Patent ID: 7342333
Filing Date: 2008-03-11
Classification: H02K

Abstract:
1. An outer rotor type multi-pole generator comprising a stator mounted on a stationary support, and a rotor formed by fixedly attaching a magnet to the inner periphery of a bottomed cylindrical rotor yoke that is coaxially fixed to an end of a drive shaft rotatably supported by the stationary support and that coaxially covers the stator, cooling air being made to flow within a stationary casing covering the stator and the rotor, wherein a plurality of radially extending vanes are integrally provided in a closed end of the rotor yoke, and a plurality of intake holes positioned between the vanes are formed in the closed end of the rotor yoke, and wherein the rotor yoke comprises an end wall member and a cylindrical member, the cylindrical member being made of steel and the end wall member being made of an aluminum alloy so as to integrally have a disk portion having a central part thereof fixed to the end of the drive shaft, a ring portion coaxially surrounding the disk portion, and the plurality of vanes providing a connection between the disk portion and the ring portion, and the cylindrical member being formed in a cylindrical shape coaxially covering the stator and having one end thereof fixed to the ring portion, wherein projections are provided on an end face of the ring portion, the proiections being inserted into engagement holes provided in a collar portion of the cylindrical member, and a portion of each of the proiections projecting from the corresponding engagement hole being upset so as to engage with the collar.