Patent ID: 8829756

Claim:
A method for making a poly-phase field winding for a slotless stator including a plurality of coil windings arranged in at least a first coil group and a second coil group, said method comprising: forming the first coil group by winding an insulated wire for each coil winding in a first direction around a mandrel such that each turn of the wire is adjacent a next turn of the wire, wherein each coil winding in the first coil group has substantially the same coil width when completed and a separation between adjacent coil windings in the first coil group is a distance substantially equal to the width of one of the completed windings; after forming the first coil group, axially shifting along the mandrel the insulated wire from a trailing edge of each coil winding a distance substantially equal to the number of coil groups multiplied by the number of coil windings minus one times the width of one of the completed windings to position the wires at a leading edge of each of coil winding in the second coil group; forming the second coil group by winding the insulated wire for each coil winding in the same first direction around the mandrel such that each turn of the wire is adjacent a next turn of the wire, wherein each coil winding in the second coil group and the first coil group has substantially the same coil width when completed and wherein a separation between adjacent coil windings in the second coil group is a distance substantially equal to the width of one of the completed windings; removing the mandrel from the wound first and second coil groups; collapsing the wound first coil group and the second coil group to a single layer web such that coil winding segments formed on a first side of the mandrel are interleaved with the coil winding segments formed on the opposite side of the mandrel, and wrapping the single layer web into a cylinder to form the field winding.