US1568505A - Nonglare lens and lamp therefor - Google Patents

Description

Jan. 5 1926.

'w. T. FlsHLr-:IGH

NONGLARE LENS AND LAMP THEREFOR 2 Sheets-Sheet l Filed Deo. 16

Jan. 5 l, 1926.`

w. T. FlsHLElGH NONGLARE LENS AND`LAMP THEREFOR m M nl m. f 5 M k r E m INVEN'TOR,

14 TTORNEY.

UML By W l TNESS:

Patented Jan. 5, 1926.

UNITED STATESI WALTER T. FISHLEIGH, OF DETROIT, MICHIGAN.

NONGLARE LENS AND LAMP THEREFOR.

Application led December 16, 1921. Serial No. 522,773.

To all whomz't may concern Be it known that I. IVALTER T. FISHLEIGH, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented new and useful Improvements in Nonglare Lenses and Lamps Therefor, of which the following is a specification.

The object of my invention is to provide new and useful vehicle lamps and lenses therefor of simple, durable, and inexpensive construction.

A further object of my invention is to provide a lens for headhghts which are adapted to meet the requirements of driving after dark and at the same time to comply with the various laws and regulations with regard to such lamps.

A further object of my invention is to provide a vehicle lamp and non-glare lens therefor which is arranged to refract the rays emanating from an ordinary headlamp in such a manner that the light from the lamp will be concentrated at certain points, will be somewhat diffused at other places, and will be still further diffusedat still other places.

A further object Vof my invention is to provide a lens designed to refract the rays from a headlamp so that the beam has portions of varying intensity thereby not only adapting it for the drivers convenience but also making it comply with all the regulations with regard to such lamps.

A further object of my invention is to provide such a lens -that the requirements or regulations will be exceeded by a large amount where the regulations set a minimum candle power, and which will be substantially less where the regulations set a maximum allowed candle power.

A further object of my invention is to provide a lens which is especially adapted for hcadlamps having bulbs or lights therein which can be focused relative to the reflector and having mounting means sov arranged that the lamp itself may be tilted.

A further object of my invention is to provide with such a tilted lamp having means for focusing it, a lens having as its main characteristic devices for refracting the rays of the beam laterally, and in combination with this characteristic, means for varying the lateral refraction and means for refracting vertically a portion of the beam to divert that portion in agiven direction.

lVith these and other objects in view, my invention consists in the arrangement, combmation, and construction of the various parts of my improved device, as described in the specification, claimed in my claims, and shown in the accompanying drawings, in which:

Figure 1 shows my improved lens in elevation.

Figure 2 shows a top or plan view thereof.

Figure 8 shows a side elevation thereof.

Figures 4, 5, and 6 are diagrammatic views illustrating the features of my lens whereby the combined result thereof is a useful beam, and

Figure .7 illustrates a screen illustrating the results of the use of my improved lamp by showing diagrammatically the beam thrown upon such a screen.

Figure 8 of the drawings represents a view with the light support bent or inclined so as Vto direct the lights rays downwardly from the horizontal.

Referring to Figure 1, it will be seen that my lens is composed of transparent glass having a raised portion 10 at one side thereof in which are formed a series of vertical flutes 11. These flutes are arranged in three contiguous sets or series, the outer two sets being appreciabl deeper, as illustrated at l2, than are the utes of the central set or series illustrated at 13. At'the bottom of the lamp and on the face opposite the raised portion 10, I provide a horizontal prism member 14 with a comparatively slight angle of inclination.

Around the raised portion l0 is a flange 15 having squared or straight portions 16 thereon. At some place on the lens I place indicating characters 17 designed to indicate which is the top and frontl of the lamp, this indicating character taking, if desired, the form of the name of the maker of the lens, and formed in raised letters or in any other suitable manner in or on the glass. i

This lens, as has been previously noted, has comparatively shallow central vertical flutes 13 which spread the light passing therethru to a distance of approximately 12 feet, and it may be mentioned that the portion of light passing thru these central flutes is very large as compared with the amount of light passing thru the remaining portion of the. lens. By reason of these flutes, therefore, which are illustrated diagrammatically in Figure 4, I spread the porwith a comparatively small spread and comparatively great brilliance thereby placing the bright light from the lamp just where it is most needed. v

Th@ series of flutes at the sides ofthe lens and at either side of the tintes 13 are relatively deeper and are designed to give a spread ot' approximately thirty-tive feet. t will be noted that these iiutes are not quite as high due to the circular shape of the lens, as are the central utes 13, so that the beam projected thru these tlutings is not as high and is spread laterally a considerable distance. The image on the screen secured by these flutes 12 is illustrated in Figure 5. This broad shallow beam of light secured by theseutes is highly desirable for any vehicle as it gives very Wide spread to illuminate not only the road ahead but also the objects at either side of the road thereby giving warning of curves or other objects at the side of the road which are of interest to the driver of a vehicle. Objects, however, which are at the side of the road do not require as strong illumination as do those directly ahead of the vehicle and it will be noted that the image as shown in Figure 6 is of somewhat less intensity than fthat shown in Figure 4, which is secured from the central tintes 13.

It has been found desirable by experience :to arrange the beam from a vehicle head-` lampv so that the brightest part of it is slightly above the road at a distance of approximately one hundred feet from the vehicle and approximately at the center line of the vehicle. As the central portion of the beam secured from any lamp with which I am familiar is the strongest part, the lamp, in lorder to secure the result named, must therefore be focused on a Ivertical line passing thru the point M, and on a horizontal line passing thru the pointM, or a point not greatly below the point M on a vertical line passing therethru. `With this focus, however, which is necessary as just stated, it is difticult to illuminate the,road near to the `vehicle as the light from the lamp by this focus does not touch the road until it has travelled a considerable distance from the vehicle.- It is desirable notonly to have the road -near the front of the vehicle illuminated but also to have the illumination mentioned, of) considerable spread.

is has been heretofore noted, there is a horizontal prism 14 on the outer face of the lens member which l have provided and this horizontal prism tends to retract the rays passing therethru downwardly toward the road. it also spreads or widens the beam at points closer to the car or vehicle for the reason that it bends down a portion of the wider part of the beam on to the roadI closer to the vehicle thereby giving a relatively `wide road illumination comparatively close to the vehicle.

This portion of the beam which is deflected or retracted downwardly by the prism 1l is of relatively less intensity than the major portion ot' the balance o1c the beam so that this deflected portion of the beam, the image oi which is illustrated in Figure 6, is of relatively less intensity than the major portion of the balance of the beam. I consider this quite an important feature of my invention for the reason that the -intensity 'of light varies inversely as the square of the distance from this source, so that the comparatively weak portion of the beam which is defiected down to the roadway nearer the car illuminates the'road near the vehicle with substantially the same intensitI as the stronger portion of the beam illum1 nates the road at a greater distance from the vehicle.

evenly illuminated'area extending from a point slightly in front of a vehicle to a p oint a considerable distance from the vehicle. This feature of the light secured makes'it easier for the vehicle operator to catalog in his mind any part or obstruction in the road when it first becomes visible instead of making it necessary to glance at such object or part several times as the vehicle approaches in order to make sure that the first impres-4 sion of the object or part Was correct.

In Figure 7 I have showna screen havin the points C, D, M, P, and Q, illustrated thereon together with a diagrammaticillustration ofthe images produced on this screen relative to these points bythe various portions of my improved lens. For instancethe image illustrated by the lines 18 is the same as that 'illustrated in Figure 6; the image illustrated by the lines 19 that et Figure 5; and the image illustrated by the lines 20 that of Figure 4. rl`he portions within these images have been shaded with lines varying in distance from eachother to illustrate the varying light intensityl of the various parts of these images and thebeam.

For instancethe points M andP both right.

the vehicle, do not require so great a lightx but receive light from both the prism portion 14 and the shallow tintes 12. The por- The beam produced from my iml proved lens produces an impression ofan tion of the image 18 near the beam 21 thereof is the portion of the beam which falls upon the road close to the vehicle and it will be noted that this is of relatively less in- `tensity, as has heretofore been stated, for

the purpose of making the illumination for a considerable distance in front of the vehicleuniform in appearance. It will be noted that these various images are spaced a considerable distance from the point C which is the glare point directly in front of a vehicle, and they are spaced still further from the point D which is the glare point determined to be the average position of the eyes of an approaching vehicle operator. These points C and D are, therefore, not illuminated so that there is no glare at. these points. In this connection, however, it should be explained that the images which are here diagrammatically Villustrated are not sharply outlined or always perfectlyregular in outline, altho they all conform substantially' to the showing here made, the slight irregularities being due to imperfections in the glass of the lens or the placing of the filament in the bulb and in the reflector. There are also a large number of accidental rays from the beam of any ordinary lamp so that as a matter of fact there is a considerable amount of diused light surrounding each of these relatively sharp images.

The forwardly projecting portion of the prism 14 over-hangs the bottom of the re' taining ring which holds the lens, thereby forming a water-shed which assists in preventing moisture from the face of the lens from running into the space between the lens and the retaining ring. It may also be mentioned that my improved lens is so efficient, from the structure used, that it may be formed by casting in molds without materially affecting itsusefulness or the results secured thereby. I consider this a very important point in connection with the use of a lens, as the difference between the cost of grinding a lens and of casting it is very large, so that a lens which may be cast has a very great advantage in price over a lens which must be ground in order to be efficient.

In installing the lens in a vehicle lamp it will be understood that the vehicle is first preferably moved to a place where it will be level and will face a screen similar to that illustrated in the drawings which is placed one hundred feet distant vfrom the vehicle lamps. The light may then be focused by moving the incandescent bulbs therein along the axis of the lamp until the image on the screen is as small as possible and the center of the image is substantially below the point M. The positioning of the focus may be accomplished by aiming the beam by varying the positionof the'lamp on the vehicle as, for instance, by bending -the lamp brackets to cause the beam to strike the screen at the proper place. when the axis of the car is perpendicular to the center of the screen. The lens may then be installed in the lamp or lainpswith the indicating character 17 at the front and top. It yvill be understood, of course, that this'indlcating character may be placed 1n some other position and the instructions correspondingly varied. The lens should be clamped in this position, that is where the flutes'12 and 13 are vertical, by any suitable means, as for 'instance by lugs engaging the flattened portion 16 of the clamping edge 15. Other methods may be used, of course, for main- A stantially similar to that illustrated in Figure 9. The lamps should, of course, be so arranged and secured that their position will not change after they have once been properly focused and set.

Other changes may be made in the arrangement and construction of theV various parts of my improved device without departing from the spirit of the invention vtherein and it is my intention to cover by my claims such other changes as may be reasonably included within the scope thereof.

I claim as my invention:

1. A lens of the character described having a series of vertical ribs disposed in vertical zones with the ribs of the center zonev having a curvature different from the ribs on the side zones extending thereacross, and a single horizontal rib extending across said lens near only one edge thereof.

2. A lens for a vehicle headlight having a reflector and a light source at its focus, comprising a plurality of vertical zones on one face thereof, each zone comprising a plurality of vertical cylindrical flutes, the curvature of each flute in thefcentral zone being shallow to project a centralconcentrated and slightly spread beam of light, the curvature of each flute of the outer zones being deeper than that of the flutes of the central zone to greatly spread the light laterally, and a single horizontal prism at the bottom of the other face of the lens to slightly depress a portion of the light downwardly to illuminate 4the path in front of the vehicle.

3. A lens for a vehicle headlight having a reflector and a light source at its focus, said lens being provided with a plurality of vertical zones on one face only thereof, each zone comprising a series of parallel vertical flutes, the flutes of the central zone being of a different curvature from the flutes of the outer zones, and a single horizontal prism at the bottom of said lens to depress a portion of the light downwardly to illuminate the path immediately in front of the vehicle.

4l. A lens for a Vehicle headlight having a reflector and a light source at its focus, comprising a plurality of vertical zones on one face thereof, each Zone comprising a plurality of vertical cylindrical flutes, the curvature of each flute in the central zone being constructed to project a central concentrated and slightl7 spread beam of light,

each flute of the outer zones being con- 10 structed to spread light rays laterally, and a single horizontal prism at the bottom of the lens to depress a portion of the light downwardly to illuminate the path in front of the vehicle. i

Dated: Dec. 9, 1921.

WALTER r. rrsHLEGH.

Images