Patent ID: 9621000
Date: 2017-04-11
CPC Classifications: H02K,Y10T

Claim:
1. A permanent magnet rotor assembly having a longitudinal axis of rotation X′-X, first and second ends and at least two poles, comprising a cylindrically shaped shaft having an outer surface extending in the direction of the longitudinal axis X′-X, a plurality of permanent magnets constituting portions of annular segments and extending in the direction of the longitudinal axis X-X′ and an outer retaining cylindrical sleeve surrounding the plurality of permanent magnets, comprising: a cylindrical magnet housing mounted on the cylindrically shaped shaft for supporting the plurality of permanent magnets, the cylindrical magnet housing being formed of a magnetic material and in that the retaining cylindrical sleeve is preloaded by a resultant interference fit IF2 which is defined by the following formula: where ΦY is an external diameter of the plurality of permanent magnets, ΦX is an internal diameter of the cylindrical magnet housing, and IF1 is a primary interference fit between an external diameter of the cylindrically shaped shaft and the internal diameter of the cylindrical magnet housing.