| 摘要 |
PROBLEM TO BE SOLVED: To provide a zero boil-off helium cooling type superconducting magnet, including a pressure controller for generating an exact control signal for controlling the pressure of a helium container. SOLUTION: A superconducting magnet assembly 10 is provided with a pressure container 4 for housing liquid refrigerating agent 46 for making a magnet coil to an extremely low temperature, vacuum container 2 arranged in the surrounding of the pressure container to be separated from the pressure container, cryocooler 12, re-condenser 39 arranged in the space between the pressure container 4 and the vacuum container 2 are thermally connected with the cryocooler 12 for returning a refrigerating agent gas generated from the pressure container 4 to liquid, means 54 and 58 for returning the recondensed liquid refrigerating agent to the pressure container 4, and pressure control means 74 for control the pressure in the pressure container 4 to be made higher than the outside pressure of the pressure container 4. Then, the pressure control means 74 senses the temperature of a recondenser 39, in response to a temperature sensor 70 arranged outside the pressure container 4. |
