Patent ID: 8569916

Claim:
An electrical machine apparatus 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 such that magnetic poles having different polarities appear on two magnetic pole surfaces of each permanent magnet that are opposite each other in a perpendicular direction perpendicular to the motion direction, and the plurality of permanent magnets being disposed such that magnetic poles having different polarities alternately appear on magnetic pole surfaces of the permanent magnets in the permanent magnet array along the motion direction, and the other of the stator and the mover comprising: one or more armature units each including: a first magnetic pole portion assembly including two or more magnetic pole portions facing the magnetic pole surfaces of the permanent magnet array and disposed in the perpendicular direction and on one side of the permanent magnet array; a second magnetic pole portion assembly including one or more magnetic pole portions facing the magnetic pole surfaces of the permanent magnet array and disposed in the perpendicular direction and on the other side of the permanent magnet array, the one or more magnetic pole portions included in the second magnetic pole portion assembly being shifted in the motion direction with respect to the two or more magnetic pole portions included in the first magnetic pole portion assembly; and a single phase winding having a hollow structure formed by winding a winding conductor into a coil around a centerline of winding such that the two or more magnetic pole portions included in the first magnetic pole portion assembly, the one or more magnetic pole portions included in the second magnetic pole portion assembly, and a part of one permanent magnet array are located in an internal space of the winding and that the centerline of winding extends in the motion direction in which the mover reciprocates; and one or more yoke members disposed such that magnetic flux alternately flowing through the permanent magnets in the one or more permanent magnet arrays that are positioned in the internal space of the winding and the first and second magnetic pole portion assemblies forms a closed magnetic path and that the magnetic flux flows through two magnetic surfaces of each permanent magnet in the internal space of the winding, where one of the magnetic pole portions of the first and second magnetic pole portion assemblies are completely separated from the one or more yoke members so that the one of the magnetic pole portions does not directly contact the one or more yoke members.