The invention relates to a method for adjusting a friction coefficient of an automated clutch, wherein a current friction coefficient (RK) is determined by a comparison with a moment of the internal combustion engine during a slipping phase of the clutch. In a method, in which the adaptation over the entire operation of the motor vehicle is possible, the current friction coefficient (RK) is pilot-controlled to a long-term friction coefficient (RL) in a non-slipping phase of the clutch and/or in the event of a torque signal that cannot be monitored.

The present disclosure relates to a method and an apparatus for controlling a lubricant flow rate in a wet clutch. The method comprising: determining a clutch state as an open state, a closed state or a slipping state; determining a clutch temperature and a sump lubricant temperature; based at least on the clutch state, the clutch temperature and the sump lubricant temperature, selecting one out of a plurality of maps, wherein each map maps one or more operating parameters of the clutch on a target lubricant flow rate; determining a target lubricant flow rate based on the one or more operating parameters according to the selected map; and controlling a lubricant flow control device based on the determined target lubricant flow rate.

The present invention relates, inter alia, to a method for regulating the engagement position of a position-controlled clutch unit for a drive train of a motor vehicle. The clutch unit has at least one wet-running friction clutch for the controllable transmission of a torque from an input element to an output element and an actuator for setting the engagement position for the purposes of mutual compression of the input and output elements. The method compensates a time-dependent setting behavior of the friction clutch on the basis of the uptake of lubrication oil of the friction clutch, which varies over time, in that the engagement position of the clutch unit is regulated by means of the actuator as a function of the time-dependent setting behavior.

The present invention relates, inter alia, to a method for regulating the engagement position of a position-controlled clutch unit for a drive train of a motor vehicle. The clutch unit has at least one wet-running friction clutch for the controllable transmission of a torque from an input element to an output element and an actuator for setting the engagement position for the purposes of mutual compression of the input and output elements. The method compensates a time-dependent setting behavior of the friction clutch on the basis of the uptake of lubrication oil of the friction clutch, which varies over time, in that the engagement position of the clutch unit is regulated by means of the actuator as a function of the time-dependent setting behavior.

A rear axle drive (2) for an AWD vehicle is presented. The rear axle drive (2) is connected to an hydraulic AWD coupling (3), wherein the rear axle drive (2) comprises a lubrication valve (4) for controlling the level of lubricant in at least one lubricant reservoir (6, 7) of the rear axle drive (2) for providing lubricant to gears and/or bearings of the rear axle drive (2). The lubrication valve (4) is functionally connected to a shut-off valve (5) of the AWD coupling (3) and the lubrication valve (4) of the rear axle drive (3) is controlled by movement of an actuating member (51, 54) of the AWD coupling (3).

Operating a clutch assembly of a vehicle drive train, the clutch assembly comprising a clutch with a clutch component that exchanges heat at least indirectly with a medium which is conducted at least partially in the clutch, comprises at least: a) determining an operating point parameter which is representative of a current operating state of the clutch; b) determining a first thermal property parameter of the medium, as a function of the determined operating point parameter; c) determining a second thermal property parameter of the at least one clutch component; d) calculating a component temperature of the at least one clutch component as a function of at least the following three values: a further component temperature of a further clutch component, the first thermal property parameter, and the second thermal property parameter; and e) adapting activation of the clutch as a function of the calculated component temperature.

The present disclosure relates to a method and an apparatus for controlling a lubricant flow rate in a wet clutch. The method comprising: determining a clutch state as an open state, a closed state or a slipping state; determining a clutch temperature and a sump lubricant temperature; based at least on the clutch state, the clutch temperature and the sump lubricant temperature, selecting one out of a plurality of maps, wherein each map maps one or more operating parameters of the clutch on a target lubricant flow rate; determining a target lubricant flow rate based on the one or more operating parameters according to the selected map; and controlling a lubricant flow control device based on the determined target lubricant flow rate.

The invention relates to a method for adjusting a friction coefficient of an automated clutch, wherein a current friction coefficient (RK) is determined by a comparison with a moment of the internal combustion engine during a slipping phase of the clutch. In a method, in which the adaptation over the entire operation of the motor vehicle is possible, the current friction coefficient (RK) is pilot-controlled to a long-term friction coefficient (RL) in a non-slipping phase of the clutch and/or in the event of a torque signal that cannot be monitored.

A rear axle drive (2) for an AWD vehicle is presented. The rear axle drive (2) is connected to an hydraulic AWD coupling (3), wherein the rear axle drive (2) comprises a lubrication valve (4) for controlling the level of lubricant in at least one lubricant reservoir (6, 7) of the rear axle drive (2) for providing lubricant to gears and/or bearings of the rear axle drive (2). The lubrication valve (4) is functionally connected to a shut-off valve (5) of the AWD coupling (3) and the lubrication valve (4) of the rear axle drive (3) is controlled by movement of an actuating member (51, 54) of the AWD coupling (3).

Operating a clutch assembly of a vehicle drive train, the clutch assembly comprising a clutch with a clutch component that exchanges heat at least indirectly with a medium which is conducted at least partially in the clutch, comprises at least: a) determining an operating point parameter which is representative of a current operating state of the clutch; b) determining a first thermal property parameter of the medium, as a function of the determined operating point parameter; c) determining a second thermal property parameter of the at least one clutch component; d) calculating a component temperature of the at least one clutch component as a function of at least the following three values: a further component temperature of a further clutch component, the first thermal property parameter, and the second thermal property parameter; and e) adapting activation of the clutch as a function of the calculated component temperature.