US1276549A - Telephone-exchange system. - Google Patents

Description

A. E. LUNDELL.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED DEC. 26, I916.

Patented A11 20, 191&

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TELEPHONE EXCHANGE SYSTEM. APPLICATION FILED DEC. 26. 1916.

1,276,549. Patented Aug. 20, 1918.

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TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED DEC. 26. I916.

Patented Aug. 20, 1918* 3 SHEETSSHEET 3.

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ALBEN E. IZUNDELL, or NEW YORK,/1\T. Y., ASSIGNOR T0 WESTERN ELECTRIC COMPANY,

INCORPORATED, 0F NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

To all whom it may concern:

Be it known that I, ALBEN E. LUNDELL, a citizen of the United States, residing at New York, in the county of Bronx and State of New York, have invented certain new and useful Improvements in Telephone change Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to telephone exchange systems, and particularly to circuit arrangements for automatic telephone exchanges.

It is the object of this invention to pro vide an improved telephone system in which switching means, by which connections may be established between calling lines of various cha *acter and a called line, are variably operable for performing their connecting function, the various operations of the switching means being determined by the class or character of the calling line.

In semi-mechanical telephone exchange systems it is customary to provide, in association with one of a train of switches by which connection may be established between two lines, such as the connector switch, an interrupter by means of which the controlling operators supervisory lamp is flashed in case the desired line is found busy. In case it is required to combine such senii-inechanical systems with a full-automatic system, it will be necessary to control the operation of said connector switch from a subscribers station. In this case, in view of the fact that the calling station is not equipped with supervisory lamps, insteadof a visual busy signal, an audible busy signal is given for the purpose of conveying to the controlling party information of the busy condition of the desired line. The apparatus arranged to produce the audible busy signal is also associated with the mentioiied connector switch. The two busy sig naling apparatuses are permanently associated with the connector switch, and for this reason, in the latter mentioned case, due to the impulses sent by said interrupter. the connection established under the control of the subscriber may be mutilated. The sending of such impulses might result, for instance, in the undue actuation of a call register or meter associated with the line of a full automatic subscriber.

In order to prevent such interference with the proper operation of the system, accord- Specification of Letters Patent.

Application filed December 28, 1916. Serial No. 139,512.

ingto the present invention, means are pro.- vided whereby, depending on the character of the line calling (semrmechanical or full automatic), a plurality of busy signalin means p ermanently associated with a selectively operable switching device are alternatively rendered effective.

In the drawings, Figures 1 and 2, placed side by side, diagrammatically represent a semi-mechanical telephone system; and Fig. 3, taken together with Fig. 2, respesents a full automatic telephone system.

The automatic switches shown in the drawings may be of a structure similar to that shown in Patent 1,123,696 to E. B. Craft and J. N. Reynolds. The sender cord finder switch, indicated in Fig. 1, will ordinarily be provided with but a single set of brushes.

The sequence switches, hown in the drawings, may be similar to that disclosed in Patent 1,127,808. The numerals which appear adjacent to the sequence switch contacts, diagrammatically represented in various portions of the drawings, indicate the positions of the sequence switch at which these contacts are closed, with the exception that the controllingcontacts, one of which appears immediately above the motor magnet of each of the sequence switches, are opened only at the positions indicated by the numerals adjacent thereto and, therefore, the sequence switch can stop in only these positions.

s The circuits for controlling the operations of the various selector switches, and of the sender, are not disclosed in detail. The senders shown in the lower portions of Figs. 1 and 8, are of the revertive-impulse type disclosed in Patent 1,168,319 to A. E. Lundell. The sender shown in Fig. 1 and the various .selector switches are operable in the same manner as disclosed in the mentioned Patent No. 1,168,319. The control of the sender shown in Fig. 3 is performed by a full automatic subscriber. This control may be exercised in the manner disclosed in Patent 1,157,881, to F. R. McBerty, or in the manner disclosed in an application of Reeves and Lundell, Serial No. 72,908, filed January 19, 1916.

The structure and arrangement of the senders and selector switches has no bearing on the present invention, and instead of the senders and selectors described in the above mentioned patents, any other revertive impulse sender or selector switch may be used without departing from the spirit of the invention. Obviously, instead of a lGfGliZll'Q impulse sender, an impulse sender may be used by means of which the selector switches are directi ely set.

Only a general outline of the senoer arrangement shown in the mentioned patents is given in the drawings, and the operating positions of the sequence switches shown in Figs. 1 and 3 are different from those used in the cited patents. With reference to the sender shown in Fig. 1, the cord finder F, shown in Fig. 2 of the patent, is represented at 139, only two wipers, 138 and 126, and two terminals adapted to be engaged by the wipers being shown. These wipers correspond to the third and fifth wipers of the cord finder shown in the mentioned patent.

1n order to simplify the circuit shown in Figs. 1, 2 and 3 of the patent, a single circuit is shown extending between the sender and the controlling apparatus of the selector 115 where a plurality of circuits are shown in the patent. Only one sequence switch 113 is shown in 1 for performing functions which are usually performed by two sequence switches. This sequence switch therefore is a combination of the sequence switch 300 and shown in the patent. Under the control of a circuit including the conductor leading to the lefthand contact of sequence switch spring 117, the sequence switch 113 may be moved out of position 1. Sequence switch contact 116 is a combination of sequence switch contacts 206 and 208 of the patent, the mentioned conductor corresponds to conductor 305, and sequence switch spring 117 to sequence switch spring 30-1 ofthe patent. Relay corresponds to relay 309 of the patent. in order to simplify the circuits, this relay is shown as controlling the movement of sequence switch 113 out of position 1, although relay 309 does not perform this function. Instead of the energizing circuit including the right-hand winding of relay 309 of the patent, and the holding circuit including the left-hand armature and winding of relay 309, a single circuit is shown including the right-hand contact of sequence switch spring 117, and sequence switch spring 122. The conductor by means of which the two last mentioned sequence switch contacts are interconnected, corresponds to conductor 317, and sequence switch spring 122 to spring 209 of the patent. Belay 110 corresponds to relay toe, and relay 129 to relay tea. The conductor leading to wiper 126 corresponds to conductor 21%, sequence switch spring 125, to spring 215, and relay 123, to relay 212 of the patent. lhe conductor and s quence switch contact 23% of the patent, which are used when sending impulses beyond the selector shown in Fig. 1 of the patent, are left out, the last. mentioned conductor and sequence switch spring 125 being used for this purpose. l he conductor leading to wiper 138, by means of which sequence switch 113 may be moved into the talking position, corresponds to conductor 215 of the patent and sequence switch spring 137' to se quence switch spring 129 of the patent.

Establishment 07' a somii-mcchrmioal cowl L t io n.

A subscriber at station 100 desiring to obtain a connection with a subscriber at station 200 removes his receiver from the switchhook, whereupon his line is extended in any well-known manner to a cord oircuit 101. T he answering supervisory relay SR becomes energized. i i controlling operator at whose position the cord circuit 101 is provided, receives the order of the calling subscriber and communicates with a B oper= ator, whose controlling apparatus consists of the sender, by means of a well-known order wire circuit (not shown). The 13 operator instructs the A operator to extend the line through an idle trunk 102, 103 and 10%, whereupon the ii. operator inserts plug 105 into the jack 106, in which the assigned trunk terminates at her board. A circuit is closed thereupon from grounded battery through the winding of a relay 10?, the sleeve contacts of plug 105 and jack 106, conductor 10 1, and the winding of a slowtorelcase relay 103, to grounded battery. Belay 101- closes a circuit from ground through its armature and front contact, the back contact and armature of a calling supervisory relay Soil and a supervisory lamp to grounded battery, whereupon this lamp is lighted. rlelay 108 closes a circuit from ground through its a-rn'iature and front contact and the windin of a relay 109 to grounded battery, causing thus the energization of this relay.

The 13 operator writes down the number of the desired subscriber on her keyboard (not shown) determining thus the operation of the counting relays. In the drawings only the zero counting relay 10 is indicated. The B operator depresses also an assignment key 111, closing thus a circuit from ground through the contact of this key, the upper contact of a sequence switch spring 112, and the power magnet of a sequence switch 113, to grounded battery. The sequence switch is moved out of position 1 and under the control of its normal contact 11-1 into position 13. While the se quence switch is moving from position 1 to position 13. the setting of a selector switch accomplished under the control of the sender, this sender being connected to the controlling circuit of the selector 115 by means of a cord finder 139 in the saniemanner as described in the mentioned patent to A. E. Lundell. When the sequence swltch 113 reaches position 2 a circuit is closed from ground through a sequence.

switch contact 116, the left-hand contact of a sequence switch spring 117 (controlled by a sequence switch 118), and the winding of av relay 119, to grounded battery. Relay 119 closes a circuit from ground, through its armature and front contact, the left-hand contact of a sequence switch spring 120, and

. the power magnet of sequence switch 118,

to grounded battery, whereupon the sequence switch 118 is moved out of position 1 and under the control of its normal spring 121, into position 13. While the sequence switch 118 is moving from position 1 to po sition 13 the above mentioned setting of selector switch 115 is controlled by the sender.

\Vhen the sequence switch 118 moves out of position 1, the relay 119 is held energized by a circuit extending from grounded battery, through its winding, the right-hand contact of sequence switch spring 117, and the contact of a sequence switch spring 122, to ground.

As soon as sequence switch 113 reaches position 12 a circuit is closed from grounded battery through the winding of a relay 123, the upper lefthand contact of a sequence switch spring 12st, a sequence switch ,contact 125, cord finder brush 126, a sequence switch contact 127, a resistance 128, windings of a stepping relay 129, and the back contact.and armature of the zero counting relay 1.10, to ground. Relay 123 becomes energized and closes a locking circuit for itself through its right-hand front contactand armature, and the lower contact of sequence switch spring 12%. Relay 123 closes also a circuit from ground, through its lefthand armature and front contact, the lower contacts of a sequence switch spring 130, a selector wiper 131, a conductor 200, the upper right-hand and lower left-hand contacts of a sequence switch spring 201, and the winding of a relay 202, to grounded battery. Relay 202 closes circuit from ground, through its left-hand armature and front contact, the upper right-hand and the lower left-hand contacts of a sequence switch spring 203, and the winding of a relay 20%, to grounded battery. Relay 20% becomes energized and closes a locking circuit for itself from grounded battery through its winding, right-hand front contact and armature, a resistance 205, a conductor 206, a selector wiper 132, a resistance 133, and the upper contact of a sequence switch spring 1341, to ground. The relay 204 closes also a circuit from ground, through its lefthand armature and front contact, the upper right-hand contact of a sequence switch spring 207, and the power magnet of a sequence switch 208, to grounded battery.

Sequence switch 208 is moved out of position 1, and, under the control of its normal sprin 209, into position 6. hile the sequence switch 208 is moving through the positions 2, 3, 4 and 5, and before the sender sequence switch 118 reaches position 13, the connector 210 is controlled in accordance with brush tripping impulses, and impulses representing the tens digit of the desired subscribers number.

As soon as the sequence switch 208 moves out of position 1 the originally traced circuit of relay 202 is opened, but this relay remains energized by current flowing through a circuit traceable from grounded battery through its winding, the upper contact of a sequence switch spring 211, the right-hand front contact and armature of relay 202, and the upper contacts of sequence switch spring 201 to ground at the left-hand armature of relay 123. This ground is also extended through the lower contact of sequence switch spring 211, conductor 212, and winding of a magnet 213, to grounded battery. By attracting its armature, magnet 213 presses a brush rod 21% of the connector 210 against a roller 215 constantly rotating in the direction indicated by the arrow. lVhenever a brush 216, carried by rod 214, engages the conducting plate 217, a circuit is completed from ground, through the left-hand armature and front contact of relay 202, the up per lefthand contact of a sequence switch spring 218, a conductor 219, brush 216, conducting plate 217, a conductor 220, the contact of a sequence switch spring 221, the upper contact or" a sequence switch spring 222, conductor 223, selector wiper 135, the right-hand contacts of sequence switch spring 12a and the right-hand armature, front contact and winding of relay 123, to grounded battery. Due to the closure of this shunt path to the winding of relay 123, the stepping relay 129, which was energized in series with relay 123, becomes deenergized and permits the actuation of the first counting relay, as determined by the setting of the units keys in the operators keyboard. The above traced shunt path is opened as soon as the wiper 216 engages an insulating segment 224 in the conducting plate 217, and thus the relay 129 is permitted to reenergize. After the connector 210 has been moved in an upward direction by a required number of steps, the counting relay 110 becomes energized and opens in its back contact the circuit of relays 129 and 123, whereupon these relays become de'energized. The relay 110 closes a circuit through its front contact and sequence switch contact 136, for moving the sequence switch 118 out of position 13 and into position 16, whereupon a circuit is closed from ground through a sequence switch contact 137, cord finder wiper 138, the lower contact of sequence switch spring 112 arlc the power magnet of se quence switch 11 to grounded battery, for moving this seq once switch out or posiosition 1-2. in response to LllQ deenergization oi relay 123, relay 202 and magnet become deenergized, whereupon the connector rested with its wipers 29, 230, on terminals or the desired line.

in response to the deenergization oi the relay 202 a circuit is closed from ground, through the upper left-hand and lower right-hand contacts of sequence switch spring 203, and the power magnet of sequence switch 208, to grounded battery :tor moving this sequence switch out of position 6, whereupon the sequence switch moved under the control of its normal contact 200 toward position 1%.

in case the line of the desired subscriber is idle, full battery potential exists on to terminal oi this line. is soon as tl sequence switch 208 reaches position 3 a the circuit closed from ground, througn high resistance lower winding of a margina testrelay 220, the lower contzcts of a sequence switch spring 22?, the low resistance upper w' iding of the relay a sequence switch contact 223. test wiper 229, terminal 225, and the winding of a cut-oil relay C9 of the desired line, to grounded battery. Belay 220 becomes energized and closes a circuit: from ground, through its upper armature, front contact and low resistance winding to grounded battery. atthe cut-oil relay CO, reducing thus the potential on the multiples of test terminal 225 for preventing the seizure of this line by another connector switch 210 in a manner to be hereinafter set forth. The sequence switch 208 will not be arrested in position 14-, because as soon as it reaches th" position it will be driven into position i by current llow ing from grounded battery through its power magnet, lower rig it-hand contact oi sequence switch spring 207 and the lower front contact and armature of relay 2%, to ground.

As soon as the sequence switch 113 reaches position 1i a circuit is closed from. grounded battery, through the power magnet oi set uence switch 113, left-hand contact of a sequence switch spring 110, the front contact and armature 0t relay 109, and the lower contact of sequence switch spring l l-l, to ground. The sequence switch 113 is thereupon moved into position 10. llhen it reaches this position, a circuit is closed from grounded battery through a sequence switch contact 1 11, the armature and back contact of a marginal relay lei-2, the back contactand armature of a relay 113, the winding of a relay Li t, a sequence switch contact l lo, and the front contact nd armature of re lay 108, to ground. Relay lli becomes energized. Relay cannot? become energized in parallel with the relay ill, due to the tact that its winding is short-circuited through the armatures and back contacts of relays 1&2 and 113. Upon the energization of relay lit a circuit is closed from ground through a ringing machine 14:6, the winding or relay 1422,21 sequence switch contact 1%, the lower frontcontact and armature of relay list, a sequence switch contact 1&8, selector wiper 135, conductor the righthand contacts of sequence switch spring 22-2, connector wip r 230, the hell at the called substation, connector wiper 231, the righthand contacts of sequence switch spring 201, conductor 200, selector wiper 131, the righthand contacts of sequence switch spring 130, and the upper arn'iature and front contact of relay li t, to ground. The bell at the called substation is actuated and as soon as the called subscriber removes his receiver from the switchhoolr the marginal relay 11 :2 becomes energized, opens the circuit of relay Hi and the short circuit around the winding of relay H3, whereupon this relay becomes energized and short-circuits relay ill. The energizing circuit of relay 1&3 may be traced in the same manner as that of relay 14:1.

in response to the removal of the switchhoolr at the called substation, the superrisory relay SR becomes energized and opens a circuit of lamp SL, whereupon this lamp is extinguisned.

ll hen the calling and called subscribers desire disconnection and restore their receivers to the hook switches, the circuits of the supervisory relays and SR are opened. Due to the det'nergization of relay SE, the lamp SL is again lighted, whereupon the A operator removes plug 105 from jack 106. lays 107 and S become deenergized. The lamp SL is extinguished, and relay 109 becomes de'e'nergized and closes a circuit from grounded battery, through the winding of a relay 150, the back contact and armature of relay 109, and the lower contact of sequence switch spring 13 1, to ground. The relay 1-50 becomes energized and after a certain time interval (this relay being slow to pull up) it closes a circuit from ground, through its front contactand armature, the right-hand contact of sequence switch spring 1'0, and the power magnet of sequence switch 113, to grounded battery for moving this sequence switch out of position 16 and into its normal position. ll hile the sequence switch is moving to its normal position the selector 115 is released to normal. Upon the deenergization of relay 108, relay also becomes deenergized.

Upon the restoration of selector 115, relay -1 becomes deenergized and closes a circuit from ground, through its left-hand armature and back contact, the upper lefthand contact of sequence switch spring 207,

and the power magnet of sequence switch 208, to grounded battery, for moving this sequence switch out of position 16 and into position 18. A circuit is now closed from grounded battery, through the winding of the magnet 251, conductor and the upper right-hand and lower left-hand contacts of sequence switch spring 218, to ground. The magnet 251 by attracting its armature presses brush rod 214 against the roller 253, constantly rotating in the direction indicated by the arrow, whereby the connector is released to normal. As soon as a brush 25%, carried by the brush rod, reaches a nor mal conducting segment 255, a circuit is closed from ground, through the lower con tact of sequence switch spring 218, conductor 219, brush 25 i, conducting segment 255, conductor 256, the lower left-hand contact of sequence switch spring 207, and the power magnet of sequence switch 208, to grounded battery, for moving the sequence switch out of position 18 and into position 1. The magnet 251 becomes deenergized, the relay 226 being deenergized since the sequence switch 208 left position 16.

In case the desired subscribers line is busy the potential on test terminal 225 and multiples thereof is reduced. For this reason, upon the engagement of terminal 225 by wiper 229, the marginal relay 2126 does not receive suilicient current to permit its energization. When, therefore, the sequence switch 208 reaches position ll, in the above described manner, due to the denergized condition of relay 226, no circuit will be closed through the lower right-hand contact of sequence switch spring 207, and thus the sequence switch stops in position let. A circuit is now closed from ground, through the lower armature and back contact of the test relay 226, a sequence switch contact 257,

conductor and the winding of magnet 251, to grounded battery. The magnet 251 causes the release of the connector in the same manner as above described and when the brush 25% engages the normal conducting segment 255, the circuit through the lower left-hand contact of sequence switch spring 207 is closed and the sequence switch 208 driven out of position 1e and into position 17. A circuit is now closed from ground through a constantly operating interrupter 258, a resistance 270, the upper contact of sequence switch spring 227, conductor 223, selector wiper 131. sequence switch spring 1&8, the lower contact of relay 1 1i, conductor 103, the ring contacts of jack 106 and plug 105. the winding of the supervisory relay SR and the secondary winding of the repeating coil, to grounded battery. The supervisory relay SR is intermittently energized and deenergized and causes thus the flashing of lamp SL. The controlling operator, noticing the flashing of lamp SL,

informs the calling subscriber of the busy condition of the desired line and causes the restoration of the selector switch 115 in the same manner as above described.

Eatubli-slmzcut of a full-automatic connection.

A subscriber whose station is indicated at 300 may control the establishment of connection between his station and station 200 through a line finder 301, a selector 302 and the connector 210.

Cord circuits, such as the ones shown in Fig. 3, terminate at one end with the line finding switch 301, and at the other end with the selector switch 302, both being of the panel type, as previously stated. Upon the initiation of a call by any one of a plurality of full automatic subscribers whose lines terminate in the panel bank traversed by the brushes ot' the switch 301, a preselected switch 301 is caused to immediately move to and select the terminals of the calling line. The calling subscriber will thereupon actuate the sending device at his station to reg= ister the desi nation of the line wanted in the register sender which was preselected and operatively associated with the line finder prior to its actuation.

The setting of selector 302 is accomplished in substantially the some manner as the setting otselector 115, with the difference that the sender is set for operation under the control of the calling subscriber. During the movement of selector 302 the sender will receive impulses in accordance with its setting.

The selector 302 is setto seize the connector 210 through conductors 270, 271 and 272. ii pon the seizure of the connector, the relays 202 and 201 operate in substantially the same manner as above described and, under the control of the sender shown in Fig. 3, the connector switch is set to seize the called subscribers line. If this line is idle, then the sequence switch 208 is arrested in position 16 and ringing current is applied to the called subscribers line from a source (not shown) associated with the selector 302.

Upon the removal 01": the receiver at the called station, the supervisory relay 30a becomes energized and closes a circuit for energizing a relay 305, whereupon this relay locks up through a circuit closed through its right-hand front contact and armature and an off-normal contact 306 of the selectorswitch 302.

Then disconnection is desired, the calling and called subscribers hang up their receivers, and in response to the denergization of the supervisory relays 303 and 30%, the connection is severed in the well-known manner. Relay 305 being maintained en ergized until the selector 302 reaches its normal position and opens the off-normal Cit contact 2366 upon the dcenergization of the supervisory relay 304:, a circuit is closed from ground through the armature and back contact of this relay, the left-hand -front Contact and armature of relay 305, the line finder 301, and the winding of a netSO? to grounded battery. upon energization, actu known message register It the desired line is found bus y, then the connector 210 is released in the above described manner in position ll of sequence switch 208, and the sequence switch is moved into position 1?. Due to the fact that the selector 302 did not engage the conductor leading to the connecto 210, in position I? ot the uence switch 208. the ground interniittentl v applied to tt'" conductor will not affect the super "oi-v relay 30i. Should the supervisory lay be ope 'ated under the control oi interrupter 258, the magnet 30? would be actuated to operate the message register, although the desired line was busy,

in position 17 of the sequence switch 208, a tone is applied from a source through an induction coil 27%, condenser 275, the lower contact of a sequence switch spring 276, conductor 2'11, and thence through the repeating" coil 310 to the calling subscribefs station. indicating to him the busy condition of the line, whereupon he causes the releasing oi? the l n tinder and the selector by the hanging; up 0 his receive):

Whatis claimed is:

1. In a telephone system. two groups oi lines, a called line, u'ieans for extending a *alling line of either group to said called line, two characteristic busy signaling means, and'nieans depending on the ,g'roup to which an extent l calling line belongs t'or operativelv associating therewith a certain one of said signaling means.

telephone system, groups of lines, a called line, a switch for connecting any one of said lines when calling to the called line when idle, two busy signalingapparatuses of different character associated with said switch, means for connecting onlv one of said apparatuses to calling lines belonging to one of said groups, and means for connecting onl the other apparatus to calling-lines to the other group.

3. in a telephone stem, groups of lines, a called line, a selectively operable s vitching' device ope *able to seize said called line,

in a

operator controlled means for extending ct one group to said calling lines device,

- cacn, s

l. In a telephone system, a pluralit 0t ies of various character, anotner line, chin means, means tor actuating the c for connecting any one of said plurah v of lines to said other line, a signaldevice associated l'il'll said switching rug devic means ope 'ative in response to the actuation of said switching means to connect a line of a certain character for etl'ectively associating said signaling device with said last nientioi ed line, and means for preventing the operation of said last mentioned means wh said switching means is actuated to connect a line of a certain other cha 'acter.

5. In a telephone s stem, two groups of lines, a selectirel} operable switch, lines terminating" thereat, means for rendering said last mentioned lines busy, means for extendi any of the lines of said groups to said itch, a subscriber-s *alling device associated with each line of the first group, an operators sender, means for associating said sender with an extended line of the other group, means alternatively operable by a calling device and said sender tor causing said selector switch to seize a desired idle line terminating thereat, means operative in response to the busy condition of said desired line for preverting t ne successful operation of said last mentioned means, a constantly operating interrupter and a con stantly operating tone producing device associated with said selectivel; operable switclnmeans operative in response to an Hr uccesstul operation of said switch for sin'niltaneously preparing said interrupter and tone producing device for connection to a line extended to said selectively operable switch, means for connecting only said tone producing device to an extended line belongin to the first group, and 'means for connecting only said interrupter to an extended line belonging to the second group.

in witness whereof, I hereunto subscribe my name this 28th day of December A. D,

Sommisaioncr or adsir icing

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