Abstract: There is disclosed herein a pump check valve test system embodied in a pump control system which control pump speed based upon actual pressure and upon actual pump speed and desired flow rate. The check valve test system disables the portion of the control system which controls pump speed based upon desired flow rate during the test. The test is comprised of timing the time it takes the pump to rotate through the portion of each cycle wherein the check valve is supposed to close and comparing this time to a known value.

Abstract: A vacuum pump has a housing, a pump shaft having a terminal shaft portion, a bearing member mounted in the housing and supporting the pump shaft and a rotor affixed to the pump shaft. The housing has a housing wall forming a side chamber with the bearing member. The terminal shaft portion projects through the bearing member into the side chamber. There is further provided a device for measuring the rpm of the rotor. The device comprises an inductive sensor held in the housing wall and a ferromagnetic member mounted on the terminal shaft portion for rotation in unison therewith. The ferromagnetic member induces electric pulses in the inductive sensor at a rate proprotionate to the rpm of the rotor. A non-magnetic partition separates the inductive sensor from the side chamber.

Abstract: An extracorporate ventricular support system includes a two bladder pump employing continuous gravity fill to the first bladder, while the second bladder is pneumatically driven to produce a pulsatile blood flow. A processor responds to air flow in the pneumatic drive line to control the pump through an electromagnetic valve supplying pressurized air. The program controls the output of blood volume per stroke to meet a target value.

Abstract: An inner short-term pressure sensitive feedback loop is combined with an outer long-term volumetric delivery feedback loop to supply a substantially constant volumetric flow of mixed fluids to a load. The invention has particular utility in the controlled delivery of solvents for liquid chromatography.

Abstract: A motor-driven compressor used as a compressor or high-pressure gas generator for a refrigerating cycle, in which the output torque of the electric motor for driving the compressor is controlled so as to make the output torque agree with the load torque required for performing compression in any revolutional angular position of the driving main shaft to thereby reduce revolutional torsional vibrations caused by disagreement between the load torque and the output torque.

Abstract: A peristaltic pump controller which provides control of a positive displacement pump as either an uncalibrated or calibrated flowmeter, or a calibrated dispenser. A calibration constant is calculated, after the pump is primed, to determine the amount of volume output produced by an increment of angular rotation of the pump. The constant is determined during a calibration operation where an arbitrary calibration volume is metered. The controller has a low flow and high flow mode where the low flow mode provides a higher resolution for dispensing. The flow mode of operation is determined by the value of the calibration constant and is automatically set when the constant is calculated. During a dispensing operation, the controller will meter fluid to within a predetermined amount of the final volume dependent upon the speed of the pump motor and then dribble in the remaining amount of a batch for precision.

Abstract: A method and apparatus for generating a rate of flow signal which is proportional to the flow rate in a fluid distribution system and which is based on a signal which is proportional to the speed of the fluid circulating device and which makes use of the characteristic curves of a fluid circulating system and fluid delivery device is disclosed. In an air-conditioning system having a variable speed supply fan and a variable speed return fan, a method and apparatus for controlling the capacity of the return fan to closely match that of the supply fan is provided.

Abstract: A vacuum pump aggregate utilizes a microprocessor in conjunction with pressure and temperature sensors and motor control circuits to regulate the pressure by varying the speed of one or more vacuum pumps. Measured temperature and/or pressure values are compared with predetermined values by the microprocessor which in turn adjusts the speed of the motors.

Abstract: In a thrust vector control system of the type in which a solid-propellant s generator powers a turbine-driven pump for driving hydraulic actuators for controlling the direction of thrust, the improvement being a feed back control system in which a variable-area gas valve is disposed inline between the gas generator and the turbine. The turbine speed is fed back to an electronic controller where it is compared with a commanded turbine speed. The controller applies forward-loop compensation to provide a signal that adjusts the area of the gas valve to control the operating pressure of the gas generator to drive the turbine speed to the commanded value.

Abstract: An improved pulsation-free reciprocating volumetric pump is disclosed, which comprises two reciprocating plungers, a cam for driving said plungers, a driving motor connected to said cam, a circuit connected to said driving motor for controlling rotational rate, and another circuit for detecting a pressure of combined volume discharged by the two plungers and for correcting a control signal of said rotation controlling circuit through the detected signal.

Abstract: A microprocessor based control system for establishing the optimum points of motor turn on and turn off for an oscillatory pumping system. The power to the motor is disabled at a point calculated to return the maximum stored mechanical energy to the system after turn-around. The motor is restarted at either a predetermined motor speed which may be different in the up and down stroke directions, or when the speed peaks. Safeguards are also provided under control of the microprocessor for disabling pump operation in the event of pump overtravel, overload or pump off. The control permits dynamic changes to the operating parameters of the pumping system in order to optimize the power required by the motor over a wide range of operating conditions.

Abstract: There is disclosed a microprocessor-controlled peristaltic pump for use in a portable continuous insulin infusion device. The peristaltic pump is configured with a removable cover comprising a part of the pump housing surrounding a pump rotor, and holding a delivery tube between the cover and the rotor. The removable cover combines with a reservoir and the delivery tube to constitute a pre-filled disposable package facilitating installation and removal of the insulin in the device. A microprocessor controls the number of times the rotor turns during a cycle. This operation allows the microprocessor to automatically compensate for different diameter delivery tubes, as well as to allow the physician to vary the on/off time of the pump to administer different dosages.

Abstract: A control system for a compressor unit driven by a clean-burn, turbo-charged, gas-fueled engine which is primarily responsive to the load (torque) and the speed of the engine to adjust certain engine parameters to maintain the operating conditions of the engine within a desirable operating zone which is a compromise or "trade-off" between best fuel economy and permissible exhaust emission levels. A number of "maps" which correlate load (torque) at various speeds with specific fuel consumption and exhaust emissions are derived from available manufacturer's data and are programmed into a central processing unit (CPU).

Abstract: A pump primarily intended for use in a portable ventilator. The pump includes a piston-cylinder arrangement in which the piston is reciprocally moved within the cylinder by rotating a shaft. The shaft is threaded and mounted for rotation within the cylinder at a fixed location along the axis of the cylinder. The piston has an aperture through its center and the shaft extends substantially between the end walls of the cylinder and through the center of the piston. The piston is held against rotation relative to the shaft and cylinder by a collapsible hinge and is attached to the shaft by an arrangement including a ball nut and sealing nut. The piston forms a variable volume, working chamber with one end of the cylinder and in operation, the shaft is selectively rotated to move the piston toward and away from the end wall. This positioning of the shaft within the cylinder reduces the overall size of the pump and specifically adapts it for use in a portable ventilator in which size limitations are critical.

Abstract: A control procedure for governing the incremental step operation of a pump stepping motor (74) employed in conjunction with a parenteral fluid metering device (2) is disclosed. The control procedure enables fluid to be pumped from the metering device (2) in non-pulsatile, essentially continuous fashion by suitably adjusting the stepping motor speed to compensate for the interruption of fluid flow which occurs during the refill phase (P.sub.R) of each pumping cycle (C). Adjustment of the stepping motor speed also compensates for non-linearities otherwise introduced into the fluid flow as a result of the camming mechanism (76,78) utilized to convert rotary stepping motor movement into rectilinear pumping movement.

Abstract: Metering apparatus for controlling the flow of fluid through a fluid infusion system at an operator-designated rate includes a single-use cassette having a syringe-type pump in the flow system. The cassette is removably mounted on actuator apparatus which drives the syringe plunger through alternate fill and pump modes to advance fluid through the system. To provide compensation for the lack of flow in the system during fill strokes, the plunger is advanced at a higher compensation rate for first and second portions of the pump stroke immediately preceding and immediately following each fill stroke, with the pump stroke advancing at the designated rate therebetween. This results in an average flow rate which corresponds to the designated rate. By making the first and second compensations of equal duration, the effect of the fill cycles on the regularity of the average flow rate is minimized.

Abstract: A portable battery powered pump providing constant mass flow of air sample through a particular filter or vapor trap in which the pump drive motor speed is controlled by an amplifier having a reference voltage input and an inverse feedback signal related to sensed motor speed. Compensation for increased resistance to air sample flow is made by a motor current feedback signal applied to the amplifier to cause motor speed to increase with increased flow resistance.

Abstract: A method and apparatus for controlling a resonant piston compressor of the type comprising an electrodynamic linear reciprocating motor adapted to be driven cyclically by an alternating current power source and having at least one piston coupled to and adapted to be driven within a selectively valved working cylinder by the linear reciprocating motor in synchronism with the frequency of the alternating current power source. Enclosed volumes of gas act as resilient gas springs coacting with the piston and with the linear reciprocating motor to form a mechanical resonant system having a resonant frequency substantially centered on the frequency of the alternating current power source. A midstroke porting arrangement is responsive to the position of the resonant piston for selectively communicating a gas spring control valve with said gas springs.

Abstract: A pump for producing a substantially smooth and continuous outflow of liquid at relatively high pressure has two piston assemblies flow connected in series. The first piston assembly includes a pressure piston having a long suction stroke and a relatively short and abrupt expulsion stroke. A valve at the inlet of the pressurization piston allows flow to enter (but not exit), and a valve at the outlet of the pressurization piston allows flow to exit (but not enter). The second piston assembly includes a damper piston which functions as a mechanically driven damper to smooth the outflow from the pressure piston. This smoothing is accomplished by storing of the liquid displaced by the expulsion stroke of the pressure piston and then delivering the stored pressurized liquid to the pump outlet during the suction stroke of the pressure piston.

Abstract: A variable speed centrifugal pump for aircraft fuel systems and the like having the capability of matching fuel flow and pressure to engine requirements throughout a variable flight profile without in-line flow controls and metering devices comprising a unique combination of centrifugal impeller stage and positive displacement pump device which controllingly, drivingly, fluidly couples the impeller to the aircraft engine drive. The positive displacement pump device includes rotating hydraulic displacing input and output members, the latter being driven by the former at a relative speed normally responsive to discharge flow rate of the positive displacement pump device which is controlled to regulate impeller speed for matching pump flow and pressure to engine requirements.

Abstract: A precision-delivery and precision-pressure piston pump is actuated by a cam controlled by a finestep stepping motor. The initial delivery pressure is precisely regulated by fixing the commencement of the delivery stroke at the cam with the aid of the stepping motor, as well as the time required for this delivery. Delivery is also regulated very precisely, for example in a ratio of 1 to 1000 by controlling the delivery stroke with the aid of the stepping motor. The pump is of use in particular in high-pressure liquid-phase chromatography.

Abstract: In a process in which a turbo-expander is utilized to drive a compressor, the pressure of the gas flowing to the turbo-expander is maintained at a desired level by manipulating the speed of the turbo-expander. If the turbo-expander should tend to overspeed, the discharge output of the compressor is recycled to the suction inlet of the compressor to thereby increase the loading on the compressor which will result in a reduced turbine speed. More gas can then be fed through the turbo-expander which will maintain the desired pressure. If the pressure of the gas flowing to the turbo-expander should continue to increase, a bypass valve is utilized to bypass the turbo-expander to thereby maintain a desired pressure of the gas flowing to the turbo-expander.

Abstract: Two series connected fans driving a variable throat venturi are controlled by a single flow control feedback loop yet are decoupled by modifying the common flow control signal by separate but complementary piecewise linear characterizations of the flow characteristics of each fan. Both fans are protected from surging and overcurrent by their own differential pressure and current limiting control loops respectively which automatically assume control when conditions warrant. The venturi is controlled by its own differential pressure control loop which is operated to generate the maximum differential pressure allowed by the flow rate without surging the fans.

Abstract: An improved method and apparatus is provided to control the rate at which fuel is supplied to an engine by a fuel pump. The fuel pump has an output pressure which varies with pump operating speed in accordance with different curves of a series of curves. In order to determine which curve of the series of curves is representative of the manner in which the fuel pump output varies with pump speed at one time, the fuel pump operating speed and output pressure are simultaneously sensed to determine a point on an initial curve. The fuel pump operating speed is subsequently varied in accordance with the initial curve to provide a desired variation in fuel pump output to the engine. The fuel pump operating speed and output pressure are periodically simultaneously sensed to determine if the fuel pump output still varies in accordance with the initial curve or has changed to a second curve of the series of curves.

Abstract: A blood pump system in which a roller pump is provided for pumping blood through a flexible tube. A low voltage D.C. motor is provided having an output shaft. An electrical control circuit is connected to the motor for applying the necessary voltage to drive the motor at a predetermined speed. Gearing means are provided connecting the motor's output shaft to drive the roller pump. Means are optically coupled to the motor for controlling the speed of the motor. Means are connected to the optically coupled means to determine the blood flow rate being pumped through the tube by the pump. Means are provided which display a digital readout of the flow rate. The roller pump is provided with an arcuate bearing surface, which carries the flexible tube, the bearing surface defining an arc of approximately 168.degree.. Lead ramps extend from each end of the bearing surface and are substantially tangent to the end of the surface from which the respective ramp extends.

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: A fluid pump mechanism for delivering a smooth output of fluids to a system utilizing at least one piston in a chamber reciprocative therewithin. The piston has strokes that fill and empty the chamber in conjunction with the action of valve means located at the inlet and outlet of the chamber. Motive means causes reciprocation of the piston within the chamber. Control means is also included for minimizing the time during the piston cycle in which the piston is not emptying the chamber. The invention's scope also encompasses a pressure metering device for a fluid forcing means motivated by an electrical motor.

Abstract: In an axial blower, the noise generated by the blower increases generally in proportion to the increasing number of rotations of the blower's rotor. It has been ascertained, however, that over a given range of rotational speeds, the magnitude of noise plotted in a graph as the function of the rotational speed describes not a smooth curve but a zigzagging curve, indicating that zones of rotational speeds producing high levels of noise and those producing low levels of noise are distributed irregularly.

Abstract: This is a method and apparatus for controlling an oil-well beam pumping unit in a manner which allows increased oil production. The AC electric motor of the beam pumping unit is supplied power through a variable frequency power supply, whose frequency (and voltage) is controlled by circuitry to automatically adjust to whatever flow enters the wellbore by varying the speed of the pumping unit to maintain the speed generally proportional to the real power consumed by the pump. As the level in the wellbore can be maintained at an essentially constant minimum level, despite the relatively large hour-to-hour variations in in-flow which normally occur, the total flow from the formation into the wellbore in a given period of time is increased.

Abstract: A flow control system including a pump for delivering a carrier containing isocratic or gradient controlled elution solvents under pressure to a liquid chromatographic column at a substantially constant selected controlled flow rate.

Abstract: A fluid pump mechanism for delivering a smooth output of fluids to a system utilizing at least one piston in a chamber reciprocative therewithin. The piston has strokes that fill and empty the chamber in conjunction with the action of valve means located at the inlet and outlet of the chamber. Motive means causes reciprocation of the piston within the chamber. Control means is also included for minimizing the time during the piston cycle in which the piston is not emptying the chamber. The invention's scope also encompasses a pressure metering device for a fluid forcing means motivated by an electrical motor.

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: The control system is utilized in a high pressure liquid spraying system including an internal combustion engine, a pump driven by the engine, a source of liquid connected to the pump and a spray nozzle assembly connected by a high pressure conduit to the output of the pump. The control system includes an enclosure and a valve assembly mounted near the pump. The valve assembly is operated by an electric switch mounted on the nozzle assembly and connected to a first solenoid valve in a hydraulic system for operating the valve assembly. The valve assembly includes a hydraulic cylinder which is mounted on the enclosure and which has a plunger positioned to open a ball valve of the valve assembly which is mounted within the enclosure and which is connected to the output of the pump.

Abstract: The disclosure relates to a control apparatus for the preparation of silver halide emulsions in which the flow rates of the reactants can be controlled to provide a desired pAg in the precipitation vessel. Several embodiments are used, depending upon the desired accuracy of pAg. The pAg and flow rate can also be caused to follow programs to maintain constant, or to vary, the pAg during a particular emulsion making process.

Abstract: A controller maintains a constant desired fluid pressure in a fluid load driven by a variable flow fluid pump with a variable speed motor. A set point signal representing desired pressure and a signal from a pressure transducer representing actual pressure are applied to an error amplifier. The resulting error signal is applied through a variable gain stage to the motor control. The variable gain stage includes first and second variable gain amplifiers the first of which has a gain which is controlled inversely to pressure. The second variable gain amplifier has a gain which is controlled in proportion to flow. In this manner, the gain of the controller changes in inverse proportion to the restriction of the fluid load. This makes the performance of the controller independent of changes in the fluid load by keeping the total loop gain constant.

Abstract: A fluid pump mechanism for delivering a smooth output of fluids to a system utilizing at least one piston in a chamber reciprocative therewithin. The piston has strokes that fill and empty the chamber in conjunction with the action of valve means located at the inlet and outlet of the chamber. Motive means causes reciprocation of the piston within the chamber. Control means is also included for minimizing the time during the piston cycle in which the piston is not emptying the chamber. The invention's scope also encompasses a pressure metering device for a fluid forcing means motivated by an electrical motor.

Abstract: A fluid pump mechanism for delivering a smooth output of fluids to a system utilizing at least one piston in a chamber reciprocative therewithin. The piston has strokes that fill and empty the chamber in conjunction with the action of valve means located at the inlet and outlet of the chamber. Motive means causes reciprocation of the piston within the chamber. Control means is also included for minimizing the time during the piston cycle in which the piston is not emptying the chamber. The invention's scope also encompasses a pressure metering device for a fluid forcing means motivated by an electrical motor.