| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an induction hardening method by which strength of a gear is improved by hardening the tooth bottom over the wide range without hardening one end part in a tooth trace direction of an addendum. SOLUTION: The gear 10 is fixed to a jig 40 and annular induction-heating coil 50 is approached to the addendum 22. In this state, high frequency current is supplied into the induction-heating coil 50 and the other portion 22b of the addendum 22 and the tooth bottom 24 are heated so as to become a prescribed temperature. Successively, the other portion 22b of the addendum 22 and the tooth bottom 24 are allowed to cool by about 2 sec. Just thereafter, the other portion 22b of the addendum 22 and the tooth bottom 24 are heated to a prescribed hardening temperature. After this heating, these are rapidly cooled by injecting cooling liquid to these portions.</p> |
