| 摘要 |
PURPOSE:To obtain less thermal invasion from current leads and to eliminate the possibility of reduction in liquid helium by associating an opposite flow heat exchanger with current leads, and providing a liquid helium storage tank connected to the exchanger. CONSTITUTION:A lead conduction unit is formed to form a zigzag passage of helium gas with a disturbing plate 16 made of copper by a lead body 19 via fine copper wirings through an electric insulator 15 in a current lead outer cylinder 14 which passes through the walls of a helium vessel 4 and a vacuum adiabatic vessel 13 for surrounding the vessel 4 for containing a superconductive coil. A copper header 18 for introducing 4.2 deg.K liquid helium from a helium tank 6 is provided, an opposite flow heat exchanger 20 is disposed at the vessel 4 side, 4.2 deg.K liquid helium is flowed in the tube, pressure-reduced 4.2 deg.K or lower evaporated helium gas 21 is flowed out of the tube to oppositely heat exchange therebetween. |
