Research On Control System Of Discontinuous Electrophoresis Production Line Of Automobile Frame

Cathode electro-coating is an important metal products surface coating forming method, the process is environmentally friendly and safe and the coating has a good quality. This topic comes from an automobile frame electrophoresis coating production line of an electrophoresis coating enterprise, its process uses cathodic electrophoretic coating technology. At present, the control of the production line transportation system is manual. And only one crane is transporting automobile frames in the line, so its productive efficiency is very low, and the product quality cannot be guaranteed.To transform the chassis frame electrophoresis production line in the enterprise into an discontinuous type, semi-automatic one, is the main purpose of this research. Meanwhile, in order to further improve the work efficiency, two cranes will be used in transporting automobile frames in the line. At last, chooses PLC of Siemens S7-200 series, and research a set of automatic control system used in the electrophoresis production line. In the research of this paper, the work program of electrophoresis production line was firstly determined; And then, according to the work program to complete the hardware design and software design of the control system; Simulation experiment was carried out at lasto Experimental result shows that, the hardware of the control system met the requirement of precision and convenient installation, etc, and the software run well. So, the simulation experiment achieved the expected effect.About the research of control system in this paper, the main achievements as below: analysed the two work program, chose the work program I below paper as the last work program, it is high-efficiency, easy-operating; Furthermore, in order to verify the rationality of work program I, some flash animations about work programs had been made; Chose two PLC of CPU226 used in the control of two cranes respectively, the control system is simple and stable; After further analysis and comparison of various object position detection method, chose the indirect detection method to detect the hook height position using an absolute rotary encoder, the method is simple to use, easy to install, stable in performance, and high precision; An anti-collision device was designed to prevent collisions between two automobile frames in the running line, Learned the programming principle and idea of Siemens S7-200 series PLC programming software STEP7-Micro/WIN, finished the design of control system software; Built a simulation experimental platform, finished the simulation experimental verification.The research work in this paper reached the expected goal, in theory, the production line control system can complete the electrophoretic painting work according to the requirements in practical application.