| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a high frequency hardening device capable of forming an uniform hardened layer on an inner peripheral face even in the case of a cylindrical work, in which a recessed grove is formed on an outer peripheral face around an axial center. SOLUTION: The device is provided with an inside cooling jacket 200, which injects a cooling liquid L to an inner peripheral face W1 heated by a high frequency heating coil 100 inserted to an inside of a cup part W, an outside cooling jacket 300, which injects a cooling liquid L to an outer peripheral face W2 of the cup part W and a moving mechanism, which moves the high frequency heating coil, the inside cooling jacket and the outside cooling jacket along an axial center WL, the outside cooling jacket injects the cooling liquid L to a recessed groove W3 until the heating of the inner peripheral face W1 corresponding to the part where the recessed groove W3 is formed, is competed. When the heating of the inner peripheral face corresponding to the part where the recessed grove W3 is formed, is completed, the outside cooling jacket and the high frequency heating coil are synchronously moved, the cooling jacket injects the cooling liquid L less than the quantity to the recessed groove W3.</p> |
