Patent GB-197643-A (GB)
Abstract: 197,643. Automatic Telephone Manufacturing Co., Ltd., (Assignees of Willis, B. D.). May 10, 1922, [Convention date]. Addition to 163,807. Order apparatus.-In a call indicator for use in a semiautomatic telephone system the wanted numbers are recorded on register sets, such as the register set R', R<2>, Fig. 4, each digit register R<1> or R<2> comprising a group of relays, a particular relay or combination of relays of each group in succession being energized by a step-by-step controlling switch RCS, Fig. 3, which responds successively to each digit dialled. The numbers stored in the register sets are transferred in rotation to the lamp indicator by a transfer switch CCS, Fig. 2. Setting of digit registers by dialling impulses. The series of impulses sent by the calling subscriber deenergize the line relay 204, which completes an impulse circuit 218, 233, 307 for the stepping magnet 359 of the register controlling switch RCS. The wiper 355 of this switch engages two) rows, of contacts which are appropriately connected to four conductors normally extending over the resting contacts of a switching relay 400 to four selecting relays 402, 401 &c. of the first digit register R<1>.. The setting of the switch RCS prepares a circuit for one or more of these selecting relays, according to the digit dialled, which circuit is completed over the armature 326 and relay 308 when the slow-release series relay 307 falls back on the cessation of an impulse train. The selecting relay or relays, energized over the wiper 355, lock up over a circuit including their upper armatures, the switching relay 400 and the grounded conductor 404, whilst their lower armatures prepare a circuit for the appropriate one of a bank of indicator lamps. Each bank of ten lamps is wired in multiple to the appropriate contacts of all the corresponding registers at the operator's position. The response of relay 308, on the cessation of the impulses, completes a circuit for the relay 309 which locks up, energizes the release magnet 358 to restore the switch RCS to normal, and breaks the circuit of the relay 308. The switching relay 400 energize.s and extends the four conductors from the switch RCS to the selecting relays 410 &c. of the next digit register R<2>. The next series of impulses operate the controlling switch RCS which energizes a particular relay or combination of relays in the second digit register R<2> thereby preparing the circuit of the appropriate lamp in the second bank of the indicator. The switch RCS is released as before and the switching relay 405 may extend the control to further digit registers which are operated in like manner, but in the present arrangement the register set R<2> is the final one and the relay 405 completes. a circuit for a relay 305 over conductors 404, 414. Transfer of wanted number to the lamp indicator by the transfer switch CCS, Fig. 2. Relay 305 locks up over its armature 361 and completes a circuit for a relay 262 of a rotary switch CCS, the bank contacts of which are connected to conductors 271 - - 276 associated with all the register sets at the position. Relay 262 closes a circuit for the slow-release relay 261, and the wiper 264 is connected to a point between the stepping magnet 263 and the switching relay 260. The bank contacts are normally grounded at the registers, but when a register is ready to transfer a number, ground is removed from the corresponding bank contacts at armature 365 of relay 305. If the wiper 264 ,rests on a grounded contact it is rotated after the manner of a line switch until an un. grounded contact is reached, when the switching relay 260 is energized and rotation is arrested. Assuming this is a contact connected to conductor 271 associated with the register set under consideration, on the response of the switching relay 260, the circuit of relay 261 is broken, but before this relay relapses, the transfer relay 304, Fig. 3, of the register set is energized in a circuit 268, 270, 266, 264, 271, 365, and locks up over grounded conductor 404. The relay 304 (1) grounds the conductor 490 at armature 391, thereby completing the circuits of the selected lamps in the digit t registers R', R<2>, and (2) connects the grounded lead 404 to the test conductor 271 to hold relay 260 energized and the switch CCS stationary until the call is disposed of.