The Design Research On Structure Of WEDM Special Machine Tool For Precision Cycloid Gear

Cycloid gear is one of the key parts of the RV reducer,the core component of the robot,and its accuracy directly affects the transmission accuracy of RV reducer.Although there are many methods of processing cycloid gear in our country,such as gear shaping,hobbing,milling and grinding,because of the problem of equipment,they are not enough to meet the precision requirements of the cycloid gear,that is to say,the cycloid gear still need to be imported from abroad.The WEDM-LS technology can produce high precision parts,however,its core components subject to foreign technology and domestic use of two clamping way to machining cycloid tooth profile,will cause the machining error.Therefore,in order to improve the accuracy requirements of cycloid gear,it is of great practical significance to research the WEDM-LS relevant technology.Based on the forming methods of tooth profile of cycloid gear,this paper summarizes the machining methods of cycloid gear profile,and analyzes the processing principles as well as the advantages and disadvantages of each method.Considering the problem of accuracy and machining efficiency,a method of machining cycloid gear with the WEDM special machine tool is put forward,and the main parts of the structure of the special machine tool are designed and researched.The main contents of this thesis include:(1)Firstly,the overall design of the WEDM special machine tool.Secondly,use the design principle of one clamping and composite machining to design the special machine tool’s worktable which the composite device for processing cycloid gear profile and bearing hole,and the processing scheme of cycloid gear is put forward.In order to improve the performance of the composite device,the ANSYS Workbench finite element analysis software is used for the statics analysis,modal analysis and structural topology optimization of the composite device’s Z axis runner parts,and then verify compositedevice’s rationality by using ADAMS software.(2)Research on constant tension and radius compensation of electrode wire in wire feeding system of the WEDM special machine tool.In order to determine the effect of the tension of the electrode wire on its natural frequency,the vibration of the electrode wire is studied theoretically,and then the simulation is carried out based on the ABAQUS analysis software.Finally,the electrode wire’s constant tension control scheme and radius compensation scheme are put forward,and verify its feasibility by using the MATLAB Simulink.(3)Select the electrical parameters of machining cycloid gear and CAXA WEDM simulation.Firstly,the influence of electrical parameters on the machining efficiency and surface roughness is analyzed by experiments,and the best combination of electrical parameters is discussed by the orthogonal experimental design.Then the CAXA WEDM software is used to generate and simulate the machining cycloid tooth profile trajectory and generate the machining 3B code.Based on the forming method of cycloid gear’s tooth profile as well as the efficiency and accuracy requirement of machining,the relevant design research of several main parts of the WEDM special tool’s structure are carried out,which provides a new way to solve the problem of machining cycloid gear.