Information
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Patent Grant
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6402349
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Patent Number
6,402,349
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Date Filed
Monday, July 30, 200124 years ago
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Date Issued
Tuesday, June 11, 200223 years ago
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CPC
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US Classifications
Field of Search
US
- 362 330
- 362 331
- 362 222
- 362 223
- 362 147
- 362 148
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International Classifications
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Abstract
A dual-surface lens for light fixtures and T-bar ceilings includes a first lens panel having a planar perimeter around a decorative or optical control area and a second lens panel having a planar perimeter resting on the planar perimeter of the first lens panel. In a preferred embodiment the first lens panel depends below the planar perimeter and the second lens panel extends above the planar perimeter at an angle of from 5° to 15°.
Description
BACKGROUND OF THE INVENTION
This invention applies to the field of light fixture lenses and more particularly to the square or rectangular lens panels used as diffusers on fluorescent light fixtures. Such lenses are often installed into recessed or surface-mounted fluorescent light fixtures, or are made to rest on the flanges of the T-bar grid openings that are illuminated from above.
DESCRIPTION OF THE PRIOR ART
Some prior art light fixture lenses are simply white opal translucent plastic sheets or prismatic light control patterns. All such prior art lenses have three short-comings.
First, all fluorescent lamps emit significant UV (ultraviolet radiation) that is harmful to humans, as well as damaging to photosensitive materials, such as textiles, documents and other organic materials. Most prior-art fluorescent lenses do not have enough thickness to stop such radiation.
Second, all fluorescent lamps emit significant IR (infrared radiation) that is uncomfortable to humans, as well as damaging to heat sensitive materials, such as paintings, painted wood, animal specimens and other organic materials that are subject to being dried out. Most prior-art fluorescent lenses do not have enough thickness to stop such radiation.
Third, prior-art lenses tend to accumulate internal dirt and dead insects that are attracted to the light and remain trapped in the fixture until they die and fall onto the inner surface of the lenses, making the fixtures look dirty and unsightly.
PURPOSE OF THE PRESENT INVENTION
The first purpose of the present invention is to provide a lighting lens capable of blocking UV radiation. The second purpose of the invention is to provide a lighting lens capable of blocking IR radiation. The third purpose of the invention is to provide a lens in which trapped debris particles and dead insects are not visible.
BRIEF DESCRIPTION OF THE INVENTION
The foregoing purposes are achieved by a dual-surface lens for light fixtures and T-bar ceilings in which a first lens panel has a planar perimeter around a central area of decorative or optical control and a second lens panel has a planar perimeter resting on the planar perimeter of the first lens panel. In a preferred embodiment the central area of the first lens panel is flush with or depending below the planar perimeter and the second lens panel is pyramidal and extending above the planar perimeter at an angle of 5° to 15°.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a cross-sectional elevation view of a prior-art lens, shown in a typical fluorescent light fixture with a flat, prismatic lens;
FIG. 2
is a cross-sectional elevation view of a prior-art lens, shown in a typical T-bar suspended ceiling, with a sculpted, decorative lens;
FIG. 3
is a cross-sectional elevation view of a prior-art lens, shown in a typical fluorescent light fixture with a flat, prismatic lens;
FIG. 4
is a cross-sectional elevation view of a prior-art lens, shown in a typical T-bar suspended ceiling, with a sculpted, decorative lens;
FIG. 5
is an enlarged cross-sectional elevation view of detail
5
of
FIG. 4
, showing a preferred embodiment of the invention; and
FIG. 6
is an enlarged cross-sectional elevation view of a second preferred embodiment of the invention
REFERENCE NUMERALS IN THE DRAWINGS
|
1 prismatic lens
2 fluorescent fixture flange
|
3 fluorescent light fixture
4 insects
|
5 debris
6 fluorescent lamp
|
8 decorative embossed lens
9 T-bar flanges
|
10 T-bar
12 fluorescent lamp
|
15 dual-surface lens
16 first lens panel
|
17 first lens perimeter
18 light fixture flanges
|
19 optical control area
20 fluorescent lighting fixture
|
21 perimeter of second lens
22 raised pyramid area
|
23 pyramid peak
24 second lens panel
|
26 first lens panel
27 planar perimeter
|
29 T-bar flange
30 T-bars
|
32 bonding
35 fasteners
|
|
DETAILED DESCRIPTION OF THE DRAWINGS
In
FIG. 1
a prior art prismatic lens
1
is shown installed on flanges
2
of a fluorescent light fixture
3
. Insects
4
and debris particles
5
have found their way into the fixture are clearly visible on the lens, normally right under lamps
6
.
In
FIG. 2
a prior art decorative embossed lens
8
is shown installed on flanges
9
of suspended ceiling T-bars
10
under fluorescent lamps
12
. Insects
4
and debris particles
5
have found their way onto the lens, normally right under lamps
12
.
In
FIG. 3
a dual-surface lens
15
is shown having a first lens panel
16
having a planar perimeter
17
adapted to rest on a flanges
18
of a light fixture
20
, said planar perimeter enclosing an optical control area
19
. A second lens panel
24
has a planar perimeter
21
adapted to rest on the planar perimeter
17
of the first lens panel. Said second lens panel planar perimeter
21
encloses a raised pyramid area
22
with a central peak
23
and edges contiguous with the planar perimeter
21
. Pyramid area
22
may be comprised of any clear or translucent diffusing material common in the lighting industry. Insects
4
and debris particles
5
have found their way onto the lens, normally right under lamps
6
. However, the pyramid area, having angle “A” slope angles from 5° to 15° between the peak
23
and the perimeter
17
, causes insects
4
and debris particles
5
to migrate to the perimeter
17
. The migration is facilitated by the buzzing of dying insects and natural ballast and ceiling vibrations. The result is that the insects and debris end up out if sight.
In
FIG. 4
a dual-surface lens
25
is shown having a first lens panel
26
having a planar perimeter
27
adapted to rest on a flanges
29
of suspended ceiling T-bars
30
. The lenses are illuminated by ceiling-mounted fluorescent lamps
12
. Planar perimeter
27
encloses an optical control area
26
having depending decorative patterns
29
. A second lens panel
24
is identical to panel
24
of
FIG. 3
, having a planar perimeter
21
adapted to rest on the planar perimeter
27
of the first lens panel
26
. Second lens planar perimeter
21
encloses a raised pyramid area
22
with a central peak
23
and edges contiguous with the planar perimeter
27
of first lens
26
. The pyramid area
22
may be comprised of any clear or translucent diffusing material common in the lighting industry. Insects
4
and dirt particles
5
may find their way onto the lens, normally right under a lamp
12
. However, the pyramid area
22
, having angle “A” slope angles from 5° to 15° between the peak
22
and the perimeter
21
, causes insects
4
and dirt particles
5
to migrate to the perimeter
21
. The migration is facilitated by the buzzing of dying insects and natural ballast and ceiling vibrations. The result is that the insects and debris do not remain under the lamps, but end up out if sight on the perimeter
21
of the second lens
24
.
In
FIG. 5
a dual-surface lens
25
is shown having a first lens panel
26
attached to second lens panel
24
with bonding
32
selected from the group including solvent adhesive bonding, thermal bonding, double-sided adhesive tape. This forms a rigid hollow structure that prevents the lens from bending or warping in service.
In
FIG. 6
dual-surface lens
25
is shown having a first lens panel
26
attached to second lens panel
24
with fasteners
35
selected from the group including integral snap fasteners and hook-and-loop fasteners.
Lens material thicknesses of lenses
16
and
26
are usually insufficient to stop al UV and IR from lamps, but they are economical to form in complex patterns. However, the simple shape of the pyramidal second lens panel may be made of thicker material to better absorb UV and IR.
SUMMARY, RAMIFICATIONS AND SCOPE
The purposes of the present invention are achieved and in practice provides a practical and inexpensive method for a flat, rigid lens capable of filtering UV and IR out of the transmitted light and causing Insects and debris particles to migrate to the perimeter of a lighting and end up out if sight. I will be obvious to anyone skilled in the art to employ other shapes and angles that will perform the same functions within the scope and spirit of the present invention.
Claims
- 1. A dual-surface lens (15, 25) for light fixtures and T-bar ceilings including:a first lens panel (16, 26) having a planar perimeter (17, 27) adapted to rest on a light fixture flange (18) or T-bar ceiling flange (29), said planar perimeter enclosing a decorative or optical control area (16, 29); and a second lens panel (24 ) having a planar perimeter (21) adapted to rest on the planar perimeter (17, 27) of the first lens panel, said second lens panel planar perimeter enclosing a raised pyramid area (22) with a central peak (23) and edges contiguous with the planar perimeter (21), said pyramid area comprising clear or translucent diffusing material.
- 2. A dual-surface lens for light fixtures and T-bar ceilings according to claim 1 in which the second lens panel pyramid has sides (22) extending from the perimeter flange (21) to the peak (23) at an angle from 5° to 15°.
- 3. A dual-surface lens for light fixtures and T-bar ceilings according to claim 1 in which the first lens panel (16) optical or control area (19) is selected from the group including clear or translucent prismatic or irregular patterns.
- 4. A dual-surface lens for light fixtures and T-bar ceilings according to claim 1 in which the first (16, 26) and second (24) lens panels are joined together with fasteners (32, 35) selected from the group including solvent adhesive bonding, thermal bonding, double-sided adhesive tape, integral snap fasteners and hook-and-loop fasteners.
- 5. A dual-surface lens for light fixtures and T-bar ceilings according to claim 1 in which the second lens panel (24) pyramid area (22) is generally polygonal.
US Referenced Citations (4)
| Number |
Name |
Date |
Kind |
|
3117729 |
Silvers et al. |
Jan 1964 |
A |
|
5025349 |
Gow |
Jun 1991 |
A |
|
5791764 |
Jaksich |
Aug 1998 |
A |
|
5863114 |
Nagatani et al. |
Jan 1999 |
A |