Patent GB-218287-A (GB)
Title: Improvements in or relating to automatic or semi-automatic telephone systems
IPC: H04Q3/00
Filed: 1924-06-23
Abstract: 218,287. Automatic Telephone Manufacturing Co., Ltd., (Assignees of Richardson, R. G.). June 25, 1923, [Convention date]. Automatic exchange systems.-A register-controller of the kind which translates the first portion of the designation of a wanted subscriber's line into a routing number, is adapted also to translate the entire designation from one numerical base to another. The invention is described with reference to a network of 160,000 lines divided into 16 offices of 10,000 lines, the offices being given the distinguishing numbers 1 to 4, 6 to 9, 11 to 14, and 16 to 19. The subscribers' designations are listed according to a system of notation employing the numerical base of twenty. and the impulse senders are of any suitable known kind adapted to generate up to twenty impulses. Four characters only are therefore necessary for listing the lines of the entire network, the impulses corresponding to these four characters being registered on four twenty-point register switches of a register-controller and translated into one or two office-routing numbers and four numerical digits, in decimal notation. Although for convenience of description each of the characters is imagined to consist of one of the numbers from 1 to 20, in practice, the numbers 1 to 9 and 0 may be used for the first ten symbols of each character, and the first ten letters of the alphabet omitting the letter I (which is apt to be confused with the number 1) may be used for the second ten symbols. Fig. 1 shows the manner in which the listing numbers are allocated to the sixteen offices. All the numbers beginning with 1, i.e. 8000 numbers, are assigned to Office No. 1. all those beginning with 2 to Office No. 2, and so on, the remaining numbers beginning with 5, 10, 15, and 20 being divided into quarter-blocks of 2000 numbers, one of which is allotted to each office to bring its capacity up to 10,000. To accord with the capacity of the standard 100-point switches which are used in setting up the connections, the 10,000 lines of each office are divided into ten onethousand line groups which are sub-divided into ten one-hundred line groups, each of which is served by a group of connectors. In Office No. 1, the block of 400 lines whose listed designations begin with the two characters 1-1 are allotted to the first four connector groups of the first thousand group, the 400-line block whose designations begin with the two characters 1-2 to the second four connector groups in the first thousand group, the 400-line block beginning with the characters 1-3 to the first four connector groups in the second thousand group, and the 400-line block beginning with the characters 1-4 to the second four connector groups in the second thousand group, while the 400-line block beginning with the characters 1-5 is assigned to the ninth and tenth connector groups in the first and second thousand groups. This scheme is continued throughout the number lay-out of Office No. 1, the 2000 lines beginning with the character 5 being assigned to the ninth and tenth thousands groups. The other offices are similarly arranged. The one hundred lines of each connector group are assigned in their numerical order in the connector 'banks. A calling subscriber's line is extended over a line switch C, Fig. 4, and a forwardly-hunting switch SS associated with the first selector trunk, to an idle register-controller, the general arrangement of which is similar to the register-controller described in Specification 200,484, but the register switches of which are provided with two or more wipers. The wipers of each register switch are connected to the contact banks of the wipers of the other register switches in such a manner as to bring about the necessary translation. Means are also provided in the register-controllers for signalling an attendant and giving the calling subscriber a busy signal if the sending switch SEN, Fig. 6, fails to find a contact grounded over one of the stopping wires 1 to 9 and 0. Seizure of an idle register-controller. The non- numerical switches C, SS, Fig. 4, operate in the usual way. On the response of the switching relay 86, the register-controller release relay 201, Fig. 6, is energized, and a bridge is placed across the selector trunk 30, 32 to prepare the first selector D for operation in well-known manner. Setting of register-controller. The wanted subscriber's designation is now dialled, the impulse series being repeated by the relay 75, Fig. 4, to the magnets 301, 304, 401, 404 of the register switches R1 - - R4, Figs. 7 and 8, these magnets being brought into impulse circuit in turn by a switch S, Fig. 5, which is advanced a step at the termination of each impulse series by the relapse of a slow-release series relay 101. Transmission of control impulses by registercontroller. At the termination of the dialling of the second impulse series, the wiper 108 of the switch S, Fig. 5, connects the grounded wire 141 to a starting circuit 139, in which an impulsesending relay 202, Fig. 6, is intermittently energized over an interrupter 221. On the first response of the relay 202, the stepping magnet 222 of the sending switch SEN is energized, and on the next de-energization of the relay 202 advances its wipers to their first position, in which a circuit is completed for the pick-up relay 203, which at armature 213 energizes the stepping magnet 131 of the sequence switch S', Fig. 5. The relay 203 also at armature 212 opens a shunt across the impulsing armature 210, so that on the next response of relay 202 an interruption is produced in the outgoing control circuit. Upon the next relapse of relay 202 the switch SEN is advanced another step. The numbered stop conductors leading from the bank contacts engaged by the sending switch wiper 224 are connected over a jumpering frame IDF, Fig. 10, to the contacts engaged by the wipers 312, 313 of the first register switch R1, Fig. 7, and are directly connected to the correspondingly numbered conductors leading from the banks of the other register switches R2, R3, R4. The sending switch SEN continues advancing as described above, until the wiper 224 engages the stop conductor, which is at this time grounded over a jumpering wire on the frame IDF, Fig. 10, the wiper 313 of the register switch R1, Fig. 7, and the wiper 135 of the sequence switch S', Fig. 5, in its first position. The stop relay 204, Fig. 6, is energized in this circuit, locks up, disconnects the impulse relay 202, deenergizes the magnet 131 of the sequence switch S<1> which advances to its second position, and closes a restoring circuit for the sending switch SEN. The relays 203, 204 relapse after an interval sufficient to permit a hunting operation to take place at the first selector D, and the relay 202 then again commences to vibrate. The impulse-sending operations are now repeated and the second office-routing number is sent out, the circuit for the stop relay 204 extending this time over a jumpering wire on the frame IDF, the wiper 312 of the first register switch R1, and the wiper 135 of the sequence switch S' in its second position. If only one office-routing digit is required to route the call to the wanted office, the conductor leading from the contact engaged by the wiper 312 of the first register switch R1, is jumpered across the frame IDF to an additional wire X, which is connected to the second contact engaged by the sequence switch wiper 133. When, therefore, the sequence switch S<1> arrives in its second position, after the first routing digit has been sent, its circuit is immediately closed again and it moves to its third position, in this manner skipping its second position in which the seoond routing digit is normally transmitted. The thousands, hundreds, tens, and units digits are similarly sent under the control of the register switches, in the third, fourth, fifth, and sixth positions respectively of the switch S<1>. Translation by register-controller. From an inspection of Fig. 1 it will be seen that when the first character in the listed designation is 5, 10, 15 or 20, the wanted office is jointly determined by the first two characters. Accordingly, the 5th, 10th, 15th and 20th contacts in the banks of the wipers 312, 313 of the first register R1, are not connected to the righthand side of the frame IDF as are the other contacts, but if this register is set to one of these positions, when the starting conductor 139, Fig. 5, is grounded, a circuit is completed over the wiper 313 of the register R1 and one of the conductors 371 - - 374 for one of four switching relays 301 - - 304, Fig. 9, which relay locks up and connects two sets of conductors 381 - - 384, 391 - - 394, coming from the banks of wipers 325, 326 of the register R2, to the four pairs of terminals on the right-hand side of the frame IDF corresponding to the four offices among which the 8,000 lines corresponding to the first character are distributed. The stopping circuits of the first and second office-routing digits are thereby extended over conductors 151, 152 and wipers 325, 326 of the register R2, to the appropriate pair of terminals of the selected set of four pairs on the frame IDF. The thousands group is determined by the first two listed characters excepting when the second character is 5, 10, 15 or 20, when it is determined by the first three characters. For example, if the first two characters are 5-5, the thousands stopping circuit extends over conductor 161, wiper 311 of the register R1, wiper 323 of the register R2, and wiper 414 of the register R3, and thence to a stop conductor 9 or 0. If, however, the second character is not a multiple of 5, the wiper 323 of the register R2, extends this circuit directly to a stop conductor 9 or 0. If the first character is not a multiple of 5, the thousands stopping circuit extends over wiper 311 of the register Rl and wiper 411 of the register