US2792526A

US2792526A - Multi-gap cold-cathode electric discharge tubes and their use for counting and like purposes

Info

Publication number: US2792526A
Application number: US492552A
Authority: US
Inventors: Warman Bloomfield James
Original assignee: Siemens Brothers and Co Ltd
Current assignee: Siemens Brothers and Co Ltd
Priority date: 1955-03-07
Filing date: 1955-03-07
Publication date: 1957-05-14
Anticipated expiration: 1974-05-14

Description

May 14, 1957 B. J. WARMAN 2,792,526 GE TUBES AND MULTI-GAP CCLD-CATHODE ELECTRIC DISCHAR THEIR UsE FOR COUNTING AND LIKE PURPOSES Filed March 7, 1955 4 Sheets-Sheet l In ven for BLOOM/7H0 JAMES MAM/AN.

Attorney May 14, 1957 B. J. WARMAN 2,792,526

MULTI-GAP COLD CATHODE ELECTRIC DISCHARGE TUBES AND THEIR USE FOR COUNTING AND LIKE PURPOSES Filed March '7, 1955 4 Sheets-Sheet 2 /MP 7 I IVP In ventor HLOUMF/EZD JAMZJ WAfiMA/M Attorney- May 14, 1957 J. WARMAN 2,792,526

B. MULTI-GAP COLD-CATHODE ELECTRIC DISCHARGE TUBES AND THEIR USE FOR COUNTING AND LIKE PURPOSES Filed March '7, 1955 4 Sheets-Sheet 3 7 In vehlor fiZOOMF/[ZD JAMfS WARM! By M Attorney May 14, 1957 B. J. WARMAN 2,792,526

MUL'II-GAP COLD-CATHODE ELECTRIC DISCHARGE TUBES AND THEIR USE FOR COUNTING AND LIKE PURPOSES Filed March 7, 1955 4 Sheets-Sheet 4 Fig. 4A

United States hatentO MULTI-GAP COLD-CATHGDE ELECTRIC DIS- CI-DXRGE TUBES AND THEIR USE FOR COUNTING AND Lllm PURPOSES Bloomfield James Warman, Charlton,

assignor to Siemens Brothers & Co. England, a British company Application March 7, 1955, Serial No. 492,552 13 Claims. (Cl. 315=84.6)

London, England, Limited, London,

In the case of a known type of multi-gap cold-cathode electric discharge tube, a plurality of electrodes are arranged so as to form a series of electronically-coupled discharge gaps or paths, and the current fed to the gaps is of such a value that a discharge can be maintained over only one gap at any time. A discharge across one gap causes the gas in adjacent gaps to become ionised, the intensity of ionisation of the adjacent gaps falling oil as their distance from the discharging gap is increased, so that the gaps immediately adjacent either side of a discharging gap can themselves be brought to a discharging condition more readily than any of the other gaps in the tube.

In the case of one specific known form of counting tube of the type referred to, several separate cathode elec I trodes are arranged in a circle about a common anode electrode, and two equally spaced guide electrodes are provided between each pair of cathodes. The guide electrodes immediately adjacent one side of each cathode are commoned to one guide lead and the guide electrodes immediately adjacent the other side of each cathode are commoned to another guide lead. A priming electrode is placed in close relationship to one of the cathodes, and the counting action is brought about by causing a discharge to be established first between the priming electrode and the associated cathode and subsequently between this cathode and the common anode and then applying voltage pulses of suitable magnitude to the two guide leads in turn, thus causing the discharge to be transferred from this cathode to the next, in steps over the two intervening guide electrodes, the direction of transfer depending on the order in which the voltage pulses are applied to the guide leads. Since each cathode electrode is connected to a separate external connecting wire, the value of any number which the tube may have counted can be indicated electrically at any time to other apparatus, and consequently tubes of this form have a wide field of application.

The present invention arises from the realisation that in many applications of counting devices the need to indicate electricially the value of a number counted does not arise since utilisation of the numbers counted into the device may be brought about simply by counting the numbers out of the device. This is particularly the case in telephone exchange systems where it is often necessary to store a dialled digit and subsequently to control the setting of a switching device in accordance with its value. In such applications, after a digit has been counted into the counting device, the control of the apparatus to be set may be effected simultaneously with the counting out of the digit, the only external indication from the counting device required being a signal to indicate that the counting out has been completed.

One object of the present invention is the provision of a multi-gap cold-cathode electric discharge tube which ice is of economical construction and which is particularly adapted to the registration and utilisation of digits by counting the value of the digit into the tube and subsequently counting the same digital value out again.

Another object of the invention is the provision of a multi-gap cold-cathode electric discharge tube which is adapted to register a plurality of digital values whereby a single cold-cathode electric discharge tube may serve for the storage and subsequent utilisation of a number of successively dialled digits in a telephone exchange switching system.

According to one main feature of the present invention, there is provided a multi-gap cold-cathode electric discharge tube, having main anode and cathode electrodes and subsidiary guide electrodes, in which one of the main electrodes is of helical form while the other is of linear form and lies suitably spaced from the helical electrode with its axis parallel to the axis of the helical electrode, and in which the guide electrodes are associated with one of the main electrodes in such a way that a glow discharge between the main electrodes is caused to move along the helix in response to the application of counting stimuli to appropriate electrodes of the tube.

According to another main feature of the invention, a mutli-gap cold-cathode electric discharge tube, comprising anode, cathode and guide electrodes, has an anode electrode wound in the form of a continuous helix, and has at least one group of cathode electrodes comprising a main and two guide cathodes all of linear, rod-like form, these cathode electrodes being suitably spaced from and regularly disposed around the anode helix with their axes lying parallel to the axis of the helix.

According to yet another main feature of the invention, a multi-gap cold-cathode electric discharge tube, comprising anode, cathode and guide electrodes, has a cathode electrode wound in the form of a continuous helix, and has at least one group of anode electrodes comprising a main and two guide anodes all of linear, rod-like form, these anode electrodes being suitably spaced from and regularly disposed around the cathode helix with their axes lying parallel to the axis of the helix.

Cold-cathode electric discharge tubes arranged in accordance with either of the last-mentioned two features and with suitable potentials applied to the main anode and cathode electrodes, may be operated by the application of successive stimuli to the guide electrodes, such stimuli causing the glow discharge to move in steps round the turns of the helical electrode. As many linear elec trode groups as required may be situated around the helical electrode, the greater the number of such groups provided the smaller being the deflection per step due to the counting stimuli.

According to a further main feature of the invention, a multi-gap cold cathode electric discharge tube, comprising anode and cathode and guide electrodes, has its cathode and the guide electrodes in the from of a multi-wire helix wound in the manner of a multi-start screwthread, the helix being disposed in spaced relation to an anode or anode assembly in such a way that discharge gaps are formed between the anode or anode assembly and points on the helix opposite said anode or assembly. Cold cathode electric discharge tubes arranged in accordance with this feature and with suitable potentials applied to the main anodes (which may be of linear or rod-like form) may be operated by the application of successive stimuli to the guide electrodes. In this case, however, the application of such stimuli causes the discharge to move in steps from turn to turn of the helix.

According to yet another feature of the invention a multi-gap cold cathode electric discharge tube comprising anode and cathode and guide electrodes has its cathode and the guide electrodes in the from of a multi-wire helix and 6 will have the electrodes connected to lead-in similar other illustrated-in Big. 3.

wound in themanner of a multi-startscrew, thread and a plurality of anodes of linear form lying parallel with the axis of the helix and spaced therefrom to provide discharge gaps with the Wires of the helix, each of the anodes forming with the helical cathode and guide electrodes which it faces an independent counting section of the tube whereby the values of a number of successively received digits may be counted and stored. With a cold cathode electric discharge tube arranged according to this feature the value of a received digit may conveniently be registered as the number of helicalturns on the cathode helix separating the glow discharges between'the cathode and two'of the anodes. Registration in thismanii'er can be effected by arranging that a glow discharge isstepped along one counting section of the'thbe in "fespoii'seto the impulses of a re'ceived'digit' and that a'f irtlier glow discharge is initiated atthe start of a nother coun't' g'se'ction of th e tube prior tothe receipt of a following'fdig'it. The glow discharge markingthe end of 'any one 'dig'it'hiay also mark the beginningof the' nextfdigih' the impulses of each digit adva'ncingall the existing grow i discharges along the main helix in step with their spacings preserved.

'An advantage of this arrangement is that it automatically forms the digital values registered into a queuealong the length of the helix "and so permits their utilisatibnin'the order of recepit Withoutthe need ifor any' distributors to couple the linear electrodes in aparticularorderito 'the utilisation equipment. With this'method of "counting receiving distribution ineansare required to control the initiation of the glow discharges in the various counting sections of the tube as digits are received. 7

According to still anotherfeature of the invention receiving distribution means as referred to above'are provided within the tube itself and comprise a digit counting helixwhich is continuous with the main and guide helices 'in the counting part of the tube but the guide electrodes in the distribution part of thetube are electrically separate from the guide electrodes in the counting partfof the tube, signals applied to the guide electrodes in the distribution part of the tube causing the glow discharges in that part of the tube to advance one turn along the main helix so that one of the discharges appears at the commencement of the counting part of the tube.

Thepreviously mentioned and other featuresof'the inventionareexemplified in the specific embodiments now to be described with reference to'the accompanying drawings.

' t I ifferent embodiments. of invention "nowi fbe described by way'io'fexample with, refere'nceto the accompanying drawings. In the drawings Pig. 1, 'show'sidiagrammatically a gas-filled 'multi-gap cold 'c'athodejelectric discharge'tube with a' helical cathodefandf'r 1A is "ana ram sue anode and guide'electr'odes' and Fig. i

Fi 1 along'fth'e line cross-sectional view of the tube of A- A. Fig. 2 shows schematically a 'c'ircuitari'angement for use with a tube asillus'trated in Fig. 1. Fig. 3 shows a cold. cathode tube with a rod-like anode andfh'elical cathode and guide, electrodes. Fig. 4 showsdi'agr'amrnatically a cold cathode tube with a plurality of rod like anodesand helical cathode and guide electrodes and Fig.

"4A is a diagrammatic cross-sectional view of the "tube of Fig.4 along the line BB. Fig. 5 shows schematically a a circuitarran'gement for use with a tube as'illustr'ated n Fig 4. Fig. 6 shows diagrammatically a cold cathode tube similar to that shown in Fig. 4 but in which 'r'eceivting distribution means. are provided within the ftubeit'self and Fig. .7shows schematically use with a tube as illustrated in Fig. 6.

. Th'etubeswith electrodes arranged as illustrated in Pigs. L flA sealed into the tube at one or both ends in'a'rhahner 7 Reference should now be had to Figs. 1" and lAs 'lhe tub e comprises an envelope 1. preferably" of glass" into which are sealed leads to'the 'sev'eraf'electro'des"and in 75 a circuit arrangementffon greases which is supported, a former] .of insulating material, suitably glass, on which the helical cathode 3 is wound. The former may be cylindrical with a helical groove in its surface to accommodate the wire of the cathode. Spaced from the surface of the helical cathode are three other electrodes, the anode 4, and two

anodic guide electrodes

5 and 6. The anode and thejguide"electrodes'are stilt wires or rods which maybe self sup'portingor anchored to the wall of the tube, l ying parallel to the axis 'of the helix. The spacing 011 these electrodes is equiangular with respect to the axis of the helix and the spacihg from the surface of the helix such as to provide gaps across which glow discharges may be set up, the length of the gaps being determinedinteralia by thepressu reof the gas filling of the tube, and the voltages to be applied to the electrodes. The tube is filled with an inert gas or a mixture of gases. The helical cathode is severed so as to form two parts, a main'ca'thode' 7 :ancl'an output cathode 8, the latter being formed by "anend turn of the Y condensers C1 and C2 and reversing contacts RV connected to the guide electrodes Sand o'and'r'esistancesconnectedto the several electrodes of the tube (except the anode thereof). The'tube electrodes are connected as follows. The main cathode 7 is conectedover load resistance R3, contacts SC and current limiting resistance R- i to earth and the output cathode is'connected over'resistance R5 and the current limiting resistance R4 to earth and also over condenser C3 to wire UClea'ding to a utilisation circuit which would be a circuit in which use is made or" the impulses stored'in' the tube and subsequently' counted out. The anode 41's connected over contacts AC directly to a source of positive'potential indicated as a positive battery with its negative pole earthed and the anodic guide electrodes Sand 6 are'conne'cted over resistances R1 and R2 respectively to a similar or the same source of positive potential. The

guide electrodes

5 and 6 are also connected over reversing contacts RV and condensers C1 and C2 respectively to wires P1 "to count'them out. For the purpose 'of operating the tube the anode is connected to the source of positive potential; for example by closure of contacts AC', whereiipoh a" glow discharge will be set up I between the anode '4 and the cathode 8. To 'commencecountin'g, contacts over wires Pland P2. Each impulse to'be' counted gives SC are closed and impulses are fed to the guideelectrodes rise to pulses on these wires as follows, first a positive pulse on wire P1 and a negative" pulse'on wire P2 followed by a negative pulse on 'wire P1 and a positive pulse on'wire P2. The first negative pulse is fed to electrode 6 and the first positive pulse isjfed to'electrode5 resulting in an increase in positive potential on electrode 5 and a decrease in potential on electrode 6. V The area of maximum glow discharge is shifted along'the cathode 7 from the'fmain anode 4 to the anodic'guide electr'ode 5. The following pulse of reversed polarity results inanincrease inpositive potential onpelectrode 6 and a decree e in potential on electrode Sand the glow discha igeisshifted from the anodic' guide electrode 5 to 'the anodic "guide electrode 6. Upon the termination' ofihe pulse "the the guide electrodes revert to their normal glow discharge is now shifted 'fromjthe' anodic guide electrode 6 to the main anoded. aresultof the receipt area ae glow discharge has moved round thecathode helix, in a clockwise manner looking at the lower end of the tube of Fig. 1, from the cathode 8 to the first turn on cathode 7 and one impulse will have been counted. Further impulses are counted in a similar manner and cause the glow discharge to travel round the helix from one turn facing the anode to the next until at the end of the impulsing the discharge appears between the turn on cathode 7 corresponding to the number of impulses counted and the anode 4. To count out the impulses the reversing contacts RV are operated and further sets of pulses are fed over wire P1 and P2 and at the same time impulses are delivered to the utilisation circuit. This time, owing to the operation of contacts RV the pulses to the guide electrodes are fed in the opposite order so that the first negative pulse on wire P2 reduces the potential of the anodic guide electrode and the first positive pulse on wire P1 increases the potential of the anodic guide electrode 6 thereby causing the area of maximum glow discharge to shift along the cathode from the main anode 4 to the anodic guide electrode 6 and the cathode, i. e. in counter-clockwise direction looking at the lower end of the tube of Fig. 1. The following increase of potential on electrode 5 and decrease of potential on electrode 6 will cause the discharge to shift from electrode 6 to electrode 5 and when the pulse ceases, to the anode 4 whereupon the discharge will appear between the anode and one turn on the cathode 7 nearer the cathode 8 and one impulse will have been counted out. The same result may be had without the reversing contacts by arranging for the pulses to be fed to the wires P1 and P2 in the reverse order, that is to say a negative pulse first appears on wire P1 and a positive pulse on wire P2 followed by a positive pulse on wire P1 and a negative pulse on wire P2. Continued feeding of pulses to the wires P1 and P2 and to the utilisation circuit will shift the glow discharges backwards, with respect to the countingin direction, until a discharge is caused to appear on cathode 8 in consequence of which a signal will be transmitted over condenser C3 and wire UC to the utilisation circuit to stop further impulse transmission and to terminate the counting out process.

In an alternative form of the tube shown in Fig. l the anode may be formed as a helix with a separate output electrode at one end and the cathode and guide electrodes may be of rod-like form. In such an arrangement the guide electrodes would be cathodic instead of anodic as in Fig. 2.

In the arrangements so far described the operation of the tube may be arranged to be of a cyclic nature by arranging a separate or priming electrode at the upper end (in Fig. l) of the tube and providing separate means to accept a signal from the output electrode and to feed a corresponding pulse to the priming electrode to cause the discharge to transfer immediately to the priming electrode in readiness for continued counting action. Reference will now be had to the multi-gap tube shown in Fig. 3. In this figure the tube 1 is shown broken to indicate a greater length than that actually shown. Corresponding parts have been given the same designations as in Figs. 1 and 1A. The cathode is a helix shown in thick lines with its left hand turn severed at 9 from the remainider to form a single turn output cathode 8 separate from the multi-turn main cathode 7 but forming a continuation of the helix. The

guide electrodes

5 and 6 are also helices wound on former 2 with the cathode helix to provide a multi-wire helix in the manner of a three-start screw thread so that the turns of the helices appear from left to right as output cathode 8, guide electrode 5, guide electrode 6 main cathode 7, guide electrode 5 and so on. The

' guide electrodes in this embodiment are cathodic. The

anode 4 is a stiff wire lying parallel with the axis of the multi-start helix and supported by metal members embracing the forrner 2 on which the helix is wound and suitably spaced from the surface of the helix to form gaps with the wires of the helix. In the tube shown the anode 4, cathode 7 and guide electrode 6 are connected to leadin wires sealed into a pinch at the right hand end of the tube and the cathode 8 and guide electrode 5 are connected to lead-in wires and sealed into a pinch at the left hand end of the tube. The number of turns on the main cathode will be determined by the number of impulses to be counted. For the operation of the tube pulses are applied to the guide electrodes in such a manner that for each impulse to be counted a negative pulse is applied to electrode 5 and a positive pulse to electrode 6 followed by a positive pulse to electrode 5 and a negative pulse to electrode 6 to cause a glow discharge to transfer from a cathode turn first to the adjacent turn of electrode 5 and then to the adjacent turn of electrode 6 and when the pulses cease the discharge is caused to transfer from the turn of electrode 6 to the adjacent cathode turn. An initial discharge is first set up by a pulse fed to the output cathode 8 from which it is transferred to turns on the main cathode 7 as described above and appears finally when a digit has been counted, between the anode and the cathode turns corresponding to the number of impulses counted. Counting out is performed in a similar manner to that described in connection with the tube of Fig. l, pulses being fed to the guide electrodes in the reverse order to that for counting in to cause the discharge to be transferred back to the output cathode. Simultaneously with the pulses fed to the guide electrodes impulses are fed to the utilisation circuit connected to the output cathode and the return of the discharge to the output cathode gives a signal to the utilisation circuit to stop further impulse transmission and to terminate the counting out process.

A modification of the tube shown in Fig. 3 will now be described with reference to Figs. 4 and 4A. In these figures, which are diagrammatic, the tube is provided with a cathode helix comprising a main cathode 7 and an output cathode 8,

helical guide electrodes

5 and 6 wound with the cathode helix in the manner of a three start screw thread, the whole forming a multi-wire helix, and a plurality of anodes in the present example five in number. There is also an independent priming cathode. The anodes are designated 41, 42, 43, 44 and 45 and are in the form of stiff rods spaced about the axis of the helix and at a suitable radial distance from the surface of the helix to form discharge gaps therewith. The cathode helix is shown in thick lines and beyond, that is to the left of the output cathode 8, is a home turn 10 forming a continuation of the helix but separated from the output cathode 8. The turn 10 is connected internally or externally with the main cathode 7. The priming cathode 11 which is at the opposite end of the tube to the output cathode is in the form of a ring or disc from which fingers 12 project towards the ends of the anode rods forming gaps therewith. It is to be understood that the several electrodes within the tube are connected to lead-in wires suitably sealed into the tube which is preferably of glass. The electrode arrangement shown is suitable for a tube to count and store the impulses of four digits and for this purpose there would be 43 turns of the cathode helix and 42 turns of each of the guide electrode 'helices to cater for digits on a decimal basis as ordinarily used in telephone systems. Each anode together with the cathodic helices forms in effect a separate counting section. The operation of the tube is started by applying a suitable potential to a selected anode and simultaneously feeding a negative pulse to the printing cathode to cause a discharge to take place between that cathode and the selected anode, the other anodes inactive at the time. Consequent on the appearance of a discharge between the priming cathode and an anode, potential change in the priming circuit causes the discharge to transfer from the priming cathode to the first turn of the main cathode 7. Once an anode is supporting a glow discharge to the main cathode the anode voltage Q prising two parts, a counting part and a distributor part, the latter being the right hand end and including the four additional cathode turns. Between the cathode turn in the counting part of the tube which commences at the fifth cathode turn designated 71 and extends to include the home turn 10 are the guide electrodes and 6 wound as helices with the cathode turns in the manner of a three-start screw thread to form a multi-wire helix and the first four turns of the cathode are wound with two

other wires

13 and 14 and herein referred to as distributor guide electrodes to form another multi-wire helix, the

electrodes

13 and 14 being separate from the

guide electrodes

5 and 6. There are five rod-like anodes 41-45 which extend throughout the counting part of the tube four of the anodes extending for different distances into the distributor part of the tube. Thus, anode 41 terminates opposite the 5th cathode turn, anode 42 terminates opposite the 4th cathode turn and so on. There is also a priming cathode 11 as in Fig. 4 but with fingers 12 extending for different lengths to form priming gaps with the ends of the several anodes. In response to a negative pulse fed to the priming cathode discharges appear at all the priming gaps and on the termination of the pulse transfer to the turns of the main cathode op posite the ends of the respective anodes. As before, each anode together with the cathodic electrodes forms a counting section. Discharges between anode and cathode are transferred by action of the guide electrodes as in the previous example. The impulses of the first digit will effect transfer of the discharge between anode 41 and cathode turn 71 to a point along the main cathode corresponding to the number of impulses received. At the end of the impulse train successive pulses will be fed to the distributor guide electrodes to transfer the discharges on the first four cathode turns one turn forward, bringing the discharge on anode 42 to turn 71. The impulses of the second digit are advanced along the cathode and at the same time the discharge representing the first digit is correspondingly advanced. At the end of this and of each successive digit the discharges in the distributor part of the tube are advanced one cathode turn and the impulses of each digit transfer the discharge appearing on cathode 71 together with previously set up discharges in the counting part of the tube along the main cathode until the impulses of the last digit have been counted and stored. When this occurs there will be five discharges present, four discharges between different turns in the main cathode and the several anodes and one between turns 71 and anode 45, the spacing between the several discharges along the main cathode corresponding to the impulses in the several digits counted. The stored impulses are counted out exactly as described in connection with the preceding example.

Circuit arrangements suitable for operating the tube of Fig. 6 are shown in Fig. 7. In general, these are similar to those of Fig. 5 but earth potentials are not applied to the anodes and removed from them in turn as all the anodes are active when the tube is taken into use. As in Fig. 5 the anodes are connected over load resistance such as resistance R41 to a source of positive potential, main cathode 7 is connected to earth, output cathode 8 is connected over resistance R4 to earth and over condenser C3 and wire UC to a utilisation circuit and priming cathode 11 is connected over condenser C4 and wire NP to which negative pulses may be applied and also over resistance R11 to earth. The devices IS and LS are similar to the device IS in Fig. 5 and device ED generates successive positive and negative pulses at the end of each impulse train received by it over wire IMP. Device 15 generates successive positive and negative pulses in response to impulses to be counted received over wire IMP and device LS generates similar pulses from a source of locally generated impulses. It is to be understood that change over arrangements will connect the guide electrodes 5 and.

taken into use a negative priming pulse is fed over wire .NP to the priming cathode 11 and discharges are set up between this cathode and the ends of each anode. When the priming pulse terminates these discharges transfer to the turns of the main cathode adjacent the ends of the respective anodes, the discharge on anode 41 appearing on cathode turn 71 and the discharges on the other anodes appearing on cathode turns 4, 3, 2 and 1. The first impulse train to be counted. is transmitted over wire IMP to the device IS which, as before described delivers successive positive and negative pulses at each received impulse to the

guide electrodes

5 and 6 to cause the discharge on anode 41 to advance along the counting part of the tube. At the end of the impulse train successive positive and negative pulses are transmitted from the device ED to

distributor guide electrodes

13 and 14 to cause the discharge on the first four cathode turns to advance one cathode turn so that the discharge on anode 42 now appears on cathode turn 71 and the discharges on the anodes 43-45 appear on the 4th, 3rd and 2nd cathode turns respectively. The impulses of the second impulse train give rise to the pulses on

guide electrodes

5 and 6 to advance the first and second discharges between their respective anodes and the turns of cathode 7 so that the spacing between the first and second discharges corresponds to the number of pulses in the first received impulse train. At the end of the impulse train device ED feeds pulses to the

distributor guide electrodes

13 and 14 to advance the discharges on the 4th, 3rd and 2nd turns to the 5th, 4th and 3rd turns respectively. Successive impulse trains are counted in a similar manner to that described for the first and second trains, all the discharges moving along the tube between their respective anodes and the cathode 7, the discharges in the distributor part of the tube being advanced one cathode turn at the end of each impulse train. At the end of the fourth impulse train there will be spaced discharges between the cathode 7 and anodes 41-44 and a discharge between cathode turn 71 and anode 45. For the utilisation of the counted impulses, pulses derived from locally generated impulses in the circuit LS are delivered to the

guide electrodes

5 and 6 and the discharges are transferred along the tube towards the output cathode where they give rise to a signal over wire UC to indicate the end of a digit and are then transferred to the home turn as described in connection with Fig. 5.

What is claimed is:

1. A gas-filled multi-gap cold cathode electric discharge tube having main anode and cathode electrodes one of which electrodes is in the form of a helix and the other of which is of linear form lying parallel with the axis of the helix and spaced therefrom to form discharge gaps with the surface of the helix and guide electrodes ar ranged to provide discharge gaps with one of said main electrodes and positioned so that on the application to them of stimuli a discharge between the main electrodes will move along the helical electrode.

2. A gas-filled multi-gap cold cathode electric discharge tube having a helical cathode, an anode and guide electrodes all of linear form and lying parallel with the axis of the cathode helix and spaced therefrom equiangularly with respect to said axis to provide discharge gaps with the cathode helix, the guide electrodes being so positioned that on the application to them of stimuli at discharge between the anode and cathode will move round the helix along the tube in a unidirectional manner.

3. A gas-filled multi-gap cold cathode electric discharge tube having a helical anode, a cathode and guide electrodes all of linear form and lying parallel with the axis of the anode helix and spaced therefrom equiangularly with respect to said axis to provide discharge gaps with the anode helix, the guide electrodes being so positioned that on the application to them of stimuli at discharge tube for' the-counting .heli-cal electrode being. a main .theinfiuence of stimuli applied -helix along the :tube in a unidirectional manner.

4;'-Agas-filled' multi-gap coldcathode electric'discharge -tube having helical cathodic electrodes aranged in the manner of a"'multi-start'screw thread and an a'n'ode' of linear form lying' parallel with the axis' of the helical electrodes" and' spac'ed'therefrom to provide discharge gaps with the surfaces of the helices, one of the=helical elec trodes being a main cathode and the other helical electrodes being 'guide electrodes" for causing a discharge between the anode andthe main cathodehelix to move along the helix in a unidirectional mannerfrom one main cathode-turn to the next under' the influence of-stimuli applied to the said guide electrodes.

5. A gas-filled multi-gap'cold cathode electric discharge and storing of impulses of a'plurality of digits having helical cathodic electrodes arranged in th'e manner of a multi-start screw thread and a plurality i of anodes in number one more than the number of digits to be stored and of linear form lying parallel with the axis of the helical electrodes and spaced therefrom with :respect to the said axis to provide discharge gaps with the suraces of the helices, one of the helical electrodes eing a main cathode and the other helical electrodes being guide electrodes for causing a discharge between the main cathode helix and an anode to move along the .helixin a unidirectional manner from one main cathode turn to the next under the influence of stimuli applied to the said guide electrodes.

6; A gas-illedmulti-gap cold'cathode electric discharge tube for the counting and storing of impulses of a plurality of digits having helical cathodic electrodes ar ranged in the manner of a multi-startscrew thread one cathode and the other helical electrodes being guide electrodes for causing a discharge between the main cathode helixzand an anode to move along the helix in a unidirectional manner under to the. guide electrodes .7 and a plurality ofwanodes in number one morethan the number. of digits to be stored and of linear. form lying parallel with the axis of the helical electrodesand spaced withrespect to said axis to provide discharge 'gaps with thesurfaces of the helices, said tube comprising a count- ..ing partand a distributor part, the main cathode extendlingthroughout both parts and the-said guide electrodes extending only throughout the counting part, further helical guide electrodesalsoforming with the main cathode helix a multi-wire helix arranged in the manner of a multistart screw -thread of "equal. diameters extending only throughoutthe distributor part of. the 'tubethenumber of turns of the. main cathode helix in the distributor part (ofthe tube correspondingto the numberof digits to be stored by the tube,.the anodesextending throughout'the counting .partofthetube and-into the distributor part for varying distances .such that each :anode terminates opposite a differentturn of themain cathode.

7. A. gas-filled. multi-gap cold cathode electric discharge tube according to claim 1 in which the helical electrode comprises a number of turns forming a main helix and a single turn at one endthereof being a continua tion of the main helix but separated from it to form an output electrode.

8. A gas-filled multi-gap cold cathode electric discharge tube according to claim 5 in which the main cathodehelixcomprises a numberofturns forming a main :helix and two turns at oneend thereof being a continuation of the main helix but. separated from it and. from nnc.i another,sthe.turnsnearer the main helix forming an -output cathode and the turn more remote from the mainfihelixt-be'ing' connected in a; circuit that will. sustain a .piu'ral'ity'of discharges between said moreremote turn Land-the. anodes.

" 9. frlgas-filled multi gap cold cathodef-electricdisaccording to' clairn 5 in which at: the end'of 12 the. tube Iadjacent that end. ;of the helix :at which..a.;discharge istobe initiated is a priming: cathode oficircular form co-axial With the helix and with projections zextending into the tube'and'opposingthe ends of the anodes.

l0; A 'gasdilled multi-gap cold cathode electric discharge tube for the counting andstoring-of impulses having a cathode in the form of a helix, an anode of linear form lying parallel with the -axis of the helix and spaced therefrom to form discharge gaps with the surface of thehelix and -guide-electrodes and meansfor setting up an initial discharge between the anode and'one end. turn of the helix; means forfeeding pulses to the guide electrodes in-one'order of succession to transfer -=said initiahdischarge to B."IUIH-OI1 the helix-corresponding tothenuh1ber-of impulses to be counted and stored and means for feeding pulses to the guide electrodes in the opposite order of succesion to'transfer the discharge from the turn to which it was brought bysaid 'firstmentioned pulses back to said end turn.

11. A gas-filled multi-gap cold cathode electric discharge .tube for the counting and storing of impulses provided with electrodes according to..claim 10 in which the helix comprises a number of turns forming a main helix and at one end thereof a single turn forming a continuation of the main helix but separated from it comprising an output electrode connected to a utilisation circuit and in which during the feeding ofpulses to the guide electrodes in said opposite direction impulses are fed in step with said pulses to the guide electrodes and the return .of the discharge to saidendturn provides a signal to the utilisation circuitthat counting is to cease.

. 12. A gas-filled multi-gap: cold cathode electric -dis- .charge'tubefor the counting and storing of impulses of each of a plurality of digits provided with electrodes according to ciaim 5 in which the cathode helix-comprises a number of turns forming a main helix and at :one end thereof a single turn forming a continuation of the main helix but separated therefrom comprising an ouput cathode to which is connected at utiiisation'circuit and means for setting up at the commencement ofze'ach digit tobe counted at discharge between he main helix and a selected one of the anodes, means operative at the end of .each digit for selecting theanodes in turn and means for feeding pulses to the guide electrodes to transfer discharges between the main helix and the several anodes to positions along the main-helix corresponding-to the impulses in each digit to be counted and means for-feeding further pulses to the guide'electrodes and at the same time feeding impulses to the utilisation circuit to transfer all the discharges to said output cathode, the arrival-of a discharge on said output-cathode giving 'rise'to a signa l to the utili'sationcircuit that counting of the digit represented by the discharge is to cease.

adjacent ends of the several anodes in the distributor part of the tube and a discharge .betweenthefirst turn in. the r counting. part of the. tube andP-the .zadjacentend; of an anode: and means for feeding pulses to. the. guide electrodes -..in. the countingpart. of the .tube to .transfer...discharges therein along the main helix to positions corresponding to the impulses to be. countedand.meansioperativeattheend of each. digit: for feeding pulses: to; the, guide electrodes inthe. distributor part of the. tube toadvancethe discharges in that part of the tube to the: next main helical turn nearer T the countingpart of the tube: and means :for feeding pulses 2,792,526 13 14 to the guide electrodes in the counting part of the tube and References Cited in the file of this patent for feeding impulses in step therewith to the utilisation cir- UNITED STATES PATENTS cuit to transfer all the discharges to the output cathode, the

arrival of a discharge on the output cathode giving rise 252O171 Reeves 1950 to a signal to the utilisation circuit that counting of the 5 EI N PATENTS digit represented by that discharge is to cease. 639,841 Great Britain July 5, 1950