Patent ID: 6426576
Filing Date: 2002-07-30
Classification: H02K

Abstract:
A rotor for an electric machine, said rotor comprising:a shaft made in a single piece of nonmagnetic material for mounting the rotor for rotation about an axis, said shaft, seen in section perpendicular to the axis of rotation, having a convex polygonal cross section containing plane faces separated by edges; an assembly which includes a plurality of pole pieces and permanent magnets carried by the shaft, the pole pieces extending the entire radial height between the shaft and an air gap and defining chambers between them, said chambers accommodating the full length of said permanent magnets, each permanent magnet being in direct contact with one of said plane faces of said nonmagnetic shaft, and each pole piece, seen in section perpendicular to the axis of rotation, being located between adjacent magnets and having substantially radially extending sides opposite to said adjacent magnets and a radially inner end defining a reentrant angle which centers the pole piece on the opposite edge of the nonmagnetic shaft; a lateral flange at each axial end of the shaft; and tie rods connecting the flanges and passing through each pole piece mounting each pole piece between the lateral flanges.