Apparatus for establishing and maintain a constant-pressure environment

Claim 1

An apparatus comprising: A. A generally gastight glove box enclosure including one or more gloves; B. A source of gas of the same type as that to be utilized in said enclosure, said source being at a pressure above the operating pressure of said enclosure; C. Means for admitting gas from said source to said enclosure when the pressure differential between the interior of said enclosure and a centrifugal blower vacuum source falls below a predetermined level; D. Means for sensing said pressure differential between the interior of said enclosure and the blower; and E. A centrifugal blower vacuum source, said blower producing a pressure essentially constant when gas flow through the blower is varied, said blower being in communication with the enclosure through a bubbler pressure-relief valve, said bubbler acting as both a means for sensing the pressure differential between the interior of the enclosure and the blower, and as a means for exhausting gas from said enclosure to said blower when the pressure differential rises above a predetermined value; whereby, as said pressure differential tends to change, the gas-admitting means or bubbler, respectively, admits or exhausts gas so as to maintain an operating pressure within said enclosure within a predetermined range.

Claim 2

An apparatus comprising: A. A generally gastight glove box enclosure including one or more gloves; B. A source of gas of the same type as that to be utilized in said enclosure, said source being at a pressure above the operating pressure of said enclosure; C. Means for admitting gas from said source to said enclosure when the pressure differential between the interior of said enclosure and a centrifugal blower vacuum source falls below a predetermined level; D. Means for sensing said pressure differential between the interior of said enclosure and the blower; and E. A centrifugal blower vacuum source, said blower producing a pressure essentially constant when gas flow through the blower is varied, said blower being in communication with the enclosure through a bubbler pressure-relief valve, said bubbler acting as both a means for sensing the pressure differential between the interior of the enclosure and the blower, and as a means for exhausting gas from said enclosure to said blower when the pressure differential rises above a predetermined value; whereby, as said pressure differential tends to change, the gas-admitting means or bubbler, respectively, admits or exhausts gas so as to maintain an operating pressure within said enclosure within a predetermined range.