| 摘要 |
PURPOSE:To acquire a superconducting magnet of a high mechanical rigidity and short initial cooling period by using a forced cooling conductor on the high magnetic field side and an immersion cooling conductor on the low magnetic field side. CONSTITUTION:A high magnetic field at the center of a superconducting magnet 1 is wound by a forced cooling conductor 4 of cable-in-conduit type, and the low magnetic field around the outside is wound by an immersion cooling conductor 3. They are electrically connected at a connection 7, and set in a case 2 and provided with a lead wire 5 interposing an insulator 10. For precooling, refrigerant is supplied through a pipe 8 below the case and a cooling pipe 9 of the lead 5. When precooling is finished, the supply through the pipe 9 is stopped and liquid He 6 is put through the pipe 8 to immerse conductors 3 and 4. Then supercritical He 11 is supplied through the pipe 9 to cool the conductor 4 which is connected to the lead 5, and is liquefied through a nozzle 14 interposing a jacket 13 at the connection 7 then passes the channel of the conductor 3 and a spacer 12 for circulation. According to this constitution, the initial cooling time is shortened without decreasing the mechanical rigidity of the winding. |
