A power-split hydro-mechanical hybrid transmission system with an automatic adjustment function includes an input member, a hydraulic transmission mechanism, a split mechanism, a convergence mechanism, an output member, a clutch assembly, and a brake assembly. The clutch assembly connects the input member to an input end of the split mechanism, connects an output end of the split mechanism to an input end of the hydraulic transmission mechanism and an input end of the convergence mechanism, and connects an output end of the hydraulic transmission mechanism to the output member. An output end of the convergence mechanism is connected to the output member. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input member and the output member. The power-split hydro-mechanical hybrid transmission system enables multi-mode continuously variable transmission and has energy reuse and emergency support functions.

A hydraulic system for an automatic transmission of a motor vehicle, with which hydraulic cylinders of at least one clutch and of gear selectors can be actuated, which hydraulic system has a pressure accumulator for providing an accumulator pressure in the hydraulic system, wherein a clutch valve that can be actuated by the control unit is arranged in a clutch path leading from the pressure accumulator to the clutch hydraulic cylinder.

A hydraulic system for an automatic transmission of a motor vehicle, with which the hydraulic cylinders of at least one clutch and of gear selectors can be actuated, which hydraulic system has a pressure accumulator for providing an accumulator pressure in the hydraulic system. A gear selector valve that can be controlled by an electronic control unit is arranged in at least one gear selector path leading from the pressure accumulator to the gear selector hydraulic cylinder, with which valve the hydraulic pressure at the gear selector hydraulic cylinder can be adjusted, and a charging hydraulic pump which conveys hydraulic fluid into the hydraulic system in a charging process, in order to increase an accumulator pressure in the hydraulic system.

A hydraulic system for an automatic transmission of a motor vehicle, with which hydraulic cylinders of at least one clutch, and of gear selectors can be actuated, which hydraulic system includes a pressure accumulator for providing an accumulator pressure in the hydraulic system. In at least one clutch path leading from the pressure accumulator to the clutch hydraulic cylinder, a clutch valve, which can be operated by an electronic control unit, and with which a hydraulic pressure applied to the clutch hydraulic cylinder can be adjusted, and a pressure sensor, with which the hydraulic pressure applied to the clutch hydraulic cylinder can be detected, are arranged, and having a charging hydraulic pump, which delivers hydraulic fluid into the hydraulic system in a charging process to increase the actual accumulator pressure.

A hydraulic control unit comprising a central accumulator, a flow path connected to the accumulator, a reservoir sharing a fluid space with the accumulator, a pump, and a controllable valve. The flow path is integrally formed to comprise a first flow path and a second flow path. The pump is connected to the accumulator via the first flow path on a first side of the accumulator. The pump is further connected to the reservoir via an inlet flow path on the first side of the accumulator. The controllable valve is connected to the accumulator via the second flow path on a second side of the accumulator.

The invention relates to a method for controlling a hydraulic system of a vehicle driveline. According to the method a transmission (13) of a driveline (2) is controlled in a limited actuation mode, if the pressure (p) is below the predetermined critical lower threshold value (Tel), wherein in the limited actuation mode the transmission (13) is controlled such that less actuator actuations is performed in comparison to a normal actuation mode.

A hydraulic control unit comprises a housing, an accumulator, a gear pump assembly, and a motor. The housing comprises an accumulator compartment, a gear pump compartment, and a flow path section connecting the gear pump compartment and the accumulator compartment, the flow path section comprising at least a supply path and a pressurizing path. The accumulator in the accumulator compartment comprises a movable piston dividing the accumulator compartment into a high pressure reservoir and a low pressure reservoir. A gear pump assembly is in the gear pump compartment. The gear pump assembly is configured to draw return fluid from the low pressure reservoir via the supply path and to pump pressurized fluid through the pressurizing path to accumulate in the high pressure reservoir. A motor assembly is connected to the gear pump compartment of the housing and is configured to power the gear pump assembly.

A hydraulic control unit of a vehicle drive system including an automatic transmission, and an oil pump device, includes: a first electromagnetic valve; a second electromagnetic valve; first and second oil passages; a third oil passage; a manual valve operated to connect and disconnect the first and third oil passages and a drain oil passage to and from each other, in response to an operation of a manually operated shifting device by a vehicle operator, such that the first oil passage is connected to the third oil passage when the shifting device is placed in a first operating position, while the first oil passage is connected to the drain oil passage when the shifting device is placed in a second operating position; an accumulator connected to the first oil passage; and a check valve provided in the second oil passage.

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 hydraulic controlling system including: a cooling and lubricating oil line and a main controlling oil line; an oil-liquid storage; a first pump, wherein an inlet of the first pump is connected to the oil-liquid storage and an outlet of the first pump is connected to the main controlling oil line; a second pump, wherein an inlet of the second pump is connected to the oil-liquid storage and an outlet of the second pump selectively communicates with the cooling and lubricating oil line or the main controlling oil line; and a gearbox-gear-shifting oil line including a gear-shifting-pressure regulating valve, a plurality of gear-shifting-flow-rate controlling valves and a plurality of gear-shifting selector valves. The gear-shifting-flow-rate controlling valves are connected to the main controlling oil line via the gear-shifting-pressure regulating valve. At least some of the gear-shifting-flow-rate controlling valves are connected to a gear-shifting executing piston via the gear-shifting selector valves.