Patent ID: 8567043

Claim:
A method of forming a stator or rotor of an electric motor or generator, the method comprising: forming a core of the stator or rotor, the core being formed of ferromagnetic material and having a circular body portion and a plurality of teeth, the circular body portion defining a central axis, the axis defining radial and circumferential directions, the teeth being arranged circumferentially about the axis and extending radially outward from the circular body portion, the circular body portion comprises a plurality of interior surfaces that face toward the axis, a slit extends between a pair of the interior surfaces and extends radially outward partially through the circular body portion, the slit having a pair of opposing faces; welding at least portions of the opposing faces of the slit to each other in a manner limiting relative movement between the pair of the interior surfaces and increasing the stiffness of the core, wherein the core comprises a plurality of said slits and each of the slits extends between a pair of the interior surfaces and extends radially outward partially through the circular body portion, each of the slits has a pair of opposing faces, and the step of welding comprises creating an annular bead weld that extends circumferentially around the axis and that joins at least portions of the opposing faces of each of the slits to each other.