Patent ID: 7436095

Claim:
A rotor for an electric machine, comprising: a rotor core constructed of magnetically-permeable material; and a permanent-magnet cluster creating a first magnetic pole of the rotor, the permanent-magnet cluster being composed of permanent magnets mounted to the rotor core, including a first permanent magnet having substantially radial magnetic polarity, a second permanent magnet having a first end disposed adjacent a first end of the first permanent magnet with a first portion of the rotor core disposed therebetween, and a third permanent magnet having a first end disposed adjacent a second end of the first permanent magnet with a second portion of the rotor core disposed therebetween; and a fourth permanent magnet having substantially radial magnetic polarity forming at least a portion of an outer perimeter of the rotor, the fourth permanent magnet being disposed radially outward of at least a portion of at least one of the first permanent magnet, the second permanent magnet, and the third permanent magnet, wherein the first permanent magnet and the fourth permanent magnet cooperate to generate radial magnetic flux.