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. stream input channel 9. in the absence of a fluid pulse Similarly, the monostable element 54 has a power from the source A, the feedback flow is insufficient to 5 stream input channel 70 terminating in an orifice 71 in cause the power stream from the orifice 3 to switch. a chamber 72 formed by the diverging output channels Upon the arrival of a fluid pulse from the source A, a 73 and 74. The element 54 further includes a control power stream resulting from the fluid pulse issues from stream input channel 75 which terminates in an orifice each of the orifices 15 and 23. In the monostable ele 76 and has its other end connected to the feedback channel ment 12, due to the absence of a feedback control stream 20 4 of the bistable element 13. The diverging output chan from the orifice 28, the power stream from the orifice 23 nels 63 and 64 of the element 53 and the diverging out flows through its normal output channel 25. In the mono put channels 73 and 74 of the element 54 are so arranged stable element 11, the feedback control stream from the that the output channels 63 and 73 gradually turn and orifice 20 causes the power stream from the orifice 15 to asymptotically merge into a first common output channel be deflected from the output channel 17 to flow through 77. Similarly, the output channels 64 and 74 merge into the output channel 8 and thence into the control signal a common output channel 78 which is connected to the input channel 35 where it emanates from the orifice 27 as control stream input channel 80 of the element 55 to a control stream. The control stream from the orifice 27 terminate in an orifice 81 in a chamber 82 of the element deflects the power stream emanating from the orifice 31 55. The element 55 further includes a power stream from the output channel 33 to flow through the output 30 input channel 83 that terminates in an orifice 84 in the channel 34. chamber 82 which is formed by the intersection of diverg The power stream from the orifice 3 will continue to ing output channels 85 and 86. The output channel 85. flow through the output channel 34 although a portion is connected to the control stream input channel 35 of the thereof is diverted thrip:gh the flow divider 42 and bistable element 3. emanates from the orifice 28 as a control stream because 35 In a similar manner the monostable element 56 has a by this time the pulse from the fluid pressure source A power stream input channel 90 terminating in an orifice is dissipated and there is insufficient flow from the orifice 9 in a chamber 92 formed by the intersection of first 38 to cause the power stream from the orifice 31 to switch and second diverging ouput channels 93 and 94. The back to the output channel 33. However, with the advent element 56 also includes a control stream channel 95 of the next pulse from the fluid pressure source A, the 40 terminating in an orifice 96 in the chamber 92 which pulse power stream emanating from the orifice 23 is now defines a control stream that is cooperative with the power deflected by the feedback control stream from the orifice stream emanating from the orifice 9. The other end of 28 to flow through the output channel 26 and thence func the control stream input channel 95 is connected to the tion as a control stream from the orifice 38 which causes fluid pressure source A. the power stream from the orifice 31 to Switch from the Similarly, the monostable element 57 has a power output channel 34 to the output channel 33 thereby com stream input channel 100 terminating in an orifice 161 pleting a full sequence of operations. Subsequent pulses in a chamber 102 formed by the diverging output channels from the fluid pressure source A will switch the output of 103 and 104. The element 57 further includes a control the element 13 sequentially in the manner explained stream input channel 105 which terminates in an orifice above. 106 and has its other end connected to the feedback When it is desired to utilize the device 10 as an oscil channel 43 of the bistable element 13. The diverging lator, the fluid pressure source A provides a continuous output channels 93 and 94 of the element 56 and the source of power fluid. In this embodiment the power diverging output channels 103 and 104 of the element 57 streams emanating continuously from the orifices 15 and are so arranged that the output channels 93 and 103 23 of the elements 11 and 12, respectively, and the feed gradually turn and asymptotically merge into a first back control streams emanating from the orifices 20 and common output channel 107. Similarly, the output chan 28 causes the power stream of the bistable element 13 to nels 94 and 104 merge into a common output channel 168 sequentially switch from the output channel 33 to the out which is connected to the control stream input channel put channel 34 and back again. Thus, an oscillator can 10 of the element 58 to terminate in an orifice 11 in be designed to have a switching rate which is a function 60 a chamber 112 of the element 58. The element 58 further of the switching characteristics of the elements 11, 12 includes a power stream input channel 113 that terminates, and 13 and the feedback fluid flow characteristics. in an orifice 4 in the chamber 12 which is formed Referring to FIG. 2, to provide greater flexibility and/or by the intersection of diverging output channels 15 and time delay variations, a triggerable flip-flop may be pro 116. The output channel 5 is connected to the control vided by the device 50 which utilizes seven fluid logic 65 stream input channel 36 of the bistable element 3. elements in which like reference characters indicate like The monostable elements 53 to 58 are arranged in order elements with respect to FIG. 1. The triggerable flip that the power stream of each favors one outlet channel flop apparatus 50 includes a bistable pure fluid logic ele normally and can be flipped or switched temporarily by ment 13 interconnected with two AND Subassemblies 51 a control stream but the power stream flips back im and 52. The AND fluid logic devices 5 and 52 are 70 mediately to its preferred condition when the control more fully disclosed in said U.S. application S.N. 306,484, stream ceases in a manner more fully described in said and each comprise three interconnected monostable NOT U.S application S.N. 306,484. In the elements 53 to 58 fluid logic elements generally of the type disclosed in the power stream favors the output channel opposite to FIG. 1 as elements 11 and 12. The AND fluid logic the one which is vented to the ambient pressure by means device 51 includes three monostable fluid logic elements 75 of openings shown as discontinuities in the respective 3,282,305 5 s chambers or by any of the other means disclosed in said 42 causes a portion of the fluid to flow through the feed U.S. application S.N. 306,484. Further to prevent un back channel 43 and is issued from the orifice 106 as a desirable pressure feedback the interconnections between control stream which deflects the power stream from the the elements may be interrupted or vented to the ambient orifice 101 to flow through the output channel 103. How pressure as indicated by discontinuities in the output chan ever, the power stream from the orifice 31 continues to nels or by any other suitable means of transmitting the flow through the output channel 34 of the bistable ele energy of the air flow solely by kinetic energy, for ex ment 13 because the power stream from the orifice 9i con ample, as shown in U.S. patent application S.N. 274,741 tinues to act as a control stream through the orifice 1 a of Peter Bauer entitled, "Improvements in Fluid Ampli which results in the absence of a control stream from the fiers.' Each of the power stream input channels of the 0. orifice 38. During this time the power streams from the elements 53 to 58 are connected to a source of continuous orifices 61 and 71 flow through the output channels 64 fluid pressure such as source B as indicated by the re and 74 respectively, thereby deflecting the power stream spective legends. from the orifice 84 to flow through the output channel 86 In operation, when it is desired to utilize the device 50 resulting in the absence of a control stream from the ori as a binary counter or triggerable flip-flop, the fluid pres 5 fice 37. Thus the bistable element 3 remains in its pres sure source A provides a source of fluid pulses while the ent condition until the arrival of the next pulse. fluid pressure source B provides a continuous flow of With the arrival of the next pulse, the combination of fluid. - the feedback flow through the feedback channel 43 and With the fluid pressure source B providing a continuous the fluid pulse emanating from the orifice 96 as a control flow of power stream fluid through the orifice 31, the fluid 20 stream causes the power streams from the orifices 105 and will flow out arbitrarily through either one of the output 9 to flow through their respective output channels 103 channels 33 or 34 during the initial operation. Once the and 93 thereby permitting the power stream from the ori power stream attaches to a wall, the Coanda effect within fice 14 of the monostable element 58 to revert to its nor the chamber 32 keeps the power stream affixed to that mal position and flow through the output channel 15 to wall in the absence of any control stream flow from the 25 provide a control stream from the orifice 38. The con orifices 37 or 38. Assuming that the fluid is flowing trol stream from the orifice 38 flips the power stream from through the output channel 33, a small fraction is diverted the orifice 31 to cause it to flow through the output chan into the feedback duct 41 by the flow divider 40 while nel 33 to provide a complete sequence of operation. Sub the remainder flows out of the extension of the output sequent fluid pulse will sequentially switch the element 13 channel 33. The flow through the feedback duct 41 30 in a manner explained above. emanates from the orifice 76 as a control stream which When it is desired to utilize the device 50 as an oscilla causes an upward deflection of the power stream from tor, the fluid pressure source A provides a continuous the orifice 71 causing the power stream to be deflected source of power fluid. In this embodiment, the power from its normal output channel 74 to the output channel streams emanating continuously from the orifices 66 and 73. However, in the absence of a pulse from the fluid 96 of the elements 53 and 56, respectively, in combination pressure source A, the power stream from the orifice 61 with the sequential feedback flow through the feedback continues to flow through its normal output channel 64 channels 41 and 43 causes the power stream of the bistable and emanantes from the orifice 81 as a control stream element 13 to sequentially switch from one of its output which deflects the power stream from the orifice 84 from channels to the other and back again. Thus, an oscillator its normal output channel 85 to flow through the output 40 can be designed to have a switching rate which is a func channel 86 resulting in the absence of a control stream tion of the switching and feedback characteristics of the from the orifice 37. Thus the power stream from the combined elements. orifice 31 continues to flow through the output channel While the invention has been described in its preferred 33. There is no control stream from the orifice 38 since embodiments, it is to be understood that the words which there is no appreciable fluid flowing through the feed have been used are words of description rather than limi back channel 43 nor is there any pulse from the fluid tation and that changes within the purview of the ap pressure source A, both of which are required to provide pended claims may be made without departing from the a control stream at the orifice 38. true scope and spirit of the invention in its broader aspects. With the arrival of a fluid pulse from the source A, a What is claimed is: control stream resulting therefrom issues from the orifice 50 1. A pure fluid logic device comprising, 66 and causes deflection of the power stream from the (a) a bistable pure fluid logic element having a power orifice 61 to cause it to flow through the output channel stream input channel for defining a power stream, 63. Since both power streams from the orifices 61 and first and second control stream input channels for 71 now flow through their respective output channels 63 defining first and second control streams respectively and 73, there is no control stream from the orifice 81 and 55 cooperative with said power stream, first and Second the power stream from the orifice 84 flips to its normal output channels each defining a path of fluid flow, monostable condition to flow through the output channel and a chamber formed by the intersection of said 85 to provide a control stream from the orifice 37. The input and output channels whereby said power stream control stream from the orifice 37 deflects the power may flow through either of said output channels in stream from the orifice 31 to cause fluid flow through the 60 the absence of a control stream, output channel 34. There is no control stream from the (b) first and second monostable pure fluid logic ele orifice 38 prior to the time the power stream from the ments each having a power stream input channel for orifice 31 flows through the output channel 34 because the defining a power stream, a control stream channel power stream from the orifice 101 acting through the ori for defining a control stream cooperative with said fice 111 continues to defect the power stream from the 65 monostable element power stream, first and second orifice 114 to flow through the output channel 516. output channels each defining a path of fluid flow, By the time the power stream from the orifice 31 and a chamber formed by the intersection of said switches to flow through the output channel 34, the fluid monostable element input and output channels pulse from the source A is dissipated and therefore the whereby said monostable element power stream nor power stream from the orifice 91 now flows through the 70 output channel 94 and provides a control stream from the mally tends to flow through said monostable element orifice 111 which deflects the power stream from the ori first output channel in the absence of a control stream fice 114 so that it continues to flow through the output while in the presence of a control stream it tends channel 116. With the power stream from the orifice 3 to flow through said monostable element second out flowing through the output channel 34, the flow divider 75 put channel, 3,232,305 7 8 (c) each of said monostable element second output defining first and second control streams respectively channels being coupled to respective ones of said cooperative with said power stream, first and second bistable element control stream input channels, output channels each defining a path of fluid flow, (d) first and second feedback channels coupled from and a chamber formed by the intersection of said said bistable element first and second output chan- 5 input and output channels whereby said power stream nels to said monostable element control stream chan- may flow through either of said output channels in nels respectively, the absence of a control stream, (e)' a first fluid pressure source connected to said bi- (b) first, second, third, fourth, fifth and sixth mono stable element power stream input channel, and stable pure fluid logic elements each having a power (f) a second fluid pressure source connected to said 10 stream input channel for defining a power stream, monostable element power stream input channel. a control stream channel for defining a control stream 2. A pure fluid logic device of the character described cooperative with said monostable element power in claim 1 in which said first and second fluid pressure stream, first and second output channels each de sources both provide continuous fluid flow. fining a path of fluid flow, and a chamber formed 3. A pure fluid logic device of the character described 15 by the intersection of said monostable element input in claim 1 in which said first fluid pressure source pro- and output channels whereby said monostable ele vides a continuous fluid flow and said second fluid pressure ment power stream normally tends to flow through source provides a pulsed fluid flow. said monostable element first output channel in the 4. A pure fluid logic device comprising, absence of a control stream while in the presence of (a) a bistable pure fluid logic element having a power 20 a control stream it tends to flow through said mono stream input channel for defining a power stream, stable element second output channels, first and second control stream input channels for (c) said first, second and third monostable elements defining first and second control streams respectively being interconnected to form a first AND fluid logic cooperative with said power stream, first and second device, output channels each defining a path of fluid flow, 25 (d) said fourth, fifth and sixth monostable elements and a chamber formed by the intersection of said being interconnected to form a second AND fluid input and output channels whereby said power logic device, stream may flow through either of said output chan- (e) a first fluid pressure source connected to said bi nels in the absence of a control stream, stable element power stream input channel, (b) a plurality of monostable pure fluid logic elements 30 (f) a second fluid pressure source connected to one each having a power stream input channel for de- input of said first and second AND devices, fining a power stream, a control stream channel for (g) first and second feedback channels connected from defining a control stream cooperative with said mono- said bistable element first and second output chan stable element power stream, first and second output nels to second inputs respectively of said first and channels each defining a path of fluid flow, and a 35 second AND devices whereby outputs are provided chamber formed by the intersection of said mono- when fluid signals appear simultaneously at said stable element input and output channels whereby first and second inputs of an AND device, and said monostable element power stream normally (h) said first and second AND devices having their tends of flow through said monostable element first outputs connected to said bistable element first and output channel in the absence of a control stream 40 second control stream channels respectively. while in the presence of a control stream it tends 8. A pure fluid logic device comprising, to flow through said monostable element second out- (a) a bistable pure fluid logic element having a power put channel, stream input channel for defining a power stream, (c) a first portion of said plurality of monostable ele- first and second control stream input channels for ments being arranged to form a first AND fluid logic 45 defining first and second control streams respectively device, cooperative with said power stream, first and second (d) a second portion of said plurality of monostable output channels each defining a path of fluid flow, elements being arranged to form a second AND and a chamber formed by the intersection of said fluid logic device, input and output channels whereby said power stream (e) first and second feedback channels coupled from 50 may flow through either of said output channels in said bistable element first and second output chan- the absence of a control stream, nels to said first and second AND devices respec- (b) six monostable pure fluid logic elements each hav tively, ing a power stream input channel for defining a (f) a first fluid pressure source connected to said bi- power Stream, a control stream channel for defin stable element power stream input channel, 55 ing a control stream cooperative with said mono (g) a second fluid pressure Source connected to said stable element power stream, first and second output first and second AND devices, and channels defining first and second paths of fluid flow (h) said first and second AND devices being connected respectively, and a chamber formed by the inter to said bistable element first and second control Section of said monostable element input and output stream input channels respectively whereby said AND 60 channels whereby said monostable element power devices provide an output signal to said bistable ele- stream normally tends to flow through said mono ment when fluid signals occur simultaneously from stable element first output channel in the absence said second fluid pressure source and said feedback of a control stream while in the presence of a con channel. trol stream it tends to flow through said monostable 5. A pure fluid logic device of the character described 65 element second output channel, in claim 4 in which said first and second fluid pressure (c) said first output channels of a first pair of said sources provide continuous fluid flow. monostable elements being connected to provide a 6. A pure fluid logic device of the character described first common output channel connected to said con in claim 4 in which said first fluid pressure source pro trol stream input channel of another monostable vides a continuous fluid flow and said second fluid pres- 70 element to form a first AND logic device, sure source provides a pulsed fluid flow. (d) said first output channels of a second pair of said 7. A pure fluid logic device comprising, monostable elements being connected to provide a (a) a bistable pure fluid logic element having a power Second common output channel connected to said stream input channel for defining a power stream, control Stream input channel of the remaining mono first and second control stream input channels for 75 stable element to form a second AND device, 9 10 (e) said second output channels of said another mono are provided from said first and second AND devices stable element and said remaining monostable ele when fluid signals appear simultaneously from said ment being connected to said bistable element first feedback channels and said second fluid pressure and second control stream input channels respec SOUICC. tively, (f) first and second feedback channels connected from References Cited by the Examiner said bistable element first and second output chan UNITED STATES PATENTS nels to respective control stream input channels of 3,107,850 10/1963 Warren et al. - 137-81.5 X one of said first and second pair of said monostable 3,117,593 1/1964 Sowers ------137-81.5 X elements, 10 3,128,040 4/1964 Norwood ------137-81.5 X (g) a first fluid pressure source connected to said bi stable element power stream input channel, and FOREIGN PATENTS (h) a second fluid pressure source connected to the 1,278,781. 11/1961 France. other control stream channel of said first and second pair of said monostable elements whereby outputs 15 M. CARY NELSON, Primary Examiner.