US3079588A

US3079588A - Transistor switching devices in a gas tube coincidence matrix selector

Info

Publication number: US3079588A
Application number: US768640A
Authority: US
Inventors: Burstow Pierre; Monin Claude
Original assignee: Compagnie Industrielle des Telephones SA
Current assignee: Compagnie Industrielle des Telephones SA
Priority date: 1957-11-08
Filing date: 1958-10-21
Publication date: 1963-02-26
Anticipated expiration: 1980-02-26

Description

Feb. 26, 1963 P. BU RSTOW ETAL TRANSISTOR SWITCHING DEVICES IN A GAS TUB COINCIDENCE MATRIX SELECTOR Filed Oct. 21, 1958 +V a (V INVENTORS PIERRE BURSTO w CLAUDE MON/N ilnited states Patent 1 3,679,588 TRANSISTQR SWITCHENG DEVECES IN A GAS TUBE CDINCIDENQE MATRIX SELECTOR Pierre Burstow, Paris, and Claude Monin, Villennes-sur- Seine, Seine ct Oise, France, assignors to Comnagnie l'ndustriellc des Telephones, Paris, France, a French corporation Filed (Pct. 21, 1958, Ser. No. 768,640 Claims priority. application France Nov. 8, 1957 7 Claims. (Cl. 340-166) The present invention relates to a controlling device which can be used especially in electronic switching and which permits of controlling by static means the transmission of an alternating current from one point to another.

Devices of this type are already known, for example from French Patent 1,126,635, filed on May 21, 19-55, and the French Patent 1,160,892, filed by applicants on November 23, 1956. However, in these devices, the alternating current, in passing from a point .A to a point B, must flow through two electrochemical condensers of relatively high capacitance which do not, in some cases, have suificient robustness, especially in the case of equipment which has to undergo shocks.

The device according to the invention is characterised by the fact that it comprises a transistor disposed between the two points to be connected, the transistor being rendered conductive or non-conductive for alternating current as required, in accordance with the potential connected to its base, which latter may be connected, in the case of a pnptype transistor, either to a positive polarity of higher absolute value than the emitter, or to a negative polarity in relation to the emitter. In order that the point connected to the base of the transistor may thus change polarity as required, it is connected on the one hand to a positive polarity through a resistance and on the other hand to the anode of a gas tube having an auxiliary anode.

When the gas tube is fired, a current passes therethrough which produces a voltage drop across the resistance and varies the potential of the base to a sufficient extent to render the transistor conductive. The gas tube may lire under two conditions corresponding to two controls applied, one to the cathode and the other to the auxiliary anode.

The device according to the invention is particularly interesting when employed in a selecting matrix comprising circuits disposed in horizontal lines and circuits disposed in vertical lines crossing the said horizontal lines and for effecting the connection between any horizontal line and any vertical line by means of a connecting point device disposed at each crossing of a horizontal line and of a vertical line, the emitter and the collector or" the transistor each being connected to a separate line and the anode of each gas tube being fed through a separate resistance from a voltage source common to the anodes of a single line, the auxiliary anode of each tube being fed through another separate resistance and the separate resistances of the auxiliary anodes of the tubes of one horizontal line being connected to a common point which is in turn connected to a switch for the application of voltage, the cathodes of the tubes of one vertical line being connected to a common point which in turn is connected to a common resistance in series with a switch for the application of voltage, the connection between one horizontal line and one vertical line being efiected by closing of a switch of the horizontal line and by a switch of the vertical line, which latter two operations result in the firing of the tube situated at the crossing point of the two lines, while the operation of the tube is maintained as long as the cathode switch re- "ace mains closed, and no other tube of the same vertical line being able to become operative as long as the tube in operation itself remains operative.

Further features and advantages of the invention will become apparent from the description thereof which is herinafter given with reference to the accompanying drawings, which show by Way of example constructional forms of the device according to the invention.

FIGURE 1 illustrates diagrammaticallly a simple link according to the invention between a point A and a point B.

FIGURE 2 illustrates a modification of FIGURE 1.

FIGURE 3 illustrates a matrix comprising m lines and q columns adapted to establish mq links.

In FIGURE 1, there are shown two points A and B between which it is desired to permit or interrupt the flow of an alternating current when required, without using movable contacts. The point A may be connected to earth by a switch K and is connected at C to the emitter of a transistor T. The point B is connected at D to the collector of the same transistor and the base of the said transistor is connected to a point B through a resistance Rb. The point E is connected on the one hand to the positive pole of a direct voltage source +V through a resistance W and on the other hand to the anode of a gas triode L. The cathode of the triode L is connected to the negative pole -V of a direct 'voltage source through a resistance R and a switch V. The auxiliary electrode of the triode is connected to the positive pole +Vs of a direct voltage source through a resistance r and a switch H. It is therefore necessary, for firing the tube L, to apply voltage simultaneously to the auxiliary electrode and to the cathode, that is to say, to close the switches H and V. The device operates as follows: in the case of a junction transistor of the pup-type it is necessary for its emitter to be posittive in relation to the base in order that it may be debIOcked. When the triode is not fired, the base is conneoted to a positive potential in relation to the emitter. Since the latter is earthed, the transistor is blocked. If the triode is fired by closing of the switches H and V and if the switch H is thereafter opened, the triode continues to operate and a current flows therethrough between the anode and the cathode. The voltage drop due to this current across the resistance W is suflicient for the potential of the point B to fall below that of the point A if the values of the polarities and of the resistances are appropriately chosen. At this instant, since the transistor is deblocked, it provides for collecting at its collector substantially the same alternating-current which has been applied to the emitter. In order to block the transistor again, it is sufiicient to interrupt the current flowing through the triode by opening the switch V, the point B then returning to a positive potential in relation to the emitter.

FIGURE 2 is a modification of FIGURE 1 and does not dififer therefrom in its principle, but solely in the manner in which the gas triode is struck. The base of the transistor is always connected to the point E through the resistance Rb and the point E is always connected on the one hand to the positive potential +V through the resistance W and on the other hand to the anode of the valve L. However, the cathode is here connected, without the interposition of a switch, on the one hand to the negative potential -V through the resistance R and on the other hand to the electrode of a condenser P whose other electrode is earthed. The auxiliary electrode of the triode L is connected to a point G comprising two symmetrical links, each of these links being formed by the connection of the point G to a positive polarity +Vs through a resistance d and a switch H. Connected to the point I, situated after the resistance d and bet re the switch H, is a resistance e, the other end of which is at the negative potential Vs. The operation is as follows:

.the gas triode is fired merely by action on the auxiliary electrode, since the anode and the cathode comprise no switches and are connected to fixed polarities +V and -V respectively. if a single switch H is closed and the value of the resistance e is made small in relation to (I, the point G reaches a potential substantially equal to 7 .stop'the operation, the switch Kc is operated and applies to the condenser P the voltage u existing between the point P and earth. The condenser P is charged with a quantity of electricity Q=P.u (P representing the capacitance of the condenser). This quantity of electricity may be suilicient to produce the immediate extinction of the gas tube (if P is suificiently high).

FIGURE 3 illustrates a matrix comprising in horizontal rows and q vertical columns, only the rows X X and X and the columns Y Y and Y having been drawn. Any rows such as X can be connected to any column such as Y; by the operation of a transistor T situated at their crossing point if therappropriate voltages for producing the firing of a gas triode L have been applied as seen with reference to FIGURE 1. Each crossing point (or each connecting point) is thus formed in accordance with FIGURE 1, in which the arrow fH corresponds to the multiplying of the emitters on a common horizontal row, the arrow v corresponds to the multiplying of the collectors on a common vertical column, the arrow at the point P of the cathode corresponds to the multiplying of. a common resistance such as R c for feeding the cathodes ofa common column by the potential -V and finally the arrow V corresponds to the multiplying of the anode voltage V at the separate resistances W 1, W l t W this multiplying being effected by columns (or by rows). The voltage Vs is distributed by horizontal rows by means of the switches H H H The operation is as follows: it will be assumed that it is necessary to establish a call between the row X and the column Y the wire X having previously been earthed. It is therefore necessary to render conductive the transistor T situated at the crossing point. The anode voltage V having been applied to the various separate resistances W W W of the first column, voltage is applied to the tube L In order that the tube may be struck, two other conditions must be satisfied, one being reprezsentedby a horizontal control and the other by a vertical :control. The horizontal control consists in closing the switch H for applying the potential Vs to the auxiliary anode of the tube L through the resistance r It will be seen that this potential Vs is at the same time applied to all the auxiliary anodes of the second row. The vertical control consists in closing the switch V for feeding the various cathodes of the same column through the common resistance R C. Among these cathodes, the cathode of the tube L is fed. Gnly the tube L has its anode, its auxiliary anode and its cathode fed, and it fires. The point E has its potential varied and the transistor T becomes conductive. The alternating current can then flow from X to Y The feeding of the tube L produces a voltage drop across the resistance R C, and if a voltage Vs is applied to the auxiliary anode of another tube of the same column during the operation, this tube will then be incapable of firing, since the potential applied to the cathode of this other tube is notVn, but V minus the voltage drop across the common resistance R C. An automatic blocking therefore occurs and protects a tube in operation in a column. in other words, only one tube can operate at a time in one column. -t is also to be noted that if the voltage Vs is suppressed at the auxiliary anode, the tube L memorises its operation and continues to operate between the anode and the cathode. In order t stop the operation, it is necessary to open the switch V providing the cathode potential.

The circuit arrangement illustrated in FIGURE 3 is an application to a matrix of the arrangement illustrated in FEGURE 1. It would similarly have been possible to illustrate a matrix arrangement whose basic circuit is that of FIGURE 2 Modifications of the device according to the invention can readily be made by the use of transistors on npn-type,

with which it is sufiicient to vary the polarities accordin ly. These modifications obviously fall within the scope of this invention. a

We claim:

l. A transistor switching device in a gas tube coincidence matrix selector, comprising a transistor interconnecting two lines of a matrix, said transistor having acontrol electrode for selectively blocking and unbloclcing said transistor depending on the potential of said control electrode, a resistance connected at one end to said control electrode, a multielcctrode gas tube including at least an anode, a cathode and an auxiliary anode, and having said anode connected to the other end or said resistance, means including a second resistance connected to said anode of said gas tube for applying a control voltage to block said transistor and simultaneously acting as supply voltage for said anode of the gas tube, and means for firing said gas tube to change the potential of said control electrode and thereby unblock said transistor, said lastmentioned means comprising two switches and means operative-1y connecting said switches to jointly control the firing of said gas tube.

2. A switching device according to claim 1 including means for connecting the auniliary'anode of the gas tube to a direct current source through a resistance and one of said switches and means for connecting the cathode of the gas tubeto another direct current source through resistance and the other of said switches, the firing of said tube being eilected by closing the two switches.

3. A switching device according to claim 1, wherein said means for firing said gas tube includes two identical circuits connected to the auxiliary anode of the gas tube, each of said identical circuits including a resistance connected by one of said switches to a direct current source and including a further resistance connected from a point intermediate the aforementioned resistance and switch of- 7 said circuit to the opposite pole of said last-mentioned direct current source, said tube being capable of firing only if the switches of each of said two identical circuits are closed.

4. A switching device according to claim 3 including means for connecting the cathode of the gas tube on the one hand through a resistance to a direct'current source and on the other hand through a condenser and a further switch means adapted to be connected to ground, the closing of said last-mentioned switch means during operation of the gas tube producing extinction of the tube.

5. A switching device according to claim 1, wherein said transistor includes emitter collector electrodes connected to said lines, respectively.

6. A selecting matrix employing a plurality of switching devices according to claim 5, comprising circuits disposed in horizontal lines and circuits disposed in vertical lines crossing the horizontal lines'and providing'for establishment of a connection between any horizontal line and vertical line, onesuch switching device being disposed at each crossing point of the horizontal line and of a vertical line, the emitter and collector of the transistor of each said device each being connected to a separate line of the respective crossed lines, means for energizing the anode of each gas tube through said second resistance by a voltage source common to the anodes of the tubes of each vertical line, means for energizing the auxiliary anode of each tube through at least one other resistance, the last-mentioned resistances of the auxiliary anodes of the tubes of a common horizontal line being connected to a common point which is in turn connected by control switch means for the application of a control voltage, each vertical line comprising means including a control circuit for applying a second voltage to the cathode of each of the gas tubes of the respective vertical line, the connection between a horizontal line and a vertical line being established by the operation of both the respective first mentioned control switch means of the horizontal line and the respective second-mentioned control circuit of the vertical line, these two operations producing the firing of the tube situated at the crossing point of the two lines and the operation of the tube being maintained as long as the respective gas tube remains conductive, while no other tube of the same vertical line can come into operation as long as the tube in operation itself remains operative.

7. A selecting matrix employing a plurality of switching devices according to claim 5, comprising circuits disposed in horizontal lines and circuits disposed in vertical lines crossing the horizontal line and providing for establishment of a connection between any horizontal line and any vertical line, one such switching device being disposed at each crossing point of a horizontal line and of a vertical line, the emitter and the collector of the transistor of each said device each being connected to a separate line of the respective crossed lines, means for energizing the anode of each gas tube through said second resistance from a voltage source common to the anodes of the tubes of each vertical line, means for energizing the auxiliary anode of each tube through another resistance, said lastmentioned resistances of the auxiliary anodes of the tubes of each common horizontal line being connected to a common point which is in turn connected to a control switch for the application of a control voltage, each said last-mentioned control switch constituting one of the two switches of each device along the respective horizontal line, each vertical line comprising a resistance and a control switch in series therewith connected to each of the cathodes of the gas tubes of the respective vertical line for applying thereto a control voltage, each said last-mentioned control switch constituting the other of the two switches of each device along said respective vertical line, the connection between a horizontal line and a vertical line being established by the closing of both the respective first-mentioned control switch of the horizontal line and the respective second-mentioned control switch of the vertical line, these two operations producing the firing of the tube situated at the crossing point of the two lines and the operation of the tube being maintained as long as the last-mentioned switch remains closed, while no other tube of the same vertical line can come into operation as long as the tube in operation itself remains operative.

References Qited in the file of this patent UNITED STATES PATENTS 2,603,716 Law July 15, 1952 2,627,039 MacWilliams Ian. 27, 1953 2,809,394 Dickinson Oct. 8, 1957 2,853,629 Felker Sept. 23, 1958 2,914,747 Straube Nov. 24, 1959 2,954,508 Burstow Sept. 27, 1960 3,015,697 Klinkhamer Ian. 2, 1962

Claims

1. A TRANSISTOR SWITCHING DEVICE IN A GAS TUBE COINCIDENCE MATRIX SELECTOR, COMPRISING A TRANSISTOR INTERCONNECTING TWO LINES OF A MATRIX, SAID TRANSISTOR HAVING A CONTROL ELECTRODE FOR SELECTIVELY BLOCKING AND UNBLOCKING SAID TRANSISTOR DEPENDING ON THE POTENTIAL OF SAID CONTROL ELECTRODE, A RESISTANCE CONNECTED AT ONE END TO SAID CONTROL ELECTRODE, A MULTI-ELECTRODE GAS TUBE INCLUDING AT LEAST AN ANODE, A CATHODE AND AN AUXILIARY ANODE, AND HAVING SAID ANODE CONNECTED TO THE OTHER END OF SAID RESISTANCE, MEANS INCLUDING A SECOND RESISTANCE CONNECTED TO SAID ANODE OF SAID GAS TUBE FOR APPLYING A CONTROL VOLTAGE TO BLOCK SAID TRANSISTOR AND SIMULTANEOUSLY ACTING AS SUPPLY VOLTAGE FOR SAID ANODE OF THE GAS TUBE, AND MEANS FOR FIRING SAID GAS TUBE TO CHANGE THE POTENTIAL OF SAID CONTROL ELECTRODE AND THEREBY UNBLOCK SAID TRANSISTOR, SAID LASTMENTIONED MEANS COMPRISING TWO SWITCHES AND MEANS OPERATIVELY CONNECTING SAID SWITCHES TO JOINTLY CONTROL THE FIRING OF SAID GAS TUBE.