| Transmission is the most important automobile transmission parts, and transmission system as a subsystem of chassis on the vehicle's power, economy and comfort has an important influence. Traditional transmission shift frequently during the car driving the will lead to driver fatigue, and a level transmission caused by the impact of shift also affect comfort. CVT is a transmission device, means under its control system, the system is unchanged in the case of the input speed, output shaft speed can be achieved within a certain range continuously change to adapt to the changing needs of the load. As the continuous development of technology industry, especially the automotive industry, the increasingly high demand for continuously variable transmission devices, but many domestic enterprises research institutions in the CVT with less experience and the lack of mature and reliable dynamic model and optimize the design and analysis methods. Therefore, trying the approach of building the dynamic modeling of metal V-belt type CVT and dynamic analysis have its great significance for practical applications.This paper studies the history and development of domestic and international status of the CVT, analysis of other structural features of CVT, and the advantages and disadvantages of CVT are described. Brief CVT in which the mechanical structure and role of the various components, and the analysis shows that the metal belt type continuously variable transmission of the basic theory and principle. To analyze the CVT based on the basic geometric relationships, get the formula of the metal band with long, tapered round corners, changes of speed ratio and the ratio and described the CVT drive the movement of relations. On the CVT tension of the metal band analysis, mechanical analysis of the piece of metal axial clamping force and torque transmission characteristics as a detailed analysis, also the clamping force and the speed ratio of factors, for the ADAMS model simulation parameters set the theoretical basis.In the modeling and analysis, the first application of solid modeling with powerful software features UG metal CVT reference entities in various parts of the size of geometric modeling, assembly, and the formation of virtual prototype, and to verify the design program is reasonable, some unreasonable to modify the parameters optimize the performance of the prototype model. Flexible metal band for its deal with this problem, we use the ANSYS finite element analysis software for processing, has been neutral flexible body file, import into the ADAMS model, it is more accurate simulation to ensure that the following were on the CVT the reliability of the dynamic simulation. ADAMS has been well-established model for the constraints and drivers for the relevant settings. Wrap angle in the cone round piece of metal and metal band at the speed of the analysis, the trend of the relative velocity, as previously verify the theoretical analysis. Often overlooked for the metal band ratio changes as a result of the offset is analyzed, conclusions drawn related simulation, and the inevitable losses that some optimization ideas.Finally, to sum up the work on their own to explore the design issues that may existed, and the next steps were discussed.
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