Patent Number: 
Section: claims

1. A cryogenically cooled radiation shield device comprising:at least one first coil comprised of a superconductive material;a first inner conduit extending about an area to be shielded from radiation, wherein the at least one first coil is disposed within the first inner conduit so as to also extend within the first inner conduit about the area to be shielded from radiation;a first cryogen liquid disposed within the first inner conduit along with the at least one first coil;a first outer conduit extending about the area to be shielded from radiation, wherein the first inner conduit is disposed within the first outer conduit;a second cryogen liquid, different than the first cryogen liquid, disposed within the first outer conduit exterior of the first inner conduit, wherein the first cryogen liquid has a lower boiling point than the second cryogen liquid;thermal insulation surrounding the first inner conduit and positioned between the first inner conduit and the first outer conduit;at least one second coil comprised of a superconductive material;a second inner conduit and a second outer conduit extending about the area to be shielded from radiation and also extending about the first inner conduit and the first outer conduit, wherein the at least one second coil is disposed within the second inner conduit so as to extend within the second inner conduit about the area to be shielded from radiation, and wherein the second inner conduit is disposed within the second outer conduit; andfirst and third cryogen liquids disposed within the second inner conduit and the second outer conduit, respectively, wherein the third cryogen liquid is different than the first and second cryogen liquids. 2. A cryogenically cooled radiation shield device according to claim 1 wherein the first cryogen liquid comprises liquid helium and the second cryogen liquid comprises one of liquid oxygen, liquid nitrogen or liquid hydrogen. 3. A cryogenically cooled radiation shield device according to claim 1 further comprisingthermal insulation surrounding the second inner conduit and positioned between the second inner conduit and the second outer conduit. 4. A cryogenically cooled radiation shield device according to claim 3 wherein the second cryogen liquid comprises liquid hydrogen and the third cryogen liquid comprises liquid oxygen, and wherein the cryogenically cooled radiation shield device further comprises a fuel cell configured to receive boil off of the second and third cryogen liquids. 5. A cryogenically cooled radiation shield device according to claim 3 wherein the at least one first coil is spaced apart from the at least one second coil. 6. A cryogenically cooled radiation shield device according to claim 1 further comprising a first intermediate conduit extending about the area to be shielded from radiation, wherein the first inner conduit is disposed within the first intermediate conduit, and wherein the first intermediate conduit is disposed within the thermal insulation and the first outer conduit. 7. A method for cryogenically cooling a radiation shield device, the method comprising:providing at least one first coil comprised of a superconductive material;providing a first inner conduit extending about an area to be shielded from radiation, wherein the at least one first coil is disposed within the first inner conduit so as to also extend within the first inner conduit about the area to be shielded from radiation;providing a first outer conduit extending about the area to be shielded from radiation, wherein the first inner conduit is disposed within the first outer conduit;disposing a first cryogen liquid within the first inner conduit along with the at least one first coil;disposing a second cryogen liquid, different than the first cryogen liquid, within the first outer conduit, wherein the first cryogen liquid has a lower boiling point than the second cryogen liquid;providing thermal insulation surrounding the first inner conduit and positioned between the first inner conduit and the first outer conduit;providing at least one second coil comprised of a superconductive material;providing a second inner conduit and a second outer conduit extending about the area to be shielded from radiation and also extending about the first inner conduit and the first outer conduit, wherein the at least one second coil is disposed within the second inner conduit so as to extend within the second inner conduit about the area to be shielded from radiation, and wherein the second inner conduit is disposed within the second outer conduit; anddisposing first and third cryogen liquids within the second inner conduit and the second outer conduit, respectively, wherein the third cryogen liquid is different than the first and second cryogen liquids. 8. A method according to claim 7 wherein the first cryogen liquid comprises liquid helium and the second cryogen liquid comprises one of liquid oxygen, liquid nitrogen or liquid hydrogen. 9. A method according to claim 8 further comprisingproviding thermal insulation surrounding the second inner conduit and positioned between the second inner conduit and the second outer conduit. 10. A method according to claim 9 wherein the second cryogen liquid comprises liquid hydrogen and the third cryogen liquid comprises liquid oxygen, and wherein the radiation shield device further comprises a fuel cell configured to receive boil off of the second and third cryogen liquids. 11. A method according to claim 9 wherein the at least one first coil is spaced apart from the at least one second coil. 12. A method according to claim 7 further comprising providing a first intermediate conduit extending about the area to be shielded from radiation, wherein the first inner conduit is disposed within the first intermediate conduit, and wherein the first intermediate conduit is disposed within the thermal insulation and the first outer conduit.