A load sense pressure regulating system is provided. The load sense pressure regulating system can be operable between a flow regulation mode and a pressure limiting mode. When the load sense pressure control system is in the flow regulation mode, flow between a load sense inlet and a pilot vent are metered by a main poppet. The load sense pressure regulating system can also include a control valve downstream from the pilot vent that is configured to control a relief setting of a relief valve to regulate the load sense pressure within a desired operating range.

A control arrangement for an arrangement of hydraulically couplable machines has an interface for hydraulic coupling of the machines, and a hydraulic machine for supplying pressure medium to at least one hydraulic consumer of the machines in accordance with requirements. An electronic control device is configured, in accordance with a load of the consumer, to generate an electronic control signal, which can be converted by a transducer of the control arrangement into a hydraulic control signal, in accordance with which the hydraulic machine can be operated.

A hydraulic system for controlling an implement on a work machine may include a hydraulic reservoir, a hydraulic pump in fluid communication with the reservoir, a central valve in fluid communication with the pump and configured for controlling the implement, a pressure relief system arranged in fluid communication with the hydraulic pump and the central valve, and a controller. The controller may be configured for controlling the hydraulic pump, the central valve and the pressure relief system and selecting between operating the hydraulic system at a first pressure and a second pressure based on a factor relating to implement position.

A hydraulic system for a machine includes an implement pump, a valve, and an implement valve subsystem. The implement pump includes a load sensing control, and the valve controls the flow of hydraulic fluid to the implement pump. The implement valve subsystem includes one or more implement control subsystems to control movement of an implement. The valve is an electrohydraulic proportional relief valve and includes a solenoid configured to adjust the pressure of hydraulic fluid delivered to the implement pump proportionally to a current delivered through the solenoid.

A pressure compensated load sense hydraulic system and method is disclosed where a first pressure compensated valve controls flow between a pump and a first function based on a highest function load; and a second pressure compensated valve controls flow between the pump and a second function based on the highest function load. First and second operator controls activate the first and second functions, respectively. When the first function is stalled and the second function is activated, the controller closes the first valve to remove the first function load from the load sense circuit and prevent flow to or from the first function. The controller can determine the first function is stalled when a timer exceeds an initialization period. When the controller closes the first valve, it can cycle the first valve between a shutoff period where the valve is closed, and a refresh period where the valve is opened.

A hydraulic system for controlling an implement on a work machine may include a hydraulic reservoir, a hydraulic pump in fluid communication with the reservoir, a central valve in fluid communication with the pump and configured for controlling the implement, a load sense pressure relief system, and a controller. The controller may be configured for controlling the central valve and the load sense pressure relief system and selecting between operating the hydraulic system at a first pressure and a second pressure based on a factor relating to implement position.

A system for controlling hydraulic fluid flow within a work vehicle includes a flow control valve fluidly coupled to a fluid supply conduit upstream of a hydraulic actuator such that the flow control valve is configured to control the flow rate of hydraulic fluid to the hydraulic actuator. Furthermore, the system includes a computing system configured to receive an input associated with a selected flow rate of the hydraulic fluid being supplied to the hydraulic actuator. Moreover, the computing system is configured to control an operation of the flow control valve such that flow control valve is at a maximum flow position at which an adjustable orifice defined by the valve has a maximum cross-sectional area. Additionally, the computing system is configured to control an operation of a pump such that the pump supplies the hydraulic fluid to the hydraulic actuator through the adjustable orifice at the selected flow rate.

A three-way valve assembly, including a valve body having a fluid flow path and a valve member movable in the fluid flow path between a supply port and a work port, and between a load sense passage and a pressure relief port. The valve member may move between a first position and a second position for controlling flow and regulating fluid pressure differences sensed in the flow path; and for limiting fluid pressure in the flow path to a predetermined pressure level set by a pilot-operated pressure limiter valve when the valve member is in the second position. The valve member may move between the second position and a third position to open the flow path from the load sense passage to the pressure relief port for relieving fluid pressure in the flow path when the fluid pressure from an over-loaded actuator exceeds the predetermined pressure level set by the pressure limiter valve.

A hydrostatic drive includes a diesel engine and a hydrostatic adjustable machine which supplies multiple consumers in normal operation as a pump. The machine has a pressure/flow regulator to which is communicated, according to the load-sensing principle, the highest load pressure of the consumers, in particular when the machine is operated as a pump. In order to realize a start/stop function of the diesel engine, a previously charged high-pressure reservoir supplies the hydrostatic machine, which then acts as a starter motor for the diesel engine. In order to switch from pump to starter motor, the hydro-machine is adjusted over zero. In order for this switch to take place quickly and reliably, the pressure/flow regulator is deactivated by means of a switching valve and the adjustment device is supplied with an adjustment pressure medium via the switching valve, which medium is taken from the high-pressure reservoir or from an auxiliary reservoir.

A control device, for a hydraulic consumer (22) and susceptible to vibrations, includes a valve (24) having a control spool (40) controllable by an actuating device (46). The valve (24) has a pressure supply port (P), to which a pressure compensator valve can be connected, which can be supplied with pressure fluid from a pressure supply device. The actuating device (46) has a motor (74). A load-pressure-dependent force on the control spool (40) can be generated by a control device (66). That force at the control spool (40) acts on an electronic motor controller (208) of the DC motor (74), which detects a change of the force and acts as a damping of the vibrations of the consumer (22) against this change of force.