US2536035A

US2536035A - Means for producing a variable number of pulses

Info

Publication number: US2536035A
Application number: US308843A
Authority: US
Inventors: Claud E Cleeton
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-12-12
Filing date: 1939-12-12
Publication date: 1951-01-02
Anticipated expiration: 1968-01-02

Description

Jan.2, 1951 c. E. CLEETON MEANS FOR PRODUCING A VARIABLE NUMBER OF PULSE-S Filed Dec. 12, 1939 2 Sheets-Shet 1 IN v5 ran Cldud E. Clea ton ATTURNE Y Jan. 2, 1951 C- E. CLEETON MEANS FOR PRODUCING A VARIABLE NUMBER OF PULSES Filed Dec. 12, 1959 2 Sheets-Sheet 2 i 97 9 85? I I I I I I I I l I I I I I l I l i I l I I I i l I I l I I I l i 94 93' 92 9 90 I l F I I I I I I l l I I I I 1 I I l I i I I I l i I l I I l I i I I I I I I l I l i L 1 I 1 1 l 1 l L I 1 E; E

99 l0 /0/ lfiZ I l I I I my I l I I I i l t /fll 7 =1 INVENTOR ATTOHWEY Patented Jan. 2, 1951 UNITED STATES ATENT OFFICE MEANS FUR PRUD UCING A VARIABLE NUMBER OF PULSLES (Granted. under the act of March 3,. 1883, as

amended April 30,. 1928.; 370 0. G. 757.)

This invention relates to apparatus forproducing groupsof pulsesof alternating curent or voltage whereby'the number of pulses in a group may be selectively predetermined.

Amongthe several" objectsof this invention are:

To provide meansfor-producing current or voltage pulses in groups of varying number:

To provide means of'thetype-specified having a plurality-of stages. that are combinable in diner q ent arrangements to give a number of pulse groupings much greater than the number of stages employed;

To provide apparatus: of the type specified wherein the number of" stages may be; varied to produce" any desired numberof pulses per group up to the .maximum of which the system is capable;

To provide simple means for predetermining the number'of pulses per group.

The manner in which the foregoing and other objects are attained will morefully' appear when the following specification is read in connection with the drawings wherein:

Fig. 1 is a: schematic drawing of one embodiment of the present invention;

Fig. 2' is-a diagram" of amultivibrator circuit wherein oscillation may be started and stopped by varying the potential on the-grid of one of the tubes;

Fig. 3 depicts-schematically a multivibrator controlled by a tube that is in turn governed by varying current in a resistor;

Fig. 4 shows schematically how a keyboard may bearranged to select the number of pulses in a group;

Fig. 5 is a diagramof a switching arrangement fcrsel'ecting thenumber of pulses in a group when it is not necessary that the change from one'numher to anotherbe quickly effected.

The'present invention comprehends, in general, amultivibrator oscillator controlled by an electronic scale-of-two? counter and an electronic switch to control" the oscillator. Any type of conntermay be utilizedinthis system if it meets the requirements of. speed and reliability.

Referring now to Fig. 1, the: tubes 5 and have their anodesMB. and 9. connected to a common anode supply It through. resistors I! and I2, respectively, and their screen grids l3. and I4 connected to the same source H! through the resistors l5-and l5, respectively. Capacitors I1 and I8, respectively, couple the anodes B and 9 to the grids 2B and H! of the tubes and 6 whereby the drop-of potential. across the resistors H and I2 when. the; respective: tubes draw current is: 811

plied to the second grid of the othertube-tohold such. other tube innon-conducting condition; Grids Iii-and Zil-are connected tothe catl iodes zl and 22 of the respective tubes through resistors 2-3 and 24;

The electronic counter is inthe' instance-depict ed in Fig. 1, madeup: of fourstages designated generally as 25-, 25; 2? and 28. All of these stages identical and the description of one applies equally to the others: Itwill be observed that stage 25 includesa first tube 29 and a second tube having anodes 2H and-32 connected to acommon supply E 5 through resistors: 33 and 3d, the second grids 35 and te being connected toxa common supply Eg through resistors 31 and 38 respectively. The anodes-31 andte are respectively connected through resistors 39 aud tsand shunting capacitors-39 and ie to the second grid (35 or 35) of the other tube. Screen grids ti andWZ areconnected to a common-supplyES. First'grids and i t have a common connection througli t5- and 46- tocapacitor'fl whereby the first grids-fitand't i arecoupled' teanode 8 of tubeB; thesaid first-gridsbeing also connected to -grou'nd' through resistor" 48-3 It will be apparent; from the foregoing that when the multivibrator tubes 5 and. l. are oscils latingr; a. negative.- P111581 will: be transmitted; through capacitor 41 to the first grids 43 .sandl44 of the tube-size; an'dl30;.sa1ppingv the flow OfiflllK- rent through the tube; that: may. be: conducting. at;

that particular: time and. causing the: other tube: in; thestagetcconduct; If. it be assumed, for purpose of illustration, that; tube; 2.91: is conducting: when. the negative. pulse: is. applied, the. flow oft currentthrough tube-.29. will. be. arrestedand; the;-

resultantrise. of: potential on anode. 3i will-heap plied throughresistonfiii and; capacitor 319." to-gridw 3% ot tnbewiiii thereby causing the tube; (iii to. be,-

come conductingawwhich inuturn. will apply. the: potential: drop. across resistor. to grid 3510i tube: 2.9. to. hold tube; 2 9. .in 1 the 1 non-econducting condition.. At the-same timehtheqpotential drop. across: resistor 3.4;: will. be transmitted through. capacitor:

tube 35 to tube 29 Will not apply a negative pulse to grids 58 and and hence the conductive condition of tubes 52 and 53 will remain unchanged.

First grids 54 and 55 of tubes 56 and 57 in stage 21 are likewise coupled to the anode 58 of tube 53 by capacitor 59 and capacitor 60 couples anode 6| of tube 5l' to first grids 62 and 63 of tubes 64 and 65 in stage 28.

Tubes 66 and 61 in switching stage 68 have their

anodes

69 and 10, their second grids H and 12 and their screen grids i3 and 74 connected in the same manner as do the tubes in stage 25 above described. However, only first grid 15 of tube 66 is coupled to the anode of tube 65 through capacitor 16, the first grid ll of tube 61 being coupled through capacitor 78 to a keying or external control source. Anode 16 of tube 61 is connected by lead 19, through parallel connected resistor 80' and capacitor 8| to the first grids 82 and 83 of multivibrator tubes 6 and 1.

It is obvious that when tube 61 is conductive, the potential drop through resistor 84 is applied to first grids 82 and 83 of the multivibrator tubes 6 and I and oscillation of the multivibrator is prevented. However, if a negative pulse be applied through capacitor 18 to first grid ll of tube 61, the flow of current through tube 61 will be arrested and the tube 66 will become conductive, the consequent rise of potential on anode being transferred to grids 82 and 83 and the multivibrator being set into operation.

-As is well known, the multivibrator operates by automatically changing the condition of conductivity of the tubes in the multivibrator circuit and hence the tube 6 will be made alternately conducting and non-conducting, with the concomitant application of a negative pulse to first grids 43 and 44 of tubes 29 and 30 each time the tube 6 becomes conducting.

A simple expedient for determining which tube in each of the stages 25 to 28 shall be conducting is to open the ground connection of one of the tubes and thus necessarily the other tube in the stage will conduct. The number of pulses in any one group is determined by the condition of the counter stages before the group starts, since this will control the number of changes in conductivity'of stage 25 necessary to go through the required series of combinations of operating conditions in the several stages to block tube 66 in switching stage 68 and thereby cause tube 61 to become conductive and stop the multivibrator.

As an example of the foregoing, let it be assumed that

cathodes

85, 86, 81 and 88 of tubes 36, 53, 56 and 55, respectively, be open circuited, thereby causing

tubes

29, 52, 51 and 64 to be in aconductive condition. As soon as the flow of current in these tubes is established the cathode circuits that were opened may be closed and the apparatus is conditioned for operation. A negative pulse is now applied to first grid Tl of tube 61 with the resultant beginning of oscillation of the multivibrator tubes 6 and I. When tube 6 passes current, a negative pulse is applied to grids 4 3 and 44 of tubes 29 and 38 and, since tube 29 has been assumed to be conducting, this tube will be blocked and tube 30 will be rendered conductive which will in turn result in the application of a negative pulse through capacitor 49 to grid 50 of tube 52 and will block tube 52 while making tube 53 conductive. The negative pulse through capacitor 59 to grids 54 and 55 of tubes 56 and 51 will change the conductivity in' stage 21 from tube5l to tube 56 but since tube 51 is now rendered non-conducting there will be no change in assaoas 4 stage 28 and the conditions of conductivity in the various stages thus set up will continue until tube 6 again conducts and another negative pulse is applied through capacitor 41 to grids 43 and 44 of tubes 29 and 30.

If the notation 29 to 36 be used to designate that tube 29 is blocked and tube 30 becomes conductive, the sequence of operation will be as follows for the set-up that was assumed to have been established:

First pulse-26 to 30, 52 to 53, 5"! to 56; Second pulse-30 to 29;

Third pulse29 to 36, 53 to 52;

Fourth pulse-48 to 29;

Fifth pulse29 to 3B, 52 to 53, 56 to 57, 64 to 65.

It is obvious that when tube 65 becomes conductive, a negative pulse will be applied through capacitor is to grid '15, that tube 61 will thus be rendered conductive and the oscillation of the multivibrator will be stopped and a group of five pulses will have been applied through output capacitor 89 to Whatever instrumentality is controlled by the pulses. For example, a transmitter may be keyed to transmit a pulse each time a pulse is passed by capacitor 85, i. e.,- each time tube 6 becomes conducting. It will be apparent from the foregoing that any number of pulses in a group, from 1 to 16, may be transmitted by suitable setting of the conductivity conditions in the tubes of the stages 25 to 28. If a greater number of pulses per group should be desired it is necessary merely to add additional counter stages to the circuit and by suitable permutations to secure the desired number of pulses per group.

If it be desirable to change rapidly the number of pulses per group, a keyboard may be arranged whereby the cathode circuits of the tubes I in stages 25 to 28 may be opened in any desired combinations. Fig. 4 shows a key arranged to open simultaneously contacts SI, 62, 93 and 94 to break the connections to ground of cathodes 85, 86, Si and 88 above described while leaving the

cathodes

95, 56, 91 and 98 connected to ground to permit the

respective tubes

28, 52, 57 and64 to conduct. It is apparent that a keyboard of sixteen keys similar to 96 may bearranged to control the sixteen combinations of cathode connection and permit instantaneously changing the number of pulses per group.

Fig. 5 shows a double-pole, double-throw switching arrangement whereby the'conductivity conditions of the tubes in the several stages may be controlled when rapid shift of the number of pulses per group is not required. With the connections of switches 66, I66, EDI and H12 as shown, when solenoid i633 is energized, contact 64 is opened and the set-up previously described is established. By suitably changing the settings of switches 9a to 162, the whole range of combinations may be attained and the number of pulses may be varied over the possible range established by the number of counter stages.

In Fig. 2 is depicted a multivibrator circuit employing triodes in the multivibrator instead of pentagrid tubes as in Fig; 1.

The anode supply M15 is connected through resistors 96 and E6? to anodes I68 and 269 of tubes HQ and Hi, the anodes I68 and 65 being respectively coupled by capacitors i IZ'and H3 to. grids H5 and N of the other tube and the grid its being connected by lead 7! to switching stage 63. V H

Fig. 3 illustrates a different method of control, using the triode multivibrator of Fig. 2. Anode (it: of tube Hi is connected to, anodesupply- Hi through anode resistor [ill or tube Hi, and grid MB of tube i ill is connectedtoisupply 510,5 through grid current limiting resistor ltd. Plate supply Ep is connected to grid I29 of tube ill; through a resistor iii and the tubes 29, 52, 55, and; derive their plate current from lead I22; tl ugh resistor l2: instead of directly from supply Consequently, when any one oi the tubes; 2:9, 5 2;, 56 S is drawing curr n tube Mlhlcv Howevenwhennone of

tubes

28,, 52 St or 655, conducting, tube M Ti becomes conduetive and the drop across resistor lil'l so reduces the poten a. on anode Hi9 that tube H t willnqtdraw cu and the multivibrator cannot o H condition of the counter stages 25 t that; oscillation of the n ultivibrator is th nor-rent the tubes as, 52, 56 or 64, draws, cur ent and cones, quently with the apparatus Qf Fig. 3, and the corn ductivity conditions as above describ d, he Hum ber of pulses per group with the device of Big, 3 will be determined exactly asin Fig. l

The wave form of the pulse is deter: inedenly by the constants of the electronic os later u d. The frequency of the pulses be anything from one cycle every few seconds to several thousand per second and is determined only by the limit of frequency of oscillation of the 1nultivibrator oscillator and the electronic counters associated with the system, Equipment embodying this invention has been operated at 33,009 cycles with a maxinnuncf 512 pulses per group. If it is desired to space the pulses closer to gether, the maximum number transmitted per group has to be decreased or the time constants of the counting circuits decreased,

The invention described herein may be manufactured and/or used by or for the Govern 3'6 of the United States of America torgovernmen purposes without the payment of any royalties thereon or therefor.

I claim:

1. Apparatus for producing a variable nu of voltage pulses in a group, comprising a mu 1 vibrator oscillator including two vacuum tubes each having a cathode, an anode, firstandsecond grids and a screen grid, anode supply means, a es e r st nce on e n each said anode and screen an to idsurn y; me n a sed: tance connecting each, saidanode to, the second grid of the other tubes; variable counter means comprising a plurality of stages, a, switching stage, each said stage including a first and a second vacuum tube each havinga cathode, an anode, first and. second grids and ascreen grid; grid, screen grid and anode supply means com,- mon to all tubes of all said stages, ares resistance connecting each said anodeto s id common anode supply, a respective resistance connecting the secondgrid of each tube in allsaid stages to said common grid supply, a resistance and capacitance in parallel connecting the anode of each tube in each said stage; to the; second grid of the other tube in the same; stage, a capacitance coupling the anode of the second tube in each counter stage to thefirstgrids, of both tubes in the next succeeding stage 'W'hfil'fi? by the potential drop across the anode resistor of a second tube when such tube passes current is impressed upon the first grids of the tubes in the said succeeding stage toreverse the conductivity conditions of such tubes, a grid leak resistance connected to thefirst grids in the tubes of each stage, a capacitance couplingtheanode of thelsecond tube in thelast counten stage tothe illstglldofthe firsttube in theswitching sta e. a capacitance coupling the anode of one of said inultivibrator tubes to the first grids of the tubes in the first counter stage, means, connecting the anode connected terminal of the anode resistance of the second tube in said switching stage to the first grids of the multivibrator tubes, meansto impress a negative potential on the first grid of the second tube, in said switching stage, and output means coupled to the anode of said one of the multivibratortubes.

2; Apparatus for producing a variable number of voltage pulses in a group, comprising a multivibrator oscillator including two vacuum tubes. a plurality of counter stages each including a first, and a second vacuum tube each of' which has an anode, a cathode and first and second grids, anode supply means, a respective anode resistance connecting each anodeto saidsupply, means to apply to the second grid of each tube the potential drop across the anode resistance of the other tube in the same stage, whereby when one tube in a stage is passing current the other tube in the same stage is held non-com ducting until changed by application of an externally derived voltage, means to apply to the first grids of both tubes in a stage changes of potential at the anode of the second tube in the preceding stage whereby to change the conductivity conditions of the tubes in each stage to which a negative potential is thus applied, means to apply to thefirst grids of the tubes in the first stage a negative potential from one tube in said multivibrator to reversethe conducting conditions of the tubes in said first stage, a switching stage including a first and a second vacuum tube each having a cathode, an anode, first and second grids, a respective anode resistor connecting the anode of each tube in said switching stage to said anode supply, means to impress upon the first grid of'the first tube in said switching stage a potential drop across the anode resistor of the second tube in the last counter stage, means to impress upon the first grid of the second tube in said switching stage an externally derived negative potential, means to impress upon the first grids of the said multivibrator tubes the drop in potential across the anode resistor of said second tube in the switching stage, and output means coupled to the anode of said one tube of said multivibrator.

3. Apparatus for producing a variable number of voltage pulses in a group, comprising a multivibrator oscillator including two vacuum tubes, a plurality of counter stages each including a first and a second vacuum tube each of which has an anode, a cathode and first and second grids, anode supply means, a respective anode resistance connecting each anode to said supply, means to apply to the second grid of each tube the potential drop across the anode resistance of the other tube in the same stage, whereby when one tube in a stage is passing current the other tube in the same stage is held nonconducting until changed by application of an externally derived voltage, means to apply to the first grids of both tubes in a stage changes of potential at the anode of the second tube in the preceding stage whereby to change the conductivity conditions of the tubes in each stage to which a negative potential is thus applied, means to apply to the first grids of the tubes in the first stage a negative potential from one tube in said multivibrator to reverse the conducting conditions of thetubes in said firststage, and switching means controlled by a negative potential drop across the anode resistor of the second tube in the last counter stage to stop said multivibrator from operating.

4. Apparatus for producing a variable number of voltage pulses in a group, a self-oscillatory device for generating periodic voltage pulses; variable counter means comprising a plurality of stages, a switching stage, each said stage including a first and a second vacuum tube each having a cathode, an anode, first and second grids and a screen grid; grid, screen grid and anode supply means common to all tubes of all said stages, a respective resistance connecting each said anode to said common anode supply, a respective resistance connecting the second grid of each tube in all said stages to said common grid supply, a resistance and capacitance in parallel connecting the anode of each tube in each said stage to the second grid of the other tube in the same stage, a capacitance coupling the anode of the second tube in each counter stage to the first grids of both tubes in the next succeeding stage whereby the potential drop across the anode resistor of a second tube when such tube passes current is impresesd upon the first grids of the tubes in the said succeeding stage to reverse the conductivity conditions of such tubes, a grid leak resistance connected to the first grids in the tubes of each stage, a capacitance coupling the anode of the second tube in the last counter stage to the first grid of the first tube in the switching stage, a capacitance coupling said device to the first grids of the tubes in the iirst counter stage whereby a negative pulse from said device changes the conductivity condition of the tubes in said first stage, means connecting the anode connected terminal of the anode resistance of the second. tube in said switching stage to apply a negative potential to said device to inhibit operation of said device when said second switching tube is conducting for the first grids of the multivibrator tubes, means to impress a negative potential on the first grid of the second tube in said switching stage, and output means coupled to said device to transfer pulses for utilization externally of said apparatus.

5-. Oscillatory apparatus, comprising two vacuum tubes each having a cathode, an anode, and a grid, anode supply means, a respective re or connecting each said anode to said supply a respective capacitor coupling eac '1 to the grid of the other tube; a third vacuum tube having a cathode, an anode, a screen grid, a suppressor grid and a control grid, means connecting the anode of said third tube to the anode of one of said two tubes, means connecting said screen grid to said anode sup-ply, a second anode supply circuit including a resistor having a high potential end connected to the cathode of said third tube and a low potential end connected to the control grid of said third tube whereby current flow in said second anode supply circuit plies a negative potential to said control grid, means connecting said high potential end to said suppressor grid and to the cathodes of both said two tubes, and a respective grid resistor connecting each grid of said two tubes to the cathodes thereof.

6. Apparatus as described, comprising a multivibrator oscillator, counter means includi plurality of stages each having two e conducting paths, a first one of said stages being connected to have the current changed from one path to the other by a negative pulse from said multivibrator, electronic switching means having two alternative conducting paths, a last stage of said counter means having One said path connected to apply a pulse to one path in said switching means, all said stages except said last stage having each one path connected to apply a negative potential to change the flow of current from one path to the other in the next succeeding stage, and means connecting the other path in said switching means to apply a pulse to stop said multivibrator when a pulse is applied to said one path of said switching means as aforesaid.

7. Apparatus as described, comprising a multivibrator oscillator including two vacuum tubes each having an anode, a third vacuum tube having an anode and a control grid, a first resistor connected in series with the anodes of said third tube and one of said multivibrator tubes, an anode supply circuit including a resistor in series with said control grid whereby when current flows in said anode supply circuit said third tube is blocked, but when no current flows in said anode supply circuit said third tube draws current and said multivibrator is blocked.

8. An apparatus for producing a group of periodic pulses in precise time relation with a controlling influence comprising periodic pulse generating means, means initiating operation of said generating means in precise synchronism with said controlling influence, counting means for the generated pulses, means terminating operation of said generating means when a predetermined number of pulses are counted by said counting means, and selectively operable means for varying said predetermined number.

9. An apparatus for producing a predetermined number of pulses in a group comprising periodic pulse generating means, a control signal, means responsive to said control signal initiating operation of said generating means to produce periodic pulses in synchronism therewith, counting means for the produced pulses, and means terminating operation of said generating means when a number of pulses equal to said predetermined number are counted by said counting means.

10. An apparatus for producing a variable number of pulses in a group, comprising an oscillator for generating voltage pulses, electronic control means connected to the oscillator to initiate and terminate operation thereof, said electronic control means including means operative responsively to a control signal to initiate operation of the oscillator in exact phase relation therewith, permuting counter means having a plurality of stages including one stage coupled to the oscillator, means conditioning said stages to interact in a predetermined combination each time a pulse from the oscillator is impressed upon said one stage whereby, after a predetermined number of pulses from said oscillator, said counter produces an output pulse, and said electronic control means including means operative responsively t0 the counter output pulse to terminate operation of the oscillator.

11. An apparatus for producing a variable number of voltage pulses in a group, comprising an oscillator for generating voltage pulses, electronic control means connected to the oscillator to initiate and terminate operation thereof, said electronic control means including means operative responsively to a control signal to initiate operation of the oscillator in exact phase relation therewith, permuting counter means having a plurality of stages including a first stage coupled to the oscillator and a last stage, means conditioning said stages to efiect interaction of certain of said stages in a predetermined combination when a pulse from the oscillator is im pressed upon said first stage, and automatically to change the combination at each successive pulse applied to the first stage until the last stage produces an output pulse after a predetermined number of pulses are applied to the first stage, and said electronic control means including means operative responsively to the output pulse of the last stage to terminate operation of the oscillator.

12. An apparatus for producing a group of periodic pulses in precise time relation with a controlling influence, comprising periodic pulse generating means, electronic control means perative responsively to the controlling influence to initiate operation of said generating means in exact phase relation therewith, counting means fed by the generating means to produce an ou put pulse when a predetermined number of pulses are counted thereby, and electronic con trol means operative responsively to the output 01 the counting means to terminate operation of the generating means.

13. The method of producing a predetermined number of periodic electrical energy pulses in precise time relation with a control signal which comprises precisionally initiating generation of equally-spaced electrical energy pulses responsively to the control signal with the first electrical energy pulse abruptly generated in exact phase relation with the control signal, counting each of the generated electrical energy pulses, and abruptly terminating generation of the electrical energy pulses when a number of pulses equal to said predetermined number are counted.

14. The method of operating an electrical energy pulse oscillation generator to produce a 10 I predetermined number of electrical energy pulses in precise time relation with a controlling influence, which comprises precisionally initiating operation of the oscillation generator responsivelyjto the controlling influence to produce periodic electrical energy pulses with the first'electrical gy pulse abruptly generated in exact phase relation with the controlling influence, counting each of the electrical energy pulses produced by the pulse oscillation generator, producing a control signal when a predetermined number of electrical energy pulses are counted, and abruptly terminating operation oi. the oscillation generator responsively to the control signal.

CLAUD E. CLEET'ON.

REFERENCES CITED i'flhe following references are of record in the file of this patent:

UNITED STATES PATENTSh Number Name Date 11,923,345 Wallace Aug."22, 1933' l-, 934,322* Osbon Nov. 7, 1933 $027,038 Hansell Jan. 7', 1936 23136532 Knoll et a1. Apr. 7, 1936 2,106,831 Dawson Feb. 1, 1938 2 ,132,654 Smith Oct. 11, 1938 2,272,070 Reeves Feb. 3, 1942- FORE'IGN PATENTS Number Country Date 355,705 Great Britain Aug. 24, 1941 OTHER REFERENCES Uffelmann: "A Thyratron Counterf, Journal of Scientific Instruments, vol. 15 (1238). pp. 222-226. Lifeshutz and Lawson: "A 'Iriodev Vacuum Tube Scale-of-Two Circuit, Review of Scientific Instruments, vol. 9, March 1938, pages.83-89.