| 摘要 |
PURPOSE:To prevent the variation of control lag due to the rotational irregularity of a hob by a method wherein the rotation of a work is controlled by a signal, which is obtained by levelling off the the outputs of a pulse encoder to detect the amount of rotation at predetermined intervals of time. CONSTITUTION:In case that a gear is cut by hobbing, the rotational irregularity is caused in the hob by means of the cutting force applied to the hob, resulting in exerting an adverse influence upon the synchronous rotation control of the work. An output pulse train of the encoder 7 denoting the revolution speed of the hob 1 is levelled off at predetermined intervals of time such as one revolution of the hob by means of a levelling-off circuit 14 of pulse inputs and the pulse train corresponding to sadi average value is outputted to a pulse distributing circuit 8a in order to synchronously rotate the work 13 mounted on a rotary table. In such a manner as described above, the change of the amount of lag of synchronous rotation control of the work due to the rotational irregularity of the hob is prevented, resulting in enabling to realize a highly accurate gear hobbing. |
