CLOSURE HAVING VENTING MEANS

摘要

A closure arrangement, particularly for pressurised containers such as bottles containing carbonated drinks, comprises a cap member (1) with locking means such as a screw thread for sealing the cap onto the container. The cap member has an opening (9) normally closed and sealed by a closure member (5) located within the cap member, the closure member being biased into its normally closed condition when the cap member is fitted to the container, and vent means (11) are associated with the closure member for releasing fluid pressure only when the closure member is moved against the bias pressure to unseal said opening. The closure member (5) is preferably pre-biased into the closed condition and may comprise a diaphragm of resilient material. The opening may be shaped as a nearly circular slit (9A) to provide an area (15) which is depressed to release the fluid pressure. The closure arrangement eliminates the possibility of the cap member flying-off the container by first reducing fluid pressure before opening.