Patent GB-211662-A (GB)
Abstract: 211,662. Western Electric Co., Ltd., (Polinkowsky, L.). Jan. 15, 1923. Automatic exchange systems.-In a registercontroller system, if a group selector in its automatic hunting movement finds all the trunks busy, it advances to an overflow position, whereupon the switches are released and are again operated under the control of the register-controller. A call is extended over a call-finder and preliminary selector (Fig. 1) of the no-normal rotary type, a first group selector (Fig. 2) a second group selector (Fig. 4), and a connector (Fig. 5), all of the power-driven panel type, under control of a register-controller (Fig. 3) selected by a hunting switch 246-251 at the first group selector. The registers A-E are connected up in turn by switch F and set by means of the impulse relay 300. The bank terminals are connected to counting relays as required for the method of translation to be used. The selecting operations begin as soon as the registers A, B have been set. If all the trunks are found busy, a timing device 367-370 comes into action, allowing release of the selectors without disturbing the registers, and positioning the register-controller to initiate the selecting operations again. Means are provided for rendering the selectors non-selectable while they are released. Call finder and preliminary selector, Fig. 1. When the calling subscriber removes his receiver, line relay 102 energizes and applies a selectable potential to the test terminal 109. Relay 105 energizes and connects up the stepping magnet 115, relay 116 being shunted out. When the marked terminal is reached, relay 117 energizes over the test wiper and brings into circuit sluggish relay 116, which operates after an interval during which the test relay 119 energizes over its left winding and locks if the wipers 121- 124 are standing on a busy trunk. The stepping magnet 115 does not operate in series with relay 116, but the stepping magnet 120 now operates and drives the wipers until an idle trunk is found, when test relay 119 releases and opens the driving circuit. Relay 116 also closes a circuit for the out-off relay 103 through the meter magnet 113 and relay 117, releasing relays 102, 105. At the first group selector, to which connection is made over the trunk 125-128, relay 202 is energized over contact 203 and the test wiper 124, and drives sequence switch 210 into the 2nd position, in which relay 118 energizes over wiper 123 and contact 207, switching through the speaking leads, releasing relays 116, 117, and locking in series with the cut-off relay 103 over wiper 112. Setting of register-controller. The stepping magnet 209 of the auxiliary switch 246-251 operates over contact 224 to select an idle registercontroller, relay 202 remaining energized as long as the register-controllers engaged are busy over contacts 206, 208, wiper 246, terminal engaged thereby. multiple terminal at some other selector and relay corresponding to 211. When an idle register-controller is found, relay 202 relapses and moves switch 210 to the 3rd position, a circuit being momentarily closed over contacts 214, 208, wiper 246, contact 308 in series with relay 303 for relay 211, which locks to mark the register-controller busy, and connects the speaking leads to the impulse relay 300, which energizes and connects up slow release relay 301. Relay 303 drives sequence switch 310 to the 3rd position, in which dialling tone is sent over transformer 338, wiper 317 of register A in its normal position and contact 343. The first train of impulses is repeated over the back contact of relay 300 to the magnet 311 of register A over slow release relay 302 and wiper 334 of switch F in its 1st position. Relay 302 connects up the magnet 305 which advances switch F one step upon release of relay 302 at the end of the train, transferring the impulsing circuit to the next register B, and driving sequence switch 310 to the 4th position over wiper 337. Switch F moves into the third position at the end of the second train, and relay 307 is energized, moving the sequence switch to the 5th position in which the remaining registers C, D, E, are set. After the last train of impulses, the relapse of relay 302 moves switch F to the 1st position. Control of first group selector, Fig. 2. In the 5th position of sequence switch 310, that is, as soon as registers A, B have been set, the fundamental circuit is completed over relay 202, contact 213, wiper 249, contact 339, stepping relay 362, back contact of counting relay O<1> and contact 341. Relay 202 moves sequence switch 210 to the 4th position, in which the up-drive magnet 225 operates. As the wiper shaft is raised, brush 235 moves over commutator 229, intermittently connecting earth to relay 202 over contacts 206, 222 and shunting the stepping relay 362. Relay 362 upon energization closes a circuit over contact 343, wire 378, contact 344, wiper 319 of register A and selected terminal to a counting relay, such as 1, and the latter prepares a circuit for itself and relay 1<1> in series, which is completed at the first shunting of relay 362, relay 361 being energized over contacts 342, 304. The counting relays operate in pairs, until the fundamental circuit is opened upon energization of relay O<1>, which also moves sequence switch 310 to the 6th position, contact 342 being momentarily opened to release the counting relavs. The movement of the wiper shaft stops with the brush 235 on the next insulating segment of the commutator, and relay 202 falls back and advances sequence switch 210 to the 5th position, in which the selected wipers are tripped by magnet 277. The fundamental is again closed and sequence switch 210 moves into the 6th position, in which the up-drive magnet 225 operates to effect group selecting, relay 202 being intermittently earthed at commutator 230 to shunt the stepping relay 362, which completes a circuit over contacts 304, 344, wiper 318 of register A and a counting relay. The counting relays energize in pairs, finally opening the fundamental circuit and advancing sequence switch 310 to the 7th position. Relay 202 releases and moves sequence switch 210 to the 7th position in which it energizes again over contact 209, wiper 251 and contact 341 and advances the switch 210 to the 8th position, in which, if the first trunk of the group is busy, relay 202 is held over contacts 206, 222 and the test wiper 242, and the up-drive magnet 225 operates. Relay 202 is held over contact 203 and commutator 231 until the wipers 240-242 are accurately centred on the terminals of an idle trunk, and then releases, advancing sequence switch 210. Ground is applied to the test terminal 245 over brush 236, overflow commutator 232 and contact 222. In the 9th position of switch 210, relay 303 energizes over contact 339, wiper 249, contact 213 and commutator 232, locks and in the 10th position operates relay 202, bringing sequence switch 210 to rest. Sequence switch 310 moves into the 8th position, and relay 307 energizes over contact 345 and wiper 337 of switch F in 3rd, 4th or 5th position until registers C, D, E, are set, whereupon it releases and advances the sequence switch to the 9th position. Control of second group selector, Fig. 4. The fundamental circuit is closed over relay 403, contact 404, wire 401, contact 220, wiper 250, relay 362, contact 341, wiper 251, contact 219, wire 400, contact 411. Relay 403 moves sequence switch 410 to the 2nd position, in which the up-drive magnet 418 operates, relay 362 being shunted intermittently at commutator 421. Relay 406 energizes end locks over contact 407 and the test wire 402. Relay 362 upon energizing closes a circuit over contacts 343, 344, 351, wiper 321 of register B and selected counting relay, and the counting relays operate in pairs until relay O<1> opens the fundamental circuit, and advances sequence switch 310 to the 10th position. Relay 403 releases and moves sequence switch 410 to the 3rd position, in which the trip magnet 420 energizes. The fundamental circuit is again closed, and relay 403 advances switch 410 to the 4th position and the up-drive magnet 418 operates to effect group selecting, relay 362 being shunted intermittently at commutator 422. Relay 362 initially closes a circuit over contacts 304, 344, 351, wiper 320 of register B in 5th position say, contact 352, wiper 325 of register C and selected counting relay. Relay O<1> upon energizing advances sequence switch 310 to the 11th position, and relay 403 releases and moves sequence switch 410 to the 5th position. Relay 403 energizes again over contact 409 and ad. vances switch 410 to the 6th position, and remains energized if the first trunk is busy over contact 404 and the test wiper 429, and the updrive magnet 418 operates. Relay 403 relapses when the wipers 427-429 engage an idle trunk, and drives sequence switch 410 to the 7th position in which the test terminal 432 is earthed at contact 416, and relay 403 energizes over contacts 404, 414, wire 500 and contact 503 at the selected connector, and advances switch 410 to the 8th position. Control of connector, Fig. 5. The fundamental circuit is closed over relay 505, contacts 506, 507, 504, wire 501, contact 412, wire 401, and as before over stepping relay 362 and back by wire 400 and contact 411. Sequence switch advances to the 2nd position and the high-speed up-drive magnet 514 operates, relay 362 being shunted intermittently at commutator 519. Relay 362 initially closes a circuit over contacts 343, 344, 350, wiper 327 of register C and selected counting relay, and relay O<1> upon energizing moves sequence switch 310 into the 12th position. Relay 505 upon release advances sequence switch 510 to the 3rd position, in which the trip-magnet 517 is energized. The fundamental circuit is closed and the up-drive magnet 514 operates in the 4th position of switch 510, relay 362 being shunted intermittently at co