Performance Analysis And Modification Design Of Hypoid Gears

Hypoid gears are the key part of the vehicle drive axle main reducer,their meshing performances,service life and reliability have the vital influences on the vehicle safety.This paper bases on the theory of gearing and differential geometry,studied the meshing performance of hypoid gears by means of theoretical TCA and Ease-off-TCA method.Based on the finite element grid automatic division and accurate assembly method of gear pairs,achieved batch processing for finite element analysis by the inp file in ABAQUS,and through the tool modification design to improve the meshing performance of gear pairs,provided some reference for the design and application of hypoid gears.Content of this paper are as follows:(1)Based on the theory of gearing and differential geometry,established the accurate model of hypoid gears tooth with transition fillet.The solid model of hypoid gears are established by means of the cutting tooth simulation method and the reverse modeling method,and the two modeling results are compared.The results show that the model by cutting tooth simulation method is better and the accuracy of the mathematical model of the gears is verified.(2)Based on the mathematical model of hypoid gears,the Tooth Contact Analysis of hypoid gears is studied,its meshing mark and transmission error are got.Based on the conjugate tooth surface of pinion,studied the principle of Ease-off-TCA.The advantages and disadvantages of the theoretical TCA and Ease-off-TCA are compared,and the accuracy and feasibility of Ease-off-TCA are verified.The influence of the installation error on the meshing performance of gear pairs is analyzed,the results show that there is a regular relationship between the tooth surface contact area and the gear mounting error.(3)The finite element grid automatic division and TCA-based finite element model precise assembly method of gear pairs is adopted,achieved batch processing for finite element analysis by the preparation of inp file.The influence of different load and installation error on the strength of the hypoid gears is studied,the results show that under the effect of installation error,stress is maximum when the tooth is in small end contact and stress is minimum when contact in the middle of the tooth.(4)In order to further improve gears performance,the surface of pinion is modification designed by using the curved blade to replace the line blade.With the transmission error,position symmetry and coincidence degree as the optimization target,the tool design parameters were optimized by NSGA2 multi-objective optimization algorithm.The influence of transmission error design on the tooth root bending stress and the tooth surface contact stress is studied.The results show that the transmission error mainly affects the maximum tooth surface contact stress,the greater the transmission error.