H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
H02K—DYNAMO-ELECTRIC MACHINES
H02K23/00—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors
H02K23/40—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors characterised by the arrangement of the magnet circuits
H02K23/42—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors characterised by the arrangement of the magnet circuits having split poles, i.e. zones for varying reluctance by gaps in poles or by poles with different spacing of the air gap