Patent ID: 8198760
Filing Date: 2012-06-12
Classification: H02K

Abstract:
1. A linear motor comprising: a stator; and a mover that reciprocates with respect to the stator, one of the stator and the mover comprising one or more permanent magnet arrays each including a plurality of permanent magnets arranged in an array in a motion direction in which the mover reciprocates, the plurality of permanent magnets being magnetized in a perpendicular direction perpendicular to the motion direction such that magnetic poles having different polarities alternately appear on magnetic pole surfaces of the plurality of permanent magnets in the motion direction, and the other of the stator and the mover comprising an armature including first and second magnetic pole portion arrays disposed on both sides of the permanent magnet array in the perpendicular direction and each including a plurality of magnetic pole portions facing the magnetic pole surfaces of the plurality of permanent magnets, and excitation windings for n phases that excite the plurality of magnetic pole portions forming the first and second magnetic pole portion arrays, n being an integer of three or more, wherein each of the excitation windings for n phases is hollow-structured by winding a winding conductor into a coil such that p magnetic pole portions of the magnetic pole portions included in the first magnetic pole portion array, p being an integer of 1 or more, and q magnetic pole portions of the magnetic pole portions included in the second magnetic pole portion array, q being an integer of 1 or more, are located in an internal space of the coil and are excited by each of the excitation windings; the p magnetic pole portions included in the first magnetic pole portion array are shifted with respect to the q magnetic pole portions included in the second magnetic pole portion array in the motion direction; and the excitation windings for n phases are excited with respective phases shifted from each other by an electrical angle of 360/n degrees.