Portable life support system

Abstract

The invention in its preferred embodiment is a portable life support system providing the wearer of a garment with temperature regulation and a breathable atmosphere using cryogenic technology. Wherein a liquid cryogen is vaporized by heat exchange with the wearers body and the vaporized cryogen is delivered to the wearer as a breathable atmosphere.

What is claimed is: 
     
       1. A portable life support system, comprising: a liquid cooled garment;   .Iadd.a backpack supporting the life support system comprising:.Iaddend. an orientationally independent dewar for containing liquid cryogen;   means for circulating liquid cryogen from said dewar in heat exchange relation with .[.the.]. .Iadd.a .Iaddend.cooling liquid so as to cool the wearer of the garment and vaporize the liquid cryogen; and     means for delivering vaporized cryogen to the wearer of said garment for breathing purposes.   
     
     
       2. The portable life support system of claim 1, wherein the .[.heat exchanging.]. .Iadd.circulating .Iaddend.means comprises: an insulated housing;   a loop for circulating the cooling liquid through the interior of the garment and the housing; and   means for circulating liquid cryogen through the housing intermediate the .[.source.]. .Iadd.dewar .Iaddend.and the delivering means.   
     
     
       3. The portable life support system of claim 2, wherein the delivering means includes a loop for recirculating vaporized cryogen to the wearer of said garment. 
     
     
       4. The portable life support system of claim 1, wherein said orientationally independent dewar is a positive expulsion dewar. 
     
     
       5. The portable life support system of claim 4, wherein said positive expulsion dewar is externally charged. 
     
     
       6. The portable life support system of claim 4, wherein said positive expulsion dewar is self-pressurizing. 
     
     
       7. The portable life support system of claim 1, wherein said means for delivering vaporized cryogen is an open circuit system. 
     
     
       8. The portable life support system of claim 1, wherein said means for delivering vaporized cryogen is a semi-closed system. 
     
     
       9. A portable life support system, comprising: a liquid cooled garment;   .Iadd.a backpack supporting the life support system comprising:.Iaddend. an orientationally independent dewar for containing and delivering liquid cryogen; and   a heat exchanger for exchanging heat between the cooling liquid and the liquid cryogen delivered from the dewar.     
     
     
       10. The portable life support system of claim 9, wherein said orientationally independent dewar is a positive expulsion dewar. 
     
     
       11. The portable life support system of claim 10, wherein said positive expulsion dewar is externally charged. 
     
     
       12. The portable life support system of claim 10, wherein said positive expulsion dewar is self-pressurizing. 
     
     
       13. A portable life support system, comprising: a liquid cooled garment through which cooling liquid may be circulated;   .Iadd.a backpack supporting the life support system comprising:.Iaddend. a source of liquid cryogen; .Iadd.and.Iaddend.   means for delivering liquid cryogen from said source at a varying rate in heat exchange relation with the cooling liquid to cool the cooling liquid, thereby varyingly regulating the temperature of the cooling liquid.     
     
     
       14. A portable life support system as in claim 13, wherein the circulation rate of the liquid cryogen is correlated to the respiration rate of the system user to regulate the temperature of the cooling liquid as the system user's respiration rate varies. 
     
     
       15. A portable life support system as in claim 14, wherein the liquid cryogen is vaporized and the delivering means includes an open-demand breathing loop. 
     
     
       16. A portable life support system as in claim 13, wherein the liquid cryogen is vaporized and the delivering means includes a semi-closed breathing loop. 
     
     
       17. A portable life support system as in claim 13, wherein the cooling liquid, when circulated, is circulated at a constant rate. 
     
     
       18. A portable life support system as in claim 13, wherein said source is an orientationally independent dewar. 
     
     
       19. A portable life support system, comprising: a liquid cooled garment through which cooling liquid may be circulated;   .Iadd.a backpack supporting the life support system comprising:.Iaddend. a source of liquid cryogen;   means for circulating liquid cryogen from said source in heat exchange relation with the cooling liquid to cool the cooling liquid and vaporize the liquid cryogen; and     means for delivering vaporized cryogen to the wearer of said garment for breathing purposes, said delivering means delivering vaporized cryogen at a varying rate, thereby varyingly regulating the temperature of the cooling liquid.   
     
     
       20. A portable life support system as in claim 19, wherein the delivery rate of the liquid cryogen is correlated to the respiration rate of the system user to regulate the temperature of the cooling liquid as the system user's respiration rate varies. 
     
     
       21. A portable life support system as in claim 20, wherein the delivering means includes an open-demand breathing loop. 
     
     
       22. A portable life support system as in claim 19, wherein the delivering means includes a semi-closed breathing loop. 
     
     
       23. A portable life support system as in claim 19, wherein the cooling liquid, when circulated, is circulated at a constant rate. 
     
     
       24. A portable life support system as in claim 19, wherein said source is an orientationally independent dewar. .Iadd.25. A portable life support system, comprising: .Iadd.a backpack housing means supporting a life support system including: .Iadd.an orientationally independent dewar for containing liquid cryogen;   .Iadd.a heat exchanger for exchanging heat between liquid cryogen and a heat source; and   .Iadd.means for delivering liquid cryogen from said dewar to said heat exchanger in heat exchange relation with the heat source so as to provide vaporized cryogen for breathing purposes..Iaddend..Iadd.26. The portable life support system of claim 25, wherein said dewar includes said delivering means..Iaddend..Iadd.27. The portable life support system of claim 25, further comprising     .Iadd.a liquid cooled garment exposed to the body heat of its wearer and thermally connected to said heat exchanger, whereby the cooling liquid in said garment exchanges heat with the liquid cryogen in said heat exchanger to cool the wearer and provide vaporized cryogen to the wearer for breathing purposes..Iaddend..Iadd.28. The portable life support system of claim 25, wherein   .Iadd.the heat source is ambient air..Iaddend..Iadd.29. The portable life support system of claim 25, wherein   .Iadd.said delivering means comprises an open-demand breathing loop through which the vaporized cryogen is delivered..Iaddend..Iadd.30. The portable life support system of claim 25, wherein   .Iadd.said delivering means comprises a semi-closed breathing loop through   
     
     
        which the vaporized cryogen is delivered..Iaddend..Iadd.31.  As in claim 9, including .Iadd.means for controlling the temperature of the cooling liquid..Iaddend..Iadd.32. As in claim 27, including   .Iadd.means for controlling the temperature of the cooling   
     
     
        liquid..Iaddend..Iadd.33.  A portable life support system, comprising: .Iadd.a housing means supporting a life support system of a size and shape to be carried as a backpack including: .Iadd.an orientationally independent dewar for containing liquid cryogen;   .Iadd.heat exchange means for circulating liquid cryogen from said dewar in heat exchange relation with a heat source so as to provide vaporized cryogen for breathing purposes; and   .Iadd.means for delivering said vaporized cryogen to the wearer of said backpack for breathing purposes..Iaddend..Iadd.34. A portable life support system according to claim 33 which further includes:     .Iadd.a heat exchanger between said heat exchange means and said means for delivering said vaporized cryogen to vaporize any excess liquid cryogen and warm said vaporized cryogen to a breathable temperature..Iaddend.