A number of variations may include a fluid accumulator comprising, a housing and at least one movable piston wherein the piston separates an interior of the housing into a first chamber constructed and arranged for containing a first fluid, and a second chamber constructed and arranged for containing a second fluid, and wherein the first chamber has an first fluid opening and a first fluid exhaust constructed and arranged to expel excess first fluid from the fluid accumulator and prevent first fluid from entering the second chamber.

Methods and systems for improving operation of a vehicle driveline that includes an engine and an automatic transmission with a torque converter are presented. In one non-limiting example, the engine may be stopped while a vehicle in which the engine operates is rolling. A transmission coupled to the engine may be shifted as the vehicle rolls so that vehicle response may be improved if a driver requests an increase of engine torque.

A hydraulic transformer clutch enables controlled power transfer from an outer race to an output shaft. The outer race is driven by a rolling element and generates spin against its own axis. The rolling element is in contact with a rotating lever, which can rotate against a pin. A boss keeps the rolling element in contact with the rotating lever. The rotating lever is actuated by a piston via a contact surface. During the actuation process, the rotating lever wedges the rolling element, creating a rigid connection between the outer race and the output shaft. This connection, and resulting engagement of the outer race and the output shaft, is maintained as long as the piston is actuated.

A hydraulic assembly for a vehicle transmission includes a hydraulic pump for providing a system pressure within a hydraulic circuit, a pressure accumulator for temporarily supplying pressure to the hydraulic circuit, and a valve assembly for charging the pressure accumulator after a predetermined pressure threshold value of the system pressure has been reached or exceeded. The valve assembly is hydraulically connected between the pump and the pressure accumulator.

A hydraulic assembly for a vehicle transmission includes a hydraulic pump for providing a system pressure within a hydraulic circuit, a pressure accumulator for temporarily supplying pressure to the hydraulic circuit, and a valve assembly for charging the pressure accumulator after a predetermined pressure threshold value of the system pressure has been reached or exceeded. The valve assembly is hydraulically connected between the pump and the pressure accumulator.

A hydraulic system for a vehicle transmission with at least two friction elements, the system comprising a first hydraulic circuit comprising a pump for supplying hydraulic fluid to the first hydraulic circuit. A flow restriction may be provided in the first hydraulic circuit between an output of the pump and a sump for providing leakage of hydraulic fluid into the sump. Further, a second hydraulic circuit comprising a second pump may be arranged, wherein the hydraulic pressure in the first circuit is higher compared to the second circuit. A flow control element operated using hydraulic pressure from the first circuit may be arranged for controlling flow/pressure in the second circuit. Further, the hydraulic system may be arranged for generating a line pressure, wherein an actuator for engaging a park lock system may be connected to the first hydraulic circuit for enabling direct actuation by means of the line pressure.

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.

Systems, methods, and apparatuses for operating a machine using energy stored in a compress gas are disclosed. Energy stored in the compressed gas may be used to pressurize a fluid, such as transmission fluid, and the pressurized fluid may be used to effectuate an operation of the machine, such as a transmission, and the operation of the machine may involve shifting of a transmission. The gas may be compressed with another fluid that is different from the fluid used to operate the machine, and the two fluid may be prevented from being mixed together.

A fastening bolt fixes a plurality of stacked plates on each of which a hydraulic integrated circuit for hydraulically controlling an automatic transmission or a continuously variable transmission is formed. The fastening bolt includes a communication passage that communicates between the hydraulic integrated circuits among the plurality of plates.

A transmission system includes a transmission assembly having clutches to transmit power from an input shaft to an output shaft at a plurality of gear ratios. A traction motor drives the input shaft and propels the work vehicle, while a controller controls operation of the transmission assembly and the traction motor. A hydraulic circuit controls actuation of the clutches responsive to commands from the controller. The hydraulic circuit includes a hydraulic pump driven by the traction motor, an accumulator connected to the hydraulic pump and that holds hydraulic fluid therein under pressure, and an unloading valve positioned in a secondary fluid path running from an outlet of the hydraulic pump to a sump. The unloading valve operates in a closed state to direct hydraulic fluid from the hydraulic pump to the accumulator and operates in an open state to direct hydraulic fluid from the hydraulic pump to the sump.