SGM-01B314S Yaskawa 100w Power Supply Electric Servo Motor Module

By the attraction of opposite poles and repulsion of like poles, a torque then acts on the rotor and makes it turn. This torque is at a maximum
when the axis between the poles of the rotor is perpendicular to the axis of the poles of the stator.

As soon the rotor begins to turn, the fixed brushes make and break contact with the rotating commutator segments in turn.

The rotor coils are then energised and de-energised in such a way that as the rotor turns, the axis of a new pole of the rotor is always perpendicular to that of the stator. Because of the way the commutator is arranged, the rotor is in constant motion, no matter what its position. Fluctuation of the resultant torque is reduced by increasing the number of commutator segments, thereby giving smoother rotation.

By reversing the power supply to the motor, the current in the rotor coils, and therefore the north and south poles, is reversed. The torque which acts on the rotor is thus reversed and the motor changes its direction of rotation. By its very nature, the D.C. motor is a motor with a reversible
direction of rotation.