EP4445963A1

EP4445963A1 - Wearable air purification device

Info

Publication number: EP4445963A1
Application number: EP23172140.8A
Authority: EP
Inventors: Geng Lai; Wei Su; Xiao Yan ZHU
Original assignee: Versuni Holding BV
Current assignee: Versuni Holding BV
Priority date: 2023-04-10
Filing date: 2023-05-08
Publication date: 2024-10-16

Abstract

Provided is a wearable air purification device (100) for delivering purified air for a wearer (102) of the wearable air purification device to breathe. The wearable air purification device comprises an air treatment unit (104) 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 (106). 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. An air displacement assembly (110, 112) generates airflow along the first flow path and along the at least one second flow path. A Peltier element (114) 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.

Description

FIELD OF THE INVENTION

The invention relates to a wearable air purification device.

BACKGROUND OF THE INVENTION

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.
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.
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.
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.
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

The invention is defined by the claims.
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.
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.
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.
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.
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.
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.
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.
Alternatively, the air treatment unit may be arranged in the first flow path downstream of the first side of the Peltier element.
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.
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.
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.
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.
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.
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.
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.
The one or more filters may comprise at least one pleated air filter.
In some embodiments, the air treatment unit comprises a high efficiency particulate air (HEPA) filter and/or an activated carbon filter.
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.
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.
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.
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.
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.
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 CO₂ 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.
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.
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.
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.
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.
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.
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.
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.
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.
For example, the neck touching region may be connected to, e.g. in thermal contact with, the first side heat sink.
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.
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.
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

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

The invention will be described with reference to the Figures.
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.
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.
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.
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.
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.
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.
This may assist to ensure that wearable air purification device 100 is stable when being worn.
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.
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.
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.
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.
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.
The term "inactivation" refers to infectivity prevention of pathogenic pollutants, such as virus particles/aerosols.
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.
The, e.g. each of the, one or more filters may have a surface area in the range 0.01 to 0.10 m², for example 0.05 m² +-20%.
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.
The one or more filters may comprise at least one pleated air filter.
In some embodiments, the air treatment unit 104 comprises a high efficiency particulate air (HEPA) filter and/or an activated carbon filter.
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.
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.
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.
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.
The second flow path(s) 108A, 108B can each be regarded as being separate from the first flow path 106.
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.
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.
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.
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.
The Peltier element 114 can be regarded as a solid state active heat pump.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
The first air displacement device 110 may comprise, e.g. be defined by, a first motorized fan.
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.
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.
In some embodiments, the first air displacement device 110 comprises, e.g. is defined by, a centrifugal fan.
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.
A working point minimum requirement for the first air displacement device 110, e.g. centrifugal fan, may be about 12.5 m³/h, 38 Pa. The term "about" in this context is intended to mean a tolerance of +-20%.
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.
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.
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.
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.
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.
The second air displacement device 112 may comprise, e.g. be defined by, a second motorized fan.
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.
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.
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.
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.
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.
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.
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.
This may assist stable supporting of the wearable air purification device 100 while the wearable air purification device 100 is being worn.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Alternatively or additionally, the Peltier element 114 may be activated or deactivated based on the data indicative of temperature of the ambient air.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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 CO₂ 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.
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.
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.
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.
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.
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.
The one or more batteries 126 may also power the wearable air purification device's 100 control system, e.g. control board.
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.
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.
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.
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.
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.
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.
Any reference signs in the claims should not be construed as limiting the scope.

Claims

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.
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).
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).
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).
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).
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.
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).
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.
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).
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.
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.
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.
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).
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).
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).