METHOD FOR MANUFACTURING FIELD MAGNET

An object is to provide a manufacturing method capable of producing, at low cost, a field magnet in which the inner surface of a bonded magnet press-fitted in a case satisfies a desired accuracy. The present invention provides a method for manufacturing a field magnet (F) formed such that a cylindrical bonded magnet (2) is fixed in an approximately bottomed tubular case (1). The bonded magnet is formed by binding magnet particles with a thermosetting resin. The method comprises: a softening step for reheating and softening the bonded magnet after thermal curing treatment; and a press-fitting step for press-fitting the softened bonded magnet into the case from an opening on one side of the case. The case has a cylindrical portion (11) and a lid portion (12) coupled to an other side of the cylindrical portion. The cylindrical portion has a fixing portion (113) for the bonded magnet. At least the fixing portion (113) is formed of a magnetic material. The press-fitting step includes feeding the bonded magnet relatively into the cylindrical portion while allowing a relative posture variation between the bonded magnet and the case. This makes it possible to stably feed even the softened bonded magnet into the case, and the inner surface of the bonded magnet has a similar accuracy to that of the inner surface of the case.