A self-contained pressure compensation system and a control method thereof are provided, wherein the self-contained pressure compensation system comprises an oil supply device, a pressure compensation device, a power unit associated with the pressure compensation device, and a switch control device, the pressure compensation device supplies oil to the power unit and detects a change in a chamber pressure of itself in real time, the switch control device triggers the oil supply device to supply oil to the pressure compensation device if the chamber pressure is less than a predetermined first threshold and triggers the oil supply device to stop supplying oil to the pressure compensation device if the chamber pressure is greater than a predetermined second threshold. The invention can detect a chamber pressure of the pressure compensation device in real-time and can achieve automatic oil refilling, and can provide pressure compensation for the power unit effectively.

A hydraulic system includes a first electric machine connected to a first hydraulic machine and a second electric machine connected to a second hydraulic machine. An output side of the second hydraulic machine is connected to an input side of the first hydraulic machine. A hydraulic consumer is hydraulically coupled to an output side of the first hydraulic machine via a supply line and is powered by the first hydraulic machine. A return line hydraulically couples the hydraulic consumer to an input side of the first hydraulic machine. The second hydraulic machine provides a flow of hydraulic fluid to the input side of the first hydraulic machine if a requested flow from the first hydraulic machine exceeds a flow of the return line and recuperates energy if the requested flow from the first hydraulic machine is lower than the flow of the return line.

A header assembly for an agricultural harvesting machine comprises a first frame assembly, a second frame assembly that supports a cutter, and is movable relative to the first frame assembly, a float cylinder coupled between the first frame assembly and the second frame assembly, an accumulator, a controllable reservoir, and fluidic circuitry. The fluidic circuitry comprises a first conduit forming a first fluid path that provides a flow of pressurized fluid under pressure to the float cylinder, so the float cylinder exerts a float force on the second frame assembly, a valve mechanism that is actuatable to inhibit fluid flow along the first fluid path between the accumulator and the float cylinder, a second conduit forming a second fluid path fluidically coupled to the controllable reservoir, the controllable reservoir being controllable to add fluid to the float cylinder.

An energy recuperation system for construction equipment includes an actuator driving upward and downward operations of a work unit; an accumulator connected to the actuator; and a controller determining a predicted downward mode associated with the downward operation of the work unit, regulating a dischargeable lowest limit pressure of the accumulator to a target pressure corresponding to the predicted downward mode, and charging the accumulator having the dischargeable lowest limit pressure regulated to the target pressure with pressurized oil discharged from the actuator during the downward operation of the work unit to recuperate energy, and an energy recuperation method.

The invention relates to a hydraulic device for a hydraulic system (12). The hydraulic device includes a chamber arrangement including at least one high-pressure chamber for connection to a high-pressure side of the hydraulic system, and at least one low-pressure chamber for connection to a low-pressure side of the hydraulic system; and a movable member arranged to reciprocate at least partly inside the chamber arrangement in response to pressure variations within the at least one high-pressure chamber and within the at least one low-pressure chamber. The chamber arrangement further includes at least one tank chamber for connection to a tank-pressure side of the hydraulic system.

An accumulator assembly for providing hydraulic fluid to an actuator. That assembly includes an accumulator for containing a supply of hydraulic fluid, the accumulator having an exit port via which hydraulic fluid can flow, in use, to the actuator. The assembly also includes a coupling comprising a first coupling part configured to be located at an inlet port of the actuator and a second coupling part arranged at the exit port of the accumulator. The first and second coupling parts are configured to matingly engage to form an open passage for flow of the fluid-between the accumulator and the actuator, and to close the first coupling part when the first second coupling parts are not engaged, so as to prevent flow from the actuator and to prevent air and pollution ingress the actuator.

A hydraulic system includes: a high-pressure line; a pump configured to supply pressurized hydraulic fluid to the high-pressure line; a variable displacement hydraulic machine connected by a fluid connection to the high-pressure line for rotationally driving the rotatable load; an electronic control unit; an energy storing device connected to the high-pressure line and configured to communicate with the high-pressure line by receiving energy from the high-pressure line and/or supplying energy to the high-pressure line; and a first detector configured to detect the amount of energy stored in the energy storing device and to transmit a signal indicating said amount of energy stored to the electronic control unit. The electronic control unit is configured to control the volume flow intake of the variable displacement hydraulic machine dependent on a target output of the variable displacement hydraulic machine and on the detected amount of energy stored in the energy storing device.

A hydraulic system for a work vehicle has a first hydraulic circuit at a first nominal pressure and a second hydraulic circuit at a second nominal pressure different than the first nominal pressure. A dual-chamber hydraulic reservoir includes a first tank associated with the first hydraulic circuit and defining a first opening and a second tank associated with the second hydraulic circuit and defining a second opening. An exchange system has a particulate filter disposed within an exchange path between the first opening of the first tank and the second opening of the second tank. The exchange system is configured to resupply the first tank with hydraulic fluid from the second tank.

A control device for an agricultural application device which has an application boom pivotally mounted on a carrier, on which application components are arranged for applying liquid and/or solid active substances. The control device has a pressure supply connection and a return connection and a controllable valve arrangement and a hydraulic cylinder arrangement, which has a first cylinder effective area, connected to the valve arrangement and a second cylinder effective area, wherein the two cylinder effective areas can be pressurized and each are connected to a hydraulic accumulator, and wherein the pivot position of the application boom is variable by changing the switching state of the valve arrangement. In order to further develop the control device in such a way that the spring rate of the application boom can be decoupled from its pivot position, it is proposed according to the invention that the cylinder effective areas can be pressurized with a predeterminable pressure independent of the pivot position of the application boom. In addition, an agricultural application device having such a control device is proposed.

The present disclosure relates to a hydraulic circuit, comprising: a hydraulic displacement unit for driving an implement; a hydraulic machine fluidly connected or selectively fluidly connected with the hydraulic displacement unit the hydraulic machine having a fixed hydraulic displacement; an electric machine drivingly engaged or selectively drivingly engaged with the hydraulic machine; a hydraulic pump fluidly connected or selectively fluidly connected with the hydraulic displacement unit, the hydraulic pump having a variable hydraulic displacement; and an electric motor drivingly engaged or selectively drivingly engaged with the hydraulic pump.