Abstract: A coil-winding method comprises: winding first coil clockwise around first, counterclockwise around second, and clockwise around third swath along mandrel, hooks grouped into swaths; winding second coil clockwise around between first arid second hooks of first to between first and second hooks of second swath, counterclockwise around from between first and second hooks of second to between first and second hooks of third swath, clockwise around between first and second hooks of third to between first and second hooks of first swath; winding third coil clockwise around between second and third hooks of first to between second and third hooks of second swath, counterclockwise around from between second and third hooks of second to between second and third hooks of third swath, clockwise around between second and third hooks of third to between second and third hooks of first swath; and releasing wound coils.