Methods and systems for a hydromechanical transmission are provided herein. In one example, a vehicle system is provided that includes a hydromechanical transmission with a power-take off (PTO) that is designed to rotationally couple to an implement. The vehicle system further includes an engine coupled to the hydromechanical transmission and a power-management control unit configured to, during a drive or coast condition, cause the power-management control unit to: determine a net available power for the hydromechanical transmission and manage a power flow between the hydromechanical transmission, a drive axle, and the implement based on the net available power.

During shift control of a transmission mechanism, a hybrid drive device computes the amount of change in input torque (deTr) acting on the transmission mechanism and an input torque change time (t15), and controls a motor so that motor torque is changed by the amount of change in input torque (deTr), when the motor can change the amount of change in input torque (deTr), and outputs, when the motor cannot change the amount of change in input torque (deTr), an engine torque signal (Tesig1) at an engine torque change time (t14) earlier than the input torque change time (t15) at which drive power of the motor is changed when the motor can change the amount of change in input torque (deTr).

During shift control of a transmission mechanism, a hybrid drive device computes the amount of change in input torque (deTr) acting on the transmission mechanism and an input torque change time (t15), and controls a motor so that motor torque is changed by the amount of change in input torque (deTr), when the motor can change the amount of change in input torque (deTr), and outputs, when the motor cannot change the amount of change in input torque (deTr), an engine torque signal (Tesig1) at an engine torque change time (t14) earlier than the input torque change time (t15) at which drive power of the motor is changed when the motor can change the amount of change in input torque (deTr).

A method for the traction-related control of a drive-train of a working machine (1) which has a drive unit (2), a transmission (3), a control unit (10) and first and second vehicle axles (7, 9) with rotatable wheels (6, 8). At least one of the vehicle axles (7, 9) is driven, and as a function of a specification either a first function (A) or a second function (B) is implemented. The first function (A) implements slip-orientated loading control and the second function (B) implements traction-efficiency control of the drive-train of the working machine (1).

An oil supply system of an automatic transmission or an automated manual transmission in a power train has an oil pan and a pressure line for supplying elements of the transmission with pressurized oil. A pumping device pumps oil from the oil pan into the pressure line at a supply pressure P.sub.0. A hydrodynamic converter, being a starting element, forms a subsection of the pressure line. A hydrodynamic retarder is disposed in a retarder oil circuit. At least a first switching valve, a second switching valve and a heat exchanger, wherein the heat exchanger is selectively switchable, by way of the switching valves, as a subsection into the pressure line or the retarder oil circuit. A temperature sensor is provided following the pumping device in the direction of flow in order to detect the oil temperature in the pressure line.

Methods and systems for a hydromechanical transmission. In one example, a vehicle system includes a hydromechanical transmission with a power-take off (PTO) that is designed to rotationally couple to an implement. The vehicle system further includes an engine coupled to the hydromechanical transmission and a power-management control unit configured to, during a drive or coast condition, cause the power-management control unit to: determine a net available power for the hydromechanical transmission and manage a power flow between the hydromechanical transmission, a drive axle, and the implement based on the net available power.

A method for reducing fuel consumption of a work vehicle may include monitoring one or more loads associated with both a drive power requirement and a hydraulic power requirement for the work vehicle. In addition, the method may include actively adjusting one or more operating parameters of the work vehicle based on the monitored loads in a manner that meets the drive power requirement and the hydraulic power requirement for the work vehicle while reducing the fuel consumption of the vehicle's engine.

An oil supply system of an automatic transmission or an automated manual transmission in a power train has an oil pan and a pressure line for supplying elements of the transmission with pressurized oil. A pumping device pumps oil from the oil pan into the pressure line at a supply pressure P.sub.0. A hydrodynamic converter, being a starting element, forms a subsection of the pressure line. A hydrodynamic retarder is disposed in a retarder oil circuit. At least a first switching valve, a second switching valve and a heat exchanger, wherein the heat exchanger is selectively switchable, by way of the switching valves, as a subsection into the pressure line or the retarder oil circuit. A temperature sensor is provided following the pumping device in the direction of flow in order to detect the oil temperature in the pressure line.

A method for reducing fuel consumption of a work vehicle may include monitoring one or more loads associated with both a drive power requirement and a hydraulic power requirement for the work vehicle. In addition, the method may include actively adjusting one or more operating parameters of the work vehicle based on the monitored loads in a manner that meets the drive power requirement and the hydraulic power requirement for the work vehicle while reducing the fuel consumption of the vehicle's engine.

A method of variably controlling a transmission pattern of a hybrid vehicle is provided. The method converts a transmission pattern into a pattern that sufficiently secures engine charge power by considering the total amount of electric load when the transmission pattern is determined based on a current SOC state. The method variably controls the transmission pattern of a hybrid vehicle to prevent a battery SOC excessive decrease due to an increase of electric load of a vehicle by reflecting and compensating for the used amount of electric load of a hybrid vehicle when the type of transmission pattern is determined. Also, fuel efficiency is improved based on the improvement of battery charge efficiency by determining the transmission pattern such that the speed of a transmission input terminal increases when the electric load increases and thus securing the engine charge power for the battery charge.