T4240B镗床传统电气控制系统改造问题研究-毕业设计正文.doc

摘 要 本论文是研究机械加工中常用的T4240B镗床传统电气控制系统的改造问题，旨在解决传统继电器——接触器电气控制系统存在的线路复杂、可靠性稳定性差、故障诊断和排除困难等难题。由于PLC电气控制系统与继电器——接触器电气控制系统相比，具有结构简单，编程方便，调试周期短，可靠性高，抗干扰能力强，故障率低，对工作环境要求低等一系列优点。因此，本论文对T4240B镗床电气控制系统的改造，将把PLC控制技术应用到改造方案中去，从而大大提高镗床的工作性能。论文分析了T4240B镗床的控制原理，制定了可编程控制器改造T4240B镗床电气控制系统的设计方案，完成了电气控制系统硬件和软件的设计，其中包括PLC机型的选择、I/O端口的分配、I/O硬件接线图的绘制、PLC梯形图程序的设计。对PLC控制镗床的工作过程做了详细阐述，论述了采用PLC取代传统继电器——接触器电气控制系统从而提高机床工作性能的方法，给出了相应的控制原理图。 关键词：可编程控制器；梯形图；电气控制系统 Abstract This thesis is to study mechanical processing in commonly used T4240B boring traditional electrical control system, aiming at solving the problem of traditional relay contactor electric control system of the existing line complex, poor stability and reliability, fault diagnosis and exclude the difficulty. As a result of the PLC control system and electrical relay, contactor electrical control system is compared with simple structure, easy programming, debugging, short cycle, high reliability, strong anti-interference ability, low failure rate, the work environment low requirement of a series of advantages. Therefore, the transformation of T4240B electrical control system for boring machine, will PLC control technology is applied to the transformation of the program, so as to greatly improve the working performance of the machine. The paper analyzed the control principle of T4240B boring machine of the, making the programming controller reforming T4240B boring machine electrical control system design, completed the design of electrical control system of hardware and software, including the distribution of the PLC type choice, the I / O port, I / O wiring diagram of the hardware drawing, PLC ladder diagram program design. PLC control of the working process of boring machine made in detail, discusses the use of PLC to replace traditional relay - contactor electrical control system so as to enhance the performance of the machine, gives the corresponding control principle diagram. Keywords：Programmable controllerLadder diagra