GB674401A - Vehicle signalling system - Google Patents

Abstract

674,401. Road traffic signals on vehicles. HOLLINS, J. R. July 25, 1950. [Sept. 17, 1949] No. 18573/50. Class 118 (ii). In a vehicle signalling system comprising groups of clearance lamps 20, 20<SP>1</SP> disposed on each side of the vehicle together with left and right-turn indicator lamps 30, 30<SP>1</SP>, a control switch 10 and circuit is provided whereby at night the clearance lamps are normally illuminated steadily and a turn is signalled by flashing both the clearance lamps and turn indicator lamps on the appropriate side whilst the other clearance lamps remain steadily illuminated. Day-time operation is similar, the control switch 10 being turned through 180 degrees to a position in the which clearance lamps remain extinguished until a turn is signalled. An alternative system employing a similar circuit Fig. 2 (not shown) dispenses with separate lamps for clearance and turn indication and employs common two-filament lamps. As shown, switch 10 is in the " night " position and a connection extends from power source 5 through arms 16, 17 and contacts 21, 21<SP>1</SP> to illuminate both groups of clearance lamps steadily. To signal a right turn handle 19 is moved counter-clockwise until arm 14 engages contact 31 and arm 13 engages contact 21'. The left-hand clearance lamps 20<SP>1</SP> continue to be illuminated steadily whilst the right-hand turn indicator lamps 30 are flashed in the circuit extending through flashes unit 32. In addition, a relay 33 included in this circuit operates contacts 38, 39 to flash the right-hand clearance indicator lamps 20. A left turn is signalled in a like manner by moving handle 19 clockwise, the left-hand lamps being flashed by unit 32<SP>1</SP> and relay 33<SP>1</SP>. Tell-tale lamps 25, 25<SP>1</SP> are operative from relays 23, 23'. For day operation, switch 10 is rotated through 180 degrees by placing handle 18 in the lower position. The circuits to lamp groups 20 and 201 are broken and the lamps are normally extinguished until a turn is signalled. Arm 14 may be arranged not to engage contacts 21 or 21<SP>1</SP> so as to avoid illuminating the clearance lamps steadily when signalling a turn during day operation. An " emergency stop " signal is made by rotating the switch until arms 13 and 14 engage contacts 36 and 36<SP>1</SP> whereupon all the lamps on both sides of the vehicle are flashed.