Abstract: In a three-phase four-pole armature winding of the double-layer lap type, three first pole windings of respective phases are dispersively arranged in first divided regions obtained by dividing all the slot region into three equal regions and three second pole windings of the respective phases following the respective first pole windings are dispersively arranged in second divided regions obtained by dividing all the slot region into three equally divided regions. Third and fourth pole windings are dispersively arranged in respective slot regions in the same manner. The first and second divided regions are circumferentially shifted from each other by an electrical angle of 180 degrees. Insertion of all the coils belonging to each of the first to fourth pole windings in all the phases is completed by one coil inserting operation of an automatic coil inserter.

Abstract: In a three-phase armature winding of the concentrically wound double-layer type, coil ends of three-phase first pole windings are distributed on an outermost circumference and coil ends of second and other pole windings are distributed on inner circumferences in turn in a first arrangement. In a second arrangement, coil sides of three-phase first pole windings and second pole windings paired with the first pole windings in a three-phase six-pole arrangement are laid in adjacent slots in sequence. This coil arrangement is applied to paired fifth and fourth pole windings.