Patent ID: 7891473

Claim:
A torque converter for motor vehicles comprising a three-channel oil system and a lockup clutch, wherein: the lockup clutch includes at least two axially movable plates, at least one plate being non-rotatably connected to an outer plate carrier and at least one other plate being non-rotatably connected to an inner plate carrier; a first channel of the oil system is connected to a first space; a second channel operates the lockup clutch by pressurizing a second space of the torque converter with oil, thereby pressing a piston against the at least two axially moveable plates, one of the at least two axially moveable plates being closer to the piston and another of the at least two axially moveable plates being closer to the first space, the piston contacting the one of the at least two axially moveable plates being closer to the piston and moving the at least two axially movable plates in a direction away from the piston; an additional wall spaced apart from the piston is mounted on a side of the piston that faces the first space, whereby a gap is formed between the piston and the additional wall, the additional wall abutting in a substantially oil-tight manner against the closer one to the piston of the at least two axially moveable plates and at the same time providing hydraulic separation with respect to the first space and to the second space, thus forming a third space; the third space is connected in a substantially oil-tight manner to a third channel.