A method is provided for compensating for the flow rate of a variable capacity-type hydraulic pump such that, when a manipulation lever is manipulated, a discontinuous section, which has no change in the discharge flow rate of the hydraulic pump, is eliminated.

A valve group includes an inlet module and at least one service module connected to the inlet module, the inlet module having a housing, a pressure port, a pressure gallery, a tank port, a tank gallery, a spool movable in the housing to interrupt in a first position a connection between the pressure port and the pressure gallery and to connect in a second position the pressure port and the pressure gallery. A first pressure transducer is provided to detect a first pressure in the pressure gallery and a second pressure transducer is provided to detect a second pressure in the tank gallery, the pressure transducers being connected to a controller determining the position of the spool based on the pressures read from the pressure transducers.

A self-contained pressure compensation system and a control method thereof are provided, wherein the self-contained pressure compensation system comprises an oil supply device, a pressure compensation device, a power unit associated with the pressure compensation device, and a switch control device, the pressure compensation device supplies oil to the power unit and detects a change in a chamber pressure of itself in real time, the switch control device triggers the oil supply device to supply oil to the pressure compensation device if the chamber pressure is less than a predetermined first threshold and triggers the oil supply device to stop supplying oil to the pressure compensation device if the chamber pressure is greater than a predetermined second threshold. The invention can detect a chamber pressure of the pressure compensation device in real-time and can achieve automatic oil refilling, and can provide pressure compensation for the power unit effectively.

The present disclosure relates to diagnosing and locating fluid leakage within a pneumatic system (5) using a minimal amount of pressure sensors (55, 75, 89). In general, each branch (51, 71, 85) of a pneumatic system (5) includes an associated pressure sensor (55, 75, 89) and in accordance with how the pneumatic components (57, 59, 61, 77, 91, 93, 95) associated with the pneumatic branch (51, 71, 85) are toggled and monitored, leaks can be detected and located within the branch (51, 71, 85) using a minimal amount of pressure sensors (55, 75, 89). More specifically, pressure and pressure decay may be measured by the sensors (55, 75, 89) within a branch (51, 71, 85) while the pneumatic components (57, 59, 61, 77, 91, 93, 95) are in a particular configuration. The configuration is thereafter changed, and pressure and pressure decay are again measured by the sensors (55, 75, 89). The results of these two measurements may enable the pneumatic system (5) to derive the presence and location of a leak.

A method is provided for the simultaneous detection, localization, and quantification of leaks and obstructions in a gas network under pressure or vacuum. The gas network includes: one or more sources of compressed gas or vacuum; one or more consumers or consumer areas of compressed gas or vacuum applications; pipelines or a network of pipelines to transport the compressed gas or vacuum from the sources to the consumers, consumer areas or applications; a plurality of sensors providing one or more physical parameters of the gas at different times and locations within the gas network. The gas network is further provided with controllable or adjustable relief valves, controllable or adjustable throttle valves and possibly one or a plurality of sensors capable of monitoring the status or state of the relief valves and/or throttle valves.

A system and method is provided for monitoring a hydraulic power system having at least one light emitter and a button. The method includes powering on the hydraulic power system, receiving an actuation at the button and detecting a release of the button after a first time interval, and entering a diagnostic state. The method further includes retrieving a code and displaying the code by turning on the emitter in a first pattern. In some embodiments, a system and method is provided for regulating a temperature of a hydraulic power system. In some embodiments, a system and method is provided for controlling operation of a hydraulic torque wrench.

A fluid pressure actuator is provided with an actuator main portion whose shape is changed by the expansion or contraction of a cylindrical tube expanded and contracted by the pressure of fluid, and a detection unit for detecting the length L of the actuator main portion along the longitudinal direction of the tube.

A system for automatic calibration of an actuator, where the system has an actuator and a computer, and the computer further includes a PID controller. A sensor connected to the actuator transmits values representing the motion of the actuator to the input of the PID controller. The computer is programmed to compare the values representing the motion of the actuator to the output of the PID controller, thus outputting an error signal representing the difference between the output of the PID controller and the values representing the motion of the actuator. The computer stores this difference as a calibrated set point for the actuator when the difference is less than a predetermined amount. This calibrated set point is used to initialize the operation of a machine propelled by the actuator.

A fluid leakage detection system includes: a measurement unit configured to detect leakage of working oil in a hydraulic cylinder; and a controller configured to acquire a measurement result from the measurement unit, wherein the controller diagnoses that a battery depletion has been caused in a battery in a case in which it is determined that a data from the measurement unit has not been acquired and it is determined that the battery of the measurement unit has been in a low-remaining-battery-level state, and the controller diagnoses that a communication abnormality has been caused in a first communication part of the measurement unit in a case in which it is determined that the data from the measurement unit has not been acquired and it is determined that the battery has not been in the low-remaining-battery-level state.

A failure detection apparatus for a hydraulic system, to a hydraulic, failure detection-capable system, and to a method of operating a failure detection apparatus. The failure detection apparatus comprises a monitoring and failure detection unit that receives first and second pressure values from first and second pressure sensors and comprises a failure detection unit that detects a failure of at least one hydraulically operated device when a 2-tuple of a plurality of 2-tuples is within a first and outside a second predetermined tolerance range of relative pressure values, and wherein the failure detection unit 260 detects a failure of the pump when a 2-tuple of the plurality of 2-tuples is outside the first predetermined tolerance range of relative pressure values.