US2418609A - Telephone system - Google Patents

Description

April 8, 1947. J. H. voss EIAL TELEPHONE SYSTEM Filed 001:. 25, 1944 2 Sheets-Sheet 1 INVEN-TORs. HERBERT E OBERGFELL EOEASED BY AMANDA OBERGFELL EXEOUTRIX 4mm u. voss ATTORNEY 2 Sheets-Sheet 2 I I I I l I l I I l I I p N m 8 S J INVENTORS.

HERBERT F OBERGFELL, DECEASED BY AMANDA OERGFELL,EXECUTRIX J. H. VOSS ET AL TELEPHONE SYSTEM Filed Oct. 23, 1944 April 8, 1947.

on n 5 Q l I I l I I I L 8m mun/r m n in mi 3m 7 I I III I l l J $1 N. 3 N Twwm H5: 1| 9% u 228 mwoz E K an 9m Iii..- 3 d3 6 on JOHN H. voss BY l I ma I Patented Apr. 8, 1947 UNITED STATES PATENT OFFICE TELEPHONE SYSTEM ware Application October 2-3, 1944, Serial No. 559,878

Claims. 1

The present invention relates in general to automatic telephone systems and more particularly to improved circuit arrangement for interconnecting a subscribers push-button calling device with a mechanical dial repeater which is individual to the subscribers line.

The main object of the present invention is the provision of improved impulsing circuits for translating coded digits received from a code sending calling device to cause the operation of an impulse receiving and registering device to store and retransmit the translated digits.

Another feature of the invention relates to the circuit arrangements whereby the impulse receiving and registering device, which is individual to the Subscribers line, is arranged to receive and store the digits transmitted by the calling subscriber while a finder switch is hunting for the calling line after whichthe stored digits are transmitted to the automatic switch train. With this arrangement the calling subscriber can immediately dial, or key, the called subscriber's number without waiting for the customary dial tone to inform the subscriber that he may start dialling.

Another feature relates to the improved impulsing circuits whereby false operation of the impulse receiving and registering device is prevented when the subscriber initiates a call, answers a call or disconnects by replacing the receiver.

Other features of the invention relate mainly to further detail circuit improvements and will be apparent in the following description and in the claims.

These circuit improvements, along with the push-button calling device, being claimed in a copending application Ser. No. 551,010, filed August 24, 1944, and the mechanical dial repeater, being claimed in a copending application Ser. No. 554,912, filed September 20, 1944, was designed primarily for use by a subscriber who originates a large number of outgoing calls, such as a salesman or an order clerk. Such a subscriber may set up, or key, the digits of a called number without waiting for the automatic telephone switches, such as finders, to find the calling line, and may proceed to call the desired called party as soon as the receiver is removed from the cradle of the desk telephone. The push-button calling device is arranged to transmit loop and ground pulses over the subscribers line to a pair of line relays which translate these incoming impulses into ground pulses to operate the impulse receiving and registering device. Each line relay controls a separate pulsing circuit and each such pulsing circuit extends to a stepping magnet in the impulse receiving and registering device. Each of these stepping magnets singly, or in combination, control the stepping of a selecting arm; such.selecting arm being stepped one step for each magnet operation. On each loop impulse transmitted from the calling device, both line relays are operated to simultaneously control the two separate pulsing circuits thereby operating both stepping magnets to operate the selecting arm a distance of two steps. A ground pulse transmitted from the calling device causes only one of the line relays to be operated while the other is maintained thereby only one of the separate pulsing circuits is completed to operate only one of the magnets to step the selecting arm only one step. The selecting arm is moved a number of steps corresponding to the translated digits to select and displace a pin in the path of the sending arm in the impulse receiver and registering device, or mechanical dial repeater. The successive digits are stored and marked by the displaced pins.

When the finder switch finds the calling line and connects the associated selector switch to the calling line, a circuit is completed for causing the impulse receiving and registering device to start the transmission of outgoing impulses in accordance with the stored digits. A plurality of relays are operated to transmit the outgoing impulses and at the same time transmit a pulse to the sending magnet for each outgoing pulse. The sending magnet operates an arm step-by-step until such arm encounters the first displaced pin at which time the relay operations are stopped momentarily to operate a pin restoring magnet which restores the displaced pin. After the pin is restored the relays again transmit outgoing pulses and operate the sending magnet until the arm encounters the second displaced pin. T is same cycle of operations continues until all displaced pins are restored at which time the stored digits would all be transmitted. The outgoing impulses operate the automatic switches to complete the desired connection.

Referring now to the drawings:

Figures 1 and 2 diagrammatically show the circuits by means of which the push button calling device and mechanical repeater control standard automatic telephone switches to complete desired connections.

Referring now in detail to Figures 1 and 2, the push-button calling device diagrammatically Number 551.010 filed August 24, 1944. The same.

reference characters as used in the drawings showing the detail construction of the push. button calling device in the above-mentioned copending application are alsoused'irrthe'circuit" diagram.

The substation circuit is. connected. by line.

conductors 2; and Eli! to individualcircuits. at. the main exchange. These circuits include a ring-control relay 2|5, a pair of line relays, a

repeating coil RC and other control relays; Some 1944. The same. reference characters'as applied r to the drawings showing the. detail. construction of. the. mechanical repeater. in the above-mentioned copending application are also. applied to. the circuit diagram.

.Theconnector multiples. Conn, Mult. are connected to'the lineand test conductors 35B, 33! and 302- andare accessiblev to regular. standard connector switches. in the main automatic.

exchange. I

Line: conductor. 300 isnormally connected to linev relay 3m in. the. usual manner while line conductor 3M is connected to an..open circuit at contact 32'! instead. of the. usual ground connection for a. purpose which. will be morefully describedhereinafter. The usual line cut-01f relay 32 3. isprovided and. is. operated on bothin'coming and outgoing calls. The. circuits, terminate in finder bank contacts 33l to 334', inclusive, which are multiplied; and accessible to standard finder switches, such as finder 34D. These. finders are of the. standardvertical and. rotary type of Strowger: finders having a. vertical motion. to find the bank level containingthe calling line and a rotary motion to. find the calling, line in the bank level; A. distributor switch, such; as. distributor 350, is associated with the, group of finders. for controlling. the same to. find the .calling line. The finders and distributor switch. are. of the general type such. as. shown in the Saunders .Patent. 1,849,694 issued. March 15,1932. A selectorv switch, such as selector 350, is tied tailto tail with each finder andhas access to other selectors or connector switches. in the usual manner dependent upon the capacity of. the automatic exchange. The selector is. of. the well-known type of Strowger selector having directive vertical movement to select. a. group. of. trunks and automatic rotary movement toselect anidletrunk from the selected group. Only line. relay 3.18 of selector 363 is shown for the purpose of explaining the control of impulse transmission start relay 240 which operates whenthe finderswitches through to the selector. to start retransmission of. the. digits storedi'n the mechanical di'al'repeater.

Having briefly describedthe. circuit layout a detail description will now be given. The calling subscriber will. remove the telephone handsetin- ,cluding. the. receiver. R and. transmitter T from the cradle and dial, or key, the digits of the called subscribers number. As is customary in multi-ofiice areas, the push-button calling device would be equipped with letters as well as digits on the push buttons and the calling subscriber would key the. letters of the exchange and then the digits of the called subscribers number in that exchange. Since this subscribers line is equipped with an individual dial repeater, the subscriber need: not wait for the customary dial tone but may start dialing immediately.

In response to the removal of the handset from the cradle,.cradlespring 2 I! disconnects the ringer R, cradle spring" 2|6 closes a point in the talking circuit, andcradle spring 2l5 completes a loop circuit through the substation circuit over the line conductors H8 and 2H, back contacts and armatures 2I-Iand 2l 2, through the left hand windings of repeating coil RC and through the windings of line relays 22!! and 230 to ground and battery for energizing line. relays 225 and 233. At front contact 23! relay 230' completes a circuit for energizing slow-to-release relay 260. At back contacts 2tl relay 263 disconnects ring control relay 2m and front contacts ZBI completes a circuit" for energizing line relay 3"] as follows: from ground at contacts 242, contacts 225-, through the right hand winding of repeat.- ing coil RC and resistance R2, front contacts 26I, conductor 38!), contacts 321 and the winding of line relay-313 to battery. At front contacts 262' relay 2'63 prepares a circuit for impulse transmission start relay 253 which circuit, however; is not completed until the finder switche through to the selector and at contacts 233', 254', 265 and 251 prepares circuits utilized in the impul'sing circuits to rotary stepping magnets RMZ and RMI. At contact 26B're1ay 23B disconnects ground from conductor 308'.

Relay 3H], upon energizing, atcontacts 313 grounds the vertical bank contact 334 and extends groundthrough the start resistance Rl to operate distributor 350 which in turn starts an idle. finder in search. of the calling line. At contacts 3H2", line relay 310, grounds conductor 302 and the multiples of connector test termina'ls to busy this line. to the connectors and at contacts 3| 1' marks the finder bank 333 and its multiples with calling potential through the windingofcut-off relay 323,

The calling subscriber need not wait for. the customary dial tone, which is ordinarily transmitted to the calling line as soon as the finder switches through. to the. selector. During the tim'e'the finder i searching for the calling line the calling subscriber may dial, or key, the digits of the called number. Assuming that the first digit dialed is an even number, digit 6 for example, the rocker arm and its insulating plate 43 are operated, as described in the copending application Ser. No. 551,010, in. response. to the downward stroke of key 6 to separate. springs'lfl thereby disconnecting, ground from springs 13. Also in response to the downward stroke of key 3, the clutch arm 6.6 is rotated ofi normal thereby causing. the closure of shunt springs H which closes the usual shuntaround the substation set and the clutch pawl slides over the next three adjacent teeth on the ratchet wheel. When. key 6" restoresthe clutch returns to normal and rotates the impulse shaft andimpulse wheel 78 a distance of three teeth thereby actuating spring 80 three times to separate contacts 82 three times. Contacts 82 interrupt the, loop circuit extending toline relays. 220. and. 230 three timestoicause three successive deenergizations and energlzations of both line relays. The closure of contacts 13 during the transmission of the last impulse is ineffective at this time because grounding sp 19 are open.

Each time line relay 229 deenergizes a circuit is completed for operating relay 295 as follows: from ground at back contacts 22I, contacts 261 and 283 and through the winding of relay 295 to battery. Relay 295 at contacts 296 prepares a circuit for relay 289 and at contacts 291 completes a temporary locking circuit for itself. This locking circuit may be traced from ground at contacts 265, contact 291 and 283 to relay 295.

Each time line relay 239 deenergizes a circuit is completed for operating relay 299 as follows: from ground at back contacts 23I, contacts 294 and 214 and through the winding of relay 299 to battery. Relay 299 at contacts 29I prepares a circuit for relay 219 and at contacts 292 completes a temporary locking circuit for itself. This locking circuit extends from ground at contacts 263 by way of contacts 292 and 214 to the winding of relay 299. At front contacts 23I line relay 239 temporarily opened the circuit to slow-to-release relay 269 but this relay, due to its slow-torelease characteristics, maintains its armature attracted during the impulsing period.

When the loop circuit is closed at contacts 82 line relays 229 and 23I reenergize. Relay 229 at front contacts 22I completes a circuit for energizing pulse relay 289 by way of contacts 296 and relay 239 at front contacts 23I again completes the circuit to relay 269 before it could fall away as well as completing a circuit for operating pulse relay 219 by way of contacts 29L Relay 289, upon energizing, at contacts 28I grounds conductor 394 to energize sloW-to-release relay 284 and rotary stepping magnet RMI. At contacts 282 relay 289 completes a temporary locking circuit for itself from grounded contacts 265 by way of contacts 282 and 296. At contacts 283 relay 289 opens the locking circuit to relay 295. Relay 219, upon energizing, at contacts 21I grounds conductor 393 to energize rotary stepping magnet RM2. At contacts 213 relay 219 completes a temporary locking circuit for itself from grounded contacts 263 by way of contacts 213 and 29L At contacts 214 relay 219 opens the locking circuit to relay 290. Rotary magnets RMI and RM2 in energizing position their pawls preparatory to stepping the pin setting arm I59 on the selecting member of the mechanical dial repeater.

Relays 219, 289, 299 and 295 are each arranged to restore their armatures within a predetermined time limit when their individual locking circuits are opened in order to correctly pulse the rotary magnets RMI and RM2. This timing being independent of the time ratio of the make and break connections at contacts 22I and 23 I.

Relays 299 and 295 deenergize when their locking circuits are opened by the energization of relays 219 and 269. Relays 299 and 295 at contacts 29I and 296 open the locking circuits of relays 219 and 289 to cause the release of the latter relays. 1A1; contacts 21I and 28! relays 219 and 289 disconnect ground from conductors 393 and 394 to release magnet RM2 and RMI to simultaneously step both magnets. While the circuit to relay'294 is interrupted at contacts 282 this relay, due to its slow release characteristics,

maintains its armature attracted during each' ..s81i es of; incoming pulses. In response to the deenergization of both magnets RMI and RM2, the selecting mechanism and pin setting arm I59 are rotated from its last occupied position a distance corresponding to two steps, or from above one pin, such as pin I69, past the next adjacent pin to above the next subsequent pin. Therefore, in response to a single loop pulse, line relays 229 and 239 cause magnets RMI and RM2 to move pin selecting arm I59 two steps to select the second pin from its last occupied position. In the present example, since the key 6 has been actuated, three loop pulses are transmitted to line relays 229 and 239 to control the relays 219 and 289 in a manner similar to that above described, to simultaneously operate both mag nets RMI and RM2 three times. These three simultaneous operations of magnets RMI and RM2 step the pin setting arm I59 six step from the last occupied position to a new position above the sixth pin for the incoming digit 6 Series relay 284 deenergizes shortly after the third, or last, release of pulse relay 219 for this digit and at front contacts 286 opens the circuit to slow to release relay 285 which maintains its armature attracted for a short interval. During this short interval a circuit may be traced for energizing the pin setting magnet PSM as follows: from ground at back contacts 286, contacts 281, conductor 395 and thru the winding of pin setting magnet PSM to battery.

Magnet PSM momentarily operates its arma ture I21, the rod I99 and pin setting arm I 59 to displace this selected sixth pin I99 to position it in the path of arm I99 of the sending member. Shortly after relay 294 releases relay 285 also releases and opens the circuit to magnet PSM which restores. Pin setting arm I59, the rod I49 and armature I21 are restored in response to the release of magnet PSM. It should be mentioned that as soon as the pin setting arm I59 is moved from its last occupied position, or the position corresponding to the occupied position of arm I99, cam IN is rotated in unison with arm I59 and therefore cam I1! permits contacts I93 and 194 to close thereby preparin a circuit for controlling the retransmission of outgoing impulses. Transmission of these impulses, however, do not take place until the selector 369 is connected and ready to receive such impulses. All of the above circuit operations have taken place in response to the actuation and release of key 9.

Assuming that the next, or second, digit dialed is an odd number, digit 5 for example, the rocker arm and plate 49 are operated in response to the downward stroke of key 5 to permit the closure of springs 19 thereby connecting ground to contacts 13. The shunt springs 1! are again closed during the time the clutch is off normal and the impulse shaft and impulse Wheel 18 are rotated a distance corresponding to three steps, or three cams of the impulse wheel 18, when key 5 restores. The impulse wheel 18 transmits two loop impulses and a ground pulse in this case because springs 19 are closed and are therefore effective when springs 13 close during the last impulse to change the last transmitted impulse from a loop to a ground impulse. Arm 11 is operated on the return operation of the clutch to close springs 13 during transmission of the last impulse in each series. During the transmission of the last pulse for each odd digit a circuit may be traced for maintaining line relay 239 energized while line relay 229 deenergizes. This circuit may be traced as follows: from ground at contacts 19, closed on all odd digits, contacts 13 closed on only the last pulse of each series, springs 89 and 8|, shunt springs 1i, conductor 2l8', back contacts 2| I, upperzleit-hand winding of repeat coil RC and through the winding of line relay 23% to battery. Therefore, line relay 220 deenergizes three times and line relay 233 deenergizes only twice whenever the number 5 digit key is actuated and released. Rotary magnet RMI is therefore operated. and. released three times while rotary magnet RMZE' is. operated, and released two times thereby stepping pin setting arm I53 equivalent to five steps to select another pin in the manner similar to that previously described.

Relays 284 and 235 again operate, after transmission of the last pulse for digit 5, to momentaril'y operate the pin setting magnet PSM which in turn operates the pin setting arm I51! to displace the last selected pin I31! into the path of arm 1'93.

Subsequent digits are transmitted and registered in the mechanical dial repeater in the same manner as above described, it being remembered that loop impulses are transmitted for each even numbered digits and that both loop and a ground pulse are: transmitted for each odd digit. For example,v five loop impulses are transmitted from the calling device to line relays 22B and 230 for the digit 0, the line relays translating these five impulses into ten pulses to magnets RM l and RMZ, five to each magnet, for causing the mechanica-l repeater to take ten steps to select and operate the tenth pin. For the digit 9 four loop pulses, followed by a ground pulse, are transmitted fromthe calling device to line relays 223 and 238 to operate rotary magnets RM! and RM2 In this case magnet RM! is operated five times and; magnet RM'Z four times making a total of nine steps taken by the repeater to select the ninth pin. For the digit 1 only a single ground pulse is sentv and line rela 223 alone transmits asingle pulse to magnet RMI. to step the repeater one step.

For the digit 2 only a single loo-p pulse is transmitted from the calling device and both line relays 223 and 23!] transmit a pulse to each of the magnets RM l and RM2 to cause the repeater to take two steps; The other digits are transmitted and registered in the repeater in a manner apparent from the foregoing description.

Returning now to the operation of the distributor 350 and finder 343 and as a result of the operation of line relay 3H1, the finder wipers are operated in a vertical direction in the well-known manner until vertical wiper 344 encounters the vertical bank contact 334 marked by ground at contacts 313. As is well-known the finder wipers are. now rotated in this level in search of the marking potential applied through the winding of cut-ofi relay 32!! to bank contact 333. When finder test wiper 343 encounters this potential the switching relay (not shown) in the finder switches the line and test leads through to selector 3'60 and also completes the circuit for operating cut-off relay 323 from conductor 311, wiper 343, bank contact 333, contacts. 31! and through the winding of relay 320 to battery. Cut-01f relay 320 at contacts 3' disconnects line relay 310 and at contacts 323 completes a locking circuit for itself independent of contacts 3!! from grounded conductor 311. Line relay 3!!) deenergizes and at contacts 3i i opens the original energizing circuit of. relay 326 which is now locked up through its own contacts. At contacts 3I3 relay 3!!) disconnects the marking ground from vertical bank contact 334 andv start ground from the distributor 358. At front. contacts 3L2 relay 3lEl' disconnect's. direct groundfrom conductor 302 and: the test conductor of the connector multiples but2atthe back contacts of armature 3I 2 relay 3! 0- sub-- stitutes ground extending by way of conductor: 311, wiper 343, bank contact 333, contacts 323,. and back contact 3l2 for maintaining conductor 302- and the test conductor of the connector multiples grounded thereby maintaining this linebusy to the connectors.

When the finder switches through to the selector a circuit is completed for energizing line relay 310 as follows: from ground at contacts. 242, contacts 223', right hand windings of're peating coil RC and resistance R2, front contacts: 23 i conductor 33E), finder bank contact 331, finder line wiper 34!, through contacts of the switching; relay (not shown) in the finder and the upper:

'winding of line relay 31 E] to battery. Line relaytlc energizes and operates the slow-to-release-re-- lay (not shown) in the selector to cause the latter relay to ground conductor 315 in the customary" manner.

As soon as thefinder finds the calling linean'd: switches through to the selector a circuit is com-- pleted for operating relay 240 which initiates the retransmission of the digits registered in the repeater. Retransmission of thefirst digit may take place after thefinder switches through while. the repeater is still receiving subsequent digits from the calling device. The circuit for ener gizing relay 24c may be traced as follows: from ground through the lower winding of selector line relay 3'58, over the selector and finder line conductors to finder line wiper- 34-2, bank contact. 332, conductor 33!, front. contacts 262, contacts 2'43 and through the lower winding of relay 240: to battery. At contacts 244 and 245 relay 240 completes a locking circuit for its lower winding. from grounded conductor 332 and opens its original energizing circuit at contacts 246.

At contacts 2:31 and 243- completes a loop cir-- cuit as well as thepulsing circuit for selector line relay 319 in place of its origina energizing cuit from contacts 242. This circuit extends'from' ground through the lower winding of line relay 313, wiper 342, bank contacts 332, line conductor 331 front contacts 262, contacts 2M and 243, im-- pulsing contacts 223, right-hand windings of re;- peat coil RC and resistance R2, front contacts 23!, line conductor 33!], bank contact 33l, wiper 34!, over the line conductors in the finder and selector through the upper winding of line: relay 310- to battery. At contacts 241 relay 240 completes a circuit for relay 233 which is the first" relay of a chain of three relays for controlling the transmission of outgoing pulses from the repeater. The circuit for energizing relay 233 may be traced as follows: from ground at contacts 223, contacts 241 and 253, conductor 308 through the frame of the repeater to stop contacts I91 and I98, repeater cam contacts I93. and I94, spring wiper contact I92, conducting ring I95, conductor 309, contacts 221. and through the winding of'relay 233 to battery.

Relay 233, upon energizing, at contacts232 completes an obvious circuit for energizing relay 228 and at contacts 234 completes a locking circuit for itself through contacts 221. At contacts 235 relay 233 completes an obvious circuit for slow-to-release relay 231 and also completes a circuit over conductor 3% for energizing sending magnet SM. Relay 231 at front contacts 238 'completes a circuit for energizing slow-to-release relay 224 and at contacts. 233- maintains conductor 3%. grounded after energization ofrelay 224. Relay 223 at contacts 229 completes an obvious circuit for energizing pulsing relay 225. Relay 224 at contacts 255 prepares a point in the circuit for pin restoring magnet PRM and at contacts 222 connects the Send Tone source through condenser CI to the upper talking conductor for the purpose of advising the calling subscriber that the repeater is transmitting the registered digits. The disconnection of ground at contacts 223 is Without effect because ground at contacts 236 has been substituted therefore.

Pulsing relay 225, upon energizing, at pulsing contacts 226 opens the previously traced loop circuit extending to selector line relay 316 to deenergize line relay 310 for the first pulse. At contacts 227 relay 225 opens the circuit for relay 233 whereupon relay 233 deenergizes to open the circuit of relay 228 at contacts 232 and to open the circuit of relay 231 and sending magnet SM. Relay 231, due to its slow-to-release characteristics, maintains its armature attracted during the retransmission of a series of pulses comprising a digit. Sending magnet SM deenergiz-es and steps the pin restoring arm I90 of the sending member one step over the next adjacent pin H39. Relay 228, upon deenergizing, at contacts 229 opens the circuit of pulsing relay 225 which closes the loop circuit to selector relay 3'"! at contacts 226 and which closes the original energizing circuit of relay 233 at contacts 22?. Relay 233 again operates thereby again operating relay 228 and sending magnet SM as well as recompleting the circuit for relay 231 before it is restored. Relay 228 again operates pulsing relay 225 which again opens the loop circuit to line relay 313 to transmit another pulse at contacts 223 and again opens the circuit to relay 233 which deenergizes. Relay 233 again releases and opens the circuits to relay 223 and sending magnet SM which operates restoring arm I99 of the sending member another step. Relays 225, 228 and 233 operate and release within predetermined times according to their characteristics to cause the relay 225 to transmit loop pulses in accordance with the standard time intervals normally required for the operation of the automatic switches. Relays 228, 225, 233 and sending magnet SM operate in this manner until sending magnet SM operates restoring arm I93 to the first displaced pin I30 corresponding to the first registered digit. When the displaced pin is reached repeater stop spring I9! is disengaged from spring I98 with the result that the circuit for relay 233 is not again completed during the transmission of impulses for this registered digit. The selector line relay 370 is deenergized for each pulse to step the selector Wipers in a vertical direction to select a group of trunks in the level corresponding to the retransmitted digit in the well-known manner. Shortly after stop springs I97 and I38 are opened by the 1st displaced pin relay 237 deenergizes since the circuit to relay 233 was opened by the stop springs. At contacts 236 relay 231 disconnects ground from conductor 338, at front contact 2% opens the circuit to slow-to-release relay'224 which maintains its armature operated for a short period thereafter and at back contacts 238 momentarily completes a circuit through contacts 255 and over conductor 33'! for the pin restoring magnet PRM.

Pin restoring magnet PRM is momentarily operated to operate its armature I25 and pin restoring rod I19 thereby pivotally operating. pin restoring arm I 93 to restore the displacedpin to its normal position. Shortly thereafter slowto-release relay 224 deenergizcs and at contacts 255 opens the circuit of pin restoring magnet PRM which restores its armature I25. The pin restoring rod [19 and pin restoring arm I are thereby restored to normal and stop springs I91 and I98 are permitted to 'close. The selector 360 is automatically operated in its rotary movement to select an idle trunk in the selected level during the release time of relays 23'! and 224. When relay 224 closes contacts 223 the original circuit previously traced for relay 233 is again closed to energize relay 233. Relays 225, 228, 233, 231 and 223 operate in the same manner as previously described, relay 225 to transmit loop pulses at contacts 226 to operate subsequent automatic switches, relay 233 to transmit pulses to operate sending magnet SM until stop springs I9! and I98 are opened by the second displaced pin and re-. lays 231 and 223 to control the operation and release of pin restoring magnet PRM as well as reinitiating the reenergization of relay 233 for a subsequent digit. In the same manner as just described, all of the registered digits, as determined by the displaced pins are retransmitted to operate the automatic switches to complete the connection to the called line. When the last .pulse of the last registered digit is transmitted spring I94 engages cam I'II to separate springs I93 and I94 thereby preventing reenergization of relay 233. Springs I93 and I94 remain open until the pin selecting member and cam I'II are roe tated on a subsequent call. Shortly after the last retransmitted digit sending tone is disconnected from the upper talking conductor thereby informing the calling subscriber that the repeater has completed retransmission of. the digits.

When the called subscriber answers the talk ing circuit is completedoverthe talking circuit comprising the heavy talking conductors and repeating coil RC, the called subscriber being fed talking battery from the battery feed relay in the connector in the usual manner while the'calling subscriber is fed talking battery. through the windings of line relays 220 and 230.

After conversation and in response to the replacement of the handsets at both calling and called substations the apparatus-and switch train is released. In response to the replacement of the handset at the calling substation line relays 220 and 230 deenergize andthe latter relayat front contacts 23I opens the circuit of release re-. lay253. Atback contacts 23I and 221I relays 29!] and 295 again energize but the energization of these relays is without efiect this time since the line relays are not reenergized as during pulsing. Relay 260 deenergizes after an interval and at contacts 263 and 265 open the locking cire cuitsof relays 290and 295 which deenergize. At contacts 268 re1ay;260 grounds conductor 308 to automatically restore or spill out, any registered digits in the repeater in case a subscriber initiates and only partly registers some of the calling partys digits and then abandons the call. At contacts 26I and 262 relay 260 opens theloop circuit across conductors 300 and Bill to release the automatic switch train in the. usual manner if not already released. I

In response to the'replacement of the handset on the cradle at either the calling or called party's desk set ground is removed from the control conductor 375 in the usual well-known manner. In response to this removal of ground, cut-01f relay 320 and relay 240 deenergize. All of the apparatus is now returned to normal and maybe used on subsequent calls.

In case the calling subscriber should abandon-a call after one or more digits have been registered in the repeater the line relays 220 and 230 and the release relay 260 deenergize in the same manner as previouslydescribed. At contacts 2B] and 282 the loop circuit to the automatic switch train is opened to release the switch train and the circuit to relay 240 is opened to cause the latter relay to release. At contacts 26 8relay 251] grounds conductor 388 to cause the operation of relay 23.3 and the transmission of the registered digits stored in the repeater. The circuit for operating relay 233 extends from ground by way of contacts 268, conductor 3 08, through the frame of the repeater to the pin restoring arm I90, through stop springs I91 and I38, cam springs I93 and I94, wiper contact I92 and conducting ring 195, conductor 309, contacts 221 and through the winding of relay 233 to battery. scribed relay 233 operates relay 228, relay 231 and sending magnet SM. Relay 228 operates relay 225 which releases relay 233. Relay 225 opcrates its contacts 226 as before but since the loop circuit is opened at contacts 26I and 262 theoperation of contacts 226 is without effect and the storedimpulses may be spilled out withoutoperating any switches. Stop springs I91 and |38 are-controlled by the displaced pins corresponding to the stored digits to control the operation of relays 233, 2 31 and 224 and pin ree storing magnet PRM in the same manner as previously described to restore all of the displaced pins. At the time the last pin is restored cam I'll opens cam springs !93 and I94 tostop further operationsfof relay 233. The repeater is n resto-lodmto normal andniay be used on sub-.- equentcalljs.

," Incorning calls arev completed. by way of the conn cto multiples o'nn; M w n nector'inotsho'wn) engages these bank contacts. h autbrn i conn ctor n the W own ma ner grounds conductor 301M181 the test bank 9mm o ergi e n c trofi e ay 3.29- At contacts-3y relay 32p disconnects line relay 3H] from conductor 3110. The connector then canj s rin in ner to he g e 7 1 1 0 1: ductor to energize ring r'elay 2|!) by way of ontacts 26'! and condenser C2. Each time ring r ay Zllinergizes in response to ringing current staid" relay at baclrcontactsfll and 2 12 dis nnects the subscribers linefrom the repeati7 R an i i ifi "4 and 2 3 and t frontfcontacts 2| l and 2l2 completes the ringing circuit byway of conductor 21B, ringer R,,.

cradle springs 2 I 1, condenser C and conductor 2L9 for signalling the called subscriber. When the called"subscriber answers by removing the handsef'from' its cradle a direct current bridge, including cradle springs 2| 5, is closed across conduct0rs'"300 and130l to stop further applications ofri'nging' current in the well-known manner. At contacts 2l3 -rla y completes an obvious circuit forenergizing relay 2-50 which at contacts 252 locks itself to grounded conductor 302} At contacts 251 relay25ll. completes an energizing circuit through the upper winding of relay no there. byc'ausing'the energization of relay 242 which also locks to grounded conductor 392 at contacts :244and 245. At contacts 241 andf'243 relay 240 prepares a point in the talkingcircuit. '7

"After ithecalled subscriber has removed' his handsetand. when ring relay ZIO is deenergized line relays 220and 23U-areen'e'rgiz'ed over the subscribers loop. At front'c'onta'c'ts'23l the an In the same manner as previously decuit is completed for energizing release relay 2.30 which energizes and completes the talking circuit at front contacts 25! and 262. Although relays 290 and 295 energizeat this time, such energization is without effect for the reasons previously mentioned. Line relays 220 and 230-feed talking battery to the called subscriber while talking battery to the calling subscriber is fed. from the connector switch. The talk-ing circuit includes the heavy talking conductors, back contacts-2l l, 2&2, the windings of the repeat coil RC and front contacts 25! and 262.

After conversation and in response to thereplacement of the handset, line relays 220 and 2-30 and release relay 260 deenergize. At front contacts 26! and 262 the loop circuit to the connector switch is opened to permit the release of the connector. When the connector releases ground is removed from conductor 302120 release relays 249, 258 and 3281, The relays and; apparatus are now all restored to normal and'may 'be used on subsequent calls What is claimed is:

1. In an automatic telephone system, a subscribers line, impulse receiving and retransmitting means individual to said subscriber's line and operative in response to a plurality of series of impulses transmitted thereto by the calling subscriber to store said plurality of series or impulses, a plurality oifinders having access to said line, means responsive to the initiation of a call on said line for initiating, the operation of one of said finders to hunt for the calling line, a selector switch associated with said one finder, means responsive to said one f nder finding the calling line forconnecting the calling line tosaid selector switch in readiness to receive impulses, and means for initiating the retransmission of said stored series of impulses over said last men: tioned connection in response to the condition:- ing of said selector switch to respond to said im-.- pulses.

2. In an automatic telephone system, asubscribers line, impulse receiving and retransmit ting meansindividual to said subscribers line and operative in response to a plurality of series of impulses transmitted thereto bythe callin sub:

scriber to store said plurality of series of impulses, a plurality of finders havingaccess tosaid line, means responsive to theiniti ation of a call on Said l f r n t at h rreration of one of said finders to hunt for thecalling line, ase lector switch associated with said one. finde1;; means responsive to said one finder finding the calling line for connecting the calling linetogsaid selector switch in readiness to receiveimm lses, means for initiating the. retransmission oi 5 id stored series of impulses over said last rne'ntf ned connection in response to the conditionlngjf said selector switch to respond .to said impulses, and means for transmitting a sending tonetothe calling subscriber during the retransmission of said stored pulses.

3. In an automatic telephone system, a sub scribers line, a pushf-buttonlcalling devieeTi flia viduall to said line and operativefto .transrnit digits comprising coded pulses. circuit translating means individual to said line operated in response to the receipt of said coded. pulses for ,translat ing said coded pulses, into ground-pulses correspc-nding to the transmitted digitSQimpulsere-B ceiving and retransmitting means operated response to said. translated gr ound pul V storing saidtransmitted digits, ai pluirgiigy. g

finders having access to said line, means respon.

sive to the initiation of a call on said line for initiating the operation of one of said finders to hunt for the calling line, a selector switch associated with said one finder, means responsive to said one finder finding the calling line for connecting the calling line to said selector switch in readiness to receive impulses, and means for initiating the retransmission of said stored digits over said last mentioned connection in response to the conditioning of said selector to respond to impulse transmission.

4. In an automatic telephone system, a calling device for transmitting coded digits comprising one or a plurality of loop pulses and a ground pulse corresponding to certain digits, a pair of line relays both operated in response to each transmitted loop pulse and only one of said relays operated in response to each transmitted ground pulse, circuit means controlled by each of said line relays for translating said coded digits comprising 100p and ground pulses into pulses corresponding in number to the actual value of the transmitted digit, and an impulse receiving and retransmitting means operated in response to said translated digits for storing said translated digits.

5. In an automatic telephone system, a calling device for transmitting coded digits comprising one or a plurality of loop pulses, the number of loop pulses in a coded digit being equal to onehalf the value of the digit transmitted, a pair of line relays both operated in response to each transmitted loop pulse, circuit means controlled by the operations of said line relays for translating each loop pulse into a plurality of pulses thereby translating the coded digits into pulses corresponding in number to the actual value of the transmitted digit, and an impulse receiving means operated by said translated pulses;

6. In an automatic telephone system, means for transmitting loop pulses, a pair ofline relays both operated in response to each transmitted loop pulse, circuit means controlled by the operations of said line relays for translating each loop pulse into a plurality of pulses, and an impulse receiving means operated by each of said plurality of translated pulses.

7. In an automatic telephone system, means for transmitting loop pulses, a pair of line relays both operated in response to each transmitted loop pulse, circuit means controlled by the operations of said line relays for translating each loop pulse into a plurality of pulses, an impulse receiving means having a plurality of stepping magnets, and means for simultaneously operating said plurality of stepping magnets in response to each said translated plurality of pulses to step said impulse receiving means a plurality of steps to make a selection.

8. In an automatic telephone system, means for transmitting loop pulses, a pair of line relays both operated in response to each transmitted loop pulse, circuit means controlled by the operations of said line relays for translating each loop pulse into a plurality of pulses, an impulse receiving means having a' plurality of stepping magnets, a selecting device in said impulse receiving means, means for simultaneously operating said plurality of stepping magnets in response to each said translated plurality of pulses, and. a differential gear mechanism operated by the simultaneous operation of said stepping magnets for operating said selecting device a plurality of steps to make a selection in accordance with the number of translated pulses received.

9. In a telephone system, a callingdevice'for transmitting pulses in accordance with the digits in a called number, an impulse receiving and retransmitting device including a selecting arm operated step by step in response to the incoming pulses transmitted from said calling device to make selections in certain positions in accordance with the transmitted digits, 9, sending arm in said device normally having the same relative position as said selecting arm and adapted to follow said selecting arm, a stepping magnet for operating said sending arm over the same path as said selecting arm, circuit means including a plurality of relays for controlling the transmission of outgoing pulses and for correspondingly operating said stepping magnet to operate said sending arm step by step to the positions selected by said selecting arm, a circuit controlled by said sending arm at each said selected position for controlling said circuit means and relays to divide said outgoing pulses into groups corresponding to the digits transmitted from said calling device, an automatic switch train, and means for delaying the operation of said circuit means and said relays until such time as said automatic switch train is ready to respond to said outgoing pulses.

10. In a telephone, a subscribers line, a pair of line relays terminating said subscribers line; acalling device at the subscribers substation for transmitting impulses comprising a pair of interrupter springs, a make-beiore-break spring for controlling said interrupter springs, a pair of grounding springs, and a pair of normally open springs closed only during the transmission of the last impulse of each series, a loop pulsing circuit including both said line relays, said interrupter springs and both conductors of said line in series; a grounded pulsing circuit including said pair of grounding springs, said pair of normally open springs, said make-before-break spring and one of said interrupter springs, one of the line con ductors of said line, and one of said line relays in series; and subscriber controlled means for operating said calling device to transmit loop and ground impulses over said impulsing circuits to operate said line relays whereby both said line relays deenergize for each loop impulse and said one line relay is maintained energized over said grounded pulsing circuit while the other line relay deenergizes during each ground impulse.

11. In a telephone system, a subscriber's line, a pair of line relays terminating said line, subscriber controlled means for operating said line relays in response to the initiation of an outgoing call and in response to answering an incoming call and for restoring said line relays in response the subscriber disconnecting from such calls, subscriber controlled means for restoring and reoperating said line relays by transmitting impulses thereto, pulsing relays, means controlled by the restorations and reoperations of said line relays during impulse transmission for operating said pulsing relays to transmit outgoing impulses, and means including said last means for preventing the operation of said pulsing relays during the. operations and restorations of said line relays for initiating outgoing calls, for answering incoming calls and for disconnecting from such calls.

12. In a telephone system, a subscribers line, a pair of line relays terminating said line, subscriber controlled means for operating said line relays in response to the initiation of an outgoing call and in response to answering an incoming call and for restoring said line relays in response to the subscriber disconnecting from such aersmoo calls, animpulsecalling device on said subscribersline for transmitting loop :andgroundpul'ses over said line to restore andreoperate said line relays a plurality of times dependent'upon the number of loop and ground pulses transmitted,

a pair of pulse repeating relays for transmitting outgoing"impulses, means controlled by the restorations and reoperations of said line relays during loop impulsing for operating both said pulsing relays to transmit a pair of outgoing impulses for each loop pulse and during ground impulsing for operating only one of said pulsing relays to transmit a single outgoing pulsefor each ground pulse, and means including said last means for preventing operations of said pulse repeating relays during the operations andrestorations of said line relays for initiating outgoing calls, for answering incoming calls and for disconnecting for such calls.

13. In a telephone system, a subscribers line,

a; pair of line relays terminating said line, an impulse calling device on said line for transmitting operations of each of said pulse repeating relays, contacts on said one of said line relays for controlling one of said separate circuits, and contacts on the other of said line relays for controlling the other of said separate circuits.

14. In a telephone system, a subscrib'ers line, a pair of line relays terminating said line, an impulse calling device on said line for transmitting" loop and ground pulses over said line to operate said line relays, both said lines being operated inresponse to each loop pulse and only one of said line relays being operated in response to each ground pulse, a pair of pulse repeating relays operative for transmitting outgoing impulses, a separate circuit for controlling. the operations of each of said pulse repeating relays,

contacts on said one of said line relays for controlling one of said separate circuits, contacts on the other of said line relaysrfor controlling the other of said separate circuits, and'an impulsereceiving and registering device controlledby the transmission of said outgoing impulses in response to the operations of pulserepeating relays.

15. In a telephone system, a subscribers line, a calling device on said subscribers line for transmitting both loop and ground pulses correspond- 'ing. to the digitsin a called number inresponse' to the subscriber initiating a call, an impulse re.- ceiving and registering deviceinidividual to said :subscribens line operated in responseto said loop and ground pulses of said-transmitted digits for registering said digits, automatic switches,means including said receiving and registering device for retrans'mitting said registered digits as loop impulses only to-operate said automatic switches to complete the desired connection in accordance Withjsaid registered digits, and means operative theevent the-calling subscriber abandons the call for: operating said receiving. and registering device to eras said registrations without operating any of said automatic switches.

JOHN H. VOSS. AMANDA OBERGFELL; Execut'rz'x of the Estate of Herbert F. Obergfell,

deceased.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Blessing Dec. 19, 1916 Cesareo Apr. 1, 1941 Shephard Nov. 10, 1942 Dimond Dec. 1, 1942 Ostline -n Mar. 30, 1943 Carpenter -1 Apr.- 1 2, 1 932 'Saville Apr. 18, 1939 Number

Images