Tamperproof closure
US4369889A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 1981 |
| Grant date | Jan 25, 1983 |
| Priority date | — |
| Expiry date | Jun 8, 2001 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D51/1688
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A thermoplastic closure for fitment to a container for packaging product capable of producing internal container pressure, e.g., carbonated beverages, is disclosed. The closure comprises a top wall and an annular sidewall downwardly depending from the top wall. A closure thread on the inside surface of the sidewall is provided for cooperation with the container neck thread to achieve fitment of the closure to the container. A sealing system adjacent the top wall of the closure provides sealing of the closure to the container. Venting structure is provided on either the closure or the container or both for venting of pressurized gas from the container upon loss of the seal when the closure is rotated to remove it from the container. A heat-shrinkable tamper-indicating means is attached to the lowermost edge of the sidewall of the closure. Application of heat to the tamper-indicating means causes it to shrink towards the container and to a point of interference with a container flange. A heat sink structure, such as an annular bead about the outside surface of the sidewall, is utilized to keep the sidewall at a temperature below that temperature which would normally cause the sidewal…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.