Newell C Rodewald

US Patent:

39411249, Mar 2, 1976

Filed:

Jan 21, 1969

Appl. No.:

4/792874

Inventors:

Newell C. Rodewald - Manhattan Beach CA
Jerry E. Sinor - Longmont CO

International Classification:

A62B 706

US Classification:

128142

Abstract:

A process for supplying the proper amount of oxygen in a breathing gas mixture of at least one inert gas for use at any pressure by passing the gas mixture through the liquid phase of a cryogenic liquid-vapor system containing oxygen and thereby saturating with oxygen the gas mixture at the system pressure. The saturation concentration of oxygen in the gas stream is controlled to the desired oxygen partial pressure substantially independent of the total pressure of gas mixture by controlling the temperature of the two-phase cryogenic system. A device embodying the process includes oxygen in liquid-vapor form within a container to which are connected gas conduits, one for delivering the saturated breathing gas mixture to a user and the other for returning the exhaled gas to the container. A filter in the return conduit extracts carbon dioxide and water vapor. The return gas is cooled to the cryogenic temperature and the saturated gas is heated to breathing temperature by a heat exchanger thermally connecting the two conduits.