Patent ID: 8049382

Claim:
A brushless motor comprising: a stator including: a stator core having: an annular yoke; outer teeth projecting outward from the annular yoke; inner teeth projecting inward from the annular yoke; and a stator winding wound on the stator core; a rotor including: an inside rotor confronting the inner teeth and having a rotor-magnet; an outside rotor confronting the outer teeth and having a rotor-magnet; and a magnetism sensing device sensing a leakage magnetic flux leaking from the rotor magnet of the outside rotor, and placed at an identical angular position to a centerline between two adjacent outer teeth, wherein an axial distance between the rotor-magnet of the outside rotor and the magnetism sensing device is less than an axial distance between a rotor core of the outside rotor and the magnetism sensing device or an axial distance between the stator core and the magnetism sensing device.