| 摘要 |
PURPOSE:To reduce the intrusion of heat from a current lead for connecting a superconducting coil electrically with a power supply and to reduce thermal loss of a connecting lead including the current lead. CONSTITUTION:A conductor comprising the series connection of a first oxide superconductor 302 to be connected with a lead of a superconducting coil, a first connecting piece 303, a second oxide superconductor 304, a second connecting piece 305, and a good conductor 306 is contained in a lead piping 301. Liquid nitrogen N1 is injected from a liquid nitrogen piping 310 to the gap between the second oxide superconductor 304 and the lead piping 301 in the vicinity of the first connecting piece 303 which partitions the inner space of the lead piping 301 hermetically. The first oxide superconductor 302 is cooled with helium gas whereas the second oxide superconductor 304 is cooled with liquid nitrogen N1 and nitrogen gas N2, and the normal temperature terminal of current lead is connected directly with a power supply connection lead and the long distance between the superconducting unit and the power supply is connected principally by a superconductor. |
