Design And Implementation Of A CNC State Monitoring And Control System

With the new wave of scientific and technological revolution and the general trend of national industrial upgrading and transformation,the information and intelligent development of manufacturing will accelerate.CNC machine tools,as a very important role in manufacturing industry,is the key of modern production and processing.the using of the CNC machine determines the advanced level of manufacturing.Although China has been widely used in the production of CNC machine tools,but compared with the manufacturing sector in developed countries,most of our manufacturing enterprises on the application of CNC machine tools is still not enough.At present,the manufacturing workshop on the use of CNC machine tools exist a low degree of management,the production process is opaque,there are “information islands” and other issues.Manufacturing industry is an urgent need to explore how to establish a CNC equipment monitoring and management system to improve the efficiency of equipment management.In view of the present situation and development trend of domestic machine tool application,this paper takes Siemens SINUMERIK 840 D sl numerical control system as the research object,and discusses the numerical control machine status monitoring technology of PLC communication using third party communication class library.Firstly,this paper analyzes the hardware and software characteristics of Siemens 840 D sl CNC system,including hardware architecture,hardware connection communication mode and numerical control system data definition type and function,840 D sl CNC system secondary development function support,for the establishment of 840 D sl NC system data acquisition communication program to prepare.Secondly,based on the analysis of the shortcomings of 840 Dsl existing secondary development function on data acquisition and communication function and the PLC programs and growing of PC and PLC technology,this paper puts forward data state acquisition and control for CNC machine based on PLC data communication.And through the analysis of PLC communication protocol and monitoring system development features,this paper explores the use of appropriate third-party communication components as the underlying infrastructure communications.Finally,based on the analysis of the feasibility of selecting the Snap7 third-party communication class library to realize the PLC data communication of the 840 D sl numerical control system,based on the analysis of the data acquisition and state control requirements of the NC machine tool in production practice,this paper designs distributed DNC machine status monitoring system based on PLC communication.According to the characteristics of design requirements,the system architecture,database architecture and application function realization are planned.By using 840 D sl CNC machine tool bench to test the designed system,the technical feasibility of the method presented in this paper is verified.