Linear motor with reduced cogging force

摘要

There is provided a linear motor in which the shape of magnetic pole surfaces of pole teeth located at both ends of a plurality of pole teeth can be easily formed to be suitable for reducing cogging force. Each of magnetic pole surfaces 19a of pole teeth 15A located at both ends of a plurality of pole teeth 15 is constituted by an arc-shaped curved surface so curved that a gap from a stator 1 increases with increasing distance from other adjacent pole tooth 15B. Through holes 23A and 23B that extend in the laminating direction of electromagnetic steel plates 10 are formed in the vicinity of the magnetic pole surfaces 19a of the pole teeth 15A. Inside the through holes 23A and 23B, magnetic pieces shorter than the thickness of the electromagnetic steel plates in their laminating direction are so arranged as to leave spaces at both ends of the through holes 23A and 23B.