U.S. patent number 3,697,740 [Application Number 04/883,965] was granted by the patent office on 1972-10-10 for area lighting luminaire.
This patent grant is currently assigned to Westinghouse Electric Corporation. Invention is credited to Melvin R. Anderson, Charles P. Breed.
United States Patent |
3,697,740 |
Breed , et al. |
October 10, 1972 |
AREA LIGHTING LUMINAIRE
Abstract
An area lighting luminaire which includes a base having a lamp
socket and lamp mounted thereon and extending above the base. The
lamp and lamp socket are surrounded by a light distributing housing
which includes a cylindrical fresnel lens surrounded by a plurality
of stacked annular louvers spaced one from the other and extending
radially and downwardly to shield the lens and lamp from view at
viewing angles of horizontal and above. A cover member closes off
the top of the light distributing housing and may include a central
lens portion for the vertical release of light.
Inventors: |
Breed; Charles P. (Alexandria,
VA), Anderson; Melvin R. (Avon Lake, OH) |
Assignee: |
Westinghouse Electric
Corporation (Pittsburgh, PA)
|
Family
ID: |
25383681 |
Appl.
No.: |
04/883,965 |
Filed: |
December 10, 1969 |
Current U.S.
Class: |
362/257 |
Current CPC
Class: |
F21S
8/088 (20130101); F21V 11/02 (20130101) |
Current International
Class: |
F21S
8/08 (20060101); F21v 011/02 (); F21v 013/04 () |
Field of
Search: |
;240/46.31,46.37,46.41,46.43,92,93,103,104,106.1,108,109,46.01,46.33,46.39,78LK |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Queisser; Richard C.
Assistant Examiner: Snee, III; C. E.
Claims
What is claimed is:
1. An area lighting luminaire comprising:
a base including means for mounting a lamp socket and lamp
therein;
a cylindrical lens defining a lamp cavity positioned above said
base and arranged to surround said lamp and at least a portion of
said lamp socket;
a plurality of annular louver members surrounding said cylindrical
lens and stacked one above the other;
spacer means separating each of said annular louver members from
its adjacent louver member, said annular louver members including
an annular ring portion and a radially and downwardly extending
louver portion, said spacer means separating each of said louver
members from its adjacent louver member a distance such that the
downwardly extending outer end of each louver portion lies in
substantially the same plane as the ring portion of its adjacent
lower louver member, the top and bottom annular louver members
including inwardly directed flanges serving to mount said
cylindrical lens therebetween; and
a cover member overlying said lamp cavity, the upper edge of said
cylindrical lens and at least a portion of the uppermost louver,
said cover member including a central disc-shaped lens portion
overlying the cavity defined by said cylindrical lens.
Description
BACKGROUND OF THE INVENTION
This invention relates to area lighting luminaires and more
particularly to a low level lighting fixture which distributes the
light emanating therefrom toward the ground for lighting walkways
and streets of a residential or commercial nature.
In the past, area lighting luminaires have generally included a
visible refractor or lens and had associated therewith a degree of
glare at least when interposed in a person's line of vision.
Generally, the light source itself could not be seen in these
fixtures but at least the location of that light source was quite
apparent to the viewer. These dots of brightness along a walkway or
roadway, when lit, were the principal attention attractor. Area
lighting fixtures are of course employed for the purpose of
illuminating objects or areas and in many modern applications are
primarily employed to direct attention to the objects or areas so
illuminated. The present day area lighting luminaires, because of
the "bright spot" appearance of the luminaire itself, essentially
draws attention to the luminaire since it is the brightest of all
the objects illuminated, rather than having the brightest light
falling on the object of area desired to be illuminated. Ideally, a
luminaire which evidences an improved appearance both in daylight
and at night as well as one which rather than attracting attention
to the luminaire itself creates a pleasing atmosphere of bright
moonlight on the area or object to be illuminated would greatly
enhance the asthetic value of the luminaire to an overall landscape
or area.
SUMMARY OF THE INVENTION
This invention is directed to a luminaire which provides low angle,
glare-free, ground or road level lighting not unlike the pleasing
atmosphere of bright moonlight by providing in such luminaire a
base which includes means for mounting a lamp socket and lamp
therein, a cylindrical lens defining a lamp cavity positioned above
the base and arranged to surround the lamp and at least a portion
of the lamp socket, a plurality of annular louver members
surrounding the cylindrical lens and stacked one above the other,
spacer means separating each of the annular louver members from its
adjacent louver member; and a cover member overlying the lamp
cavity, the upper edge of the cylindrical lens and at least a
portion of the uppermost louver to thereby close off the top of the
luminaire. The cover member may further include a central lens
portion for the vertical release of light.
BRIEF DESCRIPTION OF THE DRAWING
The attendant advantages of this invention will become more readily
apparent and better understood as the following detailed
description of an exemplary embodiment of this invention is
considered in connection with the accompanying drawings, in
which:
FIG. 1 is a side elevational view illustrating the external
appearance of the luminaire of this invention;
FIG. 2 is a sectional view taken along the line II--II of FIG.
1;
FIG. 3 is a sectional view taken along the line III--III of FIG. 2;
and
FIG. 4 is a bottom view of the luminaire of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in detail to the drawings wherein like reference
characters represent like parts throughout the several views, there
is illustrated in FIG. 1 an area lighting luminaire constructed in
accordance with this invention and generally designated 10. The
luminaire 10 when viewed externally includes a base generally
designated 12 which may comprise an upper annular dish portion 14
and a lower annular dish portion 16. Situated above the base
portion 12 and surrounding the light source and lens are a
plurality of radially and downwardly extending louvers 18. Closing
off the top of the luminaire is a top or cover member 20 which may
or may not include a central annular disc-like lens 22 which will
permit light to be directed vertically from the luminaire.
Referring now to FIG. 2 there is illustrated a sectional view of
the luminaire of this invention. As illustrated the luminaire base
portion 12 is secured to an upright pole or post 24 when the
luminaire is to be mounted as a post top luminaire. Alternatively,
for walkway lighting and other applications where a wide spread or
light is not indicated the luminaire may be mounted on a pedestal
which may for example conform to the diameter of the luminaire base
portion 14. In the embodiment illustrated in FIGS. 1 and 2 the base
12 is shown in a two-part configuration which includes an upper
dished portion 14 and a lower deeper dished portion 16. The portion
of the base 16 can be eliminated when an incandescent lamp, not
requiring a ballast or large lamp socket, is employed as the source
of illumination. As illustrated, however, in the embodiment of
FIGS. 1 and 2 the lower base portion 16 includes a mounting plate
26 to which there are secured by for example, bolts 28 mounting
brackets 30 and 32 which serve to support a ballast coil 34 and
lamp socket 38, respectively.
A lamp 40 is mounted in the lamp socket 38 and is surrounded by an
integral louver and lens assembly which forms a unitary central
light distributing housing for the luminaire 10.
The integral louver and lens assembly includes a cylindrical
refractor or lens 42 which may preferably be of the fresnel type, a
plurality of identical louver rings 16, upper and lower louver
rings 44 and 46, respectively, tubular spacers 48 and threaded rods
50. The integral louver and lens assembly is assembled by placing
alternately on a plurality of rods 50, a plurality of louvers 16
with spacers 48 interposed between each of the louvers 16. The
louvers 16 have a flat ring portion 17 which includes a plurality
of apertures therein to receive the rods 50 therethrough. The
remainder of the louver 16 extends outwardly or radially and
downwardly from the flat ring portion 17. The spacers 48 are so
dimensioned that when interposed between a pair of louver members
16 on the rod 50, the outward, lowermost portion of an upper louver
lies in approximately the same horizontal plane as the flat ring
portion 17 of the next lower louver 16. This construction shields
direct light from the lamp 40 from a viewer's horizontal or higher
than horizontal line of sight with the luminaire. The upper and
lower louvers differ from the remaining louvers 16 in that they
each have a downwardly projecting flange 45 and 47, respectively,
to facilitate the attaching of the central light distributing
housing to the base 12 and the top cover 20. In addition, the upper
and lower end louvers 44 and 46 include an inwardly projecting
flange which is essentially an extension of the ring portion 17 of
the remaining louvers. These inwardly projecting flanges 45a and
47a serve to retain the refractor or lens 42 in the integral louver
and lens assembly by coacting with indentations 43 on the upper and
lower ends of the lens 42.
The louver and lens assembly forming the central light distributing
housing is secured to the base 12 by a plurality of screws 52 and
the top cover member 20 is secured to the upper louver 44 at its
flange 45 by similar screws 54.
The top cover member 20 may be completely closed as illustrated in
phantom through the lens 22 or when it is desired to light a tree
or sign or some similar object situated above the luminaire, the
lens 22 may be sealed into an annular opening 21 in the top of
cover member 20. Additional downlighting may also be provided by
providing apertures 56 in the bottom wall of the upper base portion
14, an annular ring in the form of, for example a plastic lens 58,
may be then positioned within the upper housing 14 to overlie the
apertures 56 to refract light exiting through the apertures 56.
The interior surface of the louvers 16 are preferably painted white
to reflect light transmitted through refractor or lens 42
downwardly with as little loss as possible. The angles of the
louvers 16 and their spacing along the rods 50, are such that no
illumination can be seen through the sides of the luminaire at
viewing angles at the horizontal or above and all light is
essentially directed downwardly upon the area to be illuminated. It
should be readily apparent that the area lighting luminaire of this
invention has many applications with respect to the asthetic
illumination of objects due to its ability to eliminate the bright
source which will normally attract the viewer's attention.
* * * * *