U.S. patent number 3,860,903 [Application Number 05/454,984] was granted by the patent office on 1975-01-14 for high output low brightness ventilated luminaire.
This patent grant is currently assigned to Westinghouse Electric Corporation. Invention is credited to Frank Van Steenhoven.
United States Patent |
3,860,903 |
Van Steenhoven |
January 14, 1975 |
HIGH OUTPUT LOW BRIGHTNESS VENTILATED LUMINAIRE
Abstract
A multi-purpose, high output, low brightness luminaire employing
a large open front box-like housing with opposed lamp sockets in
the side walls adapted to accommodate high wattage, high intensity
discharge (HID) lamps is disclosed. Upper and lower curved
reflectors are mounted adjacent the back wall of the housing and an
oppositely curved intermediate, perforated reflector overlies a
space between the upper and lower reflectors. The perforated
reflector directs air entering through the back wall both through
the perforations to sweep the lamps as well as upwardly and
downwardly over the upper and lower curved reflectors. A perforated
reflector screen is also provided across the luminaire in front of
the lamps to shield the lamp arcs from view and if desired, a
plurality of vertically and horizontally oriented louvers are
provided to selectively control light distribution.
Inventors: |
Van Steenhoven; Frank (Hudson,
OH) |
Assignee: |
Westinghouse Electric
Corporation (Pittsburgh, PA)
|
Family
ID: |
23806888 |
Appl.
No.: |
05/454,984 |
Filed: |
March 26, 1974 |
Current U.S.
Class: |
362/279; 362/232;
362/294 |
Current CPC
Class: |
F21V
11/04 (20130101); F21V 7/0033 (20130101); F21V
11/14 (20130101); F21V 7/0025 (20130101); H01J
61/52 (20130101); F21V 13/10 (20130101); F21V
29/60 (20150115); F21W 2131/40 (20130101); F21W
2131/407 (20130101); F21W 2131/406 (20130101); F21W
2131/105 (20130101); F21V 21/30 (20130101) |
Current International
Class: |
F21V
29/00 (20060101); F21V 29/02 (20060101); F21V
11/00 (20060101); F21V 11/14 (20060101); F21v
029/00 () |
Field of
Search: |
;240/47,41R,41.1,41.15,41.35R,41.35A,41.35P,46.07,46.31,46.33,46.37,3,13R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Moses; Richard L.
Attorney, Agent or Firm: Studebaker; B. R.
Claims
What is claimed is:
1. A high output, low brightness luminaire comprising:
a housing, including a back wall, side walls a top wall and a
bottom wall;
a pair of opposed discharge lamp sockets mounted in said side walls
approximately midway between said top wall and said bottom
wall,
a pair of concave reflectors, one of said reflectors mounted
adjacent the top half of said back wall and the other of said
reflectors mounted adjacent the bottom half of said back wall,
a convex reflector mounted between said concave reflectors and
overlying the bottom edge of the upper reflector and the top edge
of the lower reflector, and;
a perforated shield extending across said housing from one side
wall to the other side wall approximately midway between said top
wall and said bottom wall forward of said opposed discharge lamp
sockets, said perforated shield being constructed and arranged to
shield the arc of discharge lamps mounted in said opposed sockets
from view at normal viewing angles.
2. The high output, low brightness luminaire according to claim 1
wherein said perforated shield is curved and the side thereof
facing said lamp sockets is reflective.
3. The high output low brightness luminaire according to claim 2
wherein said perforated shield is less than 25 percent open.
4. The high output low brightness luminaire according to claim 1
wherein at least one air inlet is provided in said back wall
adjacent the center thereof and said convex relfector is
perforated.
5. The high output low brightness luminaire of claim 1 wherein a
plurality of light directing baffles are mounted in a vertical
array between said top wall and said bottom wall adjacent said
perforated screen, said light directing baffles being individually
and selectively adjustable to control the light output pattern of
said luminaire.
6. The high output, low brightness luminaire according to claim 1
wherein a plurality of light directing baffles are mounted in
horizontal array between said side walls forward of said perforated
screen, said light directing baffles being individually and
selectively adjustable to control the light output pattern of said
luminaire.
7. The high output low brightness luminaire according to claim 1
wherein two sets of light directing baffles are mounted in said
luminaire, a first set mounted between the top and bottom walls and
a second set mounted between said side walls with each baffle of
each set being individually and selectively adjustable to control
the light distribution of said luminaire.
8. A high output, low brightness, ventilated luminaire
comprising:
an open front housing including a back wall, side walls, a top wall
and a bottom wall;
a discharge lamp socket mounted approximately midway between said
top wall and said bottom wall in each of said side walls, said
discharge lamp sockets being arranged in facing relationship one to
the other;
an upper curved reflector mounted adjacent to the upper half of
said back wall;
a lower curved reflector mounted adjacent the lower half of said
back wall with the upper edge of said lower reflector being
slightly spaced from the bottom edge of said upper reflector;
an oppositely curved reflector overlying the lower edge of said
upper curved reflector, the upper edge of said lower curved
reflector and the space therebetween, said oppositely curved
reflector being perforated; and
at least one air inlet in said back wall proximate said space
between said upper and lower curved reflectors, whereby air passing
through said inlet in part passes through the perforations in said
oppositely curved reflector to sweep discharge lamps mounted in
said discharge lamps sockets and in part is redirected by said
oppositely curved reflector to sweep said upper and lower
reflectors.
9. The high output, low brightness, ventilated luminaire according
to claim 8 wherein a perforated shield is mounted across said
housing from one side wall to the other side wall approximately
midway between said top wall and said bottom wall forward of said
discharge lamp sockets, said perforated shield being constructed
and arranged to shield the arc of the discharge lamps mounted in
said sockets from view at normal viewing angles.
10. The high output, low brightness, ventilated luminaire according
to claim 9 wherein said perforated shield is curved and the side
thereof facing said lamp socket is reflective.
11. The high output, low brightness, ventilated luminaire according
to claim 10 wherein said perforated shield is less than 25 percent
open.
12. The high output, low brightness, ventilated luminaire according
to claim 9 wherein a plurality of light directing louvers are
mounted in vertical array between saidd top wall and said bottom
wall adjacent said perforated shield, said light directing louvers
being individually and selectively adjustable to control the light
output pattern of said luminaire.
13. The high output, low brightness, ventilated luminaire according
to claim 9 wherein a plurality of light directing louvers are
mounted in horizontal array between said side walls forward of said
perforated shield, said light directing louvers being individually
and selectively adjustable to control the light output pattern of
said luminaire.
14. The high output, low brightness, ventilated luminaire according
to claim 8 wherein two sets of light directing louvers are mounted
in said luminaire, a first set mounted between the top and bottom
walls and a second set mounted between said side walls with each
louver of each set being individually and selectively adjustable to
control the light distribution of said luminaire.
Description
BACKGROUND OF THE INVENTION
The application for a high output low brightness luminaire are many
and varied and the number of such applications continues to rise.
Unfortunately, these applications vary in their requirements to the
extent several different kinds of luminaires are presently required
to fulfill these many needs. Good color television of indoor
athletic events require high output, color corrected, lighting
generally with color corrected high intensity discharge lamps but
visual brightness must be reduced for the comfort of the spectators
present at the event. A multitude of industrial applications for
high output low brightness luminaires also exist and many of these
occur in somewhat dirty environments. Luminaire problems in dirty
environment industrial applications are well known and the buildup
of dirt and grime on open reflective surfaces and lamps has
essentially precluded the use of open luminaires in these
environments. Luminaires with sealed optical systems also have
their drawbacks in terms of relamping the fixture as well as
reduced light output from dirty refractors. Additionally, almost
all of these fixtures provide significant brightness problems for
people working in the environment when the luminaire is viewed
directly. The need is clear for a high output luminaire which
displays low brightness at normal viewing angles and has the
facility to maintain clean optical surfaces even in dirty
environments and in which the light distribution can be controlled
based upon the particular illumination required.
SUMMARY OF THE INVENTION
The versatile high output, low brightness, ventilated luminaire of
this invention fulfills many of the varied requirements of the
lighting industry particularly in the areas of arena and industrial
lighting situations. The high output, low brightness, ventilated
luminaire of this invention includes an open front housing with a
back wall, side walls, a top wall and a bottom wall with a
discharge lamp socket mounted approximately midway between the top
wall and the bottom wall in each of the side walls which discharge
lamp sockets are arranged in facing relationship with respect to
each other. Upper and lower curved reflectors are mounted adjacent
the upper half and lower half of the back wall respectively with
the upper edge of the lower reflector being slightly spaced from
the bottom edge of the upper reflector. An oppositely curved
perforated reflector ovelies the lower edge of the upper reflector
and the upper edge of the lower reflector and the space
therebetween with the oppositely curved perforated reflector
directing filtered air entering through an inlet in the back wall
through the perforations to sweep the discharge lamps mounted in
the sockets as well as upwardly and downwardly over the curved
reflectors to sweep them clean and prevent dirt buildup on the
reflector surfaces. A perforated shield is also mounted across the
housing from one side wall to the other, approximately midway
between the top wall and the bottom wall, forward of the discharge
lamp sockets to shield the arc of the discharge lamp from view at
normal viewing angles. Horizontally and vertically disposed baffles
or louvers may be mounted in the front part of the luminaire
housing, forward of the lamp sockets, which are individually and
selectively adjustable to control the particular light distribution
of the luminaire.
BRIEF DESCRIPTION OF THE DRAWING
Many of the attendant advantages of this luminaire will become more
readily apparent and better understood as the following detailed
description is considered in connection with the accompanying
drawing in which:
FIG. 1 is an isometric view of the luminaire of this invention with
portions of the housing broken away;
FIG. 2 is a front elevation view thereof; and
FIG. 3 is a sectional view taken along the line III--III of FIG.
2.
DESCRIPTION OF THE PREFERREDD EMBODIMENT
Referring now in detail to the drawing, wherein like reference
characters represent like parts throughout the several views, there
is illustrated the versatile high output, low brightness,
ventilated luminaire generally designated 10. The luminaire has a
box-like, open front, housing including a back wall 12, side walls
14 and 16, a top wall 18 and a bottom wall 20. A lamp socket 22 is
mounted on the interior surface of each of the side walls 14 and 16
approximately midway between the top wall 18 and the bottom wall
20. The sockets 22 are in an opposed relationship with respect to
each other and are adapted to receive any of several types of high
intensity discharge (HID) lamps such as, for example, the color
corrected metal halide lamp or the high pressure sodium ceramic
discharge lamp. A pair of such lamps are illustrated in the drawing
at 24. Upper and lower curved reflectors 26 and 28 are mounted
adjacent the back wall of the luminaire housing and are illustrated
in FIG. 3 as being retained by an air inlet mounting bracket 30.
Preferably three such air inlet brackets 30 are equidistantly
spaced across the back wall 12. It should be understood that the
upper and lower curved reflectors 26 and 28 may be mounted directly
to the back wall in any conventional manner in nonventilated
configurations of the luminaire of this invention. The upper of the
lower reflector 28 and the bottom edge of the upper reflector 26
are spaced slightly from each other and an oppositely curved
reflector 32 overlies that space as well as the bottom edge of the
upper curved reflector and the upper edge of the bottom curved
reflector 28. The oppositely curved reflector 32 is preferably
perforated and serves both as an air screen and a reflector in a
manner which will be later described.
A perforated shield or light screen 34 is mounted across the
housing from the side wall 14 to the side wall 16 approximately
midway between the top wall 18 and the bottom wall 20 slightly
forward of the discharge lamp sockets. The perforated shield or
screen 34 is curved and both transmits and reflects light emanating
from the discharge lamps while shielding the arc of the discharge
lamps from view at normal viewing angles.
If desired, particular light distribution patterns can be
selectively controlled through a plurality of horizontally and
vertically mounted louvers or baffles adjacent the front end of the
luminaire housing. A plurality of vertical posts 36 have mounted
thereon for rotation thereabout vertically disposed louvers or
baffles 38. Each of the louvers or baffles 38 are independently
rotatable through 180.degree. about the rods 36. Forward of the
baffles 38 are a plurality of horizontally disposed rods 40 which
extend from the side wall 14 to the side wall 16 and upon which are
mounted horizontal louvers or baffles 42. Each of the horizontal
baffles or louvers 42 is mounted for rotation about the horizontal
rods 40 through 180.degree. independently of each other and are
selectively positionable along with the vertical baffles or louvers
38 to selectively distribute the light from the luminaire 10 in a
selected light distribution pattern.
The luminaire 10 is primarily designed to accommodate a pair of
opppositely disposed 1000 watt gas discharge lamps 24 but it will
be readily apparent that the luminaire can accommodate lamps of
higher or lower wattage. The perforated diffusing light screen 34
is less than 25 percent and perferably about 18 percent open
perforated steel with a thin coating of baked enamel on the surface
facing the discharge lamps in order to reflect light which does not
pass through the screen back to the other reflective surfaces of
the luminaire housing as illustrated by the arrow in FIG. 3.
The entire interior surface of the luminaire housing is preferably
covered by a thin coat of baked white enamel including the
concavely curved upper and lower reflectors 26 and 28. The
oppositely, convexly curved perforated air screen 32 is also
preferably coated with a thin coat of baked white enamel and the
staggered perforations preferably render the screen less than 25
percent and about 18 percent open. The air screen 32 serves two
ventilating functions. In the preferred embodiment three 1-inch
diameter air inlet brackets 30 are equidistantly spaced across the
back wall and are adapted to direct filtered air at the air screen
32 with a portion of the air stream flowing through the
perforations which sweeps over the discharged lamps preventing dirt
from settling and building up on the lamps. The air screen 32 also
redirects a portion of the air stream upwardly and downwardly to
sweep the curved reflectors 26 and 28 to blow away dirt from the
reflective surfaces before it can settle thereon and reduce the
reflectivity of those areas. A third function of the oppositely
curved reflector, air screen 32 is to reflect light from the
discharge lamps out of the luminaire housing by way of other
reflective surfaces so that the light will not be reflected back
through the arcs.
The luminaire is illustrated as being mounted rotatably on a
gimbaled mounting bracket 44 at pivot points 46 which permits the
mounting bracket to be mounted through cross braces 48 either
vertically or horizontally with a wide range of variations in
aiming directions being thus available.
As will be apparent from the foregoing, the multipurpose, high
output, low brightness luminaire of this invention is highly
versatile in its applications as a high light output luminaire. The
curved perforated light diffusing screen 344 eliminates glare from
the arcs of the discharge lamps at normal viewing angles while
permitting light to pass directly from the luminaire housing while
reflecting the remainder of the direct light output to various
reflective surfaces of the interior of the luminaire housing to
provide for maximum illumination with minimum glare. The rear
reflective structure including the convexly curved perforated
intermediate reflector or air screen 32 permits air entering
through one or more inlets in the back wall of the housing to flow
both directly over the lamps to keep their surfaces clean as well
as redirecting the air in a manner which causes it to sweep the
primary reflective elements, curved reflectors 26 and 28, also
eliminating any buildup of dirt on these surfaces. The plurality of
vertically and horizontally disposed baffles or louvers 38 and 42
permit the luminaire light output to be selectively controlled in
order to provide an optimum light distribution pattern and better
fulfill the intended purpose of the luminaire.
* * * * *