Patent ID: 6501205
Filing Date: 2002-12-31
Classification: H02K

Abstract:
An alternator comprising:a rotor for forming north-seeking (N) and south-seeking (S) poles about a rotational circumference; a stator comprising: a stator core disposed facing said rotor; and a polyphase stator winding installed in said stator core; and a bracket supporting said rotor and said stator, wherein said stator core comprises a laminated iron core formed with a number of slots extending axially at a predetermined pitch in a circumferential direction, said polyphase stator winding comprises a number of winding sub-portions in each which a long strand of wire is wound so as to alternately occupy an inner layer and an outer layer in a slot depth direction within said slots at intervals of a predetermined number of slots, said strand of wire folding back outside said slots at axial end surfaces of said stator core to form turn portions, and said turn portions align in a circumferential direction to constitute coil end groups at both axial end portions of said stator core, wherein said number of winding sub-portions are constructed with at least one winding assembly formed by simultaneously bending and folding a plurality of said strand of wires, wherein said winding assembly is constructed by arranging at one slot pitch offset the same number of wire-strand pairs as said predetermined number of slots, each of said wire-strand pairs constructed by arranging two strands of said strands of wire so that straight portions alternately overlap at a predetermined pitch, each of said strands of wire being formed into a pattern in which said straight portions are connected by turn portions so as to be arranged at a pitch of said predetermined number of slots and adjacent straight portions are offset by said turn portions so as to alternately occupy said inner layer and said outer layer in said slot depth direction, and by extending each end portion of said strands of wire on both sides of both ends of said winding assembly and arranging the same number of pairs of said overlapping straight portions as the number of said slots at said one slot pitch.