GB417783A - Improvements in and relating to signalling systems for controlling road traffic - Google Patents

Abstract

417,783. Road signals for controlling traffic. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London. July 10, 1934, No. 20223. Convention date, July 19, 1933. [Class 118 (ii).] Synchronously control. led signals are provided along a highway together with signals normally showing green to the highway and controlled by road pads in side roads, the operation of a road pad allowing the associated signals to pass through a cycle in synchronism with the synchronously controlled signals. As shown in the Figures signals at points A are continuously driven by local controllers synchronised once during each cycle by a master timer 16. At points B the signals normally show green to the highway but when one of the road pads 62, 63 is operated the associated equipment drives the signals through a cycle, the cycle starting when the synchronising pulse is received from the master timer. The signals at A are operated from motor 4 through clutch 13. At each revolution of cam 33, which corresponds to a cycle, the spring 37 co-operating with cam 33 closes contacts 35, 36 so that magnet 15 operates and opens the clutch. At this time, however cam 25 of the master timer, which is either a cam on one of the local equipments or on equipment at a separate station, opens contacts 27, 28 to break the circuit through magnet 15 so that the clutch closes and the controller passes through another cycle. At station B clutch magnet 58 is normally energized so that the equipment, apart from the motor 44, is stationary. If one of the road pads 62, 63 is operated the magnet 74 is energized and moves switch 65 to connect lead 61 to contact 77 so that clutch magnet 58 is held over synchronising lead 32. When cam 25 at the master equipment next opens contacts 27, 28 the circuit of magnet 58 is broken so that clutch 50 closes to drive the signals at B through one cycle. When cam 52 moves, arm 54 resets switch 65 and contacts 55, 56 are opened so that magnet 58 remains deenergized until arm 57 again drops into recess 53 in cam 52. Magnet 58 then re-energizes, de-clutching the controller 41 and leaving the right of way with the highway until one of the road pads is again operated. The cams on the equipments at A and B may be set to allow a vehicle passing along the highway at a predetermined speed to proceed without interruption. The synchronising pulse from the master equipment passes out when all the equipments are showing green to the highway. Specification 393,707 is referred to.