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.

A first MR sensor and a second MR sensor are a combination of a first magnetic resistance effect element pattern and a second magnetic resistance effect element pattern. The first MR sensor and the second MR sensor are disposed a prescribed distance apart such that, when the first MR sensor receives the greatest quantity of the magnetic field component of a magnet oriented parallel to the axial direction of a piston, the second MR sensor receives the greatest quantity of the magnetic field component of a magnet oriented parallel to the radial direction of the piston.

A system and method for detecting the location of coil open and coil short faults. The method includes obtaining an instantaneous admittance signature of each solenoid coil, sending out a periodic test signal to each valve, obtaining a new admittance signature; and calculating the coil-open and coil-short faults.

A device and method for diagnosing and configuring a hydraulic device based on a wireless local area network relates to diagnosis and configuration device technologies. The device includes a communication unit and mobile terminal. The communication unit reads hydraulic device data or changes device configuration, and process the data to generate webpage results. The mobile terminal transmits configuration requests, receives webpage results, and displays results in webpage form. The webpage results are formed by processing the acquired hydraulic device data at the communication unit side. The mobile terminal can complete the hydraulic device diagnosis and configuration, as long as it connects to the communication unit via WIFI and supports state of the art web content. The mobile terminal does not need additional installation of a matching diagnostic or configuration program, and is not limited as a specific device installed with a specific operating system; a general-purpose device may be used.

An actuator assembly for moving a valve between an open position and a closed position includes an actuator housing forming at least a portion of a chamber. The actuator assembly also includes a support plate arranged within the actuator housing. The actuator assembly further includes a diaphragm coupled to the actuator housing and the support plate, the diaphragm expanding and contracting in response to a working fluid within the chamber. The actuator assembly also includes an indicator rod extending through the chamber and out of the actuator housing, the indicator rod being removably coupled to the support plate, wherein the indicator rod is arranged within an opening formed in the support plate, the indicator rod secured to the support plate via a coupling mechanism that releases the indicator rod in response to a pressure from the working fluid between the diaphragm and the support plate.

A fluid leakage detection device includes: a rod seal provided in a cylinder head, a rod seal being configured to seal an annular gap between a piston rod and the cylinder head; a detection seal configured to seal an annular gap, a detection seal being configured to partition the detection space together with the rod seal; a communication passage in communication with the detection space; a pressure sensor configured to detect the pressure of the working oil guided through the communication passage; and a relief valve configured to release the pressure in the communication passage, wherein the detection seal is provided between the rod seal and a dust seal, the dust seal being configured to seal the annular gap by being provided in the cylinder head so as to face the outside of the cylinder tube.

A spring return hydraulic or pneumatic valve is actuated, by an actuator, from a first position to a second position. A displacement of the valve is measured. A hydraulic or pneumatic pressure of the valve actuator is measured. A spring constant of the spring is calculated based on the measured displacement and the measured pressure. The calculated spring constant is compared with a manufacturer listed spring constant.

A stick slip detection system includes: an operation data storage unit configured to store a stick slip index, the stick slip index being a ratio of a first state amount based on a displacement of a valve shaft of a valve to be diagnosed to a second state amount based on the displacement; an abnormality diagnosis unit configured to determine whether a stick slip phenomenon occurs in the diagnosis target based on the stick slip index; and a diagnosis operation control unit configured to, when a stepwise change in a control command value in an intermediate opening degree of the valve to be diagnosed is detected, stop a determination operation of the abnormality diagnosis unit. The present disclosure makes it possible to easily reflect knowledge of an expert with respect to a diagnosis target such as a valve in the stick slip detection system and method.

A fluidic control system (1) for controlling a vehicle, which includes a controller (2) and a closed fluidic circuit. The circuit includes a pump (3) for pressurizing fluid in the circuit, valve means (40, 50, 60), an actuator (4, 5, 6) and a precharge accumulator (7). The valve means (40, 50, 60) is fluidly connected to the inlet and outlet of the pump (3) and the actuator (4, 6) is fluidly connected to the valve means (40, 50, 60) for selectively receiving pressurized fluid therefrom. The precharge accumulator (7) includes a movable member (73, FIG. 2) that describes a variable volume (71) fluidly connected to the circuit between the valve means (40, 50, 60) and the inlet of the pump (3). The system (1) also includes a sensor (70) for determining the position of the movable member (73) for estimating the quantity of fluid and/or detecting an abnormal pressure variation within the circuit.

An actuator system includes a piston-cylinder arrangement including a piston that is movable with respect to a cylinder. A first flow path is in fluid communication with the piston-cylinder arrangement and a second flow path is in fluid communication with the piston-cylinder arrangement. A control system is operable to fluidly connect the first flow path to a source of high-pressure fluid and to connect the second flow path to a drain to move the piston in a first direction. A pressure sensor is fluidly connected to the first flow path and is operable to measure sufficient pressure data during the movement of the piston to generate a pressure versus time curve. The control system is operable to compare the generated pressure versus time curve to a known standard pressure versus time curve stored in the control system to determine the condition of the piston-cylinder arrangement.