| 摘要 |
PURPOSE:To harden each tooth surface and keep the depth of hardening from the addendum at a proper value, by interlocking the indexing-sending mechanism to intermittently send the baking heads for high frequency heating of each tooth surface of a rack to each indexing position, with the hardening-sending mechanism to send and retreat the baking heads into and out of the heating positions. CONSTITUTION:Each tooth of a rack 24 amounted on a support jig 22 is hardened at high frequency by means of a hardening coil 26 in a hardening head 30 in the following procedure. That is, a motor 20 rotated and driven in normal or reverse direction is coupled with a first drive shaft 86 of an indexing-sending mechanism, and a pair of gears 87, 88 fitted to this shaft 86 causes the shaft 86 and a cam shaft 106 of a hardening-sending mechanism to rotate in cooperation under a specified rate determined by a gear ratio. When the shaft 86 is driven and rotated in normal reverse direction by the motor 20, the rotating torque is transmitted to a second drive shaft 90 through intermittent sending mechanism 89 and reduction gear 90, and, as a result, a feed screw 84 is put into rotation. According to this rotation, the hardening head part 30 receives a feeding action in the longitudinal axial line of the rack 24. |
