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The metal pushing V-belt of a CVT equipped with a torque converter receives a sudden thrust load from the pulley when the CVT starts operation, and is required to begin transmitting torque from a stationary state with minimal time lag. In this study, the stress history of the area around the element neck under transient driving condition was clarified using new structural analysis technology to simultaneously simulate the dynamic behavior of the metal pushing V-belt and the element stresses. These results suggest that the compression stress generated by the load on the element V-surface is a fundamental component of element stress, and that bending stress generated by the compression force between the elements is superimposed on this stress. A comparison of simulation results with test results for the load distribution on the element, conducted to confirm the accuracy of the simulation, demonstrated good qualitative correlation.

A newly developed 1.3L, 1.5 L class CVT with a torque converter was mounted in the second generation FIT, which is aimed at realizing both higher fuel economy and exhilarating acceleration performance. As the main technologies used in the new CVT, a torque converter was used for a start-off method, an oil pump driven with small radius rotors via a chain and a structure with the bearing was mounted on the drive pulley cover. Particularly, as a type of fuel economy enhancement technology, the distance between two pulleys was increased, thus reducing friction torque. Also, creep control was used to enhance idling fuel economy, and start-off lockup clutch control was used to enhance launch fuel economy. As a result of these technologies, the transmission efficiency was 1.7% higher than that of the previous FIT CVT, and torque amplification effect of the torque converter during launch enabled achievement of higher fuel economy and exhilarating acceleration performance.