Patent GB-378762-A (GB)
Title: Improvements in or relating to electric signalling systems
IPC: H04Q9/00
Filed: 1932-01-06
Abstract: 378,762. Electric signalling systems. ASSOCIATED ELECTRIC LABORATORIES, Inc., 1033, West Van Buren Street, Chicago, U.S.A. Jan. 6, 1932, No. 441. Convention date, Feb. 20, 1931. [Class 40 (i).] In an electric signalling system in which devices to be operated are selected over selectors, two selectors are operated simultaneously to select two groups of devices and keys are provided to select the group and the device required without further setting of the selectors. Indicators are provided to indicate to the operator the positions to which the selectors have been set. The invention is described as applied to a mimic diagram system, the selectors each selecting groups of devices on the board, the individual devices being selected and operated by keys individual to the wipers of the selecting switches. Specification 371,844 is referred to. If it is desired to select the devices shown on Fig. 4, the key TK is operated and the number 1030 is dialled. The first two digits are repeated by relay 101 to magnets 135 and 136 respectively and the group selector GS is stepped to the 10th contact on level 1, connecting wipers 130 and 131 to the magnets of BS, wipers 132 and 133 to the magnets of AS and wipers 134 to cables 10 and 20 to illuminate lamps 1 and 0 in the first and second sections respectively of both panels ASP and BSP. The next digit, 3, is repeated by 101 to magnets 201, 253 of switches AS and BS respectively and these switches are stepped to their third levels whilst the final digit energizes magnets 202 and 254 and switches AS and BS are rotated so that their wipers engage the 10th contacts on the 3rd levels. The relay chain 102 .. 108, Fig. 2, provides the change-over between the digits whilst the earthing of 126 at the end of the third digit enables relays 210, 232 in the chains 208 .. 217 and 230 .. 239 to be energized from vertical wipers 267 and 268 respectively to illuminate lamps 3 in the third section of panels ASP, BSP. The lamps O in the final sections of the panels are illuminated from wipers 266 and 269. The panel ASP thus indicates that the wipers of the switches reached over contact 0 of level 1 of GS are standing on contact 0 of level 3 whilst BSP indicates the position of the wipers of the other selected switch. Wipers 261 .. 265 are thus connected directly to magnets 310 .. 314 which control the indicators on the section A, A whilst wipers 273 .. 276 are connected with magnets 335 .. 338. If key LK is thrown to the right AR energizes, lamp AL lights and the lamps on BSP are extinguished. The keys LD, OS, BP, BD and TD are then connected directly to the wipers of the switch designated on ASP and by operating the appropriate key the correct number of times any notching magnet can be operated so that its disc shews a required indication on the display board. If the key LK is moved to the left, the operating keys are connected to the wipers of BS, the lamps on indicator ASP are extinguished and magnets 335 .. 338 can be operated by means of the appropriate keys OS, BP, BD, TD. The release of TK earths the release conductor 11 and removes earth from hold conductor 12. Release magnets 137, 204 and 255 energize to allow switches GS, AS and BS respectively to restore and all energized relays are released.