Patent ID: 7269890

Claim:
A method of making a coil for a slotless permanent magnet rotary electric machinery, the coil including a plurality of turns of a flat conductor having a rectangular cross section including a long side and short side, the turns being formed by winding the conductor in an edgewise fashion, comprising the steps of: wrapping a first wire having a circular cross section of a substantially same diameter as the length of the short side of the flat conductor and a second wire having a circular cross section of a larger diameter than the first wire around an elongated flat bar in a spiral fashion in such a manner that the first and second wires alternate along the length of the flat bar while closely contacting each other as seen in a longitudinal sectional view of the flat bar; removing the first wire from the flat bar; wrapping the flat conductor around the flat bar along a space created by removing the first wire with the long side of the flat conductor oriented perpendicularly with respect to the axial line of the flat bar; and removing the second wire from the flat bar.