Warm air weathermask

Claim 1

Apparatus for preconditioning air to be breathed by a user of said apparatus, said apparatus comprising in combination: housing means having a periphery contoured to fit closely against the user's face, an intake conduit defined by an enclosed tube within the housing, the tube having a distal end communicating with a source of breathable, oxygen-containing gas and breathing means at its proximal end for communicating with the respiratory tract of the user, said intake conduit being operative to convey said oxygen-containing gas from said source to said respiratory tract, means associated with said intake conduit for preventing substantial reverse flow of gas from said respiratory tract toward said source, an exhaust conduit comprising an enclosed tube within the housing, the tube enclosing a portion of the intake conduit, the intake conduit being essentially concentric therewithin, an appropriate receiver, the exhaust conduit having a distal end communicating with said appropriate receiver for gases exhausted from said respiratory tract and a proximal end communicating with said breathing means communicating with the respiratory tract of said user, said exhaust conduit being operative to convey said gases exhausted from said respiratory tract to said receiver, and means associated with said exhaust conduit for preventing substantial reverse flow of gas from said receiver toward said respiratory tract, said intake conduit and said exhaust conduit being juxtaposed in indirect heat-exchange relationship wherein said conduits are disposed adjacent said periphery of said housing means to be closely adjacent to the face of the user, thereby improving heat conservation in the system comprising said apparatus and said face, and minimizing loss of heat from said system to the ambient atmosphere.