A hydraulic system for a mobile work vehicle is configurable in a hybrid mode and a hydrostatic mode. The hydraulic system includes a pump/motor, a propel circuit, a pump, a hydraulic accumulator, and an accessory circuit. The pump/motor is adapted to exchange power with a drive train of the mobile work vehicle. The propel circuit is adapted to exchange hydraulic fluid power with the pump/motor. The pump is adapted to transfer power from a prime mover of the mobile work vehicle to the propel circuit. The hydraulic accumulator is adapted to exchange hydraulic fluid power via an accumulator isolation valve with the propel circuit when the hydraulic system is configured in the hybrid mode. The accessory circuit is adapted to receive hydraulic fluid power from the hydraulic accumulator, at least when the hydraulic system is configured in the hydrostatic mode and the accumulator isolation valve is closed.

A hydraulic system for a mobile work vehicle is configurable in a hybrid mode and a hydrostatic mode. The hydraulic system includes a pump/motor, a propel circuit, a pump, a hydraulic accumulator, and an accessory circuit. The pump/motor is adapted to exchange power with a drive train of the mobile work vehicle. The propel circuit is adapted to exchange hydraulic fluid power with the pump/motor. The pump is adapted to transfer power from a prime mover of the mobile work vehicle to the propel circuit. The hydraulic accumulator is adapted to exchange hydraulic fluid power via an accumulator isolation valve with the propel circuit when the hydraulic system is configured in the hybrid mode. The accessory circuit is adapted to receive hydraulic fluid power from the hydraulic accumulator, at least when the hydraulic system is configured in the hydrostatic mode and the accumulator isolation valve is closed.

A power train and related vehicle are described for multi-mode power transmission. A first continuously variable power source (“CVP”) may convert rotational power received by the engine for transmission to a second CVP. A variator assembly may receive rotational power from the second CVP at a first input and directly from the engine at a second input. A control assembly may include one or more output components and a plurality of clutch devices arranged between the one or more output components and the variator assembly and engine. In a first state of the control assembly, the plurality of clutch devices may collectively provide direct power transmission between the engine and the one or more output components. In a second state of the control assembly, the plurality of clutches may collectively provide power transmission between the variator and the one or more output components.

An integrated hybrid energy recovery and storage system for recovering and storing energy from multiple energy sources is disclosed. The system includes an accumulator unit having a high pressure accumulator and a low pressure accumulator. At least one piston is mounted for reciprocation in the high pressure accumulator. The accumulator unit is configured to receive, store, and transfer energy from the hydraulic fluid to the energy storage media. The system further includes two or more rotational directional control valves, in which at least one rotational directional control valve is positioned on each side of the accumulator unit. Each rotational directional control valve includes multiple ports. The system also includes two or more variable displacement hydraulic rotational units. At least one variable displacement hydraulic rotational unit is positioned adjacent each of the rotational directional control valves.

In a power control device, when the necessary power is greater than an upper limit value and either the integral power value or the duration time of an assist provided by an electric storage device during a continuous assist by the electric storage device exceeds a predetermined first threshold value, a controller performs a first control of reducing an assist power by the electric storage device to a value smaller than an assist power for the regular control and greater than zero. Further, when the necessary power is greater than the upper limit value and either the integral power value or the duration time exceeds a predetermined second threshold value greater than the first threshold value, the controller performs a second control of setting the assist power to zero.

A series hydraulic hybrid system for a vehicle may have: a hydraulic circuit with a first hydraulic displacement unit in fluid communication with a second hydraulic displacement unit, a hydraulic actuator, and a hydraulic accumulator assembly. The hydraulic accumulator assembly is selectively in fluid communication with the hydraulic circuit via at least one controllable circuit valve. The hydraulic accumulator assembly is selectively in fluid communication with the hydraulic actuator via at least one controllable actuator valve, such that the hydraulic accumulator assembly is configured to be selectively fluidly connected with and to be selectively fluidly disconnected from the hydraulic actuator via the at least one actuator valve independently of a control position of the at least one circuit valve. A method of operating the system is also described.

A series hydraulic hybrid system for a vehicle may have: a hydraulic circuit with a first hydraulic displacement unit in fluid communication with a second hydraulic displacement unit, a hydraulic actuator, and a hydraulic accumulator assembly. The hydraulic accumulator assembly is selectively in fluid communication with the hydraulic circuit via at least one controllable circuit valve. The hydraulic accumulator assembly is selectively in fluid communication with the hydraulic actuator via at least one controllable actuator valve, such that the hydraulic accumulator assembly is configured to be selectively fluidly connected with and to be selectively fluidly disconnected from the hydraulic actuator via the at least one actuator valve independently of a control position of the at least one circuit valve. A method of operating the system is also described.

An energy storage and regeneration system that converts irregular, non-constant, and variable input power to regular, constant, and controlled output power using hydraulics whereby the irregular input power is used to pump hydraulic fluid into an accumulator array where it is stored pressurized. Energy is released in a controlled fashion using a hydraulic motor operated by the pressurized hydraulic fluid from the accumulator array, in accordance with the specified power demand. One or more power units may be deployed depending on the amount of energy required at the output. Each power unit includes a hydraulic motor and associated floating accumulator whose internal pressure is controlled to maintain a substantially constant pressure differential across its associated motor. The system can be integrated into various energy system sources including renewable energy such as wind, PV or thermal solar, wave, tidal, etc. as well as various types of vehicles such as cars, trucks, motorcycles, trains, boats, etc.

An energy storage and regeneration system that converts irregular, non-constant, and variable input power to regular, constant, and controlled output power using hydraulics whereby the irregular input power is used to pump hydraulic fluid into an accumulator array where it is stored pressurized. Energy is released in a controlled fashion using a hydraulic motor operated by the pressurized hydraulic fluid from the accumulator array, in accordance with the specified power demand. One or more power units may be deployed depending on the amount of energy required at the output. Each power unit includes a hydraulic motor and associated floating accumulator whose internal pressure is controlled to maintain a substantially constant pressure differential across its associated motor. The system can be integrated into various energy system sources including renewable energy such as wind, PV or thermal solar, wave, tidal, etc. as well as various types of vehicles such as cars, trucks, motorcycles, trains, boats, etc.

A number of variations include a product comprising a transfer case comprising a hydraulic system comprising a hydraulic fluid and a hydraulic pump or hydraulic motor wherein the hydraulic system is constructed and arranged to capture energy from regenerative braking of the at least one brake of at least one drive.