Electrical Control And Application For A CNC Double Column Vertical Heavy Turning & Milling Machine

The characteristics of vertical turn-milling composite machine tool produced by Wuhan Heavy Duty Machine Tool Group Corporation are high precision,large cutting torque,strong bearing capacity of worktable and large processing specifications.Th e author studies some control technologies of vertical turn-milling composite machine tool.In view of the characteristic of processing face milling in turning center,this paper designs a polar coordinate interpolation processing technology and conducts simulation in MATLAB software.The simulation re sults show that this technology can meet the machining accuracy of machine tool.The use of the polar coordinate interpolation technique can switch the two axis linkage of X axis and Y axis in XY plane into the linkage of X axis and C rotation axis and sol ve the problem that vertical turn-milling composite machine tool without the actual Y axis,achieving the processing purpose.According to the characteristic of strong bearing capacity of the worktable required by heavy duty vertical lathe,this paper stud ies the hydrostatic pressure bearing technology,calculates the flow of oil supply system of hydrostatic guide way worktable and determines the relationship between the oil film thickness of guide way and temperature,load and flow.In order to make the oi l film thickness be in a good state,it designs a close-loop control system and compiles PID control algorithm blockette based on PLC.For the deficiencies of fixed regulator parameters and certain lag of PID regulator,the paper puts forward the technical scheme of fuzzy adaptive control algorithm,conducts simulation in MATLAB software,verifies the feasibility of the method,builds an experimental platform of hydrostatic guide way rotating table and compares the differences between the experimental data and theoretical data.The experimental data shows that the theoretical formula can be accurately applied to engineering practice.This paper calculates the velocity resolution of analog spind le encoder in 840 D SL NC system,and compares the performance difference of the use of TTL encoder and 1VPP encoder and determines the selection scheme.And this paper explains the return-to-zero principle of the distance-coded grating ruler and circular grating,applies them to SIEMENS NC system,which reduces the retu rn-to-zero time of machine tool.The crossrail of vertical lathe shall make lifting movements on the column guide way in order to meet various processing heights.This paper conducts the calculation and selection for the crossrail motor and soft starter,designs a crossrail synchronous protection device to prevent the crossrail tilting and describes crossrail moving control process in detail to ensure the safe and reliable operation.Through the above research,the electrical system of vertical turning-milling composite machine tool has perfect function s and the system is safe and reliable.