Abstract: A solenoid coil generates a magnetic field within its bore when an electrical current is made to flow therethrough. A disc type rotor carrying thereon an armature coil is arranged in the bore along with a superconductor shield partly covering the disc type rotor. The magnetic field generated by the solenoid coil cannot pass through the superconductor shield and therefore detours around it and passes through an area devoid of the superconductor shield. The superconductor shield is also used to direct the electrical current flowing through the portions of the armature coil not covered by the superconductor shield, either from the periphery toward the center of the disc type rotor or conversely from the center toward the periphery thereof. With this arrangement, the Lorentz force applied to the radial electrical current is made to become a one-directional rotary force that drives the disc type rotor to rotate.

Abstract: A homopolar dynamoelectric machine comprises a solenoid coil for generating a magnetic field, having a cavity formed around an axis thereof. A rotating shaft, which constitutes a rotor, is rotatably provided in the cavity about the axis. A circular plate, which also constitutes the rotor, is integrally fixed on the shaft. A rotating body is rotatably supported by the plate about an axis of the shaft. A first electric current path, through which an electric current can pass from a proximal portion to a distal portion of the rotor, is integrally provided in, for example, the plate. A second electric current path, through which an electric current can pass from a distal portion to a proximal portion of the rotor, is integrally provided in the rotating body. The first and second paths are electrically connected in series, and are adapted to be electrically connected to a power supply in order to supply a direct current to these paths.