| Roll bending technology based on the principle of three points circle,using the relative position change and rotation of the work roll and having a continuous elastic-plastic bending to obtain a predetermined shape and accuracy of the workpiece,has been widely used in aviation aerospace,military weapons,automobile industry,vehicle industry and other industries.However,the main feeding of the plate rolling occasions is carried out by manual feeding method,which has the problems of poor quality,low production efficiency and safety accidents.The automatic feeding technology of the bending machine is a kind of technology for the feeding of the plate rolling,which has the advantages of high efficiency and high security,etc.Its application helps to improve the automation level and quality of the plate rolling for the bending machine.Therefore,combining with the requirements of the feeding action of the bending machine,this paper designs and develops a device of automatic feeding system that can be applied to the roll bending machine,and the main research work is as follows:(1)The feeding process of the rolling bending machine is analyzed,and the overall program of automatic feeding system is designed to realize the handing and pushing functions of the plate.The structure and the driving system for the handling device(including the vacuum sucker device)and the pushing device are designed respectively.(2)A parametric model of the handling device is established.Based on the finite element theory,the static and modal analysis of the handling device under pickup plate position is carried out by using ABAQUS software.The result of static analysis shows that the structural strength and stiffness of the designed handling device meet the requirements.The modal analysis obtains the first 6 natural frequencies of the handling device.When the handling device is in a low speed operation,the external excitation frequency should be shifted to improve the stability of the device.(3)According to the working process of the automatic feeding system,the hardware part of the numerical control system is set up.The control system adopts the typical “HMI+PLC” structure,analyzing and studying the communication mode between different hardware.The software part mainly analyzes the control methods of the servo motor and the speed measurement using the encoder.(4)In view of the stability of the plate handling,the speed fuzzy PI control of the start-up servo motor is studied.The use of MATLAB/Simulink software is simulating servo motors,and fuzzy PI and traditional PI controls are compared,which shows that the speed response of the former,with higher regulation precision and smaller speed overshoot,is quicker than the later and the settling time of the former is greatly decreased comparing the traditional PI control.Then,the use of the fuzzy PI control can certainly weak the chattering phenomenon of handling sheet in the process. |
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