| 摘要 |
In the present invention, each tooth (22) has a tooth body part (24) and a tooth tip part (25). A pair of slant parts (26) project from both circumferential sides of the tooth tip part (25). A tip surface (27) is formed on the inner diameter-side end surface of the tooth tip part (25) so as to face a magnet (15) across an air gap (g). A recessed groove part (28) extending in an axial direction is disposed at the center of the tip surface (27). The depth (d) of the groove part (28) is set in the range of 0<d≤(Lx-Rt)/3, and the width (Wg) is set in the range of Wt>Wg≥Wt/2 (Lx: distance from the center of a rotor to a tooth-slant intersection (X), which is the intersection of an extended line (P) from a circumferential side surface of the tooth body and an extended line (Q) from the slant surface of the slant part; Rt: radius of the inner diameter of the tooth tip surface; Wt: width of the tooth body). |
