4122results about "Fluid-pressure actuator testing" patented technology

A system and method to diagnose the operational health of a hydraulic accumulator are provided. The system can include a hydraulic accumulator selectively coupled to a hydraulic actuator, such as a swing motor. The accumulator can be charged by movement of the actuator. A pressure sensor can be associated with the accumulator to determine an accumulator pressure. A controller can be connected to the pressure sensor. The controller can determine a charge curve based on a relationship between an actuator operational parameter associated with the actuator movement and the accumulator pressure. The controller can compare the charge curve to a previously defined charge curve or range to determine an error between the charge curve and the previously defined charge curve or range. The degree of the error can be associated with the operational health of the accumulator, and if too large, the operator may be notified of the status.

PCT No. PCT / FI97 / 00359 Sec. 371 Date Dec. 4, 1999 Sec. 102(e) Date Dec. 4, 1999 PCT Filed Jun. 9, 1997 PCT Pub. No. WO97 / 48026 PCT Pub. Date Dec. 18, 1997A method and a valve apparatus for surveying the condition of a control valve. The position of the valve (101) is adjusted by means of an actuator (103) controlled by an electropneumatic positioner (104) and operated by means of pressure medium. The operation of the valve is monitored by sensors (109, 110, 107) that read the readings from the control signal, the input pressure of the positioner, the difference between the input and output pressure of the actuator, and the position of the valve. A fault causing a deviating reading will be located by using the readings given by the sensors and deduction rules stored in the microprocessor of the actuator. In an initial situation, when the valve is in balance state, the readings given by the sensors are stored at least from the control signal, valve position and the difference between the input and output pressure of the actuator. When the operation is continued, the readings given by the sensors are compared with the readings of the initial situation. If the deviations exceed certain limit values and remain there continuously for a certain period of time, a fault message will be given that indicates the location of the fault.

A valve body has an elongated bore in communication with an inlet port and an outlet port. A valve element is movable within the bore between deactuated and actuated positions. A valve sensor generates a sensor signal indicative of an instantaneous parameter of the valve that changes between the deactuated and actuated positions. A logic unit receives the sensor signal and a pilot command signal that actuates the valve. A predetermined change in the pilot command signal causes the logic unit to determine a cycle parameter responsive to a time period between two predetermined events. At least the beginning or end of the time period corresponds to a predetermined value of the sensor signal. The individual determinations of the cycle parameter are accumulated to obtain an expected cycle parameter. The logic unit generates an indication signal when the cycle parameter exhibits a predetermined variance from the expected cycle parameter.

Provided is a servovalve system for regulating fluid flowing within a fluid circuit. The servovalve system comprises a housing, a spool slidably disposed within the housing, a stepper motor operatively connected to the spool, and a controller and a position sensor electronically connected to the stepper motor. The controller generates driver signals representative of a desired amount of stepper motor rotation in order to cause the stepper motor to effectuate spool motion relative to the housing. The position sensor senses an actual amount of stepper motor rotation and generates a quantity of position signals representative thereof. The controller determines a signal ratio of the quantity of the position signals to the quantity of the driver signals and generates a diagnostic signal when the signal ratio reaches a threshold value representative of a predetermined level of mechanical resistance of spool motion relative to the housing.

A method and apparatus for determining the service life of a cyclic system the method including the steps of determining at least one characteristic of the system to determine a characteristic value and determining a cycle time of the system. The at least characteristic value is applied to an algorithm in which the characterisitic value is integrated to determine a diagnostic value, and comparing the diagnostic value to a predetermined value to determine the performance status of the system. The apparatus including a sensor for determining a system characteristic and a calculating unit operatively connected to the sensor. The calculating unit including circuitry for performing a mathematical integration on the system characteristic to determine a diagnostic value and comparing the diagnostic valve to a predetermined value to determine the performance status of the system. A notification device operatively connected to the calculating unit for indicating the operational status of the system.

The disclosure concerns a method for monitoring at least one component to be monitored in a hydraulic circuit filled with a working fluid, the hydraulic circuit comprises at least one pump for circulating the working fluid, wherein the method comprises:—changing an operational state of at least one first component in the hydraulic circuit such that a working point of the at least one component to be monitored changes to a predetermined working point;—performing at least one measurement for monitoring the at least one component to be monitored. Further, the disclosure concerns a monitoring device for monitoring at least one component to be monitored in a hydraulic circuit being filled with a working fluid. Further, the disclosure concerns a fluid turbine comprising at least one fluid rotor, wherein the fluid rotor is adapted to convert kinetic power of a fluid into a rotation, the fluid turbine further comprising a hydraulic circuit filled with a working fluid.

A system and method for predicting impending pump failure in a hydraulic system is disclosed. The system measures and compares the running and moving volumetric deficiencies of the hydraulic system as a whole and if they are not within range of each other by a predetermined threshold, the system determines that at least one of the pumps in the system is about to fail. If such a determination is made by the system, the pump displacement is at standby of each pump is then calculated and the pump with the greatest displacement at standby is determined to be the pump approaching failure. Once the pump approaching failure is identified, a signal is generated to apprise the operator or other entity to enable corrective action to be taken.

In a hydraulic machine, hydraulic pump failure is detected and the pump lifespan is estimated before the pump failure occurs. The discharge pressure 122, oil temperature 126, and drain filter differential pressure 120 are measured, a correlative relationship 128 between the filter differential pressure and the discharge pressure is determined, and a representative filter differential pressure 130 is calculated from this correlative relationship. Using an oil temperature-differential pressure correlation function, the representative differential pressure value 130 is corrected so that the variable component 132 caused by the oil temperature 126 is eliminated therefrom. The long-term trend and the short-term trend of the increase over time of the corrected differential pressure is calculated. A pump failure is predicted or the pump lifespan is estimated based on the degree of deviation between the long-term trend and the short-term trend.

In a hydraulic machine, hydraulic pump failure is detected and the pump lifespan is estimated before the pump failure occurs. The discharge pressure 122, oil temperature 126, and drain filter differential pressure 120 are measured, a correlative relationship 128 between the filter differential pressure and the discharge pressure is determined, and a representative filter differential pressure 130 is calculated from this correlative relationship. Using an oil temperature-differential pressure correlation function, the representative differential pressure value 130 is corrected so that the variable component 132 caused by the oil temperature 126 is eliminated therefrom. The long-term trend and the short-term trend of the increase over time of the corrected differential pressure is calculated. A pump failure is predicted or the pump lifespan is estimated based on the degree of deviation between the long-term trend and the short-term trend.

The invention relates to a servo valve test system. By adopting a cartridge valve to automatically switch static and dynamic oil lines, the servo valve test system can realize the full automatic one-step test and intelligent analysis of the static properties and the dynamic properties of an electro-hydraulic servo valve, improves the test efficiency of the electro-hydraulic servo valve, and increases the accuracy of the test results. Strictly based on the test standard of the electro-hydraulic servo valve GB / T15623-1995, the whole test method completes all the detection tests of the servo valve, and automatically displays and outputs the test results. The servo valve test system mainly comprises a hydraulic test system, an electrical control system and a data acquisition and processing system, wherein a servo valve to be tested is connected with the hydraulic test system and the electrical control system; a main oil line of the hydraulic test system is automatically switched to the dynamic oil line and the static oil line by a cartridge valve assembly, and the hydraulic test system is also provided with a dynamic cylinder for detecting the servo valve to be tested; and the data acquisition and processing system is connected with the electrical control system and the hydraulic test system.

The invention discloses a multi-working-condition comprehensive simulation test system for reciprocating seal of an aviation actuator. The multi-working-condition comprehensive simulation test system comprises a test actuator, a reciprocating driving loading system and a hydraulic system, wherein the reciprocating driving loading system is connected with a piston rod of the test actuator; the hydraulic system is connected to an oil inlet / outlet of a cylinder body; the test actuator comprises an end cover, the piston rod and the cylinder body; the reciprocating driving loading system comprises an electric cylinder, a transmission shaft, a transmission vibration isolating device, a force sensor and an LVDT sensor, and the transmission shaft is connected with the force sensor through the transmission vibration isolating device; and the hydraulic system comprises a pump source module, a pressurization module, a pressure maintaining module and a pipeline heater. By using the multi-working-condition comprehensive simulation test system, multi-working-condition comprehensive conditions such as high pressure, wide temperature range, variable speed and airborne vibration of the aviation actuator can be effectively simulated, and the friction force character of multi-type shaft seal of single piston rod and the leakage rate obtained after repeated reciprocation can be accurately measured under various working conditions; and the multi-working-condition comprehensive simulation test system has the characteristics of convenience in use, operation stability, test accuracy, long service life and the like.

The invention discloses an energy-conservation and low-impact hydraulic cylinder test testbed hydraulic control system. The system comprises a constant pressure variable pump, two electromotors, two electromagnetic unloading overflow valves, six check valves, two energy accumulators, an electrohydraulic proportional direction valve, two speed regulating valves, four ball valves, an oil supplementing pump, a proportional throttle valve, an electromagnetic reversing valve, a loading hydraulic cylinder, six pressure sensors, two temperature sensors, a displacement sensor, a force sensor, two travel switches, six pressure measuring connectors, six pressure gages, a heater, a liquid level liquid temperature gage, a filter and an oil tank. The energy-conservation and low-impact hydraulic cylinder test testbed hydraulic control system has the advantages that stable energy is provided for low-impact control over the speed of a tested hydraulic cylinder while energy is conserved, low-impact stable control over the loading force is achieved, meanwhile, the actual work condition that loads of the hydraulic cylinder probably change continuously in work can be simulated, all the work conditions of the loads of the hydraulic cylinder can be simulated, and power input is reduced.

The invention discloses application of deep learning based on fuzzy processing in fault diagnosis of hydraulic equipment. The application comprises the following steps of: (1) introducing a time label and fuzzy weight to pre-process operation monitoring data of the hydraulic equipment, and dividing the operation monitoring data into a training data set and a test data set; (2) taking the training data set as an input vector of a sparse self-coding network to carry out non-supervision pre-training; (3) taking label data and no-label data as an input vector training Softmax classifier of a Softmax classifier; (4) utilizing a BP algorithm to carry out fine adjustment on deep learning network parameters; and (5) carrying out intelligent diagnosis on a fault condition. According to the application disclosed by the invention, firstly, a method of introducing the time label and fuzzy weight is adopted to carry out pre-processing on data; then, sparse self-coding is used to complete high-level feature extraction of sample data, and the Softmax classifier is used to carry out classifying diagnosis on an equipment fault state to construct an ICM model; and finally, the BP algorithm is utilized to carry out fine adjustment on global optimal parameters of the whole network, so that intelligent diagnosis on the fault state is realized.

A hydraulic system includes a plurality of pumps that provide pressurized fluid to a plurality of hydraulic actuators some of which work more that others. That system is controlled by producing a usage value for each of the plurality of pumps which indicates an amount that the respective pump has worked. One of the pumps is assigned to each hydraulic actuator in response to the usage values. The pumps with lower usage values are assigned to hydraulic actuators which work more, so as to equalize the use of each pump. The assignment of pumps to hydraulic actuators changes with changes in the usage values for the plurality of pumps. When a given one of the plurality of hydraulic actuators is to operate, hydraulic fluid is routed from the assigned pump to that given one of the plurality of hydraulic actuators.

A system and methods for proportionally controlling hydraulically actuated downhole flow control devices using derived feedback control. The system comprises a downhole flow control device with a moveable element in a stationary housing. The moveable element is actuated by a balanced hydraulic piston. Hydraulic lines are fed to either side of the piston to effect actuation in either direction. A processor controlled, surface mounted hydraulic system supplies fluid to the piston. A pressure sensor measures supply pressure to the piston and a cycle counter indicates pump cycles and both sensors generate outputs to the processor. The downhole moveable element is cycled between end stops until successive moveable element breakout pressures are within a predetermined value as measured by the surface pressure sensor. A relationship is then derived between moveable element movement and pumped fluid volume and the relationship is used to move the moveable element to a predetermined position to control flow.

The invention discloses a fault location method based on a residual and a double-stage Elman neural network for a hydraulic servo system, comprising the following steps of: obtaining the input / output signals of the hydraulic servo system in a normal working state, an electronic amplifier fault state and a leakage fault state, training a fault observer by virtue of the input / output signal in the normal state, and obtaining a real-time residual signal by the fault observer at first, and then training a state follower in real time and on line to obtain a network connection weight corresponding to the real-time signal, and training an RBF (radial basis function) fault locator by using the time-domain characteristic value of the residual signal and the network connection weight as the training input samples of the RBF fault locator. Both of the fault observer and the state follower are realized by the improved Elman network. Whether the system has a fault or not at present can be judged by comparing the time-domain characteristic value with a fault threshold, and the type of the fault can be obtained by the fault locator. The fault location method disclosed by the invention realizes fault location for the hydraulic servo system, and has high location accuracy and engineering applicability.

The invention relates to an experimental device and an experimental method for multi-source information fusion for fault diagnosis of a hydraulic device. The device comprises the following elements: a variable plunger pump, a gear pump, two motors, two suction filters, five throttle and stop valves, two electromagnetic relief valves, an electromagnetic proportional relief valve, two pressure meters, an energy accumulator, two sets of combined sensors, a three-position four-way electromagnet directional valve, a hydraulic motor and a cooler. The experimental device can simulate eight typical running states (faults) of the hydraulic device, including low efficiency, oil and liquid pollution, air suction, leakage, oil pump fault, relief valve failure, motor failure and mechanical failure and can perform cluster analysis and fusion diagnosis to characteristics of the eight faults through a self organizing maps neural network.

A system for a pneumatically-powered vitrectomy machine includes an output port, a venting valve, a venting manifold, a pressure transducer, and a controller. The output port provides pressurized gas to a vitrectomy probe. The venting valve is located close to the output port. The venting manifold fluidly connects the venting valve to a venting port. The venting port vents pressurized gas from the venting manifold. The pressure transducer is located near the output port. The pressure transducer is configured to read a pressure of a gas near the output port. The controller is adapted to receive information about the pressure and activate the venting valve. When the information received from the pressure transducer indicates a fault condition, the controller directs the venting valve to open.

A method and apparatus of diagnosing leakage in a fluid power system including a fluid supply line operatively connected to a plurality of valves which are connected to a plurality of actuators. Flow signals generated by a flow sensor disposed in the supply line are processed to obtain fluid consumption over time values and signals used to change the state of the plurality of valves are processes to determine a plurality of episodes. Each of the plurality of episodes corresponds to a pressurization of a particular branch of a particular actuator. The flow signals and the signals used to change the state of the valves are combined to calculate a change in air consumption value for each valve change of state. The change in air consumption values for each episode are compared to a predetermined reference value to determine any deviation corresponding to a particular one of the plurality of episode. The one of the plurality of episodes and corresponding pressurized branch with the greatest deviation is identified. A signal is generated indicating both that a leak is present in the system and the branch responsible for the leak.

The invention discloses an online fault diagnosis method for a hydraulic system. A sensor network (2) and an industrial personal computer (3) are used for acquiring a signal of a key position of the hydraulic system (1). Meanwhile, a system model is established for the hydraulic system (1), and fault injection simulation is carried out to obtain a simulation result serving as fault simulation data in a fault simulation module (6). The key characteristic information of the data provided by a data reading module (4) is found by a data characteristic extraction module (5), and fault diagnosis is carried out through a fault diagnosis module (7). A fault positioning module (8) can be used for positioning the fault according to fault information obtained by the fault diagnosis module (7), and providing a fault diagnosis result, fault causes, a detection flow and fault elimination measures, which are all displayed on a human-computer interface (9). According to the method, the false fault alarm rate is reduced, the capacities such as early warning are improved, and the method plays an important role in improvement of the reliability of the hydraulic system of product equipment.

The invention provides a timing control system and a method for an electric-hydraulic proportion flux valve. By measuring the maximum motion speed of a hydraulic executing component, and the maximum motion current and the minimum motion current of the valve core of the electric-hydraulic proportion flux valve, and by using the maximum motion speed, the maximum motion current and the minimum motion current of the valve core of the electric-hydraulic proportion flux valve, the correspondence between the movement speed of the hydraulic executing component and the current of the valve core can be obtained. By the correspondence, the valve core current corresponding to the given speed of the system can be acquired. By the valve core current corresponding to the given speed of the system, a valve core current controlling loop can be directly driven. The anticipatory speed controlling method improves the responding quality and the control precision of the forward passage of the timing control system greatly, reduces the adjusting volume of the feedback passage of the speed, and achieves the purpose of improving the quality of the closed loop control.

A measuring and controlling system of an electro-hydraulic servo valve comprises a hardware part and a software part, wherein the hardware part comprises sensors, an acquisition card, a signal conditioning circuit and a computer; the software part comprises three test modules which are respectively of an electro-hydraulic servo valve static characteristic module, and a PID closed-loop control module and an electro-hydraulic servo valve dynamic characteristic module. Firstly, signals of the sensors pass through a hardware conditioning circuit and then are subjected to the A / D (Analog to Digital) conversion through the acquisition card to be converted into digital signals; signals compiled by the software are subjected to the D / A (Digital to Analog) conversion through the acquisition card and then serve as control signals of the servo valve; test functions are realized through all modules in a program; the measuring and controlling system has the advantages that the environment of the measuring and controlling system is effectively improved, the test cost of the electro-hydraulic servo valve and the impact of the personal factors are reduced, operation steps are greatly simplified, and the accuracy and efficiency of testing are improved.

A valve body has an elongated bore in communication with an inlet port and an outlet port. A valve element is movable within the bore between deactuated and actuated positions. A valve sensor generates a sensor signal indicative of an instantaneous parameter of the valve that changes between the deactuated and actuated positions. A logic unit receives the sensor signal and a pilot command signal that actuates the valve. A predetermined change in the pilot command signal causes the logic unit to determine a cycle parameter responsive to a time period between two predetermined events. At least the beginning or end of the time period corresponds to a predetermined value of the sensor signal. The individual determinations of the cycle parameter are accumulated to obtain an expected cycle parameter. The logic unit generates an indication signal when the cycle parameter exhibits a predetermined variance from the expected cycle parameter.

The invention discloses a hydraulic pipeline vibration test simulation experiment platform which comprises a vibration exciting unit, a hydraulic power unit, a sensor detection system, a control unit and a signal collecting and processing unit. The vibration exciting unit comprises a workbench and an industrial control computer, two vibration platforms are placed on the workbench, a to-be-tested pipeline is fixed on the vibration platforms, an accelerometer, a strain gauge and an optical fiber grating sensor are mounted in the to-be-tested pipeline, the hydraulic power unit is provided with a proportional flow valve, a proportional overflow valve and a digital switch valve, the sensor detection system comprises a temperature sensor and a pressure sensor which are both arranged on the vibration platforms, and the signal collecting and processing unit is connected with the sensor detection system and a sensor in the hydraulic power unit. The hydraulic pipeline vibration test simulation experiment platform can simulate vibration of a hydraulic pipeline mounting base and changing of temperature, flow and pressure of fluid in a pipeline, and has wide application prospect in the field of petrochemical industry, water conservancy, machinery and aerospace.

The invention discloses an online oil filling and purifying device for hydraulic equipment. The main design points are that: an oil tank is provided with a vacuumization control system; the oil tank is divided into an absolute oil tank and a dirty oil tank; the absolute oil tank is provided with an oil inlet pipeline; the dirty oil tank is provided with an oil drain valve; an online circulating filtration system comprises a dirty oil pipeline communicated with the dirty oil tank and an absolute oil pipeline communicated with the absolute oil tank; the dirty oil pipeline is provided with a dirty oil electromagnetic control valve; the tips of the dirty oil pipeline and the absolute oil pipeline are respectively provided with a dirty oil pipeline quick connector and an absolute oil pipeline quick connector which are communicated with the oil tank of the hydraulic equipment; the dirty oil pipeline is communicated with the absolute oil pipeline through an isolation electromagnetic valve, aone-way valve and a gear pump; and a pressure filter is arranged in the absolute oil pipeline. The online oil filling and purifying device for the hydraulic equipment designed in the invention has the characteristics of high integration degree, complete functions, compact structure, and high maneuverability and maintainability.

A method and apparatus for determining the operating health of a hydraulic system are provided. The method may include the steps of determining a plurality of operating parameters of the hydraulic system during operation of the hydraulic system, determining an estimated working condition value of the hydraulic system, modifying the estimated working condition value as a function of the operating parameters, and determining the operating health of the hydraulic system as a function of the working condition value. In one method, the working condition value may be indicative of an effective bulk modulus value of an operating fluid within at least part of the hydraulic system.

A system and methods for proportionally controlling hydraulically actuated downhole flow control devices using derived feedback control. The system comprises a downhole flow control device with a moveable element in a stationary housing. The moveable element is actuated by a balanced hydraulic piston. Hydraulic lines are fed to either side of the piston to effect actuation in either direction. A processor controlled, surface mounted hydraulic system supplies fluid to the piston. A pressure sensor measures supply pressure to the piston and a cycle counter indicates pump cycles and both sensors generate outputs to the processor. The downhole moveable element is cycled between end stops until successive moveable element breakout pressures are within a predetermined value as measured by the surface pressure sensor. A relationship is then derived between moveable element movement and pumped fluid volume and the relationship is used to move the moveable element to a predetermined position to control flow.

Method and apparatus for performing diagnostics in a pneumatic control loop for a control valve. Pressure and displacement sensors normally provided with a positioner are used to detect operating parameters of the control loop. A processor is programmed to receive feedback from the sensors and generate fault signals according to a logic sub-routine. The logic sub-routine may include calculating mass flow of control fluid through spool valve outlet ports and comparing other operating parameters of the control fluid to detect leaks and blockages in the control loop. Once a fault is detected, the location of the root cause of the fault may be identified by characterizing operating parameters of the control loop at the time of the fault.

The invention discloses a hydraulic cylinder test bench load simulation device and a control method thereof. The hydraulic cylinder test bench load simulation device comprises a test bench frame, a control system, a loading hydraulic cylinder and a tested hydraulic cylinder, wherein the control system comprises an industrial personal computer, a PLC (programmable logic controller), a positional system control module and a loading system control module, the industrial personal computer sends a displacement signal to the PLC to drive the tested hydraulic cylinder to run, a displacement sensor detects the displacement signal of the tested hydraulic cylinder, the displacement sensor feeds the displacement signal back to the positional system control module so as to adjust displacement of the tested hydraulic cylinder on the one hand, and sends the displacement signal to the industrial personal computer on the other hand, the industrial personal computer converts the displacement signal into a simulation resultant force signal, and sends the simulation resultant force signal to the loading system control module so as to drive the loading hydraulic cylinder to perform opposite vertex loading on the tested hydraulic cylinder, and simultaneously a pull pressure sensor detects a pull pressure signal, and feeds the pull pressure signal back to the loading system control module after comparing the pull pressure signal with the simulation resultant force signal so as to form force negative feedback control. The hydraulic cylinder test bench load simulation device and the control method thereof achieve high automation of the hydraulic cylinder test bench load simulation device, and is high in accuracy and strong in practicability.

The invention relates to a loading device of a hydraulic motor test board, which is characterized in that a high-pressure oil pump which is connected with an oil tank is connected with an electro-hydraulic reversing valve, a bi-direction retaining throttling valve and a test motor oil inlet through a high-pressure filter and an oil inlet retaining valve, a test motor oil outlet forms a test loop with an oil return retaining valve and an oil return filter oil return box after being connected with a remote counterbalance overflow valve, a flow-rate sensor, through the bi-direction retaining throttling valve and an electro-hydraulic reversing valve oil outlet. A loader is formed by joining a loading motor and a testing motor respectively with a rotation speed torque instrument through a coupling joint, at the same time, a low-pressure pump which is connected with the oil tank enters two ends of the loading motor through two retaining valves, the testing motor rotates to drive the loading motor to rotate, the oil outlet retaining valve is automatically closed, and the outlet oil forms a loading circuit through the counterbalance overflow valve, the remote overflow valve, the oil return retaining valve and the oil return filter oil return box. The loading motor is used for substituting an original magnetic powder loader, so the size is greatly reduced, the energy consumption is reduced, the remote control adjustment is convenient for test personnel to work, the loading force is large, torque of 60000 N.m can be tested, the testing range is wide, and the practicability is strong.