Analysis and Testing for Slip Characteristics of Artificial Hydraulic Circuit based Push-Belt Continuously Variable Transmission

Applying a Continuously Variable Transmission (CVT) in an automotive driveline has several advantages. A CVT can operate at a wider range of transmission ratios, therefore the engine can be operated more efficiently than with a stepped transmission. The present research focuses on the influence of loading conditions on the slip behaviour and torque transmission of the CVT. The CVT model is developed to investigate the range of clamping forces needed to initiate the transmission and to successfully meet the oil pressure requirements. An analytical approach is used to calculate the possible transmission efficiency and traction coefficient of the push belt CVT. The experimental setup and the instrumentation are presented in detail. The measured results are presented in more detail for the V-belt type variator and oil pressure reapplication by a separate hydraulic unit and reduction ratio of CVT.