GB912557A - Improvements in or relating to lighting fittings - Google Patents

Abstract

912,557. Reflectors for street lighting fittings. GENERAL ELECTRIC CO. Ltd. April 11, 1961 [May 10, 1960], No. 16477/60. Classes 75 (2) and 75 (4). A reflector especially for use in street lighting fittings, in the form of a skirt providing or supporting two reflecting surfaces on opposite sides of the median plane which is intended in use to extend across the roadway, each surface concentrating light from a source in the median plane into one of two directions extending up and down the roadway and inclined at 70-80 degrees to the downward vertical, is formed with a cap, the inner surface of which is provided with a plurality of elongated facets transverse to the median plane and arranged to reflect a substantial part of the light into directions lying within one or both of the acute angled sectors banded by a pair of planes perpendicular to the plane of the mouth of the reflector and inclined at not more than 70 degrees to the median plane and one on each side of it. The fitting shown consists of a body 1, e.g. of cast metal, carried by an arm 3 and supporting a lamp 5. The reflector consists of a skirt having parabolic sides transverse to the roadway, a parabolic end 10 reflecting light across the roadway at about 45 degrees to the downward vertical and on end 9 which may be fluted to scatter the incident light and a cap having a series of ridges at right-angles to the median plane having facets 11 which reflect the light across the roadway at about 45 degrees to the downward vertical and facets 12 arranged substantially edge on to the light. Altematively, the ridges may be inclined to the median plane on opposite sides at an angle of at least 45 degrees. Curved facets may also be used.