Patent ID: 6020669
Filing Date: 2000-02-01
Classification: H02K

Abstract:
An alternator for a vehicle, comprising:a field rotor including a Lundel-type iron core and a field coil provided on the Lundel-type iron core, the Lundel-type iron core having a cylindrical portion, a yoke portion, and a claw-like magnetic pole portion being connected to the yoke portion and being formed so as to surround the field coil; anda stator located radially outward of the claw-like magnetic pole portion and opposed to the claw-like magnetic pole portion, the stator including a multiple-layer iron core;wherein a ratio L1/L2 of an axial direction length L2 of the multiple-layer iron core of the stator to an axial-direction length L2 of the Lundel-type iron core is in a range of 0.7 to 1.0,said Lundel-type iron core has said axial-direction length L2 at an inner circumference of said cylindrical portion of said Lundel-type iron core, and said Lundel-type iron core extends radially outward from said inner circumference of said cylindrical portion without ever having an axial-direction length greater than said length L2, anda ratio L1/L3 of the axial-direction length L1 of the multiple-layer iron core of the stator to an axial-direction length L3 of the cylindrical portion of the Lundel-type iron core is in a range of 1.25 to 1.75, and a ratio R2/R1 of an outside radius R2 of the cylindrical portion of the Lundel-type iron core to an outside radius R1 of the claw-like magnetic pole portion of the Lundel-type iron core is in a range of 0.54 to 0.60.