Dual-clutch Transmissions: Past, Present and Future
The man who invented the dual-clutch gearbox was a pioneer in automotive engineering. Adolphe Kégresse is best known for developing the half-track, a type of vehicle equipped with endless rubber treads allowing it to drive off-road over various forms of terrain. In 1939, Kégresse conceived the idea for a dual-clutch gearbox, which he hoped to use on the legendary Citroën "Traction" vehicle. Unfortunately, adverse business circumstances prevented further development.
Both Audi and Porsche picked up on the dual-clutch concept, although its use was limited at first to racecars. The 956 and 962C racecars included the Porsche Dual Klutch, or PDK. In 1986, a Porsche 962 won the Monza 1000 Kilometer World Sports Prototype Championship race -- the first win for a car equipped with the PDK semi-automatic paddle-shifted transmission. Audi also made history in 1985 when a Sport quattro S1 rally car equipped with dual-clutch transmission won the Pikes Peak hill climb, a race up the 4,300-meter-high mountain.
Commercialization of the dual-clutch transmission, however, has not been feasible until recently. Volkswagen has been a pioneer in dual-clutch transmissions, licensing BorgWarner's DualTronic technology. European automobiles equipped with DCTs include the Volkswagen Beetle, Golf, Touran, and Jetta as well as the Audi TT and A3; the Skoda Octavia; and the Seat Altea, Toledo and Leon.
Ford is the second major manufacturer to commit to dual-clutch transmissions, made by Ford of Europe and its 50/50 joint venture transmission manufacturer, GETRAG-Ford. It demonstrated the Powershift System, a six-speed dual-clutch transmission, at the 2005 Frankfurt International Motor Show. However, production vehicles using a first generation Powershift are approximately two years away.
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