US2321008A - Blackout lamp - Google Patents

Description

BLVACKOUT LAMP Fil ed June 5, 1942 Elm v: rvbo'b Dun-1E1 Euntmr an um I Patented June 8, 1943 UNITED STATES rem OFFlC (Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention pertains to a lamp, and more particularly to a lamp for use during nocturnal blackouts.

Air raids have become an increasing menace and as a result have necessitated periods of total or near-total darkness termed blackouts. Since light often must be employed in certain areas, it is imperative that every effort be exerted to confine it to a particular restricted region so as to illuminate as little space as possible. Since light emanating from a source scatters in all directions, an expedient way to avoid some of the danger in connection with an illuminated light source is to prevent the rays from spreading outwardly.

It is therefore an object of this invention to provide a container for a light source which prevents the scattering of light.

A further object of the invention is to provide a housing for a light source which is capable of directing non-spreading rays in a plurality of predetermined directions.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

Fig. 1 is a perspective view, with parts broken away and the shutters removed, of a preferred embodiment of the invention,

Fig. 2 is a view in side elevation of the lamp housing,

Fig. 3 is a similar view with the shutters tilted in a different direction, and

Fig. 4 is a sectional view on the line 4-4 of Fig. 2.

Referring to Fig. 1 there is shown a lamp bulb l screwed into a conventional socket II which may be fastened to a Wall or ceiling (not shown) by suitable fasteners such as screws l2. The socket is enveloped by a holder l3 which is positioned between the base of the socket and the ceiling and held thereto by the aforementioned screws. Telescoped into the holder l3 and fastened thereto by a plurality of clamping screws l4 of a well known type is a cylindrical container l5 which virtually encloses the bulb ID. A box-like housing I6 is welded or suitably bonded in lightproof relationship to the bottom of the container [5. This housing is preferably rectangular in section so as to facilitate the attachment of a plurality of spaced, parallel slats or louvers I! which are nested in and bonded to the open end of the housing Hi.

The lower ends of the louvers I! are preferably, but not necessarily tapered. The tapered configuration makes possible the use of shutters l8 which are secured to the two outer slats by pivot pins l9 as shown in Figs. 2 and 4. These pins permit tlie shutters Hi to be disposed parallel to the side walls of the housing l6 as in Fig. 2 or to be tilted at an angle thereto as represented in Fig. 3.

Light rays emanating from the bulb l0 enter the housing 16 and pass downwardly between the louvers l1. These louvers confine the light in a path parallel to the plane of the slats thereby directing the light rays so that they follow a definite path. The effect is as though the light rays were focused thereby avoiding the scattering effect which occurs when light ordinarily emanates from a source. If desired the louvers may be coated with material to provide non-reflective surfaces thereby increasing the effectiveness of the device. As a result the light is concentrated in a desired area and does not spread to other regions where it might act as a guide beacon to the enemy.

The position of the shutters in Fig. 2, allows the light rays to pass downwardly and also assists in keeping the rays near the shutters from spreading laterally. When the shutters are tilted as in Fig. 3, parallel light rays are reflected upwardly through the open sides of the louvers and toward the ceiling. Thus the shutters assist in directing the light in two generally opposite directions.

While a plurality of parallel slats have been illustrated, it will be apparent that a grill arrangement may be employed in lieu thereof with satisfactory results. Numerous modifications of the structure will suggest themselves to one skilled in the art whereby the device may be adapted for use as a portable light, a street or signal light, for screw attachment into a standard socket outlet, or for other similar purposes.

I claim:

1. In a lamp, a container for a light source, said container having a light aperture, parallel louvers in said aperture extending substantially perpendicular to the plane of the aperture, said louvers having converging plan profiles on their external ends, and a pair of shutters pivotally mounted on the lamp for motion about an axis perpendicular to the louvers and swingable into covering relationship with the converging portion of said louvers for directing light at will in a plurality of directions.

2. In a lamp, a housing for a light source, said housing including a light aperture, spaced parallel plates in said aperture and projecting therefrom said plates having converging plan profiles coming to an apex, and a pair of shutters pivoted to the outer of said plates adjacent the sloping ends, said shutters arranged in a plane substantially perpendicular to the plane of the plates for swinging motion into covering relationship with the converging portions of said plates.

3. A blackout lamp comprising, a housing for a light source, said housing including a light aperture, spaced parallel plates secured to said, housing and projecting from said aperture, said plates having converging plan profiles, and a pair of U-shaped shutters pivoted to the outer pair of said plates adjacent their sloping ends for swinging motion into covering relationship with the converging portions of said plates.

4. A blackout lamp comprising, a container for a light source, said container including a light aperture, spaced parallel plates secured to said container and projecting from said aperture, said plates having edges parallel to the wall of said container adjacent the aperture and extending out from said aperture, said plates including converging portions in plan profile beyond said edges, and a pair of shutters pivotally mounted on the outermost pair of the plates adjacent the tapered portions and arranged in a plane substantially perpendicular to the plane of said plates whereby the shutters are adapted to be selectively operated' to direct light in a plurality of directions and to cover the converging portions of said plates.

DANIEL CANTOR.

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