Abstract: An occlusion detection system detects an occlusion in a fluid path of an infusion pump. The infusion pump is for delivering fluid to a user. The infusion pump includes a housing, a motor, a reservoir, one or more drive train components, a sensor, and an electronics system. The motor is contained within the housing. The reservoir contains the fluid to be delivered. The one or more drive train components react to stimulus from the motor to force the fluid from the reservoir into the user. The sensor is positioned to measure a parameter associated with the motor or a drive train component, and the sensor produces three or more output levels across a range of measurements. The electronics system processes the sensor output levels to declare when an occlusion exists.

Abstract: A closed-loop blower includes a blower assembly having a motorized fan that draws ambient air in through an inlet and exhausts air out an outlet. A control circuit is coupled to the motorized fan and a pressure sensing device near the outlet measures pressure of the exhaust air and generates a pressure signal. The control circuit receives the pressure signal and adjusts the speed of the motorized fan to obtain a desired pressure at the outlet. Temperature and motor speed readings may also be detected and input to the control circuit to adjust the speed of the motor and thus the fan. An input device may be provided to adjust the desired pressure values or the control circuit may be programmed with the desired value.

Abstract: In a fire pump adapted to force out the water, which is pumped from a water source, from a nozzle provided at a front end portion of a delivery hose, a nozzle control unit 8 adapted to control the fire pump remotely is provided in the vicinity of the nozzle. The nozzle control unit 8 is connected to a body of the fire pump 1 by power source lines 33. On the nozzle control unit 8, a control instruction unit for instructing an operating mode of the pump 1, and a numerical value display unit for displaying the operation condition of the fire pump are provided. The transmitting and receiving of an operation control signal and a condition display signal are done between the pump 1 and nozzle control unit 8 by power line communication via the power source lines 33, whereby the operation condition of the pump 1 is feedback displayed in real time in response to a control operation of a nozzle operator.

Abstract: A method and apparatus which provides a pressure sensor and/or temperature sensor connected to the low pressure side of a refrigeration system, or the discharge line of a scroll compressor. When the scroll compressor rotates backward, the change of pressure or temperature immediately sends a signal to work with a time-delay relay and a normally closed relay to immediately cut off the electrical power supply to the compressor. Thus, causing the scroll compressor to stop rotating in the undesirable direction.

Abstract: An apparatus and a method for controlling operation of a linear motor compressor, by which a linear motor compressor can operate always in an optimum condition by coping with the load variation due to changes in a refrigerator and the circumstances. In more detail, a current peak value at TDC=0 is detected by comparing a current applied to the linear motor compressor with a formerly detected current, and accordingly the linear motor compressor is operated by a switching control signal generated according to a duty-ratio corresponding to the current peak value.

Abstract: A method and apparatus for automatically detecting an occlusion or drive system failure in a medication infusion system is provided. The electrical current to an infusion pump is measured and compared against a baseline average current. If the current exceeds a threshold amount, an alarm is triggered. Alternatively, pump motor encoder pulses are measured during a pump cycle. If the number of pulses do not correspond within a normal range, an alarm is triggered. After any alarm is triggered, the pump motor is driven in reverse for an incremental distance in order to relieve the fluid pressure in the system.

Abstract: An apparatus and a method for controlling operation of a linear compressor uses a pattern recognition for operating a compressor at an optimum efficiency by recognizing a trace in a graph about relation between a current and a displacement as a pattern and sensing variation of the pattern.

Abstract: A system for remote-controlling a fire pump with a simple wiring construction is provided, being capable of conducting various kinds of control and display. The fire pump control system has an engine, a fire pump, an internal control apparatus, at least one external control apparatus located away from the fire pump including the internal control apparatus, and a twisted pair line for connecting the external control apparatus with the internal control apparatus. The internal and external control apparatuses form a network through the twisted pair line so as to control the fire pump through telecommunications from the external control apparatus. This network uses a p-CSMA system for communicating data, so that a high level of remote control can be carried out, with monitoring an operation state of the fire pump.

Abstract: A thermostat is positioned within a scroll compressor such that a thermostat switch is positioned in the non-orbiting scroll, and a body of the thermostat extends through the crankcase. The thermostat communicates with a heater associated with a motor protector circuit. Current is directed to the heater causing the heater to more promptly stop operation of the scroll compressor. A bias element holds the thermostat securely within the crankcase and non-orbiting scroll such that it will not rattle during operation. Several embodiments of the thermostat are disclosed.

Abstract: There is provided an autonomous inverter-driven hydraulic unit in which a command pressure and command flow rate do not need to be inputted from outside and a pressure and flow rate can be autonomously controlled without requiring any input signal wire. A target horsepower calculation unit 25 of a controller 11 judges which of a plurality of regions a point representing a present operating state belongs to and calculates a target horsepower represented by a point on a target pressure-flow rate characteristic line based on the present pressure and present flow rate. A comparison unit 28 calculates a deviation of this target horsepower and a present horsepower received from a present horsepower calculation unit 26, inputs a control signal representing this deviation to the inverter 3 and controls a rotational number of a variable-speed motor 2 so that the present horsepower coincides with the target horsepower.

Abstract: An apparatus for controlling an operation of a linear compressor includes: a sensorless circuit unit for detecting a current and a voltage applied to a linear compressor and outputting a work operation value corresponding to them; a stroke controller for receiving the work operation value and outputting a switching control signal corresponding to a variation amount of the work operation value; and an electric circuit unit for receiving the switching control signal from the stroke controller and outputting a certain voltage to the linear compressor, accordingly, a TDC of the piston in consideration of an error due to the nonlinear characteristic can be controlled, and thus, an operation efficiency of the linear compressor can be improved.

Abstract: In an apparatus and a method for controlling a linear compressor, an apparatus for controlling a linear compressor includes a linear compressor adjusting a refrigerating capacity by a stroke voltage according to a stroke reference value, a current detecting unit detecting a current applied to the linear compressor, a work operation unit generating a work operation signal by integrating a current detected from the current detecting unit, a suction/discharge pressure difference storing unit storing a suction/discharge pressure difference according to the work operation signal, a microcomputer outputting a switching control signal according to the work operation signal and displaying the suction/discharge pressure difference according to the work operation signal, and an electric circuit unit controlling the linear compressor in accordance with the switching control signal.

Abstract: In an apparatus and a method for controlling operation of a linear compressor, operation of a linear compressor is controlled by finding each inflection point as a TDC (top dead center) is 0 by using a current and a displacement vector generated in the linear compressor, determining a duty ratio on the basis of the inflection point and generating a switching control signal according to the determined duty ratio.

Abstract: In an apparatus and a method for controlling operation of a reciprocating compressor which is capable of operating a compressor stably by detecting a phase difference and using an inflection point of the phase difference, an apparatus and a method for controlling operation of a reciprocating compressor including an electric circuit unit operating a reciprocating compressor by varying a stroke with motion of a piston, a phase difference detecting unit detecting a phase difference of a current and a voltage from the electric circuit unit, a phase inflection point detecting unit detecting a phase inflection point by being inputted the phase difference, and a stroke controlling unit being inputted the detected phase inflection point from the phase inflection point detecting unit and applying a voltage, to the electric circuit unit in order to make the stroke correspond to the phase inflection point can control a TDC of a piston regardless of load variation, improve an operation efficiency of a reciprocating compr

Abstract: A method and apparatus for achieving constant air flow rate economically utilizes an induction blower motor with control settings determining the motor excitation voltage. A memory stores, for a variety of motor speeds, a graph of the speeds plotted against a proportionality constant of flow rate to fan speed for the selected motor system on one axis and motor control settings on the other axis. The only monitoring necessary to achieve the constant flow rate is thus the sensing of fan rotational speed. The measured fan speed is compared against the proportionality constant needed for the selected constant air flow rate and a motor excitation voltage is derived to achieve that proportionality constant. When the system load changes significantly, thereby causing significant fan speed change, a cascaded control loop is used whereby the speed changed induced by each control voltage adjustment is monitored until the desired constant flow rate is again attained at the new load level.

Abstract: A scroll compressor is provided with a motor protector mounted at a location remote from the motor. The motor protector is of the sort which operates to stop operation of the motor both when the temperatures in the scroll compressor increases, and when the electrical characteristics of the power supplied to the motor depart from those from which are expected. Preferably, the motor protector is mounted in the non-orbiting scroll. Further, the invention includes means to increase the sensitivity of this motor protector to conditions indicative of an outdoor fan failure. In several embodiments, these means include a valve which opens to communicate hot discharge pressure refrigerant over the valve. In one other embodiment, this means is a heat sink operable to take heat away from the motor protector. In this last embodiment, when the volume flow of refrigerant decreases, the amount of heat taken away also decreases.

Abstract: An electronic control system dynamically varies the output capacity of a compressor by controlling plural valves associated with the compressor to provide pressurized air to a distribution system at an appropriate rate. The control system operates in any of three modes for standalone operation, including continuous run, auto/dual pressure band, and target pressure modes. In the first two modes, pressure bands are dynamically calculated based on load and unload values entered by an operator. These electronic control systems can also be connected in a peer-to-peer network to coordinate control of up to 16 compressors feeding the same distribution system, so as to maintain a desired target pressure in the system. A modem connected to the system supports remote diagnostics, monitoring, and control. Specialized startup, operating, and shutdown diagnostic algorithms prevent damage to the compressor and avert unsafe operating conditions.

Abstract: A liquid pump and controller with separate pump activation and deactivation mechanisms that are both closed detector devices is provided. The pump activation mechanism includes a float device that activates a pump motor when water within a housing of the pump reaches a high water level. The pump deactivation mechanism includes a sensor that detects the load on the pump motor and deactivates it when the sensed load indicates that the water within the pump housing has reached a low water level.

Abstract: An occlusion detection system detects an occlusion in a fluid path of an infusion pump. The infusion pump is for delivering fluid to a user. The infusion pump includes a housing, a motor, a reservoir, one or more drive train components, a sensor, and an electronics system. The motor is contained within the housing. The reservoir contains the fluid to be delivered. The one or more drive train components react to stimulus from the motor to force the fluid from the reservoir into the user. The sensor is positioned to measure a parameter associated with the motor or a drive train component, and the sensor produces three or more output levels across a range of measurements. The electronics system processes the senor output levels to declare when an occlusion exists.

Abstract: A multi-stage blowdown valve is provided that uses a single control signal to simultaneously decompress the interstage and the second stage in a compressor system. The valve uses a series of sliding spools located linearly within a single bore to either prevent or allow fluid communication between two isolated passageways each having an inlet port and a discharge port. The valve, when used as a two stage blowdown valve in a multi-stage compressor system, can prevent compressor failure from occurring by ensuring that both the interstage and the second stages are decompressed. not only the interstage.

Abstract: An electronic control system is disclosed to control and to prevent damage to a standalone or a network of oil free, two stage compressor packages. The electronic control system uses pressure and temperature sensors to detect actual shutdown conditions or predict shutdown conditions based on the operating state of the compressor package and the current temperatures or pressures of the air at strategic locations in the compressor package. It has been determined through experimentation that, if the pressure at the inlet of the stage two compressor is less than the discharge pressure of the stage two compressor by more than an allowable value, then a high temperature condition will occur in the stage two compressor and cause the compressor to seize.

Abstract: A safety device for use in a fluid transfer and/or circulation system of the type which uses a pump to draw water from a reservoir through one or more intake lines each extending from an open end at the reservoir to the pump intake. The safety device connects to the fluid transfer/circulation system and includes a sensor, a triggering mechanism, and a vacuum breaker. When the pump is operating, the sensor monitors one or more conditions of the system. When one or more of the monitored conditions deviates outside of a normal operational range, as a result of an obstruction of any one or more of the open ends of the intake lines, the triggering mechanism triggers the vacuum breaker to eliminate negative pressure in the system by introducing air from atmosphere into the intake lines, thereby removing suction at the open ends of the intake lines. The safety device may further activate warning devices including audible and visible alarms to indicate that the system has been deactivated.

Abstract: In a capacity control method for an oil-free screw compressor, when an air consumption is larger than a set amount, a rotation frequency of a motor using an inverter to drive the compressor is set to be variable. When the air consumption is a set air amount or less, the inverter is controlled in such a manner that the rotation frequency of the motor is kept at a constant value. In this state, when an operation gas pressure of the compressor reaches an upper-limit value, an air release valve is opened to discharge the operation gas to the atmosphere. Additionally, the rotation frequency of the motor is lowered to a lower-limit value. Re-compression in the compressor can be prevented, and a compressor drive torque is lowered.

Abstract: An electronic control system dynamically varies the output capacity of a compressor by controlling plural valves associated with the compressor to provide pressurized air to a distribution system at an appropriate rate. The control system operates in any of three modes for standalone operation, including continuous run, auto/dual pressure band, and target pressure modes. In the first two modes, pressure bands are dynamically calculated based on load and unload values entered by an operator. These electronic control systems can also be connected in a peer-to-peer network to coordinate control of up to 16 compressors feeding the same distribution system, so as to maintain a desired target pressure in the system. A modem connected to the system supports remote diagnostics, monitoring, and control. Specialized startup, operating, and shutdown diagnostic algorithms prevent damage to the compressor and avert unsafe operating conditions.

Abstract: A mini-environment control device includes an individual enclosure to contain a sample and to isolate it from the external environment. An array of micropumps attached to the individual enclosure generates and maintains a controlled vacuum in the individual enclosure. Transfer means introduce the sample into the individual enclosure and extract it therefrom. The micropumps of the array of micropumps can be of a type employing the thermal transpiration effect. Temperature and pressure microsensors and a gas analyzer enable the operation of the array of micropumps to be controlled by an onboard microcomputer. The atmosphere surrounding a sample is therefore controlled.

Abstract: A pump control system and method employs a variable drive for controlling the speed of an AC electric motor driving a cyclic load. A real-time tuning of the frequency and voltage of the AC input to the motor allows a controlled variation of a cycle speed of the cyclic load. The control system and method adjusts motor speed according to a desired motor speed characteristic for different portions of a complete cycle and over multiple cycles of the cyclic load. The variable drive rectifies a poly-phase AC power input to provide a source of DC power on a DC bus and periodically samples the DC bus current and DC bus voltage across the DC bus to optimize the motor operation.

Abstract: A dynamometer readout (42, 46) and method is disclosed for obtaining dynamometer information (110) related to pumpjacks (10). For this purpose, a change of pivotal direction of the walking beam (18) may be detected by processor (82) utilizing an encoder component (60) with spaced slots (64) therein and light signal devices (68, 70, 72, 74) positioned to have a spacing different from that of the spacing of the slots (64). Software techniques filter out effects of stray mechanical vibrations. An infrared transceiver (46, 50, 100) of a preferred embodiment includes a radio frequency carrier generator (90) and modulator (88) that produces an infrared signal receivable by a low cost consumer radio receiver. The radio frequency modulation technique for infrared signals (96) and related filtering (98, 102, 104) condition formatted infrared signals for utilization in daylight and through a car window for drive-by downloading of data to second computer (108). A sensor (163) may be substituted for the encoder.

Abstract: An inventive scroll compressor has its motor protector circuit mounted on the compressor pump unit. In this way, increased temperature from reverse rotation of the orbiting scroll causes the motor protector unit to quickly stop operation of the motor. Preferably, the motor protector unit is mounted on the non-orbiting scroll.

Abstract: An apparatus and method of controlling air compressors is disclosed. In this invention, an air compressor is started to supply compressed air to an air tank. A temperature sensor senses the lubrication oil temperature of the compressor, and outputs a temperature signal to the controller, which compares the sensed oil temperature with a preset reference temperature. When the sensed oil temperature is not higher than the preset reference temperature, a pressure sensor senses the compressed air pressure within the tank, and outputs a pressure signal to the controller. When the compressed air pressure is higher than a minimum pressure, the controller lowers the frequency of a drive signal for the air compressor and operates the air compressor at a low rpm. When the compressed air pressure is higher than a preset maximum pressure, the controller operates the air compressor at a minimum rpm and partially discharges compressed air from the tank into the atmosphere.

Abstract: A liquid pump and controller with separate pump activation and deactivation mechanisms that are both closed detector devices is provided. The pump activation mechanism includes a float device that activates a pump motor when water within a housing of the pump reaches a high water level. The pump deactivation mechanism includes a sensor that detects the load on the pump motor and deactivates it when the sensed load indicates that the water within the pump housing has reached a low water level.

Abstract: A multi-stage blowdown valve is provided that uses a single control signal to simultaneously decompress the interstage and the second stage in a compressor system. The valve uses a series of sliding spools located linearly within a single bore to either prevent or allow fluid communication between two isolated passageways each having an inlet port and a discharge port. The valve, when used as a two stage blowdown valve in a multi-stage compressor system, can prevent compressor failure from occurring by ensuring that both the interstage and the second stages are decompressed, not only the interstage.

Abstract: A multi-stage blowdown valve is provided that uses a single control signal to simultaneously decompress the interstage and the second stage in a compressor system. The valve uses a series of sliding spools located linearly within a single bore to either prevent or allow fluid communication between two isolated passageways each having an inlet port and a discharge port. The valve, when used as a two stage blowdown valve in a multi-stage compressor system, can prevent compressor failure from occurring by ensuring that both the interstage and the second stages are decompressed. not only the interstage.

Abstract: A method and apparatus for automatically detecting an occlusion or drive system failure in a medication infusion system is provided. The electrical current to an infusion pump is measured and compared against a baseline average current. If the current exceeds a threshold amount, an alarm is triggered. Alternatively, pump motor encoder pulses are measured during a pump cycle. If the number of pulses do not correspond within a normal range, an alarm is triggered. After any alarm is triggered, the pump motor is driven in reverse for an incremental distance in order to relieve the fluid pressure in the system.

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 is indicative of a correction factor to be applied to the pump.

Abstract: A multi-stage blowdown valve is provided that uses a single control signal to simultaneously decompress the interstage and the second stage in a compressor system. The valve uses a series of sliding spools located linearly within a single bore to either prevent or allow fluid communication between two isolated passageways each having an inlet port and a discharge port. The valve, when used as a two stage blowdown valve in a multi-stage compressor system, can prevent compressor failure from occurring by ensuring that both the interstage and the second stages are decompressed, not only the interstage.

Abstract: Systems and related methods pump fluid through a pump having a stroke volume. The systems and methods employ gravimetric control measures to monitor fluid flow through the pump. An actuator interacts with the pump during a stroke interval (TStroke) to pump fluid through the pump. The systems and methods couple a receptacle to the pump, to either dispense fluid into the pump or to receive fluid from the pump. The systems and methods detect changes in weight of the receptacle over a sample time period. The systems and methods achieve a desired flow rate (QDesired) by deriving an actual flow rate (QActual) by sensing changes in weight of the receptacle over the sample time period, taking into account the density of the fluid, and adjusting the stroke interval based upon QActual so that QDesired is achieved.

Abstract: A dynamometer readout (42, 46) and method is disclosed for obtaining dynamometer information (110) related to pumpjacks (10). For this purpose, a change of pivotal direction of the walking beam (18) may be detected by processor (82) utilizing an encoder component (60) with spaced slots (64) therein and light signal devices (68, 70, 72, 74) positioned to have a spacing different from that of the spacing of the slots (64). Software techniques filter out effects of stray mechanical vibrations. An infrared transceiver (46, 50, 100) of a preferred embodiment includes a radio frequency carrier generator (90) and modulator (88) that produces an infrared signal receivable by a low cost consumer radio receiver. The radio frequency modulation technique for infrared signals (96) and related filtering (98, 102, 104) condition formatted infrared signals for utilization in daylight and through a car window for drive-by downloading of data to second computer (108). A sensor (163) may be substituted for the encoder.

Abstract: A multi-stage blowdown valve is provided that uses a single control signal to simultaneously decompress the interstage and the second stage in a compressor system. The valve uses a series of sliding spools located linearly within a single bore to either prevent or allow fluid communication between two isolated passageways each having an inlet port and a discharge port. The valve, when used as a two stage blowdown valve in a multi-stage compressor system, can prevent compressor failure from occurring by ensuring that both the interstage and the second stages are decompressed, not only the interstage.

Abstract: A forecourt fuel pump has a casing locating means for metering and delivering to a flexible hose liquid fuel to be dispensed, and a processing unit arranged to monitor and control the delivery of fuel and the display of information concerning that delivery. The pump is provided with at least one sensor for an environmental parameter associated with the pump, such as the sensing of hydrocarbon liquids in the casing. Further sensors external of the pump may be provided to sense other parameters such as the presence of hydrocarbon vapor or liquids. Each sensor provides an output which is supplied to the processing unit which is arranged to monitor the output and provide an indication if the sensed value falls outside a pre-set range.

Abstract: An electronic control system dynamically varies the output capacity of a compressor by controlling plural valves associated with the compressor to provide pressurized air to a distribution system at an appropriate rate. The control system operates in any of three modes for standalone operation, including continuous run, auto/dual pressure band, and target pressure modes. In the first two modes, pressure bands are dynamically calculated based on load and unload values entered by an operator. These electronic control systems can also be connected in a peer-to-peer network to coordinate control of up to 16 compressors feeding the same distribution system, so as to maintain a desired target pressure in the system. A modem connected to the system supports remote diagnostics, monitoring, and control. Specialized startup, operating, and shutdown diagnostic algorithms prevent damage to the compressor and avert unsafe operating conditions.

Abstract: A method for controlling working fluid surge in a centrifugal compressor. According to the method, surge detection is accomplished by calculating the change in the compressible fluid mass flow rate that accompanies surge in a compressor, the compressor having means for sensing a first fluid temperature, means for sensing a first pressure, means for sensing a second pressure, and means for measuring current drawn by a compressor prime mover, the method comprising the steps of: calculating the time rate of change of the first fluid temperature; calculating the time rate of change of the first fluid pressure; calculating the time rate of change of the second fluid pressure; calculating the time rate of change of current drawn by the compressor prime mover; calculating the mass flow rate by combining the calculated rates of change; and comparing the calculated mass flow rate to a predetermined acceptable mass flow rate to determine if surge is present.

Abstract: A method is disclosed for identifying when a compressor is being run in reverse due to improper wiring. In a preferred embodiment, sensors sense the condition of a refrigerant at the inlet line and a refrigerant at the outlet line. If an expected pressure differential is not seen, then the determination is made that the compressor is running in reverse. In embodiments the control system may shut down the compressor, provide an alarm, or reverse a phase of two of the three wires of a three phase power input to correct the rotation direction.

Abstract: A dynamometer readout (42, 46) and method is disclosed for obtaining dynamometer information (110) related to pumpjacks (10). For this purpose, a change of pivotal direction of the walking beam (18) may be detected by processor (82) utilizing an encoder component (60) with spaced slots (64) therein and light signal devices (68, 70, 72, 74) positioned to have a spacing different from that of the spacing of the slots (64). Software techniques filter out effects of stray mechanical vibrations. An infrared transceiver (46, 50, 100) of a preferred embodiment includes a radio frequency carrier generator (90) and modulator (88) that produces an infrared signal receivable by a low cost consumer radio receiver. The radio frequency modulation technique for infrared signals (96) and related filtering (98, 102, 104) condition formatted infrared signals for utilization in daylight and through a car window for drive-by downloading of data to second computer (108).

Abstract: An improved electrical submersible pump is disclosed in which a processor downhole is utilized to monitor one or more subsurface conditions, to record data, and to alter at least one operating condition of the electrical submersible pump. Novel uses are described for downhole gas compression, the delivery of particulate matter to wellbore sites, and for the disposal of waste.

Abstract: A medical perfusion system for use in connection with the medical treatment of a patient is provided with a first type of perfusion device in the form of a blood pump adapted to pump blood through a fluid conduit connected to the patient and a second type of perfusion device in the form of a sensing device adapted to sense a condition and generate a sensing signal relating to the condition. The perfusion system also includes an electrical power network having an electrical power line, means for selectively connecting the perfusion devices to the electrical power network, and a controller with an input device for accepting control commands from an operator. The perfusion system could also include a control device, such as a pump, a plurality of sensing devices, and means for specifying the sensing device that the control device should be accept feedback from.

Abstract: An electronic control system is disclosed to control and to prevent damage to a standalone or a network of oil free, two stage compressor packages. The electronic control system uses pressure and temperature sensors to detect actual shutdown conditions or predict shutdown conditions based on the operating state of the compressor package and the current temperatures or pressures of the air at strategic locations in the compressor package. It has been determined through experimentation that, if the pressure at the inlet of the stage two compressor is less than the discharge pressure of the stage two compressor by more than an allowable value, then a high temperature condition will occur in the stage two compressor and cause the compressor to seize.

Abstract: A system for optimizing progressive cavity pump operation during oil and gas recovery is provided. By strategically disposing a plurality of sensors along the production tubing and sucker rod strings, progressive cavity pump operation and performance may be monitored real-time. As an important indicia of pump performance, dynamic fluid level is provided to the operator/end user on a real-time basis. Prerequisite to achieving pump optimization, dynamic fluid level and other pertinent data are analyzed and enables corrections to be made in the pumping system during operation. A computer system having sufficient inherent and adaptable expertise is provided to interpret pump conditions based upon a plurality of variables and parameters to increase or decrease pump production and to maintain a dynamic fluid level determined to be optimal or otherwise advantageous by the end user.

Abstract: This invention provides a method for controlling slurry pump performance to better operate the pump and increase system operating stability. Such control is achieved by determining the instantaneous pressure produced by the pump (and the internal specific gravity that goes along with that) and using this pressure value along with the overall total pipeline resistance to determine the optimal instantaneous operating speed of the pump. When the pump is controlled in this manner, the adverse cavitation, wear, and other effects on the pump and pipeline associated with unstable system operation can be reduced or avoided.

Abstract: An apparatus for generating water currents in a swimming pool is provided in which an intake chamber, a discharge channel and a pump impeller are contained within a common housing. The discharge channel is defined within an open-ended discharge tube which extends longitudinally within the cylindrical housing. In use, the pump operates to suck water into the intake chamber around the tube through the front end of the housing. The water flows around the rear end of the discharge tube into the discharge chamber where it is expelled forcibly into the swimming pool through the discharge outlet at the open front end of the discharge tube. A pump stator member with radially extending guide vanes is provided in the discharge tube in front of the impeller to reduce swirling in the discharge channel. A safety guard may be provided over the inlet and the outlet at the front end of the housing.

Abstract: A compressor controller provides integrated monitoring, control, and alarm capabilities. The compressor controller receives a run signal from a rack controller. Upon receipt of the run signal, the compressor controller monitors startup conditions to determine whether it is safe to start the compressor. If so, the compressor controller applies power to the compressor and determines whether the compressor is running properly. Once the compressor is running properly, the compressor controller continues to monitor the operation of the compressor. If the compressor controller detects a fault conditions during the startup or operation of the compressor, the compressor controller provides an alarm signal and shuts down the compressor if necessary. The compressor controller provides maximum protection for the compressor by monitoring a plurality of relevant conditions and by shutting the compressor down when necessary.