| 摘要 |
PURPOSE:To make it possible to synchronize and drive a plurality of spindle drive motors by controlling the motors in a closed-loop condition by use of a PLL control means in accordance with speed instruction pulse signals which is obtained by multiplying a common reference pulse signal with a multiplying factor in proportion to shaft rotating speeds. CONSTITUTION:A reference pulse generator 12 delivers reference pulse signals in accordance with an instruction from a control section 13, and then the reference pulse signals are successively multiplied by multiplying factors proportional to spindle rotational speeds by means of successively multiplying circuits 9, 10. Further, speed instruction pulse signals are inputted to a PLL control means 7, 8 by way of a switch 11, and drive motors 1, 2 for the spindles are subjected to feed-back control through the intermediary of drive circuits 5, 6 and encoders 3, 4. Further, feed-back is made to the control section 13 through the intermediary of counters 15, 16 and an 1/F 17. Further, the PLL circuits 7, 8 are provided therein with circuits 7a, 8a for extracting a desired number of pulses from the speed instruction pulses signals in accordance with a feed length of a cutter gear under an instruction form the control section 13 during machining a gear to be machined. Thus, the spindles are driven being synchronized with each other with an arbitrary speed ratio. |
