US 1421506 A
Description (OCR text may contain errors)
A. S. LIMPERT.
HEADLIGHT- APPLICATION FILED JULY 11, 1920.
Patented July 4,
UNITED STATES PATENT OFFICE.
ALEXANDER S. LIMPERT, OF PITTSBURGH, PENNSYLVANIA.
Application filed July 17,
T 0 all whomz't may concern:
Be 1t known that I, ALEXANDER S. LIM- PERT, a citizen of the United States, residing at Pittsburgh in the county of Allegheny.
hereinafter fully described.
It is highly desirable in lights of this character and particularly in automobile lights that the light rays be directed upon the road in front of the machine for a considerable distance without producing a bright glare, which is confusing to the driver of an approaching machine. and to reduce or obviate this glare as much as possible, it is desirable that the light rays be projected in substantial parallelism below the horizontal plane of the drivers eyes of an approach ing machine. This means, of course. that the rays emanating from the light should not bepermitted to project above the plane of the light itself.
It has heretofore been proposed to secure this result by the employment of parabolic reflectors, which are designed theoretically to reflect and project the rays emanating from the rays of light in parallel paths. With such a reflector. a large proportion of the reflected rays will be projected in parallelism, but the direct or corona rays from the source of light will emanate in diverging paths, producing a direct glare outside the path of the reflected rays, and this direct glare is further intensified in certain spots by the rays reflected from the substantially flat portion of the reflector near its center.
The primary object of my present invention is to provide a light of the character indicated, in which the objectionable direct glare will be entirely eliminated, and from which all of the light rays will be projected in substantial parallelism in the desired direction without diffusion or dispersion outside the desired path or planes of projection.
Another object of my invention is to provide a headlight which will throw a strong,
clear and concentrated light so as to ade- Specification of Letters Patent.
Patented July 4, 1922.
1920. Serial No. 396,895.
quately illuminate the road ahead, but which will not produce an objectionable glare and will not blind or confuse the driver of an approaching car. A further object is to produce a headlight 111 which the source of light is adjustably mounted so that the reflected rays projected from the headlight may be properly focused by adjustment of the position of the source of light relatively to the reflecting surfaces. Still another object is to provide a headlight which will be strong and durable in construction, one which can be manufactured at a reasonable cost, and one which will not be subject to displacement of the parts, and which will not be easily broken or injured.
Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following description when considered in connection with the accompanying drawings.
Referring to the drawings:
Fig. 1 is a side view partially in transyerse section of a headlight embodying my lnvention;
Fig. 2 is a face view thereof with the weather glass removed to more clearly show the arrangement of the reflectors;
Fig. 3 is a perspective view of the headlight, certain parts being shown in section; and
Fig. 4 is a fragmentary diagrammatic view showing a slightly modified form of my invention.
Referring now to the drawings more in detail, reference character 5 indicates generally the frame or back of the headlight, this frame being customarily made of sheet metal and provided with a circumferential flange 6, terminating in a bead 7, shaped to cooperate with suitable means (not shown) for holding the weather glass or lens 8 in position. A disc 9 fitted within the frame substantially at the base of the flange 6 serves to strengthen the structure, and at the same time,afi'ords a support for the nipple 11, in which the lamp socket 12 is carried. This socket is connected with the wires 13 in the usual manner, which extend rearwardly through the frame, which is equipped with the usual protective sleeve or thimble 14.
In order that the lamp 15, which is of usual construction for detachable connection with the socket 12, may be adjusted towardor from the frame 5 for the purpose of focusing the light, the socket 152 is adjustably connected with the nipple ll. l Vhile any preferred method of connection may be utilized, I have shown in the present in stance the nipple 11 as equipped with an inclined slot 16, through which a lug or screw 17 secured to the socket projects. By turning movement of the socket, it is ad justed inwardly or outwardly with respect to the nipple and when the requisite adjustment l'lcS been secured, the socket is locked in adjusted position by means of a set screw 18. It should be noted at this point that the disc 9, instead of pres nting a bright surface having light reflecting properties, is inert, and in the prefe ed construction of my light, is painted black so that no light is reflected therefrom.
The reflection of the light rays ting? from the source of light 15, so th rays will be projected from the headlight in the desired direction in substantial parallelism, is effected by a series narrow frustoconical reflectors 19, arranged concentrically with respect to the lamp base, and disposed in spaced relation from front to rear of the light. the refle tors being from rear to front of progresivd; ishing diameters, so that, as will be apparent from the drawings, the largest reflector is disposed at the rear while the smallest is disposed in front. These reflectors are mounted upon suitable supports 21, preferably three in number. to which they are securely attached by soldering or otherwise, to form a substantial and rigid structure. Preferably, the supports 27 are slotted to-accommodate the inner edges of the reflectors, thus adding to the rigidity of the structure, and the assembled construction i. then secured to the disc 9 in any suitable manner so that it will be retained in position concentrically with the lamp, and will be held against displacement or rattling when in use.
It will be observed from Fig. 1 that the reflectors are arranged in overlapping relation so that when viewed from the inside, the inner edge of each successive reflector from rear to front slightly overlaps the outer edge of the next rearwardly adjacent reflector, and when viewed from the front, the outer edge of each successive reflector from rear to front slightly overlaps the inner edge of the next rearwardly adjacent reflector.
With this construction, it will be manifest that the light rays emanating from the source of light are all intercepted by the reflectors so that no light except on short arc directly in front of the lamp is permitted to escape unreflected between adjacent reflectors. It will also be observed that each successive reflector from rear to front is set at a more acute angle with respect to a transverse plane parallel with the disc 9, these angles being such that the rays when reflected are all projected forwardly in substantial parallel paths, as illustrated in Fig. 1.
Furthermore, it will be observed that as the reflectors approach the front of the headlight, they are disposed progressively nearer together in order to preclude direct emanation of rays between them so that the corona rays heretofore mentioned are cut off and reflected. These reflectors may, if desired, be continued practically to the front of the lamp, a close approach to such arrangement being shown in Fig. l, but since the direct rays in front of the source of light emanate substantially in the desired direction without reflection, the employment of a large number of these very small reflectors does not justify the expense, and in order therefore, to preclude the glare resulting from the rays which are not intercepted by reflectors across a small are at the front of the lamp, I prefer to sandblast or otherwise roughen the front of the weather glass 8 over this area, as indicated by reference character 20. This roughened area will 0b viate the glare, and for all practical pur poses, is substantially as effective and considerably cheaper than the employment of a large number of closely set reflectors of very small diameters.
Since the back of the lamp, or in other words, the disc 9 is inert, it will be manifeet that no rays of light strike the reflectors e :ept those emanating directly from the source of light. Consequently, the location of this source being known and the source itself being capable of adjustment as previously explained, each ray is intercepted and accurately reflected in the desired direction, and no fugitive rays, such as are present in parabolic reflectors as the result of double reflection, are produced in my improved construction, and consequently, no rays are delivered in an undesirable direction, but each ray is accurately projected in the direction that it should travel. Should the lamp be positioned too far forwardly, the light rays will be projected in diverging paths, and should it be too far rearwardly, the rays will be projected in converging paths which will ultimately crOss and then diverge, but by means of the adjustment provided, the lamp can be accurately positioned so that all of the rays will be projected in substantial parallelism and in the desired direction.
It is believed that my invention, one mode of its construction, and many of its inherdescribed are capable of considerable modification, without departing from the essence of the invention as defined in the following claims.
1. An automobile headlight comprising a source of light, a series of concentrically arranged annular reflectors adapted to reflect in substantial parallelism intercepted light rays emanating at various angles from said source, said reflectors being of progressively diminishing diameters from the rear to the front of said headlight and each being respectively disposed at different angles with respect to said source of light and the front reflector being in advance of said light and the rear reflector being behind said light.
2. An automobile headlight comprising a source of light, a series of concentrically arranged annular reflectors adapted to reflect in substantial parallelism intercepted light rays emanating at various angles from said source, said reflectors being of progressively diminishing diameters from the rear to the front of said headlight and each being respectively disposed at different angles with respect to said source of light, the front reflector being in advance of said light and the rear reflector being behind said light and the arrangement and size of said reflectors being such that direct rays cannot be projected by said source to points intermediate the front and rear reflectors Without being reflected forward by one of said reflectors.
3. An automobile headlight comprising a source of light, a series of annular reflectors of progressively diminishing diameters arranged in overlapping relation with respect to each other so that no direct rays from the source of light can pass between adjacent reflectors without being reflected thereby, the front reflector being disposed in advance of said source of light and the rear reflector being disposed behind the rearmost point of said source of light and said reflectors each extending rearwardly a distance less than that of the next adjacent reflector to the rear thereof.
4. A headlight comprising a series of concentrically disposed annular reflectors, a source of light comprising an electric light bulb disposed axially within such series of reflectors, the outermost reflector being in front of said light bulb and the rear reflector being to the rear of said light bulb and said reflectors, when viewed from the front, having the outer edge of each successive reflector from rear to front slightly overlapping the inner edge of the next rearwardly adjacent reflector.
ALEXANDER s. LIMPERT.