.~.~ And means for reducing, and maintaining, pressure in housing below that of environment
DEFINITION
Classification: 494/61
With means for reducing, and maintaining, pressure in housing below that of environment:
(under subclass 60) Apparatus wherein the enclosing or shrouding structure is provided with means for (a) at least partially evacuating the structure relative to its surroundings and (b) keeping it approximately at that degree of evacuation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
25, for a separator provided with means for furnishing an auxiliary fluid and wherein that fluid is a gas other than air. In this regard, it should be noted that, in the event that the gas is intended to replace air as the fluid present in the interior of the structure, it may be necessary to first draw off some portion of the air.
39, for a separator which includes sealing means for protecting an evacuated, bowl-enclosing housing against gaseous infiltration.
