FIELD OF THE INVENTION
[0001] The invention relates to a wearable air purification device.
BACKGROUND OF THE INVENTION
[0002] Breathing masks are well-known for outdoor activities, such as cycling and walking
in towns and cities. They are used to lessen risks associated with air pollution.
[0003] Traditional face masks tend to cover the nose and mouth with a filter secured by
a tight strap that secures around the ears. Such masks can provide relatively effective
filtration, but can cause discomfort to the wearer, in terms of both breathing and
wearingrelated discomfort.
[0004] In order to deliver effective filtration performance, masks tend to make breathing
more difficult for the wearer. Moreover, the tight-fitting nature of such masks can
lead to red marks being left on the face. Such masks can also risk spoiling make-up
that has been applied to the wearer's face prior to wearing the mask.
[0005] A further key disadvantage to such masks is their propensity to disrupt normal communication
and interfere with social engagement due to obscuring the wearer's facial features.
Covering one's face with a mask can be considered by some to be impolite.
[0006] To enhance user comfort, it would be desirable to control temperature of the filtered/purified
air supplied for the user to breathe. However, certain practical challenges have been
encountered in achieving such temperature control, particular in view of the need
to also purify the air.
SUMMARY OF THE INVENTION
[0007] The invention is defined by the claims.
[0008] According to examples in accordance with an aspect of the invention, there is provided
a wearable air purification device for delivering purified air for a wearer of the
wearable air purification device to breathe, the wearable air purification device
comprising: an air treatment unit for treating ambient air in order to generate said
purified air; a first flow path along which the purified air for the wearer to breathe
is displaceable towards the wearer; at least one second flow path along which ambient
air is displaceable; an air displacement assembly for generating airflow along the
first flow path and along the at least one second flow path; a Peltier element comprising
a first side and a second side, the Peltier element being configured to provide cooling
at one of the first and second sides when providing heating at the other of the first
and second sides, wherein the first side and the first flow path are arranged to enable
heat exchange between the first side and air being displaced along the first flow
path, and the second side and the at least one second flow path are arranged to enable
heat exchange between the second side and the ambient air being displaced along the
at least one second flow path.
[0009] By the first side of the Peltier element and the first flow path being arranged to
enable heat exchange between the first side and air being displaced along the first
flow path, the wearer may ultimately be provided with air that has been subjected
to purifying treatment by the air treatment unit and temperature control via the first
side of the Peltier element.
[0010] Moreover, using ambient air, in other words air that has not been treated by any
air treatment unit of the wearable air purification device, for heat exchange at the
second side of the Peltier element may provide various benefits. In particular, resistance
for the first flow path can be reduced due to less outlet resistance. Moreover, avoiding
treatment of air being used for heat exchange at the second side of the Peltier element
may mean that air treatment unit replacement and/or servicing is less frequently required,
with concomitant benefit in terms of prolonging operating lifetime of the wearable
air purification device.
[0011] Alternatively or additionally, generating airflow along the second flow path(s) for
heat exchange with the second side of the Peltier element may be more efficient without
an air treatment unit being included for treating this ambient airflow. This is due
to flow resistance in the second flow path(s) associated with such an air treatment
unit being avoided. Such efficient operation may be particularly desirable in the
context of the wearable air purification device because of the importance of prolonging
device operation, e.g. by preserving battery life.
[0012] In at least some embodiments, the air displacement assembly comprises a first air
displacement device for displacing air along the first flow path, and a second air
displacement device for displacing the ambient air along the at least one second flow
path.
[0013] Employing two such air displacement devices that are distinct from each other may
facilitate efficient operation of the wearable air purification device. This may enable
the first air displacement device to be specifically configured for the purpose of
displacing air through the air treatment unit, with the second air displacement device
being specifically configured for the purpose of displacing ambient air in the second
flow path(s) for exchanging heat with the second side of the Peltier element.
[0014] In some embodiments, the air treatment unit is arranged in the first flow path upstream
of the first side of the Peltier element. This may provide a relatively efficient
and effective way of providing the purified and temperature-controlled air to the
wearer, since the heating or cooling of the air does not have to be implemented in
a way that accounts for influence of the air treatment unit on the temperature of
the air being ultimately supplied to the wearer.
[0015] Alternatively, the air treatment unit may be arranged in the first flow path downstream
of the first side of the Peltier element.
[0016] Such an arrangement of the air treatment unit relative to the Peltier element may
be beneficial in terms of treatment of the air by the air treatment unit. For example,
treatment of pollutants by the air treatment unit may be more effective when the air
has been first heated or cooled by the Peltier element upstream of the air treatment
unit.
[0017] In some embodiments, cooling is provided at the first side of the Peltier element.
Thus, cooled purified air may be provided to the wearer. This may assist to enhance
comfort of the wearer when exposed to warm ambient conditions, e.g. warm weather conditions.
[0018] Alternatively or additionally, heating is provided at the first side of the Peltier
element. Thus, warm purified air may be provided to the wearer. This may assist to
enhance comfort of the wearer when exposed to cold ambient conditions, e.g. cold weather
conditions.
[0019] In some embodiments, the Peltier element is controllable to enable switching between
a first mode in which the Peltier element provides cooling at the first side, and
a second mode in which the Peltier element provides heating at the first side. Thus,
the temperature of the purified air provided to the wearer may be adjustable, for
instance according to the ambient conditions, e.g. weather conditions, to which the
wearer is being exposed.
[0020] In some embodiments, the wearable air purification device comprises a user interface
configured to enable a user to select airflow provided by the air displacement assembly.
Alternatively or additionally, the wearable air purification device comprises a user
interface configured to enable a user to select the first mode or the second mode.
[0021] The user interface can take any suitable form. In some embodiments, the user interface
comprises a control button for enabling the user to select (at least) the first mode
or the second mode.
[0022] In some embodiments, the air treatment unit comprises one or more air filters that
treat the ambient air at least partly by filtration of the ambient air. For example,
the filter(s) may be configured to remove outdoor particles, pollen, bacteria particles,
virus particles, and/or harmful gases.
[0023] The one or more filters may comprise at least one pleated air filter.
[0024] In some embodiments, the air treatment unit comprises a high efficiency particulate
air (HEPA) filter and/or an activated carbon filter.
[0025] Such a HEPA filter and/or activated carbon filter may treat, e.g. remove, outdoor
particles, pollen, bacteria particles, virus particles, and/or harmful gases.
[0026] In some embodiments, the wearable air purification device comprises a surface for
contacting the wearer, which surface is in thermal contact with the first side of
the Peltier element. This may assist the wearer to perceive, via skin contact, the
Peltier elementprovided temperature control over the purified air being supplied to
them.
[0027] In some embodiments, the wearable air purification device comprises a face-covering
member arranged to oppose at least part of the wearer's face but with a gap being
provided between the face-covering member and the at least part of the wearer's face.
The purified air displaced along the first flow path may be permitted to flow in the
gap to reach the wearer's mouth and/or nose.
[0028] The face-covering member may assist to block ambient air, and thus minimize the risk
of ambient air disturbing the flow of purified air into the gap.
[0029] The face-covering member may be located in front of the wearer's face when the wearable
air purification device is being worn, with the clean airflow being guided in the
area between the wearer's nose and the face-covering member.
[0030] Inclusion of the face-covering member in the wearable air purification device may
assist to enhance the wearer's comfort for several reasons. First, wearing comfort
may be enhanced because the purified airflow in combination with the gap may provide
protection that avoids the wearer needing to wear a tight mask on their face, which
can otherwise cause red marks on the wearer's skin. Moreover, breathing comfort may
be enhanced due to a positive pressure of purified air in the gap. The risk of high
CO
2 levels in the space/gap in which air is breathed into the wearer's nose and/or mouth
can also be lessened due to the flow of purified air.
[0031] The Peltier element may further assist to control temperature and humidity, e.g.
relative humidity, of the purified air supplied into the gap. This may provide enhanced
comfort to the wearer, noting that the temperature-controlled purified air delivered
into the gap may come into contact with the wearer's face, as well as being breathed
by the wearer.
[0032] In some embodiments, the face-covering member comprises an optically transmissive,
e.g. transparent, material for enabling the at least part of the wearer's face to
be viewed therethrough. This may facilitate communication between the wearer and others
able to see the wearer's facial expression through the optically transmissive material.
[0033] In some embodiments, the wearable air purification device is attachable to the wearer's
neck in order to be worn. Such attachment to the wearer's neck may mean that the wearable
air purification device is stably supported when being worn.
[0034] Attachment of the wearable air purification device to the wearer's neck can be implemented
in any suitable manner, such as by a wearable structure main body of the wearable
air purification device extending at least partially around and fitting against the
wearer's neck.
[0035] A center of gravity of the wearable air purification device may be located where
the wearable structure main body contacts the wearer's neck, in other words at a neck
touching region of the wearable structure main body.
[0036] In some embodiments, the wearable air purification device comprises a battery holder
for holding one or more batteries for powering the wearable air purification device,
with the battery compartment being arranged to expose the one or more batteries being
held by the battery holder to airflow provided by the air displacement assembly. This
may assist with thermal management, e.g. cooling, of the one or more batteries.
[0037] In some embodiments, a first side heat sink is provided at the first side of the
Peltier element to exchange heat with the air being displaced along the first flow
path. A first heat exchange flow path may, for example, be defined through the first
side heat sink in such a way that the air, e.g. purified air, being displaced along
the first heat exchange flow path makes contact with the first side heat sink.
[0038] In some embodiments, a component provided at the first side of the Peltier element
may be connected to, e.g. in thermal contact with, the neck touching region of the
wearable structure main body.
[0039] For example, the neck touching region may be connected to, e.g. in thermal contact
with, the first side heat sink.
[0040] Thus, the neck touching region may assist the wearer to perceive that control is
being exerted over the temperature of the purified air being delivered to them.
[0041] In some embodiments, a second side heat sink is provided at the second side of the
Peltier element to exchange heat with the ambient air being displaced along the at
least one second flow path. A second heat exchange flow path may, for example, be
defined through the second side heat sink in such a way that the ambient air being
displaced along the second heat exchange flow path makes contact with the second side
heat sink.
[0042] These and other aspects of the invention will be apparent from and elucidated with
reference to the embodiment(s) described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] For a better understanding of the invention, and to show more clearly how it may
be carried into effect, reference will now be made, by way of example only, to the
accompanying drawings, in which:
FIG. 1 shows a wearable air purification device according to an example; and
FIG. 2 shows part of a wearable air purification device according to an example.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0044] The invention will be described with reference to the Figures.
[0045] It should be understood that the detailed description and specific examples, while
indicating exemplary embodiments of the apparatus, systems and methods, are intended
for purposes of illustration only and are not intended to limit the scope of the invention.
These and other features, aspects, and advantages of the apparatus, systems and methods
of the present invention will become better understood from the following description,
appended claims, and accompanying drawings. It should be understood that the Figures
are merely schematic and are not drawn to scale. It should also be understood that
the same reference numerals are used throughout the Figures to indicate the same or
similar parts.
[0046] Provided is a wearable air purification device for delivering purified air for a
wearer of the wearable air purification device to breathe. The wearable air purification
device comprises an air treatment unit for treating ambient air in order to generate
said purified air. Purified air for the wearer to breathe is displaceable towards
the wearer along a first flow path. Ambient air, in other words air that has not been
treated by an air treatment unit of the wearable air purification device, is displaceable
along at least one second flow path. A Peltier element comprises a first side and
a second side. The Peltier element is configured to provide cooling at one of the
first and second sides when providing heating at the other of the first and second
sides. The first side and the first flow path are arranged to enable heat exchange
between the first side and air being displaced along the first flow path. The second
side and the at least one second flow path are arranged to enable heat exchange between
the second side and the ambient air being displaced along the at least one second
flow path.
[0047] FIG. 1 schematically depicts a wearable air purification device 100 according to
an example. The wearable air purification device 100 is configured to enable the wearable
air purification device 100 to be worn by a wearer 102, e.g. a human wearer 102.
[0048] In some embodiments, such as shown in FIG. 1, the wearable air purification device
100 is attachable to the wearer's 102 neck in order to be worn. Such attachment to
the wearer's 102 neck may mean that the wearable air purification device 100 is stably
supported when being worn.
[0049] Attachment of the wearable air purification device 100 to the wearer's neck can be
implemented in any suitable manner, such as by a wearable structure main body 103
of the wearable air purification device 100 extending at least partially around and
fitting against the wearer's 102 neck.
[0050] A center of gravity of the wearable air purification device 100 may be located where
the wearable structure main body 103 contacts the wearer's 102 neck, in other words
at a neck touching region 105 of the wearable structure main body 103.
[0051] This may assist to ensure that wearable air purification device 100 is stable when
being worn.
[0052] The wearable air purification device 100 comprises an air treatment unit 104 for
treating ambient air. Treatment of the ambient air by the air treatment unit 104 generates
purified air. This treatment may involve treatment of pollutants in the ambient air.
[0053] It is noted at this point that the term "ambient air" can be regarded as referring
to air of the surrounding area or vicinity in which the wearable air purification
device 100 is being used.
[0054] Treatment of pollutants, e.g. gaseous and/or particulate pollutants, in the ambient
air by the air treatment unit 104 may comprise removal, conversion and/or inactivation
of the pollutants in the ambient air.
[0055] Conversion of pollutants may involve reacting the pollutants to convert them into
species that are not harmful, or at least less harmful than the pollutants.
[0056] Removal of pollutants may involve absorption or adsorption of the pollutants to remove
the pollutants from, or at least lower the concentration of the pollutants in, the
purified air relative to the ambient air.
[0057] The term "inactivation" refers to infectivity prevention of pathogenic pollutants,
such as virus particles/aerosols.
[0058] In some embodiments, the air treatment unit 104 comprises one or more air filters
that treat the ambient air at least partly by filtration of the ambient air. For example,
the filter(s) may be configured to remove outdoor particles, pollen, bacteria particles,
virus particles, and/or harmful gases.
[0059] The, e.g. each of the, one or more filters may have a surface area in the range 0.01
to 0.10 m
2, for example 0.05 m
2 +-20%.
[0060] Alternatively or additionally, the e.g. each of the, one or more filters may exhibit
a pressure drop of 20 to 40 Pa, for example 29 Pa +-20%. The pressure drop could be
measured using a typical pressure measurement device like TSI 8130 at the given airflow
rate.
[0061] The one or more filters may comprise at least one pleated air filter.
[0062] In some embodiments, the air treatment unit 104 comprises a high efficiency particulate
air (HEPA) filter and/or an activated carbon filter.
[0063] Such a HEPA filter and/or activated carbon filter may treat, e.g. remove, outdoor
particles, pollen, bacteria particles, virus particles, and/or harmful gases.
[0064] A first flow path 106 is defined in the wearable air purification device 100 along
which the purified air is displaceable towards the wearer 102, in particular towards
the wearer's 102 nose and/or mouth. The purified air is thus deliverable via the first
flow path 106 towards the wearer 102 for the wearer 102 to breathe. The wearer's 102
breathing of the purified air is denoted in FIG. 1 by the double-headed arrow 107.
[0065] Implicit is the inclusion of one or more air inlets for admitting ambient air that
is then treated by the air treatment unit 104 to generate purified air that is delivered
via the first flow path 106 to the wearer 102. Such admission of ambient air, in other
words inlet flow, is denoted in FIG. 1 by the arrows 109.
[0066] It is noted, with reference to FIG. 2, that ambient air, in other words ambient air
that has not been treated by any air treatment unit included in the wearable air purification
device 100 to generate purified air, is displaceable along at least one second flow
path 108A, 108B defined in the wearable air purification device 100.
[0067] The second flow path(s) 108A, 108B can each be regarded as being separate from the
first flow path 106.
[0068] The function of the second flow path(s) 108A, 108B is different from the purified
air delivery function of the first flow path 106. This different function of the second
flow path(s) 108A, 108B is explained in more detail herein below.
[0069] The wearable air purification device 100 comprises an air displacement assembly 110,
112 for generating airflow along the first flow path 106 and along the second flow
path(s) 108A, 108B.
[0070] Thus, air is displaceable along the first flow path 106 and the ambient air is displaceable
along the second flow path(s) 108A, 108B by operation of the air displacement assembly
110, 112.
[0071] Referring to FIGs. 1 and 2, the wearable air purification device 100 comprises a
Peltier element 114 that includes a first side 116, e.g. an internal side. In at least
some embodiments, the first side 116 comprises a first side heat sink 117. The Peltier
element 114 further comprises a second side 118, e.g. an external side. In at least
some embodiments, a second side heat sink 119 is provided at the second side 118.
The Peltier element 114 is configured to provide cooling at one of the first and second
sides 116, 118 when providing heating at the other of the first and second sides 118,
116.
[0072] The Peltier element 114 can be regarded as a solid state active heat pump.
[0073] Heat may be transferred from the first side 116 to the second side 118, or from the
second side 118 to the first side 116 depending on a direction of current flow across
a semiconductor junction located between the first and second sides 116, 118 of the
Peltier element 114.
[0074] The structure and function of a Peltier element 114, including suitable semiconductor
materials, namely n-type and p-type semiconductor materials, for achieving the heat
transfer between the two sides 116, 118, is well-known per se and will not be further
described herein for the sake of brevity only.
[0075] With specific reference to FIG. 2, the first side 116 of the Peltier element 114
and the first flow path 106 are arranged to enable heat exchange between the first
side 116 and air being displaced along the first flow path 106. Thus, the wearer 102
is ultimately provided with air that has been subjected to purifying treatment by
the air treatment unit 104 and temperature control via the first side 116 of the Peltier
element 114.
[0076] In some embodiments, such as shown in FIG. 2, the first side heat sink 117 exchanges
heat with the air, e.g. purified air, being displaced along the first flow path 106.
A first heat exchange flow path may, for example, be defined through the first side
heat sink 117 in such a way that the air, e.g. purified air, being displaced along
the first heat exchange flow path makes contact with the first side heat sink 117.
[0077] In some embodiments, such as shown in FIG. 1, the air treatment unit 104 is arranged
in the first flow path 106 upstream of the first side 116 of the Peltier element 114.
This may provide a relatively efficient and effective way of providing the purified
and temperature-controlled air to the wearer 102, since the heating or cooling of
the air does not have to be implemented in a way that accounts for influence of the
air treatment unit 104 on the temperature of the air being ultimately supplied to
the wearer 102.
[0078] Alternatively, the air treatment unit 104 may be arranged in the first flow path
106 downstream of the first side 116 of the Peltier element 114.
[0079] Such an arrangement of the air treatment unit 104 relative to the Peltier element
114 may be beneficial in terms of treatment of the air by the air treatment unit 104.
For example, treatment of pollutants by the air treatment unit 104 may be more effective
when the air has been first heated or cooled by the Peltier element 114 upstream of
the air treatment unit 104. Especially, the clean air passing through the first side
116 of the Peltier element 114 may mean that less or no pollution will contaminate
the first side heat sink 117. Thus, relatively high heat sink conductivity may be
maintained for longer.
[0080] More generally, and referring again to FIG. 2, the second side 118 of the Peltier
element 114 and the at least one second flow path 108A, 108B are arranged to enable
heat exchange between the second side 118 and the ambient air being displaced along
the at least one second flow path 108A, 108B.
[0081] Since this ambient air displaced along the second flow path(s) 108A, 108B is not
being delivered to the wearer 102 for the wearer 102 to breathe, treating it with
an air treatment unit of the type used to generate the purified air is unnecessary.
[0082] Moreover, using untreated ambient air for heat exchange at the second side 118 of
the Peltier element 114 may provide various benefits, such as enhanced efficiency.
Generating airflow along the second flow path(s) 108A, 108B may be more efficient
without an air treatment unit being included for treating the ambient airflow because
flow resistance associated with such an air treatment unit is avoided. Such efficient
operation may be particularly desirable in the context of the wearable air purification
device 100 because of the importance of prolonging device operation, e.g. by preserving
battery life.
[0083] Further, avoiding treatment of air being used for heat exchange at the second side
118 of the Peltier element 114 may mean that air treatment unit replacement and/or
servicing is less frequently required, with concomitant benefit in terms of prolonging
operating lifetime of the wearable air purification device 100.
[0084] The second side heat sink 119 may exchange heat with the ambient air being displaced
along the at least one second flow path 108A, 108B. A second heat exchange flow path
may, for example, be defined through the second side heat sink 119 in such a way that
the ambient air being displaced along the second heat exchange flow path makes contact
with the second side heat sink 119.
[0085] The air displacement assembly 110, 112 can be configured in any suitable manner provided
that the air displacement assembly 110, 112 is capable of providing the airflow, and
thus displacement of air, along the first flow path 106 and along the second flow
path(s) 108A, 108B.
[0086] In at least some embodiments, such as shown in FIGs. 1 and 2, the air displacement
assembly 110, 112 comprises a first air displacement device 110 for displacing air
along the first flow path 106, and a second air displacement device 112 for displacing
the ambient air along the, e.g. each of the, at least one second flow path 108A, 108B.
[0087] Employing two such air displacement devices 110, 112 that are distinct from each
other, may facilitate efficient operation of the wearable air purification device
100. This may enable the first air displacement device 110 to be specifically configured
for the purpose of displacing air through the air treatment unit 104, with the second
air displacement device 112 being specifically configured for the purpose of displacing
ambient air in the second flow path(s) 108A, 108B for exchanging heat with the second
side 118 of the Peltier element 114.
[0088] The first air displacement device 110 may comprise, e.g. be defined by, a first motorized
fan.
[0089] Any suitable motor can be contemplated for rotating the first motorized fan. In some
embodiments, the motor comprises, e.g. is defined by, a coreless motor.
[0090] Such a coreless motor may have sufficiently high torque to effectively overcome the
flow resistance provided by the air treatment unit 104, e.g. to overcome filter pressure.
[0091] In some embodiments, the first air displacement device 110 comprises, e.g. is defined
by, a centrifugal fan.
[0092] Such a centrifugal fan may assist to overcome the flow resistance/pressure drop provided
by the air treatment unit 104, e.g. pleated filter-comprising air treatment unit 104.
[0093] A working point minimum requirement for the first air displacement device 110, e.g.
centrifugal fan, may be about 12.5 m
3/h, 38 Pa. The term "about" in this context is intended to mean a tolerance of +-20%.
[0094] It is noted that higher flows may be required, for example when the wearer's 102
breathing demands are more extreme, such as when the wearer 102 is running. In such
scenarios, the fan working point may be four to five times higher than the above-mentioned
working point minimum requirement.
[0095] The first air displacement device 110, e.g. centrifugal fan, can be arranged in the
wearable air purification device 100 in any suitable manner. In some embodiments,
such as shown in FIG. 1, the first air displacement device 110 is arranged in the
first flow path 106 between the air treatment unit 104 and the first side 116 of the
Peltier element 114.
[0096] Thus, the ambient air is first drawn into the air treatment unit 104 by the first
air displacement device 110, e.g. centrifugal fan, downstream of the air treatment
unit 104.
[0097] Alternatively or additionally, the first air displacement device 110, e.g. centrifugal
fan, may be arranged/located at the back of the wearer's 102 neck when the wearable
air purification device 100 is being worn.
[0098] The first air displacement device 110 may be a relatively bulky component of the
wearable air purification device 100. However, positioning the first air displacement
device 110 at the back of the wearer's 102 neck may mitigate the risk that the wearable
air purification device 100, and the first air displacement device 110 in particular,
hampers movement/activities of the wearer 102.
[0099] The second air displacement device 112 may comprise, e.g. be defined by, a second
motorized fan.
[0100] In some embodiments, such as shown in FIG. 2, the second air displacement device
112, e.g. second motorized fan, is arranged adjacent, e.g. beneath, the second side
118 of the Peltier element 114.
[0101] Such an arrangement may facilitate heat transfer between the ambient air being displaced
along the second flow path(s) 108A, 108B and the second side 118 of the Peltier element
114.
[0102] In some embodiments, such as shown in FIG. 2, the second air displacement device
112, e.g. second motorized fan, may be arranged adjacent, e.g. beneath, the second
side heat sink 119.
[0103] The second flow path(s) 108A, 108B can be implemented in any suitable manner. In
some embodiments, such as shown in FIG. 2, a second flow path 108A is defined between
an ambient air inlet 120A, across at least part of the second side 118 of the Peltier
element 114, e.g. through the second side heat sink 119, and to an air outlet 120B.
[0104] In addition to the second flow path 108A, one or more further second flow paths 108B
may be defined between respective further ambient air inlet(s) 120C, across at least
part of the second side 118 of the Peltier element 114, e.g. through the second side
heat sink 119, and to the air outlet 120B.
[0105] The second air displacement device 112, e.g. second motorized fan, may be arranged
to draw ambient air through the ambient air inlet(s) 120A, 120C, across at least part
of the second side 118 of the Peltier element 114, e.g. through the second side heat
sink 119, and expel the cooled or heated ambient air via the air outlet 120B.
[0106] In some embodiments, such as shown in FIG. 2, a Peltier airflow structure comprising
the Peltier element 114, the second air displacement device 112, and the second flow
path(s) 108A, 108B, is arranged to be symmetrically located around the wearer's 102
neck when the wearable air purification device 100 is being worn.
[0107] This may assist stable supporting of the wearable air purification device 100 while
the wearable air purification device 100 is being worn.
[0108] In some embodiments, cooling is provided at the first side 116 of the Peltier element
114. Thus, cooled purified air may be provided to the wearer 102. This may assist
to enhance comfort of the wearer 102 when exposed to warm ambient conditions, e.g.
warm weather conditions.
[0109] In such embodiments, the correspondingly heated second side 118 of the Peltier element
114 may transfer heat to the ambient air displaced along the second flow path(s) 108A,
108B.
[0110] In some embodiments, heating is provided at the first side 116 of the Peltier element
114. Thus, warm purified air may be provided to the wearer 102. This may assist to
enhance comfort of the wearer 102 when exposed to cold ambient conditions, e.g. cold
weather conditions.
[0111] In such embodiments, the correspondingly cooler second side 118 of the Peltier element
114 may receive heat from the ambient air displaced along the second flow path(s)
108A, 108B.
[0112] In some embodiments, the Peltier element 114 is controllable to enable switching
between a first mode in which the Peltier element 114 provides cooling at the first
side 116, and a second mode in which the Peltier element 114 provides heating at the
first side 116.
[0113] Thus, the temperature of the purified air provided to the wearer 102 may be adjustable,
for instance according to the ambient conditions, e.g. weather conditions, to which
the wearer 102 is being exposed.
[0114] The Peltier element 114 may switch between the first mode and the second mode by
changing the direction of current flow across a semiconductor junction located between
the first and second sides 116, 118 of the Peltier element 114.
[0115] The control over the Peltier element 114 that enables switching between the first
and second modes can be implemented in any suitable manner. In some embodiments, the
wearable air purification device 100 comprises a user interface (not visible) configured
to enable a user to select the first mode or the second mode.
[0116] The user interface can take any suitable form. In some embodiments, the user interface
comprises a control button for enabling the user to select the first mode or the second
mode.
[0117] The user interface, e.g. control button, may be regarded as enabling the user, e.g.
the wearer 102, to enter an indication of whether the Peltier element 114 is to be
controlled to adopt the first mode or the second mode.
[0118] The wearable air purification device 100 may comprise a control system configured
to control the Peltier element, e.g. via the direction of current flow across the
Peltier element's 114 semiconductor junction, to adopt the first mode or the second
mode based on the user-entered indication.
[0119] As an alternative or in addition to enabling switching between the first and second
modes, the user interface, e.g. control button, may be configured to select activation
or deactivation of the Peltier element 114.
[0120] Thus, the user, e.g. the wearer 102, can choose whether or not to use the temperature
control functionality of the wearable air purification device 100, for instance according
to remaining battery life, ambient temperature conditions, and/or pollutant(s) level
in the ambient air.
[0121] In some embodiments, the Peltier element 114 is controllable to enable switching
between the first mode or the second mode and/or between activation or deactivation
of the Peltier element 114 based on data, e.g. sensory data from a sensor, indicative
of temperature of the ambient air.
[0122] For example, should the data be indicative of the temperature of ambient air reaching
or exceeding an upper threshold, the control system may control the Peltier element
114 to adopt the first mode, and/or should data be indicative of the temperature of
ambient air reaching or falling below a lower threshold, the control system may control
the Peltier element 114 to adopt the second mode.
[0123] Alternatively or additionally, the Peltier element 114 may be activated or deactivated
based on the data indicative of temperature of the ambient air.
[0124] The user, e.g. the wearer 102, may thus be enabled to, for instance, select from
a "normal purification mode" (without temperature control over the purified air delivered
to the wearer 102), a purification and cooling mode (in other words the first mode),
and a purification and heating mode (in other words the second mode).
[0125] In some embodiments, the user interface is configured to enable the user to select
airflow provided by the air displacement assembly 110, 112, in particular provided
by the first air displacement device 110.
[0126] In embodiments in which the first air displacement device 110 comprises a motorized
fan, e.g. centrifugal fan, the user interface may enable the user to select different
fan speeds.
[0127] In some embodiments, a control button, for example an additional control button that
is provided in addition to the control button that enables control over the Peltier
element 114, enables the user to select the airflow provided by the air displacement
assembly 110, 112, for example provided by the first air displacement device 110.
[0128] In a non-limiting example, at least two control buttons are included in the wearable
air purification device 100: a control button for selecting fan speed, and an additional
control button for selecting the first or second mode (and/or activation or deactivation)
of the Peltier element 114.
[0129] In some embodiments, and referring to FIGs. 1 and 2, a component provided at the
first side 116 of the Peltier element 114 may be connected to the neck touching region
105 of the wearable structure main body 103. For example, the neck touching region
105 may be connected to the first side heat sink 117.
[0130] Thus, the neck touching region 105 may assist the wearer 102 to perceive that control
is being exerted over the temperature of the purified air being delivered to them.
The wearer 102 may, for example, be assisted to perceive a difference in temperature
of the first side 116 of the Peltier element 114 when the wearable air purification
device 100 is being used in winter compared to summer.
[0131] More generally, the wearable air purification device 100 may include a surface, for
example the neck touching region 105, for contacting the wearer 102, which surface
is in thermal contact with the first side 116 of the Peltier element 114.
[0132] In some embodiments, such as shown in FIG. 1, the wearable air purification device
100 comprises a face-covering member 122 arranged to oppose at least part of the wearer's
102 face but with a gap 123 being provided between the face-covering member 122 and
the at least part of the wearer's 102 face. The purified air displaced along the first
flow path may be permitted to flow in the gap 123 to reach the wearer's 102 mouth
and/or nose.
[0133] The face-covering member 122 may assist to block ambient air, and thus minimize the
risk of ambient air disturbing the flow of purified air into the gap 123.
[0134] As shown in FIG. 1, the face-covering member 122 may be located in front of the wearer's
102 face when the wearable air purification device 100 is being worn, with the clean
airflow being guided in the area between the wearer's 102 nose and the face-covering
member 122.
[0135] The face-covering member 122 can be coupled to the wearable structure main body 103.
This is achievable in in any suitable manner, such as via magnetic coupling and/or
mechanical fixation, e.g. suction coupling, at an interface between the face-covering
member 122 and the wearable structure main body 103.
[0136] More generally, inclusion of the face-covering member 122 in the wearable air purification
device 100 may assist to enhance the wearer's 102 comfort for several reasons. First,
wearing comfort may be enhanced because the purified airflow in combination with the
gap 123 may provide protection that avoids the wearer 102 needing to wear a tight
mask on their face, which can otherwise cause red marks on the wearer's 102 skin.
Moreover, breathing comfort may be enhanced due to a positive pressure of purified
air in the gap 123. The risk of high CO
2 levels in the space/gap 123 in which air is breathed into the wearer's 102 nose and/or
mouth can also be lessened due to the flow of purified air.
[0137] The Peltier element 114 may further assist to control temperature and humidity, e.g.
relative humidity, of the purified air supplied into the gap 123. This may provide
enhanced comfort to the wearer 102, noting that the temperature-controlled purified
air delivered into the gap 123 may come into contact with the wearer's 102 face, as
well as being breathed by the wearer 102.
[0138] In some embodiments, such as shown in FIG. 2, a purified air outlet 124 may be provided
in the first flow path 106 downstream of the air treatment unit 104 and the first
side 116 of the Peltier element.
[0139] In such embodiments, the purified air outlet 124 may be arranged to supply the purified
air into the gap 123 between the face-covering member 122 and the at least part of
the wearer's 102 face. The latter is denoted in FIG. 1 by the arrows 125.
[0140] In some embodiments, the face-covering member 122 comprises an optically transmissive,
e.g. transparent, material for enabling the at least part of the wearer's 102 face
to be viewed therethrough. This may facilitate communication between the wearer 102
and others able to see the wearer's 102 facial expression through the optically transmissive
material.
[0141] It is noted at this point that the wearable air purification device 100, and in particular
the air displacement assembly 110, 112 and the Peltier element 114 included in the
wearable air purification device 100, is powerable in any suitable manner, such as
via one or more batteries 126.
[0142] The one or more batteries 126 may also power the wearable air purification device's
100 control system, e.g. control board.
[0143] The one or more batteries 126 may, for example, be arranged to balance the center
of gravity of the wearable air purification device 100. To this end, the one or more
batteries 126 may be located in front or at the back of the wearer's 102 neck when
the wearable air purification device 100 is being worn, and/or at a side between the
front and back of the wearer's 102 neck.
[0144] In some embodiments, the wearable air purification device 100 comprises a battery
holder for holding the one or more batteries 126 that power the wearable air purification
device 100.
[0145] In such embodiments, the battery compartment may be arranged to expose the one or
more batteries 126 being held by the battery holder to airflow provided by the air
displacement assembly 110, 112. This may assist with thermal management, e.g. cooling,
of the one or more batteries 126.
[0146] Variations to the disclosed embodiments can be understood and effected by those skilled
in the art in practicing the claimed invention, from a study of the drawings, the
disclosure and the appended claims. In the claims, the word "comprising" does not
exclude other elements or steps, and the indefinite article "a" or "an" does not exclude
a plurality.
[0147] The mere fact that certain measures are recited in mutually different dependent claims
does not indicate that a combination of these measures cannot be used to advantage.
[0148] If the term "adapted to" is used in the claims or description, it is noted the term
"adapted to" is intended to be equivalent to the term "configured to". If the term
"arrangement" is used in the claims or description, it is noted the term "arrangement"
is intended to be equivalent to the term "system", and vice versa.
[0149] Any reference signs in the claims should not be construed as limiting the scope.
1. A wearable air purification device (100) for delivering purified air for a wearer
of the wearable air purification device to breathe, the wearable air purification
device comprising:
an air treatment unit (104) for treating ambient air in order to generate said purified
air;
a first flow path (106) along which the purified air for the wearer to breathe is
displaceable towards the wearer;
at least one second flow path (108A, 108B) along which ambient air is displaceable;
an air displacement assembly (110, 112) for generating airflow along the first flow
path and along the at least one second flow path;
a Peltier element (114) comprising a first side (116) and a second side (118), the
Peltier element being configured to provide cooling at one of the first and second
sides (116, 118) when providing heating at the other of the first and second sides
(118, 116),
wherein the first side and the first flow path are arranged to enable heat exchange
between the first side and air being displaced along the first flow path, and the
second side and the at least one second flow path are arranged to enable heat exchange
between the second side and the ambient air being displaced along the at least one
second flow path.
2. The wearable air purification device (100) according to claim 1, wherein the air displacement
assembly (110, 112) comprises a first air displacement device (110) for displacing
air along the first flow path (106), and a second air displacement device (112) for
displacing the ambient air along the at least one second flow path (108A, 108B).
3. The wearable air purification device (100) according to claim 1 or claim 2, wherein
the air treatment unit (104) is arranged in the first flow path (106) upstream of
the first side (116) of the Peltier element (114).
4. The wearable air purification device (100) according to any one of claims 1 to 3,
wherein the Peltier element (114) is configured or configurable to provide cooling
at the first side (116).
5. The wearable air purification device (100) according to any one of claims 1 to 4,
wherein the Peltier element (114) is configured or configurable to provide heating
at the first side (116).
6. The wearable air purification device (100) according to any one of claims 1 to 5,
wherein the Peltier element (114) is controllable to enable switching between a first
mode in which the Peltier element provides cooling at the first side (116), and a
second mode in which the Peltier element provides heating at the first side.
7. The wearable air purification device (100) according to claim 6, comprising a user
interface configured to enable a user to select the first mode or the second mode;
optionally wherein the user interface is further configured to enable the user to
select airflow provided by the air displacement assembly (110, 112).
8. The wearable air purification device (100) according to any one of claims 1 to 7,
wherein the air treatment unit (104) comprises one or more air filters that treat
the ambient air at least partly by filtration of the ambient air.
9. The wearable air purification device (100) according to any one of claims 1 to 8,
comprising a surface for contacting the wearer, which surface is in thermal contact
with the first side (116) of the Peltier element (114).
10. The wearable air purification device (100) according to any one of claims 1 to 9,
comprising a face-covering member (122) arranged to oppose at least part of the wearer's
face but with a gap (123) being provided between the face-covering member and the
at least part of the wearer's face, in which gap said purified air displaced along
the first flow path (106) is permitted to flow to reach the wearer's mouth and/or
nose.
11. The wearable air purification device (100) according to claim 10, wherein the face-covering
member (122) comprises an optically transmissive material for enabling the at least
part of the wearer's face to be viewed therethrough.
12. The wearable air purification device (100) according to any one of claims 1 to 11,
wherein the wearable air purification device is attachable to the wearer's neck in
order to be worn.
13. The wearable air purification device (100) according to any one of claims 1 to 12,
comprising a battery holder for holding one or more batteries (126) for powering the
wearable air purification device, wherein the battery compartment is arranged to expose
the one or more batteries being held by the battery holder to airflow provided by
the air displacement assembly (110, 112).
14. The wearable air purification device (100) according to any one of claims 1 to 13,
wherein a first side heat sink (117) is provided at the first side (118) of the Peltier
element (114) to exchange heat with the air being displaced along the first flow path
(106).
15. The wearable air purification device (100) according to any one of claims 1 to 14,
wherein a second side heat sink (119) is provided at the second side (118) of the
Peltier element (114) to exchange heat with the ambient air being displaced along
the at least one second flow path (108A, 108B).