Abstract: A proportioner apparatus is capable of proportioning and admixing at least two liquids at relatively low pressures and minimizing waste of the liquids. The proportioner apparatus has a pressurizable reservoir for each liquid and a mix reservoir. The liquid reservoirs define an interior having a lower region. A fluid communication conduit provides fluid communication between the interior of the mix reservoir and the interior of the liquid reservoirs. A run-out conduit provides fluid communication between the lower region of at least one of the liquid reservoirs and the mix reservoir interior. When it is desired to run-out the liquid in the one liquid reservoir fluid flow from the one liquid reservoir through the fluid communication conduit is suspended and fluid flow through the run-out conduit is permitted.

Abstract: An automated chemical storage and chemical feed system for a use station to chemically treat and monitor a process at a use station where the process is being run, including one or more base chemical supply tanks at the use station storing chemicals and intermittently or continuously feeding the chemicals to the process. A level sensor is provided in each base tank to determine the chemical level and to deliver a signal to a control and processing unit. Sensors may be provided on the process for providing chemical condition information to the control and processing unit.

Abstract: A method and device for pumping a petroleum fluid passing through a pipe and having a quantity of gas and a quantity of liquid. The quantities of gas and liquid are measured to determine the weight of the fluid in a section of the pipe and, depending upon the relative quantities of the gas and liquid measured, an additional quantity of gas or liquid is added prior to the fluid containing the additional quantity being pumped. After the fluid has been pumped, the quantity of gas or liquid serving as the additional added quantity is sampled.

Abstract: An apparatus for combining fluids having a piston assembly which controls both the flow rate and the mixture ratio. The piston assembly is carried in a housing having two circular inlet ports and an outlet or mixing chamber. The housing and piston assembly also define first and second piston chambers. A first passageway permits the communication of the dominant gas port and the one piston chamber and a second passageway similarly permits the communication of the mixing chamber and the other piston chamber. The relative pressures in the first and second piston chambers influence the axial position of the piston which controls flow rate. Rotation of the piston controls the mixture ratio. A gate portion of the valve element attached to the piston stem is angled. The angled gate portion and circular inlet ports provide a progressive valving, which minimizes "hunting" of the apparatus when used with a control means in a feedback loop.

Abstract: A proportioner apparatus is capable of proportioning and admixing at least two liquids at relatively low pressures. The proportioner apparatus has a pressurizable reservoir for each liquid and a mix reservoir. A fluid communication conduit provides fluid communication between the interior of the mix reservoir and the interior of the liquid reservoirs. The liquid reservoirs are pressurized with a pressurizing gas to cause flow from the liquid reservoirs into the mix reservoir. A discharge conduit of the mix reservoir discharges admixture therefrom. When flow ceases in the discharge conduit the flow into the mix reservoir is also stopped as by shutoff valves in the fluid communication conduit. The proportioner apparatus can also include a pump operably associated with the discharge conduit to enhance admixture flow to a pressurizable tank that holds the admixture for further downstream processing. The pressure downstream of the pump is usually higher than the pressure upstream of the pump.

Abstract: For separating an oil and water mixture, the mixture is applied to the inlet of a cyclone separator so that the oil emerges from an overflow outlet and the water from an underflow outlet. Sensors measure the purity of the separated water and oil components and under control of a suitable control device, additions are made to the inlet liquid of quantities of oil or water to alter the ratio of oil and water quantities in the inlet mixture in a fashion tending to maintain separation efficiency. The oil and water to be admixed are taken from reservoirs.

Abstract: A method for continuously monitoring and/or controlling the cooling capacity of a liquid coolant containing gas bubbles. The method comprising the steps of: (a) measuring the size and number density of the gas bubbles it he liquid coolant by use of a sensor means to infer a heat transfer characteristic of the liquid coolant; and (b) varying the amount of gas that is being mixed with the liquid coolant so that the inferred heat transfer characteristic is within a predetermined range.

Abstract: The invention comtemplates preparation of glycol/water de-icing mixtures in a demand-operated system wherein index of refraction and temperature are continuously monitored in a recirculating loop. The supply of heat and changes in mixing proportions of separate flows of water and of glycol are monitored until such time as predetermined values of mixed-fluid temperture and refractive index are achieved. A computer accepts monitoring-signal values for mixed-fluid temperature and refractive index, and further accepts ambient-condition signal values for set-point variation in mixing proportions, as necessary for economical use of glycol in the mixture, under each of a plurality of different ambient conditions.

Abstract: A method for recirculating a high-temperature etching solution according to the present invention comprises the steps of continuously removing, from a bath for etching a wafer for a semiconductor device, a portion of an etching solution contained in the etching bath, injecting a predetermined amount of pure water for adjusting the concentration of the etching solution into the removed etching solution, heating the resulting solution to a predetermined temperature, and recirculating the heated solution into the etching bath.

Abstract: A mixing valve apparatus is disclosed, for producing a mixed fluid of a desired temperature obtained by mixing high temperature fluid and low temperature fluid with each other. The apparatus includes a pressure-sensitive control unit (6) which operates in response to the differential pressure (.DELTA.P) between the inlet pressure of the low temperature fluid and the pressure of the mixed fluid, and which unit controls the opening degree of an inlet valve (V.sub.1) for the high temperature fluid. Pilot passage (R.sub.0 .about.R.sub.3) for communicating the inlet pressure of the low temperature fluid to said unit is provided with a throttle (L, L.sub.1) whose effective surface area varies in response to the temperature of the mixed fluid, to compensate the opening degree of the inlet valve (V.sub.1) for the high temperature fluid upon variation of the temperature of the mixed fluid.

Abstract: In the fluid mixing fixture, a displacement body and a tubular shell, which coaxially encloses the displacement body, are arranged at an inflow element. A temperature measuring element, such as a nickel wire which is covered by a plastic jacket, is wound around the tubular shell at the region of an annular gap formed between the displacement body and the tubular shell. Hot water and cold water flow through inflow openings of the inflow element and into a recess or chamber thereof, at that location the hot water and cold water are admixed and then the admixed water flows through the annular gap to an outflow opening. Since the flow cross-sectional area of the annular gap is smaller than the inflow cross-sectional area of the inflow openings the velocity of the admixed water is increased. This promotes further admixing of the hot and cold water and enhances heat transfer to the tubular shell.

Abstract: A system for blending low and high octane gasoline includes independent flow paths for each fuel between a supply source and a composite blend manifold and nozzle assembly, with the rate of flow of fuel in each flow path being under individual closed loop control, under an algorithm for comparing the ratio of the actual accumulated volumes of the low octane to the high octane fuel, relative to a statistically determined ratio of the ideal volume of said low to high octane fuel for the total actual accumulated volume of the sum of the volumes of the fuels at a given time, for providing a perfect blend relative to a preselected blend ratio.

Abstract: A method for measuring liquid to be transferred from a container or containers to a measurement pot includes the steps of: determining an initial degree of opening of the valve for controlling flow-rate of the liquid from the container to the pot based on the valve's flow-rate characteristics and an arbitrarily chosen set value; opening the valve by the initial degree of opening; detecting the actual amount of liquid that has flowed into the pot; determining a next degree of opening of the valve based on the actual measurement and the set value; and changing the degree of opening of the valve to the next degree of opening. The determination of the degrees of opening of the valve is based on fuzzy control, which uses a fuzzy inference from the set value and actual measured value. An apparatus for measuring liquid for use in a liquid mixing apparatus uses the above-mentioned method.

Abstract: A pilot operated flow modulating control valve assembly with a pilot valve to initiate opening and closing of a main control valve, and a secondary valve for separately controlling pressure across the control valve to achieve its modulated positions.

Abstract: A measuring mixer for use with either liquids or powders in which different supply systems supply different stock liquids or powders to a receiving container from supply containers. A continuously variable flow regulator is associated with each supply container. The cumulative weight of the receiving container is measured and compared with a target weight. Then a computation section calculates a desired flow rate based upon both the deviation from the target weight and a time variation thereof. This calculation is preferably done according to fuzzy inference. The desired flow rate is then used to control a selected one of the flow regulators so that the measurement is sequentially performed between supply systems. Optionally, the receiving container can be movable between the different supply systems.

Abstract: N.sub.2 and CO.sub.2 are admitted, through separate valves actuated by single high hysteresis actuator, into a mixing device when the mixture is fed to a beer keg. The actuator is dependant upon the relative Co.sub.2 N.sub.2 mixture pressures so as to maintain the mixture pressure within predetermined limits and in one embodiment the use of a venturi mixing device ensures that the mixture composition remains substantially constant when the N.sub.2 and CO.sub.2 gases are at substantially different pressure.

Abstract: An apparatus for automatically metering gas into liquid comprises a gas sly line including a gas pressure regulator (1), a gas flow meter (2), a gas flow governor (3), a vacuum check valve, and an ejector (5) connected to a supply line of the liquid being gasified, a liquid flow meter (9), and a control system (39). The gas flow governor (3) and the vacuum check valve are integrated in a single unit including a sealed chamber (11) whose two opposite walls are defined by diaphragms (12,13), a hollow cylinder (14) disposed between the diaphragms and having a central opening (17) through one its face end, a sleeve (19) with a closed end, mounted coaxially with the hollow cylinder centrally of a diaphragm (13), its closed end being fixedly connected with an output element (26) of the gas flow governor (3), and a needle valve with a valve with a valve seat (2) and a valve member including a stem (22) with a pointed tip (23 ) on its one end, extending axially of the hollow cylinder.

Abstract: A system for preparing a fluid intended for a medical procedure substantially at the time of use by mixing of at least one concentrate in powder form with water. The system includes a reservoir for a source of water, at least one vessel containing a concentrate in powder form and a concentrate fluid circuit for withdrawing a small quantity of water from the reservoir and passing same through the vessel containing the concentrate in powder form in order to dissolve the concentrate to produce a concentrate fluid, and for then conducting the concentrate fluid to a primary fluid circuit communicating with the reservoir so that the produced concentrate fluid is mixed with the rest of the water withdrawn from the reservoir. In a preferred embodiment, the vessel comprises a self-contained cartridge containing a quantity of concentrate in powder form therein which is suitable for one treatment procedure.

Abstract: A method and apparatus for controlling the gas content of dispensed hot melt thermoplastic adhesive foam. Air or another relatively inert gas is mixed with molten thermoplastic adhesive, and the mixture is pressurized to form a gas and molten adhesive "solution". When the molten adhesive and gas "solution" is dispensed at atmospheric pressure, the gas is released from "solution" and becomes entrapped in the adhesive in order to form a homogeneous closed cellular adhesive foam. In order to control the gas content of the dispensed adhesive and gas "solution", in accordance with one preferred embodiment, the pressure drop across a restriction in the flow path of the solution is sensed, and a control circuit controls the addition of gas to the adhesive to maintain the sensed pressure drop at a desired level.

Abstract: A control system is provided which can be retrofit to existing conventional blender devices, such as a blender trailer used for combining a pregelled liquid with a solid particulate additive at a well site. The control is provided either manually or automatically from a remote location where a display unit and a computer unit of the invention are located, such as in a frac van. The display unit and the computer unit are connected together by a multi-conductor cable, and the display unit is connected by a multi-conductor cable to a terminal unit mounted on the blender. Control signals are output from the display unit, under automatic control by the computer unit or under manual control by potentiometers attached to the display unit, to control electrohydraulic valves associated with screw conveyors mounted on the blender.

Abstract: An apparatus for combining fluids having a piston assembly which controls both the flow rate and the mixture ratio. The piston assembly is carried in a housing having two inlet ports and an outlet port or mixing chamber. The housing and piston assembly also define first and second piston chambers. A first passageway permits the communication of the dominate gas port and the one piston chamber and a second passageway similarly permits the communication of the mixing chamber and the another piston chamber. The relative pressures in the first and second piston chambers influences the axial position of the piston which controls flow rate. Rotation of the piston controls mixture ratio.

Abstract: A method and apparatus for controlling the density of a foam. The method involves measuring the electrical conductivity of a foam wherein the electrical conductivity of the foam varies with the density thereof and adjusting the density of the foam in response to the measured electrical conductivity to prepare a foam having a desired density. The apparatus comprises means for generating and applying a foam, said means being connected by an enclosed pathway. Located within the enclosed pathway is an electrical conductivity sensor. The conductivity sensor is electronically connected to a translation means. The conductivity sensor provides an electrical signal, related to conductivity of the foam, to the translation means. The translation means is connected to a gas flow controlling means.

Abstract: A system for dispensing and controlling the concentrate of a juice product in which the product is made up of a juice concentrate and water. The concentrate is dispensed by pump operation and the water is dispensed by solenoid operation. The system basically provides for the control of the solenoid and the pump and for the initiation of a dispensing cycle so as to initiate operation of the solenoid and pump substantially at the same time. A timer responds for operating the solenoid and pump over a preselected dispensing period. The control of the pump to provide concentration control is provided by a speed control circuit having multiple selectable positions for providing multiple pump speeds so as to in turn provide variable concentration of the final dispensed juice product.

Abstract: In a method for control of a sanitary mixer for cold and hot water, merely the actual temperature is continuously measured in the mixed water and compared to a preset temperature. At least two separate, time-varying regulating values, used for electromechanical adjustment both of the cold as well as of the hot water supply, are electronically derived from the difference between the set and actual temperature. A preset flow rate of the mixed water that is to be kept constant during temperature control is taken into account in the determination of the regulating values. Furthermore, partial flow rates for the cold water supply and hot water supply that are proportional to the regulating values can be determined from the time-varying regulating values. These are then used to continuously determine the instantaneous cumulative filling volume of the mixed water. As soon as a cumulative filling volume value equal to a preset cumulative filling volume is reached, the cold and hot water supplies can be shut off.

Abstract: A polymer feed system comprises at least one mixing and activating apparatus having a water inlet, a polymer inlet and an outlet and constructed and arranged to dilute and fully activate a polymer. The polymer feed system further comprises a conduit for carrying water to the water inlet of the mixing and activating apparatus. A conduit is coupled between the outlet of the mixing and activating apparatus and the first conduit. Activated polymer merges with the remainder of the water and is mixed in a static mixer.

Abstract: A feed device for a two-phase fluid pump enabling the pump to be supplied with a two-phase fluid having characteristics, especially the volumetric ratio of the gaseous phase to the liquid phase, compatible with the operating characteristics of the pump. The device has a main pipe (10a) and a plurality of auxiliary pipes (10b, . . . 10i) parallel to the main pipe. Each of the pipes can be connected to an upstream supply line of two-phase fluid, and to the downstream pump (6), each of the pipes having an isolation and flow regulating gate (11a, . . . 11i) at its upstream inlet and an isolation and flow regulating gate (12a, . . . 12i) at its downstream outlet, each of the pipes also having means (16a, . . . 16i; 17a; 17i) for introducing a carrier liquid, such as water.

Abstract: A system for automatically dispensing stock solutions is disclosed, comprising a dispenser, pipette keeping and washing units and a control unit. The respective pipette keeping and washing units have different types of pipettes. First, the control unit selects the most appropriate pipette according to the type and amount of mixture of stock solutions to be prepared. The dispenser then receives the selected pipette from the corresponding pipette keeping and washing unit and is detachably fitted with the appropriate pipette to feed a predetermined amount of stock solution into a receptacle by manipulating the pipette. Having finished dispensing, the dispenser transfers the used pipette back to the corresponding pipette keeping and washing unit. On completion of the transfer, the control unit causes the pipette keeping and washing unit to wash the transferred pipette.

Abstract: The gaseous CO.sub.2 is supplied at a pressure of 10 bars and at a constant rate of flow to the primary inlet (3) of an aspiration device (1). Gaseous SO.sub.2 coming from a cylinder (24) which is heated and contains liquid SO.sub.2 is conducted through a heated line (4) provided with an adjustable flow meter (27) to the secondary inlet (5) of the aspiration device. The mixture issuing from the latter is injected into a buffer tank (6) whose pressure is regulated at a value higher than the pressure of utilization and is drawn from this buffer tank when utilized. Applications in the supplying of mixtures for hardening sand moulds or cores to foundries of medium size.

Abstract: A method and apparatus for monitoring the rate of addition of an additive fluid that is to be added to a main fluid stream in a gas pipeline system. A monitoring interval is defined by selecting a base measurement parameter, and the flow rate of the main gas stream and of the additive fluid are measured during the monitoring interval. The average ratio of additive fluid flow to the main gas stream flow during the monitoring interval is calculated by a data logger, that displays and records the result and the date and time of day that the ratio calculation is made. The monitoring intervals can be defined by a predetermined quantity of odorant flow, a predetermined quantity of main gas flow, or a particular period of time.

Abstract: A gas flow control system for an anesthesia apparatus, which has an oxygen gas pressure reducing valve for reducing primary pressure of oxygen gas to secondary pressure, and a anesthetic gas pressure reducing valve for reducing primary pressure of anesthetic gas to secondary pressure. A pressure control valve is connected to the secondary side of the anesthetic gas pressure reducing valve and responsive to the secondary pressure of the oxygen gas for controlling the secondary pressure of the anesthetic gas. The pressure control valve is so arranged that when the secondary pressure of the oxygen gas is zero, the pressure control valve is closed to cut off the supply of the anesthetic gas.

Abstract: A gas blending system includes a proportional mixing valve having a valve element movable between first and second limits of travel corresponding to a minimum and maximum percentage, respectively, of one of the gases in the blended mixture. The position of the valve element is detected by a detection mechanism, producing a position signal inputted to a microcomputer. The microcomputer also receives a control signal representing a desired percentage of one of the gases to be blended. The microcomputer calculates a desired valving element position as a function of the value of the control signal, and generates a drive signal as a function of a comparison made by the microcomputer between the detected valve element position and the desired position. A motor drives the valve element to the desired position in response to the drive signal.

Abstract: A portable apparatus for controlling the production of a mixture of a fluid and a plurality of additives utilizes a unified control panel having all of the necessary controls compactly contained in a single housing for providing both automatic and manual control of each of the additive channels through which the additives are mixed with the primary fluid. The control of each additive channel is achieved through a software controlled algorithm by which errors are only incrementally, rather than totally, applied to prior drive signals at any one time.

Abstract: A self-contained portable unit for producing a mixture of substances in response to two separate flows includes a portable trailer upon which a holding tank is mounted. Various additive channels are maintained on the trailer for introducing additives, at selectable concentrations or rates, into a first flow which occurs through an inlet conduit connected to an input of the holding tank. Connected to an output of the holding tank is an outlet conduit to which an external blender device can be connected. The trailer has additional additive channels contained thereon for introducing further additives, at selectable concentrations or rates, into a second flow between the holding tank and the external device. Control of the additives is maintained by a microcomputer-based controller or a manual, back-up controller, whichever is switchably selected for each additive channel.

Abstract: A method of mixing a plurality of gases in a specified proportion and dosing the resultant gas mixture comprises supplying individually controlled gas streams from suitable sources thereof in a pulse-like fashion to an enclosed chamber from where the resultant gas mixture can be delivered to a point of use, such as a patient undergoing anesthesiological or respirational treatment.Each gas source is connected, via feed lines each having a back-pressure valve and an on-off solenoid valve, via a common flow line to an enclosed mixing chamber. A first and, optionally, a second flow meter are operationally positioned between the common flow line and the enclosed mixing chamber and generate electrical signals in accordance with select properties of the gas streams passing through such flow meter. These signals are transmitted to a microprocessor-controlled regulating unit, which also controls the solenoid valves in accordance with a specified program to provide desired gas pulses to the enclosed mixing chamber.

Abstract: A control system for blending a rich stream with a diluting stream to obtain a blended stream comprises obtaining values for specific gravities of the rich and diluted streams, a ratio of densities of primary and secondary components in the rich stream and value corresponding to the concentration of primary component in the rich and the blended streams. Additional elements are utilized to obtain actual volumetric flow rates for the rich stream as well as the specific gravity of water in the rich stream and the diluting stream. An algorithm is utilized to manipulate the foregoing values and obtain a desired value for the diluting stream volumetric flow rate and control the flow rate accordingly.

Abstract: A control system (10) is provided for maintaining a constant fluid level in a mixing container of a delivery and metering device. Structure (12) is provided for monitoring the fluid level in the mixing container and for generating a level signal (14) representing the fluid level present in the mixing container. Structure (18) is further provided for establishing a desired amount of fluid entering the mixing container and for generating a first control signal (20). Structure (22) is provided for establishing a desired amount of fluid discharged from the mixing container and for generating a second control signal (24). Measuring devices (30, 34) are utilized for measuring the amount of fluid discharged from the mixing container and for generating a discharge signal (36) representing the amount of fluid discharged from the mixing container.

Abstract: A process for heating fluids to a relatively high temperature, such as sterilization temperature, in which the fluid, such as a liquid, is heated by direct contact with steam while it is in the form of a very thin, free-falling film or a continuous falling stream so that heating of the fluid is accomplished without the fluid coming into contact with any surface and particularly metal surfaces which are hotter than the fluid product being heated and with minimum agitation and turbulence of the fluid product. This procedure enables maximum and uniform heat penetration in a minimum time interval with the film or stream being maintained as thin as possible and unbroken by introducing steam at a relatively low velocity in a large volume vessel.

Abstract: A gas-liquid blender (30) is provided for metering a liquid into the controlled flow of gas. The blender (30) includes a gas inlet (32), an outlet (42), a variable proportioning device or mixing valve (38) between the gas inlet (32) and outlet (42), and a liquid inlet (36) to the variable proportioning device (38). A diaphragm controlled servo positioning valve (44) is disposed between the gas inlet (32) and the variable proportioning device (38) and is opened and positioned by a diaphragm controlled throttle valve (58) which differentially senses liquid pressure and gas pressure to the variable proportioning device (38). Adjustment means (102, 104) are provided for the throttle valve (58) to increase the pressure difference across the liquid leg of the variable proportioning device (38) between the liquid inlet (36) and the outlet (42) without increasing the pressure difference across the gas leg of the variable proportioning device (38).

Abstract: In a process in which a fuel gas stream having a high BTU content is mixed with a fuel gas stream having a low BTU content to form a mixed fuel gas stream, the flow rate of the high BTU content fuel gas stream is manipulated to maintain a desired BTU content for the mixed fuel gas stream unless such control based on the desired BTU content for the mixed fuel gas stream would result in condensation in the mixed fuel gas stream. If condensation would occur, then the flow rate of the high BTU content fuel gas stream is manipulated so as to maintain the actual dew point temperature of the mixed fuel gas stream below the actual temperature of the mixed fuel gas stream to prevent condensation.

Abstract: A mixing valve arrangement for producing temperature controlled water wherein an electromagnetically actuatable supply valve is coupled in each of the hot and cold water supply lines is described. Electronic control loop circuits generate a temperature control signal from both a temperature preselector and a temperature detector and a volume control signal from both a volume preselector and a mixed water flow volume detector. An electronic decoupling circuit is interposed between the two control loop circuits and the valve actuating circuits to derive control signals representative of the degree of opening of the two supply valves from the temperature and volume control signals.

Abstract: An apparatus for introducing powdered solids into a liquid stream at a controlled rate to form a slurry. Solids are metered to an eductor where they are educted into the liquid stream. An automatic cycle timer-controller purges eductor, hopper and piping of residual solids before solids flow is initiated, and following solids flow. Pressure sensors detect low water pressure and/or plugging, shutting off liquid and solids flow.

Abstract: In an installation for treating workpieces by a glow discharge in a mixture of gases, the gas pressure is detected and valves for the various gases are cyclically and symmetrically opened and closed by amounts relative to the volumetric ratio of the gases.

Abstract: In anesthesia apparatus for supplying oxygen and an anesthesia gas through respective flow control valves to a patient breathing circuit an oxygen flow ratio controller is provided. The system includes a restrictor in the pipeline of the oxygen flow control valve and a restrictor in the pipeline of the anesthesia gas flow control valve. The oxygen flow ratio controller includes differential pressure sensing means and anesthesia gas flow control means, the differential pressure sensing means includes a diaphragm assembly responsive to the pressure in the oxygen pipeline and another diaphragm assembly responsive to the pressure in the anesthesia gas pipeline and is coupled to the restrictor pipelines. The anesthesia gas flow control means controls the flow of gas to the anesthesia gas pipeline. The diaphragm assemblies are opposed to each other and are coupled together by a displaceable linkage.

Abstract: A fluid mixer includes a porous foam disc for dispersing fluid flowing therethrough, an inlet disc adjacent one surface of the porous disc for limiting the area of the latter through which fluid may enter the same, an outlet disc proximate an opposite side of the porous disc for limiting the area of the latter at which fluid may leave the same, with the radial location of the inlet area being different from that of the outlet area to obtain dispersed fluid flow through the foam disc. Other features include a fluid orifice assembly using an orifice housing held in fluid-tight relation to a fluid fitting by a radially applied force; and a differential pressure responsive mixing control valve for controlling flow of one fluid into a mixing chamber to which another fluid also is delivered.

Abstract: A system for injecting chemicals into a fire fighting system of the type using a plurality of water hoses and having a source of water and a source of chemicals. A servo motor system is connected to automatically meter a certain ratio of chemicals into the water supply. The servo motor system is responsive to the total flow to control the chemical pump to pump a certain ratio of chemicals into the water supply even if the total flow varies. Various modifications are disclosed.

Abstract: This invention concerns a multi-liquid flow proportioning device comprising a vessel adapted to contain a first liquid, a container within said vessel adapted to hold a second liquid separate from said first liquid, separate inlet and outlet means respectively for the portion of said vessel adapted to contain said first liquid and for said container, said container including a wall portion adapted to move in use in resopnse to changes in pressure of its liquid contents, and means operable by the movement of said wall portion to control the liquid flow into the inlet of said container whereby tending to maintain the volumetric contents thereof generally constant. The invention has particular application to combining water and fire retardant.

Abstract: An apparatus for heating fluids to a relatively high temperature, such as sterilization temperature, in which the fluid, such as a liquid, is heated by direct contact with steam while it is in the form of a very thin, free-falling film or a continuous falling stream so that heating of the fluid is accomplished without the fluid coming into contact with any surface and particularly metal surfaces which are hotter than the fluid product being heated and with minimum agitation and turbulence of the fluid product. This procedure enables maximum and uniform heat penetration in a minimum time interval with the film or stream being maintained as thin as possible and unbroken by introducing steam at a relatively low velocity in a large volume vessel.

Abstract: Apparatus for combining fluid flows in variable proportions is adapted for blending an active constituent gas and a diluent gas to calibrate gas analyzers used in monitoring pollution.Diluent gas passes from source 34 through a downstream differential pressure regulator 17 and a constant flow restrictor 12 to outlet 14 which communicates with control port 20 of regulator 17. Active gas passes from source 35 through differential pressure regulator 23, through three fixed parallel flow restrictors 22, 29 and 30 to combine with the diluent gas upstream of restrictor 12. Control port 26 of regulator 23 communicates with the input to restrictor 12. Switching of valves 31, 32 and 33 varies the rate of flow along conduit 16 and hence the proportions of gases combined upstream of restrictor 12. Regulator 23 maintains flow along 16 substantially constant for given valve settings, and regulator 17 maintains flow along outlet 14 substantially constant despite changes in flow rate in the conduit 16.

Abstract: An apparatus for the controlled proportioning of gases to be delivered to a consumer comprises a mixed gas line containing the mixed gases to be delivered to the consumer which is connected to a plurality of separate gas supply lines. Each of the supply lines includes a quick-acting, electrically controlled valve which is controlled by control means which is effective to deliver a control pulse to open and close the valve in accordance with a set time slot pattern. For this purpose, the controller advantageously includes means for sensing the pressure in each of the supply lines and the mixed gas line and for regulating the quick-acting valves in accordance with one or more input signals which are fed to a computer section of a controller which has an actuator section which is operated in accordance with the sensed information and the input signals to carry out the supply of the gases in the set time slot pattern.

Abstract: A process for heating fluids to a relatively high temperature, such as sterilization temperature, in which the fluid, such as a liquid, is heated by direct contact with steam while it is in the form of a very thin, free-falling film or a continuous falling stream so that heating of the fluid is accomplished without the fluid coming into contact with any surface and particularly metal surfaces which are hotter than the fluid product being heated and with minimum agitation and turbulence of the fluid product. This procedure enables maximum and uniform heat penetration in a minimum time interval with the film or stream being maintained as thin as possible and unbroken by introducing steam at a relatively low velocity in a large volume vessel.