Patent GB-325019-A (GB)
Title: Improvements in or relating to telephone systems
IPC: H04Q3/42
Filed: 1928-11-13
Abstract: 325,019. Automatic Telephone Manufacturing Co., Ltd., and Ostline, J. E. Nov. 13, 1928. Addition to 265,653. Automatic exchange systems.-In a register translator system in which A and BC switches pick out a translator individual to the exchange required, the translated code is returned to set storage relays in the register controller, each digit being transmitted instantaneously by the connection of potential to one or more of a series of leads. Immediately the translated code is stored, the A and BC switches and the translator, which are common to several register controllers, are freed for use on other calls. The numerical digits are stored on registers in the controller, the register storing the last digit being used to distribute the preceding digits to their respective registers. Transmission takes place in the usual way facilities being provided to transmit the number in coded pulses if the connection is to be extended over a direct junction to a manual exchange fitted with coder call indicator equipment. General operation. A first code selector, Fig. 1, is connected by a switch DFS to a register controller, Figs. 2, 4, 6, 7 and 8, which is connected by switch ADF to an "A" digit switch, Fig. 5. This is raised by the first digit and hunts for a " BC " switch BCR, Fig. 3, which is set by the next two digits to a translator TRNS individual to the wanted exchange. Relays TC-TR are then energized in turn to send back the code digits as combination markings over a group of four wires to storage groups, Fig. 7, (3 groups M, N, R, out of 6, shown). The sending switch SS, Figs. 6 and 7, then transmits digits first under control of the storage groups, Fig. 7, and then under control of the numerical registers NS1 - - NS4, these controls being brought into action in turn by the switch CS. If the wanted exchange is manual, the relay TC, Fig. 3, records the fact on the storage system, Fig. 7, with the result that the numerical registers send code impulses (+ or -, weak or strong) from additional banks. Seizure of register controller and A-digit switch. Relays L, B, A, C pull up and ground is extended from 18 over wiper 31 of switch DFS in its normal position to stepping magnet 38, which continues to receive driving current over wiper 31 until the switch DFS finds an idle controller, whereupon K, F, Fig. 1, and A1, B1, BA, Fig. 2, pull up and a circuit is closed for relay S, Fig. 5, which pulls up its armatures (70 before 71) to start the switch ADF. When this switch finds an idle A-digit switch, K1 pulls up and energizes B2 and dial tone is returned from 81. Reception of impulses. The switch ADR responds to the first impulse train and hunts over the level dialled for a free outlet when H2 pulls up coupling ADR and ADF. Relay C1 (operated in series with magnet 93 of ADR) falls back at the end of the train breaking the circuit of magnet 151, Fig. 6, to move NS4 one step to prepare the apparatus to receive the next digit which raises BCR to the level required. Switch NS4 is moved on one step as before and the next digit enables magnet 164 to move the wipers of BCR in a rotary direction connecting them to the translator TRNS individual to the exchange required and when C3 (operated in series with 164) releases TA and HI operate in series. The conductors are extended to TRNS and the impulsing circuit is broken at 154. The next digit dialled is passed over the fourth bank contact of NS4 to the magnet NS1 which switch steps to set its wipers in accordance with the digit dialled. Registers NS2 and NS3 store the next two digits and the last digit is stored by NS4 which has been used previously to distribute the incoming digits. Translation and storing of translated code; release of A and BC switches and of translator. When relay TA pulled up in series with HI circuits were completed for 177, TB and TC. Relay 177 attracts the impulsing pendulum 181, TB extends holding earth to the translating relays TM, TR, and opens the circuit of TA releasing the pendulum which energizes PU at each swing. At the first energization of PU earth at 190 enables TM to attract its light armature 192 whilst earth at 182 is extended to the translating frame 175. If the call is to an automatic exchange SWA, Fig. 7, is operated completing at 401 a circuit to the driving magnet of CS which releases with SWA at the termination of the pulse to step the control switch CS one step. Relay TM energizes fully at the termination of the pulse locking 192 to 193 and breaking the circuit of TC. The next pulse is extended from earth at 190 to TN which operates its light armature 196 to operate fully when PU releases. The earth at 182 is connected to the common lead 194 over the cross connection field and for the translation shown, to relay MW of the first storage relay group and thence to SWA. MW locks to conductor 67. At the end of the pulse SWA releases and CS moves another step. The next pulse connects earth through the contacts of TN to the second group of storage relays NW, NZ, relays NW and NY being simultaneously operated with the translation shown. Relay SWA operates in series and as the pulse terminates CS moves on one step as before. The remainder of the translation is stored in a similar way except that relay SWB, which controls the sender start circuit, and not SWA pulls up in parallel with RW, RZ. The control switch magnet is operated by earth at 243 and relay ST pulls up its light armature to operate fully when PU and SWB release. Relay ST prepares at 245 a holding circuit to the operated storage relays and breaks the circuit of S which frees the switches ADR and BCR and the translator TRNS. Transmission of stored digits. When the wiper 248 of the switch CS moves into position 7 relay PR pulls up and transfers the control of the vibrator 252 to relay ST and the operation of this latter relay releases the pendulum to transmit the impulses required. Relay A, Fig. 1, responds to the impulses transmitted and repeats them to vertical magnet 135, Fig. 1, to raise FCR to the level required. The sender switch SS steps in synchronism with FCR. When the wiper 264 of SS reaches the second contact relay SA operates preparing a circuit for the stop relay SZ to pull up and completing at 267, a circuit for the driving magnet of Cb. The wiper 213 of SS moves over a bank marked in turn by the operated relays of the storage groups and for the first digit when a contact marked by relays MW, MZ is reached SZ operates locking the vibrator at 276, and completing a circuit to rotate the wipers of SS to their thirteenth position. In this position slow release relay SA relapses, opening the circuit of slow relay SZ. On the release of SA the control switch makes a step connecting the earth on 271 to the second group of storage relays. The subsequent digits are transmitted in a similar way. Returning now to the switch FCR, on the termination of the digit train relay E and magnet 138 interact to rotate the shaft until a free outlet is reached when relay H operates extending the pulsing loop to the switch ahead. To ensure that the numerical digits are not clipped in re-transmission the fourteenth contact of the bank of CS wiped by 248 is wired to the bank of NS2 wiped by 303 and consequently if 303 is not off normal when 248 connects to 404, PR will release holding 250 and preventing the sending pendulum from functioning. When 303 moves off normal a circuit for PR is completed releasing 250 and allowing SS to function as before. Similarly, the second digit is hld up until the third digit switch has moved off normal. When the final digit has been transmitted CS moves to its eighteenth contact opening the holding circuit of PR which releases to lock the vibrator 250. A circuit is also completed for MD, Fig. 1, which opens the holding circuit of K at 61. Relay K releases, switching through the speaking circuit at 23 and 21, breaking the circuit of A to release the register translator, and returning ringing tone to the calling subscriber from 305. When the called party replies D operates, releasing MD and metering the call over 308. Call to CCI Office. If the call is to a manual exchange the first strappings on the frame 175 complete a circuit from 182 to MI and SWA. MI completes at 313 an arc commoning circuit over the bank wiped by 264 of SS so that this switch will rotate over the whole of its bank at one operation. The switches NS1 - - NS4, in addition to storing the numerical digits on the banks wiped by 297 - - 294, store an equivalent code translation on banks 314 - - 316, &c. After the sending of the office code translation the switch CS will move to its 14th bank contact as before whereupon wiper 271 will complete the circuit for CR connecting the loop circuit at 255, 259 to the wipers 333 and 336 of the sender switch, preparing at 318 a stop circuit in the sender circuit and at 319 completing a circuit for LS to prepare the CCI equipment to receive the coded pulses. Relays LS, LD and SZ operate and the busy relay BB is maintained by 326 of CR. When the CCI equipment is ready to receive the pulses LS and LD release. LD breaks the circuit of SZ and if the whole of the numerical digits have been received the vibrator 250 is released to step the sender switch. If all the numerical digits have not been stored PR is free to hold the vibrator. When the fourth digit has been recorded CI which is held operated in series with NS4 completes a circuit for PR to release the vibrator. The switch SS moves round and its wipers 333, 336 send coded pulses to the CCI equipment as controlled by the setting of switches NS1 - - NS4, the number being transmitted in one revolution of SS. When SS reaches the seventeenth contact the stop on 407 placed by 318 of CR becomes effective completing the circuit of SZ as before to stop the vibrator and return the switch SS to normal. When SS reaches its home position the circuit of SA over 264 is broken an