Patent ID: 6472793
Filing Date: 2002-10-29
Classification: H02K

Abstract:
An alternator for a vehicle, comprising:a stator including a stator iron core having a plurality of teeth extending radially inwardly and arranged at an interval in a circumferential direction to define slots between said plurality of teeth, and a stator winding disposed in said slots; and a rotor including a pair of pole core members each of which has a plurality of tapered claw-like magnetic poles formed on its outer-diameter side at a predetermined pitch in a circumferential direction, and located inside said stator so that a constant air gap &dgr; is defined between outermost-diameter surfaces of said claw-like magnetic poles and tip portions of said teeth, wherein each of said claw-like magnetic poles includes an air gap enlargement surface formed in at least a portion of each of both circumferential-direction side portions on an outer-diameter side to provide an air gap larger than said air gap &dgr; with respect to said tip portion of each of said teeth, and when a circumferential-direction central position between the adjacent claw-like magnetic poles is aligned with a circumferential-direction central position of said tip portion of said tooth viewed from a radial direction, said tip portion of said tooth does not overlap with said outermost-diameter surface of each of the adjacent claw-like magnetic poles, and said tip portion overlaps with at least a portion of said air gap enlargement surface of each of the adjacent claw-like magnetic poles, and a circumferential-direction distance &tgr; between said outermost-diameter surface and said tip portion of said tooth is set to be 0