Abstract: A controller for controlling operating parameters associated with fluid flow, speed or pressure for a centrifugal pump for pumping fluid, wherein at least one sensor is coupled to the pump for generating a signal indicative of a sensed operating condition. The controller comprises a storage device for storing data indicative of at least one operating condition and a processor in communication with the sensor and operative to perform an algorithm utilizing the at least one sensor signal and the stored data indicative of the at least one operating condition to generate a control signal, wherein the control signal includes a correction factor between 0.1 and 1.0 that is applied to the pump controlling algorithm in order to prevent overcorrection.

Abstract: A compressor diagnostic system incorporates a control which receives a plurality of data streams about various operational features of the compressor. As an example, both temperature and pressure of the suction and discharge refrigerant are taken and sent to the control. Moreover, information with regard to the power being supplied to the motor is taken and stored. All of this information is utilized at a control which compares the information to expected values and determines a fault based upon the evaluation. Moreover, in another feature of this invention, much of this data is stored, and maintained at the compressor. In the event of a compressor failure, this stored information will provide a maintenance worker with a good indication of why the compressor failed.

Abstract: A liquid pump system for providing liquid to a tank includes a variable-speed motor drive and a control circuit coupling the variable-speed motor drive to a power source. The control circuit has a switch that may be disposed in a state according to the amount of liquid in the tank. The control circuit provides for supplying power to the variable-speed motor drive from the power source regardless of the state of the switch. The control circuit may include a transmitter that generates a high frequency signal representative of the state of the switch. In that embodiment, a detector coupled to the variable-speed motor drive receives the high frequency signal to control operation of the liquid pump system.

Abstract: A method is presented to prevent compressor damage by reducing compressor load when operating speed either is too low or too high as can be the case at extremes of line frequency and voltage. The speed of the compressor is deduced from the knowledge of compressor load, frequency and voltage. If the compressor speed is too high or too low for a given suction and discharge pressure, the compressor load is reduced to boost the operating speed or to reduce force acting on the bearings. The compressor load reduction may be achieved by actuating an unloader valve, a suction throttling device, or some other load reduction mechanism.

Abstract: A method of operating a radial compressor wherein the output pressure and the throughput {dot over (m)} through a radial compressor are measured and the working point A in the operational characteristic diagram of the compressor is determined. For predetermined settings of the discharge flow control, the pump limits of the intake flow control characteristic fields are calculated in the operational characteristic diagram of the compressor. When the discharge flow control is so set that the working point falls in a working range associated with one of the pump limits and whose boundaries in the compressor operational characteristic diagram is spaced by a predetermined minimum spacing and a predetermined maximum spacing from the pump limit. When the working point A varies within this working range, only the intake flow control is adjusted. When the working point leaves the range, the discharge flow control is also adjusted.

Abstract: A multistage vacuum pump unit having a plurality of separate single-stage pumps connected in series with each other by exhaust pipes, the exhaust pipes each connecting a suction port of one of the adjacent single-stage pumps with an exhaust port of another of the adjacent single-stage pump; motors for driving the separate single-stage pumps respectively; driving device for varying a revolution of one of the single-stage pumps that is at least in contact with an atmospheric side; driving current detection device for detecting a driving current of the motor for driving the single-stage pump that is in contact with the atmospheric side; pressure detection device for detecting a pressure at a vacuum-side inlet; and control device for controlling revolutions of the motors of the single-stage pumps based on the pressure detected by the pressure detection device.

Abstract: A system is provided for proceeding with automated filtration of liquids in a manner which allows for quantitative collection of desired filtrates or permeates. The system, as well as its associated method, monitors various parameters which are fed to a processor-controlled pump unit. This pump unit has several alternative modes of operation, including controlling the rate of flow through the pump unit. Data are received from one or more pressure sensors and preferably also from a scale. The processor-controlled pump unit operates on these data to control flow velocity and/or filter back pressure within the system.

Abstract: An automatic sub-floor pumping system, having a controller box, sensor wires, suction hose and pump. Two or three sensor probes are used--the lowest, or ground, probe can be omitted, and the circuit referenced to earth or wiring ground. The pump evacuates water from beneath the basement floor through a hose inserted into a small hole drilled into the basement floor. The sensor probes can be simply wires with the last 1/8" to 1/2" bared, attached to the outside of the pump suction hose at two locations an inch or two apart. The hose, with wires attached, is inserted down the one-inch evacuation hole bored through the floor. The control uses a very low current on the wires, which are negative relative to ground so as to be cathodically protected from corrosion. An optional sensing circuit monitors lower probe wire voltage and warns of possible corrosion effects.

Abstract: An infusion apparatus includes a pump powered by a source of battery power and capable of operating in a plurality of infusion modes and operating in a power savings mode. The infusion apparatus further includes sensors which sense various conditions of the pump. A controller is programmed to periodically operate in a power-savings mode of operation and also selectively causes each sensor to be connected to the battery power only when the sensor is to detect a condition, thus further conserving battery power.

Abstract: Balancing the load between compressors is not trivial. An approach is disclosed to balance loads for compression systems which have the characteristic that the surge parameters, S, change in the same direction with rotational speed during the balancing process. Load balancing control involves equalizing the pressure ratio, rotational speed, or power (or functions of these) when the compressors are operating far from surge. Then, as surge is approached, all compressors are controlled, such that they arrive at their surge control lines simultaneously.

Abstract: A method of controlling the operation of a centrifugal compressor in a water chiller system. The compressor's capacity is variable by modulating its speed of rotation or by modulating its inlet guide vane's position. The water chiller includes an evaporator having a leaving water temperature. The method comprises the steps of: monitoring the leaving water temperature; determining if the leaving water temperature is in a steady state; modulating the compressor capacity by modulating speed of rotation if the leaving water temperature is in a steady state; and modulating the compressor capacity by modulating inlet guide vane position if the leaving water temperature is not in a steady state.

Abstract: A hydraulic pressure booster device suited for increasing in-line fluid pressures comprises the assembly of a vertically oriented, tubular, closed end, housing for a submersible fluid pump. The pump is secured to a cap flange which closes the top of the tubular housing, while the bottom of the tubular housing is closed with either an anchor plate or blind end cap. Compression seal fittings are used to seal the penetration of pump motor pump lead wires through the cap flange. Inlet flow received into the tubular housing is drawn through the submersible pump with a resultant increase in hydraulic pressure at the output. A housing pressure sensing switch interrupts pump operation to prevent pump damage during periods of low fluid level in the housing. Additional pump protection is provided via a pump outlet pressure monitoring switch which regulates the pump delivery pressure. Dimensional design features of the device enhance useability and maintainability.

Abstract: In a hydraulic drive system for a construction machine, first flow control mechanism includes first and second flow control valves (11a, 11b) and first interlock mechanism (54, 55) for interlocking the first and second flow control valves with first directional control mechanism (7), and second flow control mechanism includes third and fourth flow control valves (12a, 12b) and second interlock mechanism (56, 57) for interlocking the third and fourth flow control valves with second directional control mechanism (9). First pressure control mechanism includes at least first pressure control valve (13a) operated in response to a pressure signal in a valve-closing direction, and second pressure control mechanism includes only second pressure control valve (15b) operated in response to the pressure signal in a valve-closing direction.

Abstract: Transfer by pumping of effluents containing at least one gas phase and at least one liquid phase in a transfer line connecting a source of effluents is optimized by interposing on the line, between the source and the point of designation, a multiphase pump. The rotating speed of the pump is regulated so as to adapt the pump flow rate to at least one of the following parameters: flow rate variation well, variation of the volumetric ratio GLR or pressure drop variations occurring in the line during transfer. The values of the parameters are controlled and adjusted to values comparable with the operation of the pump.

Abstract: A controller for controlling the capacity of a centrifugal chiller compressor. The compressor is driven by an electric motor and has variable inlet guide vanes that control the flow of refrigerant to the compressor. The controller establishes a dimensionless plot of possible points of compressor operation relating the pressure coefficient and the capacity coefficient of the compressor. The current operating point of the centrifugal compressor is located on the plot and a dynamic surge boundary control curve is positioned proximate a region of actual surge. Control is exercised responsive to the variations of the region of actual surge and the surge boundary control curve for controlling compressor capacity by varying the opening of the inlet guide vanes and varying the speed of the compressor to move the operating point of the compressor proximate the surge boundary control curve.

Abstract: The invention is a pressure sensitive valve that in different forms can be used to provide: an adjustable resistance to flow, adjustable positive or negative pressure relief, negative pressure isolation, isolation of pressure sensitive devices (e.g. pressure monitors) from blood and controlled recirculation between the inlet and outlet of pumps, particularly extracorporeal circulation. The construction of the valve is especially advantageous for extracorporeal circuits, the valve is made from one continuous length of tubing, thereby providing a valve that is more reliable, safer, and has fewer parts. A simple, compact and disposable system to adjust, regulate, and indicate negative or positive pressure applied to the valve is so described.

Abstract: A well pump system having a motor-driven pump and a pressure tank for delivering water from a source to a utilization point. A sensing device detects a parameter correlated to the rate of flow into and out of the pressure tank. The parameter is utilized to regulate flow into the tank so as to establish at least approximate equality between flow into and out of the tank.

Abstract: A sewage pumping system includes a container, an inlet for the inflow of liquid and a modality for ascertaining the liquid level in the container. Two or more pumps are provided, each having an inlet communicating with a container and an outlet communicating with the common conduit. A pump controller receives information from the modality for ascertaining the liquid level and is adapted to start and stop individual pumps. A pressure sensing device is located in the conduit for sensing the backpressure against which pumps in operation are pumping, and for generating a second signal corresponding to the sensed backpressure, the signal going to the pump controller. An addressable memory is operatively connected with the pump controller and stores values corresponding to pumping rates vs. backpressure for each of the pumps, along with high and low backpressure values for each pump. On high backpressure the pump controller avoids pumpstarts which will not result in a net increase in the total pumping rate.

Abstract: An apparatus includes a compressor for compressing fluid including a sensor capable of sensing at least one function relative to the operation of the compressor. A controller controls the compressor causing the value of said one function to be within a predetermined parameter. A computer overrides the independent response of the controller wherein the controller acts in response to the computer, the computer being separate from said controller. The computer may act as a sequencing computer or as a test computer.

Abstract: A differential pressure sensor indicating a housing forming a high pressure chamber, a nozzle mounted on the housing at one end of the chamber, a diaphragm mounted in the chamber to form a low pressure chamber in the nozzle, a spring retainer in the high pressure chamber, a spindle connected to the diaphragm, a tension spring connecting the spindle to the spring retainer, a circular magnet mounted on the spindle and a transducer mounted on the housing to sense the position of the magnet.

Abstract: A method of controlling the air output of a screw compressor, wherein the average air output of the compressor during operation is adapted to air consumption by throttling the flow of suction air or by connecting the compressor alternately to full air output capacity and idle operation capacity. In order to reduce the power consumption of the compressor, the air output is controlled first by throttling the flow of suction air and by simultaneously measuring underpressure in the suction conduit of the compressor. Thereafter the compressor is controlled so as to operate alternately at full air output capacity and idle operation capacity, and the pressure rise rate in the air-pressure network is measured when the compressor operates at full output capacity and the pressure fall rate is measured when the compressor operates at idle operation capacity.

Abstract: Wire-to-water efficiency (W) of a multi-pump system is monitored and accurately determined according to the formula: ##EQU1## wherein Q is flow through the system, HS is total dynamic head across the inlet and outlet headers of the system, E is energy input to the system to drive the pump, and K is a predetermined conversion factor. The resulting efficiency determination is provided to an operator so that the pump system may be monitored.

Abstract: An automatic pump protection system is comprised of a plurality of sensors for measuring process parameters indicative of a loss of pump suction or of pump motor failure. Analysis of the parameters is performed by a microprocessor in order to determine whether conditions leading to a loss of pump suction or pump motor failure are present. The microprocessor then automatically initiates pump protective action in response to the foregoing analysis by tripping the pump or by providing an alternate suction source.

Abstract: A control system of pumping operation comprises a cycloconverter for converting AC power from a AC power system into AC power having a given frequency, anAC exciting generator-motor, having a stator side electrically connected to the AC power system, having a rotor side electrically connected to the cycloconverter, and having a rotor shaft mechanically coupled to a pump-turbine by which the pumping operation is carried out, a circuit breaker inserted between the AC power system and the AC exciting generator-motor, a rotation speed controller for controlling a rotation speed of the AC exciting generator-motor such that the rotation speed becomes slow when the pumping operation is to be stopped, an AC excitation controller for decreasing a degree of excitation effected by the cycloconverter, wherein decreasing of the excitation degree starts when the rotation speed of the AC exciting generator-motor reaches a given minimum value, and a circuit breaker controller for turning off the circuit breaker when input po

Abstract: A supervisory computer for a centrifugal compressor control system is disclosed which manipulates the set point of a controller for a valve in a recycle line from the compressor systems outlet to inlet. The supervisory computer manipulates the set point so as to both prevent surging and substantially minimize the recycling of compressed gas. The computer first determines the surge flow limit for the compressor based on prestored data from the compressors manufacture performance curves such as constant speed compressor curves, and the actual speed of the compressor. The controller then outputs a set point signal which periodically moves the control valve in incremental amounts toward the fully closed position. The periodic movement towards the closed position continues until the flow is close to the surge flow limit, or until the actual deviation of the setpoint flow and the actual process flow exceeds a desired high limit for this deviation.

Abstract: A method and apparatus for monitoring and controlling a multi-pump system is described wherein wire-to-water efficiency (W) is accurately determined according to the formulaW=(Q.times.HS/K.times.E)wherein Q is flow through the system, HS is total dynamic head across the inlet and outlet headers of the system, E is energy input to the system to drive the pump, and K is a predetermined conversion factor. The pumps of the system are selectively energized and deenergized as the efficiency W varies above and/or below efficiency setpoints so as to optimize the efficiency of the pumping system.

Abstract: A packaged hydro-pneumatic pumpset system in which a plurality of pumps JI, M2, M3 are brought into operation sequentially as water pressure in the system drops below pre-set values. The system includes an accumulator 6 for storing water to maintain pressure in the system when the pumps are not operating and a prime is maintained on the pumps by means of a footvalve in the suction pipe inlet. The system also includes a second accumulator 9, which is connected to the first and which is arranged, when the pumps are inoperative, to maintain a reservoir of stored pressurized water in the suction manifold.

Abstract: A redundant, pneumatic driver for a blood pump in which a pair of pistons are contained in a common cylinder and their stroke rates and lengths are selectively controlled by a controller which non-invasively senses the circulatory system requirements of the patient in which the blood pump is implanted. The controller varies the stroke rates and lengths to meet such requirements and further is able to selectively switch driving functions from one piston to the other to provide a redundant driving capability.

Abstract: An integrated control system for both the output and surge protection of a centrifugal compressor in a chilled, water system is provided by biasing the output of a feed forward and cascade centrifugal compressor output control logic module with the output of a coordinating control logic module, which utilized a surge control logic module output to establish the biasing signal.

Abstract: Regulator in a motor driven pump for the regulation of the output pressure according to a predetermined value. An automatically functioning reliable regulation according to a predetermined value in order to impede cavitation and reduce the risk of an interrupted flow of liquid in the pump is provided by means of the invention. This is made possible by means of a double diaphragm (12) via a preferably spring biased transmission means (4, 10) of movement being in connection with a controlling means serving the purpose to control the capacity of the power source of the pump and with a space (27) between the diaphragm elements (12A, 12B) of said double diaphragm (12) being connected with the output pressure (30) from the pump for the actuation of the double diaphragm (12) in order to adjust the controlling means of the capacity in a desired degree, and increased or decreased fluid output from the pump bringing about a displacement of the double diaphragm (12) to its maximum position (FIG.

Abstract: An improved oil pump assembly for a refrigeration compressor is disclosed which includes a sensor located within the oil pump housing which is operative to de-energize the compressor in the event the pressure differential between the inlet and outlet of the oil pump drops below a predetermined level. Pressure sensing communication between the sensor and the inlet is provided via a cutout portion of the gasket between the pump and compressor housing.

Abstract: A control method and a control system for a hydrostatic drive system including a variable displacement hydraulic pump and a hydraulic actuator connected together to form a closed hydraulic fluid circuit. When the flow rate of the hydraulic pump is increased, the rate of change in the tilt of the hydraulic pump is controlled so that the discharge pressure does not exceed a first set of preset values with respect to the flow rate of the pump, meanwhile when the flow rate of the pump is reduced, the rate of change in the tilt of the hydraulic pump is controlled so that the suction pressure does not exceed a second set of preset values with respect to the flow rate of the pump.

Abstract: A control system for a compressor utilized in transferring natural gas from relatively low pressure wells to a relatively high pressure pipe line incorporating automatic shutdown of the compressor and automatic restart of the compressor in response to certain conditions with the compressor operating at a desired flow rate regardless of upstream fluctuations in pressure. The compressor is unloaded upon shutdown and remains unloaded for a timed duration after startup thereby reducing the required motor size, compressor wear and also eliminating manual startup for most of the usual causes of gas compressor shutdown, such as low well pressure and high discharge line pressure.

Abstract: An oil cooled compressor including a compressor member driven by a motor, an oil tank receiving oil therein and removing oil from the gas discharging out of the compressor member, an oil supplying device for supplying the oil in the oil tank into the compressor member, and a pressure responsive control device for controlling the operation of the compressor member. There are provided a first temperature detector detecting the temperature of the oil, a second temperature detector detecting the temperature of the gas, and a temperature responsive control device restricting the function of the pressure responsive control device in response to the temperatures detected by the first and second temperature detectors.

Abstract: An automatic speed-control actuator for variable speed pumps. A rotary or near actuator changes the pump speed to prevent unacceptably low pressures on the pump inlet or unacceptably high pressures on the pump outlet; pressure switches at these locations control the actuator to produce maximum flow rates through the pump.

Abstract: A solid state system for controlling a compressor or pump which is driven by a motor, the compressor being loaded or unloaded manually or automatically and proportionally to maintain a selected suction-pressure setpoint and to maintain the load on the drive motor within a motor-current setpoint limit, the system having start-up and shut-down sequences which have timed stages including a delay to permit the building up of oil pressure prior to loading of the compressor and including the automatic loading and unloading of the compressor incident to start-up and shut-down. The control includes monitoring of temperatures and pressures associated with the system and automatic shut-down in response to malfunctions internal to the system, and includes automatic shutdown in response to external malfunctions as selectable options, and further includes separate malfunction indicators with a circuit for providing their operability.

Abstract: A pressure compensated safety control is employed to shut off the compressor at high compression ratios, caused, for example, by reduced air flow over the condenser or other reasons. This is especially useful on both reverse cycle heat pumps and conventional, non-reversible refrigeration and air conditioning systems to protect the compressor. In a preferred embodiment, the compensation is provided by making the control responsive to compressor suction pressure.

Abstract: A compression system is controlled so as to maintain the actual suction pressure as close as possible to a desired suction pressure without exceeding the operational limitations of the compression system. The speed of the compression system is manipulated so as to maintain the actual suction pressure equal to a desired suction pressure if no compression system constraint is encountered. If a compression system constraint is encountered, the compression system speed is manipulated so as to operate against the particular constraint encountered without exceeding that particular constraint.

Abstract: The control system of the invention regulates a centrifugal compressor having inlet guide vanes adjustable as one means for varying the compressor capacity. A variable speed motor is connected to drive the compressor, and provides another means for regulating the compressor capacity. The control system regulates the motor speed alone over one portion of the load variation curve, and regulates the motor speed jointly with the inlet guide vane opening over another portion of the load variation curve, to achieve the most energy-efficient operating condition while avoiding the surge condition. This optimum control path is realized by utilizing a signal which is a measure of the compressor head value. Compressor surge or instability is avoided by deriving a critical Mach number (speed indication) for any given operating condition, as a function of the compressor head and vane position, and preventing the motor speed from going below that Mach number under the specific operating conditions.

Abstract: For a well pump installation, automatic control of the starting and stopping of the pump motor relies upon a simultaneous detection of the suction and delivery heads so that a single switch may perform the functions of both delivery pressure control and dry cutting-off.

Abstract: Apparatus and process for automatically measuring and controlling the instantaneous flow rate of a liquid in a piping system by varying the speed of a centrifugal pump in response to a flow rate signal determined indirectly by sampling two flow-related parameters associated with the pump and pump motor and then converting in an on-line computer the two measurements to the corresponding unique flow rate value by the use of previously determined mathematical relationships stored in the computer. The mathematical relationships are derived from data correlating flow rate with the two flow-related variables, which data is taken with a flow meter and control valve temporarily installed in the piping system during the "shake-down" testing of the piping system. A third flow-related variable is sampled, a pair of flow rate values determined, and an alarm activated in response to the difference between the values to provide the additional feature of pump mechanical performance monitoring.

Abstract: A control system is disclosed for a noninteracting control and protection of a dynamic compressor having rotating vanes.The method consists of a junction of a few control circuits for controlling the performance of a dynamic compressor, for protecting compressor from approaching dangerous zones of operation, and for maintaining a required mass flow rate of a gas through the compressor.An automatic control system based on using the above method is distinguished by its simplicity, great transient and steady state precision and high reliability of surge protection.

Abstract: Apparatus for fluid flow control in a parenteral administration system, utilizing a syringe pump operated by a motor to repetitively fill and empty a syringe cartridge over a plurality of operational cycles of successive fill stroke and pump stroke periods. The apparatus repetitively and sequentially opens and closes a pair of intake and output I.V. tubes communicating with a syringe, the tubes alternating opened and closed states, one tube always being open while the other is closed, by means of a pair of L-shaped pivotal tube pinchers, one pincher controlling each I.V. tube, each pincher being normally spring biased to the tube clamping shut-off state. The tube pinchers are alternately pivoted to a non-clamping, tube-open position by a spring biased, intermittent motion, reciprocating slide bar under the control of a reversible, rotating cam, the cam being driven by the same motor as that used to drive the piston of the syringe through its fill and pump strokes.

Abstract: A method is disclosed for a cascade control of a dynamic compressor to maintain a constant mass flow rate to a process. The method consists of a successive junction of control loops for controlling the speed of rotation, the pressure in the delivery, and the mass flow rate; the output signal of each outer loop being the input signal for the inner loop and each of the loops containing a compensating element to reduce the effects of large time constants of all previous loops.An automatic control system based on using the above method, distinguished by its great static and dynamic precision in maintaining a controlled parameter, and by the high reliability of protection of the compressor from surge, and protection from a dangerous increase of the speed of rotation and of a dangerous increase of the discharge pressure.