When the DC power is supplied to the armature winding through the brush, the N pole of the conductor can flow in the same direction through the current on the armature surface, and according to the left-hand rule, the conductor will receive a counterclockwise torque; the surface of the armature under the S pole The conductor also flows current in the same direction, and according to the left-hand rule, the conductor will receive a counterclockwise torque.In this way, the entire armature winding, that is, the rotor, will rotate counterclockwise, and the input DC electric energy will be converted into mechanical energy output on the rotor shaft.