US1606139A - Telephone system - Google Patents

Description

Nov. 9 1926.

E. L. BAULCH TELEPHONE SYSTEM Filed Oct. 9. 1924 2 Sheets-Sheet ll /nvenor [mes L. lBau/0") Q by my,

im. .9, 192s,l 1,606,139

- Y. l E. l.. BAULCH TELEPHONE SYSTEM Filed Oct. 9. 1924 A 2 `Sheets-Sheet 2 Patented Nov. 9, 1926.

, UNETE STATES PATE? ,GFFECE ERNEST L. BAULCH, QF MILLBURN, JERSEY, ASSIGNOR TO WESTERN ELECTRIC l COMPANY, INCORPORATED, 0F NEW YORK, Y., ACORPORA'IIONOF NEW YORK.

TELEPHONE SYSTEML Application led October 9, 1924. Serial No. 742,504.

nection desired. Calls intended for throughv connections are transferred to the through position and delayed inward calls are transferred to the outward position.

As to outgoing calls, it is customary for the operator at an A operators position at which such calls may originate, to make use of the service of a recording operator who is reached over a recording trunk and wao prepares a ticket bearing the number of the calling party and the number of the wanted party who may be reached over a long distance connection. The recording operator transmits the ticket to an 'outward toll operator who then selects a toll line leading in the proper direction, 'and when the operator at the distant end extends the call to the wanted subscriber, this outward operator in turn extends the connection to the calling subscriber through a B operators lposition as is well known in the art.

It is an object of this invention to simplify the extension of outgoing calls over toll lines in systems of the above type for certain kinds of traffic, for example, where the calling subscribers are located in the-y same exchange and the wanted subscribers may be reached over comparatively short lines1 that is, in cases where a large proportion of the calls from the originating ex-v change are for subscribers in nearby towns or suburbs. It has been found that it is not always practical, in particular for small exchanges, to have their recording operators attend to such short haul traflic. This is due principally to the fact that the cost of such service often exceeds the collectible revenue.

Another object is the provision of a simpliied traliic system of this type that is so designed as to give the maximum flexibility and means forcontinued growth with the least possible equipment of the more costly kind such as recording operators position and ticket distributing equipments.

To attain thesev objects in accordance with onefeature of the invention, there is provided at certain A operators positions multiple jack extensions for short toll lines by means of .which the A operators may extend connections over such toll lines directly ,from local subscribers without the assistance of either a recording operator, an outward operator or a B operator. In some instances it may bel advisable to have these multiplejacks at the A operators positions marked or otherwise identified by the name of the towns or suburbs to which the associated toll lines extend or else provide the A operators with written instructions ts to the terminating points of such toll mes.

Another feature of theinvention relates to the provision of means whereby a. connection established by an operator over a toll line cannot be interfered with by another op erator even though such otheroperator may disregard the usual busy signal provided for this purpose and attempt to establish a connection by inserting her plug into the jack of the engaged toll line.

Another feature relates to the provision of means for facilitating the transmission of supervisory signals between the operator at a distant end of the toll line and A operators'connected at the multiple jacks of such toll line. t

Another feature relates to the arrangement of these multiple jacks in the circuits of the toll lines in `such a manner that the ordinary incoming, through or outward toll operators jacks are normally connected directly to the toll lines while the multiple jacks are connected only on the insertion of the A operators plugs in such jacks. This arrangement is of advantage in that the circuits for the regular toll line service are normally maintained intact with Vthe least possible intermediate or encumbering switching devices involved.

'The invention may be more fully understood by referring to the accompanying drawings, in which Fig. l represents a pre ferred form of toll line provided with regular t^ line jacks and a multiple jack llU equipped in accordance with this invention. Fig. 2 represents a modified forni of toll line provided with equipment for performing supervisory functions between the operator at the distant end and the local operator.v Fig. 3 shows, in schematic form, a typical layout of the ordinary. toll line traffic system and the applicants invention as applied to such a system.

Referring now especially to Fig. 3?, the arrangement of the' invention as applied to an ordinary tolll traffic system will be described. ln' lthe case of incoming calls, the inward toll operator at position lmay receive the call by inserting plug 2 in pick 3 of toll line 4 and after ascertaining the number of the wanted subscribers line, she inserts plug 5 into jack 6 of a switching trunk 7 leading to aB operators position 22A and transmits the information to this operator who answers the call by inserting plug 8 intov jack 9l of the switching trunk 7. The B operator now proceeds to extend the connection to the wanted subscriber by inserting'her plug 10 into `iack 11 and complete the call to the wanted subscriber 12 in the usual manner. Y If the incoming call is intended for a subscriber located 4at a distant exchange, the inward operator transfers the call to the through operatorat position 13 and this operator by inserting plug 14e into jack, 15 and plug 16 into jack 17 extends the c'all to the outward trunk 18 leading to a distant exchange; or, if as is the case indelayed or similar types of calls, the inward operator decides to have the outward operator at position 2Oy attend to the incoming call, the connection is transferred to liack 19 and this operator will thus be notified that her assistanceis required.`

On the other hand, if an outward connection is desired, the outward operator at position 20, the recording operator at position 21 and the B operator at 22 are ordinarily involved in the following manner. In this case, a lo-cal subscriber, such as the one located at 25, will connect with an A operator at position 26, who after having` answered the call by inserting plug 27 in jack 28, ascertains the number of 'the wanted subscriber at a distant exchange and proceeds to insert plug 29 into jack 30 of a switching trunk 31 leading to a recording operators position 21. This operator answers by inserting plug 33 in jack 34 and now receives not only the wanted subscribers number but also the calling subscribers number from thev A operator, prepares a vticket containing` these numbers and transmits the vsaine through a ticket distributing system,

well known in the art to the outward operato'r at position 20. This outward operator then Vproceeds to secure a connection to the distant exchange over a toll line such as 4 kof h andling by the use of an order wire well known in the art. Villien the toll line has been assigned, she inserts plug 35 into jack 19 and completes, by the aid of the operator at the distant exchange, a connection to the wanted subscriber. When the wanted subscriber has been reached, the outward operator inserts plug 37 in jack 38 `of switching trunk 39 leading to the B operator at position 22 who in turn extends the connection to the calling subscriber 25 and thus the connection with the subscriber at 25 and the wanted subscriber the distant exchange is completed independent of the A operator at position 26' and the recording operator at position 21, which operators are therefore not further concerned with this connection.

lt should be noted that this procedure of completing toll connection is rather elaborate and time consuming and when the wanted subscriber may be reached through toll lines leading to nearby towns, the revenue collectible for such connections is comparatively7 small and in vmany instances is not commensurate with the cost of the service rendered in extending the connections. rllherefore, in accordance with this invention, a number of short toll linesv such as el, lea dingv to surrounding towns to which the traffic is particularly heavy may be equipped with appropriate, circuits and multiple jacks at A operators positions. By such an arrangement, local subscribers desiring connections to nearby towns may secure such service without having to wait or to be recalled when a toll connection has been established and the cost of such toll service will therefore be considerably reduced.` lt would, of course, not be practical to provide such service in all exchanges but rather in exchanges in such cities or towns where the regular long distance traffic is all that can ordinarily be handled by the existing recording operators equipment and whe/re such traffic may ten'iporarily increase as, for example, would beY the case in cities located near seaside resorts or summer colonies to which the toll service would be particularly heavy during the openseasons. In suoli cities the toll lines leading to these surrounding towns or colonies would be equipped with jacks at A operators switchboards and preferably marked with ythe name of such places or otherwise identified by the operator so that when outward calls are received for suoli towns or colonies from a local subscriber such as 25, the A operator at' 26 may, instead of passing` the call to the recording operator at position 2l, select a jack associated directly with a toll line leading to such town, for example` jack 40, and thus expedite the service and reduce the cost short haul traiiic.

Referring now particularly to Fig. l

which shows an embodiment of the invention as applied to toll line 4, it should be noted that a complete disclosure of the cir cuits associated with this toll line is shown, that is, for the extension of calls to ythe inward operator through jack 3 for throughv service through jack 15, outward service through jack 19 and outward service from the A operators position through jack 40. A detailed description of the functions taking place in this circuit during thev extension of these various types of calls will now be made beginning with the reception of a call through the incoming jack 3. In this case, the incoming call over toll line 4f causes the operation of the alternatingv current responsive relay 50 which closesa circuit for relay 52 as follows: battery, make before-break contact of relay 53, winding of relay 52, armature and front contact of A relay 50 to ground. The operation of relay 52 closes an obvious circuit for relay 54 at its armature and front contact Aand relay 54, in operating, closes a locking circuit for itself through its left-hand armature and front contact to battery at the make-before-break contact of relay 53. The operation of relay 54 also closes a circuit for busy signals 57 and 58 located respectively at the through and outward operators positions. This circuit may be traced from battery, right-hand armature and front contact of relay 54, winding of busy signals 57 and 58 in series toy ground. The operation of relay 54 also closes a circuit for relay as follows: battery, right-hand armature and front contact of relay 54, inner upper armature and back contact of relay 56, winding of relay 55 to ground. The operation of relay 55, closes'at its upper outer armature and front contact an obvious circuit fo-r busy signal 70 associated with multiple jack 40, and closes also at its lower armature and front contact a circuit from battery for the sleeve lead of the multiplejack 40 so as to provide a busy test potential Von this 1 jack for the A operator i-n case she should disregard the busy signal 70 and attempt to establish a connection to this engaged toll line by inserting her plug 29 in jack 40. It should also be noted that relay 55, in operating, closes at its inner upper armature and front contact a series contact for an all busy signal circuit such as is commonly used in circuits of this type. The lamp 59 at the inward operators position 1 is also illuminated the moment relay 54 operated over a circuit as follows: battery, make-beforebreak contacts of relay 53, left-handV armature and front contact of relay 54, righthand armature and back contact of relay 60, right-handV armature and back contact of relay 6l, signal 59 to ground. The inward operator is thus notified that her attention is required for an incoming call on this toll line.

In answering this call, the inward opera-` tor as hereinbefore stated, inserts plug 2 in jack 3, thus completing a circuit for relay l53 as follows: battery, sleeve contacts of plug 2 and jack 3, left-hand armature and back contact of relav 61, left hand armature and backl contactuof relay 60, wind.

ing of relay 53 to ground. The operation of relay 53 at its lefthand armature and back contact breaks the circuit for relay'50 which is normally bridged across the tip and ring leads of toll line 4. This latter relay which may or may not be operated depending on the presence or absence of ringing current on the toll line, will by therelease of its armature open the original energizing circuit for relay 52 which in releasing opens the original `energizing circuit for relay 54, so that relay 53 by operating and in opening the 'locking circuit for relay 54 at its make-before-b-reak contacts now permits relay 54 to release and extinguish signal 59. It should be noted, however, that the operation of relay 53 provides obvious substitute circuits for maintaining busy signals 57 and 58 and relay 55 operated. It is also clear that the battery supplied at the sleeve of ack .3 will now furnish a busy potential for the sleeves of jacks 15 and y19. lThe busy conditions established at the through, outward and A operators positions are therefore maintained and controlled by relay 53 until plug.2 is removed lfrom jack 3 at the end of the conversation when it releases and returns the toll line circuit to normal.

' ln case the incoming call on this toll line is intended for a through connection, thel inward operator receiving this information transfers the call to the through operators position at .13 by operating key 62. The operation of key 62 operates relays 54 and 60 over a circuit as follows: battery, right-hand winding of relay 54,`righthand armature and back contact of'r'elay 63, left-hand winding of relay to ground at key 62. The operation of relay 60 breaks the energizing circuit for relay 53 from the sleeve of jack 3, restoring this relay. to normal, while relay 54 in operating maintains at its right-hand armature and front contact the circuit for busy signals 57 and 58and through the maintenance of relay 55 energized by this same circuit the busy signal 7 0 is also maintained operated in a manner that is considered obvious in view of the previous description. lt should be noted that lamp 6.4 associated with the through operators position 13 will now be lighted over a circuit from' battery at the make-before-break Contact of relay 53, leftl hand armature and front contact of relay 54, right-hand armature and front contact of relay 60, right-hand winding of relay lul) lll]

lll

60 through lamp 64 to ground while lamp 59 is extinguished by the operator of the right-hand armature of relay 60. Relay 60 is now maintained operated through the circuit from battery at relay 53. The operator at the throughy position 13 now insertsher plug 1A in jack 15 and extends the call through to the distant exchange, as hereinbefore stated, over a toll line such as 18. The insertion of plug 1l in j ack 15 now operates relay 53 causing` relays 54e and 60 to be released and signal 64 to be extinguished. It should be noted that should the inward operator neglect to release key 62 signal 64 is nevertheless extinguished even though relays 54- and 60 may thereby remain operated.

Should the operator find that the incoming call requires the attention of the outward voperator at 20 she manipulates key 65 and operations similar to those described for a through connection take place except that relay 61 is operated in place of relay 60 and the. outward operators lamp 66 is lighted in place of lamp 64. In attending to outgoing calls over the toll line 4t, under these circumstances the operator at 20 may,vby inserting` plug 35 in jack 19, close a connection for the tip and ring leads over the toll line as is the usual practice and also establish a sleeve circuit as follows: battery on the sleeve contact of plug 35 of a cord circuit similar to that shown at the right of jack 19, sleeve contact of this jack 19winding of relay 53 to ground. The operation of relay 53 causes the release of relays 5ft and61 but busy signals 57, 58 and 70 are maintained as hereinbefore described operated from' battery at the front contact of relay and lamp 66 is extinguished.

In cases where the outward operator originates an outgoing call, that is, without the intervention of the inward operator the procedure is the same except that the insertion of plug 35 in jack 19 will merely operate relay 53 and thereby cause the operation of busy signals 57 and 58 directly and busy signal indirectly by the operation of relay 55 and also establish a busy potential on the sleeve of jacks 3, 15 and 40 as hereinbefore described.

If an outgoing toll call can be attended to by the A operator without the aid of intermediate `operators by extending the connection directly from her position through a multiple jack l0 she inserts plug 29 in this jack and a connection is then established as follows: first, sleeve circuit may be traced from battery, lamp 79, sleeve contacts of plug 29 and jack 40, lower armature and ack contact of relay 55, winding of relay 63 to ground. rllhe operation of relay 63 closes a circuit for relay 72 and another circuit for relay 56 from battery through the respective windings of these relays to ground through `the left hand armaturel and front Contact of relay 63. The operation of relay 72 disconnects the tip and ring leads of the inward, through and outward jacks 3, 15 and 19, respectively, which are normally associated with the toll line 4- and completes the talking leads fromthe j ack 40 at the A operators position to this outgoing end. Relay 72 also closes at its outer lower armature a series connection for the all busy circuit hereinbefore mentioned. The operation of relay 56 closes an obvious circuit for the busy signal 70 at its lower armature and front contact and at its upper outer armature and front contact closes an operating circuit for relay 53 and at the same time provides a busy potential at the sleeves of the inward, through and outward jacks. Relay 56 also opens a circuit 'for relay 55 so thatV when relay 53 operates this relay cannot become energized which is obviously not necessary in this type of connection. TheV operation of relay 53 closes a circuit for the busy signals 57' and 58 as hereinbefore described and opens at its left hand armature and back contact the circuit for relay 50.y This is to prevent the operation of relays 50, 52 and 54;

in this type of connection when ringing cury rent is applied which may be done by the operation of the usual ringing key 8O in thel A operators cord circuit.

rThe inductance in parallel with jack 40 is provided to put a` shunt across the tip and ring of the A operators cord to extinguish supervisory lamp 7 9 so that the operator will not inadvertently take down the connection during a conversation. In Fig. 2 an inductance of a similar nature is closed across the tip and ring of jack 10 through the contacts of a relay, whereby a more elaborate supervision is provided, as will be explained hereinafter.

ln the modified form of the toll line shown in Fig. 2, the results obtained will be the same as with the circuit shown in Fig. 1 and described above. It is identical with the preferred form of the invention, only such changes being made as are necessary for the inclusion of the special supervisory features mentioned above.` As far as practical, the same referenceV numerals have been applied to corresponding parts in the two circuits.

Incoming calls rreceived over this circuit causes relays 50 and 54 to operate in succession. Relay 54 being locked up from the battery at the make-before-break contact of relay 53 causes the lighting of lamp 59. The busy signals 57, 58 and 70 are operated through circuits established at the inner left armature and front contact of relay 54 which also establishesa busy potential on the sleeve of multiple jack 40. Vhen the inward operator answers this call, relay 53 operates and causes the same fuI1ctions to take place as in the preferred form when relay 53 operates. Through and outward callsat jacks l5 and 19 also affect the circuit ,in the same manner as described in connection with F ig. l and as the circuits in relation to these operations are easily traced, no further description will be made in this respect.

In 4extending toll connections directly from the A operators position, the operation of the circuits is also similar to that `described in Fig. 1that is, relay 63 operates when plug 29 is inserted in jack 40y and the operation of this relay causes the operation of relays and 72. Relay 72 as stated, extends the tip and ring from jack to the toll line 4 and relay 56 establislies the desired busy conditions. Relay 56 also completes a portion of a circuit for transmitted to the other end of the toll line- 4 where it will operate relay 50 which thereupon closes an obvious circuit for relay 7 6 through the inner lower armature and front contact of relay 56. Upon `the operation of relay 76 a shunt across the tip and ring of the A operators cord is opened sov that the supervisory lamp 7 9 becomes illuminat- Thus one A operator may signal' another. As soon as lrey 8O is released relays and 76 are released and the bridge across the tip and ring of the cord circuit is closed causing the operation of relay 78 to extinguish lamp 79 asis well known in the art.

If the operator at the distant end decides to call the A operator for the further supervision of the established connection,

y ringing current is supplied to the toll line 4 from thel distant end as is Well known in the art, causing the operation of relay 50. As the ringing key of the operators cord circuit is now released, the operation of relay 50 and the consequent operation of relay 76 and opening of the bridge acrossthe tip and ring of the local jack, causes the release of relay v78 and the lighting-of lamp 79. Condensers 82 and 83 are inserted in the tip and ring leads and the'circuit in order that relay 50 may operate on the incoming ringing current.

Condenser 84 is inserted in series with rebattery and ground'supplied from the A operators coi'd when plug 29 is connected to jack 40. i What is claimed is:

l. In' a telephone system, a transmission line terminating in two groups of jacks each f at. a plurality of positions in a central office, one group normally connected and the other normally disconnected from said line, means vresponsive to a connection established through the jacks of either group fory rendering attempted.. connections through the jacks of the other group ineffective, a busy signal at several of said positions, a Acall signal at one of saidpositions and a ringing responsive means for operating thecalll signal, for operating the busy signals and for establishing a busy condition on the sleeve of the jack at certain of said positions, means for maintaining said call signal and busy signal operated and the established busy condition effective after the cessation of the ringing, and means responsive to the answering of the call at the position where the call signal is located for releasing said call signal, for maintaining the busy signal operated, for maintaining the established busy conditions effective and for establishing a busycondition on the sleeve of the jacks at the remaining positions.

2. In a telephone system, a transmission line terminating in two groups of acks each at a plurality of positions in a central` oftice, one group normally connected and the other normally disconnected from said line, means responsive to a connection established through the jacks of either group for renderingk attempted connections through the jacks of the other group ineffective, a busy signal at certain of said positions, a call signal at certain of said positions, a ringing responsive means for operating the call signal at one of the positions, for operating all of said busy signals and for establishing a busy condition on the sleeves of the jacks at certain of said positions, means for maintaining said call signal and the busy signals operated and the established busy conditions effective after ringing has ceased, means for releasing the operated call signal and operating any oneof the other call signals, means responsive in answering the call at the position where the associated call signal is operated for releasing said call signal, fortransferring the control over the busy signals and the established busy conditions to said last mentioned means, for maintaining said busy signals operated and the busy conditions effective and for establishing busy conditions on the sleeve of the l jacks at the remaining positions.

3. In a telephone system, a transmission line terminating in two groups of jacks each at a plurality of positions in a central of- 1 lice, one group normally connected and the other normally disconnected `from said line, means for calling from any of the acks normally connected to the Itransmission line, rmeans for calling' Afrom any of the normally rdisconnected jacks operative to connect said jacks to the line and disconnect the jacks of the kother group from lthe line, and means responsive to a call from any jack for es- ;tablishing busy indications at all of said positions. p

4. In a telephone system, a transmission line terminating in two groups of jacks each :at a `plurality of positions ina central ofice, busy signals at all of the jacks of one group' and at all but oneof the jacks of the other group, means for operating said busy ,signals and for establishing' a busy condition at the jack at which no busy signal is located operative When a connection is ,made througha Jack of either group, and means i'or disabling the jacks of one group VWhen connection is made through a jack of the Y ERNEST L. BAULCH.

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