Patent ID: 7759837

Claim:
A rotating electrical machine, comprising: a field magnet disposed around a rotational axis; a rotor core disposed so as to hold the field magnet, wherein the rotor core comprises field magnetic poles located at positions facing opposite stator claw poles at a stator core; a stator coil wound around in an annular pattern on an outer circumferential side of a rotor; and a stator core that comprises stator claw poles located at a position facing opposite the rotor and alternately extending from two sides taken along an axial direction and is disposed so as to surround the stator coil, wherein: a reactance to be guided to the stator coil is reduced by keeping down a quantity of an interlinking magnetic flux traveling from front ends of the stator claw poles through a recessed portion, the interlinking magnetic flux being generated with an electric current flowing through the stator coil; the distance between the stator core claw poles and the recessed portion is so arranged that a magnetic reluctance manifesting between front ends of the stator claw poles and the recessed portion facing opposite centers of the stator claw poles along the circumferential direction is set greater than the magnetic reluctance between the front ends of the claw poles and the stator core enclosing member facing opposite the front ends; and a distance between front ends of the stator core claw poles and a center of the recessed portion facing opposite centers of the stator claw poles along the circumferential direction is taken 0.8-2.0 times as large as a distance between front ends of the stator core claw poles and the recessed portion facing opposite centers of the stator claw poles along the circumferential direction.