U.S. patent application number 17/405903 was filed with the patent office on 2021-12-09 for photocatalytic filtration in vehicle hvac system.
This patent application is currently assigned to Calsonic Kansei North America, Inc.. The applicant listed for this patent is Calsonic Kansei North America, Inc.. Invention is credited to Gursaran Das Mathur, Silvia Denisse Vazquez Salazar, Scott Torok.
Application Number | 20210379528 17/405903 |
Document ID | / |
Family ID | 1000005787513 |
Filed Date | 2021-12-09 |
United States Patent
Application |
20210379528 |
Kind Code |
A1 |
Mathur; Gursaran Das ; et
al. |
December 9, 2021 |
PHOTOCATALYTIC FILTRATION IN VEHICLE HVAC SYSTEM
Abstract
A photocatalyst filtration system for a vehicle includes a
housing having an airflow path, and a filter configured to filter
air flowing in the airflow path, the filter having a first
photocatalyst and a second photocatalyst. The system further
includes a first ultraviolet (UV) light source disposed proximate
the filter and configured to energize the first photocatalyst, and
a second UV light source disposed proximate the filter and
configured to produce light having a shorter wavelength than light
produced by the first UV light source, and configured to energize
the second photocatalyst. One of the first photocatalyst or the
second photocatalyst is configured to remove odor from the air. The
other of the first photocatalyst or the second photocatalyst is
configured to remove bacteria from the air.
Inventors: |
Mathur; Gursaran Das;
(Farmington Hills, MI) ; Salazar; Silvia Denisse
Vazquez; (Farmington Hills, MI) ; Torok; Scott;
(Farmington Hills, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Calsonic Kansei North America, Inc. |
Farmington Hills |
MI |
US |
|
|
Assignee: |
Calsonic Kansei North America,
Inc.
Farmington Hills
MI
|
Family ID: |
1000005787513 |
Appl. No.: |
17/405903 |
Filed: |
August 18, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
16414967 |
May 17, 2019 |
|
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17405903 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60H 3/0658 20130101;
B01D 53/885 20130101; B60H 3/0608 20130101; B01D 2255/802 20130101;
B01D 46/0038 20130101; B01D 2257/708 20130101; B01D 2259/804
20130101; B01D 53/007 20130101; B01D 46/0028 20130101; B01D 2257/90
20130101; B60H 2003/0691 20130101; A61L 9/00 20130101; B60H 3/0085
20130101; B01D 2279/50 20130101; B60H 2003/0675 20130101; B01D
2257/91 20130101 |
International
Class: |
B01D 53/88 20060101
B01D053/88; B01D 46/00 20060101 B01D046/00; B01D 53/00 20060101
B01D053/00; B60H 3/00 20060101 B60H003/00; B60H 3/06 20060101
B60H003/06; A61L 9/00 20060101 A61L009/00 |
Claims
1. A filtration system for a vehicle, comprising: a housing having
an airflow path; a filter disposed in the housing and configured to
filter air flowing in the airflow path, the filter comprising a
first photocatalyst and a second photocatalyst proximate an
upstream surface of the filter; a UV-A light source disposed
proximate the upstream surface and configured to energize the first
photocatalyst; and a UV-C light source disposed proximate the
upstream surface and configured to produce light having a shorter
wavelength than light produced by the UV-A light source, and
configured to energize the second photocatalyst, wherein: the UV-A
light source emits UV-A light along a UV-A light field on the
upstream surface of the filter, the UV-C light source emits UV-C
light along a UV-C light field on the upstream surface of the
filter, and the UV-A light field and the UV-C light field overlap
and encompass an entirety of the upstream surface.
2. The filtration system of claim 1, wherein the first
photocatalyst and the second photocatalyst are the same and include
between 0.1 and 0.5 g/m.sup.2 of TiO.sub.2.
3. The filtration system of claim 1, wherein: the UV-A light source
comprises a plurality of UV-A lightbulbs; the UV-C light source
comprises a plurality of UV-C lightbulbs; and the UV-A lightbulbs
and the UV-C lightbulbs are disposed in a staggered arrangement
along the airflow path.
4. The filtration system of claim 1, wherein one of the first
photocatalyst or the second photocatalyst is configured to remove
odor from the air, and the other of the first photocatalyst or the
second photocatalyst is configured to remove bacteria from the
air.
5. The filtration system of claim 1, wherein the filter further
comprises a carbon layer configured to remove particulate from the
air.
6. The filtration system of claim 1, wherein the UV-A light source
and the UV-C light source are disposed upstream from the
filter.
7. The filtration system of claim 1, wherein the UV-A light source
is disposed a first offset distance away from the filter and the
UV-C light source is disposed a second offset distance away from
the filter different from the first offset distance.
8. The filtration system of claim 7, wherein: the housing
comprises: a forward wall opposing the filter; an upper surface
formed at an upper periphery of the forward wall; a lower surface
formed at a lower periphery of the forward wall; and an air inlet
formed at a side wall of the housing between the forward wall and
the filter; and one of the UV-A light source or the UV-C light
source is coupled to the forward wall and the other of the UV-A
light source or the UV-C light source is coupled to at least one of
the upper surface or the lower surface.
9. The filtration system of claim 8, wherein the UV-A light source
comprises a first lightbulb coupled to the upper surface and a
second lightbulb coupled to the lower surface.
10. The filtration system of claim 1, wherein the vehicle is a ride
sharing vehicle or an autonomous vehicle.
11. A filtration system for a vehicle, comprising: a housing; a
filter having a filter upstream surface and a photocatalyst
disposed proximate the filter upstream surface; and a plurality of
UV lightbulbs disposed in the housing upstream and offset from the
filter and configured to provide both UV-A and UV-C light to an
entirety of the filter upstream surface, wherein the photocatalyst
is configured to be energized by both the UV-A light and the UV-C
light.
12. The filtration system of claim 11, wherein the photocatalyst
includes between 0.1 and 0.5 g/m.sup.2 of TiO.sub.2.
13. The filtration system of claim 11, wherein the plurality of UV
lightbulbs comprises a plurality of UV-A lightbulbs and a plurality
of UV-C lightbulbs, and wherein the UV-A lightbulbs and the UV-C
lightbulbs are disposed in a staggered arrangement along an airflow
path through the housing.
14. The filtration system of claim 11, wherein the filter further
comprises a carbon layer configured to remove particulate from air
flowing through the filter.
15. The filtration system of claim 11, wherein: the housing
comprises: a forward wall opposing the filter; an upper surface
formed at an upper periphery of the forward wall; a lower surface
formed at a lower periphery of the forward wall; and an air inlet
formed at a side wall of the housing between the forward wall and
the filter; and a first lightbulb of the plurality of UV lightbulbs
is coupled to the forward wall and a second lightbulb of the
plurality of UV lightbulbs is coupled to at least one of the upper
surface or the lower surface.
16. A filtration system for a vehicle, comprising: a housing having
an airflow path; a filter disposed in the housing and configured to
filter air flowing through the housing, the filter comprising a
first photocatalyst and a second photocatalyst proximate an
upstream surface of the filter; a plurality of UV lightbulbs
disposed in the housing upstream and offset from the filter and
configured to provide both UV-A light and UV-C light to an entire
surface of the filter, wherein: the UV-A light is configured to
energize the first photocatalyst and the UV-C light is configured
to energize the second photocatalyst, and the plurality of UV
lightbulbs are disposed in a staggered arrangement along the
airflow path.
17. The filtration system of claim 16, wherein the first
photocatalyst and the second photocatalyst are the same and include
between 0.1 and 0.5 g/m.sup.2 of TiO.sub.2.
18. The filtration system of claim 16, wherein the plurality of UV
lightbulbs comprises: a plurality of UV-A lightbulbs configured to
emit the UV-A light along a UV-A light field; and a plurality of
UV-C lightbulbs configured to emit UV-C light along a UV-C light
field, wherein the UV-A light field and the UV-C light field
overlap.
19. The filtration system of claim 16, wherein the filter further
comprises a carbon layer configured to remove particulate from the
air.
20. The filtration system of claim 16, wherein: the housing
comprises: a forward wall opposing the filter; an upper surface
formed at an upper periphery of the forward wall; a lower surface
formed at a lower periphery of the forward wall; and an air inlet
formed at a side wall of the housing between the forward wall and
the filter; and a first lightbulb of the plurality of UV lightbulbs
is coupled to the forward wall and a second lightbulb of the
plurality of UV lightbulbs is coupled to at least one of the upper
surface or the lower surface.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] The present application is a Divisional of U.S. patent
application Ser. No. 16/414,967, filed May 17, 2019, the entire
disclosure of which is hereby incorporated by reference herein.
BACKGROUND
[0002] The present application relates generally to the field of
air filtration in vehicle heating, ventilation, and air
conditioning ("HVAC") systems and more specifically to using
different types of ultraviolet light and filters to remove
contaminants from air.
[0003] Currently, vehicles such as automobiles are regularly driven
by a driver without any passengers and the vehicle sits unoccupied
when the driver reaches his or her desired destination. However, as
ridesharing increases and self-driving capabilities improve, it is
expected that each vehicle is more likely to begin carrying
multiple passengers at a time as well as throughout the day. The
increase in the number and frequency of riders will also result in
the increase in the number of contaminants (e.g., viruses, odors,
particulate matter, etc.) entering the vehicle, which presents a
danger of transmitting the contaminants between the occupants.
Moreover, due to the confined space of an automobile, when compared
to mass transit alternatives (e.g., buses, trains, etc.), air
containing contaminants provided by one occupant is more likely to
be recirculated by a vehicle HVAC system throughout the cabin and
to the other occupants.
[0004] It is therefore advantageous to provide a vehicle HVAC
system, which removes more contaminants from air recirculated in
the vehicle.
SUMMARY
[0005] One embodiment relates to a filtration system for a vehicle,
including a housing having an airflow path, and a filter disposed
in the housing and configured to filter air flowing in the airflow
path, the filter having a first photocatalyst and a second
photocatalyst. The system further includes a first ultraviolet (UV)
light source comprising a plurality of UV-A lightbulbs disposed
proximate the filter and configured to energize the first
photocatalyst, and a second UV light source comprising a plurality
of UV-C lightbulbs disposed proximate the filter and configured to
produce light having a shorter wavelength than light produced by
the first UV light source, and configured to energize the second
photocatalyst. The UV-A lightbulbs and the UV-C lightbulbs are
arranged in alternating fashion in a lateral direction across the
housing. One of the first photocatalyst or the second photocatalyst
is configured to remove odor from the air. The other of the first
photocatalyst or the second photocatalyst is configured to remove
bacteria from the air.
[0006] Another embodiment relates to an HVAC system for a vehicle,
including a housing, an evaporator disposed in the housing, and a
filter having a filter upstream surface and an opposing filter
downstream surface, the filter disposed in the housing upstream
from the evaporator. The system further includes a plurality of UV
lightbulbs disposed in the housing upstream and offset from the
filter and configured to provide UV-A light and UV-C light to
substantially the entire filter upstream surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an HVAC system with photocatalytic filtration
according to an exemplary embodiment.
[0008] FIG. 2 is a cross-sectional view of a portion of the HVAC
system showing the arrangement of ultraviolet lights and a
filter.
[0009] FIG. 3 is a portion of the cross-sectional view of FIG. 2,
showing the placement of UV lightbulbs in the HVAC system.
DETAILED DESCRIPTION
[0010] Referring to FIG. 1, an HVAC system 100 is shown according
to an exemplary embodiment. The HVAC system 100 includes a blower
102, an evaporator 104 downstream from the blower 102, and a heater
106 (shown in FIG. 2) downstream from the evaporator 104. The
blower 102, evaporator 104, and heater 106 are disposed in a
housing 108 and define an airflow path flowing therethrough. For
example, the housing 108 may include a blower housing 110
containing the blower 102 therein, an evaporator housing 112
containing the evaporator 104 therein, and a heater housing 114
containing the heater 106 therein. An HVAC inlet 116 is formed at
an upstream end of the housing 108 (e.g., at an upstream end of the
blower housing 110) and is configured to supply air to the blower
102. An HVAC outlet 118 is formed at a downstream end of the
housing 108 (e.g., at a downstream end of the heater housing 114)
and is configured to output heated or cooled air from the HVAC
system 100 to one or more portions of a passenger compartment of a
vehicle.
[0011] The HVAC system 100 further includes a filter 120 disposed
in the housing 108. For example, as shown in FIG. 1, the filter 120
is disposed in the evaporator housing 112 upstream from both the
evaporator 104 and the heater 106. The filter 120 is shown
downstream from the blower 102, although it should be understood
that the filter 120 may be placed in other locations within or
outside of the housing 108, such that the filter 120 is upstream
from both the evaporator 104 and the heater 106. In this
configuration, substantially all of the air received in the blower
102 and passed through the HVAC system 100 is required to flow
through the filter 120, ensuring complete and efficient filtration
of the air recirculating in a vehicle. According to other exemplary
embodiments, in some configurations, air may pass downstream from
the filter 120 directly to the heater 106, bypassing the evaporator
104. In this configuration, substantially all of the air still
passes through the filter 120 first, before passing through the
heater 106.
[0012] A plurality of ultraviolet (UV) lightbulbs 126 (i.e., lamps)
are disposed in the housing 108, proximate and upstream from the
filter 120. For example, the filter 120 defines a filter upstream
surface 122 (i.e., an upstream end, a filter first end, etc.) and
an opposing filter downstream surface 124 (i.e., a downstream end,
a filter second end, etc.) and the plurality of UV lightbulbs 126
are disposed proximate the filter upstream surface 122. In this
configuration, the UV lightbulbs 126 are disposed in the evaporator
housing 112, although according to other exemplary embodiments, the
UV lightbulbs 126 may be disposed in other locations within or
outside of the housing 108, such that the UV lightbulbs 126 are
upstream from the filter 120. According to another exemplary
embodiment, the UV lightbulbs 126 may be disposed downstream from
the filter 120, proximate the filter downstream surface 124 and
upstream from the evaporator 104. According to yet another
exemplary embodiment, the plurality of UV lightbulbs 126 may
include at least one UV lightbulb 126 upstream from the filter 120
and at least one UV lightbulb 126 downstream from the filter
120.
[0013] It should be appreciated that the filter 120 and the UV
lightbulbs 126 are positioned in the housing 108 upstream from the
evaporator 104. Specifically, when the evaporator 104 operates in
the HVAC system 100 in order to cool down the air passing through
the evaporator 104, water condensation forms on the surface of the
evaporator 104 and increases the humidity in the air output from
and passing downstream from the evaporator 104 and into the
passenger compartment of the vehicle. If the UV lightbulbs 126 were
disposed close to or downstream from the evaporator 104,
condensation could form on the UV lightbulbs 126, which would
redirect portions of the UV light passing through the condensation
and could result in portions of the filter 120 that is not directly
contacted by UV light output from the UV lightbulbs 126, thereby
reducing the effectiveness of the photocatalytic filtration through
the filter 120.
[0014] Referring now to FIG. 2, a cross-section view of a portion
of the HVAC system 100 is shown according to an exemplary
embodiment. Specifically, the evaporator housing 112 and the heater
housing 114 are shown with the filter 120 and the plurality of UV
lightbulbs 126 disposed upstream from the evaporator 104 and the
heater 106. The filter 120 may be a two-part filter, including both
a titanium oxide (e.g., titanium dioxide or TiO.sub.2) and carbon,
and is configured to kill and remove viruses, bacteria, and
volatile organic compounds (VOCs), such as odors, mold, or mildew
from the air circulating in the vehicle. For example, FIG. 2 shows
the filter 120 having a first layer 128 (i.e., titanium oxide
layer, upstream layer, VOC layer, etc.) at or proximate the filter
upstream surface 122, and a second layer 130 (i.e., substrate,
downstream layer, carbon layer, high-efficiency particulate air or
HEPA layer, etc.) at or proximate the filter downstream surface
124. The second layer 130 may serve as a substrate for the first
layer 128, such that the first layer 128 is disposed directly on
the second layer 130. In this configuration, the air passing
through the filter 120 is received at the first layer 128 and then
passes through the second layer 130 and is output from the filter
downstream surface 124 to one or both of the evaporator 104 and the
heater 106. According to other exemplary embodiments, the filter
120 may be integrally formed with both the carbon and TiO.sub.2
being included as a single layer for filtering multiple types of
particulates out of an air stream.
[0015] According to an exemplary embodiment, the first layer 128
includes a first photocatalyst, such as TiO.sub.2. For example, the
first layer 128 may include between approximately 0.1 and 0.5
g/m.sup.2 of TiO.sub.2 across substantially an entire surface area
of the first layer 128 (e.g., at the filter upstream surface 122).
It should be appreciated that an increase in the mass of TiO.sub.2
per unit area (i.e., surface area density) increases resistance
through the first layer 128 and, therefore, if the power of the
blower 102 increases, then the surface area density of TiO.sub.2 in
the first layer 128 may be increased. During operation of the HVAC
system 100, the UV lightbulbs 126 output UV light, which interacts
with the TiO.sub.2 surface of the first layer 128 through a process
known as photocatalysis to generate electrons on the surface of the
first layer 128. The electrons on the surface of the first layer
128 interact with water (H.sub.2O) molecules in the air, breaking
the molecules up into hydroxyl (OH) radicals, which are highly
reactive and short-lived forms of hydroxide ions (OH.sup.-). The
hydroxyl radicals then interact with viruses, bacteria, and VOCs,
which are each carbon-based complex molecules, during which the
radicals break the complex molecules down into water and carbon
dioxide (CO.sub.2) constituents.
[0016] According to an exemplary embodiment, the plurality of UV
lightbulbs 126 includes at least one UV-A lightbulb 132 (e.g., a
first UV light source) and at least one UV-C lightbulb 134 (e.g., a
second UV light source). Each UV-A lightbulb 132 is configured to
produce light having a wavelength of between approximately 315 nm
and 420 nm. The UV-A lightbulbs 132 may be U-shaped or fluorescent
lightbulbs or have other shapes or types of lightbulbs and are
configured to output UV-A light. The UV-A lightbulbs 132 may have a
power supply terminal at one of an upper end or a lower end for
providing power thereto. Each UV-C lightbulb 134 is configured to
produce light having a wavelength of between approximately 100 nm
and 280 nm. According to an exemplary embodiment, the UV lightbulbs
126 operate at approximately 12V and 100 W, with a heat flux of
between approximately 30 W/m.sup.2 and 40 W/m.sup.2. FIGS. 1 and 2
show two (e.g., a plurality, a pair, etc.) UV-A lightbulbs 132 and
two UV-C lightbulbs 134, although it should be appreciated that
more or fewer UV-A lightbulbs 132 and/or UV-C lightbulbs 134 may be
included in the HVAC system 100 upstream from the filter 120 or in
other portions of the HVAC system 100.
[0017] According to an exemplary embodiment, the UV-A lightbulbs
132 are configured to transmit UV-A light to the first
photocatalyst, which forms a portion of the first layer 128 to
reduce or eliminate VOCs from the air. Specifically, UV-A light
energizes the first photocatalyst as described above, to generate
the hydroxyl radicals. The UV-A lightbulbs 132 are configured to
break down the VOCs upstream from the second layer 130 (e.g., in
the first layer 128 or upstream from the first layer 128), such
that at least a portion of the constituent parts of the VOCs do not
interact with carbon in the second layer 130. After passing the air
through the first layer 128 of the filter 120, the air output from
the HVAC system 100 into the vehicle contains fewer or no VOCs,
reducing or eliminating any odor within the vehicle. This
configuration can also be used with a vehicle's air intake, such as
with the HVAC inlet 116 configured to receive air from outside the
vehicle. In this configuration, the HVAC system 100 prevents the
introduction of VOCs into the vehicle in the first place.
[0018] Similar to the UV-A lightbulbs 132, the UV-C lightbulbs 134
are configured to transmit UV-C light to the first layer 128 to
reduce or eliminate bacteria and/or viruses from the air. The first
layer 128 further includes a second photocatalyst, which may be the
same as or different from the first photocatalyst and is configured
to be energized by UV-C light. Specifically, the interaction of the
UV-C and the second photocatalyst in the first layer 128 generates
hydroxyl radicals, which breaks down the bacteria and/or viruses
into mostly water and carbon dioxide, killing and removing the
bacteria and/or viruses from circulation and protecting occupants
in the vehicle. Advantageously, when the HVAC system 100 is used in
a vehicle with multiple occupants, by constantly recirculating the
air through the HVAC system 100, the likelihood of transmitting a
virus or bacteria between passengers can be reduced. In this
situation, the HVAC system 100 may operate an entire time that the
vehicle is occupied to most effectively remove contaminants from
the air. Notably, the blower 102 continues cycling air through the
HVAC system 100 and through the filter 120 activated by the UV
lightbulbs 126, even if the evaporator 104 and/or the heater 106
are not operating to affect the temperature inside the vehicle.
According to another exemplary embodiment, the filtration aspects
of the HVAC system 100 may be selectively engaged based on a
condition of an occupant (e.g., known disease symptoms) to operate
the UV lightbulbs 126 to filter the air with the filter 120 using
photocatalysis.
[0019] Further, the HVAC system 100 may be operated in the vehicle
for a period of time between uses by two different passengers. The
vehicle may be a ride sharing vehicle, an autonomous vehicle, or
another high occupancy transportation system (e.g., a taxi, a bus,
a train, an airplane, etc.). The passengers may be positioned
within the vehicle to face one another, which can increase the risk
of spreading germs and viruses (e.g., the flu). In one example, a
first passenger (i.e., occupant) may depart the vehicle. Then, the
HVAC system 100 operates to purify the air currently in the vehicle
before a second passenger enters the vehicle, thereby protecting
future occupants from viruses or bacteria of earlier passengers.
The HVAC system 100 may operate for a pre-determined amount of time
required to completely circulate the volume of the passenger
compartment. For example, the HVAC system 100 may operate for
approximately 10 minutes, 15 minutes, 30 minutes or any other
amount of time before a passenger enters the vehicle. In some
implementations, an operating time for the HVAC system 100 after an
earlier passenger departs the vehicle may be optimized based on UV
settings or other parameters for the HVAC system 100 such as UV
heat flux, TiO2 loading, and air flow rate. Among other benefits,
the UV light emitted from the HVAC system 100 (e.g., UV light at a
wavelength within a range between 100 and 480 nm or any other
suitable range) will kill bacteria, viruses, mold and other
pathogens contained within the vehicle cabin. The UV light will
also breakdown VOCs such as cigarette smoke.
[0020] Referring still to FIG. 2, at least a portion of the second
layer 130 of the filter 120 is formed from carbon. The second layer
130 may be configured to interact with portions of VOCs that are
not broken down by the UV-A lightbulbs 132 to reduce odor output
from the HVAC system 100 and being recirculated in the vehicle.
According to an exemplary embodiment, the second layer 130 may be
configured to filter out particles that are approximately 0.3
microns or greater with approximately 99.97% efficiency.
[0021] It should be appreciated that over time, particulate may
build up on one or both of the layers 128, 130 in the filter 120,
reducing the surface area available for passing air therethrough.
This particle buildup reduces the operational efficiency of the
HVAC system 100, requiring higher blower 102 output for the same
volume air flow. As shown in FIG. 2, a first side wall 136 (i.e., a
side wall) of the housing 108 (e.g., in the evaporator housing 112)
defines a filter opening 138 therein and the HVAC system 100
includes a filter cover 140 disposed in the filter opening 138 and
holding the filter 120 in place while sealing the housing 108. The
filter cover 140 may further seal against the filter 120 to prevent
air from passing around the filter 120, in a space between the
filter 120 and the filter cover 140, rather than through the filter
120. According to another exemplary embodiment, the filter 120 may
include the first layer 128 and not include the second layer 130 in
order to prevent the buildup of particulate within the filter 120
and only purify the air through photocatalysis.
[0022] The HVAC system 100 may further include a first sensor 142
(i.e., an upstream sensor) disposed in the housing 108 upstream
from the filter 120 and a second sensor 144 (i.e., a downstream
sensor) disposed in the housing 108 downstream from the filter 120.
For example, the first sensor 142 may be disposed in the evaporator
housing 112 proximate the filter upstream surface 122 and
configured to measure a first pressure P.sub.1 (i.e., an upstream
pressure) or a volume flow rate of air at the filter upstream
surface 122. The second sensor 144 may be disposed in the
evaporator housing 112 proximate the filter downstream surface 124
and upstream from the evaporator 104. The second sensor 144 is
configured to measure a second pressure P.sub.2 (i.e., a downstream
pressure) or a volume flow rate of air at the filter downstream
surface 124. The first and second sensors 142, 144 are connected to
a processor 146 and are configured to send a signal to the
processor 146 indicating the first pressure P.sub.1 and the second
pressure P.sub.2, respectively.
[0023] A pressure differential is defined as a difference between
the second pressure P.sub.2 and the first pressure P.sub.1 and is
configured to represent or measure an amount of particle buildup on
one or both of the first or second layers 128, 130 of the filter
120. Notably, the processor 146 receives the first pressure P.sub.1
and the second pressure P.sub.2 from the first and second sensors
142, 144, respectively and calculates the pressure differential
based on these measurements. When the filter 120 is first installed
in the HVAC system 100, the pressure differential may be
approximately zero or very small. As particulate matter builds up
in the filter 120 the pressure differential increases. A
pre-determined threshold pressure is provided to the processor 146
and when the pressure differential exceeds the threshold pressure,
the processor 146 outputs a signal (e.g., a light indicator, a
message, etc.) either wired or wirelessly to a user or maintenance
professional that the filter 120 needs to be changed. A user may
then remove the filter cover 140 from the housing 108 and withdraw
the used filter 120 from the housing 108 through the filter opening
138, followed by inserting a new filter 120 through the filter
opening 138 and resealing the housing 108 by covering and sealing
the filter opening 138 with the filter cover 140. According to
another exemplary embodiment, signal may be configured to
illuminate after a pre-determined time period, indicating a need to
change the filter 120.
[0024] Referring still to FIG. 2, the UV lightbulbs 126, shown as
UV-A lightbulbs 132 and UV-C lightbulbs 134, are arranged according
to an exemplary embodiment. The evaporator housing 112 includes the
first side wall 136 and an opposing second side wall 137. The
filter 120 and the evaporator 104 each extend laterally across the
evaporator housing 112 from the first side wall 136 to the second
side wall 137. The housing 108 further includes a forward wall 148
(i.e., a main wall) upstream from and opposing filter upstream
surface 122, and extending from the second side wall 137 toward the
blower housing 110. An air inlet 149 is formed in the first side
wall 136, proximate an upstream end of the evaporator housing 112,
between the forward wall 148 and the filter 120.
[0025] The UV lightbulbs 126 extend substantially vertically and
parallel to each other within the housing 108 as well as
substantially parallel to the filter 120. Referring now to FIGS. 2
and 3, the UV lightbulbs 126 include a first lightbulb 150 and a
second lightbulb 152 offset from the filter upstream surface 122 in
a longitudinal direction, substantially perpendicular to the filter
upstream surface 122. For example, the first lightbulb 150 is
disposed a first offset distance OD.sub.1 in the longitudinal
direction, away from the filter upstream surface 122. Similarly,
the second lightbulb 152 is disposed a second offset distance
OD.sub.2 in the longitudinal direction, away from the filter
upstream surface 122. According to an exemplary embodiment, the
first offset distance OD.sub.1 and the second offset distance
OD.sub.2 may be substantially the same, such that the first UV
lightbulb 150 is aligned with the second UV lightbulb 152 in a
lateral direction, widthwise across the evaporator housing 112
between the first and second side walls 136, 137. According to
another exemplary embodiment, the first offset distance OD.sub.1
may be different from (e.g., greater or lesser than) the second
offset distance OD.sub.2.
[0026] Referring still to FIGS. 2 and 3, the first lightbulb 150 is
disposed proximate and spaced apart from the first side wall 136 in
the lateral direction (e.g., parallel to the filter upstream
surface 122) by a first lateral distance LD.sub.1. Similarly, the
second lightbulb 152 is spaced apart from the first side wall 136
in the lateral direction by a second lateral distance LD.sub.2,
which is greater than the first lateral distance LD.sub.1, such
that the second lightbulb 152 is disposed closer to the second side
wall 137 than the first lightbulb 150. It should be appreciated
that the second lightbulb 152 is disposed proximate but spaced
apart from the second side wall 137.
[0027] The UV lightbulbs 126 further include a third lightbulb 154
and a fourth lightbulb 156 offset from the filter upstream surface
122 in the longitudinal direction. As shown in FIG. 2, the third
and fourth lightbulbs 154, 156 are disposed against the forward
wall 148, although according to other exemplary embodiments, the
forward wall 148 may have other arrangements, such that one or both
of the third and fourth lightbulbs 154, 156 are spaced apart from
the forward wall 148.
[0028] The third lightbulb 154 is disposed a third offset distance
OD.sub.3 in the longitudinal direction, away from the filter
upstream surface 122. Similarly, the fourth lightbulb is disposed a
fourth offset distance OD.sub.4 in the longitudinal direction, away
from the filter upstream surface 122. As shown in FIG. 2, the third
offset distance OD.sub.3 may be greater than one or both of the
first offset distance OD.sub.1 and the second offset distance
OD.sub.2, such that the third lightbulb 154 is disposed further
away from the filter upstream surface 122 than one or both of the
first and second lightbulbs 150, 152. The fourth offset distance
OD.sub.4 may be less than one or both of the first offset distance
OD.sub.1 and the second offset distance OD.sub.2, such that the
fourth lightbulb 156 is disposed closer to the filter upstream
surface 122 than one or both of the first and second lightbulbs
150, 152. Similarly, the fourth offset distance OD.sub.4 is less
than the third offset distance OD.sub.3, such that the fourth
lightbulb 156 is closer to the filter upstream surface 122 than the
third lightbulb 154.
[0029] According to other exemplary embodiments, the third and
fourth lightbulbs 154, 156 may be disposed in other positions
relative to the first and second lightbulbs 150, 152. For example,
the third offset distance OD.sub.3 may be less than one or both of
the first offset distance OD.sub.1 and the second offset distance
OD.sub.2, such that the third lightbulb 154 is disposed closer to
from the filter upstream surface 122 than one or both of the first
and second lightbulbs 150, 152. Similarly, the fourth offset
distance OD.sub.4 may be greater than one or both of the first
offset distance OD.sub.1 and the second offset distance OD.sub.2,
such that the fourth lightbulb 156 is disposed further away from
the filter upstream surface 122 than one or both of the first and
second lightbulbs 150, 152.
[0030] The third lightbulb 154 is spaced apart from the first side
wall 136 in the lateral direction (e.g., parallel to the filter
upstream surface 122) by a third lateral distance LD.sub.3. The
third lateral distance LD.sub.3 is greater than the first lateral
distance LD.sub.1 and less than the second lateral distance
LD.sub.2, such that the third lightbulb 154 is disposed laterally
between the first and second lightbulbs 150, 152 and is configured
to provide light between the first and second lightbulbs 150, 152
directly to the filter upstream surface 122. Similarly, the fourth
lightbulb 156 is spaced apart from the first side wall 136 in the
lateral direction by a fourth lateral distance LD.sub.4, which is
greater than the second lateral distance LD.sub.2, such that the
fourth lightbulb 156 is disposed laterally between the second
lightbulb 152 and the second side wall 137. It should be
appreciated that the second lightbulb 152 is disposed proximate but
spaced apart from the second side wall 137. It should further be
noted that in the configuration shown in FIG. 2, the UV lightbulbs
126 are shown alternating (i.e., arranged in an alternating
fashion) between UV-A lightbulbs 132 and UV-C lightbulbs 134 in the
lateral direction.
[0031] According to other exemplary embodiments, the third lateral
distance LD.sub.3 may be less than the first lateral distance
LD.sub.1, such that the third lightbulb 154 is disposed laterally
between the first side wall 136 and the first lightbulb 150.
Similarly, the fourth lateral distance LD.sub.4 may be greater than
the first lateral distance LD.sub.1 and less than the second
lateral distance LD.sub.2, such that the fourth lightbulb 156 is
disposed laterally between the first and second lightbulbs 150, 152
and is configured to provide light between the first and second
lightbulbs 150, 152 directly to the filter upstream surface
122.
[0032] As shown in FIG. 2, the first lightbulb 150 emits UV-A light
along a first light field 160 downstream toward the filter upstream
surface 122. Similarly, the second lightbulb 152 emits UV-A light
along a second light field 162 downstream toward the filter
upstream surface 122. The first light field 160 extends directly to
the filter upstream surface 122 at the first side wall 136 and at
least partway toward the second side wall 137. The second light
field 162 extends directly to the filter upstream surface 122 at
the second side wall 137 and at least partway toward the first side
wall 136, such that the first light field 160 and the second light
field 162 overlap on at least a portion of the filter upstream
surface 122. In this configuration, UV-A light is applied directly
to substantially the entire filter upstream surface 122 without
requiring reflection of the light within the housing 108. It should
be appreciated that the fourth lightbulb 156 is positioned in the
evaporator housing 112, such that the fourth lightbulb 156 is not
between the second lightbulb 152 and the filter upstream surface
122 at the second side wall 137 and therefore does not interfere
with providing UV-A light directly to the entire filter upstream
surface 122.
[0033] Similar to the first and second lightbulbs 150, 152, the
third lightbulb 154 emits UV-C light along a third light field 164
downstream toward the filter upstream surface 122 and the fourth
lightbulb 156 emits UV-C light along a fourth light field 166
downstream toward the filter upstream surface 122. The third light
field 164 extends directly to the filter upstream surface 122 at
the first side wall 136 and at least partway toward the second side
wall 137. The fourth light field 166 extends directly to the filter
upstream surface 122 at the second side wall 137 and at least
partway toward the first side wall 136, such that the third light
field 164 and the fourth light field 166 overlap on at least a
portion of the filter upstream surface 122. For example, the third
light field 164 and the fourth light field 166 may overlap on a
portion of the filter upstream surface 122 directly downstream from
the second lightbulb 152.
[0034] In this configuration, UV-C light is applied directly to
substantially the entire filter upstream surface 122 without
requiring reflection within the housing 108. It should be
appreciated that the second offset distance OD.sub.2 is provided,
such that second lightbulb 152 is positioned in the evaporator
housing 112 far enough away from the filter upstream surface 122 to
allow both the third light field 164 and the fourth light field 166
to overlap on the filter upstream surface 122. In other words, the
second lightbulb 152 is not disposed between any portion of the
filter upstream surface 122 and at least one of the third or fourth
lightbulbs 154, 156. Similarly, the first offset distance OD.sub.1
is provided, such that the first lightbulb 150 is positioned in the
evaporator housing 112 far enough away from the filter upstream
surface 122 to allow the third light field 164 to directly contact
the filter upstream surface 122 at the first side wall 136. In
other words, the first lightbulb 150 is not disposed between the
third lightbulb 154 and the filter upstream surface 122 at the
first side wall 136.
[0035] As provided in FIG. 2, it should be appreciated that due to
the staggered arrangement of the UV lightbulbs 126, UV-A light is
provided from at least one of the first or second lightbulbs 150,
152 directly to substantially the entire filter upstream surface
122 and UV-C light is provided from at least one of the third or
fourth lightbulbs 154, 156 directly to substantially the entire
filter upstream surface 122. While the first and second lightbulbs
150, 152 are shown as UV-A lightbulbs 132, it should be understood
that according to other exemplary embodiments, one or both of the
first and second lightbulbs 150, 152 may be UV-C lightbulbs 134,
configured to output UV-C light. Further, while third and fourth
lightbulbs 154, 156 are shown as UV-C lightbulbs 134, it should be
understood that according to other exemplary embodiments, one or
both of the third and fourth lightbulbs 154, 156 may be UV-A
lightbulbs 132, configured to output UV-A light. According to yet
other exemplary embodiments, one or more of the UV lightbulbs 126
may be configured to output a different wavelength of light.
[0036] Referring again to FIG. 1, the housing 108 is shown having a
lower surface 168 (i.e., a lower wall) at a lower periphery of the
forward wall 148 and an opposing upper surface 170 (i.e., an upper
wall) at an upper periphery of the forward wall 148. It should be
appreciated that a portion of the evaporator housing 112 is shown
broken away to show the UV lightbulbs 126, the filter 120 and the
evaporator 104, and that the upper surface 170 of the housing 108
includes a portion of the evaporator housing 112 between the blower
housing 110 and the heater housing 114. According to an exemplary
embodiment, at least one of the UV lightbulbs 126 may be inserted
substantially vertically through one of the lower surface 168 or
the upper surface 170 of the housing 108 into the heater housing
114. The UV lightbulbs 126 may then be coupled (i.e., fixed) to one
or both of the lower surface 168 and/or the upper surface 170. In
this configuration, the UV lightbulbs 126 may be accessible for
replacement from outside the housing 108 without disassembling the
housing 108. According to other exemplary embodiments, at least a
portion of the evaporator housing 114 or other portion of the
housing 108 may be removable to provide access to the UV lightbulbs
126. According to another exemplary embodiment, the UV lightbulbs
126 may be electrically coupled externally to the housing 108 to a
power source.
[0037] Further, as shown in FIGS. 1 and 2, the UV lightbulbs 126
are shown in a substantially vertical orientation. However, it
should be understood that according to other exemplary embodiments
the UV lightbulbs 126 may be arranged in a substantially horizontal
direction. In other words, the lateral direction may be defined
height wise across the evaporator housing 112 between the lower
surface 168 and the upper surface 170. In this configuration, the
lateral distances (e.g., the first lateral distance LD.sub.1, etc.)
for each of the UV lightbulbs 126 may be measured relative to one
of the lower surface 168 or the upper surface 170. In the
horizontal orientation, the UV lightbulbs 126 are disposed
substantially parallel to the lower surface 168 and/or the upper
surface 170 and are substantially perpendicular to the first side
wall 136 and the second side wall 137.
[0038] According to another exemplary embodiment, the UV lightbulbs
126 may be arranged in other orientations, such that the UV
lightbulbs 126 are substantially parallel to each other and/or the
filter upstream surface 122. According to yet another exemplary
embodiment, the UV lightbulbs 126 may include more or fewer than
two UV-A lightbulbs 132 and/or two UV-C lightbulbs 134, such that
substantially the entire filter upstream surface 122 is exposed
directly to both UV-A light and UV-C light.
[0039] While FIGS. 1 and 2 show the UV lightbulbs 126 disposed in
the evaporator housing 112 upstream from the filter 120, according
to another exemplary embodiment, one or more of the UV lightbulbs
126 may be disposed downstream from the filter 120. For example,
the UV lightbulbs 126 may be disposed between the filter downstream
surface 124 and the evaporator 104 and are configured to transmit
UV-A and/or UV-C light directly to the filter downstream surface
124. In this configuration, the filter 120 may be arranged with the
first layer 128 still disposed upstream from the second layer 130
or the filter 120 may be flipped, such that the first layer 128 is
disposed downstream from the second layer 130, such that the UV
lightbulbs 126 transmit UV light from downstream of the filter 120
to directly on the first layer 128 at the filter downstream surface
124. In this configuration, the offset distances (e.g., the first
offset distance OD.sub.1, etc.) for each of the UV lightbulbs 126
may be measured from the filter downstream surface 124 in the
downstream longitudinal direction (e.g., perpendicular to the
filter downstream surface 124).
[0040] According to yet another exemplary embodiment, UV lightbulbs
126 may be disposed both upstream from and downstream from the
filter 120. For example, at least one UV-A lightbulb 132 (e.g.,
both UV-A lightbulbs 132) may be disposed upstream from the filter
120 and at least one UV-C lightbulb 134 (e.g., both UV-C lightbulbs
134) may be disposed downstream from the filter 120. Similarly,
according to another exemplary embodiment, at least one UV-C
lightbulb 134 (e.g., both UV-C lightbulbs 134) may be disposed
upstream from the filter 120 and at least one UV-A lightbulb 132
(e.g., both UV-A lightbulbs 132) may be disposed downstream from
the filter 120. According to yet another exemplary embodiment at
least one UV-A lightbulb 132 and at least one UV-C lightbulb 134
may be disposed both upstream from and downstream from the filter
120, such that both UV-A and UV-C light is transmitted directly to
both the filter upstream surface 122 and the filter downstream
surface 124.
[0041] It should further be appreciated that the HVAC system 100
may be installed in vehicles with various types of powertrains. For
example, the HVAC system 100 may be installed in an electric
vehicle ("EV"), a hybrid-electric vehicle ("HEV"), a vehicle with
an internal combustion engine ("ICE") with or without a start-stop
feature, or other powertrains. Further, it should be appreciated
that an existing HVAC system in a vehicle may be retrofit by
installing the filter 120 and the UV lightbulbs 126 in the existing
HVAC system in any of the configurations described in this
application.
[0042] As utilized herein, the terms "approximately," "about,"
"substantially," and similar terms are intended to have a broad
meaning in harmony with the common and accepted usage by those of
ordinary skill in the art to which the subject matter of this
disclosure pertains. It should be understood by those of skill in
the art who review this disclosure that these terms are intended to
allow a description of certain features described and claimed
without restricting the scope of these features to the precise
numerical ranges provided. Accordingly, these terms should be
interpreted as indicating that insubstantial or inconsequential
modifications or alterations of the subject matter described and
claimed are considered to be within the scope of this disclosure as
recited in the appended claims.
[0043] It should be noted that the term "exemplary" as used herein
to describe various embodiments is intended to indicate that such
embodiments are possible examples, representations, and/or
illustrations of possible embodiments (and such term is not
intended to connote that such embodiments are necessarily
extraordinary or superlative examples).
[0044] The terms "coupled," "connected," and the like as used
herein mean the joining of two members directly or indirectly to
one another. Such joining may be stationary (e.g., permanent) or
moveable (e.g., removable or releasable). Such joining may be
achieved with the two members or the two members and any additional
intermediate members being integrally formed as a single unitary
body with one another or with the two members or the two members
and any additional intermediate members being attached to one
another.
[0045] References herein to the position of elements (e.g., "top,"
"bottom," "above," "below," etc.) are merely used to describe the
orientation of various elements in the FIGURES. It should be noted
that the orientation of various elements may differ according to
other exemplary embodiments, and that such variations are intended
to be encompassed by the present disclosure.
[0046] It is to be understood that although the present invention
has been described with regard to preferred embodiments thereof,
various other embodiments and variants may occur to those skilled
in the art, which are within the scope and spirit of the invention,
and such other embodiments and variants are intended to be covered
by corresponding claims. Those skilled in the art will readily
appreciate that many modifications are possible (e.g., variations
in sizes, dimensions, structures, shapes and proportions of the
various elements, values of parameters, mounting arrangements, use
of materials, colors, orientations, manufacturing processes, etc.)
without materially departing from the novel teachings and
advantages of the subject matter described herein. For example, the
order or sequence of any process or method steps may be varied or
re-sequenced according to alternative embodiments. Other
substitutions, modifications, changes and omissions may also be
made in the design, operating conditions and arrangement of the
various exemplary embodiments without departing from the scope of
the present disclosure.
* * * * *