Coil forming device and coil of a rotating electric device

A stator for a rotating electric device, comprising:

• a plurality of slots formed in an iron core, and
• a plurality of split coils inserted into the plurality of slots, wherein each split coil of the plurality of split coils are coated with an insulating film,
• wherein each split coil includes:
• a plurality of first bent portions having an inner peripheral side thicker than a radially opposite outer peripheral side of the plurality of first bent, the first bent portions having a cross-section formed in a trapezoidal shape,
• a second bent portion having an impression on an inner peripheral side of the second bent portion, and
• a straight portion, having a rectangular cross-section, disposed between the first bent portion and the second bent portion,
• wherein the second bent portion is arranged between two of the plurality of first bent portions.