Various vehicle systems capable of different operation modes are disclosed. According to one example, the system can include at least one input shaft, at least one output shaft, a plurality of hydraulic devices, and one or more accessories. The plurality of hydraulic devices can be configured to be operable as vane pumps in a retracted vane mode of operation and can be configured to be operable as a hydraulic couplings to couple the at least one input shaft with the at least one output shaft in a vane extended mode of operation. The plurality of hydraulic devices can be simultaneously operable as the hydraulic couplings and the vane pumps. The one or more accessories can be in fluid communication with the plurality of hydraulic devices and can be configured to receive a hydraulic fluid pumped from one or more the plurality of hydraulic devices when operating as the vane pumps.

A vehicle drive assistance system equipped with an open hydraulic circuit has a hydraulic pump, a hydraulic motor and a reservoir. The system has a three-position valve suitable for: in a first position, supplying the hydraulic motor in a first direction of operation; in a second position, fluidly isolating the hydraulic motor from the hydraulic pump and connecting the hydraulic motor to the reservoir; and in a third position, supplying the hydraulic motor in a second direction of operation. A flow controller is positioned between the hydraulic pump and the three-position valve. The flow controller is configured in such a way as to selectively allow or not allow the passage of fluid through the supply duct of the hydraulic pump toward the three-position valve.

A vehicle drive assistance system equipped with an open hydraulic circuit has a hydraulic pump, a hydraulic motor and a reservoir. The system has a three-position valve suitable for: in a first position, supplying the hydraulic motor in a first direction of operation; in a second position, fluidly isolating the hydraulic motor from the hydraulic pump and connecting the hydraulic motor to the reservoir; and in a third position, supplying the hydraulic motor in a second direction of operation. A flow controller is positioned between the hydraulic pump and the three-position valve. The flow controller is configured in such a way as to selectively allow or not allow the passage of fluid through the supply duct of the hydraulic pump toward the three-position valve.

A vehicle drive system, comprises a battery, a power unit in a housing, which itself comprises at least one electric motor/generator, capable of being driven as a motor by the battery or of charging the battery as a generator, at least one hydraulic motor/pump, capable of being driven by the electric motor/generator to pressurize hydraulic fluid, or of being driven by pressurized hydraulic fluid to power the motor generator as a generator, a hydraulic rail communicating the pump, a directional control valves communicating with the hydraulic rail, at least one accumulator for storing pressurized hydraulic fluid, wheel drives capable of being driven by pressurized hydraulic fluid, a hydraulic circuit connecting the directional control valves of the motor housing to the accumulator and wheel drives, and a control system for controlling the operation of the battery, power unit and wheel drives.

When an inclination angle is greater than or equal to a first threshold, a controller determines a displacement of a hydraulic pump from a command vehicle speed based on second pump data and determines a displacement of a hydraulic motor from the command vehicle speed based on second motor data. The second pump data defines the displacement of the hydraulic pump that is smaller than that of first pump data with respect to the command vehicle speed. The second motor data defines the displacement of the hydraulic motor that is smaller than that of first motor data with respect to the command vehicle speed.

A sea wave power plant for generating electricity, and for supplying high pressure fluids to a water purification system. The power plant includes two compartments adjustable differential hydro cylinders that are assembled on floaters, an axial piston variable motor, a system for protecting the floaters in periods of storm in a way that the floater are positioned horizontally outside the water, and an automation sub-system. The wave power plant is combined of several modular units that each one of them serves as independent sea water power plan.

A renewable energy and waste heat harvesting system 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 collects energy from a renewable energy source and transfers the collected energy using the pressurized hydraulic fluid. The system further includes one 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 one 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.

A hydraulic system of a work machine includes a first hydraulic device to operate in a first operation mode while pressure of hydraulic oil supplied from a hydraulic pump via a first oil passage is equal to or higher than a first pressure threshold. The hydraulic oil in the first oil passage is to be discharged via a second oil passage. A pilot check valve is provided in the second oil passage and has a pilot port to receive a pilot pressure of the hydraulic oil. The pilot check valve is closed to stop discharging the hydraulic oil in the first oil passage through the second oil passage while the pilot pressure is lower than the fourth pressure threshold. The pilot check valve is opened while the pilot pressure is higher than or equal to the fourth pressure threshold. The first hydraulic device is a ride control device.

A hydraulic system of a work machine includes a first hydraulic device to operate in a first operation mode while pressure of hydraulic oil supplied from a hydraulic pump via a first oil passage is equal to or higher than a first pressure threshold. The hydraulic oil in the first oil passage is to be discharged via a second oil passage. A pilot check valve is provided in the second oil passage and has a pilot port to receive a pilot pressure of the hydraulic oil. The pilot check valve is closed to stop discharging the hydraulic oil in the first oil passage through the second oil passage while the pilot pressure is lower than the fourth pressure threshold. The pilot check valve is opened while the pilot pressure is higher than or equal to the fourth pressure threshold. The first hydraulic device is a ride control device.

An automobile or other wheeled vehicle includes various hydraulic components, including a hydraulic gearbox, transmission, clutch, and brake energy recovery system. Such hydraulic components supplement or replace traditional mechanical components of the automobile or other wheeled vehicle to improve the overall operational efficiency thereof.