Patent ID: 6107719
Filing Date: 2000-08-22
Classification: H02K

Abstract:
A rotor for an automotive alternator comprising:a pair of field cores each having a cylindrical base portion and a plurality of claw-shaped magnetic poles projecting from outer circumferential edges of said base portions, said field cores being secured to a rotating shaft and facing each other such that end surfaces of said base portions are in close contact with each other and said claw-shaped magnetic poles intermesh with each other;a cylindrical bobbin having a cylindrical portion, a pair of first and second annular flange portions projecting perpendicularly from both ends of said cylindrical portion, a recessed groove disposed in an inner wall of said first flange portion at an angle to a radial direction of said cylindrical portion, and an anchor portion disposed on an outer circumferential portion of said first flange portion in close proximity to an outer circumferential end of said recessed groove, said bobbin being fitted over said base portions of said pair of field cores; anda field winding wound a predetermined number of turns into multiple layers on said cylindrical portion of said bobbin,wherein said field winding has a flat shape, the starting end of said field winding being wound around said anchor portion and housed in said recessed groove, then drawn from an inner circumferential end of said recessed groove onto the outer circumferential surface of said cylindrical portion of said bobbin, and additionally taken across said outer circumferential surface of said cylindrical portion of said bobbin from said first flange portion to said second flange portion, and thereafter being wound onto said outer circumferential surface of said cylindrical portion of said bobbin at an angle relative to a plane which perpendicularly intersects the axial center of said bobbin.