The Development Of Electrical Control System Of Screen Printing Machine Based On PLC Control

Screen printing, for no limit of printing stock's size and shape, having strong adaptability ofink and broad adjusting range of ink thickness, is widely used. So it's necessary to develop thescreen printing machine with high precision, good performance and easy operation.The thesis combines with the productive circumstance of the old screen printing machines,makes use of the mature programmable control technique and terminal control technique, andchanges and redesigns the electrical control system of the old screen printing machine.This thesis designs the hardware in detail on the base of task analysis of BWSP-9011HAnew screen printing machine's electrical control system. It includes the configuration of maincontrol PLC, functional module, HMI and so on, as well as schematic circuit diagram'sdetailed design. Speed regulation control adopts the variable frequency adjusting technology,PLC controls inverters by adopting extended memory communication. Positioning controluses servo driving system, adopts half closed loop control, gets help from proximity switchand makes use of PLC and positioning module as controllers controlling the servo motor, anddrives the slipway to achieve glass's transport accurately.Then the thesis designs the structure of the control system's PLC program on the base ofthe modular programmable thought, and compiles the initialization, manual, automatic,numerical computation, data communication, surveillance procedures and so on. Besides, theprogram of programmable terminal is developed by using EasyBuilder, designs humanmachine interface, and implements the interaction between the user and the system.After lab and spot's debugging and commissioning, BWSP-9011HA screen printingmachine studied in this thesis not only has favorable reliability and high work efficiency, butalso shows good performance and friendly human machine interface, finally implements the automation during the printing process. The operation verifies, the measures adopted in thethesis have an ideal effect in the system's operating process, and achieves scheduled target.