Theoretical And Experimental Research On Pulley Thrust Balance Of Metal V-Belt CVT

With the development of automotive technology and the continue increase of people on vehicle fuel economy and comfort requirements, the role of transmission is not only to meet the start, reverse, shift and other basic needs anymore. Transmission’s performance in vehicle fuel economy, driving dynamics, emission performance, driving comfort is getting more and more attention. Compare with various types of transmissions, the metal v-belt continuously variable transmission has become the focus of automotive companies and research institutions because of its advantages such as realize continuous speed change of vehicle.The speed ratio control in the control of the metal v-belt continuously variable transmission has the influence on the economy, the power and the comfort of vehicle with the comfort and accuracy of stable speed ratio control. Commonly used speed ratio control method, the speed ratio feedback control has a limited control effect if the ratio error is too large, this disadvantage leads to a decline in the performance of vehicle control. In this paper, the thrust balance model between the primary pulley and the secondary pulley of metal v-belt CVT is proposed. This model can be used as part of feed-forward control or model-based control in speed ratio control model, which can effectively eliminate the speed ratio error and the speed fluctuation and improve the efficiency and reliability of the speed ratio control system.In this paper, the following research is carried out in the research of the thrust balance between primary pulley and the secondary pulley of the metal v-belt CVT:1. Set up the model of the thrust balance between primary pulley and the secondary pulley of the CVT. Combined with the structure, working principle and power transmission mechanism of the metal v-belt CVT, the force analysis of the metal belt is carried out. A math model of the thrust balance between primary pulley and the secondary pulley is developed through mathematical calculation. Then, analysis the factors affect the thrust ratio between primary pulley and the secondary pulley.2.Set up a test bench of the thrust balance between primary pulley and the secondary pulley of the CVT. In this paper, the experimental object is a domestic independent researched and developed CVT. Matching power system and test system with the selected CVT. Set the calculated thrust balance model as the basis for the analysis, and set the factors like the speed ratio, the input torque of primary pulley, the torque ratio of transmission, the input speed of primary pulley and other factors as variables. Set up kinds of test conditions to do the test.3.Compare the analysis result of the theoretical model of the thrust balance between primary pulley and the secondary pulley with the analysis result of the experimental. Deal with the data measured from the test bench. Compare with the analysis of the theoretical model, analysis the test results in different conditions to analysis the impacts of different experiment variables on the thrust balance between primary pulley and the secondary pulley of the CVT.