| 摘要 |
<p>PURPOSE:To improve the fatigue strength of a gear without deteriorating the surface roughness of the gear by realizing induction heating with the specific frequency as a heating means at the time of quenching by reheating tooth bottom part of the gear harden-treating the surface. CONSTITUTION:The gear 4 after the surface is harden-treated, is fitted to a gear fixed shaft 5, and while rotating the fixed shaft 3 in the R direction in the condition of approaching to a coil 1 for induction heating, the current having <=10KHz frequency is conducted through the coil 1 and the tooth bottom part of the gear 4 applying only the surface hardening treatment by the induced current. After heating the prescribed temp., the gear rotating axis 3 is shifted to the S1 direction and the gear 4 is quickly cooled with the water cooling Jacket 2 to reheat and quench the gear. To the round part of the tooth base, the compressive residual stress is given and the fatigue strength is remarkably improved at more than the gear applying only the surface hardening treatment. Further, as a shot peening treatment is not applied, the surface roughness of the gear is not deteriorated.</p> |
