Abstract: A modular, expandable, low-weight electric motor has a cylindrical, non-magnetic casing formed in axially-aligned sections. The casing sections are releasably connected to define a unitary structure with a polygonal exterior surface and a circular interior surface. Separate U-shaped stator pole assemblies are releasably mounted against the exterior of the casing, each casing section carrying the poles associated with a different motor phase. The poles extend through apertures into the interior of the casing, and have active pole faces which are curved and substantially flush with the circular interior surface of the casing. A modular rotor is mounted in the interior of the casing and carries magnetic elements in axially spaced-apart sets corresponding to each motor phase. The active faces of the magnetic elements are curved and oriented in a cylindrical arrangement.

Abstract: Complementary laminations for a stator pole assembly and a cooperating rotor pole assembly of an electric motor or generator are produced simultaneously from a plate of magnetic material. The plate is stamped to produce an outer peripheral edge corresponding in shape to the exterior of an annular stator yoke and to produce a central aperture shaped to be received by an indexing element of an indexing table. The plate is then repeatedly indexed about its center in equal angular increments and a punch is displaced in a reciprocating rectilinear fashion synchronized with the indexing to punch a multiplicity of identical apertures equally-spaced circumferentially. The apertures are shaped to define internal edge surfaces in the plate corresponding in shape to radially inner surface of the stator yoke and to radially outer surfaces of a central hub of the rotor pole assembly and to define a multiplicity of identical radial webs.