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 system for controlling hydraulic fluid flow within a work vehicle includes a load sense valve configured to adjust the pressure of a bleed flow within a load sense conduit. Moreover, the system includes a computing system configured to determine the pressure of the hydraulic fluid within the fluid supply conduit downstream of the flow control valve based on the data captured by a pressure sensor. Furthermore, the computing device is configured to control an operation of the load sense valve to selectively adjust the pressure of the bleed flow within the load sense conduit based on the determined pressure.

A hydraulic system controller is disclosed. The hydraulic system controller may determine a maximum active circuit pressure of a set of active hydraulic circuits of the hydraulic system, wherein the hydraulic system includes a hydraulic pump to cause fluid to flow throughout the set of active hydraulic circuits; determine a circuit pressure of a hydraulic circuit of the hydraulic system; determine, based on a hydraulic flow command for the hydraulic circuit and the circuit pressure, a desired circuit delta-pressure for the hydraulic circuit; determine, based on the desired circuit delta-pressure and a pressure difference between the maximum active circuit pressure and the circuit pressure, a circuit valve setting for a circuit valve of the hydraulic circuit; and cause a control device to set a position of the circuit valve according to the circuit valve setting.

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 includes: hydraulic actuators; a control valve for controlling the hydraulic actuators; a tank for storing a hydraulic operation fluid; a variable displacement pump for supplying the hydraulic operation fluid to the hydraulic actuators; a regulator for controlling the variable displacement pump; a pilot pump for discharging a hydraulic pilot fluid; a load sensing system for maintaining a differential pressure to be a constant pressure, the differential pressure being obtained by subtracting a second signal pressure from a first signal pressure that is the discharge pressure of the variable displacement pump, the second signal pressure being the maximum one of the load pressures generated in the hydraulic actuators; a signal tube for sending the second signal pressure to the regulator; a throttle provided on the signal tube; and a warm-up circuit for supplying the hydraulic pilot fluid to a downstream side of the throttle.

The present disclosure relates to a hydraulic control circuit for crane slewing gear having directional valves arranged in work lines and controllable separately for the inflow and outflow to the hydraulic motor for the carrying out of a rotational movement of the slewing gear, wherein an inflow valve serves the control of the oil inflow from a hydraulic pump via the work line to the hydraulic motor and an outflow valve is provided via which the hydraulic motor can be relieved to the tank, wherein the work lines are each connected via at least one check valve to a common inlet of the outflow valve to relieve the hydraulic motor independently of the direction of rotation of the slewing gear via an outflow valve into the 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.

A hydraulic system in a work machine includes a travel operation device provided in a pilot oil path between a hydraulic pump a travel pump and including an operation member and configured to generate a pilot pressure supplied via the pilot oil path and an additional pilot pressure in accordance with an operation amount of the operation member. The travel pump is to control a flow direction of hydraulic oil supplied to a travel motor based on the pilot pressure and the additional pilot pressure. A pressure selection valve is provided in a first coupling oil path to select a selected pressure from the pilot pressure and the additional pilot pressure to apply the selected pressure to the pilot hydraulic oil in the second coupling oil path. A pressure adjustment valve is provided in a second coupling oil path to control the selected pressure to be an adjusted pilot pressure.

A system for controlling hydraulic fluid flow within a work vehicle includes a pilot conduit fluidly configured to receive a pilot flow of the hydraulic fluid from a fluid supply conduit such that an operation of a compensator valve is controlled based on a pressure of the pilot flow. Furthermore, the system includes a pilot conduit valve configured to adjust the pressure of the pilot flow within the pilot conduit. A computing system is configured to determine the pressure of the hydraulic fluid within the fluid supply conduit downstream of the flow control valve based on the data captured by a pressure sensor. Furthermore, the computing system is configured to control an operation of the pilot conduit valve to selectively adjust the pressure of the pilot flow within the pilot conduit based on the determined pressure.

A system for controlling hydraulic fluid flow within a work vehicle includes a load sense valve configured to adjust the pressure of a bleed flow within a load sense conduit. Moreover, the system includes a computing system configured to determine the pressure of the hydraulic fluid within the fluid supply conduit downstream of the flow control valve based on the data captured by a pressure sensor. Furthermore, the computing device is configured to control an operation of the load sense valve to selectively adjust the pressure of the bleed flow within the load sense conduit based on the determined pressure.