US2139798A - Telegraph switchboard switching system - Google Patents

Description

Dec. 13, 1938. A. R. BONORDEN ET AL 2,139,798

TELEGRAPH SWITCHBOARD SWITCHINGSYSTEM Filed Aug. 26, 1936 2 Sheets-Sheet 1 P051? F/GJ ARBONKORDEN Lam ; F. J. CARTER F. H. HA NLE r IN VE N 7DRS ,ATZORNEV Dec. 13, 1938. A. R. BONORDEN ET AL. 2,139,798

TELEGRAPH SWITCHBOARD SWITCHING SYSTEM 2 Sheets-Sheet 2 Filed Aug. 26 1936 ARBONORDEN lNl/ENTORS: 1-1.1. CARTER FJiH/INLEY ATTORNEY Patented Dec. 13, 1938 UNITED STATES TELEGRAPH SWITCHBOARD SWITCHING SYSTEM Allen R. Bonorden, Fanwood, Frank J. Carter, Millburn, and Frank H. Hanley, Butler, N. J., assignors to American Telephone and Telegraph Company, a corporation of New York Application August 26,

Claims.

This invention relates to telegraph systems and more particularly to supervising and maintaining private wire telegraph service over intercity telegraph trunk circuits between test board attendants located in different cities.

An object of the invention is to permit an attendant at a telegraph switchboard in one cality to be connected with any one of a plurality of attendants at a switchboard in a difierent 30 locality.

It is essential in test board operation in a telegraph system for the attendant in two lo calities, having charge of a particular service at their respective switchboards, to obtain direct communication with each other and consequently it is desirable to have an arrangement which will facilitate certain direct communication or permit of an incoming call being rapidly transferred to an attendant responsible for a particui0 lar service. In both toll and telephone practice the transfer of calls received over certain trunks or lines is possible to a very limited extent, that is, the facilities at present permit the transfer to one, or at the most, two points in the oflice.

, According to the present invention, the facilities permit each position in a line of test boards to become a potential transfer point and in the larger ofiices these facilities extend to arrange ments for transferring a call to any one of two or more positions. In other words, an attendant at a multi-position switchboard may upon receiving an incoming call over an intercity telegraph communication trunk, transfer the incoming call signal to any particular one of a plurality Q3 of trunk lamps, each of which is located at a different position in the switchboard.

A more complete understanding of the inven tion may be obtained from the followingdescription when read in connection with the accompanying drawings in which:

Figure 1 shows line circuit equipment of a multiposition switchboard or test board arranged according to this invention and provided with one primary answering position and a plurality of secondary answering positions.

Fig. 2 shows line circuit equipment of a multiposition switchboard or test board arranged according to this invention, with two primary answering positions and with provision for a plurality of secondary answering positions.

Referring to Fig. 1, at position 1 are terminated three inter-city telegraph communication trunks, mil, Elli, and H32, which may extend from another switchboard at some distant city, at which switchboard they may connect with apparatus similar to that of Fig. 1 and terminate respectively, at grounds H33, H35 and H05. Actually, these trunks terminate at terminating telegraph repeaters in the same ofiice, the line side 60 of each repeater extends to a like repeater in 1936, Serial No. 98,054

the distant city. However, for the purpose of reducing the disclosure of the invention to its simplest form the repeaters are omitted. Associated with the trunks are primary answering lamps E86, l0? and I08 and associated jacks I09, H0 and ill located at primary position 1; To enable the attendant at position 1 to respond to a lighted answering lamp a teletypewriter or manual telegraph, cord circuit, represented by the abbreviated circuit schematic enclosed in the box H2 is provided. Secondary answering positions 2, 3 and 4 are also shown, to each of which positions the attendant at position 1 may selectively transfer an incoming call, when such transfer is required by the operation of key H3, H4 or H5, which efiects the lighting of the secondary answering lamp at the called positions 2, 3 and respectively. The attendants at the secondary positions are also provided with teletypewriter, or manual telegraph, cord circuits H6, H1 and 1 l8.

A. detailed description of the operation of the arrangement of Fig. 1 will now be given. Let it be assumed that an attendant at a distant city desires to communicate over trunk N10 with an attendant at one of the positions of the switchboard, the circuits of which are shown by Fig. 1. To initiate the call, the distant attendant will cause, in some suitable manner, ground I93 to be momentarily disconnected from trunk MB. This may be done by momentarily operating the break key of a teletypewriter circuit, after plugging intothe line jack with a teletypewriter cord circuit, or some other suitable method of obtaining a momentary circuit opening may be used. Normally a circuit is closed from ground I83 over line conductor liiii, through lowermost contacts of primary answering jack Hi9, through winding of primary line relay H9, lower contacts of secondary answering jacks l20, l2l, I22 and of other similar jacks, not shown, the omission of which are indicated by broken lines, to the grounded battery 23. In response to this momentary opening the normally operated relay l H! releases, and closes a circuit from battery through the winding of relay i2 3, middle normally closed contacts of jack Hi9, upper normally closed contacts of jacksv I29, i2l, I22 and other jacks not shown, to ground 125. Relay i2 1 operates and locks to battery with its inner contacts, and with its outer contacts closes an obvious circuit through line lamp H36, which is lighted. When the circuit of trunk l Bil is closed again after its momentary opening, relay i It reoperates. In response to the lighted line lamp 306, the attendant of position 1 inserts the plug of teletypewriter cord circuit H2 into jack [09 operating the middle contact of jack I89 and opening the circuit through the winding of relay l 2 1, which releases, extinguishing lamp I96. Plugging into jack I09 also opens its lowermost contacts and effects the series insertion into trunk I of the teletypewriter cord circuit H2. Theattendant of position 1 is now in telegraphic communication with the distant attendant who initiated the call and is requested to transfer the call to some secondary position, position 3, for instance, and in order to effect this transfer operates momentarily transfer key H4, assigned for transfers to position 3. Transfer key I4 is held operated until lamp I33 lights as hereinafter described, causing thereby the operation of secondary line relay I26 in a circuit traced from battery through the left inner contacts of key H3, left outer contacts of key I I4, winding of relay I21, over vertical conductor I32, through uppermost operated contacts of jack I09, over conductor I28, through winding of relay I26, over conductor I29, through right operated outer contacts of key I I 4, to ground on the right inner contacts of key H3. Relay I26 in operating closes a circuit from battery through the winding of relay I30, upper contacts of jacks I2I, I22 and jacks, not shown, of succeeding positions to ground I25. Relay I30 operates and locks to battery with its inner contacts and with its outer contacts closes an obvious circuit to ground through secondary line lamp I3I, which lights. Simultaneously with relay I26, relay I2'I operates, and lights pilot lamp I33 through an obvious circuit, thereby indicating to the attendant of position 1 that the circuit through the winding of relay I26 has been satisfactorily closed, that now transfer key H4 may be released and plug of cord circuit H2 removed from jack I09, releasing thereby relay I 21 and extinguishing lamp I333. The attendant of position 3 now inserts into secondary answering jack I 2| the plug of positional teletypewriter cord circuit H'I, thereby releasing relay I30, by opening its circuit through the upper contacts of jack I2 I, before traced. Plugging in with cord circuit I I1, effects the insertion of the cord circuit conductors in series with the line and the attendant of position 3 can now communicate telegraphically with the originating distant attendant. When the plugs of cord circuits H2 and II I are withdrawn from jacks I09 and I2I there is no momentary opening of the transmission circuit, since the jacks are arranged so that the normal connection between the tip and sleeve conductors is established before either the tip or sleeve conductors are disconnected from the corresponding conductors of the withdrawing plug.

If the attendant at position 1 should be informed that a connection with position 2- is desired, then transfer key I I3 would be operated, thereby connecting battery with its left contacts through the winding of relay I2'I'to conductor I32, and with its right contacts ground to conductor I34. Secondary line relay I35 accordingly operates over conductor I28, through the uppermost contacts of jack I09, and in turn operates relay I36, through the upper normal closed contacts of jacks I20, I2I, I22 and succeeding jacks to ground I25. Relay I36 locks to battery through its inner contacts, and through its outer contacts lights lamp I3'I at position 2. If the attendant at position 1 should be requested to transfer the call to position 4, then transfer key H should be operated, which would extend battery through the left back contacts of key I I3, the left inner contacts of key H4 and left outer contacts of key H5 and the winding of relay I21 to conductor I32. The ground normally connected to the right inner contacts of key H3 would be extended to conductor I38, through the right inner contacts of key H4 and right outer contacts of key H5. The apparatus at position 4, associated with trunk I00, would now function in the mannerbefore described for the other positions-relay I39 operating, and in turn operating relay I40, which locks up and in turn lights lamp I4I. In a similar manner, incoming calls over trunk I00 would be transferred to additional positions, not shown, by means of additional transfer keys, similar to keys H3, H4, H5 which may be connected in the same manner as keys H3, H4, H5 are connected.

In the herein before given description, the Operation of the invention for calls incoming over trunk I00 has been discussed. The invention functions in a similar manner for the other trunks. Assume that the distant attendant calls over trunk IOI, causing thereby the momentary release of relay I42, the locking up of relay I43, andthe lighting of line lamp I01. When the attendant of position 1 plugs into jack H0, releasing relay I43 and extinguishing lamp I01, conductor I 32 is connected by the uppermost contacts of jack H0 to conductor I44. When one of the transfer keys, H3, H4 or H5, is operated battery is connected to conductor I32 through the winding of relay I21, and ground to conductors I34, I29, or I 38, respectively, causing thereby the lighting of the secondary line lamp, I45, I46 or I47, respectively. The invention functions in a similar manner for a call incoming over trunk I02. In general, it will be noted that the particular position to which an incoming call is to be transferred, is identified by the connection of ground to the corresponding positional conductors, namely, I34, I29, I38 by the associated keys, H3, H4, H5, respectively, and that the calling trunk is identified by the connection of conductor I32 to conductors I 28, I44, I48 by the uppermost contacts of associated jacks I09, H0, III, respectively.

Referring now to the other arrangement of the invention, Fig. 2 is similar to Fig. 1 except for the additional feature of providing two primary answering positions, positions 1 and, 2, at each of which is also provided secondary answering equipment. The primary answering lamps, 200 and 20I, 292 and 203 or 204 and 205 associated respectively with trunks 2| 1, 2| 8 and 2I9 at both of these positions are lighted simultaneously on incoming calls. As soon, as a call has been answered, at either position, both associated answering lamps are extinguished. The primary positions 1 and 2 are also provided with secondary answering lamps 206, 208, and: 2I0 and 201, 209 and 2H, respectively. The primary positions have sets of transfer keys, 2I2, 2I3, and 2M and 2I5, 256, and 251, respectively, with which an incoming call can be transferred from one primary position to the other, and from either primary position to the secondary position 3. Keys 2M and 257 may be used to transfer calls to a position 4 not shown, and illustrate how keys may be added to provide for additional secondary positions. A more complete understanding of this arrangement may be obtained from the following detailed description.

Let it be assumed now that an attendant at a distant office desires to communicate with the attendant of position 2, over the inter-city communication trunk 2". To initiate the call the distant attendant causes the momentary removal of ground 220, thereby opening the normally closed circuit which is traced from ground 220, over trunk 2 l7, through normally closed lowermost contacts of jack 223, winding of line relay 222, lower contacts of jack 225, lowermost contacts of jack 226, winding of line relay 22?, lower contacts of jacks 228, 229 and jacks at higher numbered positions, not shown, to battery 232 Relays 224 and 22? release simultaneously. Relay 224 in releasing closes a circuit from battery through the winding of relay 23l, middle normally closed contacts of jacks 223 and 226, and upper normally closed contacts of jacks 225, 228, 229 and similar jacks, not shown, of higher numbered positions to ground 232. Relay 23l operates and locks to battery through its inner contacts, and with its outer contacts lights line lamp 205 through an obvious circuit. Relay 227 in releasing closes a circuit from battery through the winding of relay 233, middle normally closed contacts of jack 223, thence over the circuit before traced for relay 23i to ground 232. Relay 233 operates and locks to battery with its inner contacts and with its outer contacts closes an obvious circuit through lamp 25 I which lights.

The attendants at positions 1 and 2, observing the lighted lamps 221i and 25!, endeavor to answer the call and plug in, respectively, with teletypewriter cord circuits 234 and 235. Let it be assumed that the attendant at position 1 plugs into jack 223, before the attendant at position 2 plugs into jack 225. As soon as the normally closed middle contacts of jack 223 open, the circuit before traced for relays 23! and 233 is opened. These relays release and extinguish lamps 200 and 25 I. The attendant at position 2, observing that lamp 25! is now extinguished knows that the call has already been answered at position 1 and does not plug into jack 225. The attendant at position 1 is now in communication with the distant attendant at the originating end of trunk 2H, who requests telegraphically that the call be transferred to position 2. This the attendant at position 1 now proceeds to do by operating the transfer key 2 82. A circuit is closed from battery through the outer left contacts of key 2 I 2, through the winding of relay 237, over conductor 233, through uppermost operated contacts of jack 223, over conductor 2451, through winding of relay 24!, over conductor 242, to ground on the outer right contacts of key 2i2. Relays 23l and 2M operate in this circuit. Relay 23? in operating lights pilot lamp 238 indicating to the attendant at position 1 that the transfer apparatus has operated and that key 2 l 2 may now be released. Relay 22! in operating operates relay 243 in a circuit through its contacts from battery through the winding of relay 2 13, upper closed contacts of jacks 228, 229 and jacks of other positions, not shown, to ground 232. Relay 2 23 locks through its inner contacts to battery, and with its outer contacts closes an obvious circuit through lamp 207 which lights. The attendant at position 2 now responds with teletypewriter cord circuit 235 by plugging into secondary answering jack 228. This opens the circuit of relay 243 before traced, which releases, extinguishing lamp 257. The attendant at position 2 is now in telegraphic communication with the distant attendant, since the conductors of cord circuit 235 are now in series with the line.

If the distant attendant should request that the call be transferred to'the attendant of some secondary answering position, say position 3, then transfer key 2i3 at position 1 will be operated and a circuit will be closed from battery through the inner left contacts of key 2 l2, outer left contacts of key US, winding of relay 231, over conductor 238, uppermost operated contacts of jack 223, over conductor 240, through winding of relay 2, over conductor 245, through outer right operated contacts of key 2l3, and inner right contacts of key 2|2 to ground. Relay 244 operates in this circuit and closes a circuit from battery through the winding of relay 266, upper normally closed contacts of jack 229 and similar contacts of jacks in other positions, not shown, to ground 232. Relay 246 operates and locks with its inner contacts to battery, and closes with its outer contacts an obvious circuit to ground through lamp 247, which is lighted.

In response to the lighted lamp the attendant of position 3 plugs into jack 229 with the associated positional teletypewriter cord circuit 235, which opens the circuit through the winding of relay 245, which releases, extinguishing lamp 247. The attendant of position 3 is now in communication with the distant attendant by means of cord circuit 235, the conductors of which were connected serially with the line when the plug of the cord was inserted into jack 229.

Let it be assumed that an incoming call over trunk 2 5? is answered at position 2, the attendant plugging into primary answering jack 225, in response to the lighted line lamp 205, and that it is requested that the call be transferred to position 1. Key 215 is accordingly operated and closes a circuit from batterythrough the inner left contacts of keys 2l2, 2E3, 2M, outer left contacts of key 2E5 and the winding of relay 258 to conductor 249, thence through the uppermost contacts of jack 225 to conductor 2%, through the winding of relay 255 to conductor 25f and ground on the outer right operated contacts of key 2l5, which ground is extended through the inner right contacts of keys 2l2, 2E3 and 2M. As soon as this circuit is closed by the operation of key 2E5, relays 2 58 and 255 operate. Relay 248 in operating, closes an obvious circuit through lamp 252, which lights as an indication that the transfer to position 1 has been satisfactorily effected. Relay 255 in operating closes a circuit from battery through the winding of relay 253 and upper contacts of jacks 225, 228, 225 and other jacks, not shown, to ground 232. Relay. 253 operates and locks to battery through its inner contacts and with its outer contacts closes an obvious circuit through lamp 255, which is lighted. The attendant at position 1, observing the lighted lamp 265, plugs into jack 225 which opens with its upper contacts the operating path of relay 253, which releases eXtinguishing lamp 205. The attendant of position 1 can now communicate over trunk 2H with the distant attendant. For a transfer of the call from position 2 to position 3, key 2E5 is operated and the invention then functions as in the case of the call transferred from position 1 to position 3, relay 2% and lamp 247 being lighted at position 3.

It should be pointed out that the effectiveness of the means provided for transferring calls is much increased by the method of wiring the transfer keys, so that the contacts of keys 2E2, 213, E24, 2H5, 2H5 and 2d? are all wired in series with battery and ground connected to the back contacts of key 2|2. With this arrangement if both attendants, at positions 1 and 2, respectively, should endeavor to transfer a call at the'same time, the transfer would be effected by the attendant at position 1, since the operation of any transfer key at position 1, disconnects battery and ground from the keys of position 2. Under l of calls incoming from a distant point.

referred to calls incoming over trunk 2H.

this condition, that is, while a transfer key of position 1 is operated, relay 24B cannot operate, and consequently lamp 252 does not light, thereby indicating to the attendant of position 2 that a transfer is being handled at position 1. Also to assure sufiicient time for relays in series with relay 237 or 248 being properly operated relays 231 and 248 are made slow operating.

The description for Fig. 2 hereinbefore given In like manner calls may be received over trunks 2I8 and 2 I 9, which also terminate at primary positions 1 and 2 and are arranged for transfer in the same manner as trunk 2 I I. In general, when a trunk is to be transferred from an answering position to another position and a positional transfer key is operated, the calling trunk is identified by the connection of battery on conductor 239 or 249, to conductors 240, 254 or 255 by the uppermost contacts of the associated answering jacks and the position to which the transfer is to be made is identified by ground on conductors 25I, 242, 245 or 256 connected thereto by the transfer key.

The invention has been described on the basis It will be understood, however, that the arrangement disclosed will function also for outgoing calls. The attendant at any position, primary or secondary, of Fig. 1 or Fig. 2 can originate a call by inserting the plug of a teletypewriter cord circuit into the jack at that position and then oper ating momentarily the break key of the teletypewriter circuit at the position whereat the call originates thereby causing terminating telegraph repeaters at each end, not shown but actually used, as stated hereinbefore, to operate and apparatus at the distant end to function and operate a line signal. This apparatus may be the same, or equivalent to that of Fig. 1 or Fig. 2, the line circuit being completed to the distant grounds, I03, I06, I05, 220, 22!, 222 through the winding of line relays, similar to those of Fig. 1 and Fig. 2'.

What is claimed is:

1. In a manually operated switching system, a switchboard divided into a plurality of sections, a plurality of two-way circuits for incoming and outgoing messages terminating at said switchboard and multipled toeach of the sections thereof, a primary signal lamp and a plurality of secondary signal lamps associated with each of said circuits and respectively located at said sections of said switchboard, and selecting means at each of said sections for transferring a signal displayed on the primary signal lamp at one section to a secondary signal lamp at any one of the other of said sections as desired, and a receiver at each of said sections whereby an incoming message may be received at any desired section,

2. In a manually operated switching system, a switchboard divided into a plurality of sections, a plurality of normally closed circuits terminating in said switchboard, a normally operated relay in each of said circuits and located at one of said sections, a plurality of spring jacks in each of said circuits, each of said plurality of spring jacks having an appearance in one of said sec tions, a signal lamp appearing in each of said sections and associated with one of said spring jacks, means at a distant point in each of said circuits for opening said circuits and effective to cause the release of said normally operated relay, a second relay at each of said sections associated with each of said jacks and responsive to the operation of said first-mentioned relay, a locking circuit for said second-mentioned relay, an operating circuit for each of said signal lamps arranged to light its associated signal lamp simultaneously with the'energization of its associated locking circuit, a cord circuit including a receiver at each of said sections for connecting said receiver to the line circuit corresponding to the lighted signal lamp, a keyset at each of said sections comprising a key for transferring the lighted signal at one section to a signal lamp at any one of the other of said sections.

3. In a manually operated switching system, a switchboard divided into a plurality of primary answering positions and into a plurality of secondary answering positions, a plurality of trunks for two-way messages terminating in said switchboard at each of said primary and each of said secondary answering positions, primary trunk signals individual to each trunk appearing at each of said primary positions, secondary trunk signals individual to each trunk appearing at each of said primary positions and also at each of said secondary positions, and means at each of said primary positions for transferring any primary trunk signal to any other of said primary positions or to any one of said secondary positions.

4. In a manually operated switching system, a switchboard divided into a plurality of primary answering positions and into a plurality of sec ondary answering positions, a plurality of trunks for two-way messages terminating in said switchboard at each of said primary and said secondary answering positions, primary trunk signals individuals to each trunk appearing at each of said primary positions, secondary trunk signals individual to each trunk appearing at each of said primary positions and also at each of said secondary positions a positional transfer signal at each of said primary positions, transferring means associated with each primary position for transferring a trunk signal to any other primary position or to any one of the secondary positions, and means for actuating said transfer signal in response to the functioning of said transferring means.

5. In a manually operated switching system, a switchboard divided into a plurality of primary answering positions and into a plurality of secondary answering positions, a plurality of trunks for two-way messages terminating in said switchboard at each of said primary and each of said secondary answering positions, primary trunk signals individual to each trunk appearing at each of said primary positions, and also at each of said secondary positions, transferring means associated with each primary position for transferring a trunk signal to any other primary position or secondary position, and means for preventing the simultaneous use of said transferring means at more than one primary position thereby preventing circuit interference.

ALLEN R. BONORDEN. FRANK J. CARTER. FRANK H. HANLEY.

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