CNC机床伺服驱动系统的自动升降速处理

On the problem of automatic speed control in CNC machine tool servo drive systems

CNC机床在启动、停止或切削加工过程中改变进给速度时 ,由于伺服驱动元件的响应频率跟不上微机插补运算所输出的进给指令信号频率 ,而容易产生失步或超程 ,直接影响加工精度。本文较为详细地分析了以步进电机或交直流伺服电机作为伺服驱动元件的开环、闭环 (半闭环 )控制系统中产生以上问题的原因 ,介绍了为解决以上矛盾所采取自动升降速处理的原理、方法和步骤。

When changes of feed rate are found to be necessary in a CNC machine tool system at the points of its staring , stopping or in process of its working , stepping out and / or overstepping range are very likely to take place because of the failure of the response frequencies of servo drive parts in keeping pace with those of instruction signals output by the micro-computer interpolations. This phenomenon no doubt will exert direct influences on the machining accuracy. In this paper , a detailed analysis has been carried out on the reasons to produce above mentioned troubles in the open-loop or closed-loop (inclusive of semi-closed-loop) control systems equipped with step motors or DC servo motors as their servo drive elements. Moreover ,are also introduced the principles ,methods and steps adopted by the automatic speed control technique to solve these problems.