Abstract: A dry suction fitting assembly is provided for drawing water from a spa, whirlpool bathtub or other suitable water tub to a pump, featuring a suction body for arranging in relation to a wall of the spa, whirlpool bathtub or other suitable water tub. The suction body is arranged in relation to a wall of the spa, whirlpool bathtub or other suitable water tub, has a suction inlet for coupling to the pump, and has an internal surface with an equilibrium tube arranged therein with three openings, a first opening that acts as a water flow inlet, a second opening that is open to the atmosphere via a connection hose or other suitable connection device and that is filled with water during normal operation, and a third opening that is a safety orifice coupled to the suction inlet. During normal operation water flows from the first opening, through the equilibrium tube, and out the third opening.

Abstract: Digital fluid pumps having first and second electromagnetic actuators formed in part by a piston to alternately drive the piston in opposite directions for pumping purposes. The piston motion is intentionally limited so that the electromagnetic actuators may operate with a high flux density to provide an output pressure higher than that obtained with conventional solenoid actuated pumps. The electromagnetic actuator coils are electrically pulsed for each pumping cycle as required to maintain the desired fluid flow and output pressure, with the piston being magnetically latchable at one or both extreme positions between pulses. Alternate embodiments and control methods and systems are disclosed.

Abstract: A method and apparatus for detecting the occurrence of surge or incipient surge in a centrifugal compressor is supplied. The centrifugal compressor has an inlet passage, an inlet passage wall and an impeller. When flowing a fluid through the centrifugal compressor thereby establishing a fluid flow in the inlet passage, the fluid flow is measured in the inlet passage proximate the inlet passage wall and proximate the impeller. The measurements may include detecting a reverse in the fluid flow direction, measuring a tangential component to the fluid flow, measuring a substantial decrease in the axial fluid flow, and/or measuring the fluid temperature. Fluid flow in the compressor can then be modified or controlled to prevent surge.

Abstract: For a motor that drives a compressed air generator, three operating modes which includes a powerful mode for rotating a motor in a high speed range, a silent mode for rotating the motor in a low speed range, and an automatic mode for automatically changing the rotation speed of the motor from the low speed to the high speed in accordance with a setup condition are prepared. A user can designate a desired operating mode by using an operating mode selection switch.

Abstract: A method for controlling an airless sprayer (10) having an electronic control (12) with a user selectable pressure setpoint monitors the actual output pressure developed by the pump (14). When the pump output pressure drops to a selectable percentage of the setpoint, the control displays an empty message and the unit shuts off.

Abstract: Compressed gases are gathered from a plurality of compressors and employed if required. A pressure of compressed gas thus gathered is measured by a pressure sensor to generate a pressure signal, which is transmitted to a control. The signal is transmitted from the control to electromagnetic switches to control motors for the compressors to determine which of the compressors run.

Abstract: A sump draining apparatus having a pressure transducer engaged in a receptacle that is in turn engaged in an open-ended collar of a housing. The receptacle and thus the pressure transducer is slideable in the axial direction into and out of the open-ended collar. The housing is generally cylindrical and contains a pump and motor, each of which has a generally cylindrical shape and is axially stacked in the housing. A cord having a vent and electrical leads for the pressure transducer is releasably engaged via a cord restraint at one end portion of the housing and the pressure transducer is releasably engaged in the receptacle in the open-ended collar at the other end of the housing. The receptacle and sensor may be removed, serviced, and/or replaced without the housing being opened and without the pump and motor being removed.

Abstract: Compressor controls in a compressed gas system provide a variable frequency controlled refrigerant compressor in a dehydrator for compressed air or other gases. The system detects changes in a demand on the pneumatic air supply by monitoring a pressure of a refrigerant system associated with the air supply. Based on the changes in the refrigerant system pressure, a motor speed controller generates and sends a control signal to the variable speed compressor to adjust the speed of the variable speed compressor based on the demand in the air supply.

Abstract: A system for detecting liquid in an inground lift has a tube with an open end disposed within the internal cavity defined by the containment housing of the inground lift. The tube is in fluid communication with a source of pressurized gas. A pressure sensor generates a signal if the pressure within the air line exceeds a predetermined level, which occurs if the end is blocked by liquid. A control system is configured to respond to the signal.

Abstract: A method is provided for regulating fluid pump pressures by detecting an elevation differential between a fluid flow control device and the distal end of a fluid line in communication with the fluid flow control device. A fluid flow control device, for instance a peritoneal dialysis device, is at a first height, a distal end of a fluid line is at a second height, and a valved outlet, when open, affords communication between the fluid flow control device and the distal end of the fluid line. The elevation differential is correlatable with a pressure measurable during a calibration procedure provided as a part of the methodology.

Abstract: The present invention pertains to methods and apparatus for controlling the pressure in a supercritical processing system. Active methods for controlling the pressure include anticipating a pressure deviation due to a solute addition to a system, and changing the pressure within the system to compensate for the deviation. In this way, a desired pressure is achieved when the solute is added, without phase separation of the solute from the solvent. Pressure is adjusted by changing the volume of the supercritical processing system. Passive methods include adjusting the pressure of a supercritical system by changing the volume in response to a pressure deviation from a desired pressure. Apparatus for controlling the pressure in a supercritical processing system are described.

Abstract: A sump draining apparatus having an pressure transducer engaged in a receptacle that is in turn engaged in an open-ended collar of a housing. The receptacle and thus the pressure transducer is slideable in the axial direction into and out of the open-ended collar. The housing is generally cylindrical and contains a pump and motor, each of which has a generally cylindrical shape and is axially stacked in the housing. A cord having a vent and electrical leads for the pressure transducer is releasably engaged via a cord restraint at one end portion of the housing and the pressure transducer is releasably engaged in the receptacle in the open-ended collar at the other end of the housing. The receptacle and sensor may be removed, serviced, and/or replaced without the housing being opened and without the pump and motor being removed.

Abstract: A water supply system has its housing and pressure tank sized so that the pressure tank fits within the housing, thus avoiding the need for another separate opening in the ground for the pressure tank. With this arrangement, there is less work in installation of the system and in maintaining the system. A control box for the system can be in the housing near the top where it is accessible or it can be separate. Preferably, the pump will be driven by a variable speed pump or a stop cycle valve will be used. Preferably, the pressure tank has a capacity of less than 40 gallons and the housing has an enlarged portion and a reduced portion with the pressure tank being mounted within said enlarged portion of said housing.

Abstract: A system for the collection of physiological fluids includes a vacuum source (14) that is controlled to provide low vacuum as a function of whether fluids are entering the system. The suction wand and associated tubing are made of thin flexible materials, and the pressures employed do little damage to the collected fluids.

Abstract: A pressure maintenance assembly for a domestic water well system. The assembly includes a pressure maintenance valve having an inlet side and an outlet side, a pressure tank in fluidic communication with the outlet side, and a calibrated bypass. When the valve is closed, the calibrated bypass provides fluidic communication between the inlet side and the outlet side. The size of the calibrated bypass and the pressure tank are adapted and constructed to permit a flow rate between the inlet side and the outlet side that will fill the pressure tank in a time interval at least as great as but less than twice the time required to pump a volume of water that will dissipate heat generated by the pump when it is turned on.

Abstract: A pneumatic pump control system for sequentially switching on and off an electrically operated pump disposed in a waste water liquid storage tank The pneumatic pump control system comprises a pneumatic pressure accumulator that is disposed within the liquid storage tank at a predetermined level. The pneumatic pressure accumulator is a dome-type that defines an interior air chamber for containing air, and a lower opening disposed at an elevation that represents a zero reference level within the tank. The lower opening is in communication with the liquids in the liquid storage tank when the level of liquid is as high as the lower opening. A pressure transducer is operatively connected to the pneumatic pressure accumulator for communication with the interior air chamber to measure the differential air pressure between the air within the interior air chamber and the upper layer of air within the liquid storage tank.

Abstract: A water supply system has its housing and pressure tank sized so that the pressure tank fits within the housing, thus avoiding the need for another separate opening in the ground for the pressure tank. With this arrangement, there is less work in installation of the system and in maintaining the system. The control box for the system can be in the housing near the top where it is accessible or can be separate. Preferably, the pump will be driven by a variable speed pump or a stop cycle valve will be used.

Abstract: A soap dispensing system includes non-pressurized first and second soap containers connected to a soap manifold. The manifold has a first inlet connection to the first soap container and a second inlet connection to the second soap container. There is a soap outlet on the manifold. A soap conduit extends from a first dispensing opening on the manifold to a second dispensing opening on the manifold. A two direction peristaltic pump is associated with the soap conduit to move soap either from the first dispensing opening to the second dispensing opening or in the opposite direction. There are valves within the soap manifold for connecting the first inlet, first dispensing opening, second dispensing opening, second inlet opening, and the outlet to provide soap, upon operation of the pump, from one of said containers, through said soap conduit, to the manifold outlet.

Abstract: A method and system for determining pump cavitation is disclosed. In accordance with the principle of the invention, changes in dynamic fluid pressure within a pump are monitored and compared to a determined cavitation alarm pressure. The determined cavitation pressure is determined as a known percentage of a known non-cavitation pressure. Fluid cavitation is determined when the change in dynamic fluid pressure falls below the determined cavitation alarm pressure. In a further aspect of the invention, a remaining mechanical seal operational life can be determined by maintaining a total time of fluid cavitation and reducing the expected life by the known operational time of the pump and the time the pump is in cavitation.

Abstract: A grout slurry pumping system, and a grout slurry control box and associated tools are described. Methods of using the pumping system and control box are also described. The pumping system and control box may be used separately or together. The pumping system maintains a grout slurry of desired consistency and can provide it through a hose to remote locations. The control box operates to apply grout to a work surface in desired quantities and in desired amounts according to a control valve.

Abstract: Flow parameters in a fluid delivery assembly are determined by monitoring pressure responses and processing those responses along with information regarding the fluid flow. In one aspect, a processor controls the pump to pump flow quantities in accordance with a pseudorandom code. Portions of the resulting pressure signal sensed at the conduit is averaged, and the averaged values are then decoded in accordance with the pseudorandom code. An estimate of the equilibrium pressure is generated from the decoded average pressure values, while a summation of the pressure samples is generated from the undecoded pressure signals. The resistance to fluid flow of the system is determined from the estimated equilibrium pressure and pressure summation. For low flow rates, a processor controls the pump to pump fluid in a series of fluid boluses, with each fluid bolus delivered in the beginning of a separate timeslot.

Abstract: A tank (1) having saturated water (2) is connected to a pump (5) via a suction line (4). The actual values of the pressure and/or temperature in the tank (1) are detected to a measuring arrangement (7) and supplied to a control apparatus (8), in which the actual values are compared with fixed values. In a water reservoir (9) there is admixing water, the temperature of which is lower than the actual temperature in the tank (1). This water reservoir (9) is connected to the suction line (4) via an inflow line (11). An actuator (12) which is activated by the control apparatus (8) is arranged in the inflow line (11). When the actual values in the tank (1) reach the fixed values, so that the pump (5) could experience cavitation, the actuator (12) is opened by means of the control apparatus (8), in order to introduce admixing water into the suction line (4).

Abstract: A grout slurry pumping system, and a grout slurry control box and associated tools are described. Methods of using the pumping system and control box are also described. The pumping system and control box may be used separately or together. The pumping system maintains a grout slurry of desired consistency and can provide it through a hose to remote locations. The control box operates to apply grout to a work surface in desired quantities and in desired amounts according to a control valve.

Abstract: Hydraulic actuator. An actuator body includes an inlet, an outlet, a port communicating with a pre-charged diaphragm tank, and a port communicating with a pressure switch. The actuator body includes a movable member which, in a first position, closes the inlet port and provides fluidic communication with the pressure switch port while allowing pressure equalization between the inlet and an interior of the actuator body. In a second position, the movable body opens the inlet port and seals the pressure switch port. A spring is disposed within the actuator body to urge the movable member toward the first position. The invention eliminates the need for multiple springs as shown in one prior art design and eliminates the need for reliance on a hydrostatic force differential to move the movable member.

Abstract: An on-board reductant delivery system for a motor vehicle includes a mixer/nozzle system for connection to an exhaust system of a motor vehicle. The on-board reductant delivery system also includes a fluid metering system connected to the mixer/nozzle system for metering reductants to the mixer/nozzle system. The on-board reductant delivery system further includes an air supply system connected to the mixer/nozzle system for delivering pressurized air to the mixer/nozzle system. The mixer/nozzle system mixes the reductants and pressurized air and sprays the mixture in the exhaust system of the motor vehicle to reduce NOx.

Abstract: The centrifugal pump unit includes a flow switch arranged within the pump housing in the flow path of a delivery fluid, which essentially consists of an electromagnetic switch device and a two-armed, pivotably mounted lever whose one arm projects into the flow path and whose other arm carries a magnet which is in contact-free active connection with the switch device. The switch device is arranged within a terminal box mounted on the unit housing. The lever is seated within a switch housing which is incorporated in a cartridge-like manner into the pump housing and which is hermetically sealed to the outside and which is arranged neighbouring the terminal box that such it is only in magnetic active connection so that the reed contact located in the terminal box is controlled by the magnet located in the switch housing. In this manner a usual terminal box may be used which does not need to be sealed with respect to the delivery flow.

Abstract: They are characterized in that, when the pressure at the measurement point reaches or exceeds the start-up pressure value and/or when the flow provided by the pumping devices is lower than the consumption flow, the flow provided by the station increases by a step, and, when the pressure at the measuring point reaches the stop pressure value and/or when the flow provided by the pumping devices exceeds the consumption flow, the flow provided by the station reduces by a step. According to another embodiment, a pumping device stops or remains in operation without pumping (“stand by”) when said pumping device is in operating conditions such that there could be a reduction of life of the pumping device or overheating of same. Significant energy saving and longer useful life of pumping devices is achieved.

Abstract: Hydraulic actuator. An actuator body includes an inlet, an outlet, a port communicating with a pre-charged diaphragm tank, and a port communicating with a pressure switch. The actuator body includes a movable member which, in a first position, closes the inlet port and provides fluidic communication with the pressure switch port while allowing pressure equalization between the inlet and an interior of the actuator body. In a second position, the movable body opens the inlet port and seals the pressure switch port. A spring is disposed within the actuator body to urge the movable member toward the first position. The invention eliminates the need for multiple springs as shown in one prior art design and eliminates the need for reliance on a hydrostatic force differential to move the movable member.

Abstract: An apparatus and method of rehabilitating the stagnant bottom of water wells using existing well equipment including a pump and a pressure tank, augmented by valves and a conduit that extends from the surface to near the bottom of the stagnant region at the well bottom. Water pumped from the well is returned under pressure to the well bottom where it displaces the fouled contents of the stagnant region at the well bottom. This elevates the contents of the well bottom to a position above the pump intake, where the contents can then be pumped to waste.

Abstract: A fluid pressure source apparatus includes a pump, an accumulator for receiving pressure from the pump, a pressure switch for detecting the pressure in the accumulator, an electric motor for driving the pump, and a motor control device for driving the motor when the pressure switch detects a low pressure. A current detecting device detects a motor current value of the motor and a control unit determines whether the accumulator or the motor is experiencing an abnormality based on the motor current value. The control unit determines whether the motor current value occurring during a first set time following the start of driving of the motor is greater than a first set value. If the motor current value is not greater than the first set value, the control unit determines that the current detecting device is experiencing an abnormality. If there is no such abnormality information, the control unit compares the motor current value with predetermined values.

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: A diaphragm-type pressurizing pump having a water stopper structure, in which an upper lid of the pump having a pressurizing room being provided on top of the pressurizing pump, wherein the water stopper structure including mainly a valve body and a valve lid is provided on the upper lid of the pump, a water stopper valve set is provided between the water stopper structure and the upper lid of the pump, wherein communicating water inlet holes are provided on the upper lid of the pump and the valve body and are located on the side of the water inlet, a guide groove having a pressurizing hole is formed on the top of the valve body, a water outlet of the upper lid of the pump is provided with a hole communicating with the pressurizing room, the hole is under the water stopper valve set, the flow between the pressurizing room and the water outlet are blockaded with the water stopper valve set so that the upper lid of the pump has the function of stopping water, and also can save space and save cost.

Abstract: Apparatus for delivering a water treatment chemical to a water intake in a water system is disclosed. The water system has a water inlet and a pump for withdrawing water from a natural body of water, such as an underground aquifer, a river, a lake or the like. In a water system that draws water from a body of water that is inhabited by zebra mussels, the apparatus is operable, when water is being drawn into the system, to deliver a zebra mussel control agent to the inlet of the system to eliminate zebra mussels, if present, from the water system and to prevent the infestation of the water system by zebra mussels. In a water system that draws water from an underground aquifer, the apparatus is operable, when the system is drawing water, to deliver a water treatment chemical to or near the water inlet for the system and to cause thorough mixing of the water treatment chemical with the water, before it reaches a reservoir in the system, whereby undesired impurities are controlled or removed from the water.

Abstract: Hydraulic actuator. An actuator body includes an inlet, an outlet, a port communicating with a pre-charged diaphragm tank, and a port communicating with a pressure switch. The actuator body includes a movable member which, in a first position, seals the inlet port and provides fluidic communication with the pressure switch port. In a second position, the movable body opens the inlet port and seals the pressure switch port. A spring is disposed within the actuator body to urge the movable member toward the first position. The invention eliminates the need for multiple springs as shown in one prior art design and eliminates the need for reliance on a hydrostatic force differential to move the movable member.

Abstract: A system for optimizing pump operation during oil and gas recovery is provided. By strategically disposing a plurality of sensors along the production tubing and sucker rod strings, 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. The system is designed with a panoply of configurations to accommodate remote administration of many wells by using serial communication and remote transmitting devices.

Abstract: A fluid pressure source apparatus has a pump, an accumulator, a pressure switch, and a control device for turning on and off the pump in accordance with the signal from the pressure switch. The control device has a pressure increase control unit. When the pressure detection signal of the pressure switch indicates a high pressure, the pressure increase control unit estimates a pressure reduction N resulting from a fluid pressure consumption by a fluid pressure circuit. If the estimated amount of pressure reduction N exceeds a set value KN=KN1, KN2, the pressure increase control unit drives the pump for a set time KT=KT1, KT2, thereby ensuring a predetermined range of accumulator pressure despite a possible failure of the pressure switch or sensor.

Abstract: The device comprises: a flowstat 16 with a slider 16B with a built-in magnet 22 designed to interfere with a proximity-operated electric switch 20A; a variable-volume chamber 1 with a flexible wall 9 and spring means 28 that tend to reduce its volume; and a slider 26 combined with said flexible wall 9 and comprising a cam profile 30 acting on the movable slider 16B of the flowstat in the event of a drop in pressure in said chamber 1, in order to displace said slider 16B in the same direction in which the slider is displaced by the flow that passes through the flowstat; by this means the pump is actuated to restore the pressure in said chamber 1; whereas when the pressure in said chamber 1 drops further, owing to a lack of supply of liquid to the pump, the cam profile 30 ceases to act on the movable slider 16B and the pump stops.

Abstract: An automated control system for an engine-powered pump system. The pump system includes an engine with a battery and a pump. A control unit includes: a display, engine sensors, pump sensors, fluid level sensors, engine controllers, pump controllers, strobe light status display, and a battery recharge system.

Abstract: A pool pump controller includes a pneumatic pressure sensor having at least one port disposed to react to negative pressure within a pool's pump intake chamber. The sensor input port, which includes a check valve, is connected to a pump control switch through a pneumatic tube. The pump control switch combines aspects of a diaphragm switch and an opto-interrupter to provide high-reliability control of the pump motor in a watery environment.

Abstract: A fluid pressure control system which is usable to control pressure in a fluid distribution system includes a variable speed drive coupled to a pump. A hydropneumatic tank is coupled to the distribution system. In normal operation, the variable speed drive actuates the pump so as to maintain pressure in the system. Under low flow conditions, a control unit, using the variable speed drive energizes the pump so as to pump fluid into and pressurize the hydropneumatic tank. The control unit then shuts off the pump. Pressure is maintained in the system, until a predetermined, lower, set point is reached as a result of pressure in the hydropneumatic tank.

Abstract: An apparatus and method for monitoring and controlling a motor driven sump pump. The apparatus and method includes a power supply which powers the apparatus, a sensing portion which detects the level of the liquid within the sump, a control portion which turns the motor either off or on in response to the level of the liquid, and an alarm portion cooperating with the sensor which activates an alarm when a preselected level has been reached. The apparatus and method also includes power failure detection portion cooperating with the alarm portion which activates an alarm when a power failure occurs, a fault detection portion cooperating with the alarm portion which activates an alarm when the fault condition occurs, and a disabling portion which disables the pump when the fault detection portion detects a fault condition in the pump.

Abstract: An arrangement for regulating fluid conditioning stations including a plurality of pumping devices, at least one fluid storage reservoir, at least one pressure transducer and regulating mechanism, the conditioning station providing a fluid at a certain pressure and flow for consumption. The pumping devices start and stop such that the pressure in the fluid storage reservoir or reservoirs is maintained between two limit values of pressure (the start pressure and the stop pressure). Only one pumping device is started when the pressure in the storage reservoir(s) reaches or exceeds the value of the start pressure or when the flow provided by the pumping devices in operation is less than the consumption flow. Only one pumping device is stopped when the pressure in the storage reservoir(s) reaches the value of the stop pressure or when the flow provided by the pumping devices in operation is greater than the consumption flow.

Abstract: A suction-actuated control system (10) for a whirlpool bath/spa installation includes a suction-side transducer (52) connected in the suction inlet path and a controller (54). The suction-side transducer (52) transmits an air pulse to the controller (54) when pressure in the suction path drops below a pre-determined value caused, for example, by a full or partial blockage of a suction cover (26) by a wash cloth or an article of clothing. The controller (54) includes an electric switch (62) in circuit with the recirculation pump (34) and a bi-state controller (66) that actuates the electric switch (62) between its ON state and its OFF state. An abnormally low pressure in the suction path to the recirculation pump (34) caused by a full or partial blockage of the suction cover (26) will cause the controller (54) to shut-off the recirculation pump (34). After the obstruction is removed and a short time delay, the user can actuate a user ON/OFF control (56) to restart the pump (34).

Abstract: A fluid pressure system comprising an electric motor-driven pump for maintaining a predetermined pressure range in a system, including a remote solid-state encapsulated triac motor control circuit having a micro pressure sensor switch in the outlet duct from the pump. For example, this control device includes a special nipple for installation in a water well casing for maintaining a given range of water pressure in a system supplied by the well.

Abstract: An hydraulic actuator of a constant pressure fluidic supply system is disclosed in which a movable shuttle disposed within a generally cylindrical housing forms therewith a plurality of piston and cylinder assemblies. Displacement of the shuttle within the housing is governed substantially by opposing hydrodynamic and hydrostatic forces balanced so as to selectively isolate a pump control pressure switch from system pressure during periods of moderate to high consumption demand and provide communication therewith during periods of low to zero consumption demand. An hydropneumatic tank or a conventional diaphragm tank may be used in combination with the actuator to provide fluidic capacitance to the system. Additional system valving and pressure regulation may be incorporated as desired.

Abstract: An improved dual-stage pump system is provided for the accurate pumping and filtering of viscous fluids. Two hydraulically activated pumps are provided in series with a filter and reservoir disposed in-line between the two pumps. The reservoir acts as a source bottle for the second pump and allows the first pump to pump the viscous fluid through the filter at a rate independent of the dispensing rate of the second pump. By operating the first pump at a rate independent of the second pump, back pressure at the filter is avoided. Each hydraulically activated diaphragm pump is equipped with an improved diaphragm that is pre-formed to the geometries of the process fluid cavity thereby eliminating any inaccuracies in the operation of the pumps due to expansion of retraction of the diaphragm during pump operation.

Abstract: A device is provided for switching a submersible motor-driven pump on and off by a pressure sensor which measures the level of the liquid in the chamber enclosing the submersible motor-driven pump by the liquid pressure in the chamber, the pressure sensor being attached in or on the outside of the motor or pump casing and having a pressure-sensitive ohmic resistance.

Abstract: A power steering apparatus for turning a steerable wheel of a vehicle in response to steering operation by a driver. The apparatus comprises a hydraulic pump for pumping a fluid from a reservoir so as to supply pressurized fluid to a power cylinder formed in a gear housing through a direction control valve which is operable in response to rotation of the steering wheel for selectively delivering the pressurized fluid to pair of pressure chambers of the power cylinder. The apparatus further comprises an electric motor for rotating the hydraulic pump, an accumulator for accumulating the pressurized fluid discharged from the hydraulic pump, a detector for detecting the pressure of the pressurized fluid and for outputting a signal corresponding to the detected pressure, and a controller responsible to the signal from the detector for activating the electric motor only when the detected pressure is below a predetermined level. The hydraulic pump and the electric motor are mounted on the gear housing.

Abstract: A pressure switch adaptor designed to replace existing pressure switch adapters or connections and pressurizing air valves conventionally associated with water storage and distribution tanks. The adaptor is designed to be used as original equipment on new water tanks or to retrofit existing tanks, replacing the pressurizing air valve conventionally provided by the latter. Whether used on a new tank or retrofitting a used tank, the pressure switch adaptor fits into the port conventionally reserved for the pressurizing air valve. The adaptor provides a pressurizing air valve to allow initial pressurization of the air filled diaphragm and a pressure switch connection for fluid communication between an internal tank diaphragm and the pressure switch, which controls actuation of the tank's water-supplying pump. By placing the pressure switch adaptor on the air side of the system, problems associated with corrosion and corruption of the switch due to prolonged contact with water are eliminated.

Abstract: A pressure control loop apparatus for controlling the operation of an electromagnetic clutch in portable spray painting equipment powered by an internal combustion engine having a pressure transducer for sensing the pressure, a manually adjustable pressure reference, a comparator type error detector, and a pressure deadband control for inserting a deadband in the pressure control loop with the deadband varying as the pressure reference varies.