Air cleaner

Abstract

To provide a method for sterilizing an inner surface of an air purifier or a filter medium in the air purifier.SOLUTION: A method for sterilizing an internal surface of an air purifier or a filter medium in an air purifier by exposing said internal surface or said filter medium to an ion cloud. The air purifier includes an ionizer. Preferably, the ionizer comprises a corona discharge tip and a receiving electrode. When the corona discharge tip is subjected to an appropriate voltage, the corona discharge tip generates an ion cloud between the tip and a receiving or ground electrode.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an improved air purifier. [Background technology]

[0002] U.S. Patent No. 2007034082 discloses an air purifier including an ionizing assembly that operates to charge particulate material in an airflow passing through the purifier. The charged particulate material is attracted to and retained by a filter element disposed downstream of the ionizing assembly and having an opposite charge to the charged particulate material. The purified air passing through the filter, optionally along with a fragrance added to the purified airflow, is directed outside the device. The ionizing assembly is formed with a grounding member disposed adjacent to the ionizing member to retain electrons generated by the ionizing assembly within the purifier, thereby preventing electrostatic discharges from occurring outside the purifier. The airflow is directed through the purifier in an angled, substantially laminar manner by a fan to increase the efficiency of the purifier.

[0003] U.S. Patent No. 2002141131 discloses an improved air ionizer device including an air inlet, a high-voltage source, an electrode electrically connected to the high-voltage source for generating ions, and an air outlet. An air mover is provided for directing air into the air ionizer through the air inlet and out of the air ionizer through the air outlet. A perforated filter including a conductive material is electrically coupled to at least one of the voltage source and ground. The filter is positioned over at least one of the air inlet, air outlet, and electrode so that air entering the air inlet, air exiting the air outlet, or air flowing past the electrode flows through the filter. In a preferred embodiment, the filter comprises a metal grid or screen.

[0004] WO 2018 / 058716 discloses an integrated fresh air purifier comprising a housing (1), an indoor return air inlet (21), an outdoor fresh air outlet (22), a fresh air delivery outlet (2), an indoor return air discharge outlet (12), and a power supply control device arranged within the housing (1), in which a first-stage filter (3), a heat exchange core (4), an exhaust fan (5), a second-stage filter (6), an ion cloud dust removal module, a blower (9), and a third-stage filter (10) are arranged in this order, and the exhaust fan (5), the ion cloud dust removal module, and the blower (9) are electrically connected to the power supply control device. This all-in-one device combines ventilation and air purification functions, is plug-and-play, and does not pose difficulties in installation and maintenance, or the structural problems of installing air pipes and damaging the room. It has a high negative ion generation rate, a long transport distance, and powerful dust removal and disinfection effects. Furthermore, it does not produce ozone during operation, maintaining a healthy environment.

[0005] Chinese Patent No. 105823131 discloses a combined fresh air purification system with a teaching scope. The combined fresh air purification system includes an air treatment assembly. The air treatment assembly includes a fresh air ventilation device and an air purifier. The fresh air ventilation device and the air purifier are independently arranged and fixed at different positions in a room, and can be combined to control indoor air quality. According to the combined fresh air purification system with a teaching scope, the combination of a constant oxygen air purifier and a clean fresh air ventilation device can create a constantly clean, constant oxygen, energy-saving, and green eco-friendly classroom, providing students with a safe and clean learning environment.

[0006] U.S. Patent No. 2005055990 discloses an air cleaner and a method for controlling the operation of the air cleaner. The air cleaner includes a cabinet having an inlet and an outlet, a filter assembly for removing dust and odor particles from indoor air, a fan, a sensor assembly for sensing the composition of the indoor air, a supply assembly for providing clean air with at least one deficient component of the indoor air, and a controller for controlling the supply assembly based on data regarding the composition of the indoor air. In another aspect, a method for controlling the operation of the air cleaner includes the steps of sensing indoor air, measuring the deficient component and its amount, and providing clean air with at least one deficient component of the indoor air.

[0007] Despite the existence of the prior art, there remains a need for improved air cleaners, particularly air cleaners that are more hygienic throughout their working life.

[0008] Air purifiers work by filtering ambient air through a filter. Thus, anything in the air can theoretically be captured by the filter. There are various types of filtration means, from particulate filters to gas filters, but it is an inevitable consequence of the function of an air purifier that it also captures microorganisms trapped in the air stream.

[0009] It is also common for air purifiers to have various sensors that indicate when particulates are being removed, as their primary focus is removing contaminants from the ambient air. As a result, it is also common for air purifiers to function in automatic mode, with the presence of particulates affecting the speed of airflow through the device. Therefore, when air quality is good, it is possible, and often desirable, to keep the purifier in idle or standby mode to conserve energy. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] U.S. Patent No. 2007034082 [Patent Document 2] U.S. Patent No. 2002141131 [Patent Document 3] International Publication No. 2018 / 058716 [Patent Document 4] Chinese Patent No. 105823131 [Patent Document 5] U.S. Patent No. 2005055990 Summary of the Invention [Problem to be solved by the invention]

[0011] However, if the air is not passed through purifying microorganisms that are captured by the filter, they can quickly multiply and form biofilms, which can negatively impact the lifespan of an effective filter and pose a health hazard to users accustomed to their home environment. [Means for solving the problem]

[0012] Thus, in a first aspect, there is provided a method for sterilizing an interior surface of an air cleaner or a filter media within an air cleaner by exposing said surface or said filter media to an ion cloud.

[0013] Preferably, the air purifier comprises an ionizer configured to generate an ion cloud on said interior surface or said filter media.

[0014] The air purifier includes an ionizer, preferably including a corona discharge tip and a backing electrode, which, when subjected to an appropriate voltage, generates an ion cloud between the tip and the backing or ground electrode.

[0015] The purifier may further include an ionizer disposed externally to the device. If the ionizer is disposed externally, it is preferably disposed on the top surface of the device. Locating the external ionizer on the top surface of the device means that household dust particles are more likely to agglomerate as they become ionized and therefore electrically charged as they pass through the air and fall toward the ground. As they become more agglomerated, the household dust particles are more easily caught in the air circulation pattern generated by the device and are therefore more easily filtered.

[0016] The ionizer located inside the device is preferably located in front of the removable particulate filter in the air flow direction.

[0017] Preferably, the device includes an internal ionizer and an external ionizer. The external ionizer facilitates the agglomeration of household dust particles, while the internal ionizer facilitates the capture of the agglomerated dust particles by the removable particulate filter. In both cases, ionization allows for a less dense filtration medium and lower air (fan) velocity.

[0018] The ionizer used comprises an emitter electrode and a ground electrode, and when a suitable voltage, preferably in the range of -10 to 10 kV, more preferably in the range of -8 to 8 kV, is applied to the emitter electrode, the emitter emits an ion cloud between the emitter and the receiver.

[0019] The emitter electrode is preferably a point, a tip, or a plurality of tips or points, eg, a brush, and is in electrical communication with a voltage source.

[0020] The receiving electrode is preferably a ring-shaped metal piece so that as ions are expelled away from the emitter and then drawn towards the receiver, the resulting ion cloud is three-dimensional.

[0021] Preferably, the emitter is positioned centrally between the receivers in the form of a ring. The emitter may be positioned towards or away from the airflow during use, but preferably the emitter faces the surface to be sterilized, e.g., an inner wall or filter media.

[0022] In an alternatively preferred embodiment, the ionizer is disposed on a removable filter media. In such an embodiment, the filter media includes at least an emitting electrode. The receiving electrode may be part of the purifier or part of the filter media, but in either case, the removable filter media includes a means for electrical communication with the purifier so that the ionizer can generate an ion field when the filter media is placed in a working configuration. In such an embodiment, both the purifier and the filter include electrical connectors that cooperate to conduct electricity from the purifier to both the ionizer, i.e., the emitter and receiver, disposed on the filter.

[0023] Preferably, the ionizer comprises a corona discharge tip positioned within 15 cm of the surface to be sterilized.

[0024] In a second aspect, a method is provided for sterilizing an internal surface or filter media of an air cleaner, the air cleaner comprising an ionizer, a removable particulate or gas filter, an airflow generator, means for controlling the airflow generator, a first airflow setting having an air filtered airflow rate, and a second airflow setting correlated with sterilization of the internal surface and / or removable particulate or gas filter of the air cleaner.

[0025] In a third aspect, there is provided an air purifier comprising a removable filter media, an airflow generator, and an ionizer, said purifier comprising at least one airflow setting and a further setting in which the ionizer is activated in the absence of airflow or in combination with an airflow setting such that the filter media is subjected to an airflow with a media velocity of between 0.1 and 1.2 cm / s.

[0026] The airflow velocity measured at the removable filter is known in the art as media velocity. Media velocity is the speed at which air moves through the filter. Media velocity must be perfectly controlled to ensure the maximum amount of particles is captured. If the velocity is too fast, many contaminants will go straight through without being filtered. If the velocity is too slow, the purifier will not reach the farthest corners of the room fast enough to be effective.

[0027] In a fourth aspect, an air purifier is provided that includes a removable filter media, an airflow generator and ionizer, a temperature sensor, and a humidity sensor. The inventors have surprisingly found that the air draft required to kill microorganisms is significantly lower than the air draft required for air filtration. Furthermore, the inventors have found that subjecting a surface to the air draft and then the ionizer, or vice versa, also improves sterilization properties.

[0028] Preferably, the air cleaner includes a removable filter media, which may be a particulate filter or a gas filter.

[0029] Preferably, the airflow velocity (media velocity) measured at the removable filter is at least 0.1 cm / s as measured at the filter media. Measurements at the filter media are taken from the spatial center point on the fan side of the filter media surface. If multiple filter media are present, the surface taken for air draft measurement is the one closest to the airflow generator and therefore first to receive the air draft.

[0030] More preferably, the airflow velocity measured at the removable filter is between 0.1 and 1.2 cm / s. Most preferably, the airflow velocity measured at the removable filter is between 0.2 and 1.1 cm / s.

[0031] Preferably, when in the sterilization mode, the airflow generator generates an airflow consistent with sterilization of the interior surfaces and / or filter media of the air purifier for a period of 1 second to 10 hours. Similarly, when in the sterilization mode, the air purifier generates an ion cloud for a period of 1 second to 10 hours in the absence of airflow or in the presence of only low air velocities, such as measured at the filter media of 0.1 to 1.2 cm / s.

[0032] Preferably, ionization (A) and low-velocity airflow (0.1-1.2 cm / s, (B)) are performed exclusively, more preferably sequentially. This means that the surface to be sterilized is first subjected to an air draft, and then, when the air draft is stopped, the surface is exposed to a burst of ionization. Similarly, ionization may be performed before the air draft.

[0033] It is also preferred that the sequence of air draft followed by ionization, or vice versa, be repeated so that the surface to be sterilized is intermittently subjected to both air draft and ionization.

[0034] Preferably, (A) has a duration of 1 minute to 10 hours.

[0035] Preferably, (B) has a duration of 1 minute to 10 hours.

[0036] In a preferred embodiment, an air purifier is provided that includes a removable particulate or gas filter, an airflow generator, means for controlling said airflow generator, a first airflow setting having an air filtered airflow velocity, a second airflow setting that correlates with sterilization of an internal surface of the air purifier and / or the removable particulate or gas filter, and an ionizer.

[0037] Preferably, the air purifier includes a mode operable to sterilize internal surfaces or filter media, whereby an air draft corresponds to said second airflow setting, which is activated either before or after a period of ionization. More preferably, said ionization is performed without airflow or in conjunction with said second airflow setting.

[0038] The inventors have surprisingly found that a combination of moderate air flow rates and ionization treatment can prevent microbial growth and dramatically reduce the prevalence of live microorganisms blown into the ambient air and released into the environment during filter changes.

[0039] Such microorganisms include gram-positive bacteria, gram-negative bacteria, spores, molds and fungi, and any viruses within the aforementioned microorganisms.

[0040] The inventors have surprisingly found that providing a low-velocity air draft followed by a burst of ionization, or vice versa, can dramatically reduce the viability of microorganisms on the interior surfaces of an air purifier, particularly on the filter media. While the purifier is operating, there is no increased risk of microorganisms growing and multiplying on the filter. However, when the purifier is in idle or standby mode and conditions are favorable, microorganisms do multiply.

[0041] In a preferred embodiment of the present invention, the purifier checks for possible conditions conducive to microbial growth and, if such conditions are deemed to exist, activates the airflow generator and / or ionizer to destroy the microorganisms on the filter or even on the interior surfaces of the purifier. Preferred means for assessing whether conditions are conducive to microbial growth include humidity and temperature sensors.

[0042] If the processor determines that the conditions are conducive to microbial growth, it provides an indication, for example by a visual or audible signal or electronically to a remote device such as a cell phone, thereby informing the user that an airflow generator and / or ionizer should be used, or automatically operates a fan or impeller at a low speed as described herein, which is sufficient to prevent microbial growth or to directly destroy the microorganisms.

[0043] Preferably, the purifier has a first mode in which the options are either: no action when conditions determined by the humidity and temperature sensors are such that no or low microbial growth is expected; an alert via an electronic signal to the mobile device to alert the user that conditions are favorable for microorganisms and allow the user the option to activate the fan; and a warning level that alerts the user that microbial growth is likely and strongly recommends that the user activate the fan or impeller.

[0044] The second mode can operate similarly in that the instructions are determined by input from the temperature and humidity sensors, but instead of a warning or alert, the machine will automatically turn on when conditions are likely for microbial growth.

[0045] Of course, the user may select one of these two modes as appropriate.

[0046] Temperature sensors are known in the art and are commercially available from Sensirion. Suitable examples of temperature sensors include the STS3x series.

[0047] Humidity sensors are known in the art and are commercially available from Sensirion. Suitable examples of humidity sensors include the SHT3x series.

[0048] In a preferred embodiment, the means for controlling the airflow generator based on input from the sensor is performed automatically, for example, by a processor. In such an embodiment, the sensor continuously or intermittently senses temperature and / or humidity and sends information back to the processor. The processor determines whether conditions are conducive to microbial growth based on at least the temperature or humidity. Preferably, the processor determines whether conditions are conducive to microbial growth based on the temperature and humidity. More preferably, the processor determines the likelihood of microbial growth further based on parameters such as geographic location, time of day, week, month, or season, or pollution level, as well as any specific conditions occurring, such as a virus pandemic or bushfire, and any combination thereof.

[0049] For example, in Asia, the wet season is typically defined by the monsoon, which occurs in the summer. In contrast, summer in Europe and North America is characterized by drier weather. Similarly, the hemispheres have different seasonal characteristics.

[0050] Preferably, the geographic location is determined by GPS or the purifier's WIFI capabilities, which may also be provided by user input during the setup process.

[0051] The purifier may be powered by any suitable power source, including an internal power source, e.g., a battery, and an external power source. The power is used to drive a motor, which powers at least the airflow generator and ionizer, if present.

[0052] Preferably, the filter media comprises at least one of carbon, activated carbon, nonwoven fabric, thermoplastic material, thermoset material, porous foam, fiberglass, paper, high loft spunbond web, low loft spunbond web, meltblown web, and / or bimodal fiber diameter meltblown media.

[0053] Preferably, the removable particulate filter is a high-efficiency particulate air (HEPA) filter. While the filter portion of an air purifier is an important part of its function, it should be understood that air purifiers are not typically manufactured with filters in place. They are in fact always manufactured separately, and most importantly, often by commercial companies different from the manufacturer of the air purifier itself. It is also typical for filter manufacturers to manufacture filters for different air purifier models made by different manufacturers. A particulate filter should be contrasted with a pre-filter or any dust filter that may be present. Preferably, the filter is pre-charged before application to the air purifier.

[0054] Pre-filters are filters that have low air resistance and also function as poke guards to prevent the user from touching the volute or impeller assembly. Pre-filters are not intended to be highly effective in terms of air purification. They do not have the air resistance or particle entrainment capabilities of dedicated particulate filters. Preferably, pre-filters are not HEPA filters.

[0055] The purifier of the present invention also includes a fan or impeller, which may be a bladeless fan, an axial fan, or preferably a radial fan. [Brief explanation of the drawings]

[0056] [Figure 1] FIG. 1 illustrates a cross section of one embodiment. [Figure 2] FIG. 10 is a schematic diagram showing how the ion field generated by the ionizer arrangement immerses the filter in the ion stream during use. DETAILED DESCRIPTION OF THE INVENTION

[0057] Embodiments of the present invention will now be described with reference to the following, in which Figure 1 shows a cross section of one embodiment.

[0058] In particular, Figure 1 shows an air purifier (1) comprising a housing (2) and a fan (3) housed in a volute (4). The fan (3) is shown in simplified form without attempting to describe its physical characteristics or arrangement. The volute (4) comprises an outlet (5) through which air passes from the fan (3) to a filter (6). The filters (6) are connected at their upper edges (7) to form an apex. The volute outlet (5) also comprises an ion emitter (9) and an ion receiver (8) for generating an ion filed (not shown) that extends toward the filter (6).

[0059] In use, air enters the purifier from the ambient through an air inlet (10) which is secured by a pre-filter (12) which acts as an initial filter to prevent large items entrained in the airflow from entering and blocking the internal workings of the device, but also acts as a poke guard.

[0060] An air flow is then generated by the fan (3) and the air passes through a volute towards the filter (6) where it is cleaned.

[0061] The air then exits through the outlet (13), which is likewise secured with a pre-filter (11).

[0062] Figure 2 is a schematic diagram showing how the ion field generated by the ionizer configuration immerses the filter in the ion flow during use. Shown is the volute (4) and corona discharge tip (9), which generates an ion flow between the tip (9) and the receiving electrode (8) when an appropriate voltage is applied to the tip (9).

[0063] The ion cloud (20) extends away from the tip (9) and bathes the filter (6), providing a sterilizing effect.

[0064] [Example 1] The following experiment demonstrates the evaluation of the effect of ionization alone on the viability of microorganisms on a substrate, in this case a particulate filter. The ionizer was powered to -5 kV to emit a stream of ions.

[0065] The air flow applied to the substrate in this experiment was 0. The microorganisms used were Staphylococcus aureus and Pseudomonas aeruginosa, and the incubation period for generating biofilms was 5 days. result:

[0066] [Table 1]

[0067] [Table 2]

[0068] Conclusion: The closer the ionizer emitter is to the substrate, the better the impact on microbial viability. Additionally, bursts of ionization of approximately 2 hours work best.

Claims

1. A method for sterilizing an interior surface of an air cleaner or a filter media within an air cleaner by exposing the surface or the filter media to an ion cloud.

2. 10. The method of claim 1, wherein the air purifier comprises an ionizer configured to generate an ion cloud on the interior surface or the filter media.

3. 3. The method of claim 1 or 2, wherein the ionizer comprises a corona discharge tip positioned within 15 cm of the surface to be sterilized.

4. 4. The method of claim 1, wherein the air cleaner comprises a removable particulate or gas filter, an airflow generator, means for controlling the airflow generator, a first airflow setting having an air filtered airflow velocity, and a second airflow setting correlated with sterilization of an internal surface of the air cleaner and / or a removable particulate or gas filter.

5. An air purifier comprising a removable filter media, an air flow generator, and an ionizer, at least one airflow setting; a further setting in which the ionizer is activated in the absence of air flow or in combination with an air flow setting such that the filter media is subjected to an air flow of 0.1 to 1.2 cm / s; An air purifier equipped with

6. An air purifier comprising a removable filter media, an airflow generator and ionizer, a temperature sensor, and a humidity sensor.

7. 7. The air purifier of claim 6, wherein the ionizer is disposed on the removable filter media.

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