US2524213A - Gaseous discharge tube system - Google Patents

Description

Oct. 3, 1950 N. B. WALES, JR 2,524,213

GASEOUS DISCHARGE TUBE SYSTEM Original Filed June 18, 1947 Sheets-Sheet It 2. g)

IN V EN TOR.

\ NATHANIEL B.WALES JR.

ATTORNEY.

Oct. 3, 1950 N. B. WALES, JR

GASEOUS DISCHARGE TUBE SYSTEM 2 Sheets-Sheet 2 3O OUTPUT A 7 3 p T a n6 W" T V N it. A

'g l\ I g FLL g m V T. t I illllllllllmllllllllll|lll|-+ r INVENTOR. f g NATHANIEL B. w LEs JR. T ATTORNEY. V

Patented Oct. 3, 1950 GASEOUS DISCHARGE TUBE SYSTEM Nathaniel" Bl lwales, Jr., Morristown, N. J., as-

signoritomRemington Rand, Inc., NewjYork, N. Y.', acorporation of Delaware Original application June 18, 1947, Serial Nqi 1, 1948'; serial 12,234

i Claims. (o1.s15+201) -1 This inventionrrelatesto a supply circuit for a multi-discharge tube and more particularly relates to the energizing circuit for a counter and storage tube which is fully described in my copending application,"Serial No.::755,529,

filed June 18, 1947, nowvPatentiNom2,443,407,

issued June 15, 1948, for a Gaseous Discharge Device, of which the: present applicationds a division.

In the preferred "formof'my invention I pro vide a circuit for supplying a discharge tube having a system orthree: anodes, each having a plurality of spaceddischarge points; so positioned as to form a path of sequentiallyi alternate anodes with qres ectfto acommon cathode located. parallel to thispath, air of these-elem trodes being supported "within a suitabla'preferably low pressure gaseous" disoharge atmosphcre. Thus, in thisformfofmy invention, when a potential inexcess of the breakdown" voltage is applied to any one of theseanodesraative to the common cathode and'through a cathode series load resistor, a visible "discharge wiutake place at only one oithe-plurality or:discharge points for that anode because oftheiiact that as soon as oned'i'scharge is establishedvat adischarge point, its discharge currentfl passing through the series load resistor causes" a'wdrop in the anodeto cathode potential such that this lowered potential isinadequate to initiate a second discharge atany other point on this anode. It is this mutually exclusive dischargereature which is the-basisofthe integratingcharacter istics of the system.

My invention provides for the transfer" of discharge from one discharge point 3 of the master electrode to its neXtdischarge point by' causing an input pulse which is to-be countedor integratedyfirst to de energize the master electrode,

andthen to energizesequentially the othertwo intervening discharge electrodes beforere-ene1'- gizing the master electrode; thereby physically transferring the discharge through adefinite directed displacement representing one step on the multiple "master electrode. The reason why the discharge will transfer only to the adjacent discharge pointinstead' of to soine arbitrarily remote point of the same "adjacent multiple electrode, is that the presence of io'ns 'in the region surrounding the discharge and persisting? even after the exciting voltage for the discharge has been removed, sets up preferential conditions for the re-establishment'of a discharge in the neighborhood of the region in which a discharge has just terminated. T 1 155 iI-OI IY" twq mu ple Divided and this applicatifin March alternate electrodes were usedatherenwould: be an ambiguity as to whichfof theadjacent- :points would capture the terminating dischargeg whereas with three sequentially alternategwelectrode systems there will. be; a positive directedirpreference for the discharge to move alongtthezelectrode path determined bylthe order of excitation of the electrodes adjacent to;thepimastelnielectrode. i i

It is to be noted that my inventiongwillzzoperate equally well ..using a common;;a.node and three multiple cathodes, orindeed; :the same1e1ectrode geometry will o erate when-:iexcitation is supplied by alternating potentials. Further, the path of the alternate: discharge 'pointsraxnay be closed so as to comprise acyclic-or self-resetting counter, or the path mayibeirlinearor non cyclic with special means providedfor; resetting. Also,

within the principle of mysinvention ranysnumber of sequentially alternateirzniultiple electrodes above three may be used forsspecial applications where it is desired toseparatezthetpossibleapoints of discharge by a greaterrdistancesthan possible with three sets of discharge points. l

The sequential transfer *of the; arc discharge betweenlthe three multiple electrodestanda the common electrode iis accomplished byxjmy preferred circuit shown in the accompanying drawings. in this circuit the transfer: iswreiiected by supplying the 1 intermediate electr-odesnwith capacitance stored potentials of progressively lower values than thatiof thearnaster electrode so that on the momentary removalpbyaana incomin pulseto be countedof the master electrode potential the discharge. is captured;and

maintained for a short time bytheradjaicent master electrode point which is one removed and in the desired direction of displacement from the initial master electrode discharge On re-excitation of themaster electrode-the-discharge is thus established at-this displaced position. In this casethe' preferentialdirectmn of discharge transfer is determined-by the diwith a special electrode for resetting the counter to a zero or index position. Means are shown for causing this device to yield an output impulse each time the discharge passes this index position. Thus a group of such counting tubes connected in cascade so that the successive tubes in the series are caused to count in response to the index output impulses of the preceding stage will comprise a system capable of counting in any number system as determined by the number of discharge points provided'on each of the master electrodes. In the decimal system each such tube thus comprises a decade counter.

It is to be noted in the art of electronic counting that an electronic decade of either the Eccles- Jordan or thyratron rin type employs a minimum of four to ten tubes together with appreciable associated circuitry, in contradistinction to the single unit simplicity of the present invention in which the register is visibly indicated on a calibrated dial.

In addition, this invention has utility as a frequency divider, such as those used in television synchronization circuits, and as a predetermined limiting counter, such as those used'in packaging machinery.

One object of this invention is to provide a simple and visible means for registering the count of rapid or random impulses in any number system.

A second object is to make possible a self resetting visible counter of compact and economical construction.

A third object is to provide an electrical device capable of yielding one output pulse in response to the accumulation of each predetermined number of input impulses.

Other objects are implicit in the accompanying specification and claims.

In the drawings:

Fig. 1 is a cross-section taken through the axis of th counting tube.

Fig. 2 is a sectional view of Fig. 1 taken along line 22 of that figure.

Fig. 3 is a schematic diagram of connections of the circuit used with the counting tube.

Referring now to the drawings, the electrode structure of the counting tube is mounted within an envelope II] which is evacuated, degassed, and

then filled with a suitable discharge gas at reduced pressure. The central electrode support wire H passes through and is supported by the press of the envelope [2. The electrode spider l3 (hereinafter called the master electrode) cornprises a group of nine radial fingers Id at 36 intervals stamped from a single sheet of metal and doubly bent so that the pointed ends of the discharge fingers l4 lie in a plane displaced below but lying parallel to the central circular hub I3 of the electrode. Spider I3 is centrally secured to and supported by lead wire H. It is to be noted that the tenth discharge finger of electrode I3 is missing, and that the place which it would occupy is taken by the resetting or index electrode 16.

The mid-electrode spider ll comprises a fiat stamped metal piece having ten radial equispaced pointed discharge fingers l8 which lie in the same plane as the ends of discharge fingers Hi of the upper electrode l3, but spaced therefrom by 12 displacement. Spider IT is centrally secured to metal sleeve 2!] which is supported on and insulated from central wire II by the glass sleeve 2|. Lead wire 22 is secured to and affords external connection to sleeve 26 and its @1 trode I1.

The lower electrode spider 23 is similar to spider l3 but has its ten radial equispaced discharge fingers 24 bent upward and outward so that the discharge points lie in the same common plane as electrode points [4 and 18. The points of the electrodes [4, l8, and 24 thus lie on a common circle and, together with the radially bent electrode discharge point !6 which is supported by wire 25 and the press of envelope l0, form a series of 30 equispaced sequentially alternate discharge electrodes. Electrode 23 is centrally secured to metal sleeve 26 which in turn is insulated from and supported by glass sleeve 21 concentric with and supported on sleeve 20. Lead wire 28 passing through the press of envelope I0 is secured to sleeve 25 and forms external connection to electrode 23.

The common electrode comprises a cylinder of metal 30 supported on lead wire 3! and maintained concentric with the circle of discharge points by the mica insulating spacer disk 32.

The external connections to the tube are thus: master electrode ll, first transfer electrode 22, second transfer electrode 28, index electrode 25, and common electrode 3 I.

The circuit of Fig. 3 comprises a voltage supply shown as a battery 33 leading to a network of resistors R1 to R8 which may be considered to be a series of four parallel voltage dividers or bleeders. The master electrode lead II is connected to the junction of resistors R1 and R2. The values of R1 and R2 are chosen such that the potential of the junction is well above the breakdown voltage of the master electrode 13, say 150 volts, and such that enough current may flow through R2 to sustain the discharge without dropping the potential of the junction to the extinction potential. In contradistinction to this discharge sustaining value of R2, the values of the resistors R4, R6, and Rs are such as to be unable to sustain a discharge from energy supplied by battery 33. The first transfer electrode lead 22 is connected to the junction between R3 and R4 and the values of these are chosen so as to maintain the potential of IT, relative to the ground lead 34, at a point lower than that of the master electrode. For 150 volts on the master electrode this potential might be 140 volts. The second transfer electrode lead 28 is in turn connected to the junction of resistors R5 and Re and the values are chosen so that this potential is maintained lower again than first transfer electrode II. On the same scale this value might be volts.

The index electrode lead 25 is maintained at a potential substantially identical with that of second transfer electrode 28 by its own voltage divider R7, R8. Consequently, since it geometrically occupies a position in the tube corresponding to the location of the discharge points 24 of electrode 23 it will perform identically, from a functional standpoint, with the behaviour of electrode 28.

All discharge currents passing through the tube also pass through the common electrode load resistor R9. It is the voltage drop across this resistor which causes the discharge within the tube to be mutually exclusive of the several alternative discharge points.

The capacitors C1, C2, and C3 are so connected as to supply transient current to the transfer electrode leads 22, 28, and 25 respectively. The time constant of the values R3 01, is chosen so as to be small with respect to the length of input pulse which is to be counted. The time .con-

rant R 02 and R7 o: are chosen to be equalito or greater than the pulse duration'inorder to provide overlap. a

The operation of my inventionis as follows: Let it be assumed that it is desired to count electrical input impulses in the form of square waves applied to terminals 34, 35. These input impulses after passing through the coupling condenser C41 will produce voltage. impuljsefsappearing across resistor R1. For thecorrect magnitude and. polarity of these impulses theseftransient potentials will oppose the potential ap pearing across Rl'by virtue of the loattery 33, and consequently the potential of the master electrode is will drop with respect to the common electrode 30 until it is inadequate to sustain the discharge which has been maintained from enact the fingers M of masterelectrode l3. As before noted, since the values of, RA, Re, and R8 are sufiiciently high that no discharge may be maintainedthrough them by energy flowing from the battery, the steady state of the system necessarily requires that a continuous discharge be taking place at one of the master discharge points l4. As this discharge approaches extinc tion due to the opposing pulse voltage across R1 the diminishing discharge current through common electrode 30 resistor Racauses the potentials of all the remaining, electrodes to rise with respect tothe common electrode. However, since the first transfer electrode lead 22 is at the highest potential relative to the common electrode as determined by the voltage divider R3 R4, and since one of its discharge fingers I8 is adjacent to the ionized region through which the discharge had been maintained, that finger of the first transfer electrode will capture the discharge in preference to the finger 24 of the second transfer electrode which is on the other side of the master electrode fingerfwhich had maintained the discharge, because 'of the ,higher potential of .58. As soon as lectrode l8 captures the discharge the current through R9 again drops the anodes-to-cathode potentials so e,

that no other;discharge is possible. However, the current of this captured discharge. is being supplied by condenser 01 and consequently in a short timethis charge will be exhausted allowing the current through R9 ta drop again and the relative anodes-towathode potentials to rise. At this point since the potentials on Hand 18 are respectively disabled and exhausted the only remaining appreciable potential gradient and idiacent,to the, last ,point of discharge is that betweenthesecondtransfer electrode finger 24 and the common electrode 30. e

For this reason, the discharge will now pass tothe adjacent finger 24 of the second transfer electrode, and the dischargewill remain there until, the decaying potential, across condenser C2 becomes inadequate to sustain the discharge. By this time, how ever, the blocking pulse on resistor R1 will have disappeared thereby allowing the discharge to pass to the master electrode 54 again. Thus, in response to the pulse the discharge has progressively transferred itself from one finger of the master electrode to its next one thereby visibly registering the addition of the impulse. This process is repeated for successive impulses until the index position is reached. When the input impulse which will make the transit of electrode l6 occur, the discharge moves as above described from the number 9 finger of the master electrode to the adjacent finger of the first transfer electrode.

saga

Thence thedischarge moves on to discharge point ,lB. because]the electrical conditions on it are Lidntical to those of the second transfer electrode. From point 16 the discharge "r'novesas before backonto the zero finger of the master electrode [4, but in the process of discharging condenser C3 of the index electrode a transient changeof the potential of lead 25 has been generated" "Since this transient occurs only dnce [per revolution ofthe electrode cycle, it maybe utilized as an output pulse appearing at output terminals36, 34. Thiso'utputpulse may be c oupled to' the input connections ofano'ther such system as shcwn in Fig. 3 thereby comprising two decade counter, and the process may obviously be extended, to any number of cascade counter decades. Alternatively, since the output pulse irequency has an exact fractional. relation to the input frequency, it may be utilized as a frequency divider It is evident that any desired number of discharge points may be incorporated in the discharge cycle, either for the purpose of counting in other number systems than the decimal system, or for specificapplications where particular frequency divisions or predetermined counting limits'are desired.

It may be'noted that there is an optimum duration and form of the input pulses which are to:

be counted,'but in practice it is found that there are wide limits as to these specificationsdue to' the long persistence of ions in the neighborhood of thelast transfer electrodedischarge. For this:

reason a minimum of'input pulse shaping cir-' cuitry is necessary.

In the circuit of Fig.3 means are provided for resetting the'system to the'zero position. These comprise the two switches M and 38. To reset the decadethe normallyclos'ed'switch 31- is opened thus causing all discharge in the tube to die out in a very short time by opening the lead to battery 33. Normally open switch" 38 is thus closed thereby impressing the full battery voltageon the indexelectrode Hi. This initiates a discharge at this point which will then transfer to the zero finger'of the master electrodeon the reclosing of switch 3'! and the subsequent opening of switch 38.

It n be evident that there are a great number of geometrical forms and circ'uitmeans for incorpcratingthe principle of my invention, and

for this reason it is riot"to *be construed as: a fjlijmitation of the scope of my concept that only cnegeometry and one circuit are shown in the drawings.

Wh'atis claimedis: I r r e r 1. Agaseousjdischarge tubelsystem comprising;

a fillederivelopef a cathode; a plurality of a c'desl each having a numbero'f discharge fingers equally spaced from the cathode in sequentially alternate arrangement; a direct current l supplygcircuit forjeachfof said anodes supplying electrical power'causing a glow discharge between one'of'the fingers and the cathode, each of said supply circuits including a voltage divider connected across a common source of direct current, a connection between the mid-point of each voltage divider and one of the anodes, and a common resistor connected between the cathode and the negative terminal of the source of direct current; and a transient control circuit causing the glow discharge to move from one anode finger to another, said circuit including input terminals where a negative pulse may be applied between the negative terminal of the source of direct current and one of the anodes.

- 2. A gaseous discharge tube system comprising; a gas filled envelope; a cathode; a master anode and two transfer anodes each having a number of discharge fingers equally spaced from the cathode in'sequentially alternate arrangement; a direct current supply circuit for the master anode and the transfer anodes supplying electrical power causing a glow discharge between one of the fingers and the cathode, each of said supply circuits including a voltage divider connected across a common source of direct current, a connection between the mid-point of each voltage divider and one of the anodes, and a common resistor connected between the cathode and the negative terminal of the source of direct current; and a transient control circuit causing the glow discharge to move from one anode finger to another when a negative pulse is applied thereto, said circuit including input terminals for receiving a negative pulse and applying it across the negative terminal of the source of direct current and the master anode.

3. A gaseous discharge tube system comprising; a gas filled envelope; a cathode; a master anode and two transfer anodes each having a number of discharge fingers equally spaced from the cathode in sequentially alternate arrangement; a direct current supply circuit for the master anode and the transfer anodes supplying electrical power causing a glow discharge between one of the fingers and the cathode, each of said supply circuits including a voltage divider connected across a common source of direct current, a connection between the mid-point of each voltage divider and one of the anodes, and a common resistor connected between the cathode and the negative terminal of the source of direct current; a transient control circuit causing the glow discharge to move from one anode finger to another when a negative pulse is applied thereto, said circuit including input terminals for receiving a negative pulse and applying it across the negative terminal of the source of direct current and the master anode; and a capacitor connected between each transfer anode and ground.

4. A gaseous discharge tube system comprising; a gas filled envelope; a cathode; a master anode having a plurality of discharge fingers for sus taining a gaseous discharge between one of the fingers and the cathode in the absence of an input pulse, and two transfer anodes each having a plurality of discharge fingers, the discharge fingers of the three anodes arranged in alternate sequential arrangement; a direct current supply circuit for the master anode supplying electrical power and causing a glow discharge between one of the master anode fingers and the cathode; a direct current supply circuit for each of the transfer anodes supplying electrical power and causing a transient glow discharge between one of the transfer anode fingers and the cathode when a negativepulse has been applied to the system, each of said supply circuits including a voltage divider connected across a common source of direct current, a connection between'the midpoint of each voltage divider and one of the anodes, and a common resistor connected between the cathode and the negative terminal of the source of direct current; a transient control circuit causing the glow discharge to move from one anode finger to another when a negative pulse is applied thereto, said circuit including input terminals for receiving a negative pulse and applying it across the negative terminal of the source of direct current and the master anode; and a capacitor connected between each transfer anode and ground.

5. A gaseous discharge tube system comprising; a gas filled envelope; a cathode; a master anode having a plurality of discharge fingers for sustaining a gaseous discharge between one of the fingers and the cathode in the absence of an input pulse; two transfer anodes each having a plurality of discharge fingers, the discharge fingers of the three anodes arranged in alternate sequential arrangement equidistant from the cathode; an index anode comprising a single discharge finger for supplying an output pulse; a direct current supply circuit for the master anode supplying electrical power and causing a glow discharge between one of the master anode fingers and the cathode; a direct current supply circuit for each of the transfer anodes and the index anode supplying electrical power and causing a transient glow discharge between one of the anode fingers and the cathode when a negative pulse has been applied to the system, each of said supply circuits including a voltage divider connected across a common source of direct current, a connection between the mid-point of each voltage divider and one of the anodes, and a common resistor connected between the cathode and the negative terminal of the source of direct current; a transient control circuit causing the glow discharge to move from one anode finger to another when a negative pulse is applied thereto, said circuit including input terminals for receiving a negative pulse and applying it across the negative terminal of the source of direct current and the master anode, and capacitors connected between the transfer anodes and the index anode and ground; and an output circuit connected across the index electrode and ground for applying an output pulse to a load circuit.

NATHANIEL B. WALES, J R.

REFERENGES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,402,372 Compton June 18, 1946 2,404,920 Overbeck July 30, 1946 2,427,533 Overbeck Sept. 16, 1947 2,443,407 Wales June 15, 1948

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