摘  要

现代数控机床是未来工厂自动化的基础。数控设计范围大、潜力大、投资少、见效快，促进制造业技术进步的重要手段。因此，数控系统设计车床的研究具有重要意义。
本文在叙述了数控技术的历史、现状和发展的基础上，通过机床设计的总体思想，提出了数控化设计的技术方案和新数控系统的选型配置方案;提高了传动的精度，重新设计机床的控制逻辑，通过对伺服系统的分析，完成了机床各主要参数的优化和匹配。
数控车床不仅能够车外圆还能用于镗孔、车端面、钻孔与铰孔。与其他种类的机床相比，车床在生产中使用最广。
本论文首先介绍了我国数控机床发展的过程与现状 ,并分析了其存在的问题 ;对数控机床的发展趋势进行了探讨；并对Φ430mm数控车床传动系统进行了设计与计算。
主轴箱有安装在精密轴承中的空心主轴和一系列变速齿轮组成。数控车床主轴可以获得在调速范围内的任意速度，以满足加工切削要求。
目前，数控车床的发展趋势是通过电气与机械装置进行无级变速。变频电机通过带传动和变速齿轮为主轴提供动力。通常变频电机调速范围3—5，难以满足主轴变速要求；串联变速齿轮则扩大了齿轮的变速范围 。
本设计将原来的带轮不卸荷结构变为了带轮卸荷结构，使输入轴在带处只受转矩，将轴上的径向力传动到车床机体上,改善了输入轴的受力情况。
关键词：Φ430mm，数控车床，机床，设计，数控系统。 
 

Abstract

Modern CNC machine tools is the basis for the future of factory automation. CNC design range, potential is great, less investment, quick effect, promote manufacturing industry technological progress is an important means of. Therefore, the design of NC system for lathe has important significance to the research of.
This paper describes the CNC technology history, current situation and development on the basis of machine tool design, through the overall idea, put forward the technical scheme design of NC and CNC system selection scheme; the drive to improve the accuracy, to design machine tool control logic, through the servo system of a machine tool, completed the main parameters optimization and matching.
NC lathe can do boring, facing, drilling and Reaming in addition to turning.The use of lathes in the production than the other types of machine tools and more. And compared to other types of machine tools, lathes in the production is the most widely used.
In this design ,the development and current situation of NC machine in China was introduced and a series of problems were presented .The development trend to NC lathe was discussed.Some countermeasures was presented for the development of NC machine in China and then the headstock ofΦ 430 lathe has been calculatly designed . Headstocks is composed of the hollow spindle which is installed in precision bearings and a series of transmission gears. The spindle can obtain any speed in the speed range to meet the processing requirements of cutting.
At present, the development trend is to provide a continuously variable speed through the electrical or mechanical devices . Variable Frequency Motor conveys the power through belt drive and a set of transmission gears. The speed range of Variable Frequency Motor is usually 3-5 , which is difficult to meet the speed range requirements of the spindle speed; The transmission gears is to expand the scope of a variable-speed to meet the speed range of the spindle .
In addition, in this design the design of the belt drive has been changed from the original unloading structure into the loading structure, transmissed the force to the lathe body so that input shaft is only forced torque, improved the forcing state of the input shaft.  
Key words:Φ 430mm, CNC lathes, machine tools, design, numerical control system.