Abstract: A hybrid permanent magnet dc motor includes three sets of permanent magnets supported by the rotor and three sets of corresponding stators fastened to the surrounding frame. One set of magnets operates across a radial gap with a surrounding radial gap stator, and the other two sets of magnets operate off the respective ends of the rotor across respective axial gaps.

Abstract: An AC generator has a rotor with permanent magnets disposed between claw poles. The rotor has Lundell-type pole cores having a boss portion where a field coil is wound and claw poles. The permanent magnets are sintered ferrite magnets and disposed between opposite side surfaces of the adjacent claw poles and magnetized to have the same magnetic pole as the claw pole adjacent thereto. A ratio between the cross-sectional area per pole of the magnetic path of the boss portion and peripheral surface area of the claw poles facing the teeth of the stator core is designed to be between 70% to 120%.

Abstract: A bearing installation for a Floppy Disk Driver motor which is simple in structure and high in accuracy of a rotating action of a rotary shaft, thus hardly impairing the read and write characteristics of a Floppy Disk Driver device.

Abstract: A brush system for providing an electric connection to a rotating commutator wheel of an electric machine is disclosed. The brush system has a switched brush selectively switchable between an engaged position and a disengaged position and a switch connected to the switched brush and formed of a shape-memory-alloy. The switch attains an extended state at a first temperature and attaining a retracted state at a second temperature, for switching the switched brush alternately to the respective engaged position and the respective disengaged position. The switch includes a temperature conditioner for varying a temperature at the switch between the first temperature and the second temperature. The temperature condition may be an electric network wherein the internal resistance of the switch allows for heating of the switch to the second temperature.