Design Optimization Of Rear Axle Gear Of Vehicle

Hypoid gear is a kind of gear transmission that is widely used in the rear drive axle.It can provide wide transmission ratio,high load capacity,smooth transmission,and low noise.As microcars evolve,customers have higher requirements for the comfort of vehicles,and OEMs are also asking for better NVH performance of the rear drive axle.The transmission noise of the gear of the rear axle main reducer is an important index to evaluate the quality of the rear axle,and the noise is also one of the main fault modes of the gear,so it is very important to control the gear noise.Transmission error and contact mark are the main factors that determine the gear noise.When the rear axle assembly is designed,the contact mark under the loading condition of the system support rigidity is considered.The optimal design of the gear tooth profile and the manufacturing process are the key technical problems that need to be solved urgently in the development process of the rear axle.This paper comes from a rear axle development project of Sichuan Jian ’an Company.Through the research of this project,the influence of main reducer support rigidity on rear axle gear transmission error,LTCA,NVH performance and other characteristics is grasped,so as to provide data support for lower noise gear design.The main contents of this research thesis are:1.Analyzed briefly from the aspects of gear design,manufacturing process and testing technology,and put forward the problems existing in the above aspects of Jian’an Company;2.By combining structural analysis,LTCA and NVH testing methods,the simulation analysis of support rigidity,transmission error and gear imprinting was carried out,and the correlation among support rigidity,transmission error,gear imprinting and rear axle NVH performance was verified through NVH testing,and the optimization objective was determined;3.The support structure of the gear was optimized by using the above methods,and the support rigidity indexes of the optimized gear were improved by 13.2-57.8%compared with the initial scheme;Compared with imported gear △α about 21.1-29%;△ E was about 4.2-8.7% lower;△ G was about 12.3-17.6% lower;△ 4 and 5grades are about 57.6-60.2% lower.The LTCA was further optimized based on the optimized support rigidity,and the transmission error was reduced by 33.8-58.3%.The ideal imprint shape was obtained,and the final modification optimization scheme was determined;4.Improved the original gear back adjustment process to solve the noise problem in the initial scheme and the high speed section;Full-speed section is equal to or better than the imported gear,the minimum is 13 d B lower than the imported gear.Through the whole vehicle NVH test and repeated test,the optimization effect of gear was verified,and it was extended to other products of the company,and a new gear design specification and gear development process was established;...