Analysis Of Five-Axis End-Milling Machining Of Cycloidal Gear And Its Precision

Methods of peripheral milling and end milling are applied to CNC machine of parts using the cylindrical milling cutter.The cutting edge of peripheral milling is on the cicumference of the tool,which makes the tool easily be broken and deformed when machining the high thickness and hardness parts,especially the curved surface with large curvature changes.In contrast,the cutting edge of end milling is on the outer arc of the tool,which can make full use of the advantages of the tool,like maximum cutting speed,stable cutting force and lower cutter shaft deformation,especially when changing the tool inclination,the working surface of the tool can match the surface of the machined parts better and adapt its curvature change well.In order to simplify machining process,reduce production costs,improve processing efficiency and processing quality,with the support of National Natural Science Foundation "Research on Mechanism and Key Technology of Five-Axis End-Milling of Cycloidal Gear without Over-cut” and the Fund of “Precision Cycloidal Gear Reducer ofRobot” of Shanxi Ying Rui Ke Automation Co.,Ltd,this paper proposes a machining method of cycloidal gear that is End-Milling.The main research contents are as follows:(1)The mathematical model of the tooth profile of cycloidal gear was built using the method of coordinate transformation and conjugate principle of the space curved surface.Then the 3D model of cycloidal gear was established using the CREO 3D modeling software.(2)The processing track without interference of end milling of cycloidal gear was got,through determining the processing way of feeding,track spacing,calculating cutter location and tool orientation feasible region.(3)The processing technics of cycloidal gear was designed and its NC codes was programmed with powermill automatic programming software,especially the five-axis programming of tooth profile finishing.(4)Four factors and four levels orthogonal experiments was designed to study the order and significant level of cutter shaft inclination angle,feed per tooth,radial feed rate and spindle speed on the surface roughness of cycloidal gear using methods of range and variance.(5)A model to predict the surface roughness is created based on the probability statistics and multivariate nonlinear regression analysis.Significance tests were conducted on the prediction model,and then figured out the interaction effect of these parameters on the surface roughness,and thus to propose optimization schemes.(6)The accuracy of the whole tooth profile of cycloidal gear was analyzed and measured using HEXAGON image measuring instrument.