AIR SANITIZING SYSTEM AND METHOD FOR CONTROLLING THE SAME

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]This application claims priority under 35 U.S.C. §§ 119(e), 120 to U.S. Application No. 63/766,729, filed on Mar. 4, 2025, and U.S. application Ser. No. 18/328,315, filed on Jun. 2, 2023, which application are incorporated by reference herein in their entireties.

CITATIONS

[0002]International Application No. PCT/US2023/082076, filed Dec. 1, 2023, is incorporated by reference herein in its entirety.

FIELD

[0003]The present disclosure relates to an air sanitizing system. More particularly, a system and method for controlling a UV-C sanitizing apparatus arranged within an HVAC duct.

BACKGROUND

[0004]Indoor air filtration is well known within the art. In expensive filtration apparatuses, mechanical filtration is commonly utilized, such as the use of filters. It is well known that UV-wavelength light also provides radiation filtration of air.

[0005]The use of ultraviolet (UV) light, particularly in the UV-C wavelength range, for sanitizing air is known. While effective at neutralizing microorganisms, the light sources themselves, especially modern light-emitting diodes (LEDs), present operational challenges.

[0006]Previous attempts to utilize UV treatment in air ducts have involved complex apparatuses. For instance, some systems use a baffle to direct airflow towards a negative oxygen enhancer and employ a temperature sensor to deactivate the enhancer when the air is below a predetermined temperature. Such systems are complex and their control logic is not directed towards managing the operational efficiency or thermal health of the UV light source itself.

[0007]Other air purification devices utilize an internal fan to move air through a housing that contains a UV lamp. These devices, however, do not adequately address the considerable heat generated by the UV light sources. The prolonged exposure to this self-generated heat can degrade the light source, reducing its longevity and altering its germicidal effectiveness, and their continuous operation is not energy-efficient.

[0008]Therefore, there is a need in the art for an improved air sanitizing apparatus for use in an HVAC system that addresses the challenges of thermal degradation of the UV light source and improves operational efficiency. A system is needed that can be integrated into existing ductwork while providing for both effective heat management and intelligent control of the UV sanitation process.

[0009]Still further, there is a need to optimize efficiency of a UV light apparatus, particularly, automatically controlling one or more of the intensity or operation (on or off) of one or more of the individual LEDs that make up a UV light module of the UV light apparatus.

SUMMARY

[0010]This disclosure provides systems and methods for sanitizing air within a heating, ventilation, and air conditioning (HVAC) duct. An apparatus, configured for installation within the duct, comprises a UV-C light module secured to a heat sink. An air scoop is arranged to capture a portion of the airflow within the duct and direct it across the heat sink to provide thermal management for the UV-C light module. The operation of the apparatus is governed by a control system having a microprocessor that processes data from one or more sensors to intelligently control the output of the UV-C light module based on detected environmental conditions.

[0011]Certain aspects of the disclosure are directed to providing efficient and reliable air sanitation. An objective is to manage the thermal output of the UV-C light source by using the HVAC system's own airflow, thereby contributing to the operational longevity of the light-emitting components. Another objective is to provide for automated control of the apparatus. In some embodiments, this is accomplished by using a temperature sensing arrangement to detect the presence of airflow, allowing the system to operate the UV-C light module when the HVAC fan is active. In other embodiments, a cellular detection module is used to estimate building occupancy by detecting signals from nearby devices, which allows the microprocessor to adjust the UV-C light module's on/off state or intensity in response to the number of occupants. Further aspects include fault monitoring capabilities to detect and signal operational anomalies within the system.

[0012]In one aspect, an air sanitizing system comprises an air scoop adapted for securement to an internal surface of an HVAC duct. The air scoop includes an inlet end, an outlet end, and a bracket extending distally therefrom. A UV light module is secured to the bracket, and a heat sink is secured to the UV light module proximate the outlet end. The system also includes a control board in communication with the UV light module, where the control board has a microprocessor and one or more cellular detection modules. The microprocessor is programmed to detect cellular signals via the modules and, in response to a quantity of detected signals, communicates to the UV light module to turn on at a determinable intensity. This allows the system to provide air sanitation that is responsive to the estimated occupancy of a space.

[0013]In some embodiments, the digital signal or cellular detection module is a Wi-Fi sniffer, and the digital or cellular signals it detects are Wi-Fi probe requests. This provides a specific and effective means for detecting the presence of Wi-Fi enabled devices. The UV light module may be secured to a printed circuit board and can include a plurality of LED light modules, each arranged to emit germicidal UV-C radiation.

[0014]To enhance thermal management, the heat sink may further comprise a plurality of radiator fins arranged to extend beyond the UV light module. These fins can have an upper portion disposed within the air scoop and a lower portion that extends past the outlet end of the air scoop, maximizing contact with both the directed airflow from the scoop and the main airflow within the duct. In other configurations, the UV light module may comprise a plurality of individual heat sinks secured to the printed circuit board, with each individual heat sink disposed adjacent to one of the plurality of LED light modules for localized cooling. Functionally, the air scoop is arranged to partially obstruct air passing through the duct and direct that obstructed portion of the air over the heat sink.

[0015]In another aspect of the disclosure, the system includes a temperature-based control mechanism. This configuration includes a temperature sensor arranged on the UV light module, which is in communication with an ambient temperature sensor and a heat-source temperature sensor. The microprocessor communicates with these sensors and is programmed to act based on their readings. For instance, when the temperature readings of the ambient and heat-source sensors are closer in degrees, indicating airflow, the microprocessor can communicate to the UV light module to turn on. Conversely, when the temperatures are farther apart in degrees, indicating a lack of airflow, the microprocessor communicates to the UV light module to turn off. This control logic can also be combined with occupancy sensing, such that the microprocessor turns the UV light module off when no cellular signals are detected, even if airflow is present.

[0016]To improve system reliability, some embodiments include a notification device in communication with the microprocessor. The microprocessor is programmed to monitor one or more operational parameters for a fault condition and, upon detecting such a condition, will activate the notification device, which may be an audio alarm or a visual indicator. For ease of installation and protection, the control board may be housed in a dedicated control module arranged on the HVAC duct and connected to an external power source.

[0017]The disclosure also provides a method for sanitizing air flow within an HVAC duct. The method includes the steps of providing the UV-C air scoop apparatus within the duct and controlling its operation. The control may be based on one or more of two primary strategies: detecting cellular signals in proximity to the apparatus to gauge occupancy, or determining that an ambient temperature and a heat-source temperature are within a predetermined range of degrees to confirm airflow.

[0018]In a more detailed aspect of the method, the intensity of the UV light can be controlled in a tiered manner based on the number of detected cellular signals. This includes turning the UV light on when a first signal threshold is exceeded, raising the intensity when a second, higher threshold is exceeded, decreasing the intensity when the signal count falls below the second threshold, and turning the light off when no signals are detected. The method also includes the specific steps of turning the UV light module on when the ambient and heat-source temperatures are within the predetermined range, and turning it off when they are not. A comprehensive method may combine these strategies, using temperature readings to enable the system and then using cellular signal counts to modulate the intensity, while turning the system off if either airflow ceases or no cellular signals are detected.

[0019]In a further aspect, a control system for such an air sanitizing apparatus is described. The control system comprises a microprocessor, at least one sensor interface, and an output interface. The sensor interface is configured to receive data from either a temperature sensing arrangement or a cellular detection module. The microprocessor is programmed to generate a control signal for the UV light module based on this data. It may do so by calculating a temperature differential to control the on/off state of the module, or by determining a quantity of detected signals to control either the on/off state or the intensity of the module.

[0020]These and other objects, features, and advantages of the present invention will become readily apparent upon a review of the following detailed description of the invention, in view of the drawings and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]Various embodiments are disclosed, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, in which:

[0022]FIG. 1A is a perspective view of an HVAC duct;

[0023]FIG. 1B is a front view of the present invention;

[0024]FIG. 2A is a top view of the HVAC duct shown in FIG. 1A;

[0025]FIG. 2B is a cross-sectional view of the HVAC duct taken generally along line 2B-2B in FIG. 2A, with the present invention installed therein;

[0026]FIG. 3A is a top perspective view of UV-C air scoop apparatus 100 of the present invention;

[0027]FIG. 3B is a bottom perspective view of UV-C air scoop apparatus 100 of the present invention;

[0028]FIG. 4A is a front view of UV-C air scoop apparatus 100 of the present invention;

[0029]FIG. 4B is a cross-sectional view of UV-C air scoop apparatus 100 taken generally along line 4B-4B in FIG. 4A;

[0030]FIG. 5 is an exploded view of UV-C air scoop apparatus 100;

[0031]FIG. 6 is a partial exploded view of PCB board 142 taken from FIG. 5, also illustrating an enlarged view of LED heat sink 161;

[0032]FIG. 7A is a perspective view of control module 150;

[0033]FIG. 7B is a side view of FIG. 7A;

[0034]FIG. 7C is a perspective view of control module 150 without cover 152;

[0035]FIG. 8 is a high-level circuit schematic of the present invention;

[0036]FIG. 9 is a cross-sectional view of the HVAC duct taken generally along line 2B-2B in FIG. 2A specifically showing air flow pathways through HVAC duct 200;

[0037]FIG. 10 is a high-level flow diagram of the operation of the present invention;

[0038]FIG. 11 is a cross-sectional view taken generally along line 4B-4B in FIG. 4A;

[0039]FIG. 12 is a representative diagram of a system used to control the operation of integrated with the UV-C air scoop apparatus 100;

[0040]FIG. 13 is a high-level flow diagram of the system shown in FIG. 12; and,

[0041]FIG. 14 is a method of controlling UV-C air scoop apparatus 100.

DETAILED DESCRIPTION

[0042]At the outset, it should be appreciated that like reference numerals in the various drawings identify identical or functionally similar structural elements. It is to be understood that the claims are not limited to the disclosed aspects, and this disclosure is not limited to the particular methodologies, materials, and modifications described. The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. Those skilled in the art will understand that any suitable materials or methods, now known or hereafter developed, may be used in forming or practicing the disclosed embodiments.

[0043]Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The word “exemplary” means “serving as an example, instance, or illustration,” and any implementation described as such is not necessarily to be construed as preferred or advantageous over other implementations. Furthermore, if the specification states a component or feature “may,” “can,” “could,” “should,” “preferably,” or “optionally” possesses a characteristic, that component or feature is not required to be included or to have that characteristic. For instance, the control system may operate based on temperature differential, cellular signal detection, or a combination of both; these are presented as optional and alternative control strategies. Directional adjectives, such as “upper,” “lower,” “right,” and “left,” are to be interpreted in view of the corresponding drawings and are intended to be exemplary.

[0044]The term “substantially” is used to accommodate manufacturing tolerances and minor variations that do not materially affect the function of a feature, such as a “substantially downward” curve of the air scoop or a “substantially rectangular” duct. The term “proximate” is synonymous with terms such as “nearby,” “close,” and “adjacent.” The terms “having,” “has,” “including,” and “containing” are to be interpreted as open-ended terms substantially synonymous with “comprising.”

[0045]It should be understood that the use of “or” is non-exclusive unless stated otherwise, meaning it can signify one, the other, or both items in a series. Furthermore, as used herein, the phrases “comprises at least one of” and “comprising at least one of” in combination with a list of elements is intended to mean that the system or element includes one or more of the elements from the list. For example, a control system comprising at least one of a temperature sensor or a cellular detection module is intended to be construed as a system comprising a temperature sensor; a system comprising a cellular detection module; or a system comprising both a temperature sensor and a cellular detection module.

[0046]The systems and methods described herein, particularly the functions of the control system (150) and its associated modules, may be implemented in hardware, software, firmware, or any combination thereof. As used herein, a “processor,” such as the microcontroller (302), may include one or more general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices. The processor is configured to execute instructions stored in a memory to perform the steps and functions described.

[0047]The terms “memory” and “computer-readable medium” may include any available media that can be accessed by the processor, including both volatile and non-volatile media, removable and non-removable media. A non-transitory computer-readable medium includes, but is not limited to, random-access memory (RAM), read-only memory (ROM), EEPROM, flash memory, or other memory technology, as well as optical and magnetic storage devices. The methods and processes described, including those illustrated in flow diagrams, may be embodied as a set of instructions on such a computer-readable medium that, when executed by the processor, cause the processor to control the aforementioned hardware components and perform the described operations.

[0048]Adverting now to the figures. The following description should be taken in view of FIGS. 1A and 2B. FIG. 1A illustrates a perspective view of HVAC duct 200. FIG. 1B illustrates a front view of the heat duct shown in FIG. 1A having UV-C air scoop apparatus 100 attached therein. FIG. 2A illustrates a top view of HVAC duct 200 having UV-C air scoop apparatus 100 attached therein and FIG. 2B is a cross-sectional view of the duct, taken generally along line 2B-2B in FIG. 2A.

[0049]Although FIGS. 1A-2B illustrate HVAC duct 200 having a generally rectangular configuration, it should be appreciated that HVAC duct 200 may comprise a circular, tubular configuration, where UV-C air scoop apparatus 100 may be adapted to include a curvature to accommodate the curved configuration of the HVAC duct. It should be noted that the illustrations of HVAC duct 200 are portions of an entire HVAC duct system, and that other shapes of ducts are considered to be within the scope of the appended claims.

[0050]HVAC duct 200 is generally formed by top member 210, first side member 211, second side member 212, and bottom member 213. HVAC duct 200 has inlet end 214 and outlet end 215. Inlet end 214 is defined as the end of HVAC duct 200 that air flows into and outlet end 215 is defined as the end of HVAC duct 200 that air flows out of. In other words, inlet end 214 represents the inflow portion of HVAC duct 200, that is, the section of an HVAC duct system that is attached to, or begins, at an air source, e.g., heating, ventilation, and/or air conditioning, whereas outlet end 215 represents the outflow portion of HVAC duct 200, that is, the section of an HVAC duct system that terminates at an outflow vent or exhaust.

[0051]In a preferred embodiment, UV-C air scoop apparatus 100 is arranged to be removably secured to internal surface 210a of top member 210 of HVAC duct 200. In a preferred embodiment, UV-C air scoop apparatus 100 is secured to internal surface 210a via a plurality of screws. However, it should be appreciated that other removable securement means known in the art may be used to secure the apparatus to the duct wall/ceiling. Also arranged on HVAC duct 200 is control module 150 (shown in FIG. 1B) of UV-C air scoop apparatus 100. Control module 150 may be removably secured to internal surface 212a of second side member 212 or removably secured to external surface 212b of second side member 212 or may be disposed within second side member 212 via a cut-out through-bore arranged to accept control module 150 therein.

[0052]As shown in FIG. 2B, UV-C air scoop apparatus 100 is configured to bifurcate incoming air from inlet end 214 between internal surface 210a and internal surface 213a, such that its configuration separates the incoming air flow into upper flow UF and lower flow LF at a plane defined by B, and further, where a portion of upper flow UF is arranged to enter UV-C air scoop apparatus 100 to be directed over the heat sink of UV-C air scoop apparatus 100, discussed further infra.

[0053]The following description should be taken in view of FIGS. 3A and 3B. FIG. 3A is a top perspective view of UV-C air scoop apparatus 100, shown removed from HVAC duct 200 and FIG. 3B is a bottom perspective view of the same. UV-C air scoop apparatus 100 generally comprises air scoop 110, heat sink 130, and UV light module 140. Air scoop 110 includes first side panel 111 and second side panel 112. Air directing portion 113 of air scoop 110 is defined by three sections: mounting portion 113a; contoured portion 113b; and, outlet portion 113c. Air scoop 110 has two ends which respectively designate the preferred directional arrangement of UV-C air scoop apparatus 100 when positioned in HVAC duct 200, inlet end 110a and outlet end 110b. Inlet end 110a is the end of UV-C air scoop apparatus 100 that is arranged to accept, or receive, incoming air and outlet end 110b is the end of UV-C air scoop apparatus 100 that the incoming air leaves UV-C air scoop apparatus 100.

[0054]Air scoop 110 may be comprised of heat-resistant plastics, polymers, or molded plastics. Air scoop 110 could alternatively be comprised of different lightweight metals. In a preferred embodiment, heat sink 130 may be comprised of aluminum. Heat sink 130 may be alternatively comprised of a copper-nickel combination, stainless steel (e.g., 316, 304, or other suitable stainless steel types), copper, Heresite P413-coated aluminum, E-coated aluminum, or other suitable steel alloys.

[0055]The following description should be taken in view of FIGS. 4A and 4B. FIG. 4A is a front view of UV-C air scoop apparatus 100 removed from HVAC duct 200 and FIG. 4B is a cross-sectional view taken generally along line 4B-4B in FIG. 4A. Heat sink 130 is arranged on heat sink mounting surface 121 of mounting bracket 120, where mounting bracket 120 is secured to air scoop 110 (shown in FIG. 5). Heat sink 130 comprises plurality of fins 131, where plurality of fins 131 includes upper portion 133 and lower portion 134. Upper portion 133 of plurality of fins 131 is arranged to be disposed within air scoop 110 and lower portion 134 of plurality of fins 131 is arranged to extend outwardly from outlet end 110b, that is, lower portion 134 is outside of air scoop 110. Plurality of fins 131 are preferably radiator fins which are surfaces that extend from heat sink 130 to increase the rate of heat transfer from UV-C air scoop apparatus 100 by increasing convection. It should be appreciated that, in alternative embodiments where increased heat transfer is needed, plurality of fins 131 could also include heat pipes, that is, fully sealed, passive two-phase heat transfer devices that take advantage of a fluid's high heat of vaporization, contained within the heat pipes, to achieve more efficient heat transfer. As shown in FIG. 4B, a space (SPACE) may be present between internal surface 113e and plurality of fins 131.

[0056]Air scoop 110 includes air directing portion 113. Air directing portion 113 is arranged to direct incoming air into air scoop 110 at inlet end 110a, over plurality of fins 131 of heat sink 130, and out through outlet end 110b. Air directing portion 113 includes three portions: mounting portion 113a; contoured portion 113b; and, outlet portion 113c. Mounting portion 113a is defined as the area of air scoop 110 that is removably secured to internal surface 210a of top member 210 of HVAC duct 200, as shown in FIGS. 1B and 2B. Mounting portion 113a merges into contoured portion 113b which curves mounting surface 113d and internal surface 113e in a substantially downward configuration, towards heat sink 130 and UV light module 140. Contoured portion 113b merges into outlet portion 113c which terminates at outlet end 110b. Heat sink 130 and UV light module 140 are preferably arranged proximate to outlet portion 113c.

[0057]As shown in FIG. 11, which generally illustrates an alternative arrangement of the invention shown in FIG. 4B, specifically, no space (SPACE shown in FIG. 4B) is present between internal surface 113e and plurality of fins 131. This alternative arrangement is generally referred to as a “closed” arrangement. The closed arrangement results in increased air pressure proximate the front of the heat sink, i.e., the surface having the LEDs, thusly creating greater air flow through the heat sink, or the plurality of fins of the heat sink, therefore increasing the temperature mitigation properties of the heat sink. Specifically, the closed arrangement, prevents incoming air from bypassing the plurality of fins, via the space (SPACE) between the fins and the internal surface of the air scoop (shown in FIG. 4B), causing the differential pressure to rise in front of the heatsink (i.e., the surface proximate the LEDs) and rise behind the heatsink, which increases net airflow through the heatsink, thereby generating an appreciable drop in temperature at the LED junction, i.e., UV light module 140.

[0058]FIG. 5 is an exploded view of UV-C air scoop apparatus 100. Air scoop 110 includes mounting bracket 111a of first side panel 111 and mounting bracket 112a of second side panel 112, both of which extend from the respective side panels. Mounting brackets 111a and 112a are arranged to engage first mounting end 123 and second mounting end 124 of mounting plate 120, preferably via screws, however other acceptable mounting means may be contemplated. Heat sink 130 is arranged on heat sink mounting surface 121 (shown in FIG. 4B) of mounting bracket 120. UV light module 140 is arranged to secure to UV light module mounting surface 122, specifically PCB board 142, preferably via screws, however other acceptable mounting means may be contemplated. Arranged on PCB board 142 are plurality of LED heat sinks 160 and plurality of UV LEDs 141, having individual LED lights 141a, 141b, 141c, etc.

[0059]In a preferred embodiment, plurality of LED heat sinks 160 are comprised of copper. Alternatively, plurality of LED heat sinks 160 may be comprised of a copper-nickel combination, stainless steel (e.g., 316, 304, or other suitable stainless steel types), Heresite P413-coated aluminum, E-coated aluminum, aluminum, or other suitable steel alloys.

[0060]Plurality of UV LEDs 141 may comprise any suitable LED rated at approximately 270 to 280 nm wavelength. Possible LEDs may include single LEDs, chip-on-board LEDs, LED strip(s), to a complete LED light source. Examples of suitable LEDs are provided by InternationalLight Technologies, part Nos.: E275-3, E275-3-S, ILT-PWRTYLED.3W, E275-10, E275-10-S, E275-60-Strip, or ILT-PWR-12600P5. It should be appreciated that the above-identified examples of LEDs are intended to be non-limiting in view of the appending claims.

[0061]FIG. 6 illustrates a partial view of PCB board 142 taken from FIG. 5. FIG. 6 also illustrates an enlarged view of LED heat sink 161. Plurality of UV LEDs 141 and plurality of LED heat sinks 160 are arranged on mounting surface 142a of PCB board 142. Mounting surface 142a includes a plurality of inputs, inputs for LED lights 142b and inputs for heat sinks 142c. It should be appreciated that inputs 142b and 143c are in electronic and powered communication with PCB board 142, where PCB board 142 is in electronic and powered communication with control module 150 (shown in FIGS. 7A-7C) . Inputs 142b and 142c are arranged to accept an LED light and an LED light heat sink. It should also be appreciated that inputs 142c may be arranged as mounting positions for plurality of LED heat sinks 160 and may not be in electronic and powered communication with PCB board 142.

[0062]Individual LED light heat sink 161 of plurality of LED heat sinks 160 are arranged to collectively provide additional heat dissipation of the heat generated by plurality of UV LEDs 141 and heat from incoming air traveling towards and through HVAC duct 200, in conjunction with heat sink 130 (shown in FIG. 5). Individual LED light heat sink 161 generally comprises base 163 and plurality of fins 162. Plurality of fins 162 are arranged to extend from base 163. Plurality of fins 162 are preferably radiator fins which are surfaces that extend from Individual LED light heat sink 161 to increase the rate of heat transfer by increasing convection. Mounting surface 164 of base 163 is arranged to engage one of inputs for heat sinks 142c on PCB board 142 and external surface 165 of base 163 is arranged opposite from mounting surface 164.

[0063]The following description should be taken in view of FIGS. 7A through 7C. FIG. 7A illustrates a perspective view of control module 150, FIG. 7B illustrates a side view of control module 150, and FIG. 7C illustrates a perspective view of control module 150 without cover 152. Control module 150 is arranged such that it will receive power from an external power source and communicate the power to UV light module 140. UV-C air scoop apparatus 100 is arranged to be connected to a power source, preferably an alternating voltage supply (VAC) and is also arranged to provide a conversion to a direct voltage supply (VAC to VDC) conversion internally in addition to a VAC bypass to allow VAC current to power components of the present invention in addition to the VDC current. Control module 150 includes internal cavity 153 within main body 151 which is sealed by cover 152. Disposed within internal cavity 153 is control board 155 which is arranged to execute and control UV-C air scoop apparatus 100 and the external components, discussed infra. Control module 150 receives power from power source 300 at 2-pin connector 329, which power will be VAC which is converted by power source 300 to VDC. Also shown in FIG. 7C is sensor board 301, shown in greater detail in FIG. 8 and discussed further, infra.

[0064]FIG. 8 is a high-level circuit schematic of the components of UV-C air scoop apparatus 100. Specifically, FIG. 8 illustrates control module 150, control board 155, UV light module 140, sensor board 301, and power source 300. Power source 300 is preferably arranged to accept VAC and convert the VAC current to VDC current. In a preferred embodiment, power source 300 accepts an approximate minimum of 120 VAC 60 Hz with approximately 10% variation. In alternative embodiments, power source 300 would be capable of a universal input range to cover installation of UV-C air scoop apparatus 100 in all regions, e.g., 90 VAC to 277 VAC at both 60 Hz and 50 Hz. Power source 300 preferably provides an output voltage of 24 VDC +/−5 % under all load conditions. Depending on the wattage of plurality of UV LEDs 141, the output power rating of power source 300 may vary from 100 W-300 W for plurality of UV LEDs 141 having an approximate wattage of 75 W-225 W. Control board 155 also includes buck regulator 328, which is arranged to step down the 24 VDC to approximately 5 VDC to provide 5 VDC power to selected components within control board 155 and/or UV light module 140.

[0065]Microcontroller 302 in a preferred embodiment includes three (3) PWMs (pulse width modulated signal generator) 307, 308, and 309. PWMs 307, 308, and 309 are connected to low pass filter 305, alarm 313, and low pass filter 303, respectively.

[0066]Microcontroller 302 in a preferred embodiment may be an AVR® AVR32DA48, which includes the AVR® processor with hardware multiplier, running capability up to 24 MHz with 32 KB Flash, 4 KB SRAM and 512 bytes of EEPROM in 48-pin packages having TQFP and VQFN package options. It should also be appreciated that microcontroller 302 may comprise any alternative microcontroller that can provide the functionality described herein.

[0067]In a preferred embodiment, microcontroller 302 will include a dedicated communication interface to printed circuit board (PCB) MCU 317 of UV light module 140, via I2C 311 (I2C 311 to 14-pin connector 320 to 14-pin connector 321 to I2C 318 of PCB MCU 317). It should also be appreciated that UART (universal asynchronous receiver-transmitter) 327 may be arranged to allow for external communication from microcontroller 302, e.g., to an external computing device such as a cell phone. PCB MCU 317 is primarily arranged to log faults related to plurality of UV LEDs 141, discussed further infra, which are communicated to microcontroller 302. Depending on the particular fault encountered, either alarm 313 or indicator 312, or both, will be activated. Indicator 312 is arranged to provide a visual alarm, e.g., indicator light, and is connected to PWM x3 310 of microcontroller 302. Indicator 312 in a preferred embodiment is arranged to be able to display a plurality of colors associated with a plurality of different faults. Alarm 313 is arranged to provide an audio alarm and is connected to PWM 308.

[0068]In a preferred embodiment, PCB MCU 317 may be an AVR® ATtiny404 microcontroller, which includes 8-bit AVR® processor with a hardware multiplier, with a running capability up to 20 MHz and 4 KB Flash, 256B SRAM, and 128B of EEPROM in a 14-pin package. It should also be appreciated that PCB MCU 317 may comprise any alternative microcontroller that can provide the functionality described herein.

[0069]Adjustable boost converter 304 is connected to low pass filter 303 and PWM 309 of microcontroller 302. Adjustable boost converter 304 is arranged to supply any voltage necessary to begin driving current through plurality of UV LEDs 141, until a maximum voltage is reached. Adjustable boost converter 304 is preferably arranged to have an approximate maximum output voltage of 60V +/−5%, however it should be appreciated that the approximate maximum output voltage is merely exemplary and one having ordinary skill in the art would appreciate possible alternatives in the practice of the present invention. Microcontroller 302 is arranged to control the output of adjustable boost converter 304 to preferably maintain an approximate minimum of 250 mV as the lowest return voltage of plurality of UV LEDs 141-ensuring maximum efficiency and the lowest heat generation from linear current control 306, however it should be appreciated that the approximate lowest return voltage is merely exemplary and one having ordinary skill in the art would appreciate possible alternatives in the practice of the present invention.

[0070]Linear current control 306 is connected to low pass filter 305 and PWM 307 of microcontroller 302. Linear current control 306 is arranged to regulate the current in each LED of plurality of UV LEDs 141 to maintain a high degree of current accuracy in each of the individual LEDs and to protect the individual LEDs. PWM 307 of microcontroller 302 is arranged as a single filtered PWM output to each linear current control circuit of the linear current control 306, driving each of individual current control circuits with the same reference. Linear current control 306 is arranged to maintain an approximate LED current within 10 mA of the reference input, where the reference input is programmably adjustable via microcontroller 302.

[0071]Control board 155 within control module 150 is arranged to control the current through UV light module 140 and is further arranged to provide the on/off protocol of plurality of UV LEDs 141 of UV light module 140 based whether approximately 200 fpm, or greater, of air is flowing through an HVAC duct. The on/off protocol is primarily conducted via microcontroller 302 which is determined by calculating approximate airflow from communicated temperature readings from NTC thermistor and resistor 314 (heat-source temperature sensor and external heat source) and NTC thermistor 315 (ambient temperature sensor). In a preferred embodiment the on/off protocol of microcontroller 302 is arranged to turn on plurality of UV LEDs 141 of UV light module 140 when approximately 200 fpm, or greater, airflow is detected and is arranged to off plurality of UV LEDs 141 of UV light module 140 when approximately 175 fpm, or less, airflow is detected.

[0072]Negative temperature coefficient (NTC) thermistor and resistor 314 and NTC thermistor 315 are both arranged on sensor board 301. Sensor board 301 is connected to control board 155 via 4-pin connectors 323 and 322, specifically 4-pin connector is connected to ADC x2 326 of microcontroller 302. 4-pin connectors 323 and 322 also connect NTC thermistor and resistor 314 and NTC thermistor 315 to control board 155. NTC thermistor and resistor 314 are arranged such that the resistor will be used as the heat source in which NTC thermistor will measure the heat emitted therefrom. NTC thermistor 315 is arranged to measure the ambient temperature which measurements are thereby communicated to microcontroller 302 for comparison. By comparing the ambient temperature reading of NTC thermistor 315 and the temperature reading of NTC thermistor and resistor 314, microcontroller 302 can decide as to whether airflow is present and thereby initiate the on/off protocol, e.g., when the temperature readings of 314 and 315 are closer, airflow is present and when the temperature readings of 314 and 315 are farther apart, airflow is not present.

[0073]UV light module 140 includes PCB board 142, having plurality of UV LEDs 141 arranged thereon and connected thereto. Control board 155 is connected to PCB board 142 via 18-pin connectors 320 and 321, respectively. This arrangement allows PCB board 142 to be easily replaced in the event it is damaged. 18-pin connector 320 is arranged to be connected to adjustable boost converter 304, input ADC x12 324 (analog-to-digital converter) of microcontroller 302, and I2C 311 (inter-integrated circuit) of microcontroller 302, thereby connecting the aforementioned components to UV light module 140. PCB board 142 includes PCB MCU 317 which includes ADC 319 and I2C 318. Specifically, I2C 318 is connected to 18-pin connector 321, 18-pin connector 321 is connected to 18-pin connector 320, and 18-pin connector 320 is connected to microcontroller 302 at I2C 311—connecting microcontroller 302 to PCB MCU 317 for communication relay. PCB board 142 also includes NTC thermistor 316 that is arranged to provide microcontroller 302 with temperature readings of PCB board 142 and/or plurality of LEDs 141 for safety shutoff purposes.

[0074]ADC x3 325 (analog-to-digital converter with three inputs) of microcontroller 302 has three inputs that arranged to monitor values for the fault-logging protocol of microcontroller 302. The three inputs from ADC x3 325 are +24V SENSE, VLED+SENSE, and IOUT. The first input, +24V SENSE is arranged to monitor power supply 300, specifically the main power coming from power supply 300 into control board 155. In a preferred embodiment, a target range of power is programmed into microcontroller 302 and if the +24V SENSE input of ADC x3 325 detects incoming power that is not within the target range, microcontroller 302 will log the detection and determine based on the detected range whether to shut of plurality of LEDs 141. The second input, VLED+SENSE is arranged to monitor the output provided by adjustable boost converter 304. Boost converter 304 is arranged to have a preselected output, such that if VLED+SENSE detects an output different than the preselected output, microcontroller 302 may be programmed to turn off plurality of LEDs 141 and/or trigger an alarm through indicator 312 and/or alarm 313. The third input, IOUT is arranged to monitor the total current through plurality of LEDs 141. In a preferred embodiment, a target range of current is programmed into microcontroller 302 and if IOUT input of ADC x3 325 detects current through plurality of LEDs 141 that is not within the target range, microcontroller 302 will log the detection and determine which of the VRTN1-12 signals is out of the range and shut that individual LED string off.

[0075]FIG. 9 is a cross-sectional view of the present invention taken generally along line 2B-2B in FIG. 2A specifically showing air flow pathways through HVAC duct 200 with UV-C air scoop apparatus 100 installed therein. Incoming airflow IA comes from inlet end 214 of HVAC duct 200. Incoming airflow IA is treated by ultraviolet light UV emitted from UV-C air scoop apparatus 100. Ultraviolet light UV emitted from UV-C air scoop apparatus 100 treats incoming airflow IA prior to reaching UV-C air scoop apparatus 100. Once incoming airflow IA reaches inlet end 110a of UV-C air scoop apparatus 100, it is bifurcated B into upper flow UF and lower flow LF. As discussed supra, UV-C air scoop apparatus 100 includes mounting portion 113a, contoured portion 113b, and outlet portion 113c of air directing portion 113. Upper flow UF of incoming airflow IA, that has been treated by ultraviolet light UV, does two things, a portion of incoming airflow IA enters mounting portion 113a, contoured portion 113b, and outlet portion 113c of air directing portion 113, which directs the treated incoming airflow IA over heat sink 130 to assist in the heat mitigation of UV-C air scoop apparatus 100, while the other portion of incoming air IA passes directly through the lower fins of heat sink 130—also assisting in the heat mitigation of UV-C air scoop apparatus 100. Upper treated airflow UTA and lower treated airflow LTA will both continue to flow through duct 200 towards outlet end 215.

[0076]FIG. 10 is high-level flow diagram of the on/off protocol of UV-C air scoop apparatus 100. External VAC power source 300a sends VAC current to power source 300. Power source 300 converts/rectifies the VAC current to VDC current which powers UV-C air scoop apparatus 100 and provides power to all of control module 150 (shown providing power to control board 155). FIG. 10 illustrates UV light module 140 and PCB MCU 317 receiving VDC from control board 155. The heater drive is sent from control board 155 to NTC thermistor and resistor 314, specifically to resistor 314a. Resistor 314a generates heat H1 which is detected by NTC thermistor 314b to be communicated from NTC thermistor and resistor 314 to control board 155. NTC thermistor 315 detects heat/airflow temperature H2 from incoming air from the HVAC system. NTC thermistor 315 communicates the temperature reading of H2 to control board 155. Control board 155 measures the differential between NTC thermistor 315 and NTC thermistor and resistor 314 to determine if airflow is present in the HVAC duct, i.e., smaller differential equates to airflow and larger differential equates to no airflow. PCB MCU 317 also cross-communicates with control board 155 any fault condition that is either from UV light module 140 or control module 150, which fault is stored in the memory of the microcontroller of control module 150.

Fault Monitoring

[0077]The following description should be taken in view of FIG. 8 and relates to the fault monitoring recorded by microcontroller 302 or PCB MCU 317, or both.

[0078]An open UV-C LED fault would occur if a single LED of plurality of LEDS 141 was to open. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0079]A shorted UV-C LED fault would occur if a single LED of plurality of LEDS 141 was to short out. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0080]An LED current fault would occur if a single LED of plurality of LEDs 141 has a current of more than a 10% deviation from the driven value for longer than approximately 100 ms. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0081]A Boost Converter fault would occur if the output of boost converter 304 is greater than approximately 24V +5%. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0082]A High Voltage Input fault would occur if the input voltage to control board 155 is greater than approximately 24V +5%. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0083]A Low Voltage Input fault would occur if the input voltage to control board 155 is less than approximately 24V −5%. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0084]An Airflow Detection fault would occur if NTC thermistor 315 (the ambient air thermometer) detects greater than approximately 85° C., or less than approximately −20° C. If this fault is detected, a signal will be sent to microcontroller 302 and the fault will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312. Airflow detection fault is also if the thermistor of NTC thermistor and resistor 314 has a temperature greater than approximately 10° C. less than the temperature detected by thermistor 315, microcontroller 302 will be communicated the fault which will be logged into the memory of microcontroller 302 and will also indicate the failure via alarm 313 and indicator 312.

[0085]An External MCU Communication fault would occur if communication between microcontroller 302 and PCB board MCU is lost. If this fault is detected, microcontroller 302 and/or PCB MCU 317 will log the fault into their respective memories while also indicating the failure via alarm 313 and indicator 312.

[0086]An LED Stick Overtemperature fault would occur if NTC thermistor 316 detects a temperature greater than approximately 60° C., in which case microcontroller 302 will turn off plurality of LEDs 141 and microcontroller 302 and/or PCB MCU 317 will log the fault into their respective memories while also indicating the failure via alarm 313 and indicator 312.

Occupancy/Activity Based Control System

[0087]Aspects of the disclosure also relate to a system and method for controlling the UV-C air scoop apparatus, more particularly, to controlling the output, intensity, etc. of the LEDs of UV-C air scoop apparatus 100.

[0088]In addition to the airflow-based control, the present disclosure describes an advanced system and method for controlling UV-C air scoop apparatus 100 by adjusting its output in response to the detected occupancy of a room or building. This optional control system provides enhanced energy efficiency and operational intelligence by ensuring that air sanitation intensity is matched to the real-time presence of people.

[0089]The fundamental principle of this control system leverages the ubiquitous nature of modern Wi-Fi enabled mobile and computing devices, such as cellular phones 500, 502, 504, laptops 506, and tablets. These devices periodically perform an active scanning process to discover nearby wireless networks 520, such as one provided by modem 522. During this process, they broadcast signals known as “probe requests.” For the purposes of this disclosure, these probe requests are referred to as “digital signals” or “cellular signals” 508, 510, 512, 514.

[0090]Referring to FIGS. 12 and 13, an exemplary air sanitizing system 400 is shown with control module 150 that includes or is operatively connected to a digital signal or cellular detection module 402. Cellular detection module 402 is specifically configured to passively listen for and detect these cellular signals within its proximity. Its primary function is to count the number of unique probe requests it detects over a given period. This count serves as a reliable, real-time proxy for estimating the number of people and their devices present in the vicinity of apparatus 100. In on aspect, cellular detection module 402 is a Wi-Fi sniffer. This sniffer can be implemented as a distinct hardware component in communication with microcontroller 302, or alternatively, as a software-based function programmed directly into the firmware of microcontroller 302 itself. A critical aspect of this design is its commitment to privacy; module 402 is programmed only to count the signals and does not track, record, or store any identifying information from the devices it detects.

[0091]It should be appreciated that while Wi-Fi probe requests are a preferred signal for detection, the scope of the disclosure is not so limited. In other embodiments, cellular detection module 402 may be configured to detect other types of digital or analog signals that indicate the presence of occupants. For example, the module could be configured to detect Bluetooth® signals, including Bluetooth® Low Energy (BLE) advertisements or discovery packets, which are also commonly broadcast by smartphones, smartwatches, and other personal electronic devices. In another embodiment, the system could utilize a Passive Infrared (PIR) sensor to detect body heat and motion within the room, thereby directly sensing human presence rather than the presence of their devices. Therefore, the term “cellular signal” as used herein is intended to encompass any detectable electronic, radio frequency (RF), or infrared emission that correlates with the presence of one or more persons in a space, allowing microcontroller 302 to estimate occupancy.

[0092]The data flow, as illustrated in the system diagram of FIG. 13, begins with cellular detection module 402 detecting the signals and communicating the count data to the central microprocessor, microcontroller 302. Microcontroller 302 is programmed with a control logic to process this information. In one embodiment, this logic is proportional. Microcontroller 302 utilizes non-volatile memory to record the maximum and minimum number of devices commonly detected over time, establishing a dynamic operational range. Using this range, it compares the current number of detected devices and proportionally adjusts the output of UV light module 140. For example, a low device count could correspond to a lower intensity or a simple on-state, while a high device count would trigger a higher intensity output from UV LEDs 141.

[0093]To allow for customization, the system is designed to be highly configurable. The non-volatile memory can store user-defined settings, including, but not limited to: a specific UV-LED output level for maximum occupancy; a specific UV-LED output level for minimum occupancy; and a connection strength threshold. The maximum and minimum output settings allow the apparatus to be precisely tuned for its specific application, such as a small office versus a large public space. The connection strength threshold provides control over the system's spatial sensitivity. A lower threshold allows the system to count all devices within a wide broadcast range, while a higher threshold restricts the count to only those devices that are very nearby, effectively allowing the user to define whether the system protects a single room or a larger zone.

[0094]This occupancy-based control can operate independently or, preferably, in conjunction with the airflow detection system controlled by sensor board 301. As shown in FIG. 13, microcontroller 302 can receive inputs from both cellular detection module 402 and temperature sensors 314, 315. A combined control strategy requires the detection of airflow via temperature differential to turn the system on, after which the occupancy data would be used to modulate the intensity of UV LEDs 141. If airflow ceases or if the device count drops to zero, microcontroller 302 would be programmed to turn UV light module 140 off, maximizing both safety and energy savings.

[0095]The overall method 600 of controlling apparatus 100 is summarized in FIG. 14. After providing the apparatus, step 605, the operation of UV light module 140 is controlled, step 610, by one or more of two primary strategies. Step 615 represents the occupancy-based method, wherein cellular signals are detected and related to a number of devices to control the UV light. Step 620 represents the airflow-based method, wherein it is determined if an ambient and heat-source temperature are within a certain number of degrees. These methods can be used as alternatives or combined for a more robust and intelligent control solution.

[0096]The control system for air sanitizing apparatus 100 is centered around a microprocessor, specifically microcontroller 302 located on control board 155 within control module 150, as shown in the circuit schematic of FIG. 8. Microcontroller 302 includes at least one sensor interface configured to receive data from different sensor arrangements. In one embodiment, this interface includes analog-to-digital converter ADC x2 326, which receives temperature data from a temperature sensing arrangement on sensor board 301. This arrangement comprises ambient temperature sensor 315 and heat-source temperature sensor 314. In another embodiment, the interface receives data from cellular detection module 402, as depicted in FIG. 13. Microcontroller 302 also includes an output interface, comprising pulse width modulated signal generators PWM 307 and PWM 309, which transmit control signals to linear current control 306 and adjustable boost converter 304, respectively, to govern the operation of UV light module 140. Microcontroller 302 is programmed to generate these control signals based on the received sensor data. It is programmed to calculate a temperature differential from the data received from sensors 314 and 315 to control the on/off state of UV light module 140, thereby responding to the presence or absence of airflow. Alternatively or additionally, it is programmed to determine a quantity of detected signals from cellular detection module 402 to control the on/off state or the intensity of UV LEDs 141, thereby responding to room occupancy. Furthermore, microcontroller 302 is programmed to monitor multiple operational parameters for fault conditions. It uses analog-to-digital converter ADC x3 325 to monitor the main power supply voltage, the boost converter output voltage, and the total current through the LEDs. It also monitors temperature data from NTC thermistor 316 on PCB 142 for overtemperature conditions. In response to detecting a fault condition, microcontroller 302 is programmed to activate a notification device, which may comprise an audio alarm 313 connected via PWM 308, a visual indicator 312 connected via PWM x3 310, or both.

[0097]It is further contemplated that while specific components are described, the control system is not limited to the exemplary hardware. For instance, microcontroller 302 could be replaced by other processing units, such as a more complex System-on-a-Chip (SoC), an Application-Specific Integrated Circuit (ASIC), or a Field-Programmable Gate Array (FPGA) capable of handling more sophisticated tasks. Communication between control board 155 and other components like PCB 142 could utilize alternative protocols such as SPI or wireless communication standards. In a further embodiment, the control logic executed by microcontroller 302 could be enhanced with an artificial intelligence or machine learning model. Such a model could be trained over time using historical data from cellular detection module 402 and the temperature sensor arrangement to learn and predict occupancy patterns within a building. This would allow the system to proactively adjust the intensity of UV light module 140 in anticipation of scheduled meetings or peak business hours, rather than reacting to them. This AI model could also enable predictive maintenance by analyzing trends in the fault data to signal potential component failures before they occur. The execution of such a model would be performed by a suitably configured processor interfaced with the system's software and hardware modules.

[0098]The occupancy-based control system is further distinguished by its inherent adaptability and configurability. As contemplated, microcontroller 302 is configured to store user-defined operational parameters in a non-volatile memory. These parameters allow for the precise tuning of the apparatus to its specific use case. For example, a user can set distinct UV-LED output levels for both maximum and minimum detected occupancy, enabling the system to be optimized for a low-traffic private office or a high-traffic public space. A particularly advantageous configurable parameter is the connection strength threshold associated with cellular detection module 402. By adjusting this threshold, a user can effectively define the spatial sensitivity of the detection, allowing the system to respond only to devices in the immediate vicinity (e.g., a single room) or to devices across a much wider area. This feature allows the zone of sanitation to be precisely matched to the intended coverage area. The system establishes its proportional control logic by first learning or recording the typical maximum and minimum number of devices commonly detected in its installed environment, creating a calibrated baseline that makes its response both intelligent and environmentally specific.

[0099]Thus, it is seen that the objects of the present disclosure are efficiently obtained, although modifications and changes to the described aspects should be readily apparent to those having ordinary skill in the art, which modifications are intended to be within the spirit and scope of the appending claims. It also is understood that the foregoing description is illustrative of the various aspects of the disclosure and should not be considered as limiting. Therefore, other embodiments of the these aspects are possible without departing from the spirit and scope of the present disclosure.

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