Distorted field motors, which can also be called shaded pole motors, are considered to be one of the simplest and most cost-effective types of single-phase induction motors. From the constructive life point there are several types, one of the most common forms being that of protruding poles. Each of these poles should have a part, on average from 25% to 35% of the pole, is embraced by a shorted copper loop. The current induced in this loop will cause the flow through it to suffer a delay in relation to the flow of the part not embraced by it.
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The result of this process, similar to a rotating field that can move in the direction of the uncaged part to the embraced part of the pole, causing the torque to dye the nominal rotation, which will allow the motor to split the direction of rotation, depending on the side in which is
the embraced part of the pole. In this way the distorted field motor may have a single direction of rotation. This sense can even be reversed by changing the position of the rotor shaft tip relative to the stator.