US1262570A - Lighting-fixture. - Google Patents

Description

T. w. RO LPH. I LIGHTING FIXTURE. APPLICATION FILED JU LY l7, 19H.

Patenfed Apr. 9. 1918.

FIG. 1

I fly YENTUH WITNESSES.

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THOMAS W. ROLPH, OF CLEVELAND, OHIO, ASSIGNOB. TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

LIGHTING-FIXTURE.

Application filed July 17, 1914.

are suitable for outdoor or other lighting in which the light. is distributed over a comparatively wide area. My invention is particularly applicable for use in connection with light sources of a more or less concentrated nature. such as concentrated filament incandescent lamps of high efficiency. The

'object of my invention is to produce a device which will shield an observer as much as possible from the direct rays from the light source,

ciency of the fixture as a whole.

According to my invention, I provide a shield consisting of a substantially circular band which isspaced from the lamp bulb or other holder for the light source. This shield is non-transparent, being preferably opaque, although it may be somewhat translucent- Its depth will depend upon its proximity to the light source. An important object of the invention is to shield the eyes of the observer from those rays which are ordinarily directed in a horizontal or substantially horizontal direction. When the lamp is Viewed from a distance these rays cause serious annoyance to an observer, especially when the light source is very powerful. It will be apparent that the closer the shield is to the light source the less should be its depth, on account of the greater number of rays which will be intercepted by it. The shield is disposed opposite to the light source, being preferably so placed that a horizontal plane passing through the center of the light sourc will substantially bisect it. In other words, the shield should be in substantial horizontal alinement with the light source; It is preferable that the shield be of such contour that it will reflect downward the rays it. intercepts and, to this end, it is also referable that the inner surface of the shie d have good reflecting properties, which may be secured by making it of a light color.

Specification of Letters Patent.

and which at the same timewill not interfere substantially with the eiii- Patented Apr. 9, 191 8.

Serial No. 851,499.

My invention will be more clearly understood by referring to the accompanying drawing, in which Figure 1 is an elevation, partly in section, 011 an enlarged scale, of a shield comprising my invention, and Fig. 2 is an elevation, partly in section, of a complete fixture, including the said shield.

In the drawing, 10 is a shield or band composed preferably of metal 01' other opaque material. The inner surface of the said shield is preferably of a light color, such as white, which will give it good reflecting properties. The shield 10 is supported by means of thin straps 11 connected to an upper ring 12. As shown in Fig. 2, the shield is supported by a suitable removable attachment 13 to an insulating cap 14 forming part of an outdoor fixture. It is to be understood, however, that this is only one exampleof the use to which my invention may be put, and that it may be applied tp any of the well-known fixture supporting means. As shown in the drawing, my invention is used in connection with an electric incandescent lamp 15, such as that described in Langmuir application, Serial No. 762,327, filed April 19, 1913, and having a concentrated metal filament 16. The shield 10 should be opposite to or, more exactly, should be in substantial horizontal alinement with the light source 16. When used with a lamp such as that shown in the drawing, good results have been obtained with a shield approximately ten inches in diameter and having a depth of approximately two inches. The vertical curvature of the shield 10 is preferably such that it will direct downwardly the rays received from the light source 16. Mounted above the shield 10 and preferably held by the removable attachment 13 .i s When used in connection with outdoor and similar lighting this reflector should'be of such shape that a wide .distribution of the light received by it will be obtained. Preferably. it is of metal and the inner surface is of a light color.

It will be apparent, from-the above derefiector 17.

scription, that theshield 10 will serve to tially horizontal rays sent out from the light source are those which cause the most nnoyance, because they can be seen from a great distance. The other rays are not encountered unless the observer looks upward at the light source. It will also be apparent that the efiiciency of the fixture is not substantially afi'ected. The supports for the shield 10 are of such a nature that they'furnish a very slight obstruction to rays from On the other hand, the

the light source. fact that the shield directs downwardly the substantially horizontal rays intercepted by it adds somewhat to the efiiciency of the fixture.

Various changes and modifications of the above described apparatus Will readily occur to those skilled in the art and are to be considered as coming within the scope of my invention.

lVhat I claim as new and desire to secure by Letters Patent of the United States, is

1. In a lighting fixture, the combination of a concentrated light source and a narrow non-transparent band surrounding said light source, said band being of such dimensions and so disposed as to intercept only the substantially horizontal light rays emitted from said source.

2. In a street lighting fixture, the combination of a concentrated light source and a non-transparent band surrounding saidlight source, said band being of such dimenslons andso disposed as to intercept only the substantially horizontal rays emitted tially horizontal rays emitted from said light source, and areflector mounted above said light source. I

4. In a lighting fixture, the combination of a concentrated light source, a non-transparent band surrounding said light source,

. said band being of such dimensions and so disposed as to intercept only the substantially horizontal rays emitted from said light source, a reflector mounted above said light source, and straps connecting said re flector with said band.

5. In an outdoor lighting fixture, the com bination with a concentrated light source and a reflector of a non-transparent band to intercept only the substantially horizontal rays emitted from the said light source.

In witness whereof, I have hereunto set .my hand this 15th day of July, 1914. If

THOMAS W. RoLrH.

Witnesses:

J. E. KEWLEY, J. H. ANDERSON.

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