Design And Analysis Of Control System For PCB Automatic Exposure Machine

Nowadays,with the rapid advancement of information technology and the emergence of various emerging technologies,electronic information products have more and more functions.As a result,the standard of PCB,the main carrier of PCB,is getting higher and higher.The key of PCB manufacturing is that imaging technology requires large area and high precision.PCB imaging relies on exposure equipment to transfer negative circuit information to conductive copper substrate.Therefore,exposure equipment is the key to ensure the quality of PCB.At present,China's PCB production ranks first in the world,and the exposure equipment market has great potential.Therefore,independent research and development of high-end PCB exposure equipment is of great significance.As the main equipment of PCB exposure production,exposure machine can be divided into manual exposure machine,semi-automatic exposure machine and automatic exposure machine according to the degree of automation.Most small and medium-sized PCB manufacturers in China still use low-end manual exposure machine,which is limited by the purchase cost of higher-grade equipment.As a result,the market competitiveness of high-end PCB products is not strong,and the demand for high-performance automatic exposure machines made in China is very urgent.Based on the production process of automatic exposure machine,combined with the mechanical structure characteristics,aiming at the practical application,peripheral auxiliary facilities are used to replace manual work to improve production efficiency,and the main part of the exposure machine is connected to achieve the goal of material handling to the whole process of exposure processing without human beings.Automatic guided vehicle(AGV)is applied to the automatic exposure machine,and the truss manipulator is used to move the materials.The independent high precision alignment system is mounted to improve the process accuracy while solving the loss of other components.The high precision linear motor is used to transfer the separated frame components into the integral exposure room for exposure processing.Therefore,the control system can be divided into main cont rol management system,handling subsystem,counterpoint subsystem and exposure subsystem.The handling subsystem is responsible for dispatching the AGV traction material transfer turnaround vehicle,controlling the truss manipulator to transfer material to the alignment platform and from the frame to the turnaround vehicle.According to the function characteristics of AGV,wireless communication technology is used to connect industrial control equipment for scheduling,decompose the action of truss manipulator,collect the effective space trajectory nodes one by one,use numerical calculation method to plan the motion trajectory,get the reference of motion control input,and then convert it into control program,drive the manipulator movement,and complete the task of moving.The alignment subsystem is used to align the through holes of the negatives circuit and the baseboard to solve the problem of inaccuracy caused by manual alignment.The position of the reference alignment holes are captured by machine vision.After processing by the image detection equipment,the position and attitude transformation data of the platform are output to the controller to drive the mechanical platform.The mathematical model of the mechanical structure of the platform is established,and the feed of the driving parts is obtained by analyzing the motion relationship between the dynamic and static platforms.The control accuracy of the platform motion is further studied,and the feasibility of the platform is verified by comparing the actual test data with the theoretical values.The function of the exposure subsystem is the most basic characteristic of the exposure machine.It is closely connected with the main control system.It controls the switch of double-frame to expose in the exposure room,and the high precision transfer of the base plate is completed by the linear motor-driven manipulator.The application of the multi-axis centralized drive card and the linear drive system is analyzed.Considering various working conditions,the layout of main control interactive management interface constitutes a complete control system design.In this paper,a new type of automatic exposure machine is proposed,which focuses on the design and analysis of its control system,optimization of material handling and transfer process,improvement of equipment production efficiency,application of high-precision automatic alignment technology in PCB exposure production,which provides guarantee for high-quality PCB.Centralized control software system ensures the normal operation of the equipment and provides research for the follow-up control system of automatic exposure machine.The system provides basis and effective reference.