Patent ID: 8288907
Filing Date: 2012-10-16
Classification: H02K

Abstract:
1. An electric motor comprising: a housing; a rotor rotatably mounted in the housing; n arc-shaped permanent magnets with a same polarity fixed at an inner surface of the housing; wherein portions of the housing are deformed inwardly to form n arc-shaped inner projecting parts, the permanent magnets and the inner projecting parts being alternately arranged in a circumferential direction about the rotor, the permanent magnets forming n magnet field poles at the permanent magnets and n induced field poles at the inner projecting parts whereby generating 2n magnetic circuits via the housing and the rotor, n being an integer greater than one, wherein the circumferential width of the magnet field poles is greater than the circumferential width of the induced field poles; and wherein arc inner surfaces of the permanent magnets face the rotor, arc outer surfaces of the permanent magnets are fixed to the inner surface of the housing, and the inner surface and the outer surface of each permanent magnet are non-concentric.