GB482777A - Headlights for vehicles - Google Patents

Abstract

482,777. Vehicle lamps ; reflectors. AKTIEBOLAGET TIMBRO. Feb. 22, 1937, No. 5250. Convention date, Feb. 22, 1936. [Classes 75 (ii), 75 (iii), and 75 (iv)] In a vehicle lamp in which a main light source and reflector for long distance lighting, and an auxiliary light source and reflector for anti-dazzle close range lighting, are combined as a single unit, a vertical section through the axis of the auxiliary reflector is elliptical at the front, and at the rear is such that rays from a light source placed in or close to the posterior focus of the foremost elliptical part are substantially parallel after being reflected by said rear portion.. Fig. 1 shows an auxiliary reflector 1 having a paraboloidal rear part 1a with its focus at 2 and merging continuously into an ellipsoidal front part 1b with its foci at 3 and 4, rays from a horizontal transverse filament 5 passing through the focus 3 being formed into two beams 6, 7 and 8, 9 by the front and rear parts respectively. The axis of the paraboloidal part may coincide with or be slightly inclined downwardly with respect to the horizontal axis x-x of the ellipsoidal part. Alternatively, the elliptical vertical section of the front part may merge continuously or discontinuously into a parabolic horizontal section, Figs. 2a and 2b (not shown). Figs. 4a and 4b show a lamp casing 26 containing a main reflector 27 and its associated light source 28 and convex cover glass 29, and an auxiliary reflector 1 with its associated light source 30 and a spherical recuperating reflector 31, the auxiliary beam passing through a hole 32 cut in the main reflector 27. The cover glass may be in the form of a Fresnel lens, with vertical flutes to spread the light laterally, and with a plain toric portion for the passage of the auxiliary beam, Figs. 5a and 5b, (not shown). Fig. 6a shows the auxiliary reflector 1 lengthened in front so as to project some light downwardly and rearwardly through a window 36 to illuminate the front of the vehicle. The lower part of the paraboloidal rear portion of the reflector may be screened by a crescent-shaped shade 25. British Specifications 418,484, 437,001, and U.S.A. Specification 1,946,379 are referred to. The Specification as open to inspection under Sect. 91 comprises also (1) a convex cover glass of such curvature that substantially all the rays pass approximately at right-angles through it, and (2) a lamp in which the main reflector and its light source is dispensed with, (a) by continuing the auxiliary reflector below its axis and giving it a tilt to project through a slit-like opening in the lamp casing a combined long distance and close range beam of light, or (b) by mounting the lamp so that it may be dipped when required. In the form shown in Fig. 11b (Cancelled) the lamp 41 is mounted on a horizontal axlebearing 42 surrounded by a return spring 43 and operated by a lever 45 attached to a wire 44. The wires from a pair of such lamps pass over pulleys to a control device on the dash board. This subject-matter does not appear in the Specification as accepted.