| 摘要 |
PURPOSE:To perform no pressurizing by a collison member excepting a dedendum, and to prevent the surface of an addendum from becoming uneven, by impacting an impact member only on a dedendum and increasing this strength with the dedendum being pressurized. CONSTITUTION:A table 12 is positioned in advance to the column 14 as for a moving means to which a hob shaft 15 is fitted, so that an impact member is collided with the dedendum of a gear 21 by a table moving mechanism. When a hobbing machine 40 is then actuated similar to the case of performing grinding of the gear 21, a main body 22 is rotated according to the rotation of the hob shaft 15, an arm 24 and impact member 23 are rotated around the hob shaft 15 simultaneously with this. Then, the impact member 23 is collided with the dedendum with its intrusion to the tooth groove of the gear 21 by this rotation. At this time the impact member 23 applies the impact force corresponding to the tare on the dedendum, which is pressurized, and a residual compression stress becomes being imparted to this internal part. After the collison thereof, then, the arm is turned in the reverse direction according to the rotation of the hob shaft 15, and the impact member is released from the gear groove. |
