Preliminary forming method for polygon coil and forming method for annular winding coil having meandering portion using pre-formed polygon coil

摘要

PPROBLEM TO BE SOLVED: To propose a technique wherein corrugated protrusions will not become a drum shape, when a meandering loop winding coil is formed by molding. PSOLUTION: The preformed polygonal coil of the invention is used to form a loop winding coil having multiple meandering portions disposed in the stator of an electric motor. These meandering portions are formed, while the coil diameter of a loop winding coil before forming is reduced by cooperation between a first mold unit and a second mold unit. The polygonal coil is formed in the shape of a substantially polygonal ring to include: a vertex portion whose curvature radius is substantially equal to the curvature radius of the non-meandering portion of the loop winding coil having the meandering portions as the target shape of forming and a straight side portion. PCOPYRIGHT: (C)2009,JPO&INPIT