| 摘要 |
PROBLEM TO BE SOLVED: To provide a superconducting magnetic gradient levitation system capable of reducing a lateral guiding force to an appropriate level, not being too high relative to a levitation force. SOLUTION: A superconducting magnetic field generating coil 4 is not thermally connected to a magnetic shield 5, and they are separately cooled by a first refrigerator 3 and a second refrigerator 8, respectively. The superconducting magnetic field generating coil 4 is suspended on the way to a nominal magnetomotive force. However, in order to hold the magnetic shield 5 in a normal conductive state upto that stage, the capability of the second refrigerator 8 is adjusted to low so that the magnetic shield 5 does not come into a superconducting state. Inside the magnetic shield 5, excited magnetic flux penetrates. The freezing capability of the second refrigerator 8 is improved at this stage, to make the magnetic shield 5 shift into a superconducting state, so that the penetrating magnetic flux that enters the magnetic shield 5 is captured and held as it is. Then, the superconducting magnetic field generating coil 4 is excited up to a nominal magnetomotive force. COPYRIGHT: (C)2005,JPO&NCIPI |
