Abstract: A method of manufacturing coils that includes forming a predetermined number of U-shaped conductor segments. The U-shaped conductor segments are twisted using first twisting formation jig composed of a first inside ring and a first outside ring and a second twisting formation jig composed of a second inside ring and a second outside ring. The U-shaped conductor segments that are twist formed in radially inward directions are radially compressed. The U-shaped conductor segments are twist formed by holding one of each pair of straight portions by holding slots that are circumferentially formed in each of a first and second inside rings and first and second outside rings. Next, first and second inside rings and the first and second outside rings are coaxially rotated.

Abstract: A method of manufacturing coils that includes forming a predetermined number of U-shaped conductor segments. The U-shaped conductor segments are twisted using first twisting formation jig composed of a first inside ring and a first outside ring and a second twisting formation jig composed of a second inside ring and a second outside ring. The U-shaped conductor segments that are twist formed in radially inward directions are radially compressed. The U-shaped conductor segments are twist formed by holding one of each pair of straight portions by holding slots that are circumferentially formed in each of a first and second inside rings and first and second outside rings. Next, first and second inside rings and the first and second outside rings are coaxially rotated.

Abstract: A coil forming apparatus includes a twisting formation unit that twist-forms a predetermined number of U-shaped conductor segments. The twisting formation unit includes a first twisting formation jig composed of a first inside ring and a first outside ring and a second twisting formation jig composed of a second inside ring and a second outside ring. Each of the first and second inside rings has the same number of circumferentially disposed holding slots as the stator slots to hold one of each pair of straight portions. Each of the first and second outside rings has the same number of circumferentially disposed holding slots as the stator slots to hold the other of each pair of straight portions of the U-shaped conductor segments. The first and second inside rings and the first and second outside rings are coaxially coupled to shift relative circumferential position between the inside rings and the outside rings by a predetermined angle to twist the turn portions of the U-shaped conductor segments.

Abstract: A coil forming apparatus includes a twisting formation unit that twist-forms a predetermined number of U-shaped conductor segments. The twisting formation unit includes a first twisting formation jig composed of a first inside ring and a first outside ring and a second twisting formation jig composed of a second inside ring and a second outside ring. Each of the first and second inside rings has the same number of circumferentially disposed holding slots as the stator slots to hold one of each pair of straight portions. Each of the first and second outside rings has the same number of circumferentially disposed holding slots as the stator slots to hold the other of each pair of straight portions of the U-shaped conductor segments. The first and second inside rings and the first and second outside rings are coaxially coupled to shift relative circumferential position between the inside rings and the outside rings by a predetermined angle to twist the turn portions of the U-shaped conductor segments.

Abstract: In a twisting formation method having an inside jig provided in a ring shape with inside holding portions for folding one of the straight portions of a near letter U shaped wire and an outside jig provided in a shape of ring concentric with that of the inside holding portions with outside holding portions for folding the other of the straight portions, the connecting portion of the near letter U shaped wire being formed in a twisted shape by rotating relatively the inside and outside jigs, the method includes urging leading ends of the straight portions and the connecting portion in a contracting direction.