GB550910A - Improvements in luminairs - Google Patents

Abstract

550,910. Luminairs. HOLOPHANE, Ltd. March 26, 1942, No. 4035. Convention date, May 27, 1941. [Classes 75 (ii)] and 75 (iv)] A luminair suitable for use in lighting motor vehicle filling stations comprise a lamp bulb 13 'and reflector 14 mounted in a metal hood 10 to which a two-part refractor R is secured by a ring 15, the refractor producing an intense symmetric downwardly directed beam for lighting areas remote from the luminair and a strong asymmetric beam at a comparatively low angle above the nadir for lighting a vehicle or area near the support for the luminair. The symmetric beam is formed by the light passing through concentrating prisms 24 on the outer surface of the wall of the inner part 16 of the refractor, vertical diffusing flutes 26 on the inner surface of the wall of the outer part 17 and large annular prisms 25 at the upper portion of its outer surface. The asymmetric beam is formed by the light passing through annular concentrating prisms 27 on inner surface of the bottom of the inner part 16 and parallel prisms 28 on the inner surface of the bottom of the outer part 17. Raising the light source decreases the upper beam but only slightly affects the direction of the lower beam. The ring 15 and refractor parts 16, 17 may have co-operating notches and grooves to ensure correct orientation and gaskets 19, 21 are interposed between them.