Abstract: A toroidal AC generator includes an outer casing and an annular stator core of ferromagnetic material which is encased in a hollow annular cover of plastics material and which is fixed to the casing between the discs of a twin disc rotor. Each rotor disc carries a circular array of alternately polarised permanent magnets which face the stator core. The hollow annular cover is a two-part moulding and is formed of radially inner and outer ring portions which are joined by circular arrays of radial ribs which extend across the opposed radial faces of the annular core and form open-ended radial passages for the electrical phase windings which are wound around the cover. The ribs project radially beyond the radially outer ring portion and form hooks around which a winding may be retained temporarily during winding.

Abstract: A toroidal AC generator includes an outer casing (11) and an annular stator core (33) of ferromagnetic material which is encased in a hollow annular cover (34) of plastics material and which is fixed to the casing (11) between the discs (14 and 15) of a twin disc rotor (10). Each rotor disc (14, 15) carries a circular array of alternately polarised permanent magnets (23 and 24) which face the stator core (33). The hollow annular cover (34) is a two-part moulding and is formed of radially inner and outer ring portions which are joined by circular arrays of radial ribs which extend across the opposed radial faces of the annular core (33) and form open-ended radial passages for the electrical phase windings which are wound around the cover (34). The ribs project radially beyond the radially outer ring portion and form hooks around which a winding may be retained temporarily during winding.