A method for operating a hydraulic consumer on an electrically actuated control valve includes providing the valve with an open valve position for establishing a connection between a valve inlet and a pilot line for influencing a pivot angle set on an axial piston pump and a system pressure which is present at the valve inlet and dependent on the pivot angle. Data regarding the current system pressure and the current pivot angle are detected and communicated to a control unit. The method includes determining an incorrect setting of the control valve if the control unit detects that a delivery volume flow of the axial piston pump is smaller than a value to be expected based on valve position, or the control unit detects that the system pressure present at the valve inlet is at a maximum without a delivery volume flow flowing in the direction of the hydraulic consumer.

A valve controller for a valve that comprises an actuator mechanically coupled to at least one flow controlling element. The valve controller comprises at least one pilot valve for controlling the position of the flow controlling element(s) by the actuator. The valve controller comprises a position sensor for obtaining a position signal indicative of the position of one of said at least one flow controlling element. The valve controller is configured to execute a configuration phase comprising establishing a pilot valve integer corresponding to number of pilot valves, and determining a tolerance criterion for the position signal based on the pilot valve integer. A valve arrangement comprising the valve controller and a valve. A method of controlling a valve comprising the configuration phase.

To make it possible to prevent a decrease in work speed due to a decrease in the speed of a given actuator when an operator unintentionally performs a fine operation of the control lever of the other actuator in a state in which the given actuator is driven by the hydraulic fluid delivered from a plurality of pumps, a controller (41) sets, as a composite dead zone line serving as a boundary of a composite dead zone, a composite dead zone line such that as an operation amount in one direction of a control lever (12L) or (13L) of a control lever device (12) or (13) is increased, the width of the composite dead zone corresponding to an operation amount in the other direction of the control lever is widened, and corrects the operation amount in the other direction such that the demanded flow rate of an actuator increases from zero, when the control lever is operated in the other direction in a state in which the operation amount in the one direction of the control lever remains within a range of the composite dead zone, and the operation amount in the other direction exceeds the composite dead zone line.

In one aspect, a system (110) for performing an action is disclosed. In one arrangement and embodiment, the system (110) comprises: a tool (118) operable to perform at least the action; a controller (122); storage (124) storing electronic program instructions for controlling the controller (122); and an input/output means (126). In one form, the controller (122) is operable, under control of the electronic program instructions, to: receive input via the input means; process the input, and on the basis of the processing, control the tool to perform the action. In one embodiment, the action comprises a hydraulic tuning action in respect of a system, such as a hydraulic pump (114), comprising a hydraulic circuit.

A method for ascertaining the movement of an armature of an electric intake valve, an electrical variable of the electric intake valve being controlled to predefined values with the aid of a two-position controller, a characteristic point in time of the movement of the armature being ascertained based on the switching behavior of the two-position controller.

Systems and methods for control of multi-function hydraulic commands of a multi-function electrohydraulic system are provided. In one aspect, a system for hydraulic control includes a first function in fluid communication with a first electrohydraulic control valve and a second function in fluid communication with a second electrohydraulic control valve. The system includes a controller in communication with the first electrohydraulic control valve and the second electrohydraulic control valve. The controller can be configured to receive an input target command, determine an achievable function rate based on the input target command, where the achievable function rate maintains a proportional relationship between the input target command and the achievable function rate. The controller can also map the achievable function rate to an output command based on a predetermined relationship between the achievable function rates and the output commands and supply the output command to the first and second electrohydraulic valves.

A construction machine that precisely enables derivation of the operation characteristics of hydraulic actuators in a high-velocity area with less calibration operation is provided. A controller (10) has a calibration mode in which the controller (10) derives operation characteristics (α(xs)) representing a relation among a spool position (xs) of a meter-in valve (8a1), an operation velocity (Va) of a hydraulic actuator (4a), and a differential pressure (ΔP) across the meter-in valve (8a1), and is configured to, in a case where the spool position (xs) of the meter-in valve (8a1) has changed in a direction to increase the opening area of the meter-in valve (8a1) in the calibration mode, output a command signal to increase the opening area of a bleed-off valve (8b1) to a bleed-off solenoid proportional pressure-reducing valve (8b2) as a command signal to reduce the differential pressure (ΔP).

Systems and methods for control of multi-function hydraulic commands of a multi -function electrohydraulic system are provided. In one aspect, a system for hydraulic control includes a first function in fluid communication with a first electrohydraulic control valve and a second function in fluid communication with a second electrohydraulic control valve. The system includes a controller in communication with the first electrohydraulic control valve and the second electrohydraulic control valve. The controller can be configured to receive an input target command, determine an achievable function rate based on the input target command, where the achievable function rate maintains a proportional relationship between the input target command and the achievable function rate. The controller can also map the achievable function rate to an output command based on a predetermined relationship between the achievable function rates and the output commands and supply the output command to the first and second electrohydraulic valves.

An open center hydraulic system (100) includes a tank configured to hold hydraulic fluid, a pump configured to provide pressurized hydraulic fluid from the tank, and a shunt valve configured to adapt a first opening area between a first input port and a first output port of the shunt valve dependent on a first control signal. The first input port is coupled to the pump, and the first output port is coupled to the tank. A first actuator valve is coupled to the first input port and configured to adapt a second opening area of the first actuator valve dependent on a second control signal. A hydraulic valve control unit is configured to determine a first opening area value and a second opening area value based on user input data and a predetermined relation dependent on the user input data, sending the first control signal, indicative of the first opening area value and sending the second control signal indicative of the second opening area value.

A calibration system is disclosed. The calibration system may include a sensor configured to measure a fluid level in a fluid tank of a machine, an actuator that, when actuated, affects a level of the machine, and a controller. The controller may be configured to: command actuation of the actuator at a current; receive, from the sensor and after commanding actuation of the actuator, information identifying the fluid level in the fluid tank; determine, based on the information identifying the fluid level in the fluid tank, whether there is a change to the fluid level in the fluid tank; and set an initiation current for the actuator at the current based on determining whether there is the change to the fluid level in the fluid tank.