A drive device for a motor vehicle includes an electric machine having a gearbox where the motor vehicle is drivable electrically via the gearbox by the electric machine. At least one gear of the gearbox is switchable by operating a switch element. A medium is flowable through a circuit that has a first branch through which the medium is flowable to cool and/or lubricate the electric machine and/or the gearbox and a second branch through which the medium is flowable to operate the switch element. A pump delivers the medium through the circuit. The medium is flowable through a third branch of the circuit to operate the parking lock.

A hydraulic system, in particular a hydraulic transmission controller, includes a first pump, which provides a large volumetric flow for a cooling and/or lubricating device at an outlet, and a second pump, which provides a high pressure for at least one hydraulic load at an outlet. The hydraulic system also includes an additional active valve, which is connected upstream of the cooling and/or lubricating device, is connected to a system pressure valve and to at least one hydraulic load to be boosted in such a manner that in a boost state, the outlets of the two pumps are connected to the hydraulic load to be boosted via a boost line.

A hydraulic system, in particular a hydraulic transmission controller, includes a first pump, which provides a large volumetric flow for a cooling and/or lubricating device at an outlet, and a second pump, which provides a high pressure for at least one hydraulic load at an outlet. The hydraulic system also includes an additional active valve, which is connected upstream of the cooling and/or lubricating device, is connected to a system pressure valve and to at least one hydraulic load to be boosted in such a manner that in a boost state, the outlets of the two pumps are connected to the hydraulic load to be boosted via a boost line.

Methods and systems for hydraulic actuation of axle system components are provided. A hydraulic system in an electric axle, is provided in one example, which includes a housing with a plurality of sections that enclose an electric motor and a gearbox, the system further includes a hydraulic pump that is coupled to the housing and configured to supply pressurized fluid to a solenoid valve through a plurality of fluid passages. The hydraulic system further includes a clutch in the gearbox configured to receive the pressurized fluid from the solenoid valve through a hydraulic passage internally routed through the housing.

Methods and systems for hydraulic actuation of axle system components are provided. A hydraulic system in an electric axle, is provided in one example, which includes a housing with a plurality of sections that enclose an electric motor and a gearbox, the system further includes a hydraulic pump that is coupled to the housing and configured to supply pressurized fluid to a solenoid valve through a plurality of fluid passages. The hydraulic system further includes a clutch in the gearbox configured to receive the pressurized fluid from the solenoid valve through a hydraulic passage internally routed through the housing.

A line pressure control method for a double clutch transmission (DCT) includes estimating a line pressure, which decreases with stoppage of an electric oil pump, based on a linear regression model using state variables of the DCT that are related to a line pressure change, and driving the electric oil pump when the line pressure estimated based on the linear regression model reaches a predetermined lower limit.

A line pressure control method for a double clutch transmission (DCT) includes estimating a line pressure, which decreases with stoppage of an electric oil pump, based on a linear regression model using state variables of the DCT that are related to a line pressure change, and driving the electric oil pump when the line pressure estimated based on the linear regression model reaches a predetermined lower limit.

An output is calculated using, as an input, a measured value of a pump discharge pressure in a neural network having the pump discharge pressure as the input and a pump rotational speed as the output. A leakage degree of oil of the hydraulic circuit of a transmission is estimated based on a difference obtained by subtracting a measured value of the pump rotational speed from the calculated value of the output. Learning of the neural network is performed using, as teacher data, the measured values of the pump discharge pressure and the pump rotational speed in the transmission in which the leakage degree of oil is within an allowable range.

An output is calculated using, as an input, a measured value of a pump discharge pressure in a neural network having the pump discharge pressure as the input and a pump rotational speed as the output. A leakage degree of oil of the hydraulic circuit of a transmission is estimated based on a difference obtained by subtracting a measured value of the pump rotational speed from the calculated value of the output. Learning of the neural network is performed using, as teacher data, the measured values of the pump discharge pressure and the pump rotational speed in the transmission in which the leakage degree of oil is within an allowable range.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A controller controls the shift actuator utilizing an actuating pulse and an opposing pulse.