METHOD FOR MANUFACTURING FIELD MAGNET

The present invention provides a method for manufacturing a field magnet with which the inner surface of a bonded magnet press-fitted in a yoke can have a predetermined level of accuracy irrespective of the accuracy of the outer circumferential surface of the yoke. The present invention is a method for manufacturing a field magnet configured such that a cylindrical bonded magnet (2) is fixed in a tubular yoke (1) composed of a magnetic material. The bonded magnet (2) is obtained by binding magnet particles with a thermosetting resin. Specifically, the method comprises: a softening step for reheating and softening the bonded magnet after thermal curing treatment; and a press-fitting step for fitting in the bonded magnet after the softening step from a tapered portion (114) on one end side of the yoke to press an outer circumferential surface (22b) of the bonded magnet against an inner surface (12a) of the yoke. The press-fitting step is performed by feeding the bonded magnet relatively into the yoke while allowing a relative posture variation between the bonded magnet and the yoke. This allows the inner surface of the bonded magnet to be remolded into a shape along the inner surface of the yoke and exhibit almost the same level of accuracy as that of the inner surface of the yoke.