Usui, T., Okaji, T., Muramatsu, T., and Yamashita, Y., "Development of a Compact Ultra-Flat Torque Converter Equipped with a High-Performance Damper," SAE Int. J. Engines 8(3):1374-1378, 2015, doi:10.4271/2015-01-1088.
By optimizing parameters related to damping performance and adopting a layout that incorporates the turbine into the damper components, a “Turbine Twin-Damper” lock-up damper was developed that achieves both damping performance and compactness. To reduce losses in the fluid flow channel, a smaller torus was developed that reduce the width of the torus by about 30%.Through the combination of this Turbine Twin-Damper and smaller torus, attenuation of the torque fluctuation transmitted to the transmission to 1/2 or less compared to a conventional product was achieved without increasing the overall width of the torque converter. As a result, the engine speed at cruise fell by 400rpm, and fuel economy improved.