Deformation Analysis And Control Of Five-Axis NC Machining Of Small-Scale Planar Double-Enveloping Hourglass Worm Gear Drive

Due to the advantages of multi tooth line contact and good lubricity condition,planar double-enveloping hourglass worm gear drive is widely used in the fields of mechanics,aviation,military and so on.Because of the complexity of the enveloping surface,the 3D model of the planar double-enveloping hourglass worm gear drive is of low precision,and the precision machining of the enveloping surface is usually done by the grinding method,and the efficiency of the grinding process are low.Therefore,how to build planar double-enveloping hourglass worm gear drive of 3D precision model,vice reasonable process and five axis NC machining deformation control method are important tasksto realize the planar double enveloping hourglass worm gear drive with the high precision and high efficiency machining.For the reason mentioned above,this paper comprehensively uses the theory of multi axis NC machining,numerical simulation technique to research the deformation regularity of the tooth profile of small-sized planar double-enveloping hourglass worm gear drive of five axis NC machining and to explore planar double-enveloping hourglass worm gear drive of five axis NC machining parameter optimization method.Specifc research work is as follows:1)Establishment of precise 3D model.The precise digital CAD model is established by means of vector method,transfer matrix,spatial meshing principle and envelope principle,which lays the foundation for the five axis NC machining later.2)Planning NC machining process for small-sized planar double-enveloping hourglass worm gear drive vice with five axes.Through the analysis of characteristics and the processing methods of small-sized planar double-enveloping hourglass worm gear drive structure,the five axis NC machining tool path planning scheme is established.The examples of tool path plan are analyzed by using UG8.0 software CAM module,and the simulation of machining parts are carried out by using VERICUT software to verify the correctness of the tool path planning at the same time.3)The error analysis of the five axis NC machining and the prediction of the machining deformation of the small planar double-enveloping hourglass worm gear drive.By means of orthogonal test,the milling force of tooth profile finishing under different machining parameters is obtained.The milling force of tooth profile finish machining,milling force prediction model were established by using the regression equation,and the example of established milling force model is compared and analyzed.The ANSYS software is used to predict and analyze the error of the five axis flank milling of the small-sized planar twoenveloping hourglass worm gear.4)Multi-objectiveoptimization of milling parameters.Taking the milling parameters as design variables,the milling force and the maximum material removal rate as the optimization goal,combined with the constraints of each parameter to establish the multi-objective optimization function of milling parameters.The optimization of cutting parameters in machining process based on particle swarm algorithm,so as to realize the control of the machining error and to achieve the small-sized planar double-enveloping hourglass worm gear drive the high precision and high efficiency machining.In summary,this study not only provides a effective resolution for the effect of milling force on machining deformation of small-sized planar double-enveloping hourglass worm gear drive in five axis CNC high precision machining,but also provides an effective scheme for the five axis NC machining of the high efficiency and high precision machining of small-sized planar double-enveloping hourglass worm gear drive.