US Patent 7490526 Dual clutch powershift transmission with transfer shaft

A dual-clutch powershift transmission for use in a motor vehicle having an engine and a driveline includes an output shaft adapted for connection to the driveline, first and second input shafts, a first engine clutch operable for establishing a releaseable drive connection between the engine and the first input shaft and a second engine clutch operable for establishing a releasable drive connection between the engine shaft and the second input shaft. A first constant-mesh gearset is driven by the first input shaft. A second constant-mesh gearset is driven by the second input shaft. A first shift clutch releasably engages the first gearset to establish a drive connection between the first input shaft and the output shaft. A second shift clutch releasably engages the second gearset to establish a drive connection between the second input shaft and the output shaft.