| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a coil for induction hardening and an induction hardening method capable of hardening an inner surface of a small hole where it is difficult to harden in a conventional method, without any problem.SOLUTION: A pipe conductor in which coolant flows is used as a coil wire, and the pipe conductor is bent into an U-shape for forming a first coil part, and a second coil part whose bend direction is same to that of the first coil part and disposed in parallel to the first coil part, is formed, and a reverse U-shaped bent part extending from a termination of the first coil part to a start end of the second coil part, is also formed. In the first coil part and the second coil part, current flows in a same direction.</p> |
