There are many ways to improve the efficiency of double clutch transmissions* (DCTs). Increasing the number of gears is a well known one. Clutch losses can be reduced e.g. by using dry clutches instead of wet clutches. The actuation system losses can be reduced by using electromechanical actuation or by new hydraulic powerpack solutions. Hybridization and powertrain management software algorithms, oil management and reduction of bearing friction and other dissipation losses in the mechanical part are a list of possible ways to improve the efficiency of a DCT. This paper will introduce a new approach using newly developed full servo synchronizers.
The key component for that approach is a self-energising synchronizer, which can reduce the actuation energy significantly. These systems use basically the same effect as self-energising brakes (e-brake) and self-energising clutches as used in all wheel drives.
|08-12-03_CTIsymposium_hoferpowertrain_Hackl.pdf||Efficiency- cost and weight potential through reduced line pressure in DCTs with servo synchronizers|