Cantilevered Rotor Magnet Support

A multilayer laminated rotor mountable on a shaft for rotation relative to a stator of a rotary electric machine arrangement has a plurality of laminas joined together to form the rotor and voids for receiving magnets. The rotor has an annular section, extending between a shaft opening for receiving the shaft and a radially outer circumferential rotor surface, which includes an undulating series of the voids in void groups extending from the radially outer circumferential rotor surface inwardly toward the shaft opening and then back toward the radially outer circumferential rotor surface. A pair of distal voids in each void group, together with distal voids of adjacent void groups, define gaps separating adjacent arc sections of the radially outer circumferential rotor surface. Such an arrangement forces the structural support to be cantilevered, improving rotor integrity, and, due to a reduction in magnetic leakage pathways, provides improved electrical performance.