A hydraulic control arrangement for simultaneously supplying at least two hydraulic consumers with predefinable individual pressure medium flow rates includes a hydraulic pump having an adjustable swept volume, and at least two valve arrangements each including a variable metering restrictor and a pressure balance arranged downstream of the variable metering restrictor. Each pressure balance is configured to be acted on in an opening direction by pressure downstream of the respective variable metering restrictor and to be acted on in a closing direction by a highest load pressure or by a pressure derived therefrom. Each valve arrangement is arranged between a pump line, which leads away from the hydraulic pump, and a consumer of the at least two hydraulic consumers. The arrangement further includes an electronic control device, by which the hydraulic pump is actuatable such that it conveys a sum of the predefinable individual pressure medium flow rates.

The present disclosure relates to an apparatus for controlling/regulating the travel speed of a utility vehicle comprising at least one drive motor, at least one hydraulic pump, at least one control slide valve, at least one hydraulic travel motor, at least one further hydraulic drive, as well as at least one controller. In accordance with the present disclosure, the travel speed of the at least one hydraulic travel motor is controlled/regulated via at least the speed of the drive motor, while the at least one further hydraulic drive does not provide any drive power.

A hydraulic system is provided. The hydraulic system includes a pump, a load sense conduit, a tank conduit, a function workport, and a function control valve. The hydraulic system further includes a function poppet valve arranged between the function workport and the function control valve and having a function poppet vent passage, and a system control valve arranged downstream of the function control valve. The system control valve is biased into a first position where fluid communication between the function poppet vent passage and the tank conduit is prevented and fluid communication between the load sense conduit and the tank conduit is provided. The system control valve is selectively movable to a second position where fluid communication between the function poppet vent passage and the tank conduit is allowed and fluid communication between the load sense conduit and the tank conduit is prevented.

Hydraulic pressure compensator units and hydraulic systems incorporating hydraulic pressure compensator units. The pressure compensator units include a main valve body defining a central axis and a first central passage, a compensation valve member positioned in the first central passage and defining a second central passage, the first central passage being in selective fluid communication with a port of hydraulic actuator. A load sense check component is positioned within the second central passage and adapted to move in a first axial direction to selectively open a fluid communication between a pump output and a load sense line. A reverse flow check component is positioned within the second central passage and adapted to move in a second axial direction opposite the first axial direction to selectively open a fluid communication between the hydraulic actuator and a tank line.

A hydraulic system includes first and second valve assemblies connected to a common pump. The first valve assembly includes a main valve housed inside a manifold. A pressure compensator valve maintains a constant pressure drop across a variable orifice of the main valve. A pressure limiter valve is in communication with the main valve and the pressure compensator valve, and allows an actuator connected to the first valve assembly to operate independently of the second valve assembly so that fluid flow to a work port of the first valve assembly is not interrupted by operation of the second valve assembly.

The present disclosure relates to the technical field of cranes, and in particular to a crane hydraulic control system and a crane. The crane hydraulic control system of the present disclosure includes a prime mover, an execution control mechanism, a hydraulic baking device, a running energy recycling device and an operation energy recycling device. By means of cooperation among the operation energy recycling device, the energy recovery device and the hydraulic energy conversion device, kinetic energy in a driving braking process of the crane and the potential energy in a load lowering process are respectively converted into hydraulic energy for recovery, storage and reuse, therefore, the present disclosure can achieve the recovery of the superstructure energy and the lower vehicle energy of the crane so as to effectively reduce the energy waste.

A hydraulic system includes first and second valve assemblies connected to a common pump. The first valve assembly includes a main valve housed inside a manifold. A pressure compensator valve maintains a constant pressure drop across a variable orifice of the main valve. A pressure limiter valve is in communication with the main valve and the pressure compensator valve, and allows an actuator connected to the first valve assembly to operate independently of the second valve assembly so that fluid flow to a work port of the first valve assembly is not interrupted by operation of the second valve assembly.

A hydraulic system is provided. The hydraulic system includes a pump, a load sense conduit, a tank conduit, a function workport, and a function control valve. The hydraulic system further includes a function poppet valve arranged between the function workport and the function control valve and having a function poppet vent passage, and a system control valve arranged downstream of the function control valve. The system control valve is biased into a first position where fluid communication between the function poppet vent passage and the tank conduit is prevented and fluid communication between the load sense conduit and the tank conduit is provided. The system control valve is selectively movable to a second position where fluid communication between the function poppet vent passage and the tank conduit is allowed and fluid communication between the load sense conduit and the tank conduit is prevented.

Hydraulic pressure compensator units and hydraulic systems incorporating hydraulic pressure compensator units. The pressure compensator units include a main valve body defining a central axis and a first central passage, a compensation valve member positioned in the first central passage and defining a second central passage, the first central passage being in selective fluid communication with a port of hydraulic actuator. A load sense check component is positioned within the second central passage and adapted to move in a first axial direction to selectively open a fluid communication between a pump output and a load sense line. A reverse flow check component is positioned within the second central passage and adapted to move in a second axial direction opposite the first axial direction to selectively open a fluid communication between the hydraulic actuator and a tank line.

A Control Valve Compensation System for producing both a pre-compensated and a post-compensated load sensing hydraulic directional control valve module, wherein both configurations use the same components except for a sliding compensating component. The Control Valve Compensation System generally includes a hydraulic directional control valve housing which is adapted to be easily-interchangeable between a load sensing pre-compensated pressure configuration and a load sensing post-compensated pressure configuration by simply removing and replacing a different compensator assembly within the housing. The compensator assembly is adapted to direct oil flow through the housing while simultaneously providing compensation for the valve function. Directional valve assemblies may be provided, with the valve assemblies functioning to provide post-compensated functions, pre-compensated functions, and mixed pre- and post-compensated functions. These directional valve functions can be re-configured in the field by simply swapping the compensator assemblies to produce the desired functionality of the end-user at that particular time.