| 摘要 |
A one-piece reusable closure for home canning. The closure is adapted for sealing home canning containers, such as "Mason Jars." The closure has a one-piece threaded cap with a bonded annular closed-cell foam gasket at the periphery of the central cover panel positioned to seal against the jar lip. A central cover portion is dished outwardly and moves to an inwardly dished configuration when vacuum is developed in the container. When the closure is unscrewed, the central panel portion springs with an audible click to the outwardly dished configuration. Limiting projections extending downwardly into the gasket bear and compress the gasket material against the lip of the jar to control tightening of the closure on the jar so that, when the jar contents are heated, gases will be vented under the circumferentially spaced portions of the gasket. The closure may be initially fully tightened and need not be further tightened after heating and subsequent cooling of the jar to maintain the seal and vacuum within the container. |
