Cryogenic air sampler
AssigneeAir Products and Chemicals, Inc.
InventorRalph C. Longsworth
Life of this patent
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Abstract
Environmental gases, e.g. air are collected in an apparatus wherein a sample bottle containing a metering orifice for admitting the gas is contained within and cooled by a bath of liquid cryogen thus creating a partial vacuum inside the bottle to draw gas into the bottle where it is condensed and stored. The apparatus includes a source of cryogenic refrigeration disposed in an evacuated space above the liquid cryogen to condense liquid cryogen boil-off. By combining evacuation and cryogenic refrigeration the sample bottle holder can be rapidly cooled to operating temperature.
Claims5
An apparatus for collecting and storing a sample of environmental gas comprising in combination:
- means to removably confine a sample bottle, said bottle having a metering orifice through which environmental gas can enter, in a bath of liquid cryogen said means including an evacuable space above said sample bottle allowing for liquid cryogen to boil-off and be confined therein;
- means to condense said cryogen boil-off thus maintaining said sample bottle at a temperature of just below the normal boiling temperature of said liquid cryogen;
- and
- means to effect rapid cool-down of said sample bottle.
Dependencies are inferred from the claim text.