A vehicle includes: an internal combustion engine; a rotary electric machine; a connection-disconnection device; a hydraulic pressure supply device; a hydraulic pressure control device; and a control device. The hydraulic pressure supply device includes a mechanical hydraulic pressure supply device and a pressure accumulator. The control device executes fuel cut-off control to stop fuel supply to the internal combustion engine and rotation speed maintaining control to maintain a rotation speed of the internal combustion engine at a predetermined rotation speed by rotationally driving the internal combustion engine by the rotary electric machine or supplying fuel to the internal combustion engine. The hydraulic pressure control device supplies the hydraulic pressure to the connection-disconnection device by the pressure accumulator when the hydraulic pressure supplied to the connection-disconnection device by the mechanical hydraulic pressure supply device is less than a predetermined value when an acceleration command is given to the vehicle.

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 hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A hydraulic system for an automatic transmission of a motor vehicle, including a high pressure circuit in which a pressure accumulator, at least one clutch and a gear selector are connected, and comprising a low pressure circuit for cooling the clutch, wherein the high pressure circuit and the low pressure circuit have at least one hydraulic pump that can be driven by an electric motor, and including a control unit that actuates the electric motor of the hydraulic pump when a pressure accumulator charging requirement is detected, wherein the high and low pressure circuits are connected via a bypass line to an integrated accumulator charging valve.

A work vehicle includes an engine, a speed changing apparatus that includes a hydrostatic stepless speed changing mechanism and is configured to subject motive power transmitted from the engine to speed changing and output the motive power, a travelling apparatus configured to travel on the motive power received from the speed changing apparatus, a speed detector configured to detect a speed of the travelling apparatus, a pressure detector configured to detect a hydraulic pressure in a closed circuit of the hydrostatic stepless speed changing mechanism, and a controller.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A hydraulic system (1) for electro-hydraulically pressing and/or moving a first (8) and a second (9) set of disks of a CVT transmission (10) is provided. The hydraulic system (1) includes two electrically driven hydraulic pumps (4, 5). In order to reduce energy consumption during operation of the hydraulic system, the hydraulic pumps (4, 5) are in the form of self-inhibiting hydraulic pumps (4, 5) which, when a hydraulic pressure is applied and the associated electric drive is switched off, substantially maintain the applied hydraulic pressure as a result of a static friction and a residual moment of the associated electric drive.

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.

Systems, methods, and apparatuses for operating a machine using energy stored in a compressed 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 the transmission. The gas may be compressed by a first fluid using a second fluid, and the two fluids are be prevented from being mixed together.

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.