| 摘要 |
PURPOSE:To obtain a compact cryostat by absorbing the thermal contraction of a cryogenic tank with a spring having small spring constant, and supporting a large external force after thermal contraction by a spring having a large spring constant. CONSTITUTION:An interval G1 between a flange 8 and the second spring retainer 19 is regulated by a clamping bolt 20, and an initial load is applied to the second spring 18. Then, the position of a superconductive coil 2 is regulated by a regulating nut 9. Then, a regulating ring nut 21 is turned, the interval G2 between the first retainer 16 and a nut 21 is opened in the thermal contraction of a helium tank 1. The first spring 17 absorbs the thermal contraction so that tension is not applied to a thermal insulation supporting force unit 5 in case that the tank 1 is thermally contracted. When the tank 1 is thermally contracted, the interval G2 is eliminated, and a force having large eccentric electromagnetic force is supported by the spring 18 having large spring constant, necessary minimum load is merely applied to the unit 5, and the strengths of the thermal insulating force column, the cyrogenic tank and a vacuum tank can be minimized. |
