Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION
OUTWARDLY PROJECTING AIR PURIFIER
FIELD OF THE INVENTION
[0001] The present invention relates to air purifiers. More specifically,
the present invention is concerned with a an outwardly projecting air purifier
comprising an assembly of UV lamps and reflector, allowing the air purifier to
be
used in air ducts and in other types of ventilation systems.
BACKGROUND OF THE INVENTION
[0002] Indoor Air Quality related problems, often referred to as "SICK
BUILDING SYNDROMES", costs the North American economy well over 100
billion dollars each year in health care, absenteeism, lost production time
and lost
revenue. This problem is compounded by the "Anthrax scare", since anthrax
spores (structures whose role is propagation) can be readily transported
through
the ventilation system of a building.
[0003] The human immune system often responds violently when
exposed to toxins released by bacteria and molds in ventilation systems, and
displays systems commonly called allergies. The microorganisms found in
buildings are viruses, bacteria and their components such as endotoxins, and
fungi
and their metabolic products such as mycotoxins and antigens.
[0004] Most environments contain a large variety of bacteria. Health
risks increase only when the pathogen bacteria concentration is permitted to
amplify in an indoor environment, and these organisms or their by-products
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become airborne. Legionnaire's disease, some pneumonias, anthrax, and
tuberculosis are airborne infectious diseases caused by bacteria.
[0005] Anthrax is an acute infectious disease caused by the spore-
forming bacterium Bacillus anthracis. It is most commonly found in hoofed
animals
but can also infect humans. The serious forms of human anthrax are inhalation
anthrax (often fatal), cutaneous anthrax, and intestinal anthrax. In October
2001,
four workers died from inhalation anthrax and an additional 13 developed
cutaneous or inhalation disease as a result of intentional terrorist activity.
Employers and workers are concerned about possible exposure to Bacillus
anthracis in the workplace.
[0006] Endotoxins are components of a bacterial cell. More precisely,
they are components of the outer membrane of some bacteria. Dangerous levels
of airborne endotoxins have been reported in numerous work environments,
including offices and laboratories. They can cause fever and malaise, changes
in
white blood cell counts, and respiratory and gastrointestinal problems.
[0007] There are over 100 000 known species of fungi. Microscopic
fungi include yeasts and molds. Most fungi produce spores that are carried by
the
air. The diameter of these spores varies from approximately 1 to 60 microns.
Most
substances containing carbon, abundant in indoor and outdoor environments, can
serve as nutrients for molds. Accumulation of humidity in the indoor
environment is
the most important factor to be controlled to limit fungal growth.
[0008] Some fungi can invade living cells, causing infectious diseases.
Several molds produce proteins and glycoproteins that are highly antigenic
i.e.
capable of producing an immune response, and can cause hypersensitivity
diseases or allergies in susceptible individuals. Practically all living
organisms
contain proteins, glycoproteins and polysaccharides with antigenic potential.
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Growing molds may additionally produce several volatile organic compounds,
some of which are at the origin of the frequently observed characteristic
moldy
odor.
[0009] Of all the hyper sensibility diseases, only hypersensitivity
pneumonitis allergic asthma, allergic rhinitis and allergic aspergillosis are
known as
resulting from exposure to airborne antigens.
[0010] Water reservoirs and air conditioning units cooling coils where
warm water condenses are good growth media for various bacteria fungi or
protozoa. Consequently, ventilation system components, particularly some types
of
humidifiers, can aerosolize droplets from water reservoirs and are therefore
of
special interest. Hypersensitivity pneumonitis has occurred in individuals
when
building humidification systems were contaminated.
[0011] It is now common knowledge that the energy efficient designs of
the 1970's resulted in the construction of tighter building envelopes having
improved insulation, low energy consuming ventilation and having no operable
windows. These designs have contributed to an increase in indoor pollutant
sources, since these pollutants are no longer sufficiently diluted with fresh
air.
Additionally, new building materials, products, and furnishing emit a
significant
number of hazardous chemicals into the air. The resulting situation results in
an
increase in contaminants circulating through the indoor environment, with
insufficient outside air being introduced to dilute these contaminants.
[0012] Indoor air quality (IAQ), is a complex issue, much more so than
any single environmental issue. There are hundreds of pollutants that effect
IAQ
and thousands of sources. Research reveals that more than 900 different
contaminants are present in indoor environments.
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[0013] If needs for comfort, health and well-being are not satisfied,
building occupants may begin to complain of symptoms which are associated with
poor IAQ. Headaches, burning and itching eyes, respiratory difficulties, skin
irritation, nausea, congestion, cough, sneezing, and fatigue are some of the
more
frequent complaints. Complaints of funny odors in the air are usually
indicative of
poor air quality.
[0014] An increasing percentage of the population is becoming more
sensitive to a number of chemicals in indoor air, each of which may occur at
very
low concentrations. The existence of this condition has been identified as
"Multiple
Chemical sensitivity" (MCS) and is currently the subject of chemical research.
[0015] According to the EPA, the effects of IAQ problems are often
non-specific symptoms rather than clearly defined illnesses. Although they can
be
vague, the symptoms seem generally worse after a day in the building (office
or
work place) and may altogether disappear when the occupant leaves the
building.
[0016] In light of these problems, the importance of efficiently purified
air, rid of biological contaminants, becomes readily understandable.
OBJECTS OF THE INVENTION
[0017] An object of the present invention is to provide an outwardly
projecting air purifier.
SUMMARY OF THE INVENTION
[0018] More specifically, according to an embodiment of the present
invention, there is provided a An outwardly projecting air purifier to be used
in
an air duct supporting a longitudinal airflow and comprising:
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a support to be positioned within the air duct;
a plurality of UV lamp assemblies longitudinally mounted to
said support; each of said UV lamp assemblies including a reflector having a
generally parabolic inner surface and a UV lamp so mounted to said reflector
that
said generally parabolic inner surface reflects UV radiation emitted by said
UV
lamp in a radial direction; and
a convex deflector element so mounted to said support that
the airflow is deflected over said UV lamp assemblies.
[0019] According to another aspect of the present invention, there is
provided an outwardly projecting air purifier to be positioned longitudinally
within an air duct supporting an airflow comprising:
a support;
a convex shaped deflector element so mounted to
said support as to be located upstream with respect to the airflow;
at Ic:ast two reflectors having a generally parabolic
inner surface mounted to said support; and
at least two UV lamps each being so mounted to a
corresponding reflector that UV radiation emitted by said lamps is reflected
in a
radial direction;
wherein each of said at least two reflectors is so mounted to said support
that
airflow is deflected by said convex shaped deflector element over said UV
lamps.
[0020] According to a third aspect of the present invention, there is
provided an outwardly projecting air purifier to be used in an air duct
supporting a
longitudinal airflow and comprising:
a plurality of adjacently interconnected UV lamp assemblies
each including
a reflector having a generally parabolic inner surface and an
outer surface so configured as to be interconnectable with the
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outer surface of a reflector of an adjacent UV lamp assembly;
and
a UV lamp so mounted to said reflector that said generally
parabolic inner surface reflects UV radiation emitted by said
UV lamp in a radial direction;
a convex deflector element so mounted to said reflectors that
the airflow is deflected over said UV lamp assemblies.
[0021] It is to be noted that the expression "air duct" is to be construed
in the present description and appended claims as meaning any passage designed
to guide ventilating air.
[0022] It is to be noted that the expression "plurality" is to be construed
in the present description and appended claims as meaning at least two.
[0023] It is to be noted that the expression "generally parabolic" is to be
construed in the present description and appended claims as meaning a
generally
concave cross-section that would adequately reflect incident radiation thereon
in a
generally radial direction.
[0024] Other objects, advantages and features of the present invention
will become more apparent upon reading of the following non-restrictive
description of preferred embodiments thereof, given by way of example only
with
reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In the appended drawings:
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[0026] Figure 1 is a perspective view illustrating an outwardly projecting
air purifier according to an embodiment of the present invention;
[0027] Figure 2 is an end view of the air purifier of Figure 1;
[0028] Figure 3 is a partially exploded view of the proximate end of the
air purifier of Figure 1;
[0029] Figure 4 is a cross-sectional view of an air duct in the direction
of the airflow and illustrating a series of air purifier as illustrated in
Figure 1;
[0030) Figure 5 is an enlarged portion of Figure 3;
[0031] Figure 6 is an end view similar to Figure 2 but illustrating an
outwardly projecting air purifier according to a second embodiment of the
present
invention;
[0032] Figure 7 is an end view similar to Figure 2 but illustrating an
outwardly projecting air purifier according to a third embodiment of the
present
invention; and
(0033] Figure 8 is an end view similar to Figure 2 but illustrating an
outwardly projecting air purifier according to a fourth embodiment of the
present
invention.
DESCRIPTION OF AN EMBODIMENT OF THE INVENTION
[0034] An outwardly projecting air purifier 10 according to a first
embodiment of the present invention is illustrated in Figures 1 to 3.
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[0035] Generally stated, the air purifier 10 is designed to be used within
air ducts and in other types of ventilation systems supporting a longitudinal
airflow
and to be positioned along the airflow, such that the airflow meets head-on
with a
convex shaped deflector element, deflecting the air in the vicinity of the
surface of
UV lamps which are positioned along the airflow. Therefore, a biological wall
is
created in the air duct.
[0036] As will be described in greater details hereinbelow, the air
purifier 10 comprises reflectors having a generally parabolic inner surface,
such
that essentially all of the UV radiation emitted by UV lamps positioned
therein is
reflected radially, such that air not directly coming into contact with the
lamps is
radiated with the maximum possible intensity.
[0037] In order to ensure an adequate air purification efficiency,
wherever required, several air purifiers in accordance with the present
invention
can be positioned within the air ducts or other ventilation systems.
[0038] Generally stated, the air purifier according to the present
invention is an apparatus comprising a plurality of UV lamp assemblies, each
including a germicidal lamp removably positioned within a reflector having a
generally parabolic inner surface. These lamp assemblies are so positioned
that a
cylindrical array of UV lamp assemblies is obtained. A convex shaped deflector
element is positioned at the proximate, or upstream, end of the air purifier.
The
apparatus is positioned against the airflow, such that the airflow meets head-
on
with the convex shaped deflector element, deflecting the air over the surface
of the
UV lamps, hence subjecting the air to UV radiation.
[0039] One skilled in the art will appreciate that an oxydizing/germicidal
lamp could also be used in the UV lamp assemblies.
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[0040] Generally, a preferred position of the air purifier in a ventilation
system is before the HVAC coil, after the filter, on the return side of the
coil. In this
preferred position, both the coil and the drainpan will be contaminant free.
The fact
that the air moves slower on the return side of the coil than on the supply
side,
means that the efficiency of the air purifier is higher when mounted in this
position,
and requires less units for the same killing percentage than if the
installation is on
the supply side of the coil. In most existing applications, the preferred
mounting is
not practical, as there is not enough room between the filter and the coil to
do the
installation. In these instances, the air purifier is mounted in the supply
duct after
the coil.
[0041] Turning now more specifically to the appended Figures 1 to 3,
an air purifier 10 comprising a cylindrical array of five UV tamp assemblies,
each
comprising a UV lamp 12 mounted to a respective reflector 14 via two or more
securing clamps 18 will be described.
[0042] As can be better seen from Figure 2, each reflector 14
comprises a generally parabolic inner surface 20, reflecting the UV radiation
emitted by the lamp 12 in an outward, radial, direction. The shape of the
inner
surface 20 and the position of the lamp 12 with respect to the inner surface
20 are
such that essentially all of the radiation is reflected outward. As will be
readily
understood by one skilled in the art, the reflector 14 and/or its inner
surface 20, is
advantageously made of a material that adequately reflects UV radiation such
as,
for example, aluminum.
[0043] Returning to Figure 1, the five UV lamp assemblies forming the
cylindrical array are mounted to a support 22, having a proximate end 24 and a
distal end 26, via mounting plates 27 and 28 (see Figures 1 and 3) and
mounting
fasteners 29 (see Figure 3). More specifically, the mounting plates 27 and 28
are
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mounted to the support 22 via fasteners 31 (Figure 3) and the lamp assemblies
are
mounted to the mounting plates 27 and 28 via the above-mentioned fasteners 29
[0044] The convex shaped deflector element 16 is mounted to the
proximate end 24 of the support 22, such that when the air purifier 10 is
positioned
within the air ducts or other ventilation system, opposite the airflow, the
airflow
meets head-on therewith and is deflected over the surface of the lamps 12 and
continues to flow along the length of the air purifier 10, as will be
discussed
hereinbelow.
(0045] Figure 4 is illustrative of a cross-sectional view of an air duct 30
or other ventilation system comprising a series of air purifier 10. An
enlarged
portion of this cross-sectional view is illustrated in Figure 5. As can be
appreciated
by one skilled in the art, the internal surface of the duct 30 is covered with
a
material that adequately reflects UV radiation such as, for example a layer of
aluminum 32.
[0046] Not shown in these figures is the frame required to maintain the
air purifiers 10 in their intended positions. It is believed that one skilled
in the art is
in a position to design such a frame
[0047] As can be seen from Figure 5, it will be understood by one
skilled in the art that the distance between adjacent air purifiers 10A and
10B may
be twice the distance between the air purifier 10A and the inside surface of
the
duct 30 while maintaining an essentially constant UV radiation across the
entire
cross-section of the duct 30.
(0048] It will also be understood by one skilled in the art that the length
and number of required air purifiers 10, as well as the distance separating
two
adjacent air purifiers 10, depend on many factors such as, for example, the
duct
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cross-section, the airflow speed. the expected level of contaminants, the
expected
percentage of destruction of the contaminant and the expected nature of the
contaminants. It is also to be noted that if the required length of UV lamps
is
greater than the lamps available, two or more air purifiers may be provided
end to
end.
[0049] It will be understood by one skilled in the art that the reflector
and/or its inner surface can be made of extruded aluminum, or any other
material
that would adequately reflect the incident radiation thereon in a generally
radial
direction.
[0050] The air purifier, in accordance with an embodiment of the
present invention, dramatically improves the air quality, more specifically
the
indoor air quality of buildings, by efficiently purifying and decontaminating
the air of
many harmful contaminants, whether from biological or other origin. The
generally
parabolic design of the inner surface 20 of the reflector 14 ensures that
essentially
all of the emitted UV radiation produced by the lamps is projected in an
outward,
radial, direction ensuring higher amounts of ultraviolet light traversing the
air. This
allows for the effective radiation of air not directly deflected by the
deflector
element.
[0051] Additionally, the convex design of the deflector element 16, is
both non-obtrusive to the airflow, and also ensures that the air is deflected
in the
vicinity of the surface of the lamps and continues to flow along the length of
the air
purifier more an improved efficiency of the assembly.
[0052] Turning briefly to Figure 6 of the appended drawings, an air
purifier 100 according to a second embodiment of the present invention will be
described. The air purifier 100 is very similar to the air purifier 10
illustrated in
Figures 1 to 5 but includes only four UV lamp assemblies 102a-102d mounted to
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slightly smaller mounting plates 104 (only one shown). One skilled in the art
will
understand that the number of UV lamp assemblies forming the air purifier is
not
critical to the operation of the air purifier and is chosen according to the
application
foreseen for the air purifier.
[0053] Turning now to Figure 7 of the appended drawings, an
outwardly projecting air purifier 200 according to a third embodiment of the
present
invention will be briefly described. Since the outwardly projecting air
purifier 200 is
very similar to the outwardly projecting air purifier 10 illustrated in
Figures 1 to 3,
only the differences between these outwardly projecting air purifiers will be
described hereinbelow.
[0054] The main difference between the air purifier 200 and the air
purifier 10 of Figures 1 to 3 is concerned with filler pieces 202a - 202e
positioned
between adjacent UV lamp assemblies. The purpose of these filler pieces is to
prevent air from going between adjacent UV lamp assemblies to thereby allow a
portion of the air to avoid being irradiated by the lamps.
[0055] As is apparent from Figure 7, the filler pieces 202a - 202e are so
shaped that they adequately cover the free space between adjacent UV lamp
assemblies.
[0056] The filler pieces 202a - 202e could be made of extruded
aluminum, for example. Of course, other materials and/or method of manufacture
could be used.
[0057] It is also to be noted that the length of the filler pieces can be
equivalent to the length of the UV lamp assemblies, but could also be
significantly
smaller. In the latter case, the filler pieces would advantageously be
positioned
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near the convex shaped deflector element 16 (not shown in this Figure) to
deflect
air out of the free space between the adjacent UV lamp assemblies.
[0058] The operation of the outwardly projecting air purifier 200 is as
described hereinabove with respect to the air purifier 10.
[0059] Finally, turning to Figure 8 of the appended drawings, an
outwardly projecting air purifier 300 according to a fourth embodiment of the
present invention will be described. Again, only the differences between the
outwardly projecting air purifier 300 and the other outwardly projecting air
purifiers
described hereinabove will be described.
[0060] The main difference between the air purifier 300 and the other
air purifiers described herein is concerned with the reflectors 302a - 302e
having
an outer surface 304 that is generally flat and that is designed to mate with
the
outer surface of an adjacent reflector to yield the same result as the filler
pieces of
Figure 7.
[0061) One will also understand that this mating of the external
surfaces of the reflectors 302 makes it possible to forego the use of the
central rod
22 and of the mounting plates 27 and 28 by interconnecting the reflectors via
fasteners 306. Of course, if this approach is taken, the deflector 308 is not
provided with a central aperture but is directly mounted to the reflectors 304
via
brackets 310 so configured and shaped as to interconnect the inner concave
surface of the deflector to the inner surface of the reflectors. Of course, an
aperture could be provided into the deflector should electrical wires have to
be
passed therethrough.
[0062] As will be understood to one skilled in the art, the length of the
UV lamp assemblies described hereinabove and illustrated in Figures 1 to 6
varies
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depending on the application intended for the air purifier. For example, 17
inches
(about 43 cm) long lamps could be used in a residential setting and 40, 50 or
60
inches (1.02 m, 1.27m or 1.52m) long lamps could be used in a commercial or
industrial setting.
[0063) Although the present invention has been described hereinabove
by way of preferred embodiments thereof, it can be modified, without departing
from the spirit and nature of the subject invention as defined in the appended
claims.
