Ferrarisläufer

Parts of a Ferraris engine (36 V / 400 Hz three-phase): left: Ferraris (aluminum cylinder), top: stator with windings, right: inner part of the stator (magnetic package, magnetic back)

Ferrari rider is a design of the rotor of asynchronous motors, which is due to Galileo Ferraris.

Ferraris are usually made of aluminum, but they do not contain iron, as opposed to cage rotors. They have the shape of a thin disc, such as, for example, in electromechanical Ferraris counters, or a thin-walled cylinder, such as in high-dynamic servomotors for aircraft. The rotor moves in the magnetic rotating field due to the eddy currents induced therein and its magnetic fields. Its advantage is the extremely low moment of inertia (due to the aging of the iron) compared to cage rotors and the quieter running (due to its higher symmetry). Edit source text

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