The fan is a mechanical device employed to convert rotational mechanical energy, applied in its axes, in increasing air pressure. It was invented in the USA in 1882 by the American Schuyler S. Wheeler and the fan is the mechanism responsible for ventilating the electric motor 1 horsepower 56c frame. The entire engine is sized so that its nominal speed of rotation rotate the fan quickly so that the airflow through the fins of its casing on armored models or through its interior in open models is what is needed to cool it within the rated operating conditions of the engine.

The fan in the shielded models is protected by the baffle cover, and needs it for its correct operation. The material used to make the fan is plastic, but in applications of great chemical and / or mechanical aggressions, it is made of aluminum. For motors having a speed below the rated speed, it may be necessary to use forced ventilation kits, which keep the fan spinning fast even if the motor shaft is not. In such cases, the fan is independent of the motor shaft.