Dynamic Analysis And Simulation Of Feeding System Of Precision Machine Of Boring And Milling

NC machine tool is the fundamental equipment of the modern manufacturing. With the development of manufacturing technology towards to high speed and high precision, NC machine tool is demanded for having higher requirements of machining accuracy and faster movements of precision so as to reduce processing program and improve the efficiency of the machining. Therefore, the high requirements about NC machine are put forward in the speed, accuracy, stiffness etc. The numerical control feeding system is one of the important links of the numerical control machine processing, so the performance of the feeding system greatly influences the precision of the machine. Now, studying feeding system is one of the important topics in numerical control machine.This dissertation selects the feeding system of the gantry boring and milling machine as the research object in accordance with the concept of the modular design. From the point of view of modular structure, feeding system is classified into the drive motor module, mechanical transmission device module and supporting module of table guide system and so on. Then, the characteristics of the module are also detailed introduced. The nonlinear friction, nonlinear clearance and other influential factors of the feeding system which exist in mechanical transmission of NC machine tool were in-depth studied. Also the mathematical models of the factors were established.The milling force generated in machining influences work table in many ways. In this dissertation, the model of table system under the condition of milling forces is established by using Lagrange method. Moreover, micro dynamic differential equations of table are also established. Then the equation is transferred into the state space model and the position deflection of the table solved through the establishment of the Simulink block diagram. The comprehensive mathematical model including nonlinear friction, nonlinear clearance of feeding system of work table is put forward. In consideration of the traditional PID control parameters is not easy to achieve, coordinating parameters is adopted about the tri-cyclic structure of the servo control system by using ITAE performance index combining numerical optimization function of Simulink. It has certain practical significance.