Simulation Analysis On Meshing Performance Of Harmonic Gear Based On Multi Stage Modification Profile

Harmonic reducer is a kind of high precision transmission mechanism,it is widely used in the industrial field.The optimal design of the tooth profile of harmonic reducer is always a hot research issue to improve its transmission performance.In this paper,the characteristics and characteristics of different tooth shapes of harmonic reducer were summarized and analyzed.According to the change characteristics of "involute → double arc →S tooth profile→P tooth profile" and the characteristics of profile,the multistage modified profile curves were constructed by using the manufacturing deviation grade of profile and the principle of gear modification.And through the construction of multistage modified tooth shape harmonic reducer three-dimensional model,finite element simulation and TCA analysis method were used to conduct meshing simulation analysis of tooth profile models with different deviation curves.According to a series of simulation results,the thought of tooth profile optimization design was put forward.The main works completed in this paper are as follows:(1)The characteristics of different tooth shapes of harmonic reducer and their relationship were analyzed.Combining with the standard documents of manufacturing precision of harmonic reducer,the graded tooth profile deviation curve was constructed.The characteristics of several tooth profiles and the changes among tooth profiles were analyzed and summarized.The gear profile modification thought of ’involute→double arc→S tooth profile→P tooth profile’ was determined as the reference,and the profile modification curves of different modification categories as well as amounts were constructed.According to the tolerance modeling theory,a certain type of harmonic reducer was selected,and the dimension parameters were calculated according to the relevant parameters and formulas.The three-dimensional deviation models of different modification categories and tooth modification quantities were established in CREO6.0 software.(2)The finite element analysis environment of harmonic reducer was built in the finite element analysis software ANSYS.The tooth profile model and deviation model constructed above were successively imported,and the contact stress analysis was carried out by using the finite element method.The contact stress distributions of different tooth profile deviation models were obtained by simulation experiments.(3)TCA analysis was carried out on the model of harmonic gear reducer with multi-level modified tooth profile,the actual contact area size of different levels of modified tooth profile was calculated and plotted,and the change trend of contact area of different levels of modified tooth profile was analyzed.(4)Matlab was used to write a simulation program to calculate the clearance size ofdifferent tooth profile deviation models.Through the simulation results,the differences of the mesh clearance were obtained,and the comparison and evaluation were made.(5)According to the results of simulation analysis,based on the involute tooth profile,the tooth root and tooth tip are modified by arc.With the increase of modification amount,the maximum contact stress of harmonic reducer gradually decreases,the contact area gradually increases,the meshing clearance gradually decreases,and the meshing performance gradually improves;However,with the modification of the tooth root,the stress contact performance becomes stronger and the contact area becomes larger,and the meshing performance has a trend of further improvement.At the same time,the meshing clearance becomes larger,which leads to the meshing impact becoming larger,resulting in the transmission instability.Therefore,in the actual design and manufacturing,we should select the appropriate amount of modification to optimize the design of tooth profile.In this paper,based on the simulation results of three-dimensional deviation models of different modification categories and tooth modification quantities,the meshing performance of the established tooth deviation models was comprehensively evaluated,and the tooth profile optimization was proposed accordingly.This method not only explores the influence of tooth profile deviation on meshing performance,but also provides a new idea and basis for the repair design of harmonic reducer.