Research Of Control System For Paper And Yarn Compounding Bag Bottom-Pasting Machine Based On PLC

With the continuous development of society and people's awareness of environmental protection gradually increased,the paper packaging which easy to degrade replaces the plastic packaging has become an inevitable trend in the development of the packaging industry.The new paper and yarn compounding bag has the advantages of high strength,good toughness,save material and so on,and can be applied to the packaging of cement,lime and chemical raw materials.At present,this new environmentally friendly bags have become the mainstream of paper packaging products.However,the paper and yarn compounding bag bottom-pasting machine has many processes,so the domestic bottom-pasting machine for the paper and yarn compounding bag are still many deficiencies.Although the foreign bottom-pasting equipments are high efficiency and high degree of automation,but the higher prices,late maintenance inconvenience,production costs are too high,is not conducive to business.Therefore,according the actual needs of China,design a paper and yarn compounding bag bottom-pasting equipment has important practical significance.Aiming at the demand of Chinese enterprises,based on the process of paper and yarn compounding bag bottom-pasting,a control system of paper and yarn compounding bag bottom-pasting machine based on PLC is designed.The main contents are divided into three parts: design of control system,deviation control system design,monitoring system design.First of all,according to the process,technical parameters and control requirements of the paper and yarn compounding bag bottom-pasting,after comparing the control methods of several modern industrial equipments,it is determined that the S7-200 PLC is the core of the control system of the bottom-pasting machine,stepper motor as the power source of each station to drive mechanism action,combined with temperature sensor,photoelectric sensor and other detection components and touch screen man-machine interface,designed the control system of strong circuit diagram,PLC input and output circuit,PLC input and output Terminal configuration and software design of each subsystem and so on.Secondly,the paper bag in the process of bottom-pasting,inevitably encounter the problem of deviation,impact the subsequent processing.Correction control system is designed for paper bag deviation problem,bridge balance principle is used to detect the optical signal and after A/D module convert it into the electrical signal that PLC can be identified,tend the paper bag in the correct position when the electrical signal comparison.Determining whether the paper bag deviation and do corresponding operation.This is divided into a detection part and a control part,and includes a deviation detection device,a measurement circuit,a stepping motor driver,a signal acquisition program.Finally,the MP277-type touch screen introduced by Siemens is based as a man-machine interface,so that operators can monitor the production line through the man-machine interface status.The main interface of the user login screen,parameter setting screen,running status screen and fault display screen is designed.The configuration page of the man interface is completed by using the WinCC flexible configuration software configure screen.In this thesis,a control system based on PLC is designed for the existing problems,and the PLC is used as the control core,and the devices such as temperature sensor and photoelectric sensor are used to realize the remote control of the production line through the touch screen.The bottom-pasting equipment can operate automatically according the size user needs and the bottom-pasting efficiency and automation have improved.