Abstract
This paper describes the details of a new traction drive transmission, which features a self-loading mechanism to achieve high efficiency and a simple ratio-change system without synchronizers. An accurate model of the dynamic behavior of this transmission was constructed and tests using components or an assembly were executed to analyze power transmission efficiency and ratio-change performance, which are fundamental attributes of transmissions. An analysis of power transmission efficiency based on calculations and measurements confirmed that this transmission has a high potential, achieving high efficiency equal to that of gears while the power transmission unit generates less heat than gears. Ratio-change performance was investigated using a kinematic model consisting of kinematic equations of the rollers, including the translational motion that is characteristic of this mechanism, and ratio-change logic for controlling clutch operations so as to decrease heat generation on the rollers and achieve smooth ratio changes. Bench test results showed that the ratio-change logic operated correctly.
