| 摘要 |
PURPOSE: To impart strength for withstanding against extreme fluctuations of electromagnetic and thermal forces by a method, wherein a plurality of annular cancellation coils are arranged concentrically around a main magnet coil by using a support structure which extends between a ring shape drum and the cancellation coils. CONSTITUTION: A support structure for cancellation magnet coils 8 and 9 includes a plurality of pillars or plates 12, which extend from a drum 1 or a band 13 around the drum outwards with a predetermined angle to cylindrical cancellation coil supporters 18 and 19. Further, spacer rods 14 are laid extending in the axial direction mutually between the cancellation coil supporters 18 and 19. A toroidal plane which has an approximate isosceles trapezoidal cross section in composed of the pillars 12, the drum 1 and the spacer rods 14. With this constitution, the withstanding strength against extreme electromagnetic and thermal forces and loads can be obtained, while the necessary concentricity and uniformity of the magnetic field are maintained. |
