WO2022117868A1

WO2022117868A1 - Air purification apparatus for a heating, ventilation and cooling system of a vehicle

Info

Publication number: WO2022117868A1
Application number: PCT/EP2021/084264
Authority: WO
Inventors: Vibin AMBUKAN; Mark Allen; Peter Lumsden
Original assignee: Jaguar Land Rover Limited
Priority date: 2020-12-04
Filing date: 2021-12-03
Publication date: 2022-06-09
Also published as: GB2604318B; GB2604318A; GB202019128D0

Abstract

An air purification apparatus (3) comprising: an inlet (32) for airflow; an outlet (34) for purified airflow; a purification channel (36) extending from the inlet to the outlet; and an ultraviolet light source (e.g. UV-C LED 38) configured to emit ultraviolet light into the purification channel to purify the airflow. The apparatus can comprise a reflector (42) configured to reflect the ultraviolet light within the purification channel. The apparatus can comprise an absorber arrangement (44) configured to absorb the ultraviolet light to inhibit leakage of the ultraviolet light through one or both of the inlet and the outlet. The apparatus can be sized to be received in a zonal HVAC duct (24). The apparatus can comprise a temperature regulator (45, 20) configured to control a rate of heat dissipation from the ultraviolet light source.

Description

AIR PURIFICATION APPARATUS FOR A HEATING, VENTILATION AND COOLING SYSTEM OF A VEHICLE

TECHNICAL FIELD

The present disclosure relates to an air purification apparatus. In particular, but not exclusively it relates to an air purification apparatus for a heating, ventilation and cooling (HVAC) system of a vehicle.

BACKGROUND

It is known for a vehicle to comprise an HVAC system. Some vehicle air systems may comprise air purification means.

SUMMARY OF THE INVENTION

It is an aim of the present invention to provide a means for further reducing the number of live pathogens in a vehicle HVAC system.

According to an aspect of the invention there is provided an air purification apparatus comprising: an inlet for airflow; an outlet for purified airflow; a purification channel extending from the inlet to the outlet; an ultraviolet light source configured to emit ultraviolet light into the purification channel to purify the airflow; a reflector configured to reflect the ultraviolet light within the purification channel; and an absorber arrangement configured to absorb the ultraviolet light to inhibit leakage of the ultraviolet light through one or both of the inlet and the outlet.

An advantage is an improved air purification apparatus, because UV-C dosage is increased by the reflector without increasing UV-C aging of UV-C sensitive materials near the inlet/outlet, due to the absorber arrangement.

In some examples, the ultraviolet light source is configured so that the ultraviolet light includes a wavelength from the range 200 nanometres to 280 nanometres, in a UV-C band. In some examples, the ultraviolet light source comprises a light emitting diode configured to emit the ultraviolet light in the UV-C band, and wherein the air purification apparatus comprises a heat exchanger configured to control a temperature of the light emitting diode.

In some examples, the heat exchanger comprises a passive heat exchanger.

In some examples, the passive heat exchanger comprises a heatsink arrangement, and wherein fins of the heatsink arrangement protrude into the purification channel.

In some examples, the heatsink arrangement is configured as at least part of the absorber arrangement.

In some examples, fins of the heatsink arrangement are shaped to block a line of sight to the ultraviolet light source from a cabin of the vehicle.

In some examples, the apparatus comprises an air attachment surface shaped to guide airflow towards the ultraviolet light source.

In some examples, the reflector comprises at least one of: a paint film; a vapour-deposited thin-film; an adhesive film; and a polished surface.

In some examples, the absorber arrangement is configured to exhibit photocatalytic activity upon irradiation by the ultraviolet light source, to perform purification.

In some examples, the absorber arrangement configured to exhibit photocatalytic activity comprises a coating having at least one of: Titanium dioxide; Chromium; Magnesium; Vanadium; and Molybdenum trioxide.

In some examples, the absorber arrangement is at an upstream section and at a downstream section of the purification channel, and wherein the reflector is between the upstream section and the downstream section.

In some examples, the air purification apparatus is sized to receive and purify a first portion of the airflow within a duct of a heating, ventilation and cooling (HVAC) system while enabling a second portion of the airflow in the HVAC duct to bypass the air purification apparatus.

In some examples, the air purification apparatus is sized to be received in a zonal HVAC duct.

In some examples, an activation state of the ultraviolet light source is configured to be dependent on an HVAC zonal activation state. In some examples, the air purification apparatus comprises fixing points for HVAC duct attachment.

In some examples, the air purification apparatus is configured as a removable module, separable from an HVAC duct wall.

According to an aspect of the invention there is provided an air purification apparatus for a heating, ventilation and cooling (HVAC) system of a vehicle, the apparatus comprising: an inlet configured to receive at least part of an airflow of the HVAC system; an outlet configured to return purified airflow to the HVAC system; a purification channel extending from the inlet to the outlet; and an ultraviolet light source configured to emit ultraviolet light into the purification channel to purify the airflow, wherein the air purification apparatus is sized to be received in a zonal HVAC duct.

According to an aspect of the invention there is provided an apparatus for a vehicle, the apparatus comprising: an inlet for airflow; an outlet for purified airflow; a purification channel extending from the inlet to the outlet; an ultraviolet light source configured to emit ultraviolet light into the purification channel to purify the airflow, wherein the ultraviolet light source comprises a light emitting diode configured to emit the ultraviolet light in a UV-C band having a wavelength from the range 200 nanometres to 280 nanometres; and a temperature regulator configured to control a rate of heat dissipation from the light emitting diode.

In some examples, the temperature regulator comprises a heatsink.

In some examples, the apparatus is for a heating, ventilation and cooling (HVAC) system of the vehicle, wherein the inlet is configured to receive at least part of an airflow of the HVAC system, wherein the outlet is configured to return the purified airflow to the HVAC system, and wherein the temperature regulator comprises an electronic thermostat configured to apply a cooling offset to an HVAC temperature setpoint when the light emitting diode is active.

According to an aspect of the invention there is provided a heating, ventilation and cooling (HVAC) system for a vehicle, the HVAC system comprising the air purification apparatus or the apparatus.

According to an aspect of the invention there is provided a vehicle comprising the air purification apparatus or the apparatus or the HVAC system.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination that falls within the scope of the appended claims. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination that falls within the scope of the appended claims, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 illustrates an example of a vehicle;

FIG. 2A schematically illustrates an example of an HVAC system;

FIG. 2B schematically illustrates an example of a controller;

FIG. 3 schematically illustrates an example side view of an air purification apparatus in a duct;

FIG. 4 illustrates an end view of a pair of example air purification modules in a pair of zonal HVAC ducts;

FIG. 5 illustrates a top view of an example air purification module in an HVAC duct;

FIG. 6 illustrates a top perspective of an example air purification module; FIG. 7 illustrates a bottom perspective of an example air purification module;

FIG. 8 illustrates an alternative air attachment surface of an air purification module;

FIG. 9 illustrates an alternative location for ultraviolet light sources;

FIG. 10A illustrates an alternative location of an air purification apparatus, branched off an HVAC duct; and

FIG. 10B illustrates an alternative configuration of an air purification apparatus.

DETAILED DESCRIPTION

FIG. 1 illustrates an example of a vehicle 1 in which embodiments of the invention can be implemented. In some, but not necessarily all examples, the vehicle is a passenger vehicle, also referred to as a passenger car or as an automobile. In other examples, embodiments of the invention can be implemented for other applications, such as commercial vehicles.

FIG. 2A schematically illustrates an example portion of an example HVAC system 2 of the vehicle 1 , configured to distribute air to different zones of the vehicle 1. Other parts of the HVAC system 2 are omitted for simplicity.

In a first embodiment, each zone of the vehicle 1 comprises an individual human-machine interface (HMI) for receiving a temperature selection by an occupant. Therefore, HVAC temperature setpoints for different zones are individually settable. Therefore, the HVAC system 2 can provide air at different temperatures to different zones. Such systems are referred to as multi-zone climate control systems. In a second embodiment, a single HMI controls the temperature for the whole vehicle 1 .

Zones of the vehicle 1 may be separated longitudinally to include a front zone and at least one rear zone for which individual temperatures and/or fan speeds can be set. A front zone comprises a front row of seats including the driver’s seat. A rear zone comprises a rear row of seats. In some vehicles, a rear zone can comprise a rear cargo area.

In some examples, one or more zones of the vehicle 1 may be separated laterally to include a left zone and a right zone for which individual temperatures and/or fan speeds can be set.

FIG. 2A illustrates a plurality of air guiding structures leading to the different zones. The air guiding structures may comprise ducts 24. The ducts 24 are assumed herein to be face ducts leading to face vents that are aimable at headrest/head locations. The same type of arrangement can be used for foot ducts leading to foot vents. A first example of a foot duct is a duct that leads to a footwell. A second example of a foot duct is an underseat duct, that are aimable at footwell locations. Further, windscreen ducts (not shown) could be provided to direct airflow towards a front windscreen of the vehicle 1. An HMI can be provided to select between various combinations of face vents, foot vents and windscreen vents.

The illustrated ducts 24 comprise: a front right duct FR configured to vent to a front right zone; a front left duct FL configured to vent to a front left zone; a rear right duct RR configured to vent to a rear right zone; and a rear left duct RL configured to vent to a rear left zone.

The front right and front left ducts FL, FR could extend laterally behind a dashboard of the vehicle 1 to vents on the dashboard (face ducts) or in the footwell (foot ducts). The rear right and rear left ducts RL, RR could extend longitudinally under a centre console of the vehicle 1 to centre console rear face vents (face ducts) or centre console side face vents (foot ducts).

FIG. 2A also illustrates an electronic thermostat 20. The electronic thermostat 20 is configured to determine an HVAC temperature setpoint based on a user’s selected temperature. The electronic thermostat 20 could be implemented as a controller. FIG. 2B shows an example of a controller 201. The controller 201 comprises: at least one processor 204; and at least one memory device 206 electrically coupled to the processor 204 and having instructions 208 (e.g. a computer program) stored therein, the at least one memory device 206 and the instructions 208 configured to, with the at least one processor 204, provide the functionality of the electronic thermostat 20.

Each zone for which temperature is individually controllable may have its own settable temperature setpoint. A temperature sensor may be located in each zone in the case of a closed-loop system.

In accordance with aspects of the present invention, the HVAC system 2 comprises an air purification apparatus 3, the air purification apparatus 3 comprising a germicidal lamp. A germicidal lamp is an electric light that produces short-wavelength ultraviolet light. The shortwavelength ultraviolet light disrupts genetic structures by destroying the ability of microorganisms to reproduce by causing photo-chemical reactions in nucleic acids (DNA & RNA). This leads to the inactivation of pathogens such as viruses and bacteria and a purified airflow. Therefore, the germicidal lamp of the air purification apparatus 3 comprises at least one ultraviolet light source configured to emit ultraviolet light to purify the airflow. In at least some examples the ultraviolet light source is configured to emit short-wavelength ultraviolet light in the UV-C band. The UV-C band includes wavelengths from the range 100 nanometres to 280 nanometres.

In a specific example, the ultraviolet light source comprises a light emitting diode (UV-C LED). This is because UV-C LEDs have lower power requirements and much smaller sizes than alternative sources such as mercury lamps and excimer lamps. UV-C LEDs can fit into an HVAC system 2 of a vehicle 1 .

In a specific example, the ultraviolet light source is configured to emit UV-C in the 200-280 nanometre wavelength spectrum.

In a specific example, the ultraviolet light source is configured to emit UV-C in the 260-280 nanometre wavelength spectrum. Alternatively, the ultraviolet light source is configured to emit far UV-C in the 207-222 nanometre wavelength spectrum, which has less effect on tissues of other organisms.

It is noted that UV-C can degrade hydrocarbon-based materials including the types of plastics commonly used for automotive HVAC systems, by causing these UV-C sensitive materials to become brittle. Therefore, the present disclosure considers methods of implementing UV-C purification without causing plastic degradation and without having to significantly redesign automotive HVAC systems. Cabin materials such as different plastics, wood and leather can also be UV-C sensitive and the present disclosure minimises UV-C leakage into the cabin.

Dashed boxes in FIG. 2A indicate potential locations for the air purification apparatus 3.

A potential location for the air purification apparatus 3 is within a duct 24, such as a plurality of the ducts 24 shown in FIG. 2A. The duct 24 could be a face duct, a foot duct or a windscreen duct. The air purification apparatus 3 can be a modified duct section or can be an air purification module retrofitted to an existing duct 24. Examples are described herein for reducing the exposure of the UV-C sensitive materials of the duct 24/vehicle to UV-C light, involving the use of absorbers and/or shrouds.

In at least some examples, separate air purification apparatus 3 are provided for a front zone(s) and for a rear zone(s). Optionally, separate air purification apparatus 3 are provided for a left zone and for a right zone. Optionally, separate air purification apparatus 3 are provided for a foot duct and for a face duct of a given zone. Regarding ease of access for servicing and repair, the air purification apparatus 3 at a rear duct (RL, RR) can be located beneath a detachable centre console of the vehicle 1 . Specific examples are illustrated and described herein. The air purification apparatus 3 at a front duct (FL or FR) can be accessible from a glovebox aperture once the glovebox has been removed.

Additionally, or alternatively, a potential location for the air purification apparatus 3 is at an airreceiving end of the HVAC system 2, before the airflow is divided into zones (e.g. evaporator module). For example, outside air and recirculated air could be directed to one or more air purification apparatus 3. Then, the purified airflow is divided into zones and sent to ducts 24. However, at this location a redesign of the HVAC system 2 may be needed because of limited space and difficulty of treating a large volume of air while preventing UV-C leakage.

The specific positioning of the air purification apparatus 3 is influenced by constraints such as: ease of electrical connection of the ultraviolet light source, the best location for airflow, and ease of access for servicing and repair.

FIG. 3 illustrates an example of an air purification apparatus 3 viewed from the side, wherein the apparatus 3 is configured as an air purification module. The air purification apparatus 3 is a self-contained module that could be retrofitted to an existing duct 24.

For example, the air purification apparatus 3 can configured as a push-fit module. Additionally, or alternatively, the air purification apparatus 3 can be configured to be attached to the duct 24, for example via fasteners such as screws.

The air purification apparatus 3 comprises an inlet 32 configured to receive at least part of an airflow of the HVAC system 2, an outlet 34 configured to return purified airflow to the HVAC system 2, a purification channel 36 extending from the inlet 32 to the outlet 34, and the ultraviolet light source 38 which is configured to emit ultraviolet light into the purification channel 36 to purify the airflow.

In the illustration, the air purification apparatus 3 comprises an enclosure 30 having an extruded shape, e.g. prism-shaped. The end faces of the enclosure 30 each comprise an opening, one opening defining the inlet 32 and the other opening defining the outlet 34. The enclosure 30 defines the purification channel 36 and acts as a shroud to prevent UV-C light leakage. Regarding UV-C leakage through the inlet 32 and the outlet 34, other features are described later for reducing end leakage. The enclosure 30 can comprise a material with the ability to withstand and dissipate the heat generated by the ultraviolet light source 38. The material can be resistant to UV-C exposure for the lifetime of the vehicle 1 . The material of the enclosure 30 can comprise a metal such as aluminium, or a non-metal such as a thermally-conductive polymer (e.g. polyamide). The material can be thin-walled.

As illustrated, the air purification apparatus 3 can be sized to receive and purify a first portion P1 of the airflow within the duct 24 while enabling a second portion P2 of the airflow in the duct 24 to bypass the air purification apparatus 3. Advantages include less kinetic energy loss of airflow, a standardised small size likely to fit a variety of duct cross-sections, and smaller inlets/outlets to reduce UV-C light leakage. Therefore, the duct 24 can still be made from UV- C sensitive materials such as existing HVAC plastics.

The small air purification apparatus 3 can have a cross-sectional area of between approximately three 3cm² and approximately 25cm², which is smaller than the cross-section of a typical duct 24. This cross-sectional area can be the area of one or more of: the inlet 32, the outlet 34, or the purification channel 36. The cross-sectional area could be constant if the enclosure 30 is prism-shaped, which is not essential.

Regarding the cross-section shape, the illustrated enclosure 30 comprises one or more substantially flat surfaces onto which substantially flat components such as a substrate for the ultraviolet light source 38 can be readily attached. In an implementation, the illustrated enclosure 30 can have a generally rectangular cross-section shape.

The height and width of the cross-section of the purification channel 36 can be taken between interior edges of the enclosure 30. The height can be a value from the range 1 cm to 6cm such as approximately 1 cm. If the enclosure 30 has an irregular shape, the average height and average width are taken.

The length of the purification channel 36 along which the air flows (perpendicular to crosssection) can be defined as the lengthwise distance from the inlet 32 to the outlet 34, which in the illustration is also the length of the enclosure 30. The length can be a value from the range approximately 5cm to approximately 25cm.

FIG. 3 also illustrates the positioning of the ultraviolet light source 38 within the purification channel 36. The ultraviolet light source 38 is longitudinally positioned in a central longitudinal section of the purification channel 36, i.e. not too close to either the inlet 32 or to the outlet 34. The number of ultraviolet light sources 38 in the air purification apparatus 3 will be dependent on the irradiance level required to achieve the UV-C dosage within the air purification apparatus 3. A single air purification apparatus 3 can comprise a plurality of ultraviolet light sources 38 for its purification channel 36. In this case, two UV-C LEDs 38 are visible, but more could be provided.

Regarding the positioning of a plurality of ultraviolet light sources 38, the ultraviolet light sources 38 are shown located at a common surface of the enclosure 30. This enables multiple ultraviolet light sources 38 to be supported by a common substrate (e.g. printed circuit board, PCB). In other examples, ultraviolet light sources 38 could be distributed around the crosssection which involves more complexity.

In this example, the ultraviolet light sources 38 are located at the surface of the enclosure 30 that demarcates the first portion P1 of air from the second, bypassed portion P2 of air. This is useful because UV-C LEDs 38 tend to emit heat through their backs. Backs of the UV-C LEDs 38 can be exposed to the second, bypassed portion P2 of air, for example through apertures in the enclosure 30, to provide a cooling effect.

Diverging arrows extend from each UV-C LED 38 into the purification channel 36, representing a divergent beam 40 of UV-C light. The ultraviolet light source 38 can be configured to have a beam divergence no more than approximately 140 degrees, such as approximately 120 degrees. In an example, the beam divergence is a value selected from the range approximately 1 10 degrees to approximately 130 degrees. In another example, the beam divergence is narrowed by a lens (not shown) such as a quartz lens. This enables a beam divergence of less than approximately 70 degrees to limit end leakage without needing the enclosure 30 to be particularly long in relation to its height.

The ultraviolet light source 38 can be oriented so that its beam divergence extends upstream as well as downstream. For example, the ultraviolet light source 38 can be oriented approximately perpendicular to the length of the purification channel 36.

In order to provide more UV-C dosage per watt, a reflector 42 can be provided to reflect the ultraviolet light within the purification channel 36, as shown in FIG. 3. The reflector 42 can comprise a reflective surface at the interior face of the enclosure 30. The reflector 42 can comprise an additional reflective layer added to the enclosure 30, or can comprise a reflective surface portion of the existing enclosure material. The reflector 42 can be provided at the central section of the purification channel 36. If the reflector 42 comprises an additional layer, the layer can comprise at least one of a film of reflective paint, a vapour-deposited reflective thin-film; or an adhesive reflective film.

If the reflector 42 comprises a reflective surface portion, the existing enclosure material can be locally polished. Alternatively, the entire interior face of the enclosure material can be reflective and a section of said material can be exposed in the central section of the purification channel 36.

It would be understood that the reflector 42 is configured to be reflective to UV-C, whether or not it is reflective to visual light.

In order to reduce end leakage, the air purification apparatus 3 comprises an absorber arrangement 44 configured to absorb the ultraviolet light to inhibit leakage of the ultraviolet light through one or both of the inlet 32 and the outlet 34. An advantage is the reduction of UV-C exposure to UV-C sensitive duct materials, and also no visible glow through air vents of the cabin.

Any suitable absorber material can be used. The absorber arrangement 44 can comprise an additional layer added to the interior side of the enclosure material, such as a coating, a film, or a painted layer.

In some examples, the absorber arrangement 44 is configured to perform additional purification. The absorber arrangement 44 comprises a material that is further configured to exhibit photocatalytic activity upon irradiation by the ultraviolet light source 38, to perform additional purification.

The absorber arrangement 44 can comprise Titanium, such as Titanium dioxide (TiO2), which in addition to absorbing UV-C, acts as photocatalyst under ultraviolet light to produce free ion radicals (e.g. hydroxyl radicals (OH)). The radicals inactivate pathogens using a photocatalytic Oxidation process. The radicals can remove volatile organic compounds (VOCs), odours and pathogens including bacteria and viruses.

Alternatives to titanium dioxide comprise at least one of: Chromium; Magnesium; Vanadium; Zinc Oxide (ZnO); and Molybdenum.

As illustrated, the absorber arrangement 44 can be provided at upstream and downstream sections to prevent leakage from either end. The absorber arrangement 44 can comprise a first portion at a first, upstream section. The upstream section is downstream of the inlet 32 and upstream of the ultraviolet light source 38. The absorber arrangement 44 can comprise a second portion at a second, downstream section. The downstream section is downstream of the ultraviolet light source 38 and upstream of the outlet 34.

In some examples, the reflector 42 and absorber arrangement 44 are provided at different locations on a single substrate (not shown) such as a film, with the reflector 42 at the central section and the absorber arrangement 44 at the upstream and downstream sections. The substrate may be a separate piece of material that is attached to the enclosure 30.

A controller 201 of an air purification apparatus 3 can be either implemented as part of the electronic thermostat 20 or can be operably coupled to the electronic thermostat 20.

In some examples, the controller 201 can energise the ultraviolet light source 38 in dependence on receiving a signal indicative that airflow is being blown through the duct 24 containing the air purification apparatus 3. The signal could be dependent on user actuation of a fan speed HML The signal could be dependent on user actuation of a vent-opening HML For example, when a user sets a non-zero fan setting and/or opens a vent, the ultraviolet light source 38 is automatically energised without the need for manual intervention.

In some examples, the controller 201 can de-energise the ultraviolet light source 38 in dependence on a signal indicative that airflow is not being blown through the duct 24. For example, when a user deactivates the fan and/or closes a vent, the ultraviolet light source 38 is automatically de-energised without the need for manual intervention. This prevents excessive heat and energy wastage.

If separate air purification apparatus 3 are provided for separate zonal ducts 24, the signal and controller output can be zone-specific. Therefore, starting or stopping airflow in a second zone does not energise or de-energise the ultraviolet light source 38 in a first zone.

In some examples, the controller 201 can energise the ultraviolet light source 38 in dependence on a signal indicating that the vehicle 1 is in a pre-conditioning mode. A preconditioning mode is a mode of the HVAC system 2 that activates the HVAC system 2 to provide a user-preset temperature of the cabin in advance of a programmed time (e.g. departure time).

FIG. 4 illustrates an end view (cross-section view) of a pair of module-type air purification apparatus 3 in a pair of zonal ducts 24 for lateral zones of the vehicle 1 . The air purification apparatus 3 comprises the features shown in FIG. 3. The ducts 24 in this example are left and right face ducts RL, RR for a rear zone(s). As shown in FIG. 4, the ducts 24 can have irregular cross-section shapes and areas. Therefore, the small size of the air purification apparatus 3 enables standardisation for most duct shapes. The air purification apparatus 3 divides the cross-section of the duct 24 into a purification channel 36 and a bypass channel 26.

Although in FIG. 4 the bypass channel 26 has a larger cross-sectional area than the purification channel 36, the air purification apparatus 3 can be located at the portion of the purification channel 36 that receives a high mass flow rate, to capture a large portion of the airflow. The best location can be determined via computational fluid dynamics simulations and/or via physical experiments.

The ultraviolet light source 38 may not be visible from the end view due to features designed to prevent light leakage, some of which are defined later.

As shown in FIG. 4, an aperture 28 in the duct 24 can be sized to receive the air purification apparatus 3 in a plug-socket (push fit) relationship. The size of the aperture 28 can be less than 20cm in length and less than 10cm in width, corresponding to the length and width dimensions of the enclosure. In an example the aperture 28 is approximately 95mm in length and approximately 30mm in width.

The aperture 28 in this example is located at an upper surface of the duct 24, so that the air purification apparatus 3 is accessible from above by removing/opening at least part of a centre console of the vehicle 1. Therefore, the air purification apparatus 3 can be ‘dropped in’ and optionally attached to the duct 24.

As shown in FIG. 4 and also in FIGS. 5-7, the air purification apparatus 3 can comprise a cover 50. The width and length of the cover 50 can be slightly oversized compared to the aperture 28, to provide an interference that prevents the air purification apparatus 3 from falling through the aperture 28.

The cover 50 can be permanently attached to the enclosure 30, or can be a lid removable from the enclosure 30.

The top-down view of FIG. 5 shows that the air purification apparatus 3 can have one or more fixing points 58 such as holes for screws or clips or security fasteners, for attachment to the duct 24 or another supporting structure. In FIG. 5 the fixing points 58 are located on the cover 50. The fixing points 58 may line up with corresponding fixing points (e.g. clips) on the duct 24/supporting structure. The perspective view of FIG. 6 also shows that the cover 50 can have an aperture through which electrical wiring can extend.

FIGS. 5-7 show a top-down view, a front perspective view and a bottom perspective view of the air purification apparatus 3, respectively. The air purification apparatus 3 comprises four UV-C LEDs 38 for illustrative purposes. These Figures also show an example of how temperature can be regulated. UV-C LEDs are only about 2% efficient and produce lots of heat. Therefore, a temperature regulator is provided to control the rate of heat dissipation from the ultraviolet light source 38. A minimum rate of heat dissipation is ensured.

In FIGS. 5-7 the air purification apparatus 3 comprises an optional temperature regulator 45 configured to control a rate of heat dissipation from the ultraviolet light source 38. The temperature regulator comprises a heat exchanger. The heat exchanger can comprise a passive heat exchanger such as a heatsink arrangement 45, as shown.

The heatsink arrangement 45 can comprise a thermally conductive material with a high surface area to volume ratio, such as an arrangement of aluminium or copper fins 46. The fins 46 can be arranged in parallel with small gaps there between. In other embodiments, no fins are provided.

The fins 46 can be thermally coupled to the ultraviolet light source 38 via a base 54 (substrate) of the heatsink arrangement 45. The fins 46 and the base 54 could be a common casting, for example. The base 54 of the heatsink arrangement 45 can be 2-3mm thick, for example. The base 54 can be provided at the central section of the purification channel 36 and configured to receive a substrate 52 of the ultraviolet light source 38. The substrate 52 of the ultraviolet light source 38 may comprise one or more PCBs, for example. The ultraviolet light source 38 is thermally coupled to the base 54 of the heatsink arrangement 45 via any appropriate heat spreader.

In the illustrated embodiment, the heatsink arrangement 45 is located within the purification channel 36 and is therefore exposed to the HVAC airflow.

In this embodiment, the fins 46 extend primarily lengthwise parallel to the airflow, to prevent a blocking/blinding effect.

In this embodiment, no fins 46 are provided in the central section to avoid blocking the ultraviolet light beams 40, and to encourage airflow to pass directly over the ultraviolet light source 38. The fins 46 can terminate far enough from the ultraviolet light source(s) 38 to avoid intersecting the beams 40 and reducing the effective beam divergence.

In this embodiment, the fins 46 of the heatsink arrangement 45 can start outside the central section and extend away from the central section. That is, the fins 46 are at the upstream and/or downstream sections which is where the absorber arrangement 44 is located. In FIG. 5, the upstream fins 46 in the upstream section comprises four side-by-side fins 46. In other embodiments, a different number of side-by-side fins is provided such as three fins 46 or five fins 46. The downstream fins 46 in the downstream section can comprise the same number of fins 46 as the upstream fins 46, or a different number of fins 46.

In this embodiment, the fins 46 can be configured as at least part of the absorber arrangement 44. For example, the fins 46 can be painted/coated in the absorber material.

The fins 46 can be shaped to block a direct line of sight from the inlet 32 and/or outlet 34 to the ultraviolet light source 38. The fins 46 can prevent glow visible from the cabin through air vents. To achieve this, FIGS. 5-7 show that the fins 46 of the heatsink arrangement 45 can be non-linear along their length.

The illustrated fins 46 show an example of the fins 46 changing direction along their lengths (as opposed to along their height from the base 54). The direction change is sufficient that a line of sight to the ultraviolet light source 38 from the outlet 34 and/or inlet 32 of the air purification apparatus 3 is blocked.

In this example, the fins 46 change direction continuously along their length. The fins 46 are continuously curved into sinusoidal shapes (wave-like shapes) with zero or more repetitions. It would be appreciated that the direction change could be provided by any one or more discrete direction changes such as a single hump or v-shape.

In the illustrated example the airflow exiting the fins 46 is directed in the same direction as airflow entering the fins 46. In another example, the fins 46 are configured so that the airflow exits the fins 46 in a different direction such as a diagonal direction. The direction change of the fins 46 blocks the line of sight to the ultraviolet light source 38 from the outlet 34 and/or inlet 32.

Of the above examples, the illustrated shape can result in the least aerodynamic noise.

In another embodiment, the heatsink arrangement 45 is an external heatsink. For example, the fins 46 may be provided outside the purification channel 36. In a further embodiment, a combination of internal and external fins can be provided. In a further embodiment, a smaller heatsink arrangement 45 is integrated into the substrate 52 (e.g. PCB) of the ultraviolet light source 38, as unobtrusively as possible.

A further example of a temperature regulator configured to control the rate of heat dissipation is a software solution. The electronic thermostat 20 may be configured to apply a cooling offset to the HVAC temperature setpoint associated with the duct 24 that the air purification apparatus 3 is connected to. The electronic thermostat 20 may be configured to apply the cooling offset when the ultraviolet light source 38 is active. The magnitude of the cooling offset may be configured in dependence on the heat added to the air by the air purification apparatus 3, so that airflow reaching the vents is at the user’s required temperature.

A further way of improving heat dissipation is to provide an air attachment surface 56 shaped to guide airflow towards the ultraviolet light source 38. Examples are illustrated in FIGS. 6 and 8 and described below.

In FIG. 6, the central section of the purification channel 36 is elevated upwardly relative to the upstream and downstream sections, due to the thicknesses of the base 54 of the heatsink arrangement 45, the PCB 52 and the ultraviolet light source 38. The air attachment surface 56 comprises a ramp leading to the elevation of the central section. A ramp avoids a step and therefore reduces flow separation so that the ultraviolet light source 38 receives some flow. In this example the ramp is part of the base 54 of the heatsink arrangement 45.

FIG. 8 shows an alternative design in which the central section of the purification channel 36 is stepped down relative to the upstream and downstream sections. The air attachment surface 56 comprises a slope sloping down towards the central section in the lengthwise direction, which changes the elevation to avoid any steps. This streamlines the airflow and increases the airflow intersecting the ultraviolet light source 38. The slope could be the surface of the base 54 of the heatsink arrangement 45, for example.

FIGS. 5-7 illustrate other features too, such as an electronic interface 48 configured to receive electrical power and to transmit and/or receive control signals such as power signals, Local Interconnect Network signals, etc. The electronic interface 48 can comprise a physical connector and electrical wiring.

Various alternative designs of the air purification apparatus 3 are described below. Features from the preceding design are carried over unless they are explicitly mentioned as incompatible. FIG. 9 illustrates an alternative design of the air purification apparatus 3, in which the ultraviolet light source 38 and associated components (e.g. PCB 52, heatsink arrangement 45) are mounted facing the opposite direction. They are mounted to the underside of the cover 50 of the air purification apparatus 3.

FIG. 10A schematically illustrates a further alternative design of the air purification apparatus 3. Whereas the preceding version was inserted into a duct 24, the version of FIG. 10A is located outside a duct 24. The air purification apparatus 3 can be plumbed into the duct 24 via an inlet conduit 320 and an outlet conduit 340 (e.g. tubes). The design of FIG. 10A presents less of an obstruction to airflow. The inlet conduit 320 could be connected to the lowest- pressure region of the duct 24 to receive the best airflow, as determined via simulation and/or via experiments.

FIG. 10B schematically illustrates a further alternative design in which the air purification apparatus 3 is a customised duct section, rather than a module. This ensures that the whole of the airflow is purified. The reflector 42 and absorber arrangement 44 may be applied to the interior duct wall. The absorber arrangement 44 may extend far enough lengthwise to go beyond a line of sight of the ultraviolet light source 38, for example, as far as the next kink in the duct 24.

In at least some further embodiments, one or more of the above designs can be implemented as a standalone module located at various locations inside the vehicle, not limited to HVAC system locations. Examples of locations inside the vehicle include: under the driver seat; under passenger seats; in a ceiling area; trunk area; within seats; centre console; post finishers; head rests; or the HVAC system as described above (e.g. evaporators).

For purposes of this disclosure, it is to be understood that the controller(s) described herein can each comprise a control unit or computational device having one or more electronic processors. A vehicle 1 and/or a system thereof may comprise a single control unit or electronic controller or alternatively different functions of the controller(s) may be embodied in, or hosted in, different control units or controllers. A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) to implement the control techniques described herein (including the described method(s)). The set of instructions may be embedded in one or more electronic processors, or alternatively, the set of instructions could be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on one or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present disclosure is not intended to be limited to any particular arrangement. In any event, the set of instructions described above may be embedded in a computer- readable storage medium (e.g., a non-transitory computer-readable storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM and EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application.

As used here ‘module’ refers to a unit or apparatus that excludes certain parts/components that would be added by an end manufacturer or a user.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. An air purification apparatus comprising: an inlet for airflow; an outlet for purified airflow; a purification channel extending from the inlet to the outlet; an ultraviolet light source configured to emit ultraviolet light into the purification channel to purify the airflow; a reflector configured to reflect the ultraviolet light within the purification channel; and an absorber arrangement configured to absorb the ultraviolet light to inhibit leakage of the ultraviolet light through one or both of the inlet and the outlet.

2. The air purification apparatus of claim 1 , wherein the ultraviolet light source is configured so that the ultraviolet light includes a wavelength from the range 200 nanometres to 280 nanometres, in a UV-C band; optionally the ultraviolet light source comprises a light emitting diode configured to emit the ultraviolet light in the UV-C band, and wherein the air purification apparatus comprises a heat exchanger configured to control a temperature of the light emitting diode.

3. The air purification apparatus of claim 2, wherein the heat exchanger comprises a passive heat exchanger; optionally the passive heat exchanger comprises a heatsink arrangement, and wherein fins of the heatsink arrangement protrude into the purification channel.

4. The air purification apparatus of claim 3, wherein the heatsink arrangement is configured as at least part of the absorber arrangement.

5. The air purification apparatus of claim 3 or 4, wherein fins of the heatsink arrangement are shaped to block a line of sight to the ultraviolet light source from a cabin of the vehicle.

6. The air purification apparatus of any preceding claim, comprising an air attachment surface shaped to guide airflow towards the ultraviolet light source.

7. The air purification apparatus of any preceding claim, wherein the reflector comprises at least one of: a paint film; a vapour-deposited thin-film; an adhesive film; and a polished surface.

8. The air purification apparatus of any preceding claim, wherein the absorber arrangement is configured to exhibit photocatalytic activity upon irradiation by the ultraviolet light source, to perform purification; optionally the absorber arrangement configured to exhibit photocatalytic activity comprises a coating having at least one of:

Titanium dioxide;

Chromium;

Magnesium;

Vanadium; and

Molybdenum trioxide.

9. The air purification apparatus of any preceding claim, wherein the absorber arrangement is at an upstream section and at a downstream section of the purification channel, and wherein the reflector is between the upstream section and the downstream section.

10. The air purification apparatus of any preceding claim, wherein the air purification apparatus is sized to receive and purify a first portion of the airflow within a duct of a heating, ventilation and cooling (HVAC) system while enabling a second portion of the airflow in the HVAC duct to bypass the air purification apparatus.

11. The air purification apparatus of any preceding claim, wherein an activation state of the ultraviolet light source is configured to be dependent on an HVAC zonal activation state.

12. The air purification apparatus of any preceding claim, wherein the air purification apparatus is configured as a removable module, separable from an HVAC duct wall.

13. An air purification apparatus for a heating, ventilation and cooling (HVAC) system of a vehicle, the apparatus comprising: an inlet configured to receive at least part of an airflow of the HVAC system; an outlet configured to return purified airflow to the HVAC system; a purification channel extending from the inlet to the outlet; and an ultraviolet light source configured to emit ultraviolet light into the purification channel to purify the airflow, wherein the air purification apparatus is sized to be received in a zonal HVAC duct.

14. An apparatus for a vehicle, the apparatus comprising: an inlet for airflow; an outlet for purified airflow; a purification channel extending from the inlet to the outlet; an ultraviolet light source configured to emit ultraviolet light into the purification channel to purify the airflow, wherein the ultraviolet light source comprises a light emitting diode configured to emit the ultraviolet light in a UV-C band having a wavelength from the range 200 nanometres to 280 nanometres; and a temperature regulator configured to control a rate of heat dissipation from the light emitting diode; optionally the temperature regulator comprises a heatsink.

15. The apparatus of claim 14, for a heating, ventilation and cooling (HVAC) system of the vehicle, wherein the inlet is configured to receive at least part of an airflow of the HVAC system, wherein the outlet is configured to return the purified airflow to the HVAC system, and wherein the temperature regulator comprises an electronic thermostat configured to apply a cooling offset to an HVAC temperature setpoint when the light emitting diode is active.

16. A heating, ventilation and cooling (HVAC) system for a vehicle, the HVAC system comprising the air purification apparatus of any one of claims 1 to 13 or the apparatus of claim 14 or 15.

17. A vehicle comprising the air purification apparatus of any one of claims 1 to 13 or the apparatus of claim 14 or 15 or the HVAC system of claim 16.