US3874416A - Liquid fluidic device - Google Patents

Liquid fluidic device Download PDF

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Publication number
US3874416A
US3874416A US447665A US44766574A US3874416A US 3874416 A US3874416 A US 3874416A US 447665 A US447665 A US 447665A US 44766574 A US44766574 A US 44766574A US 3874416 A US3874416 A US 3874416A
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United States
Prior art keywords
jet
emitter
control
nozzle
liquid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US447665A
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English (en)
Inventor
Sander B Friedman
Hugh R Martin
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University of Waterloo
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Individual
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Priority to US447665A priority Critical patent/US3874416A/en
Priority to GB826575A priority patent/GB1463932A/en
Priority to CA221,027A priority patent/CA1012889A/en
Priority to FR7506606A priority patent/FR2263405B1/fr
Priority to DE19752509373 priority patent/DE2509373A1/de
Priority to JP2645375A priority patent/JPS5627730B2/ja
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Publication of US3874416A publication Critical patent/US3874416A/en
Assigned to WATERLOO, UNIVERSITY OF reassignment WATERLOO, UNIVERSITY OF ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: CANADIAN PATENTS AND DEVELOPMENT LIMITED/SOCIETE CANADIENNE DES BREVETS ET D'EXPLOITATION LIMITEE
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15C—FLUID-CIRCUIT ELEMENTS PREDOMINANTLY USED FOR COMPUTING OR CONTROL PURPOSES
    • F15C1/00—Circuit elements having no moving parts
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/0318—Processes
    • Y10T137/0391—Affecting flow by the addition of material or energy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/2164—Plural power inputs to single device
    • Y10T137/2169—Intersecting at interaction region [e.g., comparator]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/2229—Device including passages having V over T configuration
    • Y10T137/224—With particular characteristics of control input
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/2229—Device including passages having V over T configuration
    • Y10T137/224—With particular characteristics of control input
    • Y10T137/2245—Multiple control-input passages
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/2267—Device including passages having V over gamma configuration
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/2273—Device including linearly-aligned power stream emitter and power stream collector

Definitions

  • hydraulic systems are controlled by one or more of the following hybrid systems: mechanicalhydraulic, electromechanicalhydraulic; or pneumatichydraulic.
  • the use of fluidic elements for hydraulic control provides a number of potential advantages over the other hybrid systems. Fluidic elements provide greater reliability, shorter response times, reduced cost, are more easily fabricated, and are less sensitive to environmental conditions. A fluidic element using the working fluid for control has the additional advantage of eliminating interfacing.
  • the deflection of a jet was effected either by velocity effects (momentum interchange), or by pressure effects.
  • momentum interchange fluidic device the momentum of the main jet is modified by the momentum of the control jet resulting in a deflected attitude.
  • This type of device can operate either digitally or proportionally. If a single receiver for the main jet is utilized and venting is accomplished, then any deflection greater than one full diameter will result in a loss of signal at the receiver, resulting in a digital mode of operation.
  • Another object is to provide a fluidic device having a unique mode of operation wherein the emitter jet is deflected by the control jet inward towards the control nozzle.
  • Another object is to provide a fluidic device which has relatively high amplification and/or fan-out. high pressure recovery and low power requirements.
  • the present invention essentially comprises an emitter nozzle for coupling to a liquid supply source and operative to issue a coherent and laminar liquid emitter jet, a control nozzle adapted to issue a liquid control jet having a Reynolds number less than 550 operative to deflect the emitter jet inward towards the control nozzle, and receiver means spaced downstream from the emitter for receiving the emitter jet.
  • FIG. 1 is a generalized sectional view of a liquid fluidic device illustrating the mode of deflection of the present invention under requisite conditions of flow.
  • FIG. 2 is a sectional side view of one embodiment of the invention in the form of a NOR logic element.
  • FIG. 3 illustrates graphically typical relationships between emitter jet deflection, control jet Reynolds number and emitter jet Reynolds number.
  • FIG. 4 illustrates graphically typical relationships between pressure factor or gain, control jet Reynolds number and emitter jet Reynolds number.
  • the fluid element 1 comprises an emitter nozzle 2, a control nozzle 3 and a receiver 4.
  • a liquid is supplied to the emitter nozzle 2 such that the emitter nozzle issues a laminar and coherent jet 5.
  • the emitter jet is received by the receiver 4.
  • the control nozzle 3 issues a coherent laminar jet 6 with Rey nolds number less than 550, the emitter jet 5 is deflected inward towards the control nozzle.
  • the receiver 4 is positioned such that the emitter jet 7 when deflected by control jet 6 is not received by the receiver.
  • control jet Reynolds number must be less than approximately 550 since above approximately 550 momentum effects will dominate and the device will operate in the conventional mode, with deflection away from the control jet.
  • FIG. 3 shows typical control and emitter flows required to develop given deflection angles.
  • the threshold of flow is the lower limit for effecting deflection and provides maximum deflection angles.
  • the control jet Reynolds number will be greater than 50, since below this value changes in environmental conditions tend to cause erratic operation. It was found that for reliable operation, low power requirements, and maximum amplification and fan-out, a suitable range for control jet Reynolds number is 50 to 150, particularly when operating with an emitter jet Reynolds number from 100 to 1,800. It was further found that control jet Reynolds numbers greater than I50 also resulted in satisfactory operation and it appears evident that any value less than approximately 550 may be practical in certain applications.
  • FIG. 3 illustrates that a given fluidic element may operate in the conventional mode (negative deflection angles in FIG. 3) as well as in accordance with the present invention (positive deflection). depending on the flow conditions.
  • this invention requires that the emitter nozzle operates to issue a laminar and coherent et
  • the requirement for a laminar emitter jet can be roi lLlCLi with a Reynolds number of less than 2,000.
  • FIG. 2 illustrates an embodiment of the invention suitable as a NOR logic element.
  • the liquid fluidic dexit'e comprises an emitter nozzle 21 which is supplied with a liquid through an inlet 22.
  • control nozzles 23 and 25 with inlets 24 and 26. respectively.
  • receiver 27 that commumcates with outlet 28.
  • Second receiver means or sump 29, which is integral with the body llltlllicr 20, is adapted to receive the emitter jet issuing from the emitter nozzle 2] when it is deflected by a control et issuing front either ofthe control nozzles 23 and 25.
  • the disiance from the emitter exit to the controlemitter inter action zone should be greater than l.5 emitter nozzle diameters. It was found that when this distance was less than l diameters, impingement of the control jet on the main jet caused a smooth transition in the interaction region where the main jet could tend to remain deflected en when the control flow was stopped. No ad" ⁇ antage is gained by increasing this distance more than two diameters. The only disadvantage is that the overall length of the device will be increased.
  • the preferred distance from the emitter nozzle cut to the interaction zone is two emitter nozzle diame ters llil an ⁇ additional control nozzles spaced downstream therefrom and oriented in such a manner that [lost from two control nozzles do not neutralize each other.
  • emitter nozzle It is not necessary that the emitter nozzle provide fully dewloped flovt for satisfactory operation and therefore emitter length should be as small as possible. consi tent with adequate aiming of the jet. in order to illltlll'lll/C both the power requirement and the overall we oi the device
  • the distance between the emitter and receiver is not critical other than being sufficient to permit total deflection of the emitter jet from the receiver so that the device may operate in the NOR mode. A distance of five jet diameters was found to be sufficient for the greatest angular deflection obtainable. Preferably the distance is as short as possible to minimize switching time.
  • the receiver length should be as short as possible, and should expand quickly and smoothly to minimize pressure losses.
  • the actual geometry will be a matter of choice based on the system requirements, avaiable fabrication techniques, etc.
  • FIG. 3 presents this data in a form convenient for design purposes.
  • control jet intersects the emitter jet at an angle of approximately 90. It was found that the device operated in the desired manner (deflection toward the control jet side) when the angle between the two jets varied from 45 to substantially 90. At angles less than 45, the jets tended to interact and coalesce into a single jet directed away from the control jet side, similar to a conventional.
  • the control exit should be as close as possible to the main jet in order to minimize the control flow requirements (the further away, the greater the flow required to obtain reliable interaction), and yet far enough away to permit the rapid return to the undeflected mode. It was found that a distance of 0.010 to 0.015 inches from the jet was optimum and that this distance was essen tially constant and independent of the size of the et.
  • the sump for the deflected jet should be as large as possible to prevent the receiver from submerging, which would reduce pressure recovery and cause spurious operation.
  • the nozzle passage diameters be uniform throughout the device.
  • the liquid fluidic element as shown in FIG. 2 IS designed to operate with the emitter jet issued substantially vertically downward. With a device using water and having nozzle passage diameters of 0.02 inches, satisfactory sumping and control was obtained when the alignment was within 15 from the vertical. Smaller devices operating at higher velocities are more tolerant of deviations from vertical orientation than larger devices.
  • the device is relatively insensitive to vibration (high frequency, low amplitude excursion) but susceptible to shock (low frequency, high amplitude excursion) particularly in the larger size devices where the mass of the fluid is large and the velocities low.
  • liquids have essentially no capacitance, and relatively high resistance and inductance (fluid inertia), the impedance is relatively high compared with air fluidic devices, thereby minimizing the necessity of impedance matching.
  • the primary criteria for the design of a digital fluidic device operating with a liquid are: supply power requirement, size, switching time, and pressure recovery.
  • the power needed to operate the device is essentially a function of the working fluid, and inversely proportional to size.
  • the power requirement is based on the supply pressure required to maintain the appropriate Reynolds number flow, the volumetric flow rate, and the internal losses due to the geometry of the device, including entrance losses, constriction losses, flow losses, etc.
  • the power required is a function of the emitter jet Reynolds number, cubed; and inversely proportional to the diameter of the jet.
  • the size of the device will be a function of the distance from the emitter to the control nozzle, the length of the jet from the interaction region to the receiver, the nozzle lengths, and the geometry of the inlets or outlets to or from the nozzles.
  • Switching time is a function of the velocity of the emitter jet and distance from the interaction region to the receiver. More specifically, shorter switching times are obtained with higher emitter jet velocities and shorter distances to the receiver. Decreasing the emitter jet diameter increases jet velocity and therefore decreases switching time.
  • the pressure in the receiver is proportional to the square of the ratio of the main jet Reynolds number to the jet diameter.
  • the ratio of the pressure in the receiver to that required to assure control is an equally important consideration since it is an indication of the number of elements that may be driven by the output of one element, or the fan-out of the device.
  • FIG. 4 shows the pressure factor or gain (receiver pressure/Acontrol pressure) related to emitter and control jet Reynolds number. The values given are based on emitter and control nozzle passage length of nozzle passage diameters.
  • the prime criterion with power requirements secondary the prime criterion with power requirements secondary.
  • the working fluid selected in a hydraulic oil (MlL-l-l-5606).
  • Suitable design parameters are: Nozzle passage diameter, 0.020 inches; emitter Reynolds number, L200, control Reynolds number 200; deflection angle, 10, emitter nozzle passage length, 0.20 inches, distance from control nozzle to receiver, 0.10 inches.
  • the switching speed obtainable is 0.53 milliseconds and the pressure in the receiver is 1.97 psi.
  • the power requirement is approximately 0.7 watts.
  • Logic circuits were constructed using liquid lluidit NOR elements of the type shown in Flti. 2 including .1 NOT module. an AND. OR and bistable element, and a single stage binary counter.
  • a delay or pneumatic lluidics either a capacitance or a resistance would be required, which in turn would change the llil pedance. Since the liquid fluidic device is cssentiall impedance insensitive. a resistance in the form of 1
  • the fluidic de ⁇ ice was also designed to oscillate lo feeding back the output of the receiver to the control port. It was found that the period of oscillation was a direct function of the emitter et flow. but the time on/time off" ratio was proportional to the amount of fluid fed back from the receiver to the control nozzle By metering this amount. flow into the receiver could be controlled from approximately 20 to 80 percent of the emitter flow. This effect can be applied to provide controlled variable sampling of liquid.
  • the transport time between the receiver and the con trol port is also a function of the compressibility of the working fluid in that this parameter affects the speed of propagation of the pressure wave. This allows the de vice to be used for the measurement of CUtTlPFCSSlllllll ⁇ and bulk modulus of a liquid. to determine. for exam ple. the dissolved gas contcnt.
  • the device was also used for flow measurement. De vices with nozzle passage diameters ot 0. l 25 note tlsmuld with an interconnecting conduit 48 inches long. Flow is measured by counting the frequency ot oscillation.
  • the invention also provides a device that will operate in the proportional mode since the angle of deflection is a function of control jet flow. as illustrated in FIG. 3.
  • pressure in the receiver 4 will vary from a low value when a relatively low control jet flow is supplied, that is with a large emitter jet deflection. to a greater value as the control jet flow is increased and momentum effects decrease the angle of emitter jet deflection.
  • the receiver need not necessarily be positioned coaxially downstream from the emitter as shown in FIG. 1, but may be positioned so that maximum pressure at the receiver is obtained when the emitter jet is partially deflected.
  • a liquid fluid operated control device comprising:
  • an emitter nozzle for coupling to a liquid supply source and operative to issue a coherent and laminar liquid emitter jet
  • control nozzle adapted to issue a liquid control jet having a Reynolds number less than 550 operative to deflect the emitter jet inward towards the control nozzle:
  • receiver means spaced downstream from the emitter for receiving the emitter jet.
  • control jet has a Reynolds number of from 50 to 550.
  • control jet has a Reynolds number of from 50 to I50.
  • control jet intersects the emitter jet at a distance greater than 1 k emitter nozzle diameters downstream from the emitter nozzle.
  • control jet intersects the emitter jet at an angle between 45 and substantially 10.
  • the apparatus of claim 9 wherrein the angle of intersection is substantially perpendicular.
  • the apparatus of claim 1 comprising additional receiving means for receiving the deflected emitter jet.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Nozzles (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Jet Pumps And Other Pumps (AREA)
US447665A 1974-03-04 1974-03-04 Liquid fluidic device Expired - Lifetime US3874416A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US447665A US3874416A (en) 1974-03-04 1974-03-04 Liquid fluidic device
GB826575A GB1463932A (en) 1974-03-04 1975-02-27 Liquid fluidic device
CA221,027A CA1012889A (en) 1974-03-04 1975-02-28 Laminar flow liquid fluidic device
FR7506606A FR2263405B1 (cs) 1974-03-04 1975-03-03
DE19752509373 DE2509373A1 (de) 1974-03-04 1975-03-04 Fluidbetaetigte steuervorrichtung
JP2645375A JPS5627730B2 (cs) 1974-03-04 1975-03-04

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Application Number Priority Date Filing Date Title
US447665A US3874416A (en) 1974-03-04 1974-03-04 Liquid fluidic device

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US3874416A true US3874416A (en) 1975-04-01

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US447665A Expired - Lifetime US3874416A (en) 1974-03-04 1974-03-04 Liquid fluidic device

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US (1) US3874416A (cs)
JP (1) JPS5627730B2 (cs)
CA (1) CA1012889A (cs)
DE (1) DE2509373A1 (cs)
FR (1) FR2263405B1 (cs)
GB (1) GB1463932A (cs)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3938557A (en) * 1975-03-20 1976-02-17 Canadian Patents And Development Limited Liquid fluidic device
WO1997045644A1 (en) * 1996-05-31 1997-12-04 The University Of Washington Valveless liquid microswitch

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4258754A (en) * 1979-01-15 1981-03-31 Pickett Charles G Method and apparatus for fluid sound amplification and detection of low frequency signals
JPS63168516U (cs) * 1987-04-20 1988-11-02
GB2355543A (en) * 1999-10-20 2001-04-25 Univ Sheffield Fluidic flow control and fluidic device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3234955A (en) * 1962-10-01 1966-02-15 Raymond N Auger Fluid amplifiers
US3455317A (en) * 1967-01-03 1969-07-15 Houdaille Industries Inc Method of and means for fluidic control
US3574309A (en) * 1968-06-28 1971-04-13 Foxboro Co Chambered fluidic amplifier
US3667489A (en) * 1970-01-12 1972-06-06 Fluidic Ind Inc Pure fluid device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3234955A (en) * 1962-10-01 1966-02-15 Raymond N Auger Fluid amplifiers
US3455317A (en) * 1967-01-03 1969-07-15 Houdaille Industries Inc Method of and means for fluidic control
US3574309A (en) * 1968-06-28 1971-04-13 Foxboro Co Chambered fluidic amplifier
US3667489A (en) * 1970-01-12 1972-06-06 Fluidic Ind Inc Pure fluid device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3938557A (en) * 1975-03-20 1976-02-17 Canadian Patents And Development Limited Liquid fluidic device
WO1997045644A1 (en) * 1996-05-31 1997-12-04 The University Of Washington Valveless liquid microswitch

Also Published As

Publication number Publication date
FR2263405B1 (cs) 1977-04-15
GB1463932A (en) 1977-02-09
JPS50135487A (cs) 1975-10-27
CA1012889A (en) 1977-06-28
DE2509373A1 (de) 1975-09-11
FR2263405A1 (cs) 1975-10-03
JPS5627730B2 (cs) 1981-06-26

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Owner name: WATERLOO, UNIVERSITY OF, CANADA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CANADIAN PATENTS AND DEVELOPMENT LIMITED/SOCIETE CANADIENNE DES BREVETS ET D EXPLOITATION LIMITEE;REEL/FRAME:005467/0482

Effective date: 19901002