| 摘要 |
PURPOSE:To recover helium gas being yielded when liquid is abnormally evaporated in a cryostat and to miniaturize a heater and a gas bag, by providing an expanding valve and a condensation heat exchanger in the cryostat. CONSTITUTION:The cryostat 1, wherein the liquid He 2 is enclosed and a superconductive magnet 3 is immersed therein, is connected to a heater 4 in series. A compressor 6 and gas cylinders 7 are connected in series. A gas bag 5 is branched from the intermediate point between the heater 4 and the compressor 6. In this way, the magnet is cooled to about 4.2K by the liquid He 2, and the evaporated He is heated by the heater from the low temperature to the normal temperature and stored in the gas bag. When the bag is filled up, the gas is compressed by the compressor an stored in the cylinders. In this constitution, a pressure keeping expansion valve 8 and the condensation heat exchanger 9 are added in the cryostat 1. About one half of the abnormally evaporated He gas is recovered to the liquid He again and stored in the lower part of the cryostat 1. |
