| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a control method of hardening depth, with which the defective work is reduced, and also the hardening depth control with high precision is attained even in the case of changing a hardening apparatus. SOLUTION: When plural works of the same kind are surface-hardened with a high frequency induction heating for the purpose of reserching the relation between the hardening depth and a coil voltage, the heating and hardening are executed with the preset coil voltage, and the allowable range of a pattern of the necessary coil voltage to control the hardening depth in the standard range is found from the relation between the pattern changing with time of the coil voltage and the hardening depth obtd. The changing pattern of the coil voltage in each heating in the practical hardening after this research hardening, is analyzed and the hardening depth is adjusted by judging whether the changing pattern of the coil voltage is controlled with the allowable range or not.</p> |
