Mechanism to evacuate and then expose e.g. cans to inert gas pressure - before sealing has openable chamber with valved vacuum and gas connections and valve-connected to vessel to store gas during chamber opening

摘要

Mechanism for evacuating not yet sealed cans etc. and then exposing them to an inert gas before sealing comprises a chamber openable to introduce and remove cans and sealingly re-closable. The chamber is connectable to vacuum pump(s) via a valve and to one or more, e.g. inert, gas pressure supplies via another valve. The chamber is connectable to a gas buffer storage vessel via a third valve, the arrangement being such that, during the intervals when the chamber is opened to remove and receive cans, a limited proportion of the insert gas can be stored for re-use.