WO2023196155A1

WO2023196155A1 - Air sanitation systems

Info

Publication number: WO2023196155A1
Application number: PCT/US2023/016878
Authority: WO
Inventors: Sivakumar Gopalnarayanan; Ammar Sakarwala
Original assignee: Rheem Manufacturing Company
Priority date: 2022-04-06
Filing date: 2023-03-30
Publication date: 2023-10-12

Abstract

Air sanitation systems are described. The air sanitation device can include an air movement device configured to move air through at least a portion of the air sanitation system, as well as an ultraviolet (UV) cleaning section including a UV light source and a swirling airflow path. The swirling airflow path can twist about the UV light source along at least some of a length of the UV light source.

Description

AIR SANITATION SYSTEMS

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is an International Application of, and claims the benefit of, U.S. Provisional Application No. 63/328,007, filed April 6, 2022, the entirety of which is hereby incorporated by reference.

BACKGROUND

[0002] The COVID-19 pandemic has disrupted countless people’s lives, and efforts to prevent or slow spread of the disease has forced a large number of businesses, schools, and facilities, and events to close or severely reduce the number of people permitted in a single location. Research cited by Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) suggests there is strong evidence that the disease is commonly transmitted via airborne microdroplets emanating from a person’s mouth. These microdroplets can exit a person’s mouth while that person is sneezing, talking, or even simply breathing.

[0003] To help slow or prevent the spread of COVID-19, certain guidelines have been issued to the public. For example, the CDC has provided guidelines to the public, which includes the instruction to wear a mask or face covering. However, some may find a mask to be uncomfortable, cumbersome, or too restrictive to wear for long durations. Another CDC guideline instructs the public to practice social distancing, where a person maintains a distance of at least six feet away from other people not from the person’s household.

[0004] However, various scenarios tested with computational fluid dynamics (CFD) simulations indicate that the six-foot social distancing guideline is insufficient in an indoor environment, especially if the heating, ventilation, and air conditioning (HVAC) system that services the indoor environment has not been outfitted to prevent the routing of microdroplets into the so-called “breathing zone,” which can correspond to the volume within an indoor environment that exists in the range from approximately 4.5 feet (approximately 1.4 meters) from the floor to approximately 7.2 feet (approximately 2.2 meters) from the floor. Such problems can become more pronounced with HVAC systems that have an overhead ventilation configuration in which both the supply vents and the return i vents are located overhead. This can result in circulation of air within the conditioned space, which promote high circulation of microdroplets, which can carry COVID-19. Other HVAC system configurations, such as downflow ventilation systems (e.g., overhead supply vents and floor-level return vents), can provide a decreased amount of circulation within the conditioned space as compared to overhead ventilation systems, but even these HVAC systems can promote an undesirably high amount of air circulation within the conditioned space, which can facilitate movement of microdroplets within the conditioned space. This can increase the chances that a person will inhale or ingest the microdroplets, which can facilitate transmission of COVID-19 or other airborne pathogens. As will be appreciated, the increased air circulation within a conditioned space can undercut the effectiveness of social distancing such that other preventive measures are necessary while indoors.

[0005] To that end, some HVAC systems have been modified to include filters and/or sanitizing devices, such as ultraviolet (UV) light sources, which can help sanitize the air within a conditioned space. HVAC systems including UV light sources are typically configured to expose the air within a duct of the HVAC system to UV radiation. Such preventive measures can sanitize the air that exits from the supply vents into the conditioned space. However, such preventive measures are of no help in ensuring sanitization of air within the space itself (i.e., air that has exited a supply vent but has not yet entered a return vent). Thus, even with existing preventive measures in place, there can still be a high likelihood that microdroplets containing COVID-19 or another pathogen are being circulated within the conditioned space.

[0006] Accordingly, there is a need for devices, systems, or other preventive measures that can help prevent the transmission of microdroplets from person to person, particularly within indoor spaces. It is desirable for such devices, systems, or other preventive measures to require no action on the part of an individual.

SUMMARY

[0007] These and other problems are addressed by the technologies described herein. The disclosed technology relates generally to devices and systems configured to remove and/or divert microdroplets and/or aerosols, which can carry COVID-19 or other pathogens, from the face of some or all of persons located within a room or other space. However, the disclosed technology is not so limited. For example, the disclosed technology includes devices and systems configured to sanitize air flowing within a space.

[0008] The disclosed technology includes an air sanitation system comprising an ultraviolet (UV) cleaning section and an air movement device. The UV cleaning section can include a UV light source and an airflow path rotating about at least a portion of the UV light source such that the airflow path imparts a swirling effect on air passing therethrough. The air movement device can be configured to move air into the air sanitation system via an air inlet, through the UV cleaning section, and out of the air sanitation system via an air outlet.

[0009] The air sanitation system can be housed in a standalone air sanitation device. The air outlet can be located at a height that is greater than or equal to approximately 7 feet with respect to a bottom of the air sanitation device. The air inlet can be located at a height that is between approximately 4.5 feet and approximately 7.2 feet with respect to a bottom of the air sanitation device. The air inlet can be located at a height that is less than approximately 4.5 feet and approximately 7.2 feet with respect to a bottom of the air sanitation device.

[0010] The air sanitation system can be a portion of a heating, ventilation, and air conditioning (HVAC) system.

[0011] The airflow path can form a helix.

[0012] The airflow path can have a first width at a first location along the airflow path and a second width at a second location along the airflow path, and the first width can be greater than the second width.

[0013] The airflow path can have a first width at a first location along the airflow path and a second width at a second location along the airflow path, and the first width can be less than the second width.

[0014] The airflow path can have a first width at a first location along the airflow path, a second width at a second location along the airflow path, and a third width at a third location along the airflow path. The first width can be greater than the second width, and the third width can be greater than the second width. The first and third widths can be approximately equal. Alternatively, the first width can be different from the third width. [0015] The airflow path can have an inner edge, and at least a portion of the inner edge can abut the UV light source. The airflow path can have an inner edge, and at least a portion of the inner edge can be spaced apart from the UV light source.

[0016] The airflow path can have an outer edge, and at least a portion of the outer edge can abut the UV light source. The airflow path can have an inner edge, and at least a portion of the inner edge can be spaced apart from the UV light source.

[0017] The airflow path can be one of a plurality of airflow paths included in the UV cleaning section, and at least one of the plurality of airflow paths can be separated from an adjacent airflow path by a gap.

[0018] The airflow path can have a pitch angle relative a horizontal plane intersecting the lowest portion of a given location of the airflow path. The pitch angle can be between approximately 15° and approximately 75°. The pitch angle can be constant along a length of the airflow path. Alternatively, the pitch angle can vary along the length of the airflow path.

[0019] Further features and elements of the disclosed technology, and the advantages offered thereby, are explained in greater detail hereinafter with reference to specific examples illustrated in the accompanying drawings, wherein like elements are indicated be like reference designators.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, are incorporated into, and constitute a portion of, this disclosure, illustrate various implementations and aspects of the disclosed technology and, together with the description, serve to explain the principles of the disclosed technology. In the drawings:

[0021] FIGs. 1A-1D illustrate example air sanitation systems, in accordance with the disclosed technology;

[0022] FIGs. 2A and 2B illustrate example air sanitation airflow pathways, in accordance with the disclosed technology;

[0023] FIGs. 3A and 3B illustrate example air sanitation airflow pathways, in accordance with the disclosed technology; [0024] FTGs. 4A and 4B illustrate example air sanitation airflow pathways, in accordance with the disclosed technology;

[0025] FIGs. 5A and 5B illustrate example air sanitation airflow pathways, in accordance with the disclosed technology;

[0026] FIG. 6 illustrates an example air sanitation airflow pathway, in accordance with the disclosed technology;

[0027] FIG. 7 illustrates an example air sanitation pathway configuration having multiple flow paths, in accordance with the disclosed technology; and

[0028] FIG. 8 illustrates an example air sanitation system including an air sanitation pathway, in accordance with the disclosed technology.

DETAILED DESCRIPTION

[0029] Throughout this disclosure, systems and methods are described with respect to air sanitation devices, and air sanitation systems, that can be positioned within a room and are configured to clean, filter, and/or sterilize the air within the breathing zone of an indoor environment. In particular, the disclosed technology can be useful in indoor environments serviced by a HVAC system, although one having skill in the art will recognize that the disclosed technology can be applicable to multiple scenarios and applications.

[0030] Some implementations of the disclosed technology will be described more fully with reference to the accompanying drawings. This disclosed technology may, however, be embodied in many different forms and should not be construed as limited to the implementations set forth herein. The components described hereinafter as making up various elements of the disclosed technology are intended to be illustrative and not restrictive. Indeed, it is to be understood that other examples are contemplated. Many suitable components that would perform the same or similar functions as components described herein are intended to be embraced within the scope of the disclosed electronic devices and methods. Such other components not described herein may include, but are not limited to, for example, components developed after development of the disclosed technology.

[0031] Throughout this disclosure, various aspects of the disclosed technology can be presented in a range format (e.g., a range of values). It should be understood that such descriptions are merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the disclosed technology. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual rational numerical values within that range. For example, a range described as being “from 1 to 6” includes the values 1, 6, and all values therebetween. Likewise, a range described as being “between 1 and 6” includes the values 1, 6, and all values therebetween. The same premise applies to any other language describing a range of values. That is to say, the ranges disclosed herein are inclusive of the respective endpoints, unless otherwise indicated.

[0032] Herein, the use of terms such as “having,” “has,” “including,” or “includes” are open-ended and are intended to have the same meaning as terms such as “comprising” or “comprises” and not preclude the presence of other structure, material, or acts. Similarly, though the use of terms such as “can” or “may” are intended to be open-ended and to reflect that structure, material, or acts are not necessary, the failure to use such terms is not intended to reflect that structure, material, or acts are essential. To the extent that structure, material, or acts are presently considered to be essential, they are identified as such.

[0033] It is to be understood that the mention of one or more method steps does not preclude the presence of additional method steps or intervening method steps between those steps expressly identified. Similarly, it is also to be understood that the mention of one or more components in a device or system does not preclude the presence of additional components or intervening components between those components expressly identified.

[0034] Although the disclosed technology may be described herein with respect to various systems and methods, it is contemplated that embodiments or implementations of the disclosed technology with identical or substantially similar features may alternatively be implemented as methods or systems. For example, any aspects, elements, features, or the like described herein with respect to a method can be equally attributable to a system. As another example, any aspects, elements, features, or the like described herein with respect to a system can be equally attributable to a method.

[0035] Reference will now be made in detail to example embodiments of the disclosed technology, examples of which are illustrated in the accompanying drawings and disclosed herein. Wherever convenient, the same reference numbers will be used throughout the drawings to refer to the same or like parts. [0036] As explained above, certain HVAC systems are designed to filter and/or sanitize air passing therethrough such that filtered and/or sanitized air can be provided to a conditioned space. However, this does not address pathogens introduced directly into the air within the conditioned space itself. Moreover, existing systems typically attempt to clean, filter, and/or sterilize all of the air within a space (e.g., a room, a conditioned space), which is typically not practicable due at least to the introduction of pathogens by persons located within the space. Moreover, many airborne pathogens, such as COVID- 19, must be inhaled or ingested by a person for that person to contract the disease. Thus, transmission of such pathogens can be prevented, mitigated, and/or slowed by decreasing the amount and/or prevalence of the pathogen in areas surrounding the faces of people within the space. This can decrease the volume of space in which the air must be cleaned, filtered, and/or sterilized, while still providing an increased effectiveness of disease transmission prevention. Stated otherwise, instead of attempting to clean all of the area within a given room, it is possible to decrease and/or minimize pathogen transmission by treating only a particular, targeted portion of the room that corresponds to the faces of the people located within the room, such as the breathing zone, which can correspond to the volume with a room that exists from approximately 4.5 feet (approximately 1.4 meters) from the floor to approximately 7.2 feet (approximately 2.2 meters) from the floor.

[0037] The disclosed technology includes air sanitation devices and/or air sanitation systems that can be positioned within a room and is/are configured to clean, filter, and/or sterilize the air within the breathing zone. Referring to FIGs. 1 A-1D, example air sanitation devices 100 are illustrated. The disclosed air sanitation device 100 can be freestanding. For example, the air sanitation device 100 can be configured to be placed on a floor (e.g., as shown in FIGs. 1A or IB), or the air sanitation device 100 can be configured to be placed an elevated surface, such as a desktop or a tabletop (e.g., as shown in FIG. 1C). The air sanitation device 100 can be substantially elongate and substantially tubular, although the disclosed technology is not limited to this shape and can have any other shape. As a nonlimiting example, the air sanitation device 100 can include some or all of the elements and features described in U.S. Patent No. 1 1 ,129,918, the entire contents of which are incorporated herein by reference.

[0038] Regardless of whether the air sanitation device 100 is configured to provide clean air in a specifically targeted area (e.g., the breathing zone), the air sanitation device 100 can be configured to draw in air via an air inlet 1 10 and discharge cleaned air from an air outlet 120. As shown, the air inlet 110 can be located proximate a bottom portion of the air sanitation device 100 (e.g., as shown in FIG. 1A), or the air inlet 110 can be located at a middle location of the air sanitation device 100 (e.g., as shown in FIGs. IB or 1C). The air outlet 120 can be located proximate a top portion of the air sanitation device 100. Alternatively, the air inlet 110 can be located at the top portion of the air sanitation device 100, and/or the air outlet 120 can be located at the bottom portion or a middle location of the air sanitation device 100.

[0039] Optionally, the base section of the air sanitation device 100 can include wheels (not shown), which can help facilitate easy movement and positioning of the air sanitation device 100. One or more of the wheels can be motor driven, which can further facilitate easy movement and positioning of the air sanitation device 100.

[0040] The air sanitation device 100 can include a filter 130 and/or an ultraviolet (UV) cleaning section 140 including one or more UV light sources 142 (e.g., UV-C). The UV light sources 142 can include a single UV light source 142 or an array of multiple UV light sources 142. Regardless, the UV light source(s) 142 can be positioned to expose all or substantially all of any passing air to UV radiation. For example, the UV light sources 142 can be spaced about the periphery of the outer wall of the UV cleaning section 140 and configured to direct UV light inwardly such that passing air is exposed to the UV light. Alternatively or additionally, one or more UV light sources 142 can be located at or near the center of the body section and can be configured to direct UV light outwardly such that passing air is exposed to the UV light. The central UV light source(s) 142 can form a substantially cylindrical shape, a substantially spherical shape, a substantially polygonal shape, or any other shape.

[0041] The UV cleaning section 140 can be arranged to form a swirling airflow path (e.g., a helical flow path arranged around an array of UV light sources 142), which can help increase the exposure time of passing air to outputted UV radiation, while decreasing the overall size of the UV light source portion of the air sanitation device 200. Stated otherwise, the swirling airflow path can provide an airflow path having a distance that is greater than a linear distance of the UV cleaning section 140, enabling the air sanitation device 100 to have a compact design and/or enabling a higher clean rate (or microbe kill rate) for a given power of the UV light source 142 (e.g., by way of the increased exposure time of passing air to outputted UV radiation). Tn addition, the swirling airflow path of the UV cleaning section 140 can provide a centrifugal effect, which can result in larger particles being pushed outwardly toward the inner surface of the outer wall (referred to herein as the “outer wall”) outer wall of the UV cleaning section 140. These larger particles (e.g., particles between approximately 2 micros and approximately 5 microns in size) can be restrained against the outer wall via Van der Waals forces, such that the UV cleaning section 140 can function as a filter. Alternatively or in addition, any larger particles or droplets that settle and/or are restrained on the outer wall of the UV cleaning section 140 can be subjected to a longer exposure to UV radiation, which can increase the clean rate (or microbe kill rate) for those larger particles or droplets.

[0042] The swirling airflow path can be located along an entire length of the UV cleaning section 140 (e.g., along an entire length of the UV light source 142). Alternatively, the swirling airflow path can be located only at an inlet portion of the UV cleaning section 140 (see, e.g., FIG. 8). In such a case, the swirling airflow path can be configured to provide an initial rotational effect on the passing air, and momentum can cause the air to continue to swirl beyond the end of the swirling airflow path for at least a portion of the UV cleaning section 140. As will be appreciated, a swirling airflow path 144 of a shorted length can provide less of a pressure drop but, in some instances, might result in a decreased clean rate (or microbe kill rate) as compared to a swirling airflow path having a comparatively longer length. That being said, depending on the characteristics of the system (e.g., characteristics, dimensions , and/or geometry of the UV cleaning section 140, including that of the UV light source 142 and/or swirling airflow path 144 and/or the characteristics, dimensions , and/or geometry of the housing in which the UV cleaning section 140 is located), the initial swirl created by a swirling airflow path 144 of a shorted length can provide sufficient rotational motion and momentum to the airflow such that that the residence time of the air within the UV cleaning section 140 would be high enough to provide a high clean rate (or microbe kill rate). That is to say, depending on system characteristics, there can be an optimal initial swirling motion (and corresponding size of the swirling airflow path 144) that can enable the same or approximately the same residence time as would a full-length swirling airflow path 144 without the pressure drop of the full-length swirling airflow path 144 or with a decreased pressure drop as compared to that of the full-length swirling airflow path 144. [0043] To help ensure all or substantially all of the passing air is exposed to UV radiation, the swirling airflow path and/or the outer wall of the UV cleaning section 140 can include a reflective material or a reflective coating. For example, the swirling airflow path and/or the outer wall of the UV cleaning section 140 can include polished aluminum or a polytetrafluoroethylene-like (PTFE) material.

[0044] The disclosed technology includes various types of swirling airflow paths. Referring to FTGs. 2A and 2B, the UV cleaning section 140 can include a UV light source 142 that located at or near a central longitudinal axis of the air sanitation device 100. The UV cleaning section 140 can include a swirling airflow path 144 that can be helical. The swirling airflow path 144 can have an inner edge that is proximate the UV light source 142 and an outer edge that is proximate the outer wall of the UV cleaning section 140. As shown in FIG. 2A, at least some of the inner edge can contact or abut the UV light source 142, and/or at least some of the outer edge can contact or abut the outer wall of the UV cleaning section 140. Alternatively or in addition, at least some or all of the inner edge can be spaced apart from the UV light source 142 (i.e., a gap exists therebetween), and/or at least some of the outer edge can be spaced apart from the outer wall of the UV cleaning section 140. As shown in FIGs. 2A and 2B, the width of the swirling airflow path 144 can be substantially constant along some or all of the swirling flow path.

[0045] Alternatively, the width of the swirling airflow path 144 can change along a length of the UV cleaning section 140. For example, as shown in FIG. 3A, the width of the airflow path 144 can decrease from a first width to a second, smaller width. More specifically, the airflow' path 144 can be approximately equal to the distance between the outer wall of the UV cleaning section 140 and the UV light source 142 at a first portion of the airflow path 144, and the width of the airflow path 144 can decrease along a length of the airflow path 144 (e.g., gradually decrease). Alternatively, as shown in FIG. 3B, the width of the airflow path 144 can increase from a first width to a second width. More specifically, the width of the airflow path 144 can increase from the first width to a second width that is approximately equal to the distance between the outer wall of the UV cleaning section 140 and the UV light source 142.

[0046] Alternatively or in addition, the width of the airflow path 144 can increase from a first width to a second width and then decrease from the second width to a third width, as shown in FIG. 4A. Alternatively or in addition, the width of the airflow path 144 can decrease from a first width to a second width and increase from the second width to a third width. The first and third widths can be the same, the first width can be greater than the third width, or the first width can be less than the third width. The outer edge of the airflow path 144 at the first and/or third widths can contact or abut the outer wall of the UV cleaning section 140, or the outer edge of the airflow path 144 at the first and/or third widths can be spaced apart from the outer wall of the UV cleaning section 140. The outer edge of the airflow path 144 at the second width can contact or abut the outer wall of the UV cleaning section 140, or the outer edge of the airflow path 144 at the second width can be spaced apart from the outer wall of the U V cleaning section 140. The inner edge of the airflow path 144 can contact or abut the UV light source 142. Alternatively or in addition, some or all of the inner edge of the airflow path 144 can be spaced apart from the UV light source 142.

[0047] Referring to FIGs. 5A and 5B, some or all of the outer edge of the airflow path 144 can contact or abut the outer wall of the UV cleaning section 140. Alternatively or in addition, some or all of the outer edge of the airflow path 144 can be spaced apart from the outer wall of the cleaning section. At least some of the inner edge of the airflow path 144 can be spaced apart from the UV light source 142. For example, as shown in FIG. 5 A, the inner edge of a first portion of the airflow path 144 can be spaced apart from the UV light source 142, and the inner edge of a second portion of the airflow path 144 can be located nearer the UV light source 142 (e.g., up to and including the inner edge of the airflow path contacting or abutting the UV light source 142) such that the distance between inner edge of the airflow path 144 and the UV light source decreases (e.g., gradually decreases) along a length of the airflow path 144. Conversely, as shown in FIG. 5B, the inner edge of a first portion of the airflow path 144 can be located near the UV light source 142 (e.g., up to and including the inner edge of the airflow path contacting or abutting the UV light source 142) and the inner edge of a second portion of the airflow path 144 can be spaced apart from the UV light source 142 a distance that is greater than a distance at the first portion such that the distance between inner edge of the airflow path 144 and the UV light source increases (e.g., gradually increases) along a length of the airflow path 144.

[0048] Referring to FIG. 6, the distance between the inner edge of the airflow path 144 and the UV light source 142 can increase from a first distance (e.g., up to and including the inner edge of the airflow path contacting or abutting the UV light source 142) to a second distance and can then decrease from the second distance to a third distance (e.g., up to and including the inner edge of the airflow path contacting or abutting the UV light source 142). The first and third distances can be approximately equal. Alternatively, the first distance can be greater than the third distance, or the first distance can be less than the third distance. The inner edge of the airflow path 144 at the first and/or third widths can contact or abut the UV light source 142, or the inner edge of the airflow path 144 at the first and/or third widths can be spaced apart from the UV light source 142. The inner edge of the airflow path 144 at the second width can contact or abut the UV light source 142, or the inner edge of the airflow path 144 at the second width can be spaced apart from the UV light source 142. The outer edge of the airflow path 144 can contact or abut the outer wall of the UV cleaning section 140. Alternatively or in addition, some or all of the outer edge of the airflow path 144 can be spaced apart from the outer wall of the UV cleaning section 140.

[0049] Referring now to FIG. 7, the UV cleaning section 140 can include a multiplehelix airflow path 144, such as a double helix, a triple helix, or the like. As illustrated, the airflow path 144 can be a double helix having a first pathway 144a and a second pathway 144b. Further, it is contemplated that the hehx(es) can be right-handed or left-handed.

[0050] The airflow path 144 can have a pitch angle relative a horizontal plane intersecting the lowest portion of a given location of the airflow path 144. The pitch angle can be constant along the length of the airflow path 144. Alternatively, the pitch angle can change along the length of the airflow path. For example, the pitch angle can increase from a first pitch angle to a second pitch angle, and/or the pitch angle can decrease from a third pitch angle to a fourth pitch angle. The pitch angle of a given location along the length of the airflow path 144 can be approximately 15°, approximately 30°, approximately 45°, approximately 60°, or approximately 75°. Alternatively or in addition, the pitch angle of a given location along the length of the airflow path 144 can be in a range between approximately 5° and approximately 15°, in a range between approximately 15° and approximately 25°, in a range between approximately 25° and approximately 35°, in a range between approximately 35° and approximately 45°, in a range between approximately 45° and approximately 55°, in a range between approximately 55° and approximately 65°, or in a range between approximately 65° and approximately 75°.

[0051] The UV cleaning section 140 can include any number sections of the disclosed airflow path 144 (e.g., a first section as shown in FIG. 2A and a second section as shown in FIG. 6). The sections can be arranged to seamlessly transition from one to the other (i.e., without gaps in the airflow path 144). Alternatively, the UV cleaning section 140 can include a plurality of separate and discrete sections of airflow paths 144 that each separated by a gap.

[0052] The air sanitation device 100 one or more air movement devices 150, which can include a blower, a fan, an induction fan, a variable speed fan, or any other device configured to draw in and/or push air. While the filter 130, the UV cleaning section 140, and air movement device 150 are shown as being disposed within the body section, one, some, or all of these components can be located in different portions of the air sanitation device 100 (e.g., in the base section). Further, the various components can be provided in a sequential order .

[0053] After air passes through the filter 130 and/or the UV cleaning section 140, the air movement device 150 can push the cleaned air out of the air sanitation device 200 and back into the surrounding environment. The cleaned air can be discharged via one or more air outlets 120. The air outlets 120 can be located at a height that is at, near, or above the top of the breathing zone, such as at a height that is greater than or equal to approximately 7 feet. For example, the air outlets 120 can be located at a height that is in a range from approximately 7 to approximately 12 feet, with respect to the ground. As will be appreciated, discharging air from a high position that is at, near, or above the top of the breathing zone can help create a downflow effect that will push aerosols out of the breathing zone.

[0054] One or more of the air outlets 120 can be configured to discharge the cleaned air at a downward angle (e.g., via an air distribution device comprising one or more louvers, one or more dampers, or the like). For example, the air outlets 120 can be configured to discharge the cleaned air at a downward angle that is in a range from approximately 5 degrees to approximately 30 degrees. A given air outlet 120 can include one or more air distribution devices (e.g., one or more lovers, dampers, vanes, or foils) configured to direct the cleaned air in a desired direction. The downward angle of the discharged air can help create the downflow effect. The air outlets 120 can be arranged such that adjacent outlets discharge cleaned air in opposite rotational directions (e.g., via one or more internal radial swirl vanes in a given air outlet 120).

[0055] Alternatively or additionally, one or more of the air outlets 120 can be configured to discharge the cleaned air at an upward angle. Such a configuration can, for example, be configured to use a ceiling of the room in which the air sanitation device 100 is located to help guide flow of discharged air. That is, the cleaned air can be discharged upwardly toward a ceiling to rebound the ceiling at a desired angle to create a desired downward flow effect. This can, in some instances, enable air to flow or glide a longer lateral distance, instead of the discharged air quickly falling toward the ground. This can, in turn, ultimately enable a downward effect that can efficiently push pathogens out of the breathing zone. As a non-limiting example, the air outlets 120 can be configured to discharge the cleaned air at an upward angle that is in a range from approximately 1 degree to approximately 80 degrees. As a more specific example, the air outlets 120 can be configured to discharge the cleaned air at an upward angle of approximately 45 degrees. A given air outlet 120 can include one or more air distribution devices (e.g., one or more louvers, dampers, vanes, or foils) configured to direct the cleaned air in a desired direction. The air outlets 120 can optionally be arranged such that adjacent outlets discharge cleaned air in opposite rotational directions (e.g., via one or more internal radial swirl vanes in a given air outlet 120). To ensure the air rebounds off the ceiling at the angle, the air sanitation device 100 can be configured such that the air outlets 120 are positioned or positionable at a height that is in a range from approximately 0.5 feet to approximately 2 feet less than the height of the ceiling of the room in which the air sanitation device 100 is located. Since typical residential rooms and office spaces have a ceiling height in the range from approximately 9 feet to approximately 14 feet, the air sanitation device 100 can be configured such that the outlets 228 are positioned or positionable at a height that is in a range from approximately 7 feet to approximately 12 feet. That being said, it is contemplated that the air outlets 120 can be positioned or positionable at heights outside of this particular range.

[0056] Alternatively or additionally, the one or more of the air outlets 120 can be configured to discharge the cleaned air at a substantially horizontal direction (i.e., 0 degrees with respect to horizontal). For example, the air sanitation device 100 can be configured to discharge air from one or more air outlets 120 located proximate the top of, or above, the breathing zone (e.g., proximate the top of the body section), and the air outlets 120 can be configured to discharge cleaned air in a generally horizontal direction. The one or more air outlets 120 can comprise slots disposed in an outer wall of a discharge portion of the air sanitation device 100. The air outlets 120 can be situated about the entire perimeter of the discharge portion. Alternatively, the air outlets 120 can be located in one or more particular regions of the discharge portion, which can help effect discharge of cleaned air in a desired direction. For example, the air outlets 120 can be located in a section comprising approximately 25% of the discharge portion’s perimeter. As another example, the air outlets 120 can be located in a section comprising approximately 50% of the discharge portion’s perimeter. Additionally or alternatively, one or more dampers can be included. Each damper can be opened to permit the discharge of cleaned air through one or more particular air outlets 120, or the damper can be closed to partially or fully cover one or more particular air outlets 120 to prevent or inhibit the discharge of cleaned air through the one or more particular air outlets 120.

[0057] As will be appreciated, air sanitation devices 100 providing upward discharge angles can be particularly useful for large, open spaces (e.g., open office spaces) in which it is desirable for the cleaned air to travel relatively long distances. On the other hand, air sanitation devices 100 providing downward discharge angles can be particularly useful for smaller spaces (e.g., an individual office) in which it is unnecessary for the cleaned air to travel relatively long distances.

[0058] The air movement device 150 can be configured to output air at a velocity that is less than approximately 5 ft/s, which can help avoid the creation of recirculation flows and elevations gains of the discharged air. For example, the air movement device 150 can be configured to output air at a velocity that is in a range from approximately 1 ft/s to approximately 5 ft/s. Alternatively or additionally, the air movement device 150 can be configured to output an airflow between approximately 150 cubic feet per minute (CFM) and approximately 200 CFM. As a more specific example, the air movement device 150 can be configured to output an airflow of approximately 175 CFM.

[0059] The air sanitation device 200 can include one or more sensors configured to detect the presence of aerosols in the air, which can include a radiometer, an infrared sensor, an optical counting sensor (e.g., based upon either light scattering, light obscuration, and/or direct imaging), a condensation particle counter, a differential mobility particle sizer (e.g., a scanning mobility particle sizer, a fast mobility particle sizer), or the like. The air sanitation device 200 can be configured engage/disengage the UV light source 224 and/or air movement device 150 based on the presence and/or concentration or aerosols in the air. For example, if the detected concentration of aerosols is above a first predetermined threshold, the air sanitation device 200 can be configured engage the UV light source 224 and/or air movement device 150, and if the detected concentration of aerosols is less than or equal to a second predetermined threshold, the air sanitation device 200 can be configured disengage the UV light source 224 and/or air movement device 150. The first and second predetermined threshold can be the same threshold. Alternatively, the first predetermined threshold can be different from the second predetermined threshold. For example, the first predetermined threshold can be less than the second predetermined threshold. Conversely, the first predetermined threshold can be greater than the second predetermined threshold.

[0060] Moreover, the air sanitation device 200 can be configured to adjust the power and/or speed of the air sanitation device 200 based on the detected concentration of aerosols. For example, the air sanitation device 200 can increase the power and/or speed (e.g., of the air movement device 150) if the detected concentration of aerosols is high, and the air sanitation device 200 can decrease the power and/or speed if the detected concentration of aerosols is relatively lower but still above at least one of the first or second predetermined thresholds.

[0061] The disclosed technology can simultaneously suppress and dilute pathogens and/or infection particles present in the air of an indoor environment. As will be appreciated, locating the air inlets 110 at or below the breathing zone can help create a downward flow arrangement of air within the indoor environment; which can result in suppression of suspended aerosols in the air by drawing the suspended aerosols toward the air inlets 110 , thereby removing the aerosols from the breathing zone. After intake, the air can be filtered and/or exposed to UV light, which can kill pathogens and sanitize the air. The sanitized air can be discharged (e.g., at, near, or above the top of the breathing zone), and the sanitized air optionally can be discharged at a downward angle. Introducing sanitized air into the indoor environment can help dilute the aerosols. The downward flow of the discharged, sanitized air from a high position can help suppress aerosols by pushing them downward toward the ground and out of the breathing zone. With the aerosols pushed to ground level, the air including the aerosol can be drawn into the air inlets 110, repeating the process.

[0062] Alternatively, the air inlets 110 can be disposed proximate a middle portion and/or a top portion of the air sanitation device 100, and the air sanitation device 100 can be configured to discharge air proximate a middle portion and/or bottom portion of the air sanitation device 100. The air inlets 110 of the air sanitation device 100 can be located at one or more heights that are within the breathing zone. For example, a lower air inlet 110 can be located at approximately 5 feet from ground and an upper air inlet 110 can be located at approximately 7 feet from ground. Thus, the air sanitation device 100 can be configured to draw in aerosols and/or microdroplets before the aerosols and/or microdroplets leave (e.g., initially leave) or enter the breathing zone. Thus, circulation of air exhaled from a person can be caught by the air sanitation device 100 before it becomes circulated about the space, thereby reducing the amount of travel experienced by a given microdroplet. This can decrease the likelihood that another person will inhale or ingest the microdroplet. The air movement device 150 can move air from the air inlets 110 and downwardly through the body of the air sanitation device 100. The air movement device 150 can move air through the filter 130 and/or through the UV cleaning section 140. The air movement device 150 can then push cleaned air out of the air sanitation device 100 via the air outlets 120, which can be located at a height that is in the breathing zone, at the bottom of the breathing zone, or less than the bottom of the breathing zone (e.g., less than approximately 4.5 feet). For example, the air outlets 120can be located at a height that is less than or equal to approximately 2 feet above the ground. As another example, the air outlets 120can be located at a height that is less than or equal to approximately 1 foot above the ground. The air outlets 120can discharge the cleaned air in a substantially horizontal direction. Alternatively or in addition, the air outlets 120can discharge the cleaned air in an upward direction (e.g., via an air distribution device comprising one or more louvers, one or more dampers, or the like), such as in a direction having an upward angle in the range from approximately 5 degrees to approximately 15 degrees, with respect to horizontal. The air movement device 150 can be configured to output air at a velocity that is less than approximately 5 ft/s, which can help avoid the creation of recirculation flows and elevations gains of the discharged air. For example, the air movement device 150 can be configured to output air at a velocity that is in a range from approximately 1 ft/s to approximately 5 ft/s. As a more specific example, the air movement device can be configured to output air at approximately 2 ft/s. Alternatively or in addition, the air movement device 150 can be configured to output airflow between approximately 50 CFM and approximately 100 CFM. As a more specific example, the air movement device 150 can be configured to output an airflow between approximately 70 CFM and approximately 75 CFM.

[0063] While the UV cleaning section 140 (including the airflow paths 144) has been described to this point in the context of an air sanitation device 100, the disclosed technology is not so limited. For example, the UV cleaning section 140, including the UV light source 142 and one or more airflow paths 144, can be integrated into a traditional HVAC system (e.g., a central HVAC system). The UV cleaning section 140 can be integrated into a component or unit of a HVAC system, such as an air intake unit, an air handler, a cabinet, a housing, or the like. Alternatively or in addition, the UV cleaning section 140 can be installed in, or otherwise integrated into, a duct, a pipe, or the like . The UV cleaning section 140 can be a retrofit system that can be installed in an existing, already installed HVAC system. The UV cleaning section 140 can be located upstream from a fan or blower of the HVAC system. Alternatively or in addition, the UV cleaning section 140 can be located downstream from the fan or blower of the HVAC system. The drawings (e.g., FIGs. 2A-7) have been referenced to generally describe the UV cleaning section 140 as being installed in an air sanitation devices 100 (e g., a standalone device). However, as will be understood, the drawings can also representation inclusion of the UV cleaning section 140 in an HVAC system. For example, the sidewalls depicted in each of FIGs. 2A- 7 can represent inner walls of an air sanitation device 100, or the sidewalls can represent inner walls of a cabinet, a housing, an air intake unit, an air handler, a duct, a pipe, or any other component of an HVAC system through which air can flow.

[0064] As described herein, the UV cleaning section 140 can be included in an air sanitation device 100 or an HVAC system at any location through which air flows. As illustrated in FIG. 8, the UV cleaning section 140 can be located proximate an air inlet. However, the UV cleaning section 140 can be located elsewhere and/or extend along a greater distance of the air sanitation device 100 or HVAC system. Additionally, multiple UV cleaning sections 140 (e.g., two, three, four, or more) can be located within the air sanitation device 100 or HVAC system.

[0065] In this description, numerous specific details have been set forth. It is to be understood, however, that implementations of the disclosed technology may be practiced without these specific details. In other instances, well-known methods, structures, and techniques have not been shown in detail in order not to obscure an understanding of this description. References to “one embodiment,” “an embodiment,” “one example,” “an example,” “some examples,” “example embodiment,” “various examples,” “one implementation,” “an implementation,” “example implementation,” “various implementations,” “some implementations,” etc., indicate that the implementation(s) of the disclosed technology so described may include a particular feature, structure, or characteristic, but not every implementation necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one implementation” does not necessarily refer to the same implementation, although it may.

[0066] Further, certain methods and processes are described herein. It is contemplated that the disclosed methods and processes can include, but do not necessarily include, all steps discussed herein. That is, methods and processes in accordance with the disclosed technology can include some of the disclosed while omitting others. Moreover, methods and processes in accordance with the disclosed technology can include other steps not expressly described herein.

[0067] Throughout the specification and the claims, the following terms take at least the meanings explicitly associated herein, unless otherwise indicated. The term “or” is intended to mean an inclusive “or.” Further, the terms “a,” “an,” and “the” are intended to mean one or more unless specified otherwise or clear from the context to be directed to a singular form. By “comprising,” “containing,” or “including” it is meant that at least the named element, or method step is present in article or method, but does not exclude the presence of other elements or method steps, even if the other such elements or method steps have the same function as what is named.

[0068] As used herein, unless otherwise specified, the use of the ordinal adjectives “first,” “second,” “third,” etc., to describe a common object, merely indicate that different instances of like objects are being referred to and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

[0069] While certain examples of this disclosure have been described in connection with what is presently considered to be the most practical and various examples, it is to be understood that this disclosure is not to be limited to the disclosed examples, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0070] This written description uses examples to disclose certain examples of the technology and also to enable any person skilled in the art to practice certain examples of this technology, including making and using any apparatuses or systems and performing any incorporated methods. The patentable scope of certain examples of the technology is defined in the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

[0071] Embodiment 1 may include an air sanitation system comprising: an ultraviolet (UV) cleaning section comprising: a UV light source; and an airflow path rotating about at least a portion of the UV light source such that the airflow path imparts a swirling effect on air passing therethrough; and an air movement device configured to move air into the air sanitation system via an air inlet, through the UV cleaning section, and out of the air sanitation system via an air outlet; wherein the air outlet is disposed at an upper portion of the air sanitation system, and the air inlet is disposed at a lower portion of the air sanitation system.

[0072] Embodiment 2 may include Embodiment 1, wherein the air sanitation system is housed in a standalone air sanitation device.

[0073] Embodiment 3 may include any one of Embodiments 1 to 2, wherein the air outlet is located at a height that is greater than or equal to approximately 7 feet with respect to a bottom of the air sanitation device, and the air inlet is located at a height that is less than approximately 4.5 feet with respect to the bottom of the air sanitation device.

[0074] Embodiment 4 may include any one of Embodiments 1 to 3, wherein the air sanitation system is a coupled to aheating, ventilation, and air conditioning (HVAC) system.

[0075] Embodiment 5 may include any one of Embodiments 1 to 4, wherein airflow path forms a helix.

[0076] Embodiment 6 may include any one of Embodiments 1 to 5, wherein the airflow path has a first width at a first location along the airflow path and a second width at a second location along the airflow path, the first width being greater than the second width.

[0077] Embodiment 7 may include any one of Embodiments 1 to 6, wherein: the airflow path has a first width at a first location along the airflow path, a second width at a second location along the airflow path, a third width at a third location along the airflow path, the first width being greater than the second width and the third width being greater than the second width. [0078] Embodiment 8 may include any one of Embodiments 1 to 7, wherein the first width is different from the third width.

[0079] Embodiment 9 may include any one of Embodiments 1 to 8, wherein the airflow path has an inner edge, wherein at least a portion of the inner edge abuts the UV light source.

[0080] Embodiment 10 may include any one of Embodiments 1 to 9, wherein the airflow path has an inner edge and at least a portion of the inner edge is spaced apart from the UV light source.

[0081] Embodiment 11 may include any one of Embodiments 1 to 10, wherein the airflow path has an outer edge and at least a portion of the outer edge abuts the UV light source.

[0082] Embodiment 12 may include any one of Embodiments 1 to 11, wherein the airflow path has an inner edge and at least a portion of the inner edge is spaced apart from the UV light source.

[0083] Embodiment 13 may include any one of Embodiments 1 to 12, wherein the airflow path is one of a plurality of airflow paths included in the UV cleaning section, at least one of the plurality of airflow paths being separated from an adjacent airflow path by a gap.

[0084] Embodiment 14 may include any one of Embodiments 1 to 13, wherein the airflow path has a pitch angle relative a horizontal plane intersecting the lowest portion of a given location of the airflow path, the pitch angle being constant along a length of the airflow path.

[0085] Embodiment 15 may include any one of Embodiments 1 to 14, wherein the airflow path has a pitch angle relative a horizontal plane intersecting the lowest portion of a given location of the airflow path, the pitch angle vary ing between approximately 15° and approximately 75° along a length of the airflow path.

Claims

CLAIMS What is claimed is:

1. An air sanitation system comprising: an ultraviolet (UV) cleaning section comprising: a UV light source; and an airflow path rotating about at least a portion of the UV light source such that the airflow path imparts a swirling effect on air passing therethrough; and an air movement device configured to move air into the air sanitation system via an air inlet, through the UV cleaning section, and out of the air sanitation system via an air outlet; wherein the air outlet is disposed at an upper portion of the air sanitation system, and the air inlet is disposed at a lower portion of the air sanitation system.

2. The air sanitation system of claim 1, wherein the air sanitation system is housed in a standalone air sanitation device.

3. The air sanitation system of any one of claims 1 to 2, wherein the air outlet is located at a height that is greater than or equal to approximately 7 feet with respect to a bottom of the air sanitation device, and the air inlet is located at a height that is less than approximately 4.5 feet with respect to the bottom of the air sanitation device.

4. The air sanitation system of any one of claims 1 to 3, wherein the air sanitation system is a coupled to a heating, ventilation, and air conditioning (HVAC) system.

5. The air sanitation system of any one of claims 1 to 4, wherein airflow path forms a helix.

6. The air sanitation system of any one of claims 1 to 5, wherein the airflow path has a first width at a first location along the airflow path and a second width at a second location along the airflow path, the first width being greater than the second width.

7. The air sanitation system of claim 6, wherein: the airflow path has a first width at a first location along the airflow path, a second width at a second location along the airflow path, a third width at a third location along the airflow path, the first width being greater than the second width and the third width being greater than the second width.

8. The air sanitation system of claim 7, wherein the first width is different from the third width.

9. The air sanitation system of any one of claims 1 to 8, wherein the airflow path has an inner edge, wherein at least a portion of the inner edge abuts the UV light source.

10. The air sanitation system of any one of claims 1 to 9, wherein the airflow path has an inner edge and at least a portion of the inner edge is spaced apart from the UV light source.

11. The air sanitation system of any one of claims 1 to 10, wherein the airflow path has an outer edge and at least a portion of the outer edge abuts the UV light source.

12. The air sanitation system of any one of claims 1 to 11, wherein the airflow path has an inner edge and at least a portion of the inner edge is spaced apart from the UV light source.

13. The air sanitation system of any one of claims 1 to 12, wherein the airflow path is one of a plurality of airflow paths included in the UV cleaning section, at least one of the plurality of airflow paths being separated from an adjacent airflow path by a gap.

14. The air sanitation system of any one of claims 1 to 13, wherein the airflow path has a pitch angle relative a horizontal plane intersecting the lowest portion of a given location of the airflow path, the pitch angle being constant along a length of the airflow path.

15. The air sanitation system of any one of claims 1 to 14, wherein the airflow path has a pitch angle relative a horizontal plane intersecting the lowest portion of a given location of the airflow path, the pitch angle varying between approximately 15° and approximately 75° along a length of the airflow path.