The present invention provides a low-cost detachment determining device capable of determining whether or not an electromagnetic valve-equipped device has been detached. The detachment determining device determines whether or not at least a part of an electromagnetic valve-equipped device included in an industrial machine, such as a construction machine or an industrial vehicle, has been detached from the industrial machine, the electromagnetic valve-equipped device being a hydraulic device equipped with an electromagnetic valve. The detachment determining device includes: an electrical characteristic detecting portion configured to output a detection signal to the electromagnetic valve-equipped device and detect an electrical characteristic of the electromagnetic valve-equipped device based on the detection signal; and a detachment determining portion configured to determine, based on a plurality of electrical characteristics detected at different time points by the electrical characteristic detecting portion, whether or not at least a part of the electromagnetic valve-equipped device has been detached.

A valve block arrangement configured as a closed center system includes at least one main spool for controlling a hydraulic consumer. The main spool is configured to open and close at least one pressure medium connection between a hydraulic pump and the consumer in controlled, continuous fashion and, in at least one embodiment, is electrically activated. A bypass flow path with a cut valve branches off between the adjustable, hydraulic pump and the main spool. The cut valve is configured to open and close a pressure medium connection between the hydraulic pump and a tank in controlled, continuous fashion. The cut valve is electrically activatable.

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 variable displacement hydraulic pump or motor (10) includes: a swash plate (13); a lever (22) supported by a housing (21) and configured to rotate in conjunction of tilting of the swash plate (13); and a sensor (23) configured to detect a displacement amount of the lever (22).

The invention relates to a method for providing at least one piece of information about a hydraulic apparatus (1), wherein the following stages are performed: Performing a detection (201) of detection values (210) at the apparatus (1), wherein the detection values (210) are specific for measurements at different measuring points and at different apparatus components (120) of the apparatus (1), Performing a transmission (202) of the detected detection values (210) to a processing component (300), Providing an apparatus information (211) about a specification of the apparatus (1) and/or the measurements, wherein providing the apparatus information (211) is performed at the processing component (300) to provide the transmitted detection values (210) with the apparatus information (211).

The invention relates to a method (100) for processing operating data of a flow arrangement (2) of an apparatus (3) comprising a first conveying line (10) having a first flow resistor (11) and a second conveying line (20) having a second flow resistor (21) and being connected in parallel to the first conveying line (10) for a fluid flow (40) in the flow arrangement (2). Furthermore, the invention relates to a computer program product, and to a flow system (1).

A construction machine includes a bidirectionally tiltable type hydraulic pump 2, a hydraulic cylinder 1 having a cap chamber 1e and a rod chamber 1f, a first flow path 11 connecting the hydraulic pump 2 and the cap chamber 1e, a second flow path 12 connecting the hydraulic pump 2 and the rod chamber 1f, a discharge flow path 16 branched from the first flow path 11, a discharge valve 32 that is disposed in the discharge flow path 16 and controls a discharge rate of hydraulic working oil from the cap chamber 1e to the discharge flow path 16, an operation device 54 that instructs an action of the hydraulic cylinder 1, and a controller 56. The controller 56 controls the hydraulic pump 2 and the discharge valve 32 such that at least a part of hydraulic working oil discharged from the cap chamber 1e is discharged to the discharge flow path 16 when an operation amount of the operation device 54 lies within a fine operation region during a pulling action of the hydraulic cylinder 1 in a state that a load is applied in a contraction direction. Accordingly, operability improves during fine operation of the pulling action of the hydraulic cylinder in the state that the load is applied in the contraction direction.

An abnormality diagnosis method is targeted at a hydraulic device which includes a hydraulic pump and a driven device driven by the hydraulic pump. The method includes calculating a frequency distribution with regard to a deviation between a normal value of an output parameter corresponding to an operation condition and an actual measurement value of the output parameter using a prediction model, and determining the presence of an abnormality if an average of the deviation exceeds a threshold. If the presence of the abnormality is determined, a factor of the abnormality is estimated based on the range of the deviation where a waveform peak of the frequency distribution exists.

A construction machine includes: one or more hydraulic pumps discharging a working fluid; an engine supplying a rotational power to the hydraulic pumps; a hydraulic line through which the working fluid discharged by the hydraulic pumps moves; a main control valve provided on the hydraulic line and controlling supply of the working fluid to a traveling device or one or more of various working devices, which require the working fluid; a bypass cut valve provided on the hydraulic line at a lower side thereof than the main control valve to open and close the hydraulic line; an automatic warm-up switch generating a warm-up operation signal for raising a temperature of the working fluid before an operation starts; and a control device performing a warm-up operation for increasing the number of revolutions of the engine and opening the bypass cut valve to increase a flow rate along the hydraulic line, when the warm-up operation signal is received from the automatic warm-up switch.

A control device for suppressing engine load fluctuation according to main pump circuit conditions, wherein an assist torque calculation task includes a target engine torque calculation task separating smooth torque components from main pump load torque and setting a minimum value of either smooth torque component or engine setting torque as target engine torque, and a subtractor calculating target assist torque based on a difference between the main pump load torque and the target engine torque, the assist torque calculation task controlling a capacity of an assist pump based on the target assist torque and controlling switching between an assist mode and a charge mode.