GB439112A - Improvements in or relating to artificial lighting - Google Patents

Abstract

439,112. Street, ceiling, wall, &c. lamps. DOWNER, G. V., 5, Lansdowne Place, Guildford Street, St. Pancras, London. May 24, 1934, No. 15521. [Class 75 (iv)] An open lighting unit, suitable for illuminating a comparatively elongated area such as a street, room, or passage, or for illuminating a picture or the exterior of a building, comprises a reflector adapted to concentrate the light from an artificial source into a parallel or divergent beam, the whole of which is intercepted by a curved deflector in the form of an elongated strip and reflected on to the desired area with approximately equal intensity throughout its length, means being provided for partly or wholly shielding the light source from direct observation. In the form shown in Fig. 1, the lamp comprises an electric bulb 1, a reflecting enclosure 2 which is parabolic in cross-section and which has its lower edge and sides extending forwardly to conceal the bulb from direct view, a curved deflector 3 made of metal, wood, paper, plaster, or fibrous material, and preferably painted white, and a metal back plate 4, the far end of the deflector being spaced from the backplate by a metal distance piece 5. The backplate may be wider than the deflector, as at 4<a>, in which case its under surface is painted white. When carried by a standard, wires or rods may be employed to provide additional support for the outer ends of the backplate. The bulb may be adjustable and it may be carried horizontally by the backplate 4 or by the enclosure 2. A number of such lamps may be arranged back to back or end to end, or radially beneath a single deflector of mushroom or umbrella shape. In the form shown in Fig. 3, a single bulb 1 is used with two reflectors 2b, 2<a>, and two deflectors 3 made of iron or other rigid self-supporting material without a backplate. Fig. 5 shows a backplate 4 which is considerably larger than the deflector 3 and is made of translucent glass or like material or has a white reflecting under surface, a sheet 11 of slightly diffusing glass being slung horizontally a short distance beneath the deflector by means of vertical members 12 carrying narrow horizontal strips 13 of diffusing glass. Alternatively, vertical strips of glass may be arranged around the edge of the sheet 11. The backplate may be suspended by chains 10, or it may be mounted directly on a ceiling or a wall. In all forms, the deflector may be straight or slightly concave or convex in cross-section and its reflecting property may vary from one end to the other. Specification 405,016 is referred to.