Patent ID: 8552612
Filing Date: 2013-10-08
Classification: H02K,Y10T

Abstract:
1. A stator core including laminated stator core sheets, each of the stator core sheets punched out from a magnetic metal sheet, a central portion of the magnetic metal sheet previously punched out to form a rotor core sheet, the stator core sheet having a ring-shaped yoke piece and magnetic pole pieces formed radially inside the yoke piece, each of the magnetic pole pieces having a straight piece and a magnetic pole teeth piece formed radially inside the straight piece, the stator core comprising: a thin section formed in each of the straight pieces, the thin section formed by pressing one portion of the magnetic pole piece from both sides in a thickness direction, forming grooves having the same rectangular cross-sectional shape at both sides in a thickness direction of the thin section, depths of the grooves being within a range of 2-20% of a thickness of the magnetic pole piece, and radially-inwardly elongating the magnetic pole piece.