Abstract: A spray generator for producing a spray of liquid droplets of a narrow size spectrum in which a substantially uniform cyclic disturbance is imposed on fluid energing at a nozzle. Such a disturbance can be produced by a fluidic bistable oscillator or by allowing the fluid to flow across a bluff body in the flow path. An opposed jet arrangement can be located within the vortex chamber of a fluidic diode and the liquid spray produced can meet swirling gas introduced at tangential inlets to the chamber.

Abstract: A fluidic oscillating nozzle that oscillates a fluid jet at high frequency by the use of fluidic amplification technology with no moving parts. The jet that issues from the nozzle is a zero-degree jet of fluid that maintains a very high energy density; however, due to its oscillation, its appearance is that of a fan-type jet that disperses at a fan angle from the nozzle. At a nominal distance from the nozzle, the jet covers the surface with a relatively broad area of flow while maintaining high energy impact density due to the impact effects of the non-expanding zero-degree jet.

Abstract: An enhanced output opto-fluidic device includes three plates which together bound a number of passages including an interaction passage, an inlet channel including which opens into one of such ends, and two outlet channels which open into the other end of the interaction passage at symmetrically arranged outlet regions. Fluid is caused to flow through the inlet channel into the interaction passage to form a jet stream that flows toward the outlet regions.

Abstract: A fluidic-oscillator type flowmeter has an inlet nozzle (1) leading into a chamber (2) with diverging side walls (3a, 3b). A splitter (8) has a blunt end opposite the inlet nozzle and defines outlet paths (4a, 4b) which lead from the chamber. The shape and position of the splitter are such that oscillating flow is encouraged across its face. Feedback channels (5a, 5b) lead from the side walls back to control ports (7a, 7b) which open into the chamber. The relative position of the splitter and feedback channel entrances is such that the downstream corners of the entrances to the feedback channels lie in the oscillating path of the edge of the flow which separates from the face of the splitter when the meter is in use.

Abstract: A fluidic set point amplifier provides an output signal which is strongly linear with respect to pressure of fluid supply, free of hysteresis, and has a zero crossing (set point) at a determined value of supply pressure. Uses of the set point amplifier include an all-fluidic pressure regulator, and a turbine engine fuel control having only a single moving part.

Abstract: For removal of the contaminant deposits from a surface such as a tube sheet of a vertical tube heat exchanger, as in a nuclear steam generator, having plural spaced heat exchange tubes connected to the tube sheet, a lance is radially moved along the tube sheet between parallel rows of tubes. The lance carries a nozzle for ejecting a stream of high pressure cleaning fluid toward the sludge deposits, the nozzle acting cyclically to sweep the stream throughout a range of directions centered about the nozzle axis. The nozzle may include diverting streams for deflecting the cleaning fluid stream, with the diverting streams either being generated by a fluidic oscillator or being fed back from the outlet portion of the nozzle. Alternatively, pivoting vane means may be provided in the nozzle to divert the cleaning fluid stream.

Abstract: A modified laminar proportional amplifier with feedback for converting the absolute pressure of a pressurized fluid to a differential pressure indicating the pressure of the pressurized fluid relative to a predetermined set-point pressure. The device includes two outlets separated by a splitter, a supply nozzle for directing a jet of the pressurized fluid toward a first of the two outlets at a velocity determined by the absolute pressure and a feedback path for deflecting the jet toward the second outlet such that as the jet increases to a maximum value and then decreases until the differential pressure between the two outlets is equal to zero when the absolute pressure of the pressurized fluid is equal to the predetermined set-point pressure. The feedback path includes an adjustable fluidic resistor and a temperature compensated flow controller for making the device insensitive to temperature.

Abstract: A fluidic complementary gain changing circuit has three laminar proportio amplifiers, one of which supplies fluid pressure streams to the other two. The latter amplifiers have substantially identical geometries and complementary gain curves at any given supply pressure, relative to a gain changing signal constituting a bias pressure applied to control ports of the first amplifier. A differential input signal supplied to the control ports of the two complementary amplifiers modulates the supply streams traversing those amplifiers and results in concurrent high and low gain complementary signals at the respective outlet ports of the overall circuit. Variable resistance elements permit calibration of the circuit.

Abstract: An invention is disclosed in which a fluidic counter generates fluidic switching signals in response to a fluidic oscillator for sequentially activating a plurality of fluidically activated electrical switches for multiplexing a plurality of electrical conductors into a single conductor.

Abstract: The invention relates to fluidic transducers of electrical signals from an electronic computer for accurately metering flow of a liquid to a utilization device. A liquid filled hollow channel means is accelerated along the flow axis thereof to produce a fluid control signal for a bistable fluidic switch element having a pressurized, cross-over type interaction region leading to a common outlet and to a pair of output passageways. In a preferred embodiment, electrical signals from an electronic computer are supplied to a coil centered by a spring in a magnetic field, first in one direction of current flow and then in the opposite direction, to introduce bidirectional movement of the coil and the hollow channel means coupled thereto. The signals are preferably frequency modulated (but may be pulse width modulated).

Abstract: There is disclosed a fluidic oscillator in which a stream of fluid is directed against a barrier member in an oscillation chamber. The barrier member serves as one wall of the oscillation chamber and in conjunction with other shaped wall surfaces of the oscillation chamber creates a pair of alternately pulsating control vortices for causing the fluid in the power stream to pass alternately to a pair of outlet passages. The vortices alternate both in strength and in a phase opposition to control flow of the jet stream in alternate fashion through the outlet passages. In a preferred embodiment of the invention, the pair of outlet passages are on opposite sides of the barrier member and converge to a common outlet to thereby provide a fan spray as the outlet passages alternate in the passage of the stream of fluid therethrough to the common outlet.

Abstract: A method and apparatus for converting the absolute pressure of a pressuri fluid to a differential pressure indicating the fluid pressure relative to a reference pressure. The pressurized fluid is directed asymmetrically into a laminar proportional amplifier (LPA) along a centerline toward a first of two outlets at a velocity determined by the fluid pressure. The LPA includes first and second control inlets disposed on opposite sides of the directed fluid jet and connected to a common source of control fluid, the first control inlet being disposed on the same side as the first outlet, and the second control inlet being disposed on the same side as the second outlet.

Abstract: A turbine engine fuel measuring and control system which incorporates a fluidic density sensor which is unaffected by variations in the physical characteristics of the fuel supplied to the engine.

Abstract: The liquid spray includes an oscillator for producing a fan spray with liquid droplets of uniform size. The oscillator is constituted by a power nozzle, a pair of side walls forming a pair of vortice spaces offset from the power nozzle, a pair of inwardly extending protuberances or deflectors downstream of which are a pair of inlets to passages leading to exits adjacent the power nozzle, and an outlet throat or aperture having a pair of short wall surfaces defining an exit throat of any value selected from about 30.degree. to about 160.degree. so that the fan angle can be selected to be from about 30.degree. to 160.degree.. This structure results in an oscillator which has a relatively low threshold of pressure at which oscillations are initiated and, most importantly, the liquid is issued in a much more uniform fan pattern than heretofore possible.

Abstract: The process of removing embedded particulates from the pore surfaces of an ngine air cleaner (pleated paper type) is facilitated by blowing pulses (or jets) of compressed air through the filter media in the reverse flow direction. The invention relates to the employment of a fluidic oscillator for producing the air pulses. The oscillator is used in a switching mode such that alternate pulses are applied to different air cleaner sections. Overall objective is to achieve an effective cleaning action with a relatively small quantity of compressed air.

Abstract: A broad band flueric amplifier is disclosed which comprises means to incre the deflection of the fluid jet within the amplifier at higher frequencies of oscillation of the jet. The means for increasing jet deflection comprises vanes or protrusions positioned closely adjacent the jet path at selected distances from the nozzle. Acoustic feedback from these vanes or protrusions will assist the control pulse in deflecting the jet at selected frequencies of oscillation.

Abstract: A telemetry system is disclosed which utilizes a fluid feedback oscillator n conjunction with a flow restricting device in order to generate pulses in a fluid. Means are provided to turn the oscillator on or off or to vary the frequency of oscillation, thereby permitting the transmission of information by means of the fluid pulses.

Abstract: A temperature compensation device for a fluidic circuit is disclosed. The vice comprises a high gain fluid amplifier having input and feedback resistors. The resistance to fluid flow through the input resistor is dependent upon fluid density, while the resistance to flow through the feedback resistor is dependent upon fluid viscosity.

Abstract: The fluidic oscillator consists of a resonant fluid circuit having a fluid inertance and a dynamic fluid compliance. The inertance is a conduit interconnecting two locations of a chamber on each side of a working fluid jet issuing into one end of the chamber, the inertance conduit serving to transfer working fluid between the two locations. Through one or more output orifices located approximately at the opposite end of the chamber, the fluid exits from a chamber exit region which is shaped to facilitate formation of a vortex (the dynamic compliance) from the entering fluid. The flow pattern in the chamber and particularly the vortex in the chamber exit region provide flow aspiration on one side and surplus of flow on the opposite side of the chamber, which effects accelerate and respectively decelerate the fluid in the inertance conduit such as to cause reversal of the vortex after a time delay given by the inertance.

Abstract: In a clothes washer, liquid pulses are delivered to a bucket or tank of water to create continuously recirculating flow therein in a vertical plane. The flow carries the clothes in a tumbling action and the pulses agitate the clothes passing the pulse source. Air is introduced into the water pulses and forms air bubbles in the tank which attract dirt particles and carry them to the surface where they are removed as part of a continuous surface overflow. In a preferred embodiment the liquid pulses are delivered by a novel fluidic oscillator of the feedback type in which air is continuously entrained by the power stream from each feedback passage in alternation. In one form, the oscillator utilizes scoop-type feedback passages between respective outlet passages and control ports, each feedback passage communicating with an air passage.

Abstract: The temperature sensors shown utilize a constant frequency fluidic oscillr to excite resonance tubes, whose frequency response is a function of temperature. The outputs of these sensors control a fluidic amplifier, whose output is rectified and filtered to produce a D.C. fluid signal which is a function of the sensed temperature. Different embodiments utilize resonance tubes excited in phase or 180.degree. out of phase to sense the difference between two temperatures or to provide increased sensitivity.

Abstract: This invention relates to a flow meter of a fluidistor oscillator type, which has its principal use when measuring the ventilation of a moving human being or animal. Thanks to the special design of the flow meter it can be made small, light and portable at the same time as the pressure drop in it is minimal.

Abstract: A flow meter comprising a fluidic switching device coupled as a free-running oscillator. The frequency is dependent on the flow rate of the medium. The device called a fluidistor has a nozzle (edges) arranged upstream of the control chambers and a first region downstream of the control chambers, within which first region the flow of medium lies either on one side or the other side in dependence upon the pressure conditions and flow conditions prevailing in the oscillator circuit. A second region is located downstream of said first region. Mutually spaced apart orifices of a cross-connecting line, said orifices preferably being arranged transversely to the flow direction, are arranged at a location at which the stream of fluid is deflected, in a manner such that said orifices are coupled together, through a line. In said line is a pressure-sensing device arranged to generate a signal corresponding to the measuring result and that said deflection location is placed downstream of the control chambers.

Abstract: A windshield washer comprises a nozzle in which a liquid jet is formed and repetitively transversely swept before egressing from the nozzle body. The swept jet breaks up into liquid droplets which impinge upon a wide area of a windshield. In a preferred embodiment the nozzle is an oscillator, preferably a fluidic oscillator, in which the jet is swept oscillatorily between two extreme positions. In still another form of the invention discrete slugs of liquid are alternately issued in at least two directions from a common nozzle body.

Abstract: A fluid dispersal device utilizes the Karman Vortex street phenomenon to cyclically oscillate a fluid stream before issuing the stream in a desired flow pattern. A chamber includes an inlet and outlet with an obstacle or island disposed therebetween to establish the vortex street. The vortex street causes the stream to be cyclically swept transversely of its flow direction in a manner largely determined by the size and shape of the obstacle relative to the inlet and outlet, the spacing between the obstacle and the outlet, the outlet area, and the Reynolds number of the stream.

Abstract: In order to determine the constituent gases of a gas mixture, the test gas is employed as the working fluid for an astable fluidic oscillator in a series of runs taken at different temperatures. The pulse repetition frequencies observed are related to similar pulse repetition frequencies observed when air is employed as the working fluid at corresponding temperatures and pressures. By this means, a plurality of equations can be written and solved for the unknown percentages. The characteristics of a given astable multivibrator can readily be predetermined and recorded on a graph in a table to facilitate preparation of equations which can be solved by ordinary simultaneous equation techniques.

Abstract: A breathing apparatus primarily intended to be used in administering oxygen to a patient can be constructed so as to utilize a fluidic control device in such a manner as to conserve oxygen. The control device is connected to a supply of the gas to be administered to the user, to a reservoir type structure for temporarily storing this gas and a respiration structure such as a connected pair of tubes adapted to extend loosely into the nostrils of the user. On inhalation through the respiration structure the control device serves to permit gas flow from both the supply and the reservoir type structure to the respiration structure and to the user while on exhalation by the user the control device is responsive to the pressure exerted by the flow of exhaled gas in order to cause gas flow from the supply to the reservoir type structure.

Abstract: A liquid spray is characterized by a liquid jet which is cyclically deflected at a high frequency such that it breaks up into a fan-shaped spray pattern in which the fluid distribution and droplet size can be controlled. Jet deflection is accomplished with energy in the pressurized liquid itself. In a preferred embodiment, the spray is produced by a fluidic oscillator, of the type having a flow-reversing interaction region terminated by an outlet throat from which outlet walls diverge, configured to establish a static operating pressure at the upstream end of the interaction region which is positive relative to the pressure in the outlet region.

Abstract: The converter comprises a plurality of series-connected bistable fluidic elements each having a supply input, two outputs separated by a jet splitter, and two conical inputs. The outputs of each bistable fluidic element are connected to respective control inputs of the next preceding bistable element. Feedback conduits are branched off the outputs of the last fluidic element and connected to the control inputs of the first fluidic element. The feedback conduits are closed or cleared by an electromagnetically operated valve which opens in the direction of fluid flow through the then blocked feedback conduit responsive to a signal from an electric control circuit.

Abstract: A bistable fluidic amplifier having high gain is disclosed. Power fluid is upplied through an inlet port and lobe-shaped feedback cavities downstream provide an oscillating differential pressure or flow between a pair of outlets. A pair of opposed control ports are provided between the inlet port and the feedback cavities and a differential control pressure or flow applied to the control ports creates a differential outlet pressure or flow having a gain in the range of 10-15.

Abstract: Improved fluid logic elements are disclosed employing a laminar proportio fluid amplifier connected in a feedback arrangement. Logic functions such as AND, OR, and NOR as well as the flip-flop can be implemented with a reduced power consumption and signal to noise ratio relative to turbulent wall-attachment devices. In one embodiment, the outputs of a first laminar proportional fluid amplifier are input to a second laminar proportional fluid amplifier so as to decouple the operation of the first amplifier from a utilization circuit.

Abstract: A torsional reed reference fluidic oscillator operating within 0.1% of the desired frequency over a temperature range of -65.degree. to +165.degree.F and an operating pressure of from 1 to 4 psi. The oscillator includes a torsional reed fluidic amplifier and fluidic feedback means for converting output signals from output ports of the amplifier to first and second input signals having a phase relationship for insuring operation of the apparatus as an oscillator. The amplifier is comprised of first, second and third plates, an elongated reed member, first and second torsional members and a tab, all of which are made of material having negligible thermal coefficient of expansion and negligible change in modulus of elasticity over the temperature range. The reed member is positioned within an elongated slot in the first plate, and is fixed thereto by the first and second torsional members, wherein the major axis of the torsional members is perpendicular to the plane and major axis of the reed member.

Abstract: The converter includes a pressure fluid operated, bistable fluidic element, n the form of a fluid oscillator, having a pressure fluid supply inlet opening into an interaction chamber, two outlets extending downstream from the interaction chamber to the exterior and diverging in direction at an acute angle, two control inlets communicating with the interaction chamber, and a magnetic system actuated by electric input signals and influencing the control pressure in the control inlets to deviate the pressure fluid from one outlet to the other outlet. Respective feedback conduits are branched from the outlets to respective associated control inlets. Valve arrangements are selectively actuable by the magnetic system to close or open the feedback conduits. In one embodiment of the invention, a single valve is provided in the form of an armature of the magnetic system. In another embodiment of the invention, each control inlet has a respective valve therein in the form of an armature of the electromagnetic system.

Abstract: The fluidic oscillator consists of a resonant fluid circuit having a fluid inertance and a dynamic fluid compliance. The inertance is a conduit interconnecting two locations of a chamber on each side of a working fluid jet issuing into one end of the chamber, the inertance conduit serving to transfer working fluid between the two locations. Through one or more output orifices located approximately at the opposite end of the chamber, the fluid exits from a chamber exit region which is shaped to facilitate formation of a vortex (the dynamic compliance) from the entering fluid. The flow pattern in the chamber and particularly the vortex in the chamber exit region provide flow aspiration on one side and surplus of flow on the opposite side of the chamber, which effects accelerate and respectively decelerate the fluid in the inertance conduit such as to cause reversal of the vortex after a time delay given by the inertance.

Abstract: The fluidic oscillator consists of a resonant fluid circuit having a fluid inertance and a dynamic fluid compliance. The inertance is a conduit interconnecting two locations of a chamber on each side of a working fluid jet issuing into one end of the chamber, the inertance conduit serving to transfer working fluid between the two locations. Through one or more output orifices located approximately at the opposite end of the chamber, the fluid exits from a chamber exit region which is shaped to facilitate formation of a vortex (the dynamic compliance) from the entering fluid. The flow pattern in the chamber and particularly the vortex in the chamber exit region provide flow aspiration on one side and surplus of flow on the opposite side of the chamber, which effects accelerate and respectively decelerate the fluid in the inertance conduit such as to cause reversal of the vortex after a time delay given by the inertance.