To provide a demagnetization method and a demagnetizer of a new rotator capable of efficiently demagnetizing a permanent magnet used in a rotator at temperature close to a room temperature without heating.
A rotator 21 is arranged in the vicinity of a magnetic pole 15a of a superconducting bulk magnet 10a, the rotator 21 is rotated centered on the rotational axis thereof while exposing the rotator 21 to a magnetic field emitted by the superconducting bulk magnet 10a, and the rotator 21 is gradually separated from the magnetic pole 15a. Permanent magnets 20a, 20b, 20c, 20d used in the rotator 21 can be efficiently and evenly demagnetized by gradually reducing the strength of the magnetic field with the rotator 21 exposed thereto in accordance with separation from the magnetic pole 15a while changing the direction of the magnetic field with the rotator 21 exposed thereto in accordance with the rotation of the rotator 21.
KAWASAKI NOBUTAKA
UEHARA SHO
Tomoyuki Takahashi