GB541809A - Improvements in and relating to illuminated mimic diagrams - Google Patents

Abstract

541,809. Railway signalling. GRAY, J., and METROPOLITAN-VICKERS ELECTRICAL CO., Ltd. June 10, 1940, No. 10109. [Class 105] [Also in Groups XXXVIII and XXXVI] In an illuminated mimic diagram for railway signalling systems in which the track sections are represented by rods or strips of transparent or translucent material on the face of a panel, illumination is provided by introducing light into one or both ends of a rod so as to pass along the rod and be reflected or scattered outwardly. As shown in Fig. 1, a translucent rod 2 is mounted in a groove 3 in a panel 1 and is secured at its ends in lamp holders comprising hooded portions 4 passing through the panel and fixed thereto by non-conducting sleeves 8 fastened to the portions 4 by spring clips 10. The lamps 6 are of the telephone type and are secured in the holders by spring clips 9 which also form electric terminals. The lower surfaces 11 of the rod are inclined and polished or silvered to reflect light outwardly. In a modification the ends of the rod are bent to project backwardly through the panel the bent-back ends being illuminated from the rear. In the modification shown in Fig. 5, the rod 14 is formed with screwed rearward extensions 15 which pass through the panel and carry lamp holders 16. The two lamp holders in Fig. 5 may be combined in a single unit mounted in an aperture in the panel. Coloured filters 17 or lamps may be used.