| 摘要 |
<p>1499478 Closures; sealing arrangements A L BOTKIN 9 March 1976 [28 April 1975] 09392/76 Heading B8T A one-piece closure, particularly for use in food preserving, comprises a central cover 22 with a threaded peripheral flange 28, an annular gasket 40 of closed cell foam material bonded to the closure adjacent the flange, and limiter means 42 embedded in the gasket material and extending downwardly of the cover 22 to locally compress portions of the gasket against a container lip more tightly than the gasket material which is circumferentially spaced from the limiter means is compressed against the lip when the closure is screwed on a container. The gasket material is preferably contained within a channel adjacent the flange 28, and the limiter means are in the form of at least three projections formed in the channel. The central cover 22 has, initially, an outwardly dished configuration, and when a vacuum is created in the container, the cover assumes a reversible inwardly dished configuration. The closure is secured on the container prior to heating to drive off steam and create a vacuum, further manipulation of the closure being unnecessary.</p> |
