2006results 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.

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.

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.

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.

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.

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.

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 discloses a fault detection, diagnosis and performance evaluation method for a redundant aileron actuator. According to the method, fault detection, diagnosis, evaluation and real-time detection of the actuator are performed by means of an input order signal, an output displacement signal, a force motor current signal and aerodynamic loading data of the actuator; the fault detection is realized by a two-stage neural network, a first neural network is used as a system observer and is matched with actual output to acquire a residual error, and a second neural network outputs a self-adaptive threshold value synchronously; the fault detection is realized by the system observer and a force motor current observer; a time domain feature is extracted from a residual error signal and output to a self-organizing mapping neural network, and a minimum quantization error is acquired and normalized to a health degree, so that the actuator performance is evaluated; and on the basis of fault detection, the aerodynamic loading data is introduced, by means of a specific input order spectrum, the system observer and the neural network with the self-adaptive threshold value are trained, and the real-time fault detection is realized.

The invention discloses an energy-efficient hydraulic power supply driven by a permanent magnet servo motor, which comprises the permanent magnet servo motor, a servo controller, a hydraulic oil pump (comprising a gear oil pump, a vane pump, and a plunger pump), a sensor and the like. An oil pump is driven by the high-efficiency permanent magnet servo motor which has good mechanical characteristic, large overload magnification, and high speed regulation performance; a system for redundancy monitoring of system flow and pressure by pressure-flow double closed loop control and the voltage and current of the motor is adopted; and an oil temperature compensation function is realized. According to different hydraulic pressure load working conditions, three working modes of pressure self-adaption, flow self-adaption, and power self-adaption are provided, and each working mode is optimized by adopting different control strategies. Therefore, the energy-efficient hydraulic power supply has the advantages of wide application range, high system efficiency, high low-speed stability, quick response, accurate speed regulation and the like.

Methods, systems, and articles of manufacture consistent with the present invention provide for detecting a leak in a hydraulic fluid system having a reservoir and a conduit operatively connected to the reservoir. The fluid may reside in the reservoir, the conduit, or both. A current level of the fluid in the reservoir is sensed. A determination is made as to whether the current level is less than a leak detection level. When it is determined that the current level is greater than the leak detection level, a current temperature of the fluid is sensed and the leak detection level is updated based on the current temperature of the fluid so that thermal expansion of the fluid in the system is considered in detecting and isolating a leak.

The invention discloses a comprehensive test platform for the dynamic performance of a hydraulic cylinder of an engineering machine. The comprehensive test platform for the dynamic performance of the hydraulic cylinder of the engineering machine comprises a test platform body, a hydraulic system and an electrical test control system. The hydraulic system comprises a drive system unit and a loading system unit. The drive system unit comprises a first hydraulic pump, a first filter and three liquid inlet valve banks. Oil outlets of the three liquid inlet valve banks are connected with an oil inlet of the tested hydraulic cylinder. The loading system unit supplies oil to a loading hydraulic cylinder. The electrical test control system controls all the valve banks of the hydraulic system according to feedback signals. According to the comprehensive test platform for the dynamic performance of the hydraulic cylinder of the engineering machine, a drive system, a loading system and a gas-liquid supercharging system which are independently arranged are used for meeting test and control needs under different loads and different working conditions; and the comprehensive test platform also utilizes the feedback signals to control the test process, when the oil pressure, the flow, the filter precision, the system temperature and other indexes are not at the normal level, the system gives out an alarm to remind people and stops, and therefore system operation reliability is guaranteed.

The invention discloses an airplane hydraulic test distributed test system and a method thereof, belonging to the technical field of measurement and control. The test system comprises a data acquisition instrument module (1), a test controller (2), a signal conditioner (3), a network switch (4), an LXI instrument control data bus (5), a field data module (6), an interface conversion module (7), a field data bus (8), a series communication data bus (9) and test software and is characterized in that a plurality of data buses are simultaneously used, and various data acquisition modules are adopted in the test system to finish the data acquisition in the measurement of various signals and the long-line transmission of the measured signals. The system of the invention has compact and simple structure, small space size, reliable operation, high test accuracy and favorable expansibility and tailorability.

The invention provides a health evaluation method for a hydraulic system based on a fault observer and SOM (self-organized mapping). The method includes: firstly, training the fault observer by the aid of input and output signals of the hydraulic system in a normal operation state to acquire residual signals in the normal state; secondly, acquiring residual signals of a certain component in a degenerate state through the fault observer by the aid of input and output signals of the degenerate component in the system; thirdly, extracting time-domain features of the residual signals in the two states and building a self-organized mapping model by the aid of residual features in the normal state; and finally, inputting residual features of the degenerate component to the self-organized mapping model to acquire the health degree of the hydraulic system in the corresponding states, and judging whether the current hydraulic system can continue running or not by the aid of the lowest health threshold value. The health evaluation method is used for evaluating health of the hydraulic control system in real time, is fine in evaluation effect, reduces dependency on historical data, and has engineering practicability.

The invention pertains to a diagnostic device for a fluidic device (11, 12, 23), in particular for a valve array and or a maintenance unit. Furthermore, the invention pertains to a fluidic device (11, 12, 23) equipped with said diagnostic device. The diagnostic device preferably can be locally attached to the fluidic device (11, 12, 23). It features a diagnostic module (34) to determine at least one wear parameter (38b-40b,44) causing wear on the fluidic device (11,12,23) and for reporting of at least one wear status ascertained on the basis of the at least one wear parameter (38b-40b,44).

In a method for controlling a valve system controlling an actuator, the first direction of motion of the actuator is controlled solely by the first and the second valve series; or, its second direction of motion is controlled solely by the third and the fourth valve series; and an error caused by a fault situation in the control of the actuator is compensated for by using, for the control of the first direction of motion, also the third valve series, the fourth valve series, or both of them; or, an error in the control of the actuator caused by a fault situation is compensated for by using, for the control of the second direction of motion, also the first valve series, the second valve series, or both of them. In the method, for searching for faults in the valve system controlling the actuator, the pressure of the inlet port of the valve system, the pressure of the first working port, and the pressure of the outlet port are determined; one or more valves of the first valve series and one or more valves of the second valve series are opened; the measured pressure of the first working port is compared with a situation corresponding to a system operating correctly; and on the basis of the comparison it is concluded whether the single valve is faulty or not.

The invention discloses a hydraulic pump and hydraulic motor reliability testing device based on a power recovery technology. A first shaft extension of a double-extension-bar motor of the testing device is connected with a first hydraulic pump through a first torque tachometer, and a second shaft extension of the double-extension-bar motor is connected with a second hydraulic motor; the second torque tachometer is connected with a first hydraulic motor and a second hydraulic pump, a pressure oil mouth of the first hydraulic pump is connected with an oil inlet of the first hydraulic motor, and a pressure oil mouth of the second hydraulic pump is connected with two hydraulic oil pipelines; the first hydraulic oil pipeline is connected with an electromagnetic spill valve and a remote pressure regulating valve and connected with an oil tank through a flowmeter, and the second hydraulic oil pipeline is connected with an oil inlet of the second hydraulic motor. By establishing the samples of the two tested hydraulic pumps and the samples of the two tested hydraulic motors through the double-extension-bar motor, energy is saved while testing efficiency is greatly improved; the hydraulic pump and hydraulic motor reliability testing device based on the power recovery technology further has the advantages of simple operation and easy popularization.