US1400926A

US1400926A - Headlight

Info

Publication number: US1400926A
Authority: US
Publication date: 1921-12-20
Anticipated expiration: 1938-12-20

Description

W. G. WOOD.

HEADLIGHT.

APPLXCAUDN FiLD AUGy 5 191B. RENEWED MAH. 3,1920.

nu A@ muur o. Woon; or s'enmnorsoo, sssrcmon rro nnnxznnnr morro.'A

conromnorr, on sur mnemoc, onrirrozmm, A oonPonA'rIoN or :NEVADAn HEADLIGHT.

Specification of Letters Patent.

Patented Dec. 20, 1921i.

Application ledlugnst 5,1818, Bei-lil No. 248,808. Renewed March 8. 1920. Serial Ho. 883,084.

To aia' whom t may concern:

`Be it lrnown that I, WILLIAM G. Woon, a citizen of the United States, residirig at San Francisco, in the countyA of San rancisco and State of Californie, have invented-new and useful Improvements in Headlights, of which the followin is a. specification.

This invention re etes to' improvements in light projectors, and more particularly to headlights, such as ere adapted for use on 1illirtomobiles, lowmotives, street eers and the This application is a continuation in part of m f prior application Serial No. 209 834 tiled anu-ary 2, 1918, which has become hat; ent No. 1,324,288 dated December 9 1919.

Lamps of the headlight type snc ns are commonly empio ed on automoiles end the like, are .ordinnrily provided with e, pureboh'c or like reiector'to concentrate the rays and tm permit the projection of a single beam of intense light. V

In actual practice it is found impossible to regulate the vertical height of the beam projected es imperfections in the parabolic reflector and the size of thelument produce n cone-shaped beam and not a series of )arallel rays, as theoretically intended. Vhle the source oflgbt itself may4 not be of great intensity the-projection-and concentration of its rays produces n light beam so intense es to be in effect blinding to the eyes of npprouching drivers or pedestrians, artcu' larly if the fieldovf the rejectedl eem is entered. Many attempts ave been mede to prevent Vthe glaring oi" blinding elect thus produced-.end to regulate the vertical height of the rays projected. For instance, dimmers, shutters, refractory lenses and other devices have been empio ed, but the general result is e mere reduction of the lighting power of the lamp.

One of the objects of the present invention is to overcome this defect and to provide n headlight which permits concentration und projection of the light rays on thc roadway ahead of the nutorno ile, and which also permits spreading of the beam laterally while confining it vertically, that is, the project/or or reflector from which the light emanntes may be so arranged that no light rays ure permitted to project above n. horizontal line driwn 0n .f1 level with the lump.

Another object of the invention is to provide a reflector which projectsaconeentrated or crossing line of the rays, thus permitting .a reduction in the size of the exposed area of the window to half en inch or less in width.

Another objectV of the invention is to, provide e novel shutter arrangement adapted to be interposed between the transparent alperture und the projecting reflector, said s utters pei'mjttin Aam unobstructed projection of substantie y all the light rays-from the interior of the lomp outwardly and at the seme time servin the function of shutters when the lamp 1s viewed from the ex# terioigvas they completely hide the source of light and the apparent source, the blades overlapping on the line of vision unless the eye is below the lamp and in the projected field of light.

Another object of the invention is to ,provide menns'for converging or diverging the light boem as it passes through the trains` parent aperture to increase or decrease the oren liehted, und to produce n more uniform and o? light.

Further objects will hereinafter appear.

The invention consists of the parts and the construction, combination und arrangement of parts as will be hereinafter more fully desi'ribed and claimed, having reference to the accompanying drawings, in Which- Figure l is e central, vertical, longitudinnl section through the lump.

Fig. 2 is a diagrammatic view showing how the light beam may be converged or diverged by placing n lens in the transparent aperture.

Fig. 3 is a plan view partly in Section.

Fig. i is n front view of the lamp.

Figs. 5 and 6 nre diagrammatic plan and side elevations of the projecting reflector, res ectively.

eferring to the drawings in detail, end particularly to Figs. l nnd 3, A represents o. casing iu the forward end of which is placed nn oblong narrow window or transparent npel'ture Q. The casing proper is shaped as shown, end is comparatively narrow when viewed from the top, es Shown in Figs. l and Il, und fzousists of two Sections 3 end 4 llO sitipn within the lamp casing. Comparatively few light rays are obstructed by the shutters 20, first, because they always assume a parallel position with relation to the prov jected rays, and, secondly, because they are so thin as to offer a comparatively small surface against the rays. The intel-position i of the shutters 20 between the transparent opening and the projector 1l positively prevents the forward projection of anything but parallel rays and they also serve as a means for concealing not only the source of light, but also the apparent source of light when the lamp is viewed from the exterior.

This can be readily understood when it is realized that the average person stands much higher than the lamps and will therefore ,look down upon same, for instance, on an angle assumed by the arrow a.. The lamp when viewed from this angle apparently has nosource of light, as all that can be seen will be the upper surfaces of the shutters 20. They form an obstruction to the line of vision, both as far as the source of light is concerned and also the projector 11 when viewed from the angle indicated. It is therefore necessary forain observer to stoop down into alinement with the shutters before the apparent source of light becomes visible. The projector or reflector 11. is adustable with relation to the cross rod 10 y means of an arm 30 and a` set screw 31. It may also be quickly removed with relation to the bearings l() as the caps of the bearings are hinged, as at,12. and secured when the reflector is inserted by spring latches 12b.

If it is desired to remove the projector 11 it is only necessary to lift the heads of the latches 12b to swing the same out of alinement with 'the caps as they are supported by pivotally mounted links 12C. rlfhe caps can thus be raised and the cross shaft 10, together with the projector carried thereby` may instantly be removed for cleaning, adjustment or other purposes. The arm 17, by which the angular position of the projector is controlled,` is segment-shaped or rounded. on

i its lower end and engaged by a friction shoe 17 to frictionally hold it in any adjusted position. The rounded portion is also notched as at 1T" to normally secure the projector in the intended position. and also to permit the operator to' feel or udetermine when the intended position is reached.

The forward portion of the lamp casing is preferably wedge-shaped, as shown in Fig. 3, to conform with the shape of the projected beam and -it is therefore essential that the shutters 20 be of a similar shape. This feature is,.,however, 'more or less unimportant, but shows that it is possible to considerably reducethe size of the lamp, if desired. The weight of the bell crank arm 24 and the connecting rod 23, by which the shutters are moved, may be offset as in the vaperture in the casing,

present instance by employing a counterbalance spring 40. single shutter 41 may be placed within the reflector and cage to prevent forward projection of direct rays of light, if it is desired to eliminate the use of the shutters 20.

By referring seen that a plano convex cylinder lens has been placed in the transparent aperture.Y This lens has two functions, first, that of converging or diver-ging the light beam projected, and second, that of producing a more uniform light field.

By referring to the diagrammatic view shown in Fig. 2 it will be seen that positioning of the lens behind the focal center 50 of the beam diverges the beam as indicated by the lines 51., while placing the lens ahead of thefocal center converges the beam as shown by lines 52.

Practical experience has proven that these results are obtained, and also that a more uniform field of light is produced whether to Figs. 1 and 3 it will be I the lens is placed in one position or another,

' facturer -may'dictate I wish it understood that various changes in the form, proportions and minor details of constructon'may be resorted to within the scope of the appended claims, and that I do not wish to limit myself to the specific design and construction here shown.

Having thus described my invention,what I claim and desire to secure by Letters Patent is:

1. A headlight comprising a casing, a source of light in said casing, means coperating therewith adapted to projeeta beam of substantially parallel rays, a concentrating reflector adapted to receive said rays and project the same through a transparent said reflector having means which will project a. `beam o f light .having a vertical focal or crossing line for the projected rays. 4 i

2. A headlight comprising a casing, a. reflector in said casing, said reflector comprising a sectionfof a cone adapted to project a beam'of light having a vertical focal or crossing line for the rays, a transparent aperture in `lhecasing through which said' rays are adapted to be projected, and means 126 within the casinar for projecting a beam of substantially parallel rays against the sectional conical reflector.

3. A headlight'comprising a casing, a re-` Hector havingmeans to project a beam of like aperture in the casing positioned at the approximate crossing line of the rays and means within the casing for projecting a beam of substantially parallel rays against the projecting reflector.

5. A headlight comprising a casing, a reflector in said casing, said reflector comprising a section of a cone adapted to project a beam of light having a vertical focal or crossing line for the rays, a transparent slitliketaperture in the casing positioned at the axis of the cone, said transparent aperture being slightly larger than the area presented at a point drawn through the crossing line ofthe rays, a light in the casing and a parabolic reflector surrounding said light adapted to project a beam of substantiall' parallel rays against the said reflector, sai rays being parallel to the axis of the cone.

6. In a lamp, a housing having a narrow vertical light emitting aperture, a source of light inthe housing, means to reflect the rays from said source of light, and projecting means to re Asive the reflected rays, said last mentioned means being constructed and arranged to project substantially all reiected rays in the form of a wedge shaped beam whose rays cross on a vertical line within the light emitting aperture and continue out therefrom divergently.

7. In a lamp or projector, a housing having a restricted emitting aperture, a source of light within the housing arranged to one Aside of thelight lemitting aperture and concealed from view therethrough,`means to collectlthe rays emanating from the source of light and `p ioject them in the form of parallel rays directed lat an angle tothe 'transverse axis ofthe light emitting aperture, and separate mea'nsvvithin the housing positioned to receive. they parallel rays and constructed and arrangedfto project them out through the aperture' in the form of a beam whose rays .tend in general to converge until reaching the aperture, and thereafter diverge. whereby to illuminate a field of appreciable area;

8. A headlight comprising a casing, a

A,sourcecf light in said casing. a reflector having means. to project a beam of light having a vertical focal or crossingr line for the rays and a transparent aperture in the casing positioned at the approximate crossing line of the' rays, said aperture being just sufiiciently large in area to permit the crossing rays to be projected therethrough.

9. A lamp comprising a casing, a source of light in lsaid casin means coperating therewith to pro'ect aeam of substantially arallel rays, an means to receive the parah el rays and project them out through the casing in the orm of a beam having its rays crossing on a line disposed substantially vertical.

10. A lamp comprising a casing having a narrow vertical aperture, a source of light in the casing, means to project rays of light from the source and a reflector to receive the projected rays and roject them out through the narrow vertical) aperture in the casing, said reflector having a surface generated by revolving a line, the axis of revolution of which is coincident with the axis of the vertical aperture.

11. In a lamp, a source of light, means to project parallel rays therefrom, a reflector constructed to receive the parallel rays and project them in the form of a beam whose rays have a crossing or focal line parallel with the incident rays, said reflectorbeing in the form of a section of the surface of a cone.

12. A lamp comprising a housing, a source of light in the housing, means coperating with the source of light to project a large portion of the raystherefroin in a beam of parallel rays, and means t'o receive the beam and project it outsfrom the housing in the form of a convergent beam whose general direction is angularly disposed with respect to the axis of the incident beam, said second means being of a character to project a beam whose rays will meet and cross, and said housing having a light emitting aperture located where the rays of the convergent beam meetand cross, and restricted in size so as to effectually obscure the contents of the housing.

13. In a amp ahousing havingarestricted light emitting aperture in its front portion, a source of light in the bottom of the housing, a reflector surrounding the source of light, a second reflector near the top and rear of the housing to receive the rays from the first reflector. said second reflector being shaped and positiohed to project a converging beam whose rays will meet and cross within the restricted aperture and continue out divergently.

14. In a headlight, a housing having a slit-like aperture in its front portion for the emission of light. a source of light in the housing, means within the housing coperating with thc source of light to projects. beam of parallel rays. and means tc receive the para lel rays and project them in the form offa beam whose rays meet and cross within the slitlike aperture and continue out in the form of a wedgeshaped beam.

15. A'headliglit comprising a casing, a reflector cage secured within said casing, a parabolic reflector secured in the lower end of said ca re, .i source of light in said parabolic reflector, a projecting reflector pivotally mounted in the cage above the parabolic reflector, a transparent opening in the casing, manually operated means for Swinging t .e projecting reflector in its pivotal mounting, and means carried by the projecting reflector for normally maintaining 1t in a predetermined position` 16.,A headlight comprising a casing, a rellector cage secured lwithin said casing, a parabolic reflector secured in the lower end of said cage, a source of light in said parabolic reflector, a projecting reflector pivotally mounted in the cage above the parabolic reflector, a transparent openin in the cas ing, manually operated means or swinging the pro'ecting reflector in its pivotal mounting, an means carried by the projecting reflector for normally maintaining it in a predetermined position, said means comprising an arm movable in unison with the reflector, a friction shoe en ageable with said arm and a notch former in the arm with which the shoe is adapted to engage to normall retain the reflector in a predetermined position.

4In testimony whereof l .have hereunto set my hand in the presence of two subscribing witnesses.

WILLIAM G. WOOD.

Witnesses:

JOHN H. Hmmmo, W. W`Hmmrp