Patent ID: 7119507
Filing Date: 2006-10-10
Classification: H02K

Abstract:
1. A brushless DC motor comprising: a stator; and a rotor comprising a plurality of permanent magnets each having a predetermined thickness and being mounted in an interior of the rotor, a plurality of flux bafflers made of non-magnetic sections, each of flux bafflers beginning from an edge section in circumferential direction of one of the permanent magnets, extending up to vicinity in a surface of the rotor, and having a length in a circumferential direction which is greater than a thickness of the permanent magnets, and a rib which is disposed between magnetic poles, the flux bafflers are configured and arranged such that an angle θ wherein, a frequency of vibration which is to be reduced is represented with f, a pole pair number is represented with Pn, an electrical frequency is represented with f