US1235752A - Prjection apparatus. - Google Patents

Description

A. AMES, m PROJECTION APPARATUS.

APPLICATION FILED OCT. H. i916- Patented Aug. 7 1917.

2 SHEETS-SHEET I.

A. AMES, JR.

PROJECTION APPARATUS. APPLICATION FILED O-CT. H. I916.

Patented Aug. 7, 1917.

2 SHEETSSHEET 2.

I J26 Z 6 Z z H219 (ZgOIvze Z LQ.

UNITED A STATES PATENT OFFICE.

ADELBEBT ms, .13., or TEWKSBURY, MASSACHUSETTS; I

rnomc'rxon arrmatrus. I

To all whom it may concern 7 Be it known that I, ADELBERT Antes, Jr., a citizen of the United States, and resident of Tewksbury, in the county of Middlesex and State of Massachusetts, have invented new and useful Improvements in Projection Apparatus, of which the following is a specificatio Y :This invention relates to apparatus for projecting av concentrated beam of light sharply defined on at least one side, and more particularly the invention relates to a non-glare headlight for automobiles and the like which is adapted to project a concentrated beam of light along and below a horizontal plane through the apparatus without projecting substantially any light above saidplane. thus producing a beam which is sharply defined on its upper side.

The invention is a continuation in part of each of the inventions disclosed in my applications, Sr. No. 102,085, filed June 6, 1916, Sr. No. 102,086, filed June 6, 1916. and

7 Sr. No. 123,175, filed September 30, 1916,

certain features of the present invention having been disclosed in the former applications. I

In application Sr. No. 102.085 I have disclosed a-reflector in combination with a light source having portions vertically displaced relatively to a horizontal plane containing the axis of the reflector. As fully explained in the said application. the light radiating approximately horizontally from the portions of the light source displaced below the horizontal plane will strike the reflector at such angles as to be reflected upwardly unless some means is employed to avoid this result. Reference 1s hereby made to the former application for a complete explanation of the cause of this upward glare and for a more detailed description of the means common to both this and the former application for avoiding upward glare due to this cause.

In Sr. No. 102.086 I have also discussed this cause of upward glare and have disclosed certain means comprising deflectors disposed adjacent the horizontal plane. both rearwardly and laterally of the light source,

for downwardly deflecting the light radiat-- ring approximately horizontally in lateral rearward directions from the light source, this means also being employed in the present application.

In application Sr, No. 123,175, I have dis- Speciflcation of Letters Patent.

Patented Aug. 7, 1917.

Application filed Octoher 11, 1916. Serial No. 125,1os.

tion with respect to the focus of the reflector. This method of positioning the light source is also employed in the present ap plication in combination with certain other features.

. The preferred form of this invention comprises a paraboloidal reflector or other type of reflector adapted to project a concentrated beam of light in combination with a. llght Source which is positioned with respectto the focus of the reflector so as horizontally to project a concentrated beam of light from at least approxnnately that portion lying on one side of a horizontal plane containing the 'axis of the reflector, and refracting means positioned in the latter portion of the reflector for downwardly deflecting the light which is reflected upwardly from this por" tion of the reflector. The refracting means is preferably positioned in front of substantially the upper half of the reflector in such manner that the light reflected from this portion of the reflector is downwardly deflected, to relatively near portions of the roadway, the lower half being unobstructed whereby it may reflect a concentrated beam horizontally.

I am aware that there is in use at the present time certain so-called non-glare headlights which employ refracting means in front of paraboloidal reflectors. In one of these headli in the form 0% across the front of the reflector.

prisnis extending entirely With this its the retracting means is construction it is impossible to obtain a beam 7 of light whose upper side is sharply defined, that is. a beam, of light wherein the transition from concentrated light to darkness is relatively sharp. If the prisms are designed downwardly todeflect the light a suflicient fairly concent-ratedbeam of light in a horiound that a zontal direction, it will be great deal of light is reflected upwardly, resultin in a decided lare eflect. This Is due to t e fact that lig it from certain poramount to eliminate upward glare, it is im- 1 zontally. or downwardly, is deflected down-.

wardly by the defracting means, the eflect being somewhat similar to tilting the appa- 'ratus downwardly which, while it may avoid downwardly to deflect in a suficient de the light radiating approximately horizonupward glare, will not aflord a concentrated horizontal beam of light capable of illuminating distant portions of the roadway.

In another type of apparatus heretofore employed, the refracting means is arranged to cover only a portion of the front of the headlight. The defects of this type are similar to those describedabove. Furthermore, this apparatus, has not been designed tally from the light source andstriking the reflector adjacent the horizontal plane conraining its axis; and therefore does not eliminate upward glare due to the causes described in my former application Sr. No. 102,085. ,Moreover, in this type ofreflector, as well as in the type above referred to, no

' provision'has been made for the prevention of upward glare resulting from the light which is reflected from the inside of the transparent container surrounding the light source, when employing the ordinary incandescent lamp or other lamp having a trans- "parent container surrounding the light source. p

The principal object of this invention is to provide apparatus having a reflector adapted to pro ect a concentrated beam of light, a light sources'o disposed with respect to the focus of the reflector that a concentrated beam of light is directly projected from that portion of the reflector lyingon I one side of the horizontal plane containing the axis of the reflector, and having means for downwardly deflecting substantially all light upwardly reflected from the reflector.

This ll preferably accomplish by employing aI series of, prisms covering substantially t lat one'slde of the horizontal plane and also covering the portionof the reflector lying adjacent. the said horizontal plane from which' light is upwardly reflected due to portions of the light source being vertically displaced from the said plane, as above described. although the object may beother and at'large appear.

Another object of the invention is so to dispose the light source with" respect to-the focus of the reflector that the upward rewise attained as will hereinaftermorefully ortion of thereflector lying. on theaaaa raa flection of light radiating approximately horizontally from the source is minimized, if not entirely eliminated, when using refractingnieans as above referred to.

Another object of the invention is to utilize in combination with retracting means in front of a portion of the reflector, a transarent container for the liglit'source which is so shaped and positioned with respect to the light sourcevthat substantially no light is reflectedfrom its inner surface inv such manner as to be projected upwardly. lit a spherical bulb is employed it must be so placed with relation to the light source that no rays from the source are reflected from the inside of thebulb in such manner-as to cross the horizontal plane containing the axis of the reflector on tlie'side of the focus 0 posite from the light source 1 That is; it thc lowerhalf of t 1e reflector is used directly to project a concentrated beam of light. no rays should be reflected down wardly from the inner surface of the upper half of the lamp bulb-in suchmanner as to pass in front of the focus of the'reflector; the light source being positioned behind the focus when the lower half'of the reflectoris used directly to project the concentrated beam. If the upper half of the paraboloidal reflector is employed directly to project the concentratedbeam. the lamp bulb-should be so shaped and positioned with-respectto the light source that no light is reflected from-the inner surfacc-of-th'e lower half of'the'bulb which will crom the aforesaid horizontal plane in the rear ofthe' focus, the light source beingposi'tioned in front of the focus when employing the upper half of the reflector directl beam. I

In the accompanying drawings,'

Figure 1 isa verticallongitudinalsection of one embodinicntof my invention;

Fig. '2 is'afront elevation of the apparatus I shown .in Fig. l

l 1g. 3 is a vertical longitudinal section of another form of the invention;

to project the concentrated act Fig.- 4 is a front elevationof the apparatus shown in 3;

l" 1g. 5 1s a transverse vertical section'taken on the line of Fig. 3:

Fig. this a vertical longitudinal section of another embodiment of the invention;

Fig. i' is a front elevation of the apparatus shown in l ig. 6:

Fig. 8 isa vertical longitudinal section of stilla-nother species ofthe invention; and

Fig.9 is a vertical longitudinal section of apparatus in which the lightsoiirce is improperly positioned withres'pect to the center of the lamp bulb.

The apparatus shown in Figs; 1 and 2" comprises a paraboloidal reflector? having its focus at fyalamp bulb B having a. V shaped light source 2 positioned behind the mamas of the bulb being located slightly in front of the focus of the reflector. The series of prisms 3 are arranged substantially concentrically with the axis of the reflector and they extend down to the line 4. Below the line 4 the transparent front cover is frosted as indicated at 6, the frosted portion extending somewhat below the lowermost point of the light source and having-a depending portion 7 at the center.

Owing to the fact that the light source 2 is positioned behind the focus f of the reflector P substantially all of the light strik- Ing the lower half of the reflector is reflected in or below a horizontal direction as indicated by ray 8. However. the light radiating upwardly from the light source is reflected upwardly, as indicated by ray 9, but by virtue of the prisms 3 the upwardly reflected light is downwardly deflected sufliciently to be projected downwardly. as indicated by ray 11. The light radiating approximately horizontally from the le of the light source which is positioned be ow the horizontal plane containin the axis of the reflector ordinarily is reflected upwardly from the portions of the reflector just below and just above the said horizontal plane, as fully described in my application Sr. No. 102.085. But. in order to prevent this light from being projected upwardly, the frosted glass is provided, the portion 7 being provided in the center to diffuse light reflected upwardly from the portion of the reflector in the rear of the light source and below the axis owing to the fact that upward glare results from portions displaced farther below the aforesaid horizontal axial lane in the rear of the light source than at t e other sides thereof.

The apparatus shown in Figs. 3 and 4 is similar to that shown in Figs. 1 and 2 except that the prisms 12 are disposed horizontally instead of concentrically with the axis of the reflector and that, instead of the frosted glass portions 6 and 7, the prisms 12 are extended downwardly-to cover the same portion of the front of the apparatus as covered by the frosted glass in Figs. 1 and 2. F urthermore the center 0 of the lamp bulb B is positioned behind instead the filament. A depending apron 13. which may be either reflecting or non-reflecting, and which has narrow portions 14 fitting around the sides of the lamp bulb,- may be provided, the portions 14 co onding to the means disclosed in my ap hcation Sr. No. 102,086 for preventing hg t radiating laterally from the light source from being reflected upwardly.

- The glass risms 12 are arranged toextend below t e horizontal plane containing the axis of the reflector only a suflicient amount downwardly to deflect all the light of in front of comes as if from in front of the focus.

v I I is that shown in Fig. 3, Fig. 1 merely illuswhich is reflected upwardly from the pot-- tions of the reflector adjacent the horizontal plane due toportions of the light source being vertically displaced below the plane.

The apron 13 and bands l-lare arranged to prevent from being reflected upwardly the light which radiates approximately horizontally from the li htsource and which would otherwise be re ected upwardly from the portions of the reflector adjacent the hori- The members 13 and l i-accomplish the same result as the portion ofthe prisms 12 lying adjacent the horizontal plane, and-"if properly designed either means is alone cient, although it may sometimes be deslrable to employ both means in combination in v order more certainly to eliminate all upward glare. The difference between the operation of members 13 and 14 and the" lower portion of the prisms is that the members 13 and 14 act upon the light which radiates horizontally from the light source before it strikes the reflector. whereas the. prisms act upon this light after itstrikes the reflector and is reflected upwardly.

Referring again to the position (if the light source with respect to the container therefor, it is noted that any ray of light which is reflected from the inner surface of the-lamp bulb, such as my 18 in Fig. 1 or ray 19 in Fig. 3, passes backthrough the bulb on the side of the center of the bulb opposite to the point of the light source from which the ray emanated and at a distance from the center equal to the distance from the center to the ray emanating from thesource. If a spherical bulb is employed the light reflected from the inner surface of the bulb is' brou ht to a focus as indicated at 22,

V the result being the same as if a second light source of weak intensity were positioned at 22.. With the light source, thefocus of the reflector, and the center of the container relatively di osed as in Fig. 1, all rays re.- flected from t e upper half of the lamp bulb pass downwardly in front of the focus and thus resulting in upward glare. The light reflected from the surface of the lower half focus f, but this light is unobjectiofiable inare reflected u wardly as indicatedat 21,

asmuch as it' is reflected downwardly from the upper half of the reflector and therefore The correctposition of; the light source respect to the center of the lamp bulb trating the fact that upward glare results from an improper relative positiomng of the parts. Where the center or the lamp hull) 13?. is, behind the light source the rays of light, llcli as ray 1th whichare reflected from the upperhalf'of the bulb. pass behind the center 0,.and therefore behind the focus f, and I consequently arereflected downwardly from the lower half of the-reflector. as indicated atz23. The raysof light radiating upwardly "from the image or virtual source 22. such as to ray 2d, are projected downwardly due to the action of the prisms-l2, as indicated at P5 notwithstandina the fact that the rays are ected upwardly from the reflector l 1 e apparatus shown in Figs. *6 and 7 comprises a. paraholoidal reflector l pr I 26 coreringsuhstantially the upper hall of the front of the reflector, and a V-shaped lightsource 2i haringits lower-leg disposed along the axis of the reflector. its apex in so the focus f, and its otherlegdisposed ahore the axis. While'l have shown a V-shaped light'source any light source having a V.- shaped motion, as for example. a conical light source teed hy a spiral filament. will 5 answer the rpm: the requirementheing that the filament shall not extend below the horizontal plane containing the axis" or in ,front oita transverse plane through the line Edwhich passes; through the focus f and 30 thezloweost central oint of the reflector.

all as tally described in my copending application Sr. No. 123,1?5.

'llith the light'source shaped and dis a p as just described and with the various arts accurately manufactured and aflied. santiallr no light is reflected upwardly'irom the lower half of the reflector. it heing unnry theretore'to extend the prisms 26 ow the horizontal plane con 0 taining the axis of the reflector. "The emiment of the invention illusmeanlFigst and i is particularly emcient inamiuch as the particular disposition oit th'elight source wit respect to the f 415 of the reflector is such that a veryconcena f t nted heam ot light is projec in and he low a horizontal don from the entire lower halt oi the reflector. 'llhe center 0 of the bulb B is preferably a Y hehind the light source as Lahore descri so the the image 29 0? i119 eounce 27 H s i: b9 formed behind the focus f and no light therefrom will he projected upwardly.

' lln Fig. 8 llhare illustrated the fact that the apparatus mar be employed in a posr.

'-- ai inverted with respect a that shown in the "-11 ent ti ment the light source 31 should positioned in trout of the focus f of the parah- W oloidal reflector? inasmuch as the :npper half of the reflector is employed directly to reflect the concentrated heamin. and helow a, horizontal direction. The apron 32 eerie spondingto the apron 13 she in Fig. 3

t mounted the ice to extend up-' With this agemenace wardly in of downwardly in order to shield the central portion of the reflector lyin just above the horizontal plane containing the axis, so that rays of light such as 33 will he reflected downwardly as at 3t, m instead of upwardly as at 36 as in the absence of the apron 32. Bands 3? are mount ed on the apron 32 to extend on either side of the lamp hulh as described in connection the side of the light source opposite to the focus. as in Figs. 3 and 6, hut inasmuch as the light source is in front of the focus-the center 0 is positioned in front of e focus on and the image of the source will he formed at 39 in front of the focus f, wherehr rays therefrom such as ray 41. for example, are reflected downwardly tromthe upper half of the reflector, and the mys radiating p5 downwardly them, such as raw 42, are retracted hy the pri so that they are not projected upway.

e the light so must he tioned with ct to the center of the hulh so that. the image of the source is feed on the same side oil the focus as the source itself, as ahore lained, the im must not he formed too tar from the focus. As illustrated in Fig. h for eaple, the light source 43 is positioned a considemhle dis tance in front of the'center c of the hulh l8 wherehy the virtual image is formed at M at a position remote from the focus f of the reflector P. With the image so far hehind the focus, the rays therefrom, such as rays to, are refl so as to dire wideh h om the oil the reflector. e this is not ohjectionahle in so tar as the lower half oil the ector is coned, the light reflected upwardly {from the npperhalt of the reflector may dire so widely from the axis that the p d? can not eientlp retract them to hring th into or hollow a horizontalfldirection, inauch as the lawspertag to the criheal angles of mtion are such that, if the slope of them)? ta of the 'pri are made too great, light is reflected from the rear faces of the risms instead of as'sing into the I prisms. in which event the light is tune to the upper halt of the reflector. a la part of which is'wasted and a part of which finds its way to the lower half of the re flector at such ales as to he refl the tions of the roadway and not wholly to portions immediately in front of the vehicle. Moreover, the weight of the prisms increases in proportion to the increase in the slope of the faces, andthe slope should be maintained as low as possiblefor this-further reason. 7

It will be noted that in each embodiment of this invention a concentrated beam of light is directly projected from substantially half of the reflector in and below a horizontal direction in such manner as to illuminate distant portions of the roadway, that light is downwardly deflected from substantially the other half of the reflector to near and intermediate portions of the roadway, and that light radiating approximately horizontally from the portions of the light source which are vertically displaced with-relation tothe horizontal plane containing the axis of the reflector, is prevented from being projected upwardly.

Only that light which would otherwise be reflected upwardly is diffused or refracted downwardly, and all of the light which is reflected in or below a horizontal direction is permitted to be directly projected to distant portions of the roadway, this result being more effectually attained by making the outline of the loweredge of the prisms irregular. This not only efi'ects a saving of light owing to the fact that only the objectionable upwardly reflected light is acted upon, but it affords a beam of light which is sharply defined on its upper side and which will therefore more effectively illuminate distant portions of the roadway. Furthermore, if the parts are accurately manufactured and are carefully assembled the projected beam of light is not only sharply defined on its upper side, but it is sharply defined by a plane, namely, the horizontal plane containing the axis of the reflector.

It is to be understood that the words above, below, upwardly, downwardly, etc, are employed in the specification and claims merely in a relative sense for the sake of conven ience and conciseness, andthat the appara tus is not limited to use in the sole position or for the sole purpose I claim:

1.. Projection apparatus comprising a concave reflector adapted to project a concentrated beam oflight along its axis, a light source having at least-two substantial d1- mansions, the light source being so positioned with respect to"the focus of the re flector that light is reflected from approximately half of the reflector sutially reflector, the light source parallel with a liorizontalplane containing said axis, and refracting means arranged downwardly to deflect substantially all light reflected upwardly from the reflector, whereby a'concentrated beam of light may be 'projected'a considerable distance along a roadway without producing upward glare.

2. "Projection apparatus comprising a. reflector adapted to project a concentrated beam of light along and below a horizontal plane containing its axis, a light source having portions vertically displaced with respect to said plane and being positioned with respect to the focus of the reflector so as to project a* concentrated beam of light substantially parallel with said plane. and rethe reflector lying onone side of a'horizontal plane containing the axis of the reflector, and a light source positioned substantially wholly above said plane alon the axis on one side of the focus of the re ector, the re maining portion of the front of the reflector being unobstructed, whereby a concentrated beam of light is rejected along andbelow said plane from the unobstructed portion of the reflector and light fromthe other portion of, the reflector is deflected downwardly by the refracting means.

l. Light projection apparatus comprising a concave reflector and a light source, the reflector being so shaped and the light source being so positioned on one side of a transverse plane through the focus of the reflector as to project from the portion of the reflector lying on one side of a horizontal plane containing concentrated beam of light along said plane, refracting means downwardly to deflect the light reflected from other portions of the reflector, and a transparent container for the light source, the container being so shaped and the light source being so positioned within the container as to prevent substantially any light reflected from the inner surface of 'the' container being reflected to the reflector insuch' manner as to cross said horizontal plane on the side of said trans verse Iplane opposite to the light source.

5. rojection apparatus comprising a rethe axis of the reflector a flector adapted to project a concentrated.

beam of light along its axis, a light source having portions vertically displaced from a horizontal plafne containin the axis of the bem' g positioned that the light reflected from the with respect to the locus oi the reflector so that at least approximately halt the' light reflected from the reflector is directly projected along and below said horizontal plane, means for downwardly deflectin the light reflected from other portions of the reflector including substantially all light which otherwise would be projected upwardly, and a transparent container for the light source, the container being so shaped and positioned 1m: Sill"- l'ace thereof to the reflector strikes thereflector at such angles as to be projected vdownwardly.

lid

till

6. Projection apparatus cprising a subtially paraboloidal reflector, a light sourcehaving portions vertically displaced from a horizontal plane containing the axis of the reflector. the light source being shaped and positioned with respect to the focus of the reflector so that light is directly rojected substantially parallel. with said p ane from substantially all of that part of the reflector lying below said plane. and a reiractor tor downwardly deflecting to near and intermediate portions of the roadway the light reflected from the other portions of the reflector. I i

7. Projection apparatus comprising a substantially paraboloidal reflector. a light source having portions vertically displaced from a horizontal plane containing the amis of the reflector. the light source being positioned with respect to the iocus'oi the reflector so that light is directly projected sub stantially parallel with said plane from substantially all oil the reflector lying on one side of mid plane, and a retractor for downwardly deflecting to near and intermediate portions of the roadway the light reflected from the other portions of the reflector.

t 8. Projection apparatus comprising a subdeflecting to nearer portions ot the roadway so a tially all light incident to the rcflr on the. other side of mid plane. portions of the lightso being vertically displaced troramid planes and means to prevent lit. radiating approximately horizontally from said displa portions itrorn being projected upwardly. 1

, 9. Projection apparatus comp a m stantially paraholoidal ector, a light iacaraa source having a V-shapcd section, the light source being disposed on one side oithe locus oil the reflectoralong the amis of the reflector with one end in the focus so that :substantiy all light incident to the reflector on one side oil said plane be directly projected substantially parallel with P said horizontal planeto ant portions oi the roadway, and; retracting means for downwardly deflecting-to nearer portions of the roadway snhstantiallv all light incident to the reflector onthe other side of said plane.

focus of the reflector along thc arms of the reflector with one end in the focus andbcing disposed substantially wholly on one side of a horizontal plane containing the axis of the reflector, whereby substantially-all light incident to the reflector on one side of? said plane will be directlr projected along and below saidhorizontal plane to distant portions of theroadway. and retracting means for downwardly deflecting to nearer portions of the roadway substantially all light incident to the reflector on the other side of said plane.

ll. Projection apparatus coinpg a reflector adapted toproject a concentrated beam of light. alight source disposed substantially whollv on one side of a, transrerse plane through thefocus oi the reflector and substantially wholly on one side oil a longitual plane Contag'the axis of the reflector. so that light isdy proflected from other portions oi the reflector w toward said horizontal plane. I v 12. Projection. apparatus cornp a concave reflector adapted to project a con centrated n otlight along its axis, a light so hating at. least one substantial ension, the light source being so positioned with to the focus of the reflector that light is reflected from approach rnatelv hall of the reflector substantially parallel with and below) a horizontal plane containing mid axis. and retracting means arranged downwardly to deflect substantially' all light reflected upwardl from the reflector. whereby a concentrated Mani of light may be projected a considerable dis tance along a roadway without producing upward glans.

Signed by are at n,

this It day of @ctober, 119116.

clnisetts till

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