Abstract: A launch device for a vehicle transmission including a housing, an impeller, a turbine, and first and second clutches with first and second pistons, respectively. The first and second pistons are sealingly engaged with one another. The first clutch releaseably engages the impeller with the housing and the second clutch releaseably engages the turbine with the housing. In an example embodiment, the first clutch is disposed radially outside of the second clutch. In an example embodiment, the first clutch is engaged by a first pressure, and the second clutch is engaged by a second pressure greater than the first pressure.

Abstract: A power transmitting apparatus for transmitting power from a driving source of a vehicle to its wheels can be adapted to properly select transmitting or cutting-off of the driving force of the driving source to or from the wheels. The apparatus can comprise a torque converter having a torque amplifying function; a clutch mechanism including a first clutch device operable on advancement of the vehicle and adapted to transmit the driving force of the driving source to the wheels through a power transmitting system of the torque converter and a second clutch device adapted to transmit the driving force of the driving source to the wheels without the power transmitting system of the torque converter. A selecting device can be configured to operate the first clutch device and/or the second clutch device in accordance with operation modes of the vehicle, including starting.

Abstract: A piston assembly for arrangement in a pressure cavity in a force transfer device for operating a first and a second actuatable clutch device, comprising a piston element associated respectively with an actuatable clutch device. The invention is characterized in that the piston element of the second clutch device is guided at the piston element of the first clutch device movable against a stop, forming an additional second cavity, loadable with pressure medium, wherein the first piston element is movable in an axial direction, relative to the piston element of the second clutch device.