Patent ID: 8857587

Claim:
A method for operating an open 3-line type hydrodynamic coupling device, the hydrodynamic coupling device comprising: a housing arrangement that is one of filled with a fluid or fillable with a fluid; an impeller that is rotatable with the housing arrangement around an axis of rotation; a turbine arranged in the housing arrangement and coupled with a driven member for rotation around the axis of rotation; a lockup clutch that selectively produces a torque transmission connection between the housing arrangement and the driven member, wherein the lockup clutch comprises: a clutch piston dividing an internal space of the housing arrangement into a first space containing the turbine and a second space, wherein the first space and the second space are in fluid communication with one another at least when the lockup clutch is disengaged, a first fluid channel leading to the first space; a second fluid channel leading to the first space, wherein the fluid can be supplied to the first space via at least one of the first fluid channel and the second fluid channel and the fluid can be removed from the first space via at least one of the first fluid channel and the second fluid channel; and a third fluid channel configured to at least supply the fluid to the second space, the method comprises: displacing the clutch piston by a first fluid pressure in the engaging direction, the first fluid pressure provided in the first space for engaging the lockup clutch; displacing the clutch piston in the disengaging direction by a second fluid pressure provided in the second space for disengaging the lockup clutch; adjusting at least one of a fluid supply pressure for the first space and a fluid supply pressure for the second space based at least in part on at least one operating variable: in the engaged state of the lockup clutch and in the disengaged state of the lockup clutch and for engaging the lockup clutch and for disengaging the lockup clutch, wherein the at least one operating variable comprises at least one of: a temperature in the region of the coupling device, a fluid temperature in the region of the coupling device, and a loading of the coupling device in torque-transmission/conversion operation wherein when the lockup clutch is disengaged the fluid supply pressure for the second space is adjusted to a higher value when at one of a higher temperature and higher load than when at one of a lower temperature and lower load.