U.S. patent number RE36,908 [Application Number 09/111,867] was granted by the patent office on 2000-10-10 for ceiling mounted wallwash light fixture.
This patent grant is currently assigned to Cooper Industries, Inc.. Invention is credited to Geoffrey Ling.
United States Patent |
RE36,908 |
Ling |
October 10, 2000 |
Ceiling mounted wallwash light fixture
Abstract
A ceiling mounted, recessed, wallwash light fixture includes a
reflector having an internal reflecting surface. A wallwash segment
of that reflecting surface is defined by vertically adjacent
reflecting faces each arranged so that an effective lowest point of
brightness seen by the reflecting face is reflected along a line
passing below an opposing portion of a bottom edge of the
reflector. The wallwash segment can be defined by an insert
attached to the reflecting surface.
Inventors: |
Ling; Geoffrey (North
Barrington, IL) |
Assignee: |
Cooper Industries, Inc.
(Houston, TX)
|
Family
ID: |
23538124 |
Appl.
No.: |
09/111,867 |
Filed: |
July 8, 1998 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
389403 |
Feb 16, 1995 |
05535110 |
Jul 9, 1996 |
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Current U.S.
Class: |
362/297; 362/148;
362/346; 362/348; 362/350 |
Current CPC
Class: |
F21S
8/02 (20130101); F21S 8/04 (20130101); F21V
7/0025 (20130101); F21V 7/09 (20130101); F21V
7/10 (20130101); F21Y 2103/37 (20160801) |
Current International
Class: |
F21V
7/00 (20060101); F21V 7/09 (20060101); F21V
7/10 (20060101); F21S 8/04 (20060101); F21V
007/00 () |
Field of
Search: |
;362/297,147,148,346,347,348,349,304,350 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tso; Laura K.
Attorney, Agent or Firm: Fish & Richardson P.C.
Claims
What is claimed is:
1. A recessed, ceiling-mount wallwash light fixture for use with a
lamp, comprising a reflector body including an internal reflector
surface forming a cavity; said reflector body having a lower edge
defining a bottom opening of said cavity; said reflector surface
including a wallwash segment extending around less than the entire
inside perimeter of said reflector surface, said wallwash segment
forming a plurality of vertically adjacent reflecting faces
oriented at respective inclinations with respect to vertical for
reflecting light below an opposite portion of said edge, said
wallwash segment being vertically stepped in that each reflecting
face is separated from a vertically adjacent reflecting face by a
circumferentially extending non-reflecting step-defining face which
interconnects a top edge of a reflecting face with a bottom edge of
another reflecting face disposed thereabove.
2. The fixture according to claim 1, wherein said reflecting faces
located adjacent a lower edge of said reflector have smaller
heights than said reflecting faces located adjacent a upper end of
said reflector.
3. The fixture according to claim 1, wherein said cavity has a
circular cross-section.
4. The fixture according to claim 3, wherein each reflecting face
is circumferentially continuous from one edge of said segment to a
circumferentially spaced opposite edge thereof.
5. The fixture according to claim 1, wherein said reflecting faces
are straight as viewed in a cross-sectional plane containing said
axis.
6. The fixture according to claim 1, wherein said reflecting faces
are formed on an insert attached to said body.
7. The fixture according to claim 6, wherein said insert is
situated inside of said body.
8. The fixture according to claim 7, wherein said insert includes
an outer surface engaged flush against an inside surface of said
reflector body.
9. The fixture according to claim 6, wherein said insert comprises
a stiff plate.
10. The fixture according to claim 6, wherein said insert comprises
a film.
11. The fixture according to claim 1, wherein said reflecting faces
are formed on an insert engaged flush against an inside surface of
said body, said insert comprising a stiff plate attached to said
body by adhesive.
12. The fixture according to claim 6, wherein a lower edge of said
insert substantially coincides with said lower edge of said
body.
13. The fixture according to claim 6, wherein a lower edge of said
insert extends downwardly past said lower edge of said body.
14. The fixture according to claim 1, wherein said reflecting faces
are of one-piece integral construction with said body.
15. The fixture according to claim 8, wherein said insert extends
circumferentially for about one hundred twenty degrees.
16. The fixture according to claim 1 wherein said reflecting faces
are generally vertical, and said step defining faces are generally
horizontal.
17. A wallwash insert mountable in a reflector body of a recessed,
ceiling-mount wallwash light fixture for reflecting light toward an
adjacent vertical wall, said insert being curved and including
outer and inner surfaces, said inner surface forming a plurality of
vertically adjacent reflecting faces oriented at different angles
with respect to vertical, said upper edge being of smaller radius
than said lower edge, said wallwash insert being vertically stepped
in that each reflecting face is separated from a vertically
adjacent reflecting face by a circumferentially extending
non-reflecting step-defining face which interconnects a top edge of
a reflecting face with a bottom edge of another reflecting face
disposed thereabove.
18. The insert according to claim 17, wherein said reflecting faces
located adjacent said lower edge of said insert have smaller
heights than said reflect faces located adjacent said upper edge of
said insert.
19. The insert according to claim 17, wherein said insert extends
for an angle of about one hundred twenty degrees.
20. The fixture according to claim 17 wherein said reflecting faces
are generally vertical, and said step defining faces are generally
horizontal. .Iadd.
21. A recessed, ceiling-mount wallwash light fixture for use with a
lamp, comprising a reflector body including an internal reflector
surface; said reflector body having a lower edge; said reflector
surface including a wallwash segment extending around less than the
entire inside perimeter of said reflector surface from one upright
side edge of said wallwash segment to another upright side edge
thereof, said wallwash segment forming a plurality of vertically
adjacent reflecting faces oriented at respective inclinations with
respect to vertical for reflecting light below an opposite portion
of said edge, said wallwash segment being vertically stepped in
that each reflecting face is separated from a vertically adjacent
reflecting face by a non-reflecting step-defining face which
extends from said one upright side edge to said other upright side
edge and interconnects a top edge of a reflecting face with a
bottom edge of another reflecting face disposed
thereabove..Iaddend..Iadd.22. A wallwash insert mountable in a
reflector body of a recessed, ceiling-mount wallwash light fixture
for reflecting light toward an adjacent vertical wall, said insert
including a top edge and a bottom edge interconnected by upright
side edges, said insert being curved from said top edge to said
bottom edge and including outer and inner surfaces, said inner
surface forming a plurality of vertically adjacent reflecting faces
oriented at different angles with respect to vertical, said
wallwash insert being vertically stepped in that each reflecting
face is separated from a vertically adjacent reflecting face by a
non-reflecting step-defining face which interconnects a top edge of
a reflecting face with a bottom edge of another reflecting face
disposed thereabove, each of said step-defining faces extending
from one of said upright side edges of said insert to another of
said opposite upright side edges..Iaddend.
Description
BACKGROUND OF THE INVENTION
The present invention relates to recessed, ceiling-mounted wallwash
light fixtures.
It is conventional to illuminate a vertical wall of a room by
recess-mounting a wallwash light fixture in the ceiling at a
predetermined distance from the wall. The fixture includes a
reflector having an internal reflecting surface, a segment of which
being oriented to reflect light toward the wall. That segment can
comprise an external secondary reflector element mounted on the
outside of the main reflector after a window has been cut therein
(e.g., see U.S. Pat. No. 4,742,440). Alternatively, the secondary
reflector element can be mounted on the inside of the main
reflector (e.g., see U.S. Pat. No. 4,475,147). A shortcoming of
conventional wallwash fixtures is that light is reflected off the
secondary reflector element in a somewhat imprecise manner, whereby
the wall is not uniformly illuminated, and/or stray light reflected
from the secondary reflector element contacts an opposite side of
the fixture interior. For example, as depicted in FIG. 12, a main
reflector 5 has a hole cut therein, and a wallwash attachment 3 is
applied across the outside of the hole light from a point of
brightness on a lamp 1 reflects off a reflection point 2 of a
secondary wallwash reflector 3 and then off an opposite side 4 of
the main reflector 5 from which it is seen from below by a viewer
6. Such stray light causes unsightly brightness to the viewer
6.
It would, therefore, be desirable to provide a wallwash light
fixture of the recessed, ceiling-mount type having a secondary
reflector segment which reflects light in a highly precise manner
toward the wall to be illuminated.
SUMMARY OF THE INVENTION
The present invention relates to a recessed, ceiling-mount wallwash
light fixture for use with a lamp, comprising a reflector body
which includes an internal reflector surface forming a cavity. The
reflector body has a lower edge defining a bottom opening of the
cavity. The reflector surface includes a wallwash segment extending
around less than the entire inside perimeter of the reflector
surface. The wallwash segment is vertically stepped to form a
plurality of vertically adjacent reflecting faces which are
oriented at respective inclinations with respect to horizontal for
reflecting light below an opposite portion of the edge.
The reflecting faces are preferably formed on an insert which is
attached to the reflector body. The insert may comprise a stiff
plate, or a film.
The present invention also relates to the configuration of the
insert per se.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of the invention will become apparent
from the following detailed description of preferred embodiments
thereof in
connection with the accompanying drawings in which like numerals
designate like elements and in which:
FIG. 1 is a vertical sectional view taken through a reflector which
is recess-mounted in a ceiling, and which possesses a wallwash
reflecting structure according to the present invention;
FIG. 2 is a top plan view of a wallwash insert shown in FIG. 1;
FIG. 3 is a side elevational view of the insert depicted in FIG.
2;
FIG. 4 is a sectional view taken along the line 4--4 in FIG. 2;
FIG. 5 is an enlargement of a portion of the insert depicted in
FIG. 4;
FIG. 6 is a fragmentary perspective view depicting the manner of
mounting a wallwash reflector insert in the reflector;
FIG. 7 is a view similar to FIG. 5 of an alternative embodiment of
the present invention;
FIG. 8 is a view similar to FIG. 7 of yet another alternative
embodiment of the invention;
FIG. 9 is a perspective view of an alternative insert according to
the invention having a pattern of rectangular facets;
FIG. 10 is a view similar to FIG. 1 of an alternative form of
reflector in which the present invention is disposed;
FIG. 11 is a view similar to FIG. 1 of another form of reflector in
which the present invention is disposed; and
FIG. 12 is a vertical sectional view of a prior art wallwash
reflector.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
A recessed, ceiling mounts wallwash light fixture 10 depicted in
the drawings includes a reflector body 12 adapted to be
recess-mounted in a ceiling C. The manner of mounting the reflector
in a conventional recessed fixture housing 19 is well known to
those skilled in the art and need not be described in detail. The
reflector body includes an internal specular surface 14 which
defines a downwardly open cavity 16. A circular lower edge 18 of
the reflector forms the open bottom of the cavity and defines a
vertical longitudinal axis L of the cavity. The cross-sectional
area of the cavity becomes progressively smaller in an upward
direction.
Situated at an upper end of the cavity is a lamp 20 of any suitable
type, the lamp being recessed with respect to the open bottom of
the cavity. The lamp 20 can be mounted to a portion of the fixture
housing 19.
The internal specular surface 14 of the cavity includes a first
segment 14A which is continuously smooth, and a second segment 14B
which defines a wallwash reflector segment. That wallwash reflector
segment has a vertically stepped profile, defining a plurality of
vertically adjacent reflecting faces designed in accordance with
its position in relation to the lamp and the bottom opening of the
reflector body, as will be explained below. The reflector is in the
form of a downlight/wallwasher, meaning that the first segment 14A
is designed to reflect a significant portion of direct light from
the lamp downwardly to illuminate the area located beneath the
fixture.
In a first embodiment of the invention (see FIGS. 2-5), the
wallwash segment 14B is formed as part of an insert 22 which is
mounted to the body 12 within the cavity 16. The insert 22 extends
about one-third of the perimeter of the surface 14, i.e., above
one-third of the circumference of the surface in the case of a
cavity having a circular cross section. Preferably, the insert
extends for an angle A of about 120 degrees .Iadd.from one upright
side edge of the reflector segment to the opposite upright side
edge thereof.Iaddend.. A lower edge 21 of the insert has a greater
radius than an upper edge 23 thereof as is evident from FIG. 2. As
shown most clearly in FIGS. 4 and 5, the insert 22 comprises a
curved plate having a smooth outer surface 24, and a stepped inner
surface 26.
The outer surface 24 is configured with the same curvature as the
body 12 so that the insert 22 lies flush thereagainst. Most
preferably, the insert 22 is attached by an adhesive. However, any
suitable type of mechanical connection could be used. For example,
as shown in FIG. 6, a plurality of bosses 28 project from the outer
surface 24 and are adapted to pass through respective holes 25
formed in the body 12 and then become secured by conventional clips
27 to the body 12. The clips slide onto the bosses 28 so that
flexible teeth 29 of the clips grip the bosses. Other ways of
mounting the insert will be apparent to those skilled in the art.
For example, the bosses could form a snap-in connector with the
holes, or could comprise bendable tabs.
The inner surface 26 of the insert 22 includes steps 30 disposed
one above the other, i.e., in vertically or longitudinally adjacent
relationship (with reference to the longitudinal axis L). Each step
extends circumferentially with reference to the axis L and includes
a generally horizontal step-defining face 34 interconnecting a top
edge of one reflecting face with a bottom edge of the generally
upright or vertical reflecting face 32 disposed thereabove. The
faces 34 need not be horizontal, but could be inclined relative to
horizontal.
The reflecting faces 32 are oriented at respective inclinations
with respect to a vertical plane for reflecting light below an
opposite portion of the edge 18. Preferably, the inclination of
each reflecting face is such that the effective lowest point of
brightness "seen" by that face is reflected along a line passing
below a portion of the edge 18 disposed opposite face. A point of
brightness can be defined in different ways, but every reflecting
face should be designed in accordance with the selected
definition.
For example, the points of brightness could be defined firstly as
being only points on the lamp 20 itself. That is, with attention
directed to FIG. 1, if two points C and D on the lamp are
considered with reference to a reflecting face 32 having a
reflecting point 32A, it can be seen that reference or incidence
lines 37 and 39 can be drawn from the points C, D, respectively, to
the reflecting point 32A. The line 37 forms an angle C' with a
vertical plane, whereas the line 39 forms a smaller angle D' with
vertical. The effective lowest point of brightness would be defined
in this case as the point whose line of incidence forms the largest
angle relative to vertical, namely point C. By orienting the
reflecting face on which point 32A is disposed so that the light
represented by line 37 is reflected off point 32A in a direction
37' passing below the opposite portion of the edge 18, it is
ensured that light from all points of brightness disposed above
point C and reflecting off point 32A (and its associated reflecting
face) will also pass below the edge 18, rather than reflecting off
the downlight surface segment 14A located above the edge 18.
Consequently, the brightness of the surface segment 14A when viewed
from below will be minimized.
Alternatively, it might be desired to define a point of brightness
in a second manner to include not only points on the lamp, but also
points on the reflector which appear bright or "flashed" in that
they have similar luminance to the lamp itself. For example, with
reference to FIG. 11, light traveling from the lamp 20 to a point B
on the specular reflector along line 47 is reflected to the
reflecting point 32A along line 47' which forms an angle B' with
vertical. All other lines from point 32A to the reflector forming a
larger angle with vertical will not pass through the lamp, e.g.,
see broken line 45, 45' which reflects off point E. Hence, the
light on point B is "flashed" with respect to point 32A, whereas
light on point E is not "flashed" with respect to point 32A. Note
also, that light traveling to point 32A directly from point F on
the lamp 20 along line 49 forms a smaller angle with vertical than
the line 47'.
Accordingly, under the second definition of effective lowest point
of brightness, the point B would constitute the effective lowest
point of brightness with respect to the reflecting surface on which
point 32A is disposed. Therefore, by orienting that reflecting
surface so that light from point B is reflected below the opposite
portion of edge 18 (i.e., so that the line 47" passes below the
edge 18), it is ensured that light from all points of brightness
(as defined under the second definition) disposed above the point B
will also pass below that edge, rather than reflecting off the down
light surface segment 14A located above the edge 18. As a result,
the brightness of the surface segment 14A when viewed from below
will be minimized as pointed out earlier.
The effective lowest point of brightness in connection with a type
of reflector 40 having a diffuse type of reflecting surface 42,
such as depicted in FIG. 10, could be defined by the lowest point
44 on that diffuse reflecting surface 42. Lines of incidence from
that lowest point 44 to each reflecting face are shown in FIG. 10,
and it will be appreciated that all of those lines extend below the
edge 18.
As regards the reflecting surfaces 32 themselves, the uniformity of
light reflected thereby can be maximized by minimizing the height
of the reflecting face, especially as regards the lowest reflecting
faces. Thus, at least the lowest reflecting faces, e.g., lowest ten
reflecting faces, have identical, short heights H (e.g., 2 mm). The
remaining reflecting faces could also have the same height H, but
in order to reduce the cost of manufacture, they preferably have
progressively increasing heights which increase gradually, e.g., by
five percent per step.
The insert 22 can be formed of any suitable material, such as a
machined or molded metal which may be polished or metallized, or
metallized plastic, for example, vacuum metallized injection-molded
polycarbonate with a UV resistant and scratch resistant lacquer.
The reflector body 12 is preferably formed of aluminum.
The reflecting faces 32 can be of any suitable shape when viewed in
cross-section. For example, as shown in the cross-sectional view of
FIG. 5, the reflecting faces 32 can be straight. Alternatively,
they could comprise other shapes, such as a section of an ellipse,
or a section of a macrofocal ellipse for example.
Instead of comprising a stiff plate, the insert 22 could be formed
of a film to which miniaturized steps have been applied. The film
could be secured to the body 12 by adhesive.
Instead of being formed as part of a film or an insert 22, the
reflecting faces 32 could be of integral one piece construction
with the body 12 as shown in FIG. 7, such as by being integrally
molded or cast therewith, or being machined into the body 12.
It may be desirable to form the reflecting faces as an arrangement
of facets 50 as depicted on the reflector 48 shown in FIG. 8. The
facets could be of any suitable shape and are designed to reflect
the light in the same manner as the aforementioned faces 32 of
steps 30. For example, each facet could form a flat or curved
reflecting face. An insert 55 having a rectangular facet pattern is
depicted in FIG. 9.
In order to enable the very top portion of the wall to be
illuminated, the insert could be configured so that a lower portion
60 thereof (see the phantom lines in FIG. 5) extends slightly below
the edge 18.
It will be appreciated from the foregoing, that the present
invention provides an insert for converting a reflector of standard
shape into a wallwash reflector without resulting in an increase in
space occupied by the reflector. The insert is easy to install and
avoids excessive brightness of the reflector when viewed from
below. Also, the reflector minimizes the generation of "fringes" on
the wall being illuminated.
While the present invention has been disclosed in connection with
an insert which affixes in a flush manner to the inside reflector
surface, it is applicable to inserts attached in any manner to the
reflector body, as well as to the type of insert which is attached
to the outside of a reflector body across a window cut therein as
depicted in FIG. 11.
The embodiments disclosed herein are of the single wallwash type.
However, the invention is applicable to (a) double wallwashers
wherein inserts 22 would be mounted on opposite sides of the
reflector, and (b) corner wallwashers wherein two inserts 22 would
be arranged side-by-side to subtend a total angle of
240.degree..
The reflector bodies described herein are of the type wherein the
cavity has a circular cross section alternatively, the reflector
body could form a cavity having a rectangular cavity (as viewed
from below).
Although the present invention has been described in connection
with preferred embodiments thereof, it will be appreciated by those
skilled in the art that additions, deletions, modification, and
substitutions not specifically described may be made without
departing from the spirit and scope of the invention as defined in
the appended claims.
* * * * *