US2376346A - Telecommunication system - Google Patents

Description

4 Sheets-Sheet 1 G. DEAKIN TELECOMMUNICATION- SYSTEM Filed June 2l, 1943 L S man May 22, 1945.

May 22, 1945. G. DEAKIN y 2,376,346

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G. DEAKIN TELECOMMUNICATION SYSTEM Filed June 21, 1945 May 22, 1945.

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TRUNK FINDERS n A CORD' CT.. OUT TRUNK JACK G. DEAKIN 2,376,346

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f r fr n: 6 4g 0 0 a l e S 1 s t *1L *L *L *L *L El R Patented May 2,2, 1945 2,316,346 'rEmcoMMUNIoA'rroN SYSTEM Gerald Deakin, ternational New York, N. Y.,

New York, N. Y., Standard Electric Corporation,

a corporation ot Delaware assignor to In- Appllcation June 21, 1943, Serial No. 491,628

Claims.

This invention relates to new and useful improvements in selecting arrangements for telecommunication systems and particularly to arrangements adapted for controlling successive `se lectlng stages in automatic telephone exchange systems.

According to the present invention, a selecting arrangement is provided in which a broad band or potentials is provided to determine a first selecting stage. This broad band includes a plurality of narrow bands of potentials determinative of a second selecting stage. A plurality of first finder switches, e. g., are arranged to operate on any of the narrow bands, i. e., on the full width of the broad band to perform the first-selection. Then second switches, e. g., a group of finders operate in accordance with the specific narrow band of potentials applied. For instance, the potentials selected by a first finder is extended to the banks of a plurality of second finders, each of which is arranged to select only one tentials.

The selecting arrangement will flndmany applications to telecommunication systems. When applied to arrangements for identifying the designations of calling lines, a single identifying equipment provided in an exchange may be used simultaneously to identify a plurality of calling lines, as distinguished from prior selecting arrangements which permitted the identification of only one line at a time. l

The invention will now -be described in greater detail as applied to a telephone exchange system of the general type described in my co-pending application, Serial No. 484,184, filed April 23, 1943, and the application of H. F. Herbig, Serial No. 485,827, filed May 6, 1943, now Patent No. 2,354,682, issued August l, 1944.

In the drawings which illustrate only as much of the system as is necessary for a clear understanding ofthe invention 1 illustrates the general selecting scheme;

Fig. 2, the test circuit of one of the identification finders illustrated in Fig. 1;

Fig. 3, some uses of the identification arrange-l ment illustrated in Figs. 1 and 2; and

Fig. 4, the application of the identification arrangement to out-trunking.

Referring now to Fig. 1, only the test terminals and test brushes are shown of switches used in the establishment of an automatic telephone connection of the type `illustrated in my said co'- pending'application. A calling line may .beconnected with a called line over a first line finder. an A link, a second line finder, a B link and then over first, second, third, fourth, penultimate and iinal group selectors. However, in the present narrow band of p0- arrangement, no identification relay is provided in each A link, the t brush,oify each iirst line finder being connectedr direct to a terminal of a second 1, I have shown two groups arrangement andv line nnder. Each t wire of an A link in the same group of one hundred lines, is connected through a positively polarized rectifier S+ and a resistance R. to a common starting relay Gsr. In Fig.

of rst line finders, group #l serving lines |00 to |99 and group 4#t5 serving lines 500 to 599.

A plurality of groups of first identication finders is provided, each group having terminal banks which are multipled to the corresponding T terminals in the banks of the rst line iinders. One first identification iinder is provided per one hundred subscribers lines. These identification finders, just as the line finders and group selectors have, of course, the other customary terminals and cooperating brushes.

The t brushes of the iirst identification finders are connected to the terminal banks of second identification finders per identification circuit. A test circuit like the brush of each second identification nder. The t wires of the six second identification finders are shown as connected to six different switching circuits. I'he first terminates at a wire chiefs desk on key IKI which is arranged to apply ground to the identification circuit and +48 volts to the T terminal of a first group Selector. TB #2 of the second identification finder is connected with a relay IRI forming-part of the #l toll trunk and adapted to apply ground to the identification circuit and +46 volts to the T terminal of a second4 group selector. 'I'he #3 test brush of the second identification finder is connected with the #2 toll trunk, the relay IR! oi which is arranged to apply ground to the identification circuit and +44 volts to a second GR. The #4 test brush of the second identificatiorrfinder is connected with a relay IRS of an automatic ticketing arrangement adapted to apply ground to the circuit and +42 ,volts to a second GR. The #5 test brush is connected with relay IRA, forming part of a special line service which is/ adapted to apply ground to the circuit and volts battery to a third GR. The #6 brush of the second identification finder is connected with a special portable test Set which may be used by switchmen to determine the number of a calling subscriber or trunk.- The key 1K2 in the special test set is adapted to apply ground to the circuit. and +50 volts to any test terminal in the system.

Whenever any one of these keys IKI or IKZ or relays IRI-4 is operated, positive battery of 40 to 50 volts is applied to the test conductors of the connection that has been built up fromthe calling line through the exchange to the respective position. Through a positively polarized rectifier S+ and a resistance R, this potential is applied to a common starting relay Gsr.

Assuming, for instance, that line 598 has been of which there is onel extended through a first line finder, a second line finder and a rst group selector, to the wire chiefs position, when the key IKI is actuated, +48 volts will be connected through the t wires of the first group selector and the second line finder and then through S+3, R3 and GSR2 to ground Similarly, the test set may be connected to the test wire of a final selector and when key 1K2 is operated, +50 volts is applied through this key and then through the penultimate, fourth, third, second and first group selectors, the second line finder, S+I, RI and GSRI to ground.

When GSRZ operates, it closes an energizing circuit from ground over its armature and front contact and the winding of power magnet PIS and the left hand back contact and armature o relay TRS to grounded battery. The power magnet'PIS will control the movement of the brushes of the #5 first identification finder to hunt for the t wire of the calling line, the terminals of this switch being multipled to the test wires of lines Nos. 500-599 and thus to the test terminals of the first line finders serving this group of lines. When the calling line is found, a circuit is closed from ground over the winding of relay TRS, the left hand back contact and armature of relay ARS, TBS, the terminal in the first identification finder and in the first line finder of line No. 599 and the brush of the operated first line finder to the +48 volt battery connected thereto by the second LF from the wire chiefs key IKI. Relay TRS opens the circuit of magnet PIS and thus stops the first identification finder brushes. Over its right hand armature and front Contact, this relay closes an energizing circuit for the relay ARS which locks up to the ground applied by relay GSR2. Through its front contact, the relay ARS connects TBS of the first identification finder to its assigned terminal in the banks of the second identification finders, in the present case t2.

If the second toll trunk were selected by a line, e. g. #500, then upon the operation of the toll identification relay IR2, GSR2 would be operated from +44 volts over S(+) I and RI. Should this happen after the key IKI is operated, then the circuit of the clutch magnet PIS will be opened by TRS when brush TBS reaches the first T terminal to which battery is applied. Since there is only one first identification finder per hundred lines, no double connection can take place. The toll call on line 50D must wait for the identification of the line S99, which will happen in two to four seconds. Should the key IKI and relay IRI of the first toll trunk be operated simultaneously, then both relays GSR! and GSRZ will be operated and will cause their associated first identication finders to hunt simultaneously.

' Each of. these will select the calling T terminal in its bank. The #l second identification finder will then pick up the first identification finder to which +48 volts was connected by key IKI and the #2 second identification finder will pick up the first identification finder to which +48 volts was applied by relay IRI. This is so because as will presently be described, each second identification finder can stop only on a predetermined potential applied to its terminals.

Fig. 2 shows a typical control circuit for the second identification finders. All these circuits are alike except that as indicated in Fig. 1, they are connected tothe ground contacts of a difierent key IK or a different relay IR. The only difference between the various circuits is that in each the battery marked -l-N volts has a different voltage. The voltage of this battery is given in the dotted square appearing adjacent to the second identification finder brushes in Fig. l and corresponds to the voltage that is applied by the identification key or the identification relay to the connection. This voltage is permanently connected over a resistance R to the cathode of a three electrode vacuum tube VI and to the grid of a similar tube V2.

When the test brush TB of the second identification finder contacts with the terminal to which the test brush of the first identification finder vand the relay AR associated therewith has extended the calling test circuit, then the test potential applied 'to this circuit, e. g. +48 volts, Will be connected over the test brush of the second identification finder to the control grid of the first tube VI and the cathode of the second tube V2.

In the present case, upon the actuation of IKI a circuit is closed from ground through the'lower contact `of the key IKI, .the outer armature and back contact of relay BR and the winding of relay AR of the second I. F. to grounded battery. The relay AR becomes energized and closes an energizing circuit from grounded battery over power magnet P of the second identification finder, the back contact and armature of relay GVR, the right hand armature and front contact of relay AR, the outer armature and back contact of relay BR to ground at the key IKI.` The power magnet controls the movementof the brushes of the second identification finder #l until the test brush thereofAY encounters, as above stated, the test terminal to which the key IKI had applied +48 volts battery over the #5 first -I. F. When in the control circuit of the #l second identification finder the same potential is applied to the cathodes and the grids of both tubes, and only then, a gas valve GV will be `-operated. 'While different potentials are` applied to Vl and V2 the control electrode CE of GV will be kept below ionizing potential. However, when the same voltages are applied to the two tubes, then they will not draw appreciable current and the full potential of the battery HTB will cause GV to strike, whereupon relay GVR connected tothe anode A will become energized. Thiswill open Vthe circuit of the magnet P and stop the second identification finder brushes on theselected terminals. The ground from key IKI is now extended by the armature of relay GVR to the winding of relay BR which first locks up to the ground at the key IKI and then breaks the circuit of relay AR. The gas valve GV is extinguished and the relay GVR becomes de-energized. The power magnet P cannot again become energized. The relay BR remains locked up until the identification key ory identification relay is released.

Fig. 3 illustrates other applications of the invention to telephone selecting systems. Here again only the t wires are shown, the balance of the switching system being assumed to be of the type disclosed in my said co-pending application. In this arrangement, first and second line finders, first group selectors, special service second group selectors and toll third group selectors, are illustrated. The toll third group selectors have access to a CLR toll board and a certain number of different groups of automatic ticketing positions and out-toll trunks.

A common starting relay GSR3 is connected in parallel to the t wires of the A links and a common starting relay GSR4 is connected in parallel to the t wires of the toll third group selectors.

`ates the identication key,

, GSR3 and GSR4. As in Assuming, for instance, that a calling subscriber dials a number which will cause the automatic switches to operate to connect his line with the CLR board, when the operator at this board actushe will apply +46 volts to the t wire causing, as above stated, the energizing of both relays GSR3 and GSR4. The rst identication lnder will then be operated as explained in connection with Fig. l to pick up the t wire whereupon the second identification finder, which is set for +46 volts, will pick up the rst identification finder and cause the display- .ing of the number of the calling line on the number` indicator provided at the position of the CLR operator. i

GSRA plays no role in this connection since none of the auxiliary nders is assumed to be set to operate on the application of +46 volts.

Should the CLR operator desire to introduce a repeater into the connection, she will depress her repeater key causing the application of +54 volts to the t wire. This again will operate both relays the rst case GSR3 will cause the first identification finder to pick up the t wire but since none of the second identication nders is assumed to be set to operate on +54 volts, no second identification finder will select the first identification 'finden i, However, relay GSRd will cause some or all the auxiliary nders to hunt for the calling t wires in the same man-y ner as GSR3 did for the rst I. F. The auxiliary finder marked Repeater is set for +54 volts (see Fig. 2) and its T brush will hunt until it encounters the 1: wire leading to the toll third group selector to which +54 volts was applied by the operator.

Obviously, each auxiliary nder has the required number of brushes and other means for controlling4 all the necessary switching operations. the toll third group selector which operates when the auxiliary-finder picks up this group selector to'open the t wire towards the first line iinder. This will leave the t wire free from the repeater to the toll operator for such subsequent use as may be necessary for the control of the repeater, e. g., to adjust the gain of the amplier.

i Obviously, an allotter may be provided to assign the auxiliary circuits, one at a time, to hunt for the call.'

Should the CLR operator wish to transfer the call to another operator, e. g.,at the A toll board, she may press her transfer key and apply +56 volts to the t wire. This will cause an auxiliary nder to extend the call to the A toll position.

The CLR operator may actuate the meter relay MR of the calling party as many times as she wishes by depressing a metering key MMK which applies -48 volts to the t wire. Since the meter relay is connected with the t wire over a negatively polarized rectier, only it and not the relays GSR3 and GSR4 will be operated.

Assuming that the calling subscriber dials the number of a called subscriber associated with a distant exchange, and further assuming that +52 volts is applied to the t wire of the automatic out-trunk, the auxiliary nder marked automatic ticketer will connect with a toll third group selector. When this happens, it will operate the relay PR connected with this group selector which The drawings merely show a relay PR in' opens the t wire towards the out-trunk. At the same \time the automatic ticketer, by suitable means such as a relay, applies +42 volts to the t wire towards the calling line. Not onlythe rst but also the second identification nder which is set to.operate on +42 volts, will now operate,V

after which the number of the calling party is transmitted to the automatic ticketer in the same manner as described in connection with the ,CLR position.

Assuming in the last case that a repeater was automatically introduced upon the Vselection of the out-trunk by applying +54 volts to the t wire after having rst applied +52 volts, as. above described, a repeater will be automatically connected with the circuit.

Fig. 4 illustrates how this invention is applied for controlling straightforward trunking from a manual board. Each operator or group of operators has as many out-trunk jacks as are required for simultaneous out-trunk connections. In the drawings, six out-trunk groups, each group having a common trunk finder bank multiple are shown. A special potential is assigned to each trunk. The band extends from +40 volts to +50 volts.y Each toll operator has a set of keys by means of which corresponding potentials may be applied to the t wire or sleeve of the cord. For instance, key Kl applies +50 volts, key K2, +48 volts, etc., key K6, +40 volts.

When the operator depresses the proper key and inserts the plug of her cord circuit into a free out-trunk jack individual to her position or an adjacent position, then a common starting relay GSR5 is energized over resistance R, back contact and armature of relay ARS, the sleeve wire of the jack and plug, armature and back contact of relay CR, the positively polarized rectier S+,- and say, key K3 to +46 Volts. The relay GSR5 closes an energizing circuit, from grounded battery over its armature and front contact and the power magnets P of all the idle trunk finders in the group to ground to hunt for 4the calling line. As indicated in Fig, 4, only the third group of trunk finders operates on +46 volts and therefore only this one can respond when the particular cord is reached to which +46 volts was connected, as has been explained in connection with Fig. 2. When this happens, relay ARS is energized, opens the circuit of relay GSR5, whereupon all the unsuccessfully hunting trunk finders will stop. ARE will apply negative battery over resistance R and its right hand front contact and armature to the sleeve of the jack and plug, whereby relay CR, which is grounded over a negatively polarized rectier S becomes energized and disconnects the keyset which may now be used with another cord circuit.

Obviously, the invention is applicabile to many other selective or trunking schemes.

Whatl is claimed is:

1. In combination, a rst and a second switching device, a source of potentials, means for applying pairs of different potentials to said devices, eachpar of potentials representing a different switching operation, means operative upon the application of any pair of potentials for acof selectively operable devices, a source of potentials, means for applying a plurality of?, pairs oi' I operative upon the application of any potential for actuating the ilrst group of devices to perform the rst step of the selecting operation designated by the potential applied thereto, and means for operating the second group device to which the other potential of the pair has been applied to perform the second step of the selecting operation.

3. In combination, a first and a second group of selectively operable devices, a plurality of lines, a source of potentials, means for applying a plurality oi' diierent pairs of identical potentials, one to said lines and the other to the second group of devices, means operative thereupon for actuating the first groupof devices to select the line to which the potential has been applied, and means for operating the second group device to which the same potential has been applied as to the line to select the operated iirst device.

4. In combination, a ilrst and a second group of selectively operable devices, a plurality of lines, a source of potentials, means for applying a plurality of dierent potentials to said lines and second group of devices, means operative thereupon for actuating the ilrst group of devices to connect with the line to which the potential has been applied, and means for operating the second group device to which the same potential has been applied as to the line to connect with said line over the operated iirst device. o

o. In combination, a iirst and a second group of selectively operable devices, each having a bank of terminals and a cooperating set of brushes, a plurality of lines connected in multiple to the terminal banks of the ilrst devices, a source of potentials, means for applying a plurality of different potentials to said of the second group of devices, means operative thereupon for actuating the first group of devices to connect with the terminal of the line to which the'potential has been applied, and means for operating the second group device to which the same potential has been applied as to the line to connect with said line over the brushes of the operated first device.

6. In combination, a first and a second group oiiselectively operable devices, a, plurality of lines, a source of D. C. potentials, means for applying potentials diiering in voltage between predetermined lower and upper limits to said lines and second group of devices, means operative thereupon for actuating the rst group of devices to connect with the line to which 'a potential has been applied. and means for operating the second group device to which potential of the same volt age has been applied as to the line to connect with said line over the operated first device.

7. In combination, a plurality of groups of rst selectively operable devices, a plurality of second selectively operable devices, a source of potentials, means for applying different potentials from lsaid source to one of the groups of first devices and to the second devices, each potential designatlng a different selecting operation, means operable upon the application of any potential to the iirst group for operating a rst device of said group to perform the operation designated by the lines and to the brushes' f lng group to engage the tipled to the lines of the corresponding group and a set of cooperating brushes, a plurality of second selectively operable devices, each having a set of brushes and a cooperating bank of terminals to which the brushes of all the the iirst devices are multipled, a source of potentials, means for applying different potentials from said source to said lines and to the brushes of the second devices, means operable upon the application of any potential to a' line of a group for operating the iirst devices of the corresponding group to operate the brushes for engaging the terminals of said line, and means operative thereupon for actuating the brushes of the second device to which the same potential has been applied as to the line to engage the terminals to which the brushes of the operated lrst device are multipled.

9. In combination, a plurality of groups of lines, a, plurality of groups of rst selectively operable devices,`one group for each group of lines,

each device having a, bank of terminals multipled to the lines of the corresponding group and a' set of cooperating brushes, a plurality of second selectively operable devices, each having a .set of brushes and a cooperating bank of terminals to which the brushes of all the rst devices are multipled, a source of D. C. potentials, means for applying a potential of diierent voltages from said source to said lines and a certain voltage to the brushes of each second device, means operable upon the application of any'voltage to a line of a group for operating the brushes of the rst devices of the corresponding group to engage the terminals of said line, and means operative thereupon for actuating the brushes of the second device to which the same voltage has been applied as to the line to engage the terminals to' operated first device which the brushes of the are multipled.

l0. In combination, a, plurality of` groups of lines, a plurality of groups of iirst selectively operable devices, one group for each group of lines, each device having a bank of terminals multipled to the lines of the corresponding group and a set of cooperating brushes, a plurality of second selectively operable devices, each having a set of brushes and a cooperating bank of terminals to which the brushes of all the first devices are multipled, a source of potentials, means for applying diiferent potentials from said source to said lines and to the brushes of the second devices, means operable upon the application of any potential to a line of a group for operating the brushes of the rst devices of the correspond- Aterminals of said line, and means operative thereupon for actuating the brushes of the second device to which the same potential has been applied as to the line to engage the terminals to which the brushes of the operated rst device are multipled.

GERALD DEAKIN.

-, CERTIFICATE oF CQRRECTION.

Patent No. 2,576,5Li6. may 22, 1915.

GERALD DEAKIN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page l, second column, line 21, before the word "brush" insert --one illustrated in Fig. 2, is associated with the t-f; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

signed and sealed this 6th dey of November, A. D. 19LL5.

Leslie Frazer (Seal) First Assistant Commissioner of Patents.

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