PURPOSE: To improve the assembling accuracy by securing a plurality of drive coils integrally through resin molding while simultaneously resin molding a housing integrally with the integrated drive coils.

CONSTITUTION: A plurality of drive coils 9 are secured integrally with a stator yoke 7 and a printed board 8 through insert resin molding, and a flat face facing with a magnet 4 is formed by means of a resin mold section 20 and the drive coils 9. At the same time, a housing 21 is resin molded integrally. By such arrangement, the face of the drive coil 9 facing with the magnet 4 can be made perpendicular to the axis of the housing 21 with high accuracy, and caulking work of the stator yoke 7 to the housing 21 can be eliminated. By such arrangement, assembling work is facilitated and the accuracy is improved.