Analysis And Optimization Of NVH Performance Of A Certain Type Of Reducer

Reducer is a important part of the drive line system,it has a direct impact on the car’s stability and comfort.As the rising demand of passenger cars year by year,for the pursuit of comfort,reducer with good performance is more and more popular with the consumers.As a kind of power transmission mechanism,reducer makes use of gear’s speed converter,reduces the number of the motor’s rotations to the required number of rotations,the fuel economy is improved and the unstability of transmission’s performance is reduced.And the long term accumulation of machining capacity and human resources on the mechanical transmission industry can be fully used and in a long time,it will be the most promising in China.Under the background of advocating independent research and development on China’s automobile industry,it’s paticularly important to analyze various aspects of the reducer.In this paper,the research object of the project is a reducer which comes from a Vehicle Technology Develoment Co.,LTD of Chong Qing, by using finite element theory and simulation,constraint modal and free modal of the reducer’s shell are analyzed,the weak parts of the shell are found out and optimized,the dynamic excitation and the dynamic response are analyzed.Alternate method is applied to predict the vibration acceleration response of any code’s XYZ directions of the reducer,finally,study the gears from microcosmic,a optimization scheme is proposed,the vibration and noise is reduced with the transmission error reduction. Paper main research work and innovation are as follows:(1)The geometric model,finite element model and simulation model of the reducer are established, the free modal,constraint modal and strain energy are analyzed,the vulnerable spot of the shell is optimized.(2)Dynamic mathematic model of the reducer’s drive system is established by applying Machinary Dynamics and Gears System Dynamics.The modals of the reducer’s shell and gear transmission system are analyzed by using alternate method,the natural frequency and vibration gained,based on which,the range of resonance frequency of the gear transmission system is analyzed emphatically and provide theoretical basis for gear profile modification and optimization of the gear transmission system.(3)The transient response of the reducer’s gear transmission system is analyzed by using Romax software,the vibration quantity of the gear drive system under different frequencies are obtained,on the basis of which,gear profile modification is made to achieve the aim of making the gear drive system more stable,reducing gear noise and improving the NVH performance.