Efficiency-optimised CVT hydraulic and clamping system

An important target of modern transmission technology is the reduction of fuel consumption. The AUDI multitronic(R) currently in production with the LuK CVT components: pulley sets, chain, hydraulic control unit with pump and damper sets a very good standard with regard to efficiency, fuel consumption and dynamic behaviour. Compared to conventional 5 speed automatic transmissions there is a fuel consumption advantage of 9 %, and the time for acceleration from 0 to 60 mph is improved by 1.3 s. These values are mainly influenced by the CVT components delivered by LuK as a system supplier. Further developments of the hydraulic control, in combination with new ideas for a slip controlled clamping, show a potential to reduce fuel consumption. The benefit of the described concept including the LuK chain amounts to 7 ... 10 % compared to conventional CVT technologies.