage. In another embodiment of the closure, axially extending projections on the tamper bead are bent circumferentially by the lugs on the container as the closure is screwed onto the container. The bent projections wedge against the lugs as the cap is unscrewed to prevent rotation of the tamper band with the cap…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.