US3626962A

US3626962A - Fluidic logic device

Info

Publication number: US3626962A
Application number: US5653A
Authority: US
Inventors: Louis D Atkinson
Original assignee: Johnson Service Co
Current assignee: Johnson Controls International Inc
Priority date: 1970-01-26
Filing date: 1970-01-26
Publication date: 1971-12-14
Anticipated expiration: 1988-12-14
Also published as: CA927747A

Abstract

A fluidic flip-flop device of a set-reset type includes fluidic amplification. The impact position of a pair of opposed main streams occurs within a reference chamber between a pair of output chambers having output orifices in the adjacent reference walls. The walls are flat planar surfaces such that with the impact position immediately adjacent the related orifice, the impacting emitted stream flow locks to the adjacent wall as a result of fluid entrainment phenomena. This establishes a stable position. The main streams pass through the output chambers which have isolating orifices in spaced aligned relation to the output orifices. Signal nozzles to the opposite sides of the output chambers are connected to a fluidic source and adapted to reduce the strength of the related main stream by secondary injection and thereby overcome the lock-on force established by the entrainment phenomena. The impact position then switches rapidly away from the locked wall toward the opposite or second output orifice and wall. When the impact position is adjacent such second wall, the entrainment phenomena locks the stream to the second wall and establishes the second stable position.

Description

United States Patent [72] inventor Louis D. Atkinson Primary ExaminerSamuel Scott New Berlin, Wis. An0rneysAndrus, Sceales, Starke & Sawall and Arnold J. [21] Appl. No. 5,653 De Angelis [22] Filed Jan. 26, I970 45 Patented Dec. 14, 1971 [73] Assignee Johnson Service Com an ABSTRACT: A flu dic flip-flop device of a set-reset type in- Milwaukee, Wis cludes fluidic amplification. The impact position of a pair of opposed main streams occurs within a reference chamber between a pair of output chambers having output orifices in [54] FLUIDIC LOGIC DEVICE the adjacent reference walls. The walls are flat planar surfaces 15 Claims,2 Drawing Figs. such that with the impact position immediately adjacent the related orifice, the impacting emitted stream flow locks to the US. Cl. adjacent wall as a result of fluid entrainment Phenomena. This [50] Field 0' Search 137/81 5 establishes a stable position. The main streams pass through the output chambers which have isolating orifices in spaced I 56] References Cited aligned relation to the output orifices. Signal nozzles to theop- UNITED STATES PATENTS posite sides of the output chambers are connected to a flIJldIC source and adapted to reduce the strength of the related main l 5 9/1966 B-lomsen et 137/815 stream by secondary injection and thereby overcome the lock- 3'323'532 6/1967 Campagnuolo 137/815 on force established by the entrainment phenomena. The im- 3,444,878 5/1969 Mayer 137/815 pact position then switches rapidly away from the locked wall 3,446,228 5/1969 Stoufi'er et al. 137/81- toward the opposite or second output orifice and wall. When 3,469,592 9/1969 KUCZkOWSkl et al. 13'7/8 the impact position is adjacent such second wall, the entrain- 3,520,3l6 Colston ment phenomena locks the stream to the second wall and establishes the second stable position.

Load Control a/ I r I l I k 7 I f r'// I l\ I I I 2 I? A: K L 1 *E K H i k 2 a 4 a w t 1 /3 1 I ,Z9 I f I 5 I 2 1 I Control PATENTED mum: 3,626,962

Q\ INVENTOR.

Louis D. Atkinson BY WJwM, JAL SM Attorneys FLUIDIC LOGIC DEVICE BACKGROUND OF THE INVENTION This invention relates to a fluidic logic device and particularly to a flip-flop type logic device employing interacting fluid streams.

Fluidic devices employing interacting fluid streams to produce functions heretofore generally obtained only with electronic devices have been developed and applied in control and processing systems in recent years. Generally, the devices are constructed as fluid amplifying and/or switching devices. The individual devices may be interconnected for form various logic and switching functions similar to those heretofore employed in electronic control and data-processing circuits. The individual element construction and their interconnections introduces expense and complexity into the fluidic design and, thus, it is highly desirable to provide integrated fluidic devices which can perform the desired logic functions. A logic element or device which is widely employed in control and data-processing systems is a flip-flop type device and particularly of the set and reset construction wherein the logic circuit has either of two stable output positions responsive to the proper inputs.

SUMMARY OF INVENTION The present invention is particularly directed to a fluidic logic device employing only fluidic signals and particularly to a set-reset flip-flop device with bistable fluidic amplification to yield a high-pressure recovery signal in combination with a high input signal impedance.

Generally, in accordance with the present invention, the fluidic device employs the impacting stream concept as disclosed in US. Pat. No. 3,272,315, with the impacting position of the streams occurring within a reference chamber with at least one output chamber interposed between the reference chamber and source of the main stream. The main stream passes through the output chamber and in particular into an isolating orifice and output orifice. In a flip-flop construction the impacting reference chamber is located between a pair of output chambers and orifices, one to each side of the impacting position and defines an impacting flow exit means at said impacting flow position. At least one of the walls is constructed such that with the impact position immediately adjacent the related orifice, the impacting emitted stream locks to the adjacent wall as a result of fluid entrainment phenomena. This establishes a stable position. Means are provided for changing the relative strengths of the streams by a sufficient amount to overcome the lock-on force established by the entrainment phenomena. The impact position then switches rapidly away from the locked wall toward the other output orifice to create a flip-flop device. The second output orifice may be formed in a similar wall also constructed to establish a lock-on phenomena or effect. When the impact position is adjacent such second wall, the entrainment phenomena locks the stream to the alternate or second wall and establishes a second stable position. This establishes a setreset flip-flop fluidic device. Generally, the device is constructed with similar input and output apertures and chambers to the opposite side of the impact position with a slight asymmetry in the geometry or construction of the device or in the strength of the main streams such that in the absence of an input signal, the emitted impact stream is adjacent to one of the two collector or output walls and locks to such wall.

The formation of the lock-on in proximity to the collector wall and orifice, results in the flow exiting from the corresponding collector output such that a significant portion of the supply pressure level is recovered as a useful output flow signal. The set-reset flip-flop device is generally a twoor three-dimensional device symmetrically formed about the central reference or impacting chamber. This chamber is preferably referenced to atmosphere or the like to provide essentially complete isolation between the output and input signals.

Further, in accordance with a further novel aspect of the present invention, the control of the main stream strength is established by a secondary injection principle. A secondary injection control aperture and passageway is provided to each side of the output chambers and the main stream nozzles within an encircling control chamber which is generally referenced to atmosphere or the like. A control signal stream is momentarily applied directly to the main free stream in such a manner as to cause an alteration in the velocity profile of the main supply stream and thereby reduces the strength of the related stream with respect to the opposed main stream. This results in a temporary pressure imbalance resulting in the shifting of the impact position between the collector walls.

The present invention thus provides a highly improved flipflop type fluidic logic device, and particularly a set-reset fluidic flip-flop. As the output pressure level control may be achieved through the relatively small control signal levels, the device defines a bistable amplifier. The impacting stream principle produces a high input signal impedance, as well as isolation between the input and output signals.

BRIEF DESCRIPTION OF DRAWINGS The drawing furnished herewith illustrates the best mode presently contemplated by the inventor for carrying out the subject invention and clearly discloses the above advantages and features as well as others which will be readily understood by those skilled in the art from the description of the illustrated embodiment.

In the drawing:

FIG. 1 is a vertical section through a symmetrical, threedimensional, set-reset flip-flop fluidic logic unit constructed in accordance with the present invention; and

FIG. 2 is a fragmentary sectional view showing a modification to the structure of FIG. 1.

DESCRIPTION OF ILLUSTRATED EMBODIMENT Referring to the drawing, the illustrated fluidic flip-flop logic unit includes a multiple-part, integrated body structure 1 having a central core 2. A pair of similar end members 3 and 4 are similarly secured in any suitable manner in fluidtight engagement to flanges 5 formed to the opposite sides of the end faces of the central core 2.

The present invention is illustrated in a three-dimensional configuration wherein the passageways define unconfined streams within the several chambers.

The end member 3 is generally cup shaped having an outer cylindrical mounting wall 6 within which a main stream supply passageway means or nozzle 7 is located by suitable support upon the base or backwall 8. The nozzle 7 is shown integrally formed in wall 8 with the inner end axially spaced from core 2 and terminating in a main stream forming orifice or aperture 9 spaced from the end wall of the core. The main stream passageway 9 is connected to a suitable fluid supply to establish stream 10. The fluid supply may provide a gas, liquid, or a mixture thereof. Air is preferably employed because of the ready availability of air and convenience of referencing of such a system to the atmosphere.

Vents or passageways 11 are provided in the backwall S to the opposite sides of the main stream nozzle 7 and connected to a suitable reference pressure to establish a reference chamber Ila.

The opposite housing 4 is similarly constructed with a main stream passageway means or nozzle 12 in the backwall of housing 4 and terminating in a main stream aperture 9a spaced from the central body portion or core 2 to define a corresponding reference chamber l3a which is vented by passageways 13. The passageway means 12 is connected to a similar fluid supply 14 and establishes a stream 15 aligned with stream 10. The two apertures 9 and 9a thus define a pair of opposed impacting streams which impact within a reference chamber16 provided generally centrally of the main body or core 2.

The end members 3 and 4 may be similarly constructed in any suitable manner such as molding of the parts of a suitable plastic or the like or machinery of the appropriate passageways and chambers in a body member.

The central core 2 is essentially symmetrically formed with the central reference chamber 16 shown defined by a slot in the central portion to expose all sides of the impacting streams therein to atmosphere as a reference. The core 2 includes output chambers 17 and 18 formed to the opposite sides of the reference chamber 16 with apertured walls permitting the main streams to pass from the nozzles to the chamber 16. The impacting streams and are thereby referenced to the adjacent atmosphere in the illustrated embodiment and the impacting streams establish a radial flow 21 at the point of impact. The opposite axial walls 19 and 20 of the reference chamber 16 define suitable stream lock-on walls and are shown as flat, planar walls to which the impacting streamflow 21 attaches by entrainment phenomena of the impacting stream flow. The attachment wall 19 includes an output orifice 22 aligned with the respective main stream and an inputisolating orifice 33 in the opposite wall of the output chamber 17 within the central body or core 2 to separate the output chamber 17 from the adjacent reference chambers 11a and 16.

In the illustrated embodiment of the invention, the collector or output chamber 17 is formed by milling a suitable opening in the outer or exterior walls of the core 2 extending from the orifice 22 downwardly. The chamber 17 is closed by a plate 24 suitably attached to the exterior wall. An output aperture or passageway 24a is radially formed in the core 2 opposite the milled portion 17 to provide for connection of the output pressure and flow to any suitable load output device.

The core 2 to the opposite side of the reference chamber 16 is shown similarly constructed with the output chamber 18 having the output orifice 25, isolating orifice 26 and the output passageway 27. The chamber 18 and passageway 27 are shown rotated l80 from the opposite chamber 17 and passageway 24a in the illustrated embodiment of the invention.

In operation, the impacting streams 10 and 15 are connected to essentially similar supplies and produce the impacting stream flow 21 adjacent one of either of the two lock-on walls 19 or 20. A preference to either one of the walls 19 or 20 may be provided by constructing the device essentially symmetrically and having one supply stream at a very slightly greater pressure relative to the opposing supply stream or by constructing the device with slight asymmetry of the reference chamber 16 with respect to nozzles 7 and 12. In the illustrated embodiment, the preference is assumed to place stream 21 adjacent wall 19. The formation of the impacting radial stream flow 21 in close proximity to the collector wall 19 results in a lock-on to such wall with the output pressure and flow exiting through the corresponding orifice 23, collector or output chamber 17 and passageway 24a. A very significant portion of the supply pressure level is recovered as a useful output in the passageway.

The initial formation of the streams 10 and 15 creates a cone angle such thatthe emitted impacting stream flow 21 curves about with an outer peripheral portion contacting the collector wall 19. The cone-shaped flow defines a cavity 28 between the boundary of the adjacent supply streams and the wall 19. This, in effect, defines a separation bubble which is below the reference or atmospheric pressure. The result is an entrainment or aspiration fluid from the bubble 28 into the main streamflow generally in accordance with a vortex-type phenomenon. This is accompanied by a decrease of static pressure within the bubble thereby serving to hold the impacting streamflow onto the wall 19 with a resulting latching or attachment phenomena. The streamflow 21 remains in this stable condition in the absence of a selected change in the relative strength of the main supply streams.

If the relative strength of the main supply stream 10 is increased relative to the opposed stream 15 by a predetennined amount, the strength of stream 10 overcomes the lock-on force established by the interaction of the impacting streamflow 21 and the adjacent collector wall 19 to release the flow from such wall. When the pressure difference is such as to cause release of the streamflow 21, the relative stream strength is also sufficient to cause the impacting position to reverse and engage the opposite wall 20 and create a lock-on to the opposite wall 20 in a similar manner.

In the illustrated embodiment of the invention, fluid input signals are applied to the main streams 10 and 15 within the reference chambers 11a and 13a which are vented to atmosphere via vents 11 andl3. A control signal passageway, shown as a separate control signal tube 29, is mounted within the flange 5 to the left side of core 2 in FIG. 1 and extends radially inwardly terminating in a control stream aperture 30 aligned with and spaced from the main stream 15 emitted from the nozzle 12. The correct stream tube 29 is connected to a suitable source 31 of a pressurized fluid which may be of a substantially lesser pressure level than the pressure level in the main stream. The control signal source establishes a secondary or control fluid stream 32 which engages the supply stream 15 emitted from nozzle 12 and by secondary injection of deflection, varies the stream strength. The interrelationship is such that the control stream alters the velocity profile of the adjacent supply stream without necessarily changing its path and thereby reduces the effective strength of the supply stream 15 with respect to the strength of the opposed supply stream 10 at the point of impact. The secondary injection, therefore, promotes a temporary imbalance which tends to move the impacting streamflow 21 from the wall. Further, the force required to overcome the lock-on phenomena with the wall 19 will be such as to not only cause the release, but the movement of the impact position and flow 21 axially toward the opposite wall 20, Further, impacting flow is again a coneshaped flow, but not having an opposite radius of curvature directed toward wall 20 and about the output or collector orifree 25. The outer edge portion of the impacting stream 21 now curves around and makes contact with the opposite collector wall 20 such that the lock-on cavity is formed by the boundary of the second supply stream 15 and the second collector wall 20 generating a vortex-type bubble with a resulting entrainment and attachment of the impacting stream to the second wall. in the alternate position the supply stream exits through the corresponding collector or output chamber 18 and the connected passageway 27 to permit recovery of the supply pressure as a flow and/or output pressure.

The device can be shifted back to the original wall 19, as shown through the application of a suitable control signal to an opposite control nozzle or tube 33 which is similarly mounted to establish a control stream, not shown, to engage the oppositely disposed main supply stream 10.

Each of the possible alternate states is a stable condition as the impacting streamflow remains locked to the corresponding wall 19 or 20 even after removal of the input signal stream which promotes the desired switching. Further, the impact position is not disturbed by consecutive input signals on the same control nozzle or tube and only responds to complementary input signals alternately applied to the two control tubes. Thus, the illustrated embodiment of the invention defines a bistable amplifier and, in particular, a set-reset, flip-flop logic device employing the concept of the impacting streams and controlled completely by pure fluid streams and without mechanical or other components. The amplification results from the control by the relatively low-pressure signal stream 32 of the relatively high-pressure main streams l0 and 15 which in turn provide the relatively high output pressure.

Optimum results are obtained with the impacting streamflow vented into an ambient or reference chamber 16, and the main streams emitted from the main supply apertures similarly vented to a corresponding reference pressure through the chambers 11a and 13a in the corresponding end members 3 and 4. This particular referencing concept is desirable in establishing and maintaining essentially complete isolation between the output and the input signals such that the load impedance is independent of and does not in any way affect the in put flow. Dual referencing also contributes to the stability of the lock-on phenomena with a highly bistable operation, as described above.

The illustrated set-reset, flip-flop logic device may be modified to employ a single output chamber and lock-on wall if so desired. Further, by proper construction of the walls to prevent lock on and location of the walls, a proportional divided output may be obtained. Further, with the illustrated construction closing of the vents or passageways l l to the one side of the device will create a monostable-type response. Thus, with the device in the position of FIG. 1 and with the vents l 1 closed, the pressure in chamber lla will build up and force the lock-on stream from the wall 19. Application of a control signal to signal passageway 33 will deflect the main stream and cause the radial flow to switch back to wall 19. Upon removal of the control signal, the pressure again builds up in chamber 110 to again switch the stream to wall 20.

Further, the control signal passageways 29 and 33 are preferably angularly oriented or slanted as shown in the embodiment of FIG. 2. In the embodiment of FIG. 2, the unit is generally the same as i FIG. 1 and only one-half of the unit is shown in section to illustrate the modification. The second embodiment is numbered in accordance with FIG. 1 for simplicity and clarity of explanation. Generally, the central reference chamber 16 is suitably exhausted to atmosphere or other suitable reference. The output chamber 17 and passageway 24a is formed adjacent the reference chamber 16 and coupled thereto through the output orifice 23.

The control signal passageway 33 is formed in the body circumferentially offset from he output passageway 24aand is angularly oriented toward the main stream nozzle as at 34 to establish a control stream 35 having a vector opposed to that of the mean stream 10 to obtain the advantages of increased gain as set forth in the copending application of Louis D. Atkinson and Otto R. Munch entitled Multiple Purpose Fluidic Device which was filed on Mar. 3, 1969 with Ser. No. 803,588, and is assigned to the same assignee as the present invention. This permits cutoff at a significantly lower control pressure input and permits driving of a substantially greater number of output devices, not shown, from the output. Thus, if the device with a single load can recover 80 percent of the supply pressure, the percentage will decrease with the number of additional similar parallel loads. in order to maintain proper control, the plurality of parallel loads may be added until the recovery pressure is equal to the cutoff pressure or at some predetermined higher pressure to maintain a safety factor. Thus, the cutoff pressure may be 10 percent of the supply pressure. lf a safety factor of two is desired, loads may be added until the recovery pressure at each load is percent of the supply pressure. As previously noted, the slanted control stream 35 reduces the cutoff pressure and thus permits driving of a greater number of loads from the one output.

Further, the illustrated embodiments have been shown with a single control passageway for each main stream. A plurality of axially or circumferentially spaced control passageway means may of course be employed to provide alternate, accumulative or combination-type controls as the particular application requires.

The optimum construction, such as shown, incorporates the basic fluid principle of the impacting stream amplifier in combination with the lock-on phenomena produced by entrainment of the fluid adjacent the collector walls and control of the output signals by the relatively low-pressure secondary injection phenomena. The present invention has been found to provide a set-reset, flip-flop fluidic device having high-pressure recovery, high input signal impedance, as well as essentially complete isolation between the output and input signals.

1 claim:

I. A fluidic logic element comprising means establishing a pair of impacting streams establishing a lateral impacting flow between a pair of output means including output orifices to the opposite sides of the impacting flow position and including an impacting flow exit means at said impacting flow position including a lock-on wall means at a first of said orifices with the impacting streamflow locked on to such wall means by fluid entrainment with the impacting streamflow adjacent said first orifice, and control means spaced from said output means to control the relative strength of said streams to selectively overcome said entrainment force and move said impacting flow from the first orifice and thereby remove the output from said first output means and transfer said impacting flow to the second orifice and thereby to said second output means.

2. A fluidic logic element of claim 1, comprising referencing means referencing said pair of impacting streams and said lateral impacting flow to a common reference pressure.

3. The logic element of claim 1, having a pair of spaced chambers defining said output means and having spaced wall means defining a pair of spaced lock-on walls, said pair of impacting streams passing through said chambers with the impacting flow between said pair of spaced parallel wall means, and said control means includes input stream means for establishing control streams aligned one with each of said impacting streams.

4. The logic element of claim 1, having a pair of spaced chambers defining said output means and having spaced parallel wall means defining a pair of lock-on walls, said pair of impacting streams passing through said chambers with the impacting flow intermediate said pair of spaced parallel wall means and having means to initially attach the impacted streams to one of said wall means, an output means including one of said wall means, and a pair of input stream means for establishing a pair of control streams aligned one with each of said impacting streams. 1

5. The fluidic logic element of claim 1, including a second lock-on wall means forming a part of said impacting flow exit means at the second of said output orifices with the impacting streamflow locked on to such wall by fluid entrainment with the impacting streamflow adjacent said second orifice, and said control means controlling the relative strength of said streams to selectively overcome said entrainment forces and move said impacting stream between the first and second orifices.

6. The fluidic logic element of claim 5, having first and second control stream forming means aligned one each with each of said impacting streams and selectively establishing a secondary injection control stream for correspondingly reducing the corresponding effective strength of the related impacting streams.

7. The logic element of claim 1, having a pair of spaced output chambers defining said output means and each having spaced aligned orifices for the corresponding impacting stream, the opposed walls of said chambers being parailel and defining a pair of lock-on walls, reference chamber means secured to the opposite ends of the chambers and having supply nozzles spaced from the corresponding spaced chamber means, and said nozzles being asymmetrically mounted with respect to said lock-on walls and thereby establish an initial attachment of the impacting streamflow to one of said wall means, and a pair of input stream means for establishing a pair of secondary injection control streams aligned one with each of said impacting streams within said corresponding reference chamber.

8. The logic element of claim 7 wherein the output chambers are formed in central core, said reference chamber means including outer walls secured to the opposite ends of the central core and said supply nozzles being centrally secured within said outer walls, and said input stream means including a secondary injection stream tube for each impacting stream mounted between the corresponding output chamber and the nozzle and in slightly spaced relation to the main stream.

9. A fluidic logic element comprising stream source means establishing a pair of impacting streams establishing a lateral impacting flow position, and impacting flow exit means aligned with the impacting flow position, and output chamber means interposed between the impacting flow exit means and said source means in the path of a first of said streams and having an input-isolating orifice spaced from said source means and aligned with said first stream and an axially spaced output orifice aligned with said first stream immediately adjacent the exit means for the impacting flow position, and means coupled to at least one of said streams to control the relative strength of said impacting streams.

10. A fluidic logic element of claim 9, comprising referencing chamber means referencing said impacting flow position and said stream source means to a common reference pressure.

11. The 'fluidic logic element of claim 9, including a corresponding second output chamber means correspondingly located in the path of said second stream.

12. The fiuidic logic element of claim 9, having an apertured reference chamber connecting the output chamber means to said first stream source means to reference said first impacting stream, and means to close said reference chamber.

13. The fluidic logic element of claim 9, wherein said control means includes a control stream forming means angularly oriented in opposed relationship to the flow of a first of said streams and selectively establishing a control stream to reduce the strength thereof and overcome said entrainment force and thereby move said impacting flow from the first orifice.

14. A fluidic logic element of claim 13, including a plurality of parallel fluidic load connecting means connected to said output chamber means.

15. The fluidic logic element of claim 14 wherein, said exit means includes a lock-on wall at said output orifice with the impacting stream flow locked on to such wall by fluid entrainment with the impacting streamflow adjacent said output orifice.

I i t i i UNITED STATES PATENT OFFICE CERTIFICATE OF- CORRECTION Patent No- 3 626 .962 D ecemb er l l9ll Inv (X) LOUIS D. ATKINSON It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, Line 12, cancel "for" and insert Column 2, Line 42, cancel "fluidtight" and insert fluid tight Column 3, Line 22, cancel "33" and insert Column 3, Line 68, cancel "phenomenon" and insert phenomena Column 4, Line 36, cancel "not" and insert now Column I 5, Line 3, cancel "in put" and insert input Column 5, Line 23, cancel the "i" before Fig. l

and insert in Column 5, Line 33, cancel "he" and insert the Column 6, Line 65, before "central" insert CLAIM 8 a Signed and sealed this L th day of July 1972.

(SEAL) Attest:

EDWARD I I.FLETCHER,JR. ROBERT GOT'I'SCHALK Attesting Officer Commissioner of Patents FORM (1069) USCOMM-DC 60376-P69 UVS GOVERNMENT PRINTING OFFICE 2 I969 0-365-3/

Claims

1. A fluidic logic element comprising means establishing a pair of impacting streams establishing a lateral impacting flow between a pair of output means including output orifices to the opposite sides of the impacting flow position and including an impacting flow exit means at said impacting flow position including a lock-on wall means at a first of said orifices with the impacting streamflow locked on to such wall means by fluid entrainment with the impacting streamflow adjacent said first orifice, and control means spaced from said output means to control the relative strength of said streams to selectively overcome said entrainment force and move said impacting flow from the first orifice and thereby remove the output from said first output means and transfer said impacting flow to the second orifice and thereby to said second output means.

4. The logic element of claim 1, having a pair of spaced chambers defining Said output means and having spaced parallel wall means defining a pair of lock-on walls, said pair of impacting streams passing through said chambers with the impacting flow intermediate said pair of spaced parallel wall means and having means to initially attach the impacted streams to one of said wall means, an output means including one of said wall means, and a pair of input stream means for establishing a pair of control streams aligned one with each of said impacting streams.

7. The logic element of claim 1, having a pair of spaced output chambers defining said output means and each having spaced aligned orifices for the corresponding impacting stream, the opposed walls of said chambers being parallel and defining a pair of lock-on walls, reference chamber means secured to the opposite ends of the chambers and having supply nozzles spaced from the corresponding spaced chamber means, and said nozzles being asymmetrically mounted with respect to said lock-on walls and thereby establish an initial attachment of the impacting streamflow to one of said wall means, and a pair of input stream means for establishing a pair of secondary injection control streams aligned one with each of said impacting streams within said corresponding reference chamber.

8. The logic element of claim 7 wherein the output chambers are formed in a central core, said reference chamber means including outer walls secured to the opposite ends of the central core and said supply nozzles being centrally secured within said outer walls, and said input stream means including a secondary injection stream tube for each impacting stream mounted between the corresponding output chamber and the nozzle and in slightly spaced relation to the main stream.

9. A fluidic logic element comprising stream source means establishing a pair of impacting streams establishing a lateral impacting flow position, an impacting flow exit means aligned with the impacting flow position, and output chamber means interposed between the impacting flow exit means and said source means in the path of a first of said streams and having an input-isolating orifice spaced from said source means and aligned with said first stream and an axially spaced output orifice aligned with said first stream immediately adjacent the exit means for the impacting flow position, and means coupled to at least one of said streams to control the relative strength of said impacting streams.

11. The fluidic logic element of claim 9, including a corresponding second output chamber means correspondingly located in the path of said second stream.

12. The fluidic logic element of claim 9, having an apertured reference chamber connecting the output chamber means to said first stream source means to reference said first impacting stream, and means to close said reference chamber.