| 摘要 |
PURPOSE:To obtain a reliable, safe and transportable high-temperature superconducting magnet by a method wherein a coil formed by winding a superconductor and a solid coolant with which this coil is impregnated or which surrounds this coil and which becomes a solid at a temperature at which this coil becomes superconducting are provided so that even the locally generated heat can be absorbed by the latent heat of fusion of the solid coolant. CONSTITUTION:If, for example, liquid nitrogen is filled into a coil container 2 and a small-sized freezer 6 is operated, the coil container 2 is cooled uniformly by a heat- diffusing plate 8 to be less than 60K although this value depends on a relationship between the capacity of the freezer and a quantity of penetration heat; a triple point of the nitrogen becomes less than 0.12P and 6.5K; a part of the nitrogen is solidified. However, the heat capacity of the superconducting coil container 2 is large, so the liquid nitrogen is not solidified easily. If the inside of the coil container is evacuated by using a vacuum evacuation device 7, a superconducting coil 3, the helium container 2 and nitrogen 5 become less than about 63K, and the liquid nitrogen 5 becomes solid nitrogen. After that, if the freezer 6 whose freezing capacity is larger than a total quantity of penetration heat decided by the heat conducted from a support part, the heat generated by the coil and the like is installed, the solid nitrogen is cooled and kept as it is. |
