US 1559930 A
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Description (OCR text may contain errors)
' Nov. w25. 1,559,939
L. A. BAN
Filed May 19, 1924 l a fan shaped beam of light, such as projectrectly ahead than '20 Patented Nov. 3, 1925.
UNI-,TED STATES '1,559,930 Pifrlazlsi'rv OFFICE.
LOUIS A. BEAN, or DENVER, ooLonAno AUTOMOBILE HEADLIGHT.
Application .filed May 19, 1924. Serial No. 714,353.
To all 'whom t may concern: l
Be it known that I, Louis A. BEAN, a citizen of the United States of America, residing at Denver, inthe county of Denver' and' State of Colorado, have invented certain new and useful Improvements in Automobile Headlights, of which the following is a specication. e l
This invention relates to automobile headlights more particularly of the type as disclosed in the applicants prior application Patent No. 1,480,364, filed April 16, 1923, patented January 8, 1924, and has for its principal object the provision of a reflector for an automobile headlight which will give' ed by the reflector of said prior application, but which will give a more intense light (liwould the previous reflector. y
Another object is to provide a reflector whose projected beam will be relatively narrow' in lvertical projection so as to prevent glare to an approaching driver.
A' further object ci" the invention is to efiicientlyv incorporate with an automobile headlight a light of lesser intensity which may be used as a parkin light and may, if desired, be provided wit a color screen so as to produce a novel and ornamental effect. A still further object of the invention is Y vto provide a pair of automobile headlights which together will project a wide band of brilliancy ahead of an automobile extending through a wide horizontal and narrow vertical band.
. Other objects -and`advantages reside in the detail construction of the invention, which result in simplicity, economy, and efiiciency, andy which will become more apparent .from the following description.
In the following detailed description of the ,invention reference is had to the accom? panying drawing which forms a part hereof. Like numerals refer to like parts 'in all views ofthe drawing and throughout the descriv tion.
' In t e drawing.: j Fig. 1 is a face view of my; improved headlight. Fig. 2 is a cross-section taken on the horizontal-center line of the'saine, line 2 2,
Fi 1. y l
Fig. 3 is a similar cross-section taken on the vertical centei` line, line 3 3, Fig. 1.
' its axis.
Fig. 4.is a diagrammatic plan illustrating the projection of a pair of my improved headlight-s on an automobile.
In Figs. 2 and 3, typical light beams have been illustrated, the incident rays being shown in solid line and the reflected rays being shown in broken line.
.I attain the principal objects of my invention by means of a novel reflector, 10, in`
which is placed a light source 11. vThe relector 10 comprises two horizontally Aop posed reflecting surfaces 12 and 13,r one tof U each side of the light source 11.y The surface- 12 is substantially a semiparaboloid, while F'.- is practically 4one-half ofthe reflector` as dise` the surface 13 is concave and comprises what' closed in the applicants said 'prior a plication. A horizontal Asection through tlie surface 13 discloses practically "anellipticalcurve with the light source placed on the shorter axis of the ellipse. A` horizontal section through'the surface 12 discloses a--par'abolic curve with the light source plaged on The curved edges of the open sides of the portions 124and 13 are tangentiall connected by straight edges 14 and 15. Xtending from the straight edges 14 and 15, t'o a. point back of the light source 11, are'two vertiecally opposed triangular shapedfreflectin surfaces or parabolic planes 16 and 1 which, ,when cut by a plane parallel to the face of the refiector,r disclose straight lines,-
and when out by aperpendicular plane, at "ffl:- ,9C
right angles to the face of the reflector,y disclose substantially a parabolic curve. The triangular shaped surfaces 16 and'l'l are tan ent throughout to bothv the parabolic. sur ace A12 and the` concave vsurface 13.
The refiector therefore comprises :four distinct reflecting surfaces, to-'wit,-12,'13, 16 and 17 having a. common apex at the axis 'of the reflector. The triangular surfaces 16 and 17 present substantially right triangles, one
le of each coinciding in position and length 10i wit/h one of the two parallel lines-14 and l5,
Aand theother leg of .eachl 'ng on the vertical axis of the reflector. f he llatter legs are the lines of joining tonthe semi-parabplic surface 12 while the hypotenuse of eachia're 105.
the lines of joining with the concave surface 13. It will be notedthat this construction places the light source to one side of the;v
The eilect of the reector contour on the rays of light will rnow be described.l The rays of light projected toward the surface 12 of the reflector, designated by the numeral 18, will be reflected substantially at right angles to the reflector opening, as indicated at 19 These rays illuminate the area directly ahead of the automobile as indicated at 19', Fig. 4. The rays Which are projected to- Ward the surface 13 of the reflector will be reflected in a Wide fan shaped beam. '.lhese rays will illuminate the area to one side of the automobile, as indicated at 20, Fig. fl.
The action of the surface 13 upon the light rays has been Well described in the said prior application and will be described briefly herein. The rays which strike the portion 13 of the reflector nearest the light source will be directed at an angle to one side thereof, as indicated aty 21,A as the distance from the light source is increasedl theangle of these rays 'with the axis of the light source Will also increase, reaching their maximum angle at the portion ofthe reflector designated at 22'and indicated by the rays 23. From this point on to the eX- tremity of the reflector the angle of the reflected rays` with the axis of the light source decreases, as indicated at 2l. The action of .the light rays on the triangular surfaces 16 and 17 directly above and below the light source 11 is indicated in Fig. 3, the rellected rays 25 being directed straight for- Ward.
The angle of the beams at any line in the surface 13 radial to the light source 11 Will vary from that of Fig. 8 to that of Fig. 2 depending upon its angle from the vertical center line.
lt is desired to be understood that, therays indicated are more or less theoretical and assume that vthe light source is -a point of light. Practically, however, such a point 'of light is impossible to` obtain and the angle of the light .rays Will `vary and the rays themselves'willdifuse and interiningle over the entireli'ghted area.. 4'
It is intended that two of the lreflectors 10 be carried by an automobile, as indicated in Fig. When thus Vcarried the from thefportiony 13'fo. the reflector will be cli-- rected vtoeahaside of the automobile as in dlcatedat QQ'ythe raysfrorn the portion12 of the reflector `Will be directed substantially* Straightahead of the automobile, as indi-" cated at 19", the' result being, that a `very Wide area"v ahead of the automobile is brilliantly illuminated, While the rays, which in the usual parabolic conoid type or the reflector are directed upward or downxi'fard atfv various angles, are spread in a Wide fan.
' sha ed beam 'vine useful llumiuation- Lu Fig;V Il, the right andleft headlights are designated bythe numerals and 26 tweeen espcctively. The right headlight 25 spreads its side rays to the left of the automobile Whi'le the left headlight 26 directs its rays to the right thereof. The reflectors may, of course, be' interchanged from the oosition shown in 4, 'so that the left yieadlght will direct its rays to the left and straight ahead While the right headlight directs its rays to the right and straight ahead.
The renector lo, is preferably, placed /vithin a housing 27, in the face of which a lens 29 is carried, the light source 11 being on the center linev of the housing. .The contour of the open side of the housing 27 is similar to the contour of the open side of the reflector 12, but, since the light source is concentric to the housing' 27 and eccentric to the reflector 10, crescent shaped section of lens 28 will he left between the reflector opening .and the end of the housing open ing which Will not be illuminated by the light source 11. This section of lens may be frosted or colored, as indicated in Fig.
1, to act as a parking light and isilluminatcd from a second light source 29,' placei` relatively close to the light sourcell so as to be partially covered by the projecting edge 'oit' the reflector 10. The rear side of the reflector 10, indicated at 30, is brightened or silvered to act as a reflecting surmeans cf set screws 34. The lens 29 and the reflector 10 are held in place by a channel run 35 which 1s formed in two sectlons clamped together by ineansoflclamp. screws" 36 It is desired to,y be understood that it is not essentialv to 'the invention that the por, tions 12 and .13 of the reector join on a Vertical line passing through the light source, since it has been found that there is kno noticeable difference in efficiency pro- "duced by placing the light to source 11 ,at a
short distance to the right or left of the joining line. t is also desiredto he understood that the curves designated as elliptical and parabolic are not necessarily limitedv to pei-rect paraboles and ellipses, but ma be' i-inade any substantial variation thereo A..
@While a speci-fic form of the. improvement has been described and illustrated herein, it desired and understood that the saine may be'v'a'ried, Within the scope of the 'combination in a reflector having a tally placed oblong opening,
appended claims, Without departing roin thespirit of the invention.
',HavingA thus described the invention, what I claim and desire secured by Letters Patent-.isz
1. In .a light projecting apparatus, the
the vert saidreflector being toone side of tl'ae vertitially a parabola in each comprising .surfaces presenting vflect rays horizontally to one side or said axially reflected rays.
2. YThe combination in a reflector, having Aan'oblong opening defined by two parallel straight lines tangentially connected by semi-circular ends, of two triangular-sliaped surfaces of a bascequal to the length of, and coinciding with, said two parallel f straight lines and extending back on a sul)- 'stantially parabolic curve to the apex of said rel-lector; a third surface representing substantially a semi-paraboloid tangentially joined toA saidv two triangular surfaces on the vertical axis of said reflector and having a base coinciding with one of said semi-cireular ends and a fourth concave surface tangentially joining the opposite edges of said triangular surfaces and having a base coin ciding with the other of said semi-circular ends.
'in light projecting apparatus, the combination ot a rel-lector having an oblong opening deiiiied by two parallel straight vlines connected by semi-circular ends, said reflector comprising, a pair of similar triangular-shaped surfaces having a com rrion apex at the axis of said reflector, said triangular surfaces presenting right triangles one le'g ot each coinciding in position and length with oneof said two parallel lines and the other leg of each lying on the vertical axis ot said reflector; a parabolic surface, conil'irising a senii-paraboloid tangen` "tially joined to said two triangular surfaces on said vertical axis and having a base coinciding with one ot' said semi-circular ends and a concave surface tangentially joining said triangular sides along the hypotenus otx each triangular surface; and a light source arranged in locus `with said rciector whereby said triangular-shapedand said parabolic surfaces will project substantially parallel rays of light forwardly and said concave surface 4will project diiusing rays of light to one side' of said parallel rays of light. j
ln testimony whereof, l afiix my signature.
Louis A. BEAN.