Abstract: A dynamo-electric machine which can function as a motor or a generator. The machine comprising a stator and an armature, and switching of the armature coils is accomplished by means of a switching control assembly which is mounted to, and rotates with, the armature. In operation as a motor, direct current is supplied through brushes to slip rings that rotate with the armature, and the DC current supplied is first passed through switch means in the control assembly to deliver the current in properly timed relationship with respect to the rotation of the rotor. This provides greater versatility in the operation of the motor/generator and eliminates many of the problems related to the use of conventional brush commutation commonly used in present day DC motors and generators.