US1525196A - Lamp or headlight - Google Patents

Description

H. N. OT

LAMP OR HEADLIGHT 2 Shets-Sheet 1 Filed Aug. 13, 1921 WVE VTwQ? (9% wwm fi ATTORNEYS F b, 3, 1925. 1,525,196 H. N. OTT

LAMP 6R HEADLIGHT Filed Aug. 13, 1921 2 Sheets-Sheet 2 Patented Feb. 3, 1925 I HARVEY N. OTT, OF BUFFALO, NEW YORK.

LAMP OB HEADLIGHT.

' Application filed August 18, 1921. Serial No. 492,094.

To all whom it may concern;

Be it known that I, HARVEY N. O'1'r, a

citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented'a new and useful Improvement in Lamps or Headlights, of which the following is a specification.

This invention relates to improvements in lamps of the kind in which it is desired to control the direction of the rays and the field of illumination. The invention is particularly applicable to automobile headlights, but it is not intended to l1m1t the invention to such use.

The objectof the invention is to produce a lamp of this kind which is so constructed that the rays emanating, from the available source of light and reflected from a substantially parabolic reflector shall pass from the lamp in a beam none of whose rays areinclined upwardly from a line passing through the axis of the reflector to cause glare in the eyes of a pedestrian or dr1ver approaching the vehicle on which the lamp may be placed; and also to improve the construction of lamps of this kind in other respects hereinafter specified.

It is a well-known fact that light emanating from a theoretical light point placed at the focal point of a parabola and impinging upon the reflector will be reflected therefrom as a beam of parallel rays. Rays from a larger source so placed are reflected not only as substantially a beam of parallel rays, but

also as rays diverging from the parallel, the divergence increasing as the points of light in the light source are placed farther from the focal point of the.condenser,the variation from the parallel being more or less uncontrollable.

Inasmuch as the light source must be greater than a theoretical point, and inasmuch as the greatest divergence will be in the plane of the largest dimension of the. light source the lamp is provided with a,

eyes above or below the axis of the reflecton.

As a further precaution against upwardly extending rays a projecting hood or visor extends forwardly from the upper edge of the parabolic portionof the reflector. In

order that this may be most effective thelight source and the axis of the parabola beneath it should be as nearly-as possible in the planeof this visor. This means that the parabolic portion should'be as small as possible with a short focal length so that the light source in its focal point may project light to the reflector in as large an angle as possible to increase the volume of the reflected beam. This means the light source must be close to the apex of the condenser. In order to accomplish this the filament is placed near the end of a small tubular bulb which is used with the base up and which is held and adjusted as hereinafter described.

In the accompanying drawings:

Fig. 1 isa longitudinal central sectional elevation of a lamp embodying the invention.

.Fig. 2 is a fragmentary sectional plan view thereof on line 2-2, Fig. 1.

Figs. 3 and 4 are transverse sectional elevations thereof on lines 33, and 4- 4, Fig. l. i

' Fig. 5 is a bottom plan view thereof. Fig. 6-is a front elevation thereof.

The invention is illustrated in theaccompanying drawings and is-herein described as applied to an automobile headlight. It is, however, not intended to limit the invention to use in connection with automobile headlights since the same may be used for any other purpose where it is desired to control the direction of the, rays of light.

The lamp shown in the accompanying drawings includes an outer housing having an upper rounded or arched wall A which is bent downwardly to form the sides of the housing and a rear wall a. The housing is provided on its upper end with an opening or slot a closed by a suitable hinged cover or the like a whereby access can be had to the interior of the housing. A housing of any other suitable or desired construction may be employed if desired. The, lower portion of the housing is closed by means of a window or glass plate B which is ar- I ranged at an inclination to the horizontal and which is suitably held in place on the 6 extending inwardly from the lower edges of the housing and which engage the lower edges of the window or plate B to hold the same in place." If desired, the window B may be provided with an upwardly extending portion b which, in the construction housing A, preferably by means of flanges shown, extends in front of .a dim light C, this light being of a small candle power and arranged in a reflector c in the upper portion of the lamp. The glass window or plate in the construction shown, is secured in place by sliding the same rearwardly into engagement with the flanges b of the lamp housing and is held in this position by means of a clip 6 secured on the upper wall A of the housing and preventing the window from moving forwardly out of its operative position. All of these parts maybe of any other suitable construction.

The lamp or headlight includes a source of light D suitably held on the frame of the lamp, an electric incandescent lamp being used in the construction shown, which has its filament extending approximately through the focal point of a substantially parabolic reflector or the like E. The glass bulb or housing in which the filament of the lamp is contained is preferably substantially tubular in construction and of small diameter, the bulb being elongated as shown so that the heat from the filament cl can be dissipated from the upper portion of the bulb. A bulb of this construction makes it possible to use a parabolic reflector of short focal length, which is decidedly advantageous for the reason that a reflector of this kind can be made of comparatively small size to take in a large angle of light from the light source and at the same time keep the reflecting area near the forwardly projecting visor, and thus can be made to reflect a larger percentage of the light from the filament into a parallel beam than is practicable with parabolic reflectors of 'greater focal length and of the same area.

The reflector E in the construction shown, is provided near its upper portion with an aperture 6 through which the electric lamp extends and the front edge of the upper portion of the parabolic reflector is flattened into a substantially horizontal portion or visor F, which extends forwardly to the front portion of the headlight. The sides of the flattened portion F are joined by downwardly curved side port-ions f which are substantially parabolic, being continuations of the parabolic curve of the portion E of the reflector. These sides are cut off at an inclination to the horizontal, terminat ing at the plate or window B. The reflector or visor F has the effect of directing any rays of light projected thereon downwardly towards the road and thus prevents rays of light from passing upwardly to produce a glare. In the construction described, the window and reflecting surfaces are so arranged relatively to each other that all of the light rays leaving the lamp in a vertical lane passing through the axis of the para ola which strike a reflecting surface and which emanate from a theoretical light the reflector.

point placed at the focus of the parabola, are thrown out of the lamp with only one reflection. When this condition is fulfilled the reflected rays pass out parallel to themselves and substantially horizontally-no reflected rays passing out upwardly, and a very efficient use is made of the light and a proper operation of the lamp without glare is ensured. By means of the construction shown, all rays of light leavin the lamp emanating from the source of light D will either be reflected only once or else will pass directly through the window without reflection, double reflections being entirely avoided by means of this construction. This arrangement of the reflecting surfaces results in a very efficient use of the available light, so that practically all of the light is projected where it is of most use, and at the same time, all objectionable glare is avoided. By so proportioning the electric lamp that the parabolic reflector may be given a short focal length, the reflector can be made smaller than usual and can extend beyond the vertical plane of the focal point to a considerable degree, and thus reflect much light forwardly onto the road which would otherwise be wasted.

1n lamps of this kind as heretofore made, it has been found practically impossible to control the reflection of the light from the parabolic reflector for the reason that the filaments of electric lamps could not be confined to a single point such as the focal point of a parabola. Consequently. such rays as emanate from points not in the focal point cause the reflector to project the rays of light in various directions, many of the rays passing upwardly and thus producing objectionable glare. Since electric incandes cent lamps are usually used in headlights of this kind, this objection is difficult to overcome since the filament of electric lamps of this kind must have considerable length and is usually arranged in the form of a coil so that rays of light emanating from the filament cannot be confined to the focal point of Such rays as emanate from the filament above or below the focal point cause rays to be reflected upwardly and downwardly, the upwardly projecting rays causing the objectionable glare. In order to largely overcome the objection of having some of the rays projected upwardly, the electric lamp D shown is provided with a filament arranged as nearly as possible in a straight line and extending transversely of the lamp. The electric lamp can then be adjusted so that the filament extends substantially transversely of the lamp through or slightly above the focal point of the reflector. By means of this arrangement the rays of light emanating from those parts of the filament which extend laterally beyond the focal point will be reflected sidewise and thus laterally increase the field illuminated by the lamp. Since only small portions of ment slightly above the focalpoint no rays the headlight.

are projected upwardly, thus the glare is eliminated and at the same time, the field of illumination is extended laterally, which is desirable since it enables the headlight to illuminate a wider portion of the, road. By means of the rearwardly inclined window or lens, the lower portions of the reflector may be cut away as shown and this helps greatly in avoiding glare since the remaining lower part of the reflector will be practically concealed by the visor.

In the particular construction of the lamp shown in the drawings, the reflector F is held in place and protected against injury by means of a shield or protector G corresponding substantially to the shap of the reflector F. This shield and reflector are preferably pressed downwardly against the window or glass by means of set screws h arranged on a bridge member H which is suitably secured to the housing A of the lamp. By tightening the "screws 11., the shield presses the window or glass plate B against the flanges b of the housing so as to avoid rattling and to hold the window in place in the lamp. Other means may be employed for holding the reflector in place in the lamp housing.

Means are preferably provided for adjusting the electric lamp or source of light 1) with reference to the reflecting surfaces of the headlight so that the source of light maybe readily placed into the correct relation to the reflecting surfaces. In the construction shown for this purpose, the "electric lamp D is suitably mounted on an arm of a lever or pivoted light holder I. The electric lamp may be held on the light holder in any desired manner. In the construction shown, the electric lamp is provided at opposite sides with pins or projecting portions 2' which engage corresponding depressions in the bushing suitably held in the pivoted light supporting member I. This construction makes it possible to turn the electric lamp relatively to the light holder in such a manner that the filament may be arranged to extend transversely of The light supporting member I is pivoted at i on a second pivoted member or adjusting lever K which is pivoted at Z: on the bridge member H. The light supporting member I has an arm i against which a spring 2' bears and a set screw 71 extends through a hole in the arm 2' and has a threaded engagement with the pivoted adjusting lever K. The pivoted member K is provided with a set screw in extending through a hole in this pivoted member and engaging a threaded hole in the bridg member H. By means of this arrangement an adjustment of the set screw i will cause the filament of the electric lamp to swing about the pivot i and since this pivot is arranged almost vertically above the filament or source of light, this swinging will cause the filament to move practically longitudinally of the headlight. An adjustment of the set screw causes the electric lamp to swing about the pivot is and this movement of the' filament is substantially in an up and down direction because the pivot is is arrangedat a considerable distance in front of the filament. Conse-, quently, by means of the two adjusting screws the filament may be located in the desired position in the headlight. By means of the arrangement of th spring i which is shown in the drawings, both of the two adjusting screws 7? audit operate against the action of the spring 2", so that only one spring is required.

The electric lam may be held in place in the sleeve or bushing c" in any suitable manner. In the construction shown, the pivoted member I has a-downwardly extending portion Z on which an insulating member L is secured. A current conducting member Z' is mounted on the insulating member L and current'is conducted from this member to one of. the terminals of the lamp by means of a contact member l which is hinged on the current conducting member Z and which is yieldingly pressed into engagement with a terminal of th lamp by means of a springl One of the conductors m is connected to the current carrying member Z of the lamp and another conductor m connects with any portion of the headlight, such, for example, as the pivoted light-supporting member I. Any other means for adjustably supporting the electric lamp on the headlight and for transmitting current to the electric lamp may be employed.

The bridge member H is preferably also employed for holding the small dim light C in place. For this purpose, a lamp carrying rod or plate N is employed on the outer end of which the lamp socket n for the dim light is secured. The lamp-carrying member N has a hooked portion 7:. adapted to enter into a slot 11. in the bridge member H at the end of the slot. The inner end of the lamp carrying member N may be held in place in any desired manner, for example,

by means of a set screw n? adapted to enga e in a threaded hole in the bridge member and extending through a slotn in the lamp carrying member N. The slot n has an en larged portion n through which the head of the set screw n may pass. Consequently if it is desired to remove the dim light together with the lamp carrying member ,it is only necessary to release the set screw a and to draw the extension member rearwardly until the set screw may pass through the enlarged portion n of the slot in the carrying member, this movement of the light vcarrying member also releasin the hook n from engagement with the bri ge member. Other means for mounting the dim light in the headlight may be provided.

The lamp or headlight described has the advantage of accurately projecting the light so that the road may be Well illuminated without producing any objectionable glare. Th constructionof the housing is desirable since. it renders the parts of the lamp readily accessible without necessitating the removal of the window or glass plate.

I claim as my invention 1. In a lamp, the combination of a substantially parabolic reflector, a visor extend-' ing forwardly from the upper portion of said reflector and having a reflecting surface forming substantially a continuation of said reflector, a source of light arranged approximately in the focal point of said reflector, a housing enclosing said reflector and said visor, and extending above said visor, adjusting means for said source of light arranged in said housing above said visor, and an opening in said housing above said visor for rendering said adjusting means accessible.

2. In a lamp, the combination of a substantially parabolic reflector, a visor extending forwardly from the upper portion of said reflector and having a reflecting surface forming substantially a continuation of said reflector, a source of light arranged approximately in the focal point of said reflector, a housing enclosing said reflector and said visor and extending above said visor, and a dim light arranged in said housing above said visor.

3. In a lamp, the combination ,of a substantially parabolic reflector, a visor extending forwardly from the upper rtion of said reflector and having a ret dting surface forming substantially a continuation of said reflector, a source of light arranged approximately in the focal point of said reflector, a housing enclosing said reflector and said visor and extending above said visor, adjusting means for said source of light arranged in said housing above said visor, a dim light arranged in said housing above said visor, and an opening in said housing above said visor for rendering said adjusting means and said dim light accessible.

4. In a headlight, an elongated casing comprising a lower compartment, a lamp at the rear thereof, and an upper compartment, a relatively dim parking light at the front of the same, the lower compartment being open at the bottom and the upper compartment being closed at the top, substantially as set forth.

5. An automobile headlight comprising a casing open at the bottom, a reflector at the rear of the casing, a lamp at the focus of the reflector, a relatively dim lamp above said first lamp and an opaque partition between said dim lamp and said reflector, substantially as set forth. I

HARVEY N. OTT.

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