Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B17/00—Pumps characterised by combination with, or adaptation to, specific driving engines or motors
  • F04B17/03—Pumps characterised by combination with, or adaptation to, specific driving engines or motors driven by electric motors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
  • F04B49/06—Control using electricity
  • F04B49/065—Control using electricity and making use of computers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B23/00—Pumping installations or systems
  • F04B23/04—Combinations of two or more pumps
  • F04B23/06—Combinations of two or more pumps the pumps being all of reciprocating positive-displacement type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
  • F04B49/08—Regulating by delivery pressure
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B19/00—Program-control systems
  • G05B19/02—Program-control systems electric
  • G05B19/04—Program control other than numerical control, i.e. in sequence controllers or logic controllers
  • G05B19/042—Program control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
  • G05B19/0426—Programming the control sequence

Definitions

• An electronic controlled rotary fluid device improves robustness of the device identified in U.S. Patent Publication Number 2010/0021313 for systems in which the variation in performance due to external factors such as fluid temperature is to be reduced.
• Certain examples of the disclosure can include systems and methods for controlling a rotary fluid device.
• a control methodology can be applied to single motor-pump configurations and multiple motor-pump
• the single and multiple motor-pump configurations may only require a single pressure sensor for an entire power pack system.
• the single pressure sensor can be integrated into a control loop to periodically provide pressure data used to reduce variation in the performance of the system. Accordingly, the sensed pressure data may initiate an updating step causing a recalculation to the parameters used to control the fluid device system.
• control methodology can be implemented by a controll er that allows for the system to further refine current commands sent to a motor by using a dynamic current command update.
• the dynamic current command update can be applied to maintain steady state operation, when a flow demand or system pressure may cause the fluid device system to operate in a transient state.
• the periodic sampling of the pressure sensor of system can be used to determine if an update to the operating parameters should be made. For example, when the desired system pressure and the sensed system pressure exceed a predetermmed threshold, the operating parameters may be updated to minimize the difference between the current and desired system pressure. In the proceeding system operations, updates may serve as the system parameters.
• the control methodology also possesses fail safe mechanisms, wherein when certain operating parameters exceed predetermined thresholds the system may revert back to initial factory settings.
• the controller uses updated operating parameters to perform control operations on multi-motor pump systems.
• the eoniroiier can maintain and updaie a lookup table for each motor-pump configuration in the system.
• the controller can recalibrate the lookup table for each configuration.
• the controller can also be configured to determine the operation of the pressure sensor by comparing the operation of the sensor by alternating the active motor-pump configuration.
• the controller can be configured to statistically differentiate the current operation from the initial operation of the system using the system operating parameters to determine the useful life of system components.
• the controller can operate the system in a power savings mode, wherein various configurations and alternating activity of multi- motor-pumps can be used to maximize the useful life of the motor-pumps, while maintaining a requested system flow output and pressure.
• the power saving mode may be applied in controller examples where the controller is configured with sub-controllers that control an individual motor-pump and communicate with each other.
• FIG. 1 is a schematic vie of a hydraulic system having a rotary fluid device and control methodology according to an example of the disclosure.
• FIG. 2 is a schematic view of a hydraulic system having a rotary fluid device and control methodology according to another example of the disclosure.
• FIG. 3 is a schematic view of a hydraulic system having a rotary fluid device and control methodology according to another example of the discl osure utilizing a dynamic current command adjustment.
• FIG. 4 is a block diagram illustrating a dynamic current command adjustment.
• FIG. 5 is a block diagram illustrating a motor drive controller command.
• FIG. 6 is a lookup table according to an example of the disclosure.
• FIG. 7 is a chart illustrating health trending of a rotary fluid device
• FIG. 8 is a block diagram for illustrating an example method for controlling a fluid system with a plurality of pumps according to an example of the disclosure.
• FIG. 9 is a flowchart for illustrating an example method recalibrating the modifiable lookup table for a fluid pump according to an example of the disclosure.
• FIG. 10 is a flowchart for illustrating an example method for determining the fluid pump operation in a plurality of pumps and pressure sensor operation according to an example of the disclosure.
• An aspect of the present disclosure relates to a fluid system that has a fluid pump having an output, an electric motor that operates the fluid pump in response to an electrical signal, a pressure sensor, and a controller.
• the controller communicates the electrical signal derived from a modifiable lookup table.
• the pressure sensor communicates with the controller and the controller updates the modifiable lookup table based on a difference between the desired system pressure and the sensed system pressm'e to minimize variation between the sensed system pressm'e and the desired system pressure.
• the fluid system also including a temperature sensor for sensing a hydraulic fluid temperature of hydraulic fluid passing through the fluid pump.
• the controller also includes a plurality of initial lookup tables and plurality of modifiable lookup tables corresponding to different hydraulic fluid temperatures. Based on the hydraulic fluid temperature sensed by the temperature sensor, the controller selects an appropriate modifiable lookup table from the plurality of updatable lookup tables.
• controller in the fluid system being configured to monitor the sensed motor speed over time and determine whether an acceleration condition exists.
• the controller is also configured to modify the electrical signal sent to power the motor when the acceleration condition exits.
• the recalibration steps may comprise receiving sensed performance data from a sensor; retrieving initial performance daia related to the fluid pump and the electric motor from a memory module; storing the sensed performance data and the initial performance data in a modified lookup table; in response to a sensed measurement from the pressure sensor, comparing the sensed performance data and the initial performance data to determine a correlation between the sensed perform;! nee data, the initial performance data and the desired system pressure; generating an updated version of the modifiable lookup table; using the updated version of the modifiable lookup table to send a motor current command signal to the controller.
• Another aspect of the present disclosure relates to a fluid system that has a plurality of fluid pumps, each pump coupled to a motor.
• the fluid system includes a junction location for combining fluid outpui flow from the fluid pumps, and wherein a pressure sensor is positio ned at or downstream of the junction location.
• each motor is controlled by a sub-controller.
• the steps to determine pressure sensor functionality may comprise sensing a first pressure measurement while first individual pump in the plurality of pumps produces an output flow and the remainder pumps in the plurality of pumps do not produce a flow output; determining whether the first pressure measurement is an anomaly based on a predetermined threshold for system pressure; in response to de ermining that the first pressure measurement is an anomaly, sensing a second pressure measurement wherein the second pressure measurement is based on alternating the first individual pump to a no flow output state and producing the flow output from a second individual pump from the remainder pumps; and determining whether the second pressure measurement is an anomaly based on the predetermined threshold for system pressure.
• FIG. 1 illustrates a hydraulic system having a rotary fluid device and a methodolog for control of a rotary fluid device system 100, such as a motor 104 and pump 102, in which the indirect pressure control using motor current and lookup tables is supplemented using a pressure sensor 108.
• the rotary fluid device described herein is a positive displacement pump 102 (e.g., inline piston, radial piston, gear, etc.) that is driven by a variable speed electric motor 104.
• a low pressure side of the pump 102 can be in fluid communication with a reservoir 136.
• a current sensor 1 12 used for a lookup table 1 16 based control can be installed anywhere that steady state current can be detected including on the input cables of the motor drive (e.g., 3Phase 400Hz 1 15 VAC), after the transformer and rectification in a controller 106 (135
• the controller receives a motor phase current 134 from the current sensor 1 12,
• the controller 106 further includes a plurality of outputs including a voltage output, a phase current output, and a phase angle output.
• each of ihe plurality of outputs is in electrical communication with the electric motor 104.
• the controller 106 further includes a circuit having a microprocessor and a storage media, in an example, the microprocessor may be a field programmable gate array (FPGA).
• the FPGA is a semiconductor device having programmable logic components, such as logic gates (e.g., AND, OR, NOT, XOR, etc.) or more complex combinational functions (e.g., decoders, mathematical functions, etc.), and programmable interconnects, which allow the logic blocks to be interconnected.
• the FPGA can be programmed to provide voltage and current to the electric motor 104 of the rotary fluid device system 100 such that the rotary fluid device system 100 responds in accordance with desired performance characteristics (e.g., constant horsepower, pressure compensation, constant speed, constant pressure, etc.).
• the storage media can be volatile memory (e.g., RAM), non-volatile memory (e.g., ROM, flash memory, etc.), or a combination of the two.
• the storage media includes program code for the FPGA, an initial lookup table 120 and a modified (dynamic) lookup table 1 16.
• Motor speed command 128 is based on a modifiable lookup table 1 16, which consolidates the pump and motor characteristics (e.g., torsional, volumetric, and electrical efficiency ) into a single curve of steady state motor speed versus current that results in the desired pressure 132. versus flow at the output of the pump 102.
• This approach may be modified to use a family of curves for external factors, which may have a strong influence on the motor-pump performance.
• Fluid temperature 138 is an example of one such variable illustrated in FIG. 1 .
• a temperature transducer 1 10 installed in a flow stream of the pump 102 can be used to adjust the speed versus current curve to ensure a more consistent output pressure from the system 100.
• the control methodology adjusts the motor-pump steady state operating characteristics, which can be considered a slow control loop thai adjusts the pump performance at a very slow rate (e.g., less than about 1 Hz).
• a pressure sensor 108 between the pump outlet port 102 and the hydraulic consumers 124, the pump control lookup table 120 can be modified in order to minimize the variation in the outlet pressure, A pressure sensed 130 by the sensor 108 is compared with a desired set pressure 132 (e.g., 3000 psi) and the difference is added as an error signal to adjust the speed versus current modified lookup table 1 16 (possibly as an outer proportional- integral- derivative (PID) control, although other control schemes are possible).
• PID proportional- integral- derivative
• the fluid device system can include a dynamic current adjustment.
• the dynamic current adjustment 302 is a control element that can be used to further adjust the current command when the sy stems respond to conditions that may cause the system to operate in a transient state.
• the dynamic current adjustment 302 can use the inputs of the motor current command 204 and the measured motor speed 202 to generate and an updated motor current command 304.
• the output from the modified table 1 16 is a motor current command 204, which is sent to the controller 106 that may adjust the speed of the motor 104 in order to maintain the desired attribute of the system 300, depicted in FIG. 3, As discussed earlier, the dynamic current adjustment is completed in element 302 as depicted in FIG. 4.
• the motor 104 may respond by accelerating into a transient state.
• the dynamic current command adjustment 302 may further modify the motor current command 204 generated from a recalibration routine 1 18.
• the motor current command 204 and measured motor speed 202 serve as inputs.
• the controller 106 may calculate a motor acceleration 402 and determine whether the calculated acceleration exceeds a predetermined threshold. Based on the calculated acceleration, a control gain 404 may be applied to generate a command adjustment 406.
• the command adjustment 406 may be an output of a proportional derivative integral
• the adjustment factor may be an output of a function generated from various combinations of proportional, derivative, and integral controller functions.
• the dynamic current command adjustment routine 302 may then perform a function operation at a summing point 408 to combine the command adjustment 406 with the motor current command 204 to produce an updated motor current command 304.
• the controller takes the feedback from the system operation to determine the electrical power 1 14 sent to a motor 104.
• the controller 106 takes the motor current command 2.04 and the measured motor current 510, sensed from a current sensor 508 and determines the difference between the two inputs at a summation point 502.
• the error indicates the difference between current supplied to power the motor and the current that the system requires to maintain a desired attribute.
• the error signal resultant from the summation point can be minimized.
• the controller 106 may apply a PID controlling function 504 to the error signal to generate a motor control signal.
• the motor control signal may be an output of a. function generated from v rious combinations of proportional, derivative and integral controller functions.
• input electrical power 126 is combined with aspects of the generated motor control signal that may include adjustments to: current, frequency, voltage, or phase angle.
• the resulting output can be the motor power 14 sent to power the motor.
• the updated motor command 304 may be used as an input to the controller 106, instead of the motor current command 204,
• FIG. 6 illustrates an exemplary modified lookup table data 600 to be stored in a memory device, such as re-writable memory, and used for the motor control.
• the initial lookup table 120 is stored in read-only-memory (ROM) and is used for health monitoring and reversion as described later in this disclosure.
• ROM read-only-memory
• the pressure sensor 108 is being used only to adjust the modified lookup table 1 16 within the motor controls and is not within the speed control loop, a low frequency (e.g., ⁇ lHz) loop rate can be used.
• direct communication between the pressure sensor 108 and the controller 106 is not required to prevent latency. Instead, for configurations where the mo ior controller (drive) 106 is remote from the motor 104 and pump 102, the pressure sensor 108 signal can be discretized and
• a least squares error 608 for each operating point 606 as compared to the factory set lookup table curves 602 can be used to measure the change in motor-pump performance over time. For instance, as mechanical wear-out of the pump 102 occurs, the pump internal leakage and internal friction may increase causing a drift in the motor current required to maintain the pump pressure at the set point 606. This drift can be measured using a least squares calculation of the error 608 between the adjusted operating condition to maintain steady state 604 and initial curves 602 programmed into read-only memory when the motor-pump was assembled at the factory. For example, the value of the least squares error 608 can be plotted over time, as shown in FIG. 7. By trending this over time, the health of the motor 104 and pump 102 can be determined in addition to trending the degradation in pump performance to predict the onset of failure before it occurs (predictive health monitoring 122).
• Curve 712B illustrates a sudden shift in motor-pump performance, which may be the result of a total pump failure or loss of the pressure sensor.
• Curve 712D illustrates a gradual drift, which would make the motor-pump appear to be more efficient. This would likely indicate calibration drift in the pressure sensor (108) or temperature sensor 1 10.
• a lower threshold 704 may be used to indicate required replacement of the motor- pump assembly or testing of the sensors.
• Any detected faults or prediction of faults to occur will be communicated outside of the control system through an appropriate interface, such as an aircraft user interface. These communications can be used by a system controller or maintenance computer to direct action (e.g., maintenance activity or reconfiguration of ihe aircraft system).
• the motor-pump control described herein is robust as described above and fail safe.
• pressure sensor failure e.g., detectable by a time history similar to curve 712B but differentiated from normal transient flow response by persistence greater than about 0.5 seconds for instance
• the motor 104 and pump 102 will continue operating with the data table as constructed just prior to loss of the signal If the error is too great (exceeds a pre -determined threshold 702), the motor 104 and pump 102 will revert to the initial lookup table coded in read-only memory at the factory. In this condition the motor 104 and pump 102 would operate at a lower operating pressure, but would still be available to power the hydraulic consumers 124.
• the pressure sensor 108 will continue to update the lookup table 116 to control the motor-pump device to the set pressure. If performance of the motor 104 and pump 102 degrades to a point where the steady state current exceeds the limit allowed by the electrical power distribution system, the motor-pump control 106 can be set to reduce the set pressure to continue operation. Trending, as described above, can be used to determine the maximum duration of safe operation within an operating threshold based on the maximum current allowed and the minimum pressure required.
• FIG. 8 an example is described in which additional controls may be added to a hydraulic power pack system 800 that includes at least two motors (802, 806) and two pumps (804, 808) providing hydraulic flow. Each pump is in fluid communication with a fluid reservoir (812, 813).
• the configuration illustrated obviates multiple pressure sensors in each power pack system 800.
• the example illustrated in FIG. 1 uses one pressure sensor 108 per motor 104 and pump ( 102)
• the example in FIG, 8 uses only one pressure sensor 814 per power pack system 800.
• the illustrated pressure sensor 814 has been placed on the down-stream side of the output filter 816.
• pressure sensors 814 may be installed before the filter 816 or in systems in which no pressure filter 816 is installed.
• a controller 810 can be configured to operate multiple sub-controllers.
• sub-controller 1 (818) and sub-controller 2 (820) may each individually operate a respective motor-pump configuration.
• sub-controller 1 (818) controls the operation of motor 1 (802) and pump 1 (804).
• sub-controller 2 (820) controls operation of motor 2 (806) and pump 2 (808).
• these controllers may be installed in a single enclosure as illustrated schematically.
• adjustment to a modifiable lookup table 1 16 can also be impacted based on the temperature of the hydraulic fluid in the pumps received from the temperature sensors (830, 832).
• the power packs can be individually powered and calibrated (e.g., only one motor-pump is powered at a time) using the common pressure sensor 814 illustrated in FIG.8 after the power pack output filter 816.
• the remaining pumps can be commanded to operate at reduced pressure (e.g., 1500 psi).
• reduced pressure e.g. 1500 psi
• the pump(s) set to operate at lower pressure will have their output flow blocked by the outlet check valve (822, 824) and will not contribute to the system flow.
• the pump operating at full pressure may be calibrated using the methodology described above in reference to FIGS. 1-7 to adjust the speed versus measured current lookup table 1 16 to maintain system pressure.
• the remaining pumps can then be sequenced individually to full pressure (while all others are set to low pressure) using the single pressure sensor 814 to calibrate the modifiable lookup table 1 16.
• This method can be used for calibration any time the power-pack system 800 is operational and the calibration mode can be aborted immediately if a system flow demand is detected by reduced power pack output pressure in combination with the full pressure pump operating at or near its maximum speed or above a predetermined threshold (25% speed for instance).
• Health monitoring 826 and prognostics described above may also be used to monitor the performance of the individual motor-pumps over time.
• the alternate pump will maintain the required system pressure (e.g., 3000 psi) and hold the reduced pressure pump check valve closed. If a high flow demand is detected by a low pressure in combination with the primary pump reaching maximum speed or a speed above a predetermined threshold (e.g., 90% speed), the lower pressure pump will immediately exit power savings mode and provide supplemental flow to the system at the rated system pressure (e.g., 3000 psi).
• a predetermined threshold e.g. 90% speed
• a communication link between the motor-pump sub-controllers (818, 820) may be used to hack the motor-pump usage (e.g., time at torque/speed for the individual motors) and balance the power savings mode between the two units.
• One such method is to always opt to operate the motor-pump with the highest damage ratio (calculated as integral of input electrical power over the operating time) in power savings mode. This will balance the wear and tear between the two motor-pumps (802, 804, 806, 808) and maximize system life.
• a communication linkage between sub-controller 1 (818) and sub controller 2 (820) may also be used to prevent the individual motor-pumps from operating at maximum speed (or minimize the time operating at or near maximum speed) by balancing the loads between the two motors (802, 806). For example, if a large hydraulic consumer 828 flow is demanded, the typical control will cause one motor- pump to ramp-up to near full speed while the other, potentially in a lower pressure power savings mode, will continue to operate at a near zero speed.
• a system monitoring and control function may be used to command the two pumps (804, 808) to equal speeds, whereby each pump will output half of the system flow demand by operating at one-half its rated speed.
• a speed threshold may be used on the primary pump to determine when the second pump should be powered to supplement the system flow. For example, the second motor-pump may be commanded out of low pressure power savings mode if the primary motor-pump speed exceeds 25% of its rated value.
• temperature sensors (830, 832) on the motor-pumps can be used by a monitoring and control function to adjust which motor-pump is providing system flow based on the individual motor temperatures. This can potentially be used to permit safe operation of the pow er pack if the usage, duty cycle, or failure of one of the motor-pumps causes one of the motor-pumps to overheat. In this case, the overheating motor-pump will be commanded into a lower power state (or off depending on the severity of the overheat condition) and the other (in a dual motor- pump arrangement) will be commanded into full pressure mode.
• FIG. 9 is a flowchart for illustrating an example method for recalibrating 1 18 a modifiable lookup 1 16 table according to an example of the disclosure.
• the method 900 can be implemented by systems 200 in FIG. 2.
• the operations described and shown in the method 900 of FIG. 9 may be carried out or performed in any suitable order as desired in v arious examples of the disclosure. Additionally, in certain examples, at least a portion of the operations may be carried out in parallel.
• the method 900 can start in Block 905; the method can include receiving sensed performance data from a sensor.
• the method can include retrieving initial performance data related to the fluid pump and the electric motor from a memory module.
• the method can include storing the sensed performance data and the initial performance data in a modified lookup table.
• the method can include in response to a sensed measurement from the pressure sensor, comparing the sensed performance data and the initial performance data to determine a correlation between the sensed performance data, the initial performance data and the desired system pressure.
• the method can include generating an updated version of the modifiable lookup table. In certain examples, the update to the modified lookup table will only occur when deviations between the desired and the sensed pressure exceed a predetermined threshold.
• the method can include using the updated version of the modifiable lookup table to send a motor current command signal to the controller.
• FIG. 10 is a flowchart for illustrating an example method for determining an operating functionality of the pressure sensor.
• the method 1000 can be implemented using a multi pump system, such as 800 in FIG. 8.
• the operations described and shown in the method 1000 of FIG. 10 may be arned out or performed in any suitable order as desired in various examples of the disclosure.
• the method can start in Block 1005, the method can include sensing a first pressure measurement while a first individual pump in the plurality of pumps produces flow output and the remainder pumps in the plurality of pumps have no flow output.
• the first individual pump can be the only pump that is powered to produce flow for the system, while the remaining pumps in the sy stem are unpowered.
• the first individual pump can operate at the desired pressure of the system and the remaining pumps in this system are powered but operated a lower pressure such that the flow from the remaining pumps is inhibited by cheek valves.
• Block 1005 is followed by Decision Block 1010.
• a determination is made whether the first system pressure from ihe pressure sensor is an anomaly.
• An anomaly can be a predefined variation fro a threshold, if it is determined that the first pressure measurement is an anomaly, then the YES branch is followed and the method 1000 continues to Block 1020.
• Method 1000 proceeds to Decision Block 1025 from Block 1020 and a determination is made whether the second pressure measurement is an anomaly. If it is determined that the second sensed pressure is an anomaly, then the YES branch is followed and the method continues to block 1035. At Block 1035, a responsive action may be required to address the pressure sensor. Referring back to Decision Block 1025, if it is determined ihai the second pressure measurement is not an anomaly, then the NO branch is followed and the method 1000 continues to Block 1030 where a responsive action may be required for the first pump.
• method 1000 can be applied to a fluid device system where there are more than two pumps, where active pump operational status can be rotated through each pump in the plurality to determine the operational efficiency of each pump, as well as determine the operation of the pressure sensor.
• blocks of the block diagrams and flow diagrams support combinations of means for performing the specified functions, combinations of elements or steps for performing the specified functions and program instruction means for performing the specified functions. It will also be understood that each block of the block diagrams and flow diagrams, and combinations of blocks in the block diagrams and flow diagrams, can be implemented by special purpose, hardware- based computer systems that perform the specified functions, elements or steps, or combinations of special purpose hardware and computer instructions.

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• Computer Hardware Design (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Automation & Control Theory (AREA)
• Control Of Positive-Displacement Pumps (AREA)

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• 2014
  • 2014-10-29 EP EP14799282.0A patent/EP3063410A1/de not_active Withdrawn
  • 2014-10-29 US US15/033,324 patent/US20160265520A1/en not_active Abandoned
  • 2014-10-29 WO PCT/US2014/062973 patent/WO2015066219A1/en not_active Ceased

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