Synchronizer Design And Development For Wet Dual Clutch Transmission (DCT)

With the growth of economic and development of automotive technology, Automatictransmission is used widely in the automobile. Because the dual-clutch automatictransmission has compact structure and high transmission efficiency, which can improvevehicle fuel economy effectively, its market share increase gradually year after year.Because the working condition of synchronizers for wet dual-clutch transmission is moreserious, which bring great synchronizer technology challenge. Therefore, taking thesynchronizer of wet dual-clutch automatic transmission as the research object, the basictheory, design methods, performance optimization and test method of synchronizer for wetdual-clutch automatic transmission was studied in this paper.First of all, the basic theory of synchronizer was studied,which include the basicprinciples and work process of synchronizer. The dynamic of synchronizer was model. Andalso the structure of kinds of synchronizers and characteristics of synchronizer for wetdual-clutch automatic transmission were studied.Secondly, on the basis of theoretical research of synchronizer, the mathematical modelof synchronizer for wet dual-clutch transmission was established. The design methods ofsynchronizer for the wet dual-clutch transmission was described in detail.Taking alongitudinal7-speed dual-clutch transmission synchronization wet as a example, thestructure and main parameters of the synchronizer were determined.Thirdly, the impact of locking angle, cone angle, friction materials and major gaps andother parameters on the performance and durability of synchronizer were analyzed based onthe mathematical model of synchronizer for a wet dual-clutch automatic transmissionsynchronizer. The synchronizer optimization was modeled and the performance anddurability of the synchronizer mentioned in this paper is optimized.Finally, according to the shift characteristics of wet dual-clutch automatic transmission,the synchronizer performance and durability test-bench was built and the test methods wasdeveloped. The performance and durability of the synchronizer is validated and therationality of the synchronizer design model and optimization model established in this paperwas also validated.Through the research on synchronizer for wet dual-clutch automatic transmission, the synchronizer design method was proposed. The possible failure mode for synchronizers isanalyzed, and then the effective and feasible solutions were proposed which have greatsignificance on the development of synchronizers and the improvement of the performanceand durability of synchronizers.