Superconducting magnet and MRI apparatus, NMR apparatus

摘要

Provided superconducting magnet allowing the temperature of the permanent current switch to be quickly lowered and the excitation time of the superconducting magnet to be shortened, an MRI apparatus and an NMR apparatus having the superconducting magnet. A superconducting magnet structure is disclosed in which a superconducting coil 1 is connected to a second stage 22 of a refrigerating unit 2 through a low-temperature-side highly thermal conductor 3 and a permanent current switch 4 covered by a highly thermal conductor 5 is connected to a second stage 22 of the refrigerating unit 2 through a heat insulator 6 and a low-temperature-side highly thermal conductor 3. Gas is supplied from a gas bottle 8 disposed outside a vacuum vessel 16 to a condenser 11 in a thermal shield 12. In addition, a first pipe 14 that supplies condensate liquid to a liquid storage chamber 7 is provided. The liquid storage chamber 7 is disposed at an upper portion of the permanent current switch 4. A check valve 13 is connected to the first pipe 14.