Study On Milling Technology Of Five-Axis EDM Machine Tool

Electrical Discharge Milling is a new kind of processing technology since 1990s. Electrical Discharge Milling has not only the characteristics of Electrical Discharge Machining which can not be restricted by physical properties of workpiece materials, such as strength, hardness, toughness, but the features of milling workpieces using multi axes synchronously. Therefore, Electrical Discharge Milling has wide prospect of application in aeronautical and astronautical manufacturing industry, mold machining industry and so on.Based on the theoretical analysis and process experiments, the thesis investigates the key technical problems incorporating the research and development of five-axis linkage EDM machining tool. The main research contents are as follows:(1) The structural layout scheme of five-axis EDM machine tool has been designated by analyzing movement function. The structures of the swing mechanism and the electrode holders are designed. Several designs are proposed and compared each other. Finally, the optimal scheme is selected as the final decision-making scheme.(2) The compensating model with electrode wear is established on the basis of cylindrical electrode loss rule. The contrasting experiments of size precision are carried out between no-compensating and compensating EDM Milling. The experimental results indicate that the compensating model can reflect the electrode loss status accurately during processing and the compensating method of electrode wear proposed is feasible.(3) Accounting for the particular properties of discharge machining, NC programming technology in EDM Milling is studied. On the basis of the compensating model presented, the thesis puts forward the path generating algorithm of the electrode movement on typical two-dimensional profile,plane pockets and surface machining. The solution of inverse kinematics of five-axis EDM machining tool is achieved based on the coordinates system of machine tool. The mathematical expression of driving value of each axis is deduced out, which provides an important theoretical foundation for developing automatic programming software for CNC system of EDM machining tool.(4) The machining process route and the selecting principles of processing parameters in EDM Milling are summarized. Through the machining experiments, the influencing factors of machining accuracy and efficiency are analyzed, and the correctness of the algorithm on electrode movement path proposed and the feasibility of UG CAM application in EDM Milling are verified.