Compound induction electric rotating machine

Claim 1

A dynamoelectric machine comprising: a frame; a rotatable shaft supported by said frame; a cylindrical rotor mounted coaxially on said shaft defining two axial end surfaces each substantially in a plane normal to said shaft and a cylindrical circumferential surface coaxial with said shaft between said axial end surfaces, said rotor being provided with a plurality of rotor coil winding grooves which are generally parallel to said shaft and substantially uniformly spaced from each other about said circumferential surface to define a predetermined number of magnetic poles; a distributed armature winding having axial portions parallel to said shaft and received within said rotor grooves and radial portions in the region of said end surfaces and extending between substantially diametrically opposite grooves with respect to said shaft; said winding radial portions at each axial end surface of said rotor creating a build-up of overlapping windings which is minimum at said circumferential surface and gradually increases to a maximum in the region of said shaft, said build-up generally defining a conical convex surface; magnetic field producing means mounted on said frame in proximity to said rotor cylindrical circumferential surface and extending axially beyond at least one of said rotor axial end surfaces; and a plurality of rotor extensions projecting axially at said at least one of said rotor axial end surfaces to thereby position said rotor extensions and said portion of said magnetic field producing means in proximity and in magnetic coupling relationship to one another and said extensions at least partially axially overlapping said build-up of winding radial portions, whereby magnetic fields coupled into said rotor extensions by said magnetic field producing means is induced into said cylindrical rotor and to both said axial and radial portions of said distributed armature.