US2418131A - Lighting fixture - Google Patents

Description

AprEE I, 194?". MARGQLIS I 2,418,131

LIGHTING FIXTURE Filed July 15. 1944 Patented Apr. 1, 1947 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G.'757) 2 Claims.

The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

The invention relates to a lighting fixture of the type having an inverted bowl reflector and a silver bowl lamp. Forming a. part of the fixture is an auxiliary reflector, designed to reflect a portion of the light toward the ceiling.

For the purpose of lighting hallways and large rooms, the use of indirect lighting has been largely superseded by the inverted bowl reflector with a silver bowl light bulb. It was a fault of indirect lighting that insuflicient illumination of the floor and details of the side-wall, such as room numbers, name cards, etc., resulted, and sufficient light for desk work was seldom provid ed. Furthermore, if the ceiling became darkened with dust and soot the general level of illumination was seriously reduced.

The inverted bowl reflector, as employed with a silver bowl lamp, produces a highly desirable form of illumination, since the silver bowl of the lamp prevents glare from the direct rays of the lamp and the bowl reflector catches and deflects the rays from the lamp in a desirable pattern for effective illumination of all the lower portion of the room or hall. There is difiiculty in securing satisfactory illumination of the ceiling when only an inverted bowl reflector is used. A certain amount of ceiling illumination is desirable, both to improve the genera1 i1lumination of the room and to avoid an unpleasant dark shadow on the ceiling above each suspended light. This problem has not been solved with the inverted bowl reflector and silver bowl lamp fixtures employed at present. Similar types of units now available on the market produce too high surface brightness on the reflecting surface causing objectionable glare and eye fatigue. Also these units provide no means of lighting the ceiling, thus creating too great a contrast. This invention is so designed as to have low surface brightness on the main reflector and is provided with an auxiliary reflector of opaque material to light up the ceiling.

It is an object of this invention to provide a new reflecting fixture of the inverted bowl reflector and silver bowl lamp type which insures a satisfactory mounting for the reflector on the lamp bulb support and provides a better configuration of reflector and an effective positioning of the reflector with respect to the lamp.

It is a further object of the invention to provide a lighting fixture of the inverted bowl reflector and silver bowl lamp type having an auxiliary reflector attached to the lower rim of the bowl for lighting the ceiling adjacent to the fixture.

It is a further object of the invention to provide a lighting fixture which avoids the disadvantages inherent in the indirect lighting fixtures still employed in many public buildings, and which combines the advantages of good ceiling illumination with the advantages of the inverted bowl type of reflector.

It is a further object of this invention to design a lighting unit of high efliciency having low surface brightness and being free of objectionable glare.

Further objects of the invention will be apparent from a consideration of the detailed description of the invention, taken in connection with the accompanying drawing in which:

Figure l is a top plan view of the lighting fiX- ture, showing the auxiliary reflector attached to the inverted bowl reflector;

Figure 2 is a side view of the lighting fixture partly in elevation and partly in section.

Figure 3 is a fragmentary side view of a portion of the two reflectors in slightly separated relation.

As shown in the drawing, the invention utilizes a silver bowl electric lamp Hi, which should be of large size, 360 watts or more, for use in oi flces and public buildings. The light it is sup-- ported at the end of a dependin pipe I I by means of the usual socket 12, over which a husk i3 is supported in inverted relation. The husk 13 extends slightly below the juncture of the lamp with the socket, and is provided ordinarily with bayonet slots to support a shade or reflector. The parts required for this assembly are,

% to hi y /8 ball alisner Canopy Stem Husk

Mogul porcelain screw base socket 300 watt silver bowl lamp The main reflector comprises an inverted bowl lit, formed preferably of spun metal or plastic and having a suitable flat white reflecting surface, which may be a baked matte finish. The main part of the reflector M is a smoothly curving bowl of the configuration shown, which effects an even distribution of the light over the area to be lighted. The center of the reflector is formed with a smoothly curved, downwardly depending portion I5, slightly longer than half the depth of the reflector and having an opening at its lower end to receive the husk I3 of the suspended lamp. Means such as headed bolts 16 are provided on the conical projection is to engage in the bayonet slots of the husk l3 to support the'reflector 44 on the lamp fixture.

The lamp bulb is silvered over the lower portion H, as shown in the drawing, and the lower edge I8 of the bowl reflector terminates in the plane of the top of the silvered reflector area I! of the lamp. The top of the reflector 14 is preferably of a height to reach the top of the lamp socket 12.

The auxiliary reflector 19 comprises a smoothly curving ring or annular member having the same reflecting structure as the bowl reflector. It is supported from the lower rim of the bowl reflector It by means of chains 20 secured in apertures 2! in the rim of the bowl reflector l4 and to bracket members 22 on the reflecting face of the auxiliary reflector. The auxiliary reflector I9 is thus supported in spaced relation to the bowl reflector M, with its lower edge 23 almost directly below the rim of the bowl reflector and approximately even with the lower tip 24 of the lamp l6 and its upper edge 25 outside of but in the same horizontal plane as, the lower edge of the bowl Hi.

The outside diameter of the bowl reflector would ordinarily be about 23", and the outside diameter of the auxiliary reflector about 30".

There is thus provided a means for deflecting part of the rays from the lamp upwardly through th space between the two reflectors. This provides a satisfactory illumination of the ceiling above the lamp without materially lessening the lower area illumination provided by the inverted bowl. The reflector is designed in such a way as to be almost radial in design, and thus light striking it will give an even brightness. By referring to the drawing, it will be noted that beam A strikes reflector l4 and is reflected down in a general difiusing manner. Beam B is redirected down and at an angle. Beam C strikin the side of reflector I4 is directed at nearly a horizontal angle, affording wide distribution to the light from the unit. All the light striking the auxiliary reflector I9 is diffused light from the reflector l4 and from the neck of the silver bowl lamp 19. The reflector I9 is so designed as to light the ceiling at approximately an even intensity. It will be noted that none of the principal beams of the source are used for this purpose, but all of the principal beams are utilized for the reflector I l.

It will be seen, that in the use of a fixture of this type no rays coming directly from the lamp can reach the eyes of persons occupying or passing through the areas lighted thereby. At the same time, the light is reflected in an even pattern from the various inner surfaces of the bowl reflector to produce a brilliant light, but one that is diffused to such an extent that are is avoided. It will be observed that the unit is highly efficient, as all of the useful light from the source reaches the main reflector, which in turn redirects it to the plane of utilization. Since this is a direct lighting fixture, and the main reflector curves down, the maintenance will be '4 very low. Also, the auxiliary reflector is shielded against direct light rays from the bulb by means of the silvered reflector means associated with the bulb, and thus receives its light only from spill and diffusion, thus not lowering the efficiency of the main reflector by intercepting the light that would normally reach it. The auxiliary reflector provides for illumination of the ceiling to an extent sufficient to avoid shadow and also to complete the general pattern of illumination by reflection from the ceiling.

While I have illustrated and described the preferred embodiment of my invention, it is to be understood that I do not limit myself to the precise construction herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

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

1. A lighting fixture comprising an annular reflector concave downwardly in cross section,- a light socket, means for supporting said reflector on the light socket, an upwardly flaring annular auxiliary reflector of opaque material having its lower rim substantially the same size as the lower rim of said first-mentioned reflector, means for supporting said auxiliary reflector beneath the first-mentioned reflector with the upper rim of the second-mentioned reflector in the horizontal plane of the lower rim of said first-mentioned reflector and outwardly thereof, and a silver bowl lamp bulb in said socket, the silvered area of the bulb lying within the horizontal planes defined by the rims of the second-mentioned reflector;

2. A lighting fixture comprising an annular reflector concave downwardly in crosssection, a light socket, a lamp bulb in said socket, means for supporting said reflector on the light socket, an upwardly flaring annular auxiliary reflector of opaque material having its lower rim substantially the same size as the lower rim of said firstmentioned reflector, means supporting said auxiliary reflector from and beneath the first-men tioned reflector with the upper rim of the secondmentioned reflector substantially in the horizons tal plane of the lower rim of said first-mentioned reflector and outwardly thereof, and a reflector surrounding the lower portion of the lamp bulb, the area of said last-mentioned reflector lying within the horizontal planes defined by the rims of the second-mentioned reflector.

LOUIS MARGOLIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Baumgartner Jan. 10, 1939

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