Indoor air purifier, room with indoor air purifier and method for purifing air inside a room

Abstract

An air purifier (1) for purifying indoor air and a method are disclosed. The housing (10) of the air purifier is divided into a mixing subspace (14), a filter subspace (15), a moving subspace (16), a further filter subspace (17) and an exit subspace (18). The air purifier allows the outside air (4) and the room air (6) to be cleaned to be mixed. At least one soda lime filter (24) and Lithium hydroxide filter (27) of the filter device (21) is provided in the filter subspace (15) of the housing (10) in the air flow (9) and is arranged prior to the moving subspace (16).

Description

[0001] INDOOR AIR PURIFIER, ROOM WITH INDOOR AIR PURIFIER AND METHOD FOR PURIFING AIR INSIDE A ROOM

[0002] The invention relates to an air purifier for interior spaces. In particular, the air purifier comprises a housing which is closed on all sides and comprises a base wall, a ceiling wall and four side walls. The base wall defines an air inlet and the ceiling wall defines an air outlet. A fan is provided in the housing of the air purifier and generates an air flow in the housing, which is directed from the base wall to the ceiling wall. A filter device is also provided in the housing, through which the generated air flow passes. A pre-filter of the filter device is located opposite the floor wall and the room air drawn in flows through the pre-filter.

[0003] The invention also relates to a method for purifying the air inside a closed room using an air purifier.

[0004] The German utility model DE 21 2021 000 541.1 discloses an air purification device used for air purification in rooms. The air purification device has an outer body and an air inlet on the outer body, which ensures that the polluted air in the environment is drawn in at a certain height above the floor. Inside the air purifier, after the fan, there is a filter cell comprising an F8 pre-filter, an activated carbon filter and a HEPA filter.

[0005] The German utility model DE 202020 107 386 U1 relates to an air purification device with a housing, an air inlet through the base and an air outlet. The flow path leads through a filter device. A pre-filter, an activated carbon filter and a fine filter are provided in the blower. Downstream of the fan is a HEPA filter, which filters out any germs from the raw air flowing in from the air inlet.

[0006] The German utility model DE 20 2020 105 929 U1 relates to an air purification device for installation in a room, comprising a fan for generating an air flow. An odour filter and a fan are located between the air inlet and the air outlet. A particle filter (HEPA high- performance filter) is provided above the fan.

[0007] The German utility model DE 20 2020 105 204 U1 relates to an air purification device for purifying room air. A fan is used to draw in the room air to be purified through intake openings. A plurality of filter devices, such as a pre-filter, fine dust pre-filter, high- performance filter (heatable), activated carbon filter and post-filter mat, are provided in the housing of the air purification device. A neutralization device with a heating element is used to neutralize pathogens. The German patent application DE 10 2014 012 870 A1 relates to an air purifier in which the housing has an air inlet and an air outlet. A fan is arranged adjacent to the air inlet. A UV LED unit and a filter unit are arranged above the fan along a flow path of the air. The filter unit comprises a photocatalytic filter and a collecting filter for bacteria.

[0008] The US patent application US 2008 / 019861 A1 relates to an air treatment device with a fan for stimulating the air flow through the air treatment device and a UV treatment chamber with a UV radiation source for killing microorganisms in the air flow. A HEPA filter and an activated carbon filter are arranged along the air flow.

[0009] The US patent application US 2022 / 373203 A1 relates to an air sterilization device with a heating device. The air sterilization device with heater is aimed at the secondary inactivation of viruses by high temperatures. After the sterilization and disinfection processes have been completed by a UV sterilization device and a heating system, the purified air is returned to the room.

[0010] US patent application US 2023 / 0120319 A1 relates to a method for sterilizing an inner surface of an air purifier or a filter medium. For this purpose, the inner surface or the filter medium is exposed to an ion cloud.

[0011] DE 20 2021 101 555 U1 discloses a device for filtering air. The device comprises a housing enclosing an interior space with an air inlet cross-section and an air outlet crosssection. The device is defined by a pre-filter stage, a main filter stage and an air conveying device. The air conveying device defines a clean air space, wherein surfaces are coated with an antimicrobial effective substance, especially one that inactivates viruses.

[0012] GB 513699 A discloses a ventilation system so that impurities such as toxic gases are removed from air which is drawn by a fan through an inlet duct and passed through several filters. If required, the air also passes through an ozonizer prior to entering the enclosure.

[0013] CN 207035334 U discloses fresh air purifying all -in -one machine. The structure of the machine includes the circulating fan, purification module and the anion generator that establish ties in proper order in the wind channel. The purification module includes an activated carbon layer and photocatalyst layer, wherein the photocatalyst layer's top is provided with an UV light source, a HEPA purify layer and an activated carbon layer.

[0014] CN 204923254 U discloses an air purifier machine. The air inlet chamber is provided with left air intake and right air intake. None of the above-mentioned documents disclose the purification of air in a room, which is a mixture of air drawn from the room itself and outside air (air from the environment, outside from the room). In addition, conventional air purifiers do not remove CO2 from the room air. Most air purifiers, as can be seen from the cited state of the art, use HEPA filters and activated carbon filters. HEPA filters remove particles. Activated carbon filters remove some gas pollutants. None of the conventional air purifiers can remove CO2 from indoor air.

[0015] The object of the invention is to provide an air purifier for indoor spaces that enables user- friendly improvement of indoor air quality by purification of the indoor air from particles, bacteria and viruses while at the same time maintaining human well-being indoors. Additionally, the air purifier should be able to adjust its purification capabilities with respect to the level of pollution.

[0016] This problem is solved by an air purifier for interior spaces, which comprises the features of claim 1 .

[0017] A further object of the invention is to provide a method for purifying indoor air which enables user-friendly purification of the indoor air from particles, bacteria and viruses while maintaining human well-being indoors and adjusts its purification capabilities with respect to the actual pollution.

[0018] According to one possible embodiment of the invention, a housing for the indoor air purifier is closed on all sides and consists of a bottom wall, a ceiling wall and four side walls. The bottom wall defines an air inlet. The ceiling wall defines an air outlet. A fan is provided in a moving subspace and generates an air flow inside the housing. Once the air purifier is turned-on the fan starts to rotate and thereby pulling contaminated air from the room to be treated through at least one prefilter located on the base wall of air purifier. The negative pressure generated by the fan in the moving subspace initiates an air flow which is directed from the base wall to the ceiling wall, wherein a filter device with at least one prefilter is positioned on the base wall, so that sucked-in room air moves through the at least one prefilter of the filter device and enters a mixing subspace. A supply duct with a controllable fan, wherein the controllable fan draws in outside air via the supply duct into the mixing subspace. The contaminated air from the room mixes with the air coming from outside the room. At least one UVC radiation source is housed in the moving subspace. An exit subspace of the housing defines air outlet in the ceiling wall of the air purifier, wherein at least one heating element is provided in the exit subspace. The advantage of the air purifier according to the invention is that at least the CO2 content of the room air to be purified is reduced from the air flow moved through the air purifier and at least bacteria and viruses are eliminated to maintaining human well-being indoors.

[0019] According to a further advantageous embodiment the air purifier is provided at least with one further heating element is in the mixing subspace of the purifier. The advantage is that the air inside of the air purifier can be held at a certain temperature level, regardless of the air temperature coming from the outside.

[0020] According to a further embodiment at least one HEPA filter is provided in a further filter subspace of the housing. The further filter subspace is arranged upstream of the moving subspace (and below the exit subspace. The further filter subspace has the advantage that a final fine filtration stage takes place, which is accomplished when the air inside the housing passes through at least one HEPA filter.

[0021] According to a further embodiment of the invention, the control and regulation unit is assigned to the air purifier. The control and regulation can be part of the air purifier or can be embodied as a separate unit. The control and regulation unit receives data from at least one sensor device and sends control signals to at least one operating element of the air purifier.

[0022] The sensor devices comprise at least one room sensor, at least one thermal sensor, at least one audio sensor, at least one particle sensor and / or at least one CO2 - sensor. It is understood by a person skilled in the art that the above list of sensor types is not to be understood as a restriction. The sensor elements may also contain sensor types not listed or combinations thereof. At least one audio sensor detects and recognizes cough and other breathing noises coming from the inside of the treated room. The type, amplitude and frequency of cough is analyzed, and action is taken in real-time to adjust the purification mode and the intensity of filtration so that air is purified in accordance with the type and intensity of the cough detected in the treated area.

[0023] The data from the sensor elements are processed and analyzed by the control and regulation unit. Control and regulation signals are sent to operating elements of the air purifier. The operating elements comprise, for example a controllable fan in the supply duct, an automatic speed controller for the fan in the moving subspace, at least one heating element in the exit subspace, at least one further heating element in the mixing subspace and the UVC radiation source in the moving subspace. A display is arranged on a side wall of the air purifier and is communicatively connected to the air purifier's control and regulation unit. The display informs the user about the quality of the air coming out of the air purifier, the number of operating hours, the speed of the fan and / or the temperature or humidity of the purified air. Warnings, if present, can also be displayed.

[0024] A filter subspace is arranged in the air flow after the mixing subspace. A filter device of the filter subspace, which is, in the direction of the air flow, prior to the moving subspace, is composed at least of a soda lime filter and an activated carbon filter. Additionally, the filter device of the filter subspace comprises a lithium hydroxide filter. In the direction of the air flow the activated carbon filter, the soda lime filter and the lithium hydroxide filter are positioned in the filter device.

[0025] Due to the negative pressure generated by the fan in the mixing subspace, the mixed air passes through filter device of the filter subspace, which is composed of multiple stage filters. The multiple stage filter consists of an activated carbon filter, a soda lime filter and a lithium hydroxide filter. The multiple stage filter will reduce CO2 present in the incoming air. It also removes harmful gases, odor and unpleasant smell from the air flow in the housing.

[0026] The control and regulation unit communicates with the numerous sensors in the air purifier, controls and regulates the operation of the air purifier. The control and regulation unit can be used, for example, to switch the UVC radiation source on and off or increase the intensity of the UVC radiation source. The speed of the air flow entering the device can also be controlled by the rotation speed of the fan in the moving subspace. This means that the volume of air to be cleaned can be controlled.

[0027] The method according to the invention for purifying the air of a closed room with an air purifier is characterized by several steps: When the air purifier is turned on, the fan in the moving subspace of the air purifier is operated, the room air is sucked in through a bottom wall of the air purifier and an air flow passes through a prefilter into the mixing subspace. Outside air can be fed into the air flow that has passed through the pre-filter via a supply duct and the controlled rotation of a controllable fan in supply duct. The room air and the outside air are mixed within the mixing subspace.

[0028] In the meantime, data are sent from at least one sensor device to a control and regulation unit associated with the air purifier. The control and regulation unit analyzes the sent data at least partly with artificial intelligence. The control and regulation unit sends control signals to at least one operating element of the air purifier in real-time. The control signals are sent to the fan in the mixing subspace so that by adjusting the rotation rate and the power of the fan in the moving subspace, the mixture of the air (outside air and room air) in the mixing subspace is controlled. Additionally, the decontamination of the air flow within the moving subspace is controlled by adjustment of the power and / or the intensity of at least one UVC radiation source. Moreover, heating the air flow in the mixing subspace and / or an exit subspace is initiated, if the temperature of the air flow is below a predefined set value.

[0029] According to the inventive method the sensor devices comprise at least one room sensor, at least one thermal sensor, at least one audio sensor, at least one CO2 - sensor and / or at least a particle sensor. The at least one audio sensor is suitable to recognize at least cough, but can also be used to recognize breathing, snoring, sneezing or general sounds of increased activity inside and other noises inside of the treated room.

[0030] The operating elements being implemented in the air purifier comprises a controllable fan in the supply duct, an automatic speed controller for the fan in the moving subspace, at least one heating element in the exit subspace, at least one further heating element in the mixing subspace and the UVC radiation source in the moving subspace. The intensity of the UVC radiation source is controlled by the result of the analysis of the amplitude and / or frequency of at least the cough by control and regulation unit of the air purifier.

[0031] One aspect of the present invention related to the automatic control of an air purifier. The automatic control is based for example on acoustic signals, in particular the detection of coughing inside the room where the air purifier is placed. The control according to different types of cough is not implemented for the time being, as this increases the technical complexity of operating an air purifier. According to one aspect of the invention, the indoor air quality is improved by automatically activating the air purifier as soon as at least one audio sensor detects a cough, which indicates a potentially increased concentration of particles, bacteria and / or viruses in the air inside the room.

[0032] State of the art air purifiers usually operate continuously or must be activated manually, which often leads to inefficient energy consumption. In addition, such air purifiers do not react immediately to sudden air pollution, which are caused by coughing or similar noises. The air purifier has at least one audio sensor associated which can be a microphone. The at least one microphone can be associated to a signal processor and a control regulation unit of the air purifier. The signal processor can be part of the control and regulation unit.

[0033] The microphone picks up sounds from the environment (inside the room). It is calibrated to be particularly sensitive to frequency ranges associated with coughing (typically between 500 Hz and 2,500 Hz). The acoustic signal processor analyzes the sounds picked up by the microphone and compares them to a stored acoustic pattern for coughing. This is done using a pattern recognition algorithm based on machine learning. As soon as the system identifies a sound as a cough, the processor sends a signal to the control and regulation unit. The control and regulation unit receives the signal from the acoustic signal processor and then activates the air purifier. The number of cough events detected influences the operating time and the number of revolutions of the fan in the moving subspace of the air purifier takes. This enables an adaptive control of the cleaning intensity of the air purifier regarding pollution bay bacteria and / or viruses.

[0034] The mode of operation of the air purifier can take place in two ways. Firstly, when a person coughs near the air purifier, the sound is picked up by the audio sensor (microphone). The acoustic signal processor analyzes the sound and compares it with the stored cough patterns. As soon as a cough is detected, the air purifier is automatically activated.

[0035] Secondly, the air purifier can switch to a higher operating level to clean the air quickly and efficiently form the pollution caused by coughing.

[0036] The advantage of the activation or the increased level of operation of the air purifier immediately after a cough is detected reduces the spread of pathogens and particles in the air inside the room. This feature allows the control of the overall energy consumption of the air purifier, because the elements of the air purifier are turned on only if needed.

[0037] In alternative embodiment, the air purifier could also detect with the at least one audio sensor other breathing sounds such as sneezing or general sounds of increased activity. In addition, the air purifier could be integrated into existing smart home technologies to enable comprehensive and connected control of indoor air quality.

[0038] In certain environments, the outside temperature (the temperature of the air outside the treated room) is extremely low. When the air purifier is turned on, the air coming from outside (for example drawn in through the supply duct) is extremely cold compared to the temperature of the treated room. When the outdoor and indoor air mix takes place in the mixing subspace of the air purifier, the overall temperature drops before it is treated and released back into the room. This creates an unpleasant environment in the treated room. To solve this problem, a thermostatically controlled heating element is added to the mixing subspace where the two air streams are brought together. A sensor is located in the mixing subspace of the air purifier to measure the temperature and the control and regulating unit of the air purifier operated the heating element on demand. Additionally, when the temperature of the air exiting exit subspace is below a certain set temperature, the heating element is switched on to reduce the gap between the outside and inside temperatures and create a more comfortable environment.

[0039] The process according to the invention can be monitored and executed by means of the control and regulation unit. The air purifier can be programmed and controlled via a mobile application (such as an APP).

[0040] A soda-lime filter consists of a mixture of sodium hydroxide (NaOH) and calcium oxide (CaO), which is provided in the indoor air purifier according to the invention in the form of a flat filter element. The purpose of a soda lime filter is to reduce or remove carbon dioxide (CO2) from the room air.

[0041] An activated carbon filter filters pollutants such as chlorine, heavy metals, dyes, hormone and drug residues, PFCs (polyfluorinated chemicals), organic hydrocarbons, microplastics, pesticides, herbicides, fungicides, bacteria, germs and odour and taste-disrupting substances from water or air.

[0042] A HEPA filter is the measure of all things when the mechanical cleaning of air is required. The abbreviation HEPA stands for "High Efficiency Particulate Air". In essence, the translation of the term HEPA filter roughly means "air filter with high efficiency against particles". HEPA filters are made of cellulose, glass fibers or other synthetic materials. The initially very thin filter layers are stacked in several layers to maximize the filter area in the smallest possible space. Depending on the material used, a HEPA filter can be washed out and reused.

[0043] UVC light is used in the fight against bacteria and viruses. UVC light is generally capable of damaging the genetic material of microorganisms and viruses. However, the radiation dose must be high enough and the irradiation time long enough. Air can be effectively disinfected by UVC light.

[0044] The invention and its advantages are described in more detail below with reference to the accompanying schematic drawings.

[0045] Figure 1 shows a schematic representation of the arrangement of an air purifier in a room that is closed off from the outside.

[0046] Figure 2 shows a schematic representation of a possible embodiment of the invention for supplying outside air.

[0047] Figure 3 shows a perspective view of a housing of the air purifier. Figure 4 shows a sectional view of a possible embodiment of the internal structure of the air purifier along the sectional line A-A from Fig. 3.

[0048] Figure 5 shows a schematic and enlarged view of the second compartment of the air purifier.

[0049] Figure 6 shows a schematic and enlarged view of the third compartment of the air purifier.

[0050] Figure 7 shows a schematic and enlarged view of an embodiment of the fifth compartment of the air purifier.

[0051] Figure 8 shows a schematic and enlarged view of a further possible embodiment of the fifth compartment of the air purifier.

[0052] Figure 9 shows a schematic frontal view of the respiratory limescale filter.

[0053] Figure 10 shows a schematic design of the ceiling wall of the air purifier.

[0054] Figure 11 shows a sectional view of a further embodiment of the internal structure of the air purifier.

[0055] Figure 12 is a partly cut away view of the air purifier, showing the set-up of the filter device in the filter subspace if the embodiment shown on Fig. 11 .

[0056] Figure 13 shows a view onto a side wall of the air purifier, equipped with sensors and a control element of a control and regulation unit.

[0057] Figure 14 shows a flow diagram of a method for purifying air inside a room using the inventive air purifier.

[0058] In the following, examples of embodiments will explain the invention and its advantages in more detail with reference to the attached figures. The proportions in the figures do not always correspond to the actual proportions, since some shapes are simplified, and other shapes are shown enlarged in relation to other elements for better visualization.

[0059] Figure 1 shows a schematic representation of the arrangement of an air purifier 1 in a room 2 that is closed off by wall elements 60 to the outside. The air purifier 1 is provided with a supply duct 3, which is designed, for example, as a flexible hose, a rigid pipe, etc. Outside air 4 can be supplied to the air purifier 1 from outside room 2 via the supply duct 3. The outside air 4 and room air 6 drawn in by the air purifier 1 are mixed in the air purifier 1 and purified accordingly. Furthermore, at least one sensor device 33, which is for example a room sensor 31 , can be provided in room 2, which determines, for example, the CO2 content, the temperature and / or the particle content of the room air 6. These data are transmitted to a control and regulation unit 30 (see Fig. 4) of the air purifier 1 to control the purification of the room air 6, the supply of outside air 4 and various other operating elements of the air purifier 1 .

[0060] Figure 2 shows a schematic representation of a possible embodiment of the arrangement of the supply duct 3 of outside air 4 to the air purifier 1. According to the embodiment shown here, the supply duct 3 can be designed as a flexible hose that leads from the air purifier 1 through a window 81 to the outside air 4. To reach the outside air 4 with the supply duct 3 a window kit 82 is part of window 81. The flexible hose transports the outside air 4 to the air purifier 1 and mixes it in the mixing subspace 14 with the room air 6 drawn by a fan 20 (see Fig. 4) into the air purifier 1 .

[0061] Figure 3 shows a perspective view of housing 10 of the air purifier 1 . The housing 10 comprises a base wall 11 , a ceiling wall 12 and four side walls 13. According to the embodiment shown here, housing 10 can be provided with caster wheels 19 in order to position the housing 10 inside the room 2 in a simple and easy manner. One of the side walls 13 can, for example, be designed as a door to allow access to the interior of the air purifier 1 .

[0062] A display 34, which is in communication with a control and regulation unit 30 (see Fig. 4), is located in one of the side walls 13. Preferably, display 34 is integrated in the front side wall 13. The display 34 shows for example the quality of the air coming out of the air purifier 1 , the number of operating hours, temperature / humidity, the speed of the fan 20 (see Fig. 4) and, if necessary, symbols indicating warnings.

[0063] According to a possible embodiment of the invention, a window 35 can also be part in one of the side walls 13. Via window 35 it is possible to check visually the condition of the soda lime filter 24 (see Fig. 4).

[0064] Figure 4 shows a sectional view of a possible embodiment of the internal structure of the air purifier 1 along the sectional line A-A in Fig. 3. The housing 10 can be divided into several subspaces14, 15, 16, 17 and 18. In the embodiment shown here, the housing 10 is subdivided into a filter subspace 15, a mixing subspace 14, a moving subspace 16, a further filter subspace 17 and an exit subspace 18. It is self-evident to a person skilled in the art that the illustration of the embodiment of the housing 10 (shown in Fig. 4) with the subspaces 14, 15, 16, 17 and 18 is not intended to be understood as a limitation of the invention. According to the embodiment shown in Fig. 4, the filter subspace 15 is defined by the base wall 11 followed by a filter device 21 . The filter device 21 is defined, according ti the embodiment shown here by a particle filter 29 and a pre-filter 22. An air flow 9 is generated inside the housing 10 by a fan 20, with which the room air 6 is drawn through the filter subspace 15 into the mixing subspace 14 via at least one air inlet 5 in the base wall 11 . The room air 6 passes through the at least one prefilter 22 of the filter subspace 15 and enters via the generated air flow 9 the mixing subspace 14.

[0065] Outside air 4 is supplied to the mixing subspace 14 via a supply duct 3. For this purpose, the supply duct 3 ends in one of the side walls 13 (see Fig. 2) of the housing 10. The supplied outside air 4 and the room air 6, which has passed through the at least one prefilter 22 of the filter device 21 , are mixed in the mixing subspace 14.

[0066] The fan 20, which generates the air flow 9 in the housing 10 and conveys the air (mixed air) to be cleaned through the housing 10, is provided in the moving subspace 16.

[0067] The moving subspace 16 of the housing 10 is followed by the further filter subspacel 7, in which at least a HEPA filter 23 of the filter device 21 is provided. At least one UVC radiation source 25 is part of the moving subspace 16. The air flow 9 of the mixed air is moved by the fan 20 in the moving subspace 16 and is subjected to UVC radiation of an UVC radiation source 25 in the moving subspace 16. Then the air flow 9 enters a further filter subspace 17, which encompasses another filter device 21 . The other filter device 21 is composed of a HEPA filter 23. According to the embodiment shown in Fig. 4 an activated carbon filter 26 is provided in filter subspace 17.

[0068] The filter subspace 17 of the housing 10 is followed by the exit subspace 18, into which the cleaned air enters and from there, the purified air is fed back into room 2 via the air outlet 7.

[0069] A control and regulation unit 30 can be positioned inside the housing 10 of the air purifier 1 . The control and regulation unit 30 is responsible for the adjustment of the of various parameters (like temperature of the air entering the air purifier 1 , temperature of the air exiting the air purifier 1 , power of the fan 20, power for the controllable fan 36 in the supply duct 3, receiving data from various sensor devices 33 related to the air purifier 1 ) in order to achieve an effective cleaning of the air returned into the room 2. The various sensor devices 33 can be for example at least a room sensor 31 , a CO2 sensor, a thermal sensor 37 or an audio sensor 41 . Subspace 15 is defined by the base wall 11 followed by a filter device, which comprises a prefilter 22 only.

[0070] Subspace 14 compromises air mixing chamber for room air 5 and outside air 4. A Further heating element 52 (thermal heated) is also located in subspace 14.

[0071] Figure 5 shows a schematic and enlarged view of the mixing subspace 14 of the air purifier 1 according to the embodiment shown in Fig. 4. As mentioned in the description of Fig. 4, outside air 4 enters the mixing subspace 14 via the supply duct 3, which may be a flexible hose, for example. The outside air 4 is mixed with the air that has entered the mixing subspace 14 through the prefilter 22 (see Fig. 4) of the filter subspace 15. At least one sensor device 33 is provided in mixing subspace 14. The sensor device 33 can be for example, a CO2 sensor 47, a thermal sensor 37 and / or a particle sensor 48. The data from the sensor devices 33 can be used, for example, by the control and regulation unit 30 (see Fig. 6) to control at least one operating element which is, for example, the fan 36 in the supply duct 3 in order to draw in outside air 4, the fan 20 in the moving subspace 16 or the further heating element 52 in the mixing subspace 14.

[0072] The sensor device 33 can be for example, a CO2 sensor 47, a thermal sensor 37 and / or a particle sensor 48. These sensors can be located in the various subspaces 14, 16 (see Fig. 6), 18 (see Fig. 7).

[0073] Figure 6 shows a schematic and enlarged view of moving subspace 16 of the air purifier 1 . In addition to the fan 20, the control and regulation unit 30 can also be accommodated in the moving subspace 16. The fan 20 in the moving subspace 16 is used to generate and maintain the air flow 9 through the air purifier 1. The air flow 9 in moving subspace 16 passes as well the UVC radiation source 25 in the moving subspace 16.

[0074] The control and regulation unit 30 is used, for example, to switch on and off the UVC radiation source 25 in the moving subspace 16 (see Fig. 4). Switching on and off can also be carried out via a timer. The output temperature of the air purifier 1 can also be set by means of a heating element 32 (see Fig. 7). This is particularly advantageous in cold areas. Controlling the speed of the air flow 9 through the air purifier 1 and controlling the air speed at which the room air 6 enters the air purifier 1 is also possible using the control and regulation unit 30.

[0075] Figure 7 shows a schematic and enlarged view of a possible embodiment of the exit subspace 18 of the air purifier 1 . The air flow 9 enters the exit subspace 18 of the air purifier 1 via a respiratory limescale filter 24. In the embodiment shown here, a heating element 32 is provided in the exit subspace 18. Likewise, at least one sensor 33 is installed in the fifth subspace 18. As already mentioned, the at least one sensor 33 can determine the CO2 content and / or the particles in the air mixture and / or the temperature of the air flow 9 in the exit subspace 18.

[0076] Figure 8 shows a schematic and enlarged view of a further possible embodiment of the exit subspace 18 of the air purifier 1 . Here, an activated carbon filter 26 is provided above the respiratory limescale filter 18 in the filter subspace 15. According to the embodiment shown here an activated carbon filter 26 and a soda lime filter 24 are placed in the filter subspace 15. The air flow 9 enters exit subspace 18 via the soda lime filter 24 followed by the activated carbon filter 26.

[0077] Figure 9 shows a schematic front view of the respiratory soda lime filter 24. For this purpose, the respiratory soda lime filter 24 can have at least one transparent section 35. By means of the transparent section 35, the user of the air purifier 1 determines when the respiratory soda lime filter 24 needs to be replaced. According to a possible embodiment of the invention, a window 35 can be formed in a side wall 13 of the air purifier 1 , which is aligned with the transparent section 35 of the respiratory soda lime filter 24. Thus, the user does not need to open the side wall 13 of the air purifier 1 to replace the limescale filter 24. A discoloration can be used to indicate whether the limescale filter 24 is used up. The limescale filter 24 can sit in a frame 40 to stabilize the limescale filter 24 and make it easier to handle.

[0078] Figure 10 shows a schematic design of the ceiling wall 12 of the air purifier 1. Several openings 50 are formed in the ceiling wall 12, through which the purified air flow 9 exits the air purifier 1 . The base wall 11 has a similar design. The unpurified room air 6 enters the air purifier 1 through the floor wall 11 .

[0079] Figure 11 shows a sectional view of a further embodiment of the air purifier 1 . One side wall is removed in order to show the internal set-up of the air purifier 1 according to the embodiment shown here. Once the air purifier 1 is turned on the fan 20 in the moving subspace 16 of the air purifier 1 is turned on. The fan 20 starts to rotate and thereby pulling contaminated air through an air inlet 5 from room 2 to be treated through a filter device 21 , which at least comprises a prefilter 22. Filter device 21 and consequently the prefilter 22 are located on the floor wall 11 of the air purifier 1 . The fan 20 initiates an air flow 9 inside housing 10 which reaches from the floor wall 11 to the ceiling wall 12 of the air purifier 1 . A controllable fan 36 is assigned to the supply duct 3. A supply duct filter 28 is part of the supply duct 3 and positioned, in the embodiment shown here, prior to the controllable fan 36. The supply duct 3 reaches through a wall (or window 81 , see Fig. 2) element 60 and when the controllable fan 36 rotates, outside air 4 (fresh air from the outdoors) is drawn through the supply duct 3 into the mixing subspace 14 of the air purifier 1.

[0080] The supply duct 3 is connected on one side to a wall or window kit 82 and on the other side to and to the air purifier 1 . The wall kit 82 is provided with a controllable flap 61 to prevent, for example, nesting of insects or the like during time intervals of no operation.

[0081] The fan 20 in the moving subspace 16 causes, due to the generated negative pressure, the air flow 9 within the air purifier 1 . From the mixing subspace 14 the mixed air enters filter subspace 15. The filter subspace 15 holds the filter device 21 which is composed, according to the embodiment shown in Fig, 11 , by an activated carbon filter 26, a soda lime filter 24 and a lithium hydroxide filter 27 (the activated carbon filter 26, soda lime filter 24 and lithium hydroxide filter 27are located between mixing subspace 14 and moving subspace 16). The filter device 21 is, as already mentioned, a multiple stage filter device, which reduces CO2 from the air flow 9, present in the incoming air flow 9 from the mixing subspace 14. The filter device 21 also removes odor and unpleasant smell from the air flow 9.

[0082] From filter subspace 15 the air flow 9 enters the moving subspace 16. In the moving subspace 16 a disinfection takes place with the aid of at least one UVC radiation source 25. From the moving subspace 16 the air flow 9 enters a further filter subspace 17. Here a final fine filtration takes place which is accomplished when the air flow 9 passes through a HEPA filter 23. From the further filter subspace 17 the air flow 9 enters the exit subspace 18. The exit subspace 18 houses at least one thermal sensor 37, which measures the temperature of the purified air entering form the further filter subspace 17. If the temperature is less than a temperature set by a control and regulation unit 30, a heating element 32 is turned on. The cleaned air defines an air outlet 7 which exits through the ceiling wall 12 of the air purifier 1 . According to the embodiment shown here, the control and regulation unit 30 may also have an integrated acoustic signal processor (not shown).

[0083] Figure 12 is a partly cut away view of the air purifier 1 , showing the filter device 21 in the filter subspace 15 of the embodiment of air purifier 1 as shown in Fig. 11 . The soda lime filter 24 of the filter device 21 is equipped with a transparent section 35. The transparent section 35 allows the user to determine when the respiratory soda lime scale filter 24 needs to be replaced. Figure 13 shows a view onto a side wall 13 of the air purifier 1 which is equipped with sensor devices 33 and a control element 38 of a control and regulation unit 30 (see Fig.11 ) which is partly integrated in the housing 10 of the air purifier 1 . According to the embodiment shown here, housing 10 of the air purifier 1 carries at least one room sensor 31 . It is to be understood that the least one room sensor 31 can be placed in addition in the room 2 itself.

[0084] The room sensor 31 is for example an audio sensor 41 which detects and recognizes, for example cough coming from the inside of the treated room 2 where the air purifier 1 is placed. The control and regulation unit 30 of the air purifier 1 analyses the type, amplitude and frequency of the cough. The analysis of the cough, breathing, snoring and other noises in the room takes place with artificial intelligence. According to the type, amplitude and frequency of the cough an action is taken in real-time to adjust the purification mode and the intensity of filtration of the air purifier 1 . As a result of the analysis, air is purified in accordance with the type and intensity of the cough detected inside room 2 where air purifier 1 is placed. It is clear for a person skilled in the art, that the invention is not limited to audio sensors 41 being placed on a sidewall 13 of the of the air purifier 1 , the audio sensors 41 can be placed in addition within the room 2 and communicate with the control and regulation unit 30 of the air purifier 1 .

[0085] In alternative embodiment, the air purifier 1 can also detect other breathing noises such as sneezing or general sounds of increased activity inside the room 2. The system for analyzing the type, amplitude and frequency of noise could also be integrated into existing smart home technologies to enable comprehensive and networked control of indoor air quality.

[0086] Artificial intelligence can be used to analyze the noises (for example: the type, amplitude and frequency of the cough, breathing noises (such as sneezing or snoring) or general sounds of increased activity) inside room 2. As a result of the analysis the artificial intelligence initiated the required control of the air purifier 1.

[0087] A sidewall 13 of the air purifier 1 carries a selector switch 44 for manual or automatic and a speed controller 46 for the fan 20. As shown in Fig. 11 - 13 the air purifier 1 is placed on castor wheels 19, so that the air purifier 1 can be easily moved within the room 2 to different locations. The dashed lines indicate the various subspaces 14, 15, 16, 17 and 18 (see Fig. 4 or Fig. 11 ) of air purifier 1 according to and embodiment of the invention.

[0088] Figure 14 shows a flow diagram of a method for purifying air inside a room 2 using the inventive air purifier 1 . Once the air purifier 1 is turned-on the fan 20 in the moving subspace 16 of the housing 10 starts to rotate. The rotation of the fan 20 pulls contaminated air from room 2 the air purifier 1 is placed in through a filter device 21 comprising at least one prefilter 22. Filter device 21 is located on floor wall 11 at the bottom of air purifier 1. The air purifier can be programmed and started via a mobile application.

[0089] Additionally, a controllable fan 36 is started as well. The controllable fan 36 withdraws outside air 4 (fresh air) from the outdoors through a supply duct 3 into the mixing subspace 14 of air purifier. The outside air 4 is passed through a supply duct filter 28 prior to entering the mixing subspace 14. The supply duct 3 is connected on one side to a window kit or wall so that outside air 4 can enter the supply duct 3. In the mixing subspace 14 room air 5 mixes with outside air 4. The percentage of mixture can be controlled by the rotation rate of the power of fan 20 and the power of controllable fan 36.

[0090] The fan 20 in the moving subspace 16 generates a negative pressure, so that an air flow 9 of mixed is generated. The mixed air passes through a filter device 21 which can comprise multiple stage filters. In the embodiment shown here the filter device 21 of a filter subspace 15 houses the filter device 21 which comprises, in the embodiment shown here, the activated carbon filter 26, the soda-lime filter 24 and the lithium hydroxide filter 27. The filter device 21 reduces CO2 present in the incoming air and also removes harmful gases, odor and unpleasant smell from the air flow 9.

[0091] Once the air flow 9 gets mixed in mixing subspace 14, the air flow 9 continues in the direction within the air purifier 1 and passes various filters. These filters comprising an activated carbon filter 26, a soda lime filter 24 and a lithium hydroxide filter 27. The filters 24, 26 and 27 are responsible for reducing CO2 present in the incoming air in addition to removing chemical pollution and unpleasant smell from the air flow 9.

[0092] The air flow 9 then passes through the moving subspace 16 in which a disinfection takes place. The disinfection is carried out with an UVC radiation source 25 in the moving subspace 16.

[0093] From the moving subspace 16 the air flow 9 reaches a further filter subspace 17 which comprises a HEPA filter 23. The HEPA filter 23 is the final fine filtration stage when air flow 9 passes through the HEPA filter 23.

[0094] Prior to the entry of the air outlet 7 into the room 2 the airflow 9 enters an exit subspace 18. At least one thermal sensor 37 is present in the exit subspace 18 for measuring the temperature of the air flow 9 (purified air) in the exit subspace 18. If the temperature is less than a set temperature, at least one heating element 32 is turned on. Finally, the air outlet 7 (purified and / or heated) exist in to room 2.

[0095] At least one audio sensor 41 (part of the air purifier 1 and / or positioned in the room 2) detects and recognizes cough coming from the inside of the room 2. The type, amplitude and / or frequency of the cough is analyzed for example by the control and regulation unit 30 of the air purifier 1 or by an external station (not shown).

[0096] Actions are taken in real-time by the air purifier 1 to adjust purification mode and intensity of filtration so that air is purified in accordance with the type and intensity of the cough detected in room 2. The actions can be for example, powering up the fan 20 in the moving subspace 16, powering up the controllable fan 36 in the supply duct 3 for outside air 4 or the intensity of the UVC radiation source 25.

[0097] It is believed that the present disclosure and many of the advantages mentioned therein will be understood from the foregoing description. It is apparent that various changes in the form, construction and arrangement of the components can be made without departing from the disclosed subject matter. The form described is merely explanatory, and it is the intent of the appended claims to encompass and include such modifications. Accordingly, the scope of the invention should be limited only by the appended claims.

[0098] List of reference symbols:

[0099] 1 Air purifier

[0100] 2 Room

[0101] 3 Supply duct

[0102] 4 Outside air

[0103] 5 Air inlet

[0104] 6 Room air

[0105] 7 Air outlet

[0106] 81 Window

[0107] 82 Window kit, wall kit

[0108] 9 Air flow

[0109] 10 Housing

[0110] 11 Floor wall

[0111] 12 Ceiling wall

[0112] 13 Side wall

[0113] 14 Mixing subspace

[0114] 15 Filter subspace

[0115] 16 Moving subspace

[0116] 17 Further filter subspace

[0117] 18 Exit subspace

[0118] 19 Caster wheel

[0119] 20 Fan

[0120] 21 Filter device

[0121] 22 Prefilter

[0122] 23 HEPA filter

[0123] 24 Soda lime filter

[0124] 25 UVC radiation source

[0125] 26 Activated carbon filter

[0126] 27 Lithium hydroxide filter

[0127] 28 supply duct filter

[0128] 29 Particle filter

[0129] 30 Control and regulation unit

[0130] 31 Room sensor

[0131] 32 Heating element

[0132] 33 Sensor device 34 Display

[0133] 35 Transparent section

[0134] 36 Controllable fan

[0135] 37 Thermal sensor

[0136] 38 control element

[0137] 39 Filter

[0138] 40 Frame

[0139] 41 Audio sensor

[0140] 42 Window

[0141] 44 Selector switch

[0142] 46 Speed controller

[0143] 47 CO2 - sensor

[0144] 48 particle

[0145] 50 Opening

[0146] 52 Further heating element

[0147] 60 Wall element

[0148] 61 Controllable flap

[0149] A Cutting line

Claims

AMENDED CLAIMS received by the International Bureau on 24 June 2025 (24.06.2025)1. An indoor air purifier (1 ), comprising a housing (10) closed on all sides and consisting of a bottom wall (11 ), a ceiling wall (12) and four side walls (13)and the ceiling wall (12) defining an air outlet (7), a fan (20) in a moving subspace (16) generates an air flow (9) inside the housing (10) from the base wall (11 ) to the ceiling wall (12); characterized by an air inlet (5) is defined by the bottom wall (11 ); a filter device (21 ) with at least one prefilter (22) is positioned on the base wall(11 ), so that sucked-in room air (6) moves through the at least one prefilter (22) of the filter device (21 ) and enters a mixing subspace (14); a supply duct (3) with a controllable fan (36), wherein the controllable fan (36) draws in outside air (4) via the supply duct (3) into the mixing subspace (14); at least one UVC radiation source (25) is housed in the moving subspace (16); and an exit subspace (18) of the housing (10) defines air outlet (7) in the ceiling wall(12) of the air purifier (1 ), wherein at least one heating element (32) is provided in the exit subspace (18) and at least one further heating element (52) is provided in the mixing subspace (14) of the purifier (1 ).

2. Air purifier (1 ) according to claim 1 , wherein at least one HEPA filter (23) is provided in a further filter subspace (17) of the housing (10) which is arranged upstream of the moving subspace (16) and below the exit subspace (18).

3. Air purifier (1 ) according to any of the preceding claims, wherein a control and regulation unit (30) is assigned to the air purifier (1 ) and the control and regulation unit (30) receives data from at least one sensor device (33) and sends control signals to at least one operating element of the air purifier (1 ).

4. Air purifier (1 ) according to claim 3, wherein the sensor devices (33) comprise at least one room sensor (31 ), at least one thermal sensor (37), at least one audio sensor (41 ), at least one particle sensor (48) and / or at least one CO2 - sensor (47).

5. Air purifier (1 ) according to claim 3, wherein the operating element comprises the controllable fan (36) in the supply duct (3), an automatic speed controller (46) for the fan (20), the at least one heating element (32) in the exit subspace (18), the at least one further heating element (52) in the mixing subspace (14) and the UVC radiation source (25) in the moving subspace (16).

6. Air purifier (1 ) according to claim 3 - 5, wherein a display (34) is arranged on a side wall (13) of the air purifier (1 ) and is communicatively connected to the air purifier's (1) control and regulation unit (30).

7. Air purifier (1 ) according to any of the preceding claims, wherein a filter subspace (15) is arranged in the air flow (9) after the mixing subspace (14) and a filter device (21 ) of the filter subspace (15) and prior to the moving subspace (16) is composed at least of a soda lime filter (24) and an activated carbon filter (26).

8. Air purifier (1 ) according to claim 7, wherein the filter device (21 ) of the filter subspace (15) comprises in addition a lithium hydroxide filter (27), wherein in the direction of the air flow (9) the activated carbon filter (26), the soda lime filter (24) and the lithium hydroxide filter (27) are positioned in the filter device (21 ).

9. A room (2) with an air purifier (1 ) according to any one of the preceding claims.

10. A method for purifying air (6) inside a closed room (2) with an air purifier (1 ), comprising the following steps:• turning on the air purifier (1 ) and thereby powering a fan (20) in a moving subspace (16) of the air purifier (1 ), wherein the speed of the fan (20) is controlled by an automatic speed controller (46) and a controllable fan (36) in the supply duct (3) which ends in a mixing subspace (14);• drawing in room air (6) by rotation of the fan (20) through a base wall (11 ) wherein an air flow (9) passes through a pre-filter (21 ) and enters the mixing subspace (14) and drawing in outside air (4) through a supply duct filter (28) by rotation of the controllable fan (36) in supply duct (3) into the mixing subspace (14);• sending data from at least one sensor device (33) to a control and regulation unit (30) associated with the air purifier (1);• analyzing the sent data in the control and regulation unit (30) with artificial intelligence and the control and regulation unit (30) sends control signals to at least one operating element of the air purifier (1 ) in real-time; and thereby o controlling a mixture of the air in the mixing subspace (14) by adjusting the rotation rate and the power of fan (20) in a moving subspace (16) and the power of fan (36) in the supply duct (3), o decontaminating the air flow (9) within the moving subspace (16) is controlled by intensity adjustment of the at least one UVC radiation source (25), and o heating by at least one further heating element (52) the air flow (9) in the mixing subspace (14) and / or heating by at least one heating element (32) the air flow (9) in an exit subspace (18) if the temperature of the air flow (9) is below a predefined value.

11. Method according to claim 10, wherein the sensor devices (33) comprise at least one room sensor (31 ), at least one thermal sensor (37), at least one audio sensor (41 ), at least one CO2 - sensor (47) and / or at least a particle sensor 48.

12. Method according to claim 11 , wherein at least one audio sensor (41 ) recognizes cough, breathing, snoring, sneezing or general sounds of increased activity inside and other noises inside of the treated room (2).

13. Method according to claim 12, wherein the intensity of the UVC radiation source (25) is controlled by the result of at least the analysis of the amplitude and / or frequency of the cough by control and regulation unit (30) of the air purifier (1 ).

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