Patent ID: 7057327

Claim:
A vehicular alternator comprising a rotor and a stator constituted by coiling stator windings over a stator core, wherein: said rotor comprises i) a pair of claw-type magnetic poles which are arranged in an opposed relation, and each of which has a plurality of claws that are cantilevered at a proximal end thereof and extend axially to a distal end opposite said proximal end, ii) permanent magnets having rectangular lateral surfaces which face in a circumferential direction of the rotor and form magnetic pole surfaces that are disposed between and in contact with opposing lateral surfaces of adjacent claws of said pair of claw-type magnetic poles, and iii) field windings coiled radially inward of said plurality of claws; the opposing lateral surfaces of said claws adjacent said permanent magnets are formed into substantially the same rectangular shape as the magnetic pole surfaces with which they are in contact, such that said lateral surfaces of said claws are in contact with the whole of the rectangular lateral magnetic pole surfaces of said permanent magnets; and each of said claws has, in a circumferentially central portion thereof, a radial thickness that is tapered along an axial direction, being thicker at said proximal end than at said distal end thereof.