US1825084A - Reflector for automobile headlamps - Google Patents

Description

REFLECTOR FOR AUTOMOBILE HEADLAMPS Filed Aug. 15, 1927 gwuento'a a. a mul Patented Sept. 29, 1931- re'rsl stares CLARENCE A. MICHEL, or CLEVELAND, oEIo, nssreivon rro. ii LCQm-EM 100mm- TION, or DAYTON, OHIO, A coarona'rron on E a v EE LEoToE FOB. AeronroBr i Application filed August 15, 9 .saa 'm21 67'. J

This invention relates generally to reflec} tors for automobile headlamps and more particularly to one designed to eliminate striated road illumination. It is well known that a beam from a headlamp is the composite of many beams coming from various sections of the headlighting device and in order to illuminate the roadway uniformly it is necessary to have a smooth even beam, that is one which 1s lacking 1n areas of low.

as to blend as well as possible the light com- I ing from said sections.

In some types of reflectors this is somewhat difficult, particularly in long focal length reflectors as the beam reflected from a long focal length reflector is more concentrated, or has less angle ofdivergence than a beam reflected froma short focal length reflector. This is obviously true,

due to the fact that in a long focal length reflector the source of'light subtends at any one point of the reflector, a smaller angle than in a short focal length reflector. The need of blending the light ina long focal length reflector is accordingly greater.

It will be understood, however, that my invention is equally as applicable to a short focal length reflector as a longfocal length one, and it will also be understood that although I have illustrated my invention applied to a reflector composed of four sections, that it can be used in connection with reflectors having a lesser number of sections.

With the above recited objects in view the invention consists in providing a plurality of flat flutes at definite points in the reflector whereby the beam is spread at intensity.

zontal, andin a combination of vertical-and those points pro-vid-inggthe desired blending of the various portions of the beamand completely- I eliminating streaks "of high and low In tlie drawings Ih'ave sho n one form of reflector ifOI carryingout my invention; and in which Fig- '1 is a faee view ofa reflector; Fig. 2' is ja "longitudinalsectional view of the-"same and F-ig; 3 is a sectional detail. 7

reflector preferably'formedo-f a single piece -r and comprising the upper section 11', the lower sections 12; the intermediate section's- Band 14 and the transition surfaces 15' and 16. This reflector is preferablya longfocal length reflector and the upper and lower halves may have the same or differentsfoc'al pointsas preferred, and furthermore-the top and bottom'secti'ons maybefmod-ified from. a; true. .parabola or tilted with referenceto. theaxis of the reflector in order that all. of the rays may be reflected below-the h'ori-;

, i i 0. Referring tothe drawings 10 indicatesthe g zontal'as illustrat'e'd in Fig. 2 by dotted lines. a

' These flutes are: formed 'by iflattening out the surface between two parallel lines'onathe.

reflecting sur facei- By 'flattening the a surfface between-the lines the beamcomingfrom that particular flattened portion is spread. in a vertical direction when I the flute'is horihoriz'ontal when the flutes are concentric; F

"By-the proper selection and placementoft these flutes, the light from any one-section or-lany one portion of th'ereflector section can be spread out in a substantially verticaldirection;thereby helpingto blend the light of that section with the light from other sections of the reflector.

This is particularly advantageous in a fixed focus headlamp Where it is desirable of a focusing mechanism.

to have an overlapping or blending of the beam portions so as to minimize to all appearances the variations in beam pattern caused by variations in filament placement Within the reflector inasmuch as such Variations cannot be compensated for by means In the section 11 the flutes 17 are concentric, and in section 12 are both concentric at 18 and horizontal-M 19 while in section 13 they are horizontal as at 20 and concentric as at 21 in section 14.

In Fig. 3 I have shown how the flat flute spreads the beam, the reflected ray from the original'surface being shown in dotted lines and the rays from the surface after fluting being shown in full lines. 7 p

The arrangement of flutes herein shown and described for giving a radial'sprea d can be used in connection with a vertically fluted reflector such. as disclosed in my Patents,

'Nos..,1,5;13-,844 and 1,513,845.

It will also be understood that these flutes,

' instead of beingflat can be concave or convex.

I claim is 1. A reflector for use with a plurality of separately energizable light sources to provide a high beam and a low beam, provided with top and bottom zones and a central zone extending from one side edge of the reflector to' the other, said top and bottom zones having their axes downwardly inclined with respect to the centralzone, one of. the two zones first mentioned being provided with a horizontally extending fluted portion blending into the adjacent portion of the reflector without abrupt break in ourvature and arranged to give increased vertical spread to the light reflected therefrom to smooth the beam. 7

,' 2.:A reflector for use with a plurality ofv independently energizable light sources to provide a high beam and .a low beam, provided with top and bottom zones and a central zone extending from one side edge of the reflector to and. other, said topand bottom zones having-their axes downwardlyinclinedewith respect to the central zone, one of the two zones first mentioned being provided with an arcuate fluted portion in the form of a conical surface substantially concentric with the reflectoraxis and smoothly blending with the adjacent reflecting surface for giving greater vertical and lateral spread to the light reflected therefrom to smooth up the beam.

In testimony whereof, I hereunto afiix my signature.

' CLARENCE MICHEL.

,Having thus described my invention, what

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