Reliability Research Of Key Parts For Automotive Clutch On The Basis Of Typical Roads

The clutch is a key part of automotive, which has an effect on safety and comfort of automotive. Furthermore, the gear hub assembly is a crucial part of the clutch. During very bad working environment and complex load situation, the reliability of the automotive is ensured by the security and fault-free operation of gear hub assembly. In the process of automobile driving, fatigue damage is caused by the dynamic loads, which causes the fatigue failure. In the paper, the reliability research of the key parts of the automobile clutch is carried out under typical roads conditions, which covers four aspects, including the p-S-N statistics, load spectrums, fatigue life prediction and reliability analysis.The main contents of this paper is stated as follows:(1) According to the requirements of the enterprise, static strength tests and torsional fatigue tests of the clutch hub assembly are allpied for life prediction and reliability analysis. On the basis of torsional tests, the Weibull Distribution is adopted to fit fatigue life data, and the parameters of Weibull Distribution are determined by applying the maximum likelihood estimation. The data dispersion of small sample is discussed based on the confidence, and p-S-N curves of specimens are formed under the different survival rate, by which the foundation are well laid for the subsequent fatigue life prediction and fatigue reliability analysis.(2) The data of typical roads of the proving grand is gathered by using six component measuring apparatus. Then outlier screening, signal denoising and low amplitude loads filter of load spectrum are completed. The load spectrum of clutch hub assembly is determined by establishing load transmission line. The rainflow counting is carried out based on the load spectrum. According to the rainflow matrix, one- and two-dimensional program load spectrums are both constructed based on the extrapolated load data, which provide technical basis for fatigue life prediction.(3) By applying the methods of counting method and probability method respectively, the gear hub assembly fatigue life is estimated based on the Miner linear cumulative fatigue damage theory, the p-S-N curves and one- and two-dimensional test programed load spectrums. By comparing the results, the advantages and disadvantages of each method are discussed, which provide reference for other similar studies.(4) The equation of fatigue reliability is established based on the cumulative fatigue damage probability model. The relation curve of the fatigue reliability and durability mileage of gear hub is determined, and the fatigue reliability of key parts gear hub assembly is discussed under certain reliability.The innovation of this paper is mainly reflected in the following ideas:Based on the bench test, the fatigue characteristics of the parts are studied, and the fatigue life prediction and reliability analysis are completed by using the fatigue damage theory, which lay the foundation for the design and development process of the parts.Above all, the technical foundation of lightweight design and fatigue life prediction of the gear hub are laid, and references can be provided for reliability and durability evaluation of key parts of automotive transmission system.