Patent ID: 8125116

Claim:
An alternator for vehicle, comprising: a stator that outputs a U-phase voltage, a V-phase voltage and a W-phase voltage; a rotor rotatably mounted further inward relative to the stator, that comprises a field coil and a rotor core; and a field current control circuit that controls a field current flowing through the field coil, wherein: the stator comprises a U-phase stator that outputs the U-phase voltage, a V-phase stator that outputs the V-phase voltage and a W-phase stator that outputs the W-phase voltage, with the U-phase stator, the V-phase stator and the W-phase stator disposed along a rotational axis of the rotor; the U-phase stator, the V-phase stator and the W-phase stator each comprise a phase stator coil wound along a circumferential direction and a phase stator core that forms a magnetic circuit on two outer sides of the phase stator coil along the axial direction and also on an outer circumferential side of the phase stator coil and comprises an even number of stator tabs disposed along the circumferential direction so as to alternately extend from one outer side along the rotational axis toward another outer side and extend from the other outer side toward the one outer side along the rotational axis; the rotor core forms a magnetic circuit on an inner side along a radius of the rotor winding and also on two outer sides of the rotor winding along the rotational axis and comprises an even number of rotor tabs disposed along the circumferential direction so as to alternately extend from one outer side toward another outer side along the rotational axis and extend from the other outer side toward the one outer side along the rotational axis; the rotor tabs each comprise a surface facing opposite the stator tabs at the U-phase stator, the V-phase stator and the W-phase stator, disposed along the rotational axis; the phase stator cores at the U-phase stator, the V-phase stator and the W-phase stator are each formed by laminating a plurality of sheets constituted of a magnetic material, wherein the stator tabs are formed by bending the laminated magnetic sheets so that the magnetic sheets in the stator tabs are layered one on top of another along a radial direction, and wherein each phase stator core is integrally formed to enclose an entire circumference of the phase stator coil; an outer circumferential portion of each phase stator core is formed by bending the magnetic sheets so that the magnetic sheets are layered one on top of another along the radial direction in the outer circumferential portion; a front end of each stator tab is narrower than a base portion of each stator tab; a clearance is formed or a nonmagnetic material is disposed between the phase stator core of each of the U-phase stator, the V-phase stator and the W-phase stator and the phase stator core belonging to an adjacent phase stator; and a rotor side surface of each stator tab is formed by layering the magnetic sheets one on top of another in the radial direction and said rotor side surface faces the rotor.