GB665939A - A traffic light pillar - Google Patents

Abstract

665,939. Luminescent applications. MARTIN, H. July 18, 1949, No. 18802/49. Class 39 (i). [Also in Groups XVIII and XI] A traffic light pillar of the type having a linear light source disposed axially of the pillar and surrounded by a plurality of reflectors 5 arranged radially thereto and parallel to the axis of the pillar so that the illuminating rays fall on the reflectors, has a discharge tube 8 enclosed in a coaxial translucent or transparent protecting tube 9. One or other of the tubes 8, 9 may be coated with a fluorescent substance or substances. The tube 8 is vertically mounted in the roadtraffic pillar to illuminate four vertical reflectors 5. The reflectors have a uniform curvature in section or one which increases towards the outside. Reflectors 4, 6 surround the tube at the top and bottom and hoods 11 directed obliquely downwards are mounted between the reflectors 5 to cut-off light in an upward direction. The hoods 11 and reflectors may be of coloured translucent material, if desired. In addition to the discharge tube 8 or the protective tube 9, the reflectors 4, 5 and 6 may be provided with fluorescent substances to convert ultra-violet radiation to yellow light to increase efficiency. The reflectors may also be provided with phosphorescent substances so that the pillar is visible when the tube is not switched on. The head and foot of the pillar may contain lamps 15 in which case they are made partly translucent. The lamps in the foot may be used also to heat the air surrounding the discharge tube in cold weather; as an alternative a heating resistance 13 controlled by a thermostat] 4 may be used. In a modification, two reflectors 5 may be used instead of four and the discharge tube may be so positioned slightly off-centre to illuminate one more than the other. The upper part of the protective tube may be darker in colour than the lower part and a shield separating the two parts may be provided; this arrangement allows the pillar to illuminate a surrounding traffic island without allowing bright light to shine upwardly.