US 1691131 A
Description (OCR text may contain errors)
Nov. 13, 1928.
. 691,131 C. D. RYDER CONFIGURATED REFLECTOR Filed June 28, 1926 2 Sheets-Sheet l til Patented Nov. 13, 1928.
UNITED STATES PATENT OFFICE.
CHARLES D. RYDER, F COVINGTON, KENTUCKY, ASSILGNOR TO THE CINCINNATI VIC- TOR COMPANY, OF CINCINNATI,
OHIO, A CORPORATION OF OHIO.
Application and June as, 1926. Serial No 118,874.
'= from one filament to the other produces a depression in the height of the beam of light produced. p
Another object of my invention is to provide a configurated reflector adapted for use with a double filament bulb of the nature described, adapted to project two alternate legal light patterns positioned differently as to height.
Another object of my invention is to pro vide a configurated reflector of the nature above described, adapted to be manufactured with uniformity according to the present processes. i
Other objects and certain advantages will a be more fully setforth in the description of the accompanying drawingsforining apart of this specification, in which:
Figure 1 isa front view of the reflector depicting the arrangement of the various zones and the configuration of the zone surfaces. i
Figure 2 is a sectional View taken on line 2*2, Fig. 1, showing the configuration of the lower zone.
Figure 3 is a central sectional view taken vertically of the reflector, sho-wingthe positioning of the light filaments.
Figure tis a diagrammatic view taken the same as Figure 3 and showing the merging of the various zones and the configuration of the zones. 1
Figure 5 is a diagrammatic view taken at right angles to Figure 3 and showing the merger. of the central and lower zones.-
The configurated reflector 1 ofthis invention is concave with the margin 2 preferably substantially circular.
The portion of the reflecting surface most sensitive to the vertical height of the filament producing the light is the middle horizontal zone of the reflector. When a two filament bulb 3 is placed in the reflector with one filament at above the'other 5, and the electric current is switched from the lower filament to the upper filament, the beam emanating from the middle horizontal zone of the refiector is depressed. The height of the beam of light projected from the upper andlower horizontal zones of the reflector is affected by the vertical change in position of the light source to a much lesser degree than that fromthe central horizontal zone. On this account it is desirable to project the upper portionof the light pattern from the middle horizon tal portion or zone of the reflector.
I therefore provide a middle horizontal zone 6 the basic curvature of which is preferably that of a hyperbolic surface of revolution, the actual reflecting surface being. somewhat modified therefrom to provide a proper lateral distribution of the light. The axis A of the generating hyperbola is horizontally disposed and the electric light socket held by the reflector is so placed that one filament ofthe bulb preferably the lower filament 5 of the bulb is positioned on this axis atlthe focal point of the generating hyper be a.
In order to secure the properlightdistribution from this zone, the basic focalizing curvature is characterized by variations constituting configurated light spreading panels.
8 generated by straight line elements, said panels radiating fanlike to a slight extent to provide greater concentration and less width at the top of the pattern. The edges 9 of the panels are on the surface of liy-' perbolic revolution, the generating straight line elements having the relationship of cords thereto. The edges of these panels are preferably defined by planes parallel to the axis. of, revolution, and the fanning is determined by the slight but laterally progressive tilt of the defining planes from the vertical.
The vertical extent of this middle horizontal zone should be greatest over the sensitive portions of its horizontal extent, i. e. those portionsto which the filament most closely bears the relationship of a point source of light. In other words, this zone should be of greater vertical extent over those portions where lines drawn to the extremities of the filament from a point on said surface produce the smallest a; gles. The disclosed filaments are V-shaped in plan view and the fl Fr angles formed by lines drawn between the extremities of a filament and points on the reflecting surface decrease in size to vard the zone margins. The middle horizontal zone therefore increases in verticalv extent toward the margins and is narrowest at the center.
As disclosed this middle horizontal zone is defined by two planes, one'forming an angle of elevation of 30 with the zone axis, the other forming an angle of depression of 30 with said axis, said planes intersecting with each other at a point slightly behind, i. e. outside of the reflector.
This middle horizontal zone, therefore, throws a small triangular spot of light which ishigher or lower according to which filament is burning.
Since the middle horizontal zone projects the upper portion of the light pattern, the zones above and below this zone must project the'rem'ainder or lower portion of the light pattern. As disclosed, the zone 10 above the middle horizontal zone projects that portion of the light pattern immediately below that portion projected by the middle horizontal zone. The curvature of this upper zone is basically hyperbolic as disclosed. This zone is so positioned that the axis of revolution 13 tilts downwardly forming an angle of one degree with the horizontally disposed axis of the middle horizontal zone. These axes intersect with each other at their focalpoint P so that a filament placed at the intersection is focused with regard to both zones. The upper zone is divided into light spreading panels 11 having their edges 1:2 coincidental with'the basic hyperbolic curvature. These panels are geometrically similar to the panels of the middle horizontal zone and are likewise fanned in order to spread the light more at the bottom of the pattern than at the top of the pattern. These panels of the upper Zone are wider than the panels of the middle horizontal zone, the proportions being so chosen thatthe top of the pattern from the upper zone is about the same width as the bottom of the pattern from the middle zone. The light projected from' the upper zone, therefore, continues the triangular pattern, the top apex of which is projected by the middle zone.
The zone 13 below the middle horizontal zone projects the bottom of the light pattern. The curvature of this zone, asdisc'losed, is basically parabolic and the zone is so positioned that its axis 0 tilts downwardly forming an angle of two. degrees with the horizontally disposed axis of the middle zone, said axes intersecting at their focal points P so that a light source at said intersection will be in focus with respect to all three zones. This lower zone is provided with light spreading panels 1 vertically extending, as disclosed, said panels geometrically similar to the panels of the two upper zones but not fanned. The panels of this lower zone are wider than the panels or either zone above.
This zone therefore projects a wide stripe of light positioned in the light pattern below that portion projected by the top zone. The object of the wide lower light is to illuminate .the sides of the road and the ditches ahead of the car. The upper portion of the feature is provided, said depression accomplished by switching from the lower filament to the upper filament. This switching lowers the beam and especially its concentrated distance illuminating top.
It is necessary to so proportion and arrange these three zones producing the proper light patterns so that the zone edges meet properly without involving optical defects which would interfere with the pattern or cause glare or without involving structural defects which would inhibit uniform drawing and polishing of the reflectors.
The curvatures are therefore proportioned so that the zone edges either meet or so that the upper zone edge is slightly in advance of the lower edge thereby avoiding a narrow upwardly turned shelf between the zones.
The upper two zones as disclosed are of the same basic curvature. Since the axes form an angle of one degree, the edges of the basic curve of revolution do not coincide precisely. But this difference in curvature renders the actual lower edge 15 of the upper zone slightly within or in front of (as positioned on the car) the upper edge 16 of the central zone.
This difference is very'slight but the very.
narrow strip of metal between the two zones joining them together is turned downwardly due to the fact that the edges are relatively positioned as described. Consequently, the light reflected from this very narrow strip is projected downwardly and produces no glare in the eyes of a person in front of the car.
The-tops of the panels in the lower zone are decreased in size and small triangles 17 occur between these panels at their tops, the lower apices 18 of these triangles being located at the tops of the lines 19 which define the lower or major portion of these panels. This con struction shortens the cords which would otherwise be formed by the panels at the upper edge. The tops of the triangles also form cords of the basic curvature and the upper edge'iZO of the lower zone therefore comprises a series of cords sufliciently short to joiin the lower edge 21 of. the middle zone without forming corners or depressionssufficient in'size to produce glare from the reflecllU tor or interfere with the uniformity of drawing in production. These triangles project the light from the filaments downwardly and therefore provide no glare or interference with the general nature or outlines of the light pattern.
Thus I provide a configurated reflector especially adapted to be used in combination with a two filament electric light bulb, said filaments at diilerent elevations, said reflector adapted to project light to dili'erent degrees vertically according to which filament is in use. 4
Having described my invention, 1 claim:
1. A concave configurated reflector for automobile headlights, comprising three horizontal zones, the axis of the middle one of these zones being}; horizontally disposed, the axis oi a second zone being disposed downwardly at an angle to the axis of the middle zone to cast light below that cast by the middle zone, said second zone provided with curtature variations constituting vertically ext-end ing panels adapted to spread light horizontally to a greater extent than vertically, the axis of the third zone being disposed downwardly to a greater extentthan the axis of the second zone, said third zone also provided with panels adapted to spread light to a greater extent horizontally than the panels of the second zone, said axes intersecting their tool to provine a common focal point,
22. ll concave configurated reflector for automobile headlig ts, comprising, three horizontal zones each possessed of basic focalizing curvature, each provided with curva ture variations constituting vertically extending panels adapted to spread light to a greater extent horizontally thanvertically, the axes of said zones intersecting at their fool to provide a common focal point, said axes inclined in relation to each other, the middle axis being horizontally disposed, the axis of one of the adjacent zones being inclined down wardly in relation thereto, the axis of the other adjacent zone being inclined downwardly in relation to the axes of both zones, said light spreading panels being of different widths in the different zones to provide variable ligl'rt spread, the panels of the middle zone being the narrowest, and the panels of the lowest inclined zone being the broadest.
3. A concave configurated reflector for automobile headlights, comprising, three horizontal zones each possessed of basic focali curvature, each provided with curvavariations constituting vertically extending panels adapted to spread light to a greater extent-horizontally than vertically, the axes of said zones intersecting at their i'oci to provide a common focal point, said axes inclined in relation to each other, the middle axis being he 'izontally disposed, the axis of the upper zonebeing inclined downwardly in relation thereto, the axis of the lower zone bei g inclined downwardly in relation to the axis of both zones, said light spreading panels being of different widths in the different zones t i provide variable light spread, the panels of the middle zone being the narrowest, and the panels of the lower zone being the broadest, and small triangular panels at the junction of the middle zone and the lower zone, said triangular panels positioned between the verticzlly extending panels oi the low zone to provide curvature at the top edge thereof approximating thecurvature of the lower edge of the middle zone.
in witness whereof, I hereunto subscribe my name.
CHARLES D. RYDER.