PURPOSE: To facilitate the repair or replacement of a permanent current switch for enhancing the stability of the same by having the permanent current switch in a cryostat different from that for a superconductive coil.
CONSTITUTION: A permanent current switch 4 is contained in a low temperature vessel 5 for the permanent current switch 4 while the vessel 5 is contained in a vacuum vessel 8 for the permanent current switch 4. Thus, the permanent current switch 4 is contained in a different cryostat from that for a superconductive coil so that the permanent current switch 4 may be easily repaired or replaced. Besides, the superconductive coil and the permanent current switch 4 can be arranged at a long interval so that the permanent current switch 4 may be provided on a position in a magnetic field not exceeding 1 (T). Through these procedures, the permanent current switch 4 can be stabilized.
SONOBE TADASHI
WATANABE HIROYUKI
