| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a device for induction-hardening a rack, which prevents the rack from being distorted after hardening, without using a complicated cooling means, and to provide a method for inhibiting distortion of the rack during hardening. <P>SOLUTION: The high-frequency induction-heating hardening device comprises a line coil 10 for induction-heating the peripheral surface of a gear tooth part w1 of the rack W, a cooling jacket for jetting a liquid coolant to the induction-heated gear tooth part w1 of the rack W, and a rotating mechanism 20 for rotating the rack W, and energizes the line coil 10 for a predetermined time, when the gear tooth part w1 of the rack W faces an upper conductor 12 of the line coil 10 at an initial position. The device further comprises a control part 30 for induction-heating a gear tooth W1a in the gear tooth part w1 of the rack W to the hardening temperature in the above state, and then induction-heating the peripheral surface of the gear tooth part w1 in the rack W by making the rotation mechanism 20 continuously operate. In the control part 30, a ratio of a stopping period to an operating period of the rotation mechanism 20 in the all heating period T is previously set so that the distortion can not occur in the rack W after hardening. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
