Study On Design Method Of Continuously Variable Transmission With Reflux Power

Continuously variable transmission (short as CVT) with reflux power is super wide in ratio coverage and rather high in transmission efficiency. Moreover, it can continuously regulate speed in its ratio coverage, which leads to engine works at optimum fuel economy curve all along. Therefore, CVT with reflux power will be very promising for research and application.Carried out by national natural science foundation (NNSF) and new century talents support planning project, design method for the system of CVT with reflux power has been studied in this paper. The main contents are following.1 On the purpose of improving efficiency of continuously variable transmission with reflux power, efficiency of previous system under low gear and reverse gear have been analyzed to optimize its structure based on analysis of speed modulation characteristic and transmission efficiency of transmission system. What's more, with maximum speed ratio, minimum speed ratio of transmission system and speed ratio of reverse gear having been calculated, design method of structural parameters has been brought out. Finally, SC7101 as reference, design on structural parameters of continuously variable transmission with reflux power has been presented on the base of performance of previous structure.2 The mechanical analysis for the rings and blocks in the mechanism of metal push belt continuously variable transmission has been done with given structure parameters. Then, the expressions for axial force on driving wheel and driven wheel have been derived. Finally, the maximum axial forces on driving wheel and driven wheel have been obtained and the effects caused by them also have been analyzed.3 Based on the diagrammatic sketch for transmission system, the structure drawing has been drawn, in which the clutch, the brake, constant ratio gears, planet gears, the double-geared drive and so on are all designed according to the results obtained in above paragraph. Some problems that should be care during the design of clutch have been analyzed, and then gears and shafts are all checked in the paper.4 On the purpose of comparison between CVT with reflux power and metal push belt continuously variable transmission and dual-state continuously variable transmission, the simulation models for such three different CVT have been built, with which the advantages of CVT with reflux power were found contrast to the other two...