Patent GB-361462-A (GB)
Title: Improvements relating to electric signalling systems
IPC: H04L12/18
Filed: 1930-09-08
Abstract: 361,462. Electric signalling systems. SIEMENS BROS. & CO., Ltd., Caxton House, Tothill Street, and BROOME, J. H., 64, Heathwood Gardens, Charlton, both in London. Sept. 8, 1930, No. 26771. [Class 40 (i).] In a signalling system for transferring to secondary apparatus indications registered on primary apparatus, wherein a set of primary apparatus is connected to a set of secondary apparatus over a common group of wires, a single assigner mechanism is associated in common with both sets whereby each primary apparatus and its corresponding secondary apparatus are assigned in turn for use of the common group of wires, and the operation of the assigner is suspended on the assignment of a primary apparatus on which registrations exist until such time as the transference of registrations to the corresponding secondary apparatus is completed. In the construction shown, the invention is applied to a totalizator system consisting of registers comprising counters, one for each denomination, and indicators, common groups of wires being employed between the registers and indicators for the several competitors. The wipers and banks of contacts ucr, tcr, ccr, mcr, tmcr, represent a register, the banks being provided, respectively, for the units, tens, hundreds, thousands, and tens of thousands digit places in which registration is required. Corresponding banks of the several competitor registers are multipled together by groups of ten wires extending to the banks of corresponding indicator control switches. Five indicator control switches IU, IT, IC, IM, TM, one for each digit place, correspond to the register shown. The driving magnets of these switches are energized respectively by the closure of contacts cudm, ctdm, cccdm, cmdm, ctmdm, which takes place when the respective portion of the indicator is moving to display a fresh digit. The movement of each indicator is by means of a clutch magnet such as CU. The assigner mechanism ASR comprises a rotary switch with wipers and banks of contacts as1 to as8. To operate the system, start key ST is closed to complete a circuit through relay CL which at contacts cl1 to cl5 connects positive to the wipers ucr to tmcr in the first register associated with the assigner switch. If this register is in the normal position, as shown, then circuits are completed for relays UC to TMC which at contacts uc1 to tmc1 ensure that circuits for clutch magnets CU to CTM are open and at contacts uc2 to tmc2 complete a circuit for relay S. This relay at contact s1 closes a circuit for magnet ASDM which in energizing opens interrupter springs asdm, whereby the relay CL becomes de-energized. This relay on releasing causes the release of relay S so that the circuit for magnet ASDM is opened, causing the wipers as1 to as8 to step on to contacts associated with the second register. This stepping continues until a register which is off normal is encountered by the assigner. Assuming, for example, that a units switch ucr of a register is off normal, then, when the assigner switch comes to rest on this register a circuit is not complete for relay UC so that relay S is maintained open. Due to the operation of relay CL closing contact cl6, a circuit is completed through the clutch magnet CU whereby the units indicator commences to move. Contacts cudm are closed for a brief period each time a fresh digit is in the process of being displayed, and the closure and opening of these contacts causes magnet IUDM to be energized and de-energized so that the wipers of the switch IU step on to succeeding contacts until wiper iu1 reaches a contact marked by positive potential on a contact of the bank ucr. A circuit is then complete for relay UC whereby the assigner switch is enabled to resume stepping. At contact uc1 the circuit for clutch magnet CU is opened so that the indicator stops, displaying an indication in accordance with the indication on the units registering switch. The first two contacts of the bank iu1 correspond to the blank and "0 " display of the indicator, so that when, for example, a registration exists on the tens of thousands switch tmcr, the indicators registering thousands, hundreds, &c., each require to indicate " 0 " instead of a blank. When wiper tm2 moves to its second position a circuit is complete for relay TMB which at contact tmb1 switches over from the contact corresponding to the blank display of the indicator to the contact corresponding to digit " 0." Contact tmb3 completes a circuit for relay MB which at contact mb1 opens a circuit for relay MC whereby at contact uc1 a circuit is complete for clutch magnet CM. The " thousands " indicator is thus caused to move and display the number " 0 " instead of a blank. In a similar manner the hundreds, tens, and units indicators indicate " 0." The assigner mechanism continues to operate until start key ST is restored, whereupon the circuit for relay CL will be opened at bank as8 when the assigner switch reaches normal position. When it is required to re-set the indicators to normal, contact IR is opened to release any relays UB to TMB that are operative, thereby restoring conditions for indicating a blank display. When the registering switches restore to normal positive potential is applied to the first contacts in the banks of the indicator control switches so that as each register is assigned the associated indicator restores to normal. To ensure that all indicators restore to normal it may be necessary for the assigner switch to continue stepping once past its home position. This is effected by the provision of relay N which is energized if an indicator control switch is off normal, the relay at n1 completing a circuit for relay CL.