Cold pressure welding apparatus, coil manufacturing apparatus, coil, and method of manufacturing the same
The cold pressure welding apparatus includes a first holding part capable of sandwiching a first flat conductor, a second holding part disposed opposite to the first holding part and capable of sandwiching a second flat conductor, and a drive part for moving the first holding part and the second holding part. The drive part can move the first holding part and the second holding part between a first direction separated position and a close position along a first direction. The drive part can move the first holding part and the second holding part between a second direction separated position and a sandwiching position along a second direction.
1. A method of manufacturing a coil comprising a helical structure and having a predetermined length along a helical loop of the helical structure, the method comprising:
providing a plurality of flat conductors, wherein each of the flat conductors has a first end and a second end that are flat and are terminal portions of a flat conductor with respect to a direction of the helical loop, and when the plurality of flat conductors is arranged to form a structure having the helical structure by connecting flat conductors at the first and second ends thereof, the structure has a length along the helical loop of the helical structure that is longer than the predetermined length of the coil along the helical loop;
pressing the first end of one of the plurality of flat conductors against the second end of another of the plurality of flat conductors in the direction of the helical loop so that the two flat conductor are cold-welded and a total length of the two welded flat conductors along the helical loop is shortened by the pressing; and
repeating the pressing for all of the plurality of flat conductors so that a total length of the plurality of welded flat conductors along the helical loop becomes equal to the predetermined length of the coil along the helical loop.
2. The method of claim 1 , wherein a plurality of welded portions are formed along the helical loop of the coil.
3. The method of claim 1 , wherein at least one of the plurality of flat conductors has a U-shape with two corners.
4. The method of claim 1 , wherein all of the plurality of flat conductors have a U-shape with two corners.
5. The method of claim 1 , wherein the coil and the structure have different structures when viewed in a longitudinal direction of the coil and the structure.
6. The method of claim 1 , wherein the two flat conductors, except for welded portions, are elastically deformed or plastically deformed along the helical loop during cold welding.
7. The method of claim 6 , wherein an amount of elastic deformation or plastic deformation is set so that interference between the two flat conductors to be welded and holding parts holding the two flat conductors during the cold welding is avoided.