Unipolarmaschinen

1,133,724. Homopolar electrical machines having superconductive windings. INTERNATIONAL RESEARCH & DEVELOPMENT CO. Ltd. 24 Feb., 1966 [9 March, 1965], No. 10062/65. Heading H2A. A homopolar dynamo-electric machine, i.e. motor, generator or electromagnetic brake, includes a superconducting field coil 26 enclosed in a cryostat 27 surrounding a rotor 11 having at least one electric current conducting path between which and an external circuit the current is transferred by a means. Such means may be of the liquid, e.g. mercury contact type, but as shown comprises brushes 22 biased by constant force springs 24 to engage cylindrical flanges 18 . . . 21 of conducting discs 15 16 insulatedly carried by the rotor 11. The stator includes ferromagnetic polepieces 28 held apart by magnetic or otherwise spacers 29, and a magnetic screening superconducting coil 30 in a cryostat 31. In Fig. 1, not shown, the disc spacers (5) form fan vanes to circulate cooling air, the rotor brushes (7a), (8a) through which D.C. is passed are ring shaped, and the D.C. in the field coil creates a magnetic flux which where passing through the discs is parallel with the rotary axis. The rotor alternatively may comprise one or more drums, and be wholly an electrically conductive body. Used as a motor, the machine may be supplied by a M.H.D. generator.