Patent Description:
The fight against Covid <NUM> coronavirus is a major challenge for humanity today, from the point of view of both health and economy. People are dying, human destinies are being ruined by its devastating negative effects on health and the economy. Therefore, any solution, idea, or invention can be vital in any field of art that can prevent the spread of the virus and the infections, and can promote effective control at both individual and societal levels.

Various solutions for air sterilizers are known in the art. Such a device is described, for example, in the patent application <CIT>. Said document discloses, inter alia, an air purification device that sprays water through a nozzle onto a metal sheet. The voltage applied to the nozzle and thus to the water attracts the contaminants in the air, so they bind to the water and follow it as it flows into a collecting basin, which then transports the contaminated water to the sewer system of the building.

Another solution is to use germicidal lamps that emit UV radiation, which emit UV radiation in the wavelength range of <NUM>-<NUM>, which is effective in killing airborne bacteria and viruses.

Other solutions include fan-operated air purifiers, which purify the air by various filters and thus filters out pathogens and viruses.

Other solutions also include the heat sterilizers (chambers) used in healthcare to sterilize medical devices.

Further solutions are the photocatalytic air purifiers, which produce hydroxyl radicals and free radicals and thus destroy viruses and other pathogens in the air.

Another solution is disclosed in the document <CIT>, which thermally decomposes odours and odour components generated during the treatment of food waste, animal husbandry, composting and fermentation of agricultural waste by means of heat, wherein the air flow is provided by a fan, the heated air is cooled to a temperature that complies with environmental regulations by means of a heat exchanger. The equipment is designed for industrial use.

The disadvantage of the above described solutions is that the voltage-treated water spray does not attract viruses from the air and the device is difficult to mobilize, and its installation requires the existence of a water supply system and sewerage system.

The disadvantage of the germicidal lamps that emit UV radiation is that their radiation is dangerous to humans, animals and plants, so it should only be used when there are no living things nearby. Its reaction time is slow, several minutes of irradiation is required to kill the viruses.

A serious disadvantage of the fan-type air purifiers with filters is that they do not destroy the airborne pathogens and viruses, but collect them in their filters, so they remain active and infectious, and thereby during their operation, infectious foci may form in the filters with which we are in a common airspace. It is only a matter of time before their filter system saturates with virus and re-infects the cleaned air. Therefore, the filters need to be replaced frequently, which is a significant cost. Another disadvantage is that improper replacement and storage of filters can easily cause serious infection.

The disadvantage of the heat sterilizers (chambers) is that the infected tools must be treated with hot dry air at a temperature of <NUM>-<NUM> for <NUM>-<NUM> minutes. These devices are not suitable for immediate control of airborne viruses. Because of their design, neither are they suitable for exchanging air and disinfecting it.

The disadvantage of the photocatalytic air purifiers is that they use hydroxyl (HO) free radicals to purify the air, which are highly reactive aggressive molecules, and the free radicals in the air can be inhaled directly during operation. It is well known that free radicals are also largely responsible for the aging of the human body. It is advisable to keep contact with them to a minimum. Another disadvantage is that the prices of these devices are very high.

The disadvantage of the deodorizing device disclosed in <CIT> is that its structural design, the design, the layout and the operation concept of the heating system of its heat exchanger have been developed for industrial use for the purpose of neutralizing the odours releasing at fermenting and composting decomposing food waste, waste from animal husbandry and agricultural waste, as well as the odours from wastewater treatment, and it does not provide adequate protection against airborne pathogens, especially viruses.

The document <CIT> discloses a spiral plate heating disinfector that includes a spiral plate, a heater and a blower. The heater is fixed in the center of the spiral plate, and the spiral plate has air inlet channel and air outlet channel on two sides. The end point of the air inlet channel and the initial point of the air outlet channel are set in the center of the spiral plate, and the initial point of the air outlet channel has opening for the blower and the air inlet port to be fixed.

The document <CIT> relates to an indoor air heating and sterilizing apparatus for killing pathogenic bacteria, a virus or the like floating in a room by sucking air in the room of the hospital or the like to heat the same by a heater. The apparatus is formed so as to heat the indoor air to <NUM> or higher through a heat exchanger and the heater and has an air storage part for holding the heated air with a temperature of <NUM> or higher for about <NUM>-<NUM> sec.

The document <CIT> discloses an air sterilizer, in particular to a high-enthalpy heat island guided air sterilizer, which comprises a high-enthalpy heat island and at least one atmospheric heat exchanger, wherein the atmospheric heat exchanger is connected with the high-enthalpy heat island. The high-enthalpy heat island is positioned between the low-temperature side air outlet and the high-temperature side air inlet of the atmospheric heat exchanger.

The document <CIT> relates to a screw plate type ultra-temperature bacterium-killing machine composed of a feed pump, a shell, insulation materials, a thermometer, a pressure meter, a heat exchanger, charging/discharging pipelines, a pipe joint, a valve, etc. The heat exchanger is composed of two types of spiral plate heat exchanger. The first type spiral plate type heat exchanger has double functions of preheating liquid to be sterilized and cooling liquid sterilized. The second type spiral plate type heat exchanger has the function of instantaneous ultrahigh temperature sterilizing.

The document <CIT> discloses a combustion type heat disinfection and sterilization device. The device comprises a binary vortices shaped channel, wherein one channel is an air inlet channel with an air inlet arranged at the outer end, the other channel is divided into an inner part and an outer part from a plug, the inner part is a discharge flue with a burner interface arranged at an internal end, and the outer part is an exhaust air channel. A smoke outlet is arranged at the position adjacent to the plug in the discharge flue. An air outlet is arranged at the outer end of the exhaust air channel.

The aim of the solution according to the invention was to provide an antiviral air exchange apparatus based on new innovative solutions responding to the recent challenges, and which eliminates the above-mentioned problems and shortcomings, offers a complex solution for the protection against coronavirus and other viruses, and which, in daily use in the immediate vicinity of humans and living things, can be used continuously in practice, without harming or endangering their health.

The invention is based on the idea that the air sucked in by the apparatus, infected with coronavirus or other viruses, is sterilized in a reaction chamber centrally located inside a spiral plate heat exchanger of the apparatus in such a way that the air having a temperature in the range of <NUM>-<NUM> within the reaction chamber immediately destroys the viruses. The sterilized hot air, which has been cooled back (approximately to the intake air temperature), is then blown back into the environment so that there is a side cover on each side of the spiral plate heat exchanger, which side covers provide flow communication between the air outlet and the air inlet arranged on the same side of the apparatus. Thus, the sides of the spiral plate heat exchanger are also continuously cooled, and the heated air generated there is returned to the spiral plate heat exchanger system. Thanks to this solution, favourable energy-saving operation is achieved, and despite the high internal operating temperature (<NUM>-<NUM>), the external parts and covers of the apparatus do not heat up, which is of key importance for practical applicability. With the continuous use of the device, virus-free, healthy air is delivered into the treated room, the microenvironment and the overall environment.

The objects are achieved by providing an air sterilizer which comprises the features of claim <NUM>.

The air sterilizer according to the invention will now be described in more detail with reference to the accompanying drawings.

In the figures, the same elements are denoted by the same reference numerals in each case.

<FIG> shows a perspective view of an embodiment of the air sterilizer according to the invention from the right side. The air sterilizer comprises a housing <NUM>. At one end of the housing <NUM> there is an air supply unit <NUM>, in which a fan <NUM> is arranged in a fixed manner, which provides a flow of air in the apparatus. The fan <NUM> is protected from mechanical damage by a protective grille <NUM> located in the air supply unit <NUM> and ensures the inflow of air by the fan <NUM>. The direction of the incoming air is indicated by an arrow in <FIG>. On the air supply unit <NUM> control electronics <NUM> are arranged, to which the electrical wires <NUM> are connected. The housing <NUM> of the apparatus is sealed from the side by an end cover <NUM>. A heat-insulated side cover <NUM> is attached to the end cover <NUM> in a fixed manner (e.g. by welding). It is fixed to the side cover.

<NUM> by means of a cap <NUM> and its fixing screws <NUM>. At the other end of the housing <NUM> of the apparatus an air outlet unit <NUM> is provided, which comprises an air filter <NUM>. The air filter <NUM> is secured by a protective grille <NUM> that protects it from mechanical damage. The direction of the outgoing air is indicated by an arrow in <FIG>. The housing <NUM> of the apparatus preferably has a carrier tab <NUM> and feet <NUM> which ensure the stability of the apparatus during operation. The electrical wires <NUM> provide electric power to the apparatus. The other electrical line <NUM> provides electric power to the electric heater <NUM>.

<FIG> shows a perspective view, from the left side, of the embodiment of the air sterilizer according to the invention shown in <FIG>. The electric line <NUM> supplies electric power to the electric heater <NUM> and connects the temperature sensor <NUM> to the control electronics <NUM>. The fan <NUM> is protected from mechanical damage by a protective grille <NUM> located in the air supply unit <NUM> and ensures the inflow of air sucked in by the fan <NUM>.

<FIG> shows a schematic side view of an embodiment of an air sterilizer according to the invention, with the direction of air flow during operation, wherein the spiral plate heat exchanger <NUM> is shown within the housing <NUM> from the left side. The spiral plate heat exchanger <NUM> has an air inlet duct <NUM> running from the air inlet unit <NUM> to the electric heater <NUM> and a counterflow air outlet duct <NUM> running from the electric heater unit <NUM> to the air outlet unit <NUM>, said ducts <NUM>, <NUM> running helically next to each other. The electric heating unit <NUM> is located within a reinforced internal unit <NUM> (so-called reaction chamber) of the spiral plate heat exchanger <NUM>. The direction of air flow is indicated by arrows. The air flow is moved by a fan <NUM> located in the air inlet unit <NUM> at one end of the housing <NUM> of the apparatus.

As shown in <FIG>, the air enters the air inlet unit <NUM>, passes through the air inlet duct <NUM> to the electric heating unit <NUM> arranged in the center of the apparatus, then flows outwards through the air outlet duct <NUM> in the direction indicated by the arrows, and finally the air flows out of the air outlet unit <NUM>.

<FIG> shows an embodiment of an air sterilizer according to the invention in a schematic side view with the air flow direction during operation in a temperature range below <NUM>. The housing <NUM> of the apparatus comprises the spiral plate heat exchanger <NUM>, in the center of which the electric heating unit <NUM> is located. At one end of the housing <NUM> of the apparatus, a fan <NUM> is located in the air supply unit <NUM> in a fixed manner, which ensures the flow of air within the apparatus. The air flowing in through the air inlet unit <NUM> and then flowing through the spiral plate heat exchanger <NUM> exits from the apparatus through the air outlet unit <NUM>. In <FIG>, the air flow directions are indicated by arrows. The embodiment shown in the figure is based on an external ambient temperature of <NUM>. The electric heating unit <NUM> heats the air moved in and out by the spiral plate heat exchanger <NUM> arranged within the reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> to an operating temperature of <NUM>. <FIG> shows the approximate temperature distribution of the air flowing within the spiral plate heat exchanger <NUM>. The temperature of the exhaust air blown out of the appliance is always higher than the temperature of the air sucked in by the fan <NUM>. This is an important feature because it prevents the condensation of vapour from the air flowing in the air outlet duct <NUM> of the spiral plate heat exchanger <NUM> running from the electric heating unit <NUM> and in the air outlet unit <NUM>.

<FIG> shows a schematic side view of an embodiment of the air sterilizer according to the invention. The spiral plate heat exchanger <NUM> is arranged in the housing <NUM> of the apparatus, wherein spacer pins <NUM> provide an even distance between the adjacent plates of the spiral plate heat exchanger <NUM>. In this embodiment, the plates of the spiral plate heat exchanger <NUM> are bent from flat plates, and the spacer pins <NUM> of uniform height are permanently fixed (for example by welding) to one or both sides of the plates.

At the center of the housing <NUM> is the electric heating unit <NUM>, which is surrounded by the reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM>, the temperature of which is between <NUM> and <NUM> during operation. At one end of the housing <NUM> of the apparatus, a fan <NUM> is arranged in the air inlet unit <NUM> in a fixed manner, which ensures the flow of air. Air enters the air inlet unit <NUM> and the air sucked in by the fan <NUM> exits the air outlet unit <NUM>. The respective air outlets <NUM> are in flow communication with the air inlet units <NUM> on both sides of the fan <NUM>, so that during operation the fan <NUM> not only blows air into the air inlet duct <NUM> of the spiral plate heat exchanger <NUM> but also blows air through the air outlets <NUM> on both sides of the apparatus. The air blown out of the air outlet <NUM> is returned to the air inlet <NUM>, as it will be described in detail later.

<FIG> is a schematic unfolded perspective view of the spiral plate heat exchanger <NUM> of the air sterilizer according to the invention with the spacer pins <NUM>. The spacer pins <NUM> provide an even gap between the plates of the spiral plate heat exchanger <NUM> in the air ducts and also have a heat exchanger role due to their thermal conductivity as they are typically made of metal.

<FIG> shows a perspective view of an embodiment of the air sterilizer according to the invention, without an end cover and a side cover on the right side. In the housing <NUM> of the apparatus there is a spiral plate heat exchanger <NUM>, in the center of which there is an electric heating unit <NUM>, which is surrounded by a reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM>, wherein during operation, the temperature is between <NUM>-<NUM>. At one end of the housing <NUM> of the apparatus there is an air supply unit <NUM> with a fan <NUM> arranged in a fixed manner, which ensures the flow of air in the apparatus. The fan <NUM> is protected from mechanical damage by a protective grille <NUM>. At the other end of the housing <NUM> of the apparatus are the air outlet unit <NUM> and the other protective grille <NUM>. One of the two air outlets <NUM> is located on the side of the housing <NUM> of the apparatus.

<FIG> shows a perspective view, from the right side, of the electric heating unit <NUM> of the air sterilizer according to the invention and the inner reinforced unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM>, wherein electrical wires <NUM> providing electric power to the electric heater <NUM> are connected to the electric connection terminals <NUM> of the electric heater <NUM> by screws. The reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> surrounds the electric heating unit <NUM> and directs the incoming air and the outgoing air. The reinforced inner unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> ensures an even distribution of the heat energy (<NUM>-<NUM>) produced by the electric heating unit <NUM>, as well as the heat-resistant durability of the inner unit of the spiral plate heat exchanger <NUM>. For higher performance, several electric heating units <NUM> can be used, which can preferably be arranged next to one another, in parallel or in a triangular or circular arrangement within the reinforced inner unit.

<FIG> shows a perspective view, from the left side, of the embodiment of the air sterilizer according to the invention shown in <FIG>, without the end cover <NUM> and the heat-insulated side cover <NUM>.

<FIG> shows a perspective view, from the left side, of an electric heating unit <NUM> of the air sterilizer according to the invention and an internal reinforced unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM>.

<FIG> shows a perspective view, from the right side, of an embodiment of the air sterilizer according to the invention with the end cover <NUM>, without the side covers. The side of the apparatus and the spiral plate heat exchanger <NUM> arranged therein are sealed on both sides by a respective end cover <NUM>. An air inlet <NUM> is formed on each of the end covers <NUM> and is positioned to open into the air inlet duct <NUM> leading to the electric heating unit <NUM>. A guide hole <NUM> for the electric heater <NUM> is further formed in the end cover <NUM>, in which one end of the electric heater <NUM> is located. There is an air outlet <NUM> on each side of the housing <NUM> of the apparatus. It should be noted that although not shown in the drawings, the air inlet ducts <NUM> and the air outlet ducts <NUM> of the spiral plate heat exchanger <NUM> are also hermetically sealed from each other by the end cover <NUM>.

<FIG> shows a perspective view, from the left side, of an embodiment of the air sterilizer according to the invention with the end cover <NUM> and without side covers. A guide hole <NUM> is also formed in the left-side end cover <NUM> for the electric heater <NUM>, in which the other end of the electric heater <NUM> is accommodated. In addition, a guide hole <NUM> is formed in the left-side end cover <NUM> for the temperature sensor <NUM> in which the temperature sensor <NUM> is located.

<FIG> shows a perspective view, from the right side, of an embodiment of the air sterilizer according to the invention, with the end cover <NUM> and with exploded parts during operation of the apparatus, also indicating the air flow directions. The side of the housing <NUM> and the open sides of the spiral plate heat exchanger <NUM> are hermetically sealed by the end cover <NUM> on which the air inlet <NUM> is formed. When the fan <NUM> is operating, the air flows into the air inlet unit <NUM> and a part of the air continues to flow into the spiral plate heat exchanger <NUM> into its air inlet duct <NUM> as shown in <FIG>, then flowing out from the electric heating unit <NUM> through the air outlet duct <NUM> and exits into the environment through it. When the fan <NUM> is operated, the air sucked in by the apparatus also exits the air outlets <NUM> formed on both sides of the housing <NUM> and flows through the chamber <NUM> formed between the end cover <NUM> and the heat-insulated side cover <NUM> and returns to the air inlet <NUM> through the two lateral air inlets <NUM>. The purpose of this external ventilation is to provide air cooling, by means of ambient air, for the end cover <NUM> that becomes hot during operation. The air flowing through the chamber <NUM> also keeps the temperature of the outer side cover <NUM> relatively low, so that it cannot cause burns. Its further purpose is to return the heat energy generated on the sides of the spiral plate heat exchanger <NUM>, thus also on the side covers <NUM>, back to the system of the spiral plate heat exchanger <NUM>.

<FIG> shows a perspective view, from the left side, of an embodiment of the air sterilizer according to the invention with the end cover <NUM>, with exploded parts, also showing the direction of air flow during operation of the apparatus. A temperature sensor <NUM> is located in the guide hole <NUM> formed in the end cover <NUM>, which extends into the space of the chamber <NUM> and is connected to the electrical line <NUM> shown in <FIG>.

<FIG> shows an embodiment of an air sterilizer according to the invention, in a schematic side view, with a spiral plate heat exchanger <NUM> provided with a heat-insulating channel <NUM>, also showing the direction of the air flow during operation. In the housing <NUM> of the apparatus, the spiral plate heat exchanger <NUM> is shown in a side view, which has two counter-current channels, namely the air inlet duct <NUM> and the air outlet duct <NUM>, which channels run helically next to each other, and wherein a spiral insulating channel <NUM> is arranged between the two ducts. Arrows indicate the direction of air flow, which is moved by a fan <NUM> located in an air inlet unit <NUM> located at one end of the housing <NUM> of the apparatus. As it can be seen in the drawings, the air enters the air inlet unit <NUM>, travels along the path indicated by the arrows in the counter-current duct of the spiral plate heat exchanger <NUM> and flows out from the air outlet unit <NUM>. The purpose of the heat insulating channel <NUM> is to reduce or prevent the transfer of heat from the inside to the outside perpendicular to the ducts. The heat insulating channel <NUM> is preferably a duct with a hollow interior, preferably filled with rock wool and hermetically sealed from its outer environment and from the air outlet duct <NUM> and the air inlet duct <NUM>.

<FIG> shows a perspective view, from the left side, of an embodiment of the air sterilizer according to the invention, without the end cover <NUM> and the heat-insulated side cover <NUM>.

<FIG> and the enlarged <FIG> show a perspective view, from the left side, of a longer electric heating unit <NUM> of the air sterilizer according to the invention and an embodiment of the internal reinforced unit <NUM> (reaction chamber) of a spiral plate heat exchanger <NUM> according to the invention, wherein the <NUM> electrical wires which provide the electric power supply are connected to the connection terminals by screws. The reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> surrounds the electric heating unit <NUM> and directs the air flowing inside the apparatus in the desired direction around the electric heating unit <NUM>. The reinforced inner unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> ensures an even distribution of the heat (<NUM>-<NUM>) produced by the electric heating unit <NUM> and also provides heat-resistant durability for the inner unit <NUM> of the spiral plate heat exchanger <NUM>. This embodiment is essentially the same as the embodiment shown in <FIG>, except that a longer electric heating unit <NUM> is used, the role of which is described in the following figures.

<FIG> shows a perspective view, from the left side, of an embodiment of the air sterilizer according to the invention, without the end cover <NUM> and the heat-insulated side cover <NUM>. In the housing <NUM> of the apparatus there is a spiral plate heat exchanger <NUM> provided with a spiral thermal insulation channel <NUM>, in the center of which there is an electric heating unit <NUM> which is longer than the embodiment shown in <FIG>. At the end portion of this heating unit <NUM>, a plurality of heat releasing elements, for example the heat sinks shown in the drawings, are arranged. The purpose of the heat sinks <NUM> is to return the heat generated at the ends of the heating unit <NUM> and at the end cover <NUM>, and thus also the heat flow, through the air inlet <NUM> up to the air inlet duct <NUM> running towards the heating unit <NUM>. Thus, the lateral outward heat flow can be significantly reduced and heat loss through the side covers <NUM> can be minimized.

<FIG> shows a perspective view, from the left side, of the heat sinks <NUM> and the inner reinforced unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> located at the ends of the longer electric heating unit <NUM> of the air sterilizer according to the invention.

<FIG> shows a perspective view, from the right side, of an embodiment of the air sterilizer according to the invention, with the end cover <NUM>, without the heat-insulated side cover <NUM>. The side of the housing <NUM> of the apparatus and the sides of the heat insulating channel <NUM> and the spiral plate heat exchanger <NUM> accommodating therein are hermetically sealed by the end cover <NUM> on which the air inlet <NUM> is formed on both sides of the apparatus, said air inlets <NUM> always opening into the air inlet duct <NUM> running towards the electric heating unit <NUM>. The guide hole <NUM> of the electric heater <NUM> is also formed on the end cover <NUM>. In this guide hole <NUM> one end of a longer electric heater <NUM> is located, at the end of which heat sinks <NUM> are arranged. The two air outlets <NUM> are located on both sides of the housing <NUM> of the apparatus. At one end of the housing <NUM> of the apparatus there is an air supply unit <NUM> with a fan <NUM> arranged in a fixed manner, which ensures the flow of air in the apparatus and which is protected from mechanical damage by the protective grille <NUM>. At the other end of the housing <NUM> of the apparatus are the air outlet unit <NUM> and the other protective grille <NUM>. It should be noted that although it is not shown in the drawings, the side of the heat insulating channel <NUM> and the channels of the spiral plate heat exchanger <NUM> are also sealed laterally by the end cover <NUM>.

<FIG> shows a perspective view, from the left side, of an embodiment of the air sterilizer according to the invention, with the end cover <NUM>, without the heat-insulated side cover <NUM>. As shown in the figure, the guide hole <NUM> of the temperature sensor <NUM> is also guided through the heat sinks <NUM>.

<FIG> shows a perspective view, from the right side, of an embodiment of the air sterilizer according to the invention, with the end cover <NUM> and with exploded parts, and showing the air flow directions during operation of the apparatus. The guide hole <NUM> of the electric heater <NUM> is further formed on the end cover <NUM>, in which one end of an electric heater <NUM> of greater length is located, at the end of which the heat sinks <NUM> are arranged. In this embodiment, the depth of the thermally insulated side covers <NUM> is greater in order to accommodate the heat sinks <NUM> in the chamber <NUM>. The dimensions of the chamber <NUM> are determined by the internal sizes of the side covers <NUM>.

<FIG> shows a perspective view, from the left side, of an embodiment of the air sterilizer according to the invention, with the end cover <NUM> and with exploded parts, also showing the air flow directions during operation of the apparatus.

As described above, the apparatus according to the invention uses a spiral plate heat exchanger <NUM> which applies air cooling on both sides and wherein the heat-generating electric heating unit <NUM> can be accommodated in the inner central part of the spiral plate heat exchanger <NUM>.

The purpose of the electric heating unit <NUM> is to heat the air flowing in the spiral plate heat exchanger <NUM> and its internal unit <NUM> (reaction chamber) to a temperature of <NUM>-<NUM>, whereby the viruses in the incoming air are immediately destroyed by the high temperature. During operation of the apparatus, the air flowing in the reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> and in the central part of the spiral plate heat exchanger <NUM> has approximately a constant operating temperature along a section of at least <NUM>-<NUM>, so the viruses in the air are subject to the heat for longer time to achieve perfect virus removal. If, for example, a fan <NUM> with a power of <NUM> Watts is used, the air flow rate in the innermost section of the ducts <NUM>, <NUM> of the spiral plate heat exchanger <NUM> is ca. <NUM>/s, as a result of which the viruses and other pathogens transported by the air flowing within the apparatus remain in the innermost section of at least <NUM> of the ducts <NUM>, <NUM> for ca. <NUM> second, which is sufficient at said temperature to kill almost <NUM>% of the viruses and other pathogens. (The prescribed operating parameters for indoor heat sterilization in healthcare are: <NUM> minutes at <NUM>, <NUM> minutes at <NUM>, <NUM> minutes at <NUM> to ensure complete sterility of medical devices. Based on these data, a temperature of <NUM> is required for <NUM> second to achieve complete sterility). Reference:
https://semmelweis. hu/nepegeszsegtan/files/<NUM>/<NUM>/1819_II_AOKgy02_Sterilizálás. pdf <FIG> shows the temperature distribution inside the apparatus at an operating temperature of <NUM>. Due to the design of the apparatus, the resulting high temperature inside the apparatus is concentrated in the reinforced internal unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM>, which is important because the heat generated therein can better managed, there is enough space and time to cool it back efficiently in a way that the generated heat energy is returned into the system through the spiral plate heat exchanger <NUM> and reused.

In addition to the air sterilization, another practical aspect is the practical applicability of the apparatus. One of the basic conditions for this is that the outer covers of the apparatus do not become too hot during operation. To this end, the heat must be kept inside the apparatus, which can be used again in the thermal energy system of the apparatus. With the right dimensioning and design, perfect air sterilization and outstanding energy-saving operation can be achieved and the outer covers of the apparatus do not heat up. The air inlet duct <NUM> running from the air supply unit <NUM> to the electric heater unit <NUM> and the counterflow air outlet duct <NUM> running from the electric heater unit <NUM> to the air outlet unit <NUM> run helically next to each other so that the incoming air can receive the heat energy of the outgoing air without getting into contact with each other, thus allowing the outgoing air to cool back sufficiently. However, the sides of the spiral plate heat exchanger <NUM>, especially around the sides of the reinforced inner unit <NUM> (reaction chamber) of the spiral plate heat exchanger <NUM> and at the ends of the electric heater <NUM>, have very high temperature during operation, so double-sided air cooling is of key importance from the point of view of practical applicability.

The fan <NUM> is preferably a radial fan, such as the radial fan TS400 SIROCO of SIROCO CLEYENS NP GROUP. The spacer pins <NUM> provide an even gap between the plates of the spiral plate heat exchanger <NUM> during its manufacture and thereafter in order to maintain a corresponding even gap, and the spacer pins <NUM> also have a role of heat exchange due to their thermal conductivity.

For an even more sophisticated operation of the apparatus, the spiral plate heat exchanger <NUM> (<FIG>) is provided with a heat-insulating channel <NUM> in order to reduce or prevent the outward heat flow perpendicular to the ducts. Furthermore, a longer electric heater <NUM> is provided at the ends of electric heaters <NUM> (<FIG>). In this case, in the chamber <NUM>, the heat sinks <NUM> dissipate the generated heat from the ends of the electric heating unit <NUM> and provide laminar air flow and heat dissipation for the double-sided air cooling, which provides an outstanding thermal insulation effect on the sides of the apparatus. Additionally, the heat sinks <NUM> also direct the generated heat energy into the air inlet duct <NUM> through the air inlets <NUM> arranged on both sides of the apparatus. Using this technology, premium quality energy consumption can be achieved in the apparatus without outer covers' heating up.

The control electronics <NUM> allows to regulate the internal operating temperature by means of the temperature sensor <NUM>. The housing <NUM> of the apparatus is preferably provided with <NUM> carrying tabs for moving the apparatus and feet <NUM> for stable placement.

The apparatus is preferably designed to be capable of operating at both <NUM>-<NUM> V DC and <NUM>-<NUM> V AC.

Upon demand, the apparatus may be equipped with a pollen filter, which can be placed in the air outlet unit <NUM>, which is fixed by the protective grille <NUM>, and filters out the virus-free air flowing out so that patients suffering from allergy can also use it without risk.

Furthermore, the apparatus can also be used for room heating by reducing the power of the spiral plate heat exchangers <NUM>, while the sterilization of the intake air remains unchanged. Instead of the control electronics <NUM>, a simple bimetallic thermal switch can be used to regulate the internal temperature, and instead of the temperature sensor <NUM>, a bimetallic thermometer can be built in to measure the internal temperature.

The specific embodiments described herein are only for illustrative purposes, and it will be apparent to those skilled in the art how the embodiments shown may be modified or combined with one another to provide additional embodiments within the scope of the invention.

The air sterilizer according to the invention can be used continuously in the immediate environment of humans and living beings without risking their health. The apparatus sucks in the air infected with coronavirus from its surroundings and then immediately destroys the Covid <NUM> coronavirus contained in the intake air inside the reaction chamber at a temperature of <NUM>-<NUM>. It blows the cleaned hot air back into its environment by cooling it down (approximately to the temperature of the intake air). The apparatus has been developed for everyday home use, therefore it is structurally designed so that despite its high internal operating temperature, its external components and covers do not warm up and the temperature of the cleaned air blown out is almost the same as the temperature of the intake air. By using the apparatus continuously, virus-free healthy air can be provided in a room or in the environment.

The antiviral air sterilization apparatus according to the invention can be preferably used in particular in areas where several persons are present in a closed space and the concentration of viruses in the air is therefore increased. Such areas in healthcare include hospitals, corridors and waiting areas, as well as aircraft cabins, airports, ambulances, taxis, public transport, other closed-space passenger transport tools (e.g. elevators, cable cars, etc.). It can also be used in law enforcement organizations, shops, theatres, homes, and any area where there is a risk of virus infection.

The apparatus according to the invention can also be used effectively in agriculture and animal husbandry, since trans-infections from various viruses and bacteria (e.g. avian influenza, swine fever, sterilization) are a serious problem for animals kept indoors, which can cause amazing damage to livestock. The apparatus can be used to drastically reduce or eliminate trans-infections and to effectively localize infections.

Claim 1:
An air sterilizer comprising
- a housing (<NUM>) having, at one end thereof, an air supply unit (<NUM>) in which a fan (<NUM>) is arranged in a fixed manner,
- a spiral plate heat exchanger (<NUM>) arranged in the housing (<NUM>) and comprising an electric heating unit (<NUM>) in its central part,
- an air outlet unit (<NUM>) at the other end of the housing (<NUM>),
- wherein the spiral plate heat exchanger (<NUM>) has an air inlet duct (<NUM>) running from the air inlet unit (<NUM>) to the electric heater (<NUM>) and a counterflow air outlet duct (<NUM>) running from the electric heater (<NUM>) to the air outlet unit (<NUM>), which ducts (<NUM>, <NUM>) run helically next to each other,
- each side of the spiral plate heat exchanger (<NUM>) is sealed by an end cover (<NUM>),
- in the spiral plate heat exchanger (<NUM>) there is a constant distance between the adjacent plates of the air inlet duct (<NUM>) and the air outlet duct (<NUM>);
characterized in that
- an air outlet (<NUM>) is formed at one end of the housing (<NUM>), adjacent to the air supply unit (<NUM>), on each side of the housing (<NUM>),
- an air inlet (<NUM>) is formed on the end covers (<NUM>), which opens into the air inlet duct (<NUM>) running to the electric heating unit (<NUM>),
- a guide hole (<NUM>) is formed in the end cover (<NUM>) for a temperature sensor, in which a temperature sensor (<NUM>) is accommodated,
- on the end covers (<NUM>) there is a heat-insulated side cover (<NUM>) on both sides of the air sterilizer, said side covers (<NUM>) being sealed to the housing (<NUM>) and defining a chamber (<NUM>) which establishes flow communication between the air outlet (<NUM>) and the air inlet (<NUM>) on the same side of the air sterilizer.