Feb. 1, 1966 E. GROEBER 3,232,305 FLUID LOGIC APPARATUS Filed Nov. 14, 1963 2 Sheets-Sheet l UTZATION APPARATUS 4f 43 FLUID PRESSURE SOURCE B FLUID PRESSURE SOURCE A F. G.1. INVENTOR. AUGEW GROESEA "1/4, A77OAPWAY Feb. 1, 1966 E. GROEBER 3,232,305 FLUID LOGIC APPARATUS 2 Sheets-Sheet 2 INVENTOR. AUGAW GAOEs EAP A77OAPAWAY 3,232,305 United States Patent Office Patented Feb. 1, 1966 2 channel 9 which terminates in the orifice 20 to provide 3,232,305 a feedback control stream emanating from the orifice FLUID. LOGIC APPARATUS 20 that is cooperative with the power stream emanating Eugen Groeber, Salt Lake City, Utah, assig or to Sperry from the orifice 5 for deflecting the power stream to Rand Corporation, Great Neck, N.Y., a corporation of 5 flow through the output channel 18 in lieu of the output. Delaware channel 17. The power stream emanating from the ori Filed Nov. 14, 1963, Ser. No. 323,724 fice 15 normally tends to flow through the output channel 8 Claims. (C. 137-81.5) 27 because of the well known Coanda effect which pro vides a stable dynamically formed and sustained pres The present invention relates to fluid logic devices of sure gradient across the power stream within the chamber the type utilizing a triggerable bistable element suitable 0 16 which keeps the power stream affixed to the wall as for use in fluid digital computer systems. sociated with the output channel 7 and because of the The problem of making a digital counter, partial Sun vent 21 in the wall associated with the output channel or partial difference of digital functions is simplified if a 18 in a manner more fully disclosed in U.S. patent ap triggerable flip-flop is available. The present invention plication S.N. 306,484, entitled, "Fluid Logic Device,' of provides a pure fluid triggerable flip-flop suitable for this Groeber and Thorne, Sr., filed September 4, 1963. purpose. The fluid logic apparatus of the present inven Similarly, the monostable element 12 includes a power tion may also be utilized as an oscillator. stream input channel 22 terminating at an orifice 23 in the Prior digital computers utilized logic elements that were downstream wall of a chamber 24 formed by the intersec either electrically or mechanically operated. The elec 20 tion of first and second diverging output channels 25 and tronic elements suffered from the disadvantages of being 26. The element 12 also includes a feedback control relatively delicate, sensitive to environmental conditions stream input channel 27 which terminates in the orifice 28 and relatively expensive while the equivalent mechanical to provide a feedback control stream emanating from the elements included moving parts having high inertia char orifice 28 that is cooperative with the power stream emant acteristics and consequent slow reaction time and they 25 ing from the orifice 23 for deflecting power stream to flow tended to be susceptible to malfunctions. through the output channel 26 in lieu of the output chan It is therefore a primary object of the present invention nel 25. The power stream emanating from the orifice 23 to provide fluid logic apparatus for controlling fluid flow normally tends to flow through the output channel 25, as without utilizing moving parts. explained with respect to the element 11 because of the It is a further object of the present invention to provide 30 Coanda effect and the vent 29. , fluid logic apparatus which produces a logic function that A pulsed or continuous fluid pressure source A is con is relatively insensitive to environmental conditions and nected to the power stream input channels 4 and 22 to is extremely reliable. provide pulsed or continuous power streams from the ori It is another object of the present invention to provide fices 5 and 23, respectively, in a manner to be more full a simple pure fluid logic apparatus of the triggerable flip 35 ly explained. flop type. The bistable fluid logic element 13 includes a power The above objects are achieved by pure fluid apparatus stream input channel 30 terminating at an orifice 31 in utilizing a bistable fluid logic element in conjunction with the downstream wall of a chamber 32 formed by the in at least two monostable fluid logic elements. The bistable tersection of first and second diverging output channels element is sequentially switched as a function of its con 40 33 and 34. The other end of the power stream input: dition as related to the inputs provided to the monostable channel 30 is connected to a continuous power stream elements. Switching times as well as the particular ap fluid pressure source B which provides a continuous fluid plication for which the combination is to be utilized may. flow that emanates as a power stream from the orifice 31. be made a function of the characteristics of the number The element 13 further includes first and second control and type of the monostable elements. stream input channels 35 and 36 which terminate in ori These and other objects of the present invention will 45 fices 37 and 38, respectively, in opposite walls of the become apparent by referring to the drawings in which: chamber 32. The orifices. 37 and 38 define respective FIG. 1 is a schematic diagram of a three element pure paths of control stream fluid flow that are opposed with fluid logic triggerable flip-flop device; and respect to each other and cooperative with the power FIG. 2 is a schematic diagram of a seven element pure stream from the orifice 31. The output channels 33 and fluid logic triggerable flip-flop device. 34 are arranged symmetrically with respect to the power Referring to FIG. 1, the pure fluid logic device 10 in stream from the orifice 3; in order that in the absence of cludes a pair of monostable NOT elements 1 and 12 in any control stream from either of the orifices 37 or 38, terconnected with respect to a bistable element 13. The the power stream arbitrarily flows through one of the out elements 11, 12 and 13, may, for example, be made from put channels 33 or 34 and is not arranged to flow through a plurality of flat plates as disclosed in U.S. Patent Num 55 any particular one of them. bers 3,001,698 and 3,030,979 although other constructions The element 13 includes a flow divider 40 in its output in the art are suitable for practicing the present invention. channel 33 in order that a portion of the fluid flowing in said patents, the desired channel configuration is cut, through the output channel 33 is diverted through the etched, stamped, or otherwise formed in one of the plates. divider 40 which is connected by a feedback channel 4. Since this construction is well known in the art, the draw 60 to the control stream input channel 19 of the element 11. ing shows only the channel configurations which define Similarly, a portion of the flow through the output chan the paths of fluid flow for the present invention. It will nel 34 is diverted through a flow divider 42 which is con be appreciated that the term "channel” as used herein nected by a feedback channel 43 to the control stream in refers to conduits, pipes, tubes, closed ducts, or other put channel 27 of the element 12. The output channels closed passageways for conveying fluid, and the term "ori 65 33 and 34 of element 13 have extensions downstream fice' includes restricted or unrestricted openings. from the respective flow dividers 40 and 42 that are con The monostable element 1 has a power stream input nected to utilization apparatus as indicated by the legend. channel 14 terminating at an orifice i5 in the downstream in operation, with the apparatus 10 utilized as a trgiger wall of a chamber 16 formed by the intersection of first able flip-flop or binary counter, the fluid pressure source and second diverging output channels 17 and 18. The 70 A provides a source of fluid pulses while the fluid pres element 11 also includes a feedback control stream input sure source B provides a continuous flow of power stream 3,282,305 3 4. fluid through the orifice 3i, the fluid from the orifice 3 53, 54 and 55, and similarly the AND fluid logic device will flow out arbitrarily through either one of the output 52 includes three monostable fluid logic elements 56, 57 channels 33 or 34 during the initial operation. Once the and 58. power stream attaches to a wall, the Coanda effect main The monostable element 53 has a power stream input tains the power stream affixed to that wall in the absence channel 60 terminating in an orifice 61 in a chamber 62 of any control stream flow in the element 13. Assuming formed by the intersection of first and second diverging that the power stream is flowing through the output chan output channels 63 and 64. The element 53 also in nel 33, a small fraction of the fluid is diverted through cludes a control stream channel 65 terminating in an the feedback duct 4 by the flow divider 40 while the re orifice 66 in the chamber 62 which defines a control mainder flows out the extension of the output channel 33. 10 stream that is cooperative with the power stream emanat The flow through the feedback channel 4i is directed ing from the orifice 61. The other end of the control through the orifice 20 of the element 11 into the interac stream channel 65 is connected to the fluid pressure Source tion region of the chamber 6 by means of the control A as indicated by the legend.