| 摘要 |
PURPOSE:To enhance a temperature margin on the side of a high magnetic field without increasing a flow rate and a pressure loss by a method wherein, in a superconducting magnet of a force cooling type, an expansion mechanism is installed between the side of the high magnetic field and the side of a low magnetic filed in a cooling route. CONSTITUTION:A winding part composed of a conductor 2 on the side of a high magnetic field and of a conductor 3 on the side of a low magnetic field is housed inside a coil container 4; high-pressure and low-pressure supermagnetic-field pressure helium 5 as a coolant flows from the conductor 2 to 3 via an electric current lead 6 installed at the upper part of the container 4. The conductors 2 and 3 are connected electrically via a connection conductor 9; on the other band, the coolant flows from the conductor 2 to 3 via a cooling pipe 9 provided with an expansion mechanism 7. A pressure plate 10 used to fix the conductor 9 against an electromagnetic force is inserted into a connection part; it is covered with an outer coating which is not shown in the figure. Thereby, a temperature rise is relaxed in an part where a quantity of incoming heat is large by utilizing the Joule-Thomson effect by a drop in a pressure of the conductor, and a grating operation of the conductor is executed at the connection part so that a tolerance against a temperature margin cannot be damaged. |
