CN110617602A

CN110617602A - Fresh air purifier monitoring

Info

Publication number: CN110617602A
Application number: CN201910521056.4A
Authority: CN
Inventors: D·P·凯莉; 苏婧
Original assignee: Koninklijke Philips NV
Current assignee: Fansongni Holdings Ltd
Priority date: 2018-06-19
Filing date: 2019-06-17
Publication date: 2019-12-27

Abstract

Embodiments of the present disclosure relate to a fresh air purifier monitoring system (10) for monitoring a fresh air purifier (50) having a duct (54) for connecting an outdoor space to an indoor space (1) housing the fresh air purifier, the duct comprising a particle filter (63) for removing particles from outdoor air (82) introduced from the outdoor space into the indoor space through the fresh air purifier. Fresh air purifier monitoring system includes a response chamberCO in the inner space₂A processor (31) of the sensor (21), wherein the processor is configured to derive the CO from the air during said air introduction₂The sensor receives a series of readings, each of the readings being indicative of CO within the indoor space₂Horizontal; determining CO in an indoor space from a received series of readings₂A rate of decrease of the level; and from CO in the indoor space₂The determined rate of decrease of the level determines a state of the particulate filter. Also disclosed is a fresh air purifier system, including such a fresh air purifier monitoring system and a method of monitoring such a fresh air purifier system.

Description

Fresh air purifier monitoring

Technical Field

The present invention relates to a fresh air purifier monitoring system for monitoring a fresh air purifier having a duct for connecting an outdoor space to an indoor space housing the air purifier, the duct comprising a particulate filter for removing particles from outdoor air introduced from the outdoor space into the indoor space by the fresh air purifier, the system comprising a processor configured to determine a status of the particulate filter.

The invention also relates to a fresh air purifier system comprising such a fresh air purifier monitoring system.

The invention also relates to a method of monitoring a fresh air purifier having a duct for connecting an outdoor space to an indoor space housing the air purifier, the duct comprising a particle filter for removing particles from outdoor air, which is introduced from the outdoor space into the indoor space through the fresh air purifier.

Background

In today's society, it is common for air purifiers to clean air in enclosed spaces (e.g., rooms), for example, to reduce exposure of people to harmful or unpleasant contaminants, such as allergens, particulates, odors, etc., in such enclosed spaces. One particular type of air purification system includes a Fresh Air Purification Unit (FAPU), or simply fresh air purifier, wherein fresh air, i.e., outdoor air, is introduced into an enclosed space after passing through one or more contaminant removal structures (e.g., particulate filters, such as HEPA filters) to at least partially remove contaminants such as particulate matter, NOx, ozone, etc. from the fresh air, which contaminants may cause health problems, such as respiratory diseases, e.g., asthma, if the patient is exposed to such conditions.

Such contaminant removal structures, and in particular particulate filters, typically have a limited lifetime and therefore must be replaced or repaired periodically to ensure that the air purifier has the required performance characteristics of adequately purifying the air within the enclosed space in which the air purifier is disposed, e.g., a room of a building such as an office space or a house.

However, it is not straightforward to predict when such particulate filters need replacement or maintenance. Given that such particulate filters can be quite expensive, it is desirable that such particulate filters not be replaced or repaired prematurely, as this can significantly increase the operating costs of the fresh air purifier. On the other hand, if particulate filter replacement or repair is delayed beyond its end of life (EOL), the performance of a fresh air purifier including a particulate filter may become insufficient, which may cause health problems for people occupying the enclosed space in which the fresh air purifier is placed. This is especially prevalent in certain risk groups; there is ample evidence to suggest that pregnant women, infants/children, the elderly and people with respiratory or cardiovascular disease are at increased risk of exposure to contaminants. For these groups, it is desirable to minimize their exposure to air pollution.

Several fresh air purifier manufacturers maintain a fixed EOL value for particulate filters in fresh air purifiers in order to periodically prompt users to replace or repair such filters, for example, based on the cumulative operating time of the fresh air purifier or based on fixed intervals recommended by the fresh air purifier manufacturer. However, this approximation does not take into account environmental conditions and operating times, and therefore may result in a rather inaccurate approximation of the EOL of these particulate filters. For example, in cities where fresh air purifiers are heavily polluted, their particulate filters need to be replaced more frequently.

US2016/0209316a1 discloses a method for determining the fouling rate of at least one filter of a ventilation and/or air treatment system by calculating the amount of dust retained by the filter based on the theoretical filtration capacity of the filter, collected pollution data of the air passing through the filter and the air flow into a ventilation system comprising the filter. However, this approach can be quite inaccurate, for example because the air flow through the filter is not constant, but rather a function of its degree of fouling.

Disclosure of Invention

The present invention aims to provide a fresh air purifier monitoring system adapted to more accurately determine a condition, such as the expected end of life of a particulate filter, in such a fresh air purifier.

The present invention is also directed to a fresh air purifier system including such a fresh air purifier monitoring system.

The present invention is also directed to a method of monitoring a fresh air purifier to more accurately determine a condition, such as an expected end of life of a particulate filter in such a fresh air purifier.

According to one aspect, there is provided a fresh air purifier monitoring system for monitoring a fresh air purifier, the fresh air purifier having ducting for connecting an outdoor space to an indoor space housing the fresh air purifier, the ducting including a particulate filter for removing particulates from outdoor air introduced into the indoor space from the outdoor space through the fresh air purifier, the system including a sensor responsive to CO within the indoor space₂A processor of the sensor, wherein the processor is configured to derive the CO from the air during the air introduction₂The sensor receives a series of readings, each of the readings being indicative of CO within the indoor space₂Horizontal; determining CO in an indoor space from a received series of readings₂A rate of decrease of the level; and from CO in the indoor space₂The determined rate of decrease of the level determines a state of the particulate filter.

The invention is based on the following insight: the flow of outdoor air through the duct of the fresh air purifier is a function of the state of the particulate filter, for exampleSuch as its particulate matter contamination level, wherein the air flow rate is generally reduced, e.g., the contamination level is increased, as the state of the particulate filter deteriorates. As outdoor air enters the indoor space, an overpressure is created in the indoor space which forces the indoor space to ventilate to its surroundings, which results in CO in the indoor space₂Due to low CO₂The horizontal outdoor air is introduced into the indoor space to be lowered. The rate at which this reduction occurs is a function of the magnitude of the overpressure, which in turn is a function of the outdoor air flow through the particulate filter, so that it may be based on the CO within the indoor space during the ventilation of outdoor air into the indoor space using the fresh air purifier₂Determining the state of the particulate filter assuming ambient CO at the determined rate of decrease of the level₂The level is constant. Alternatively, outdoor (ambient) CO₂The level can use external CO₂Sensors or data from internet services that provide the actual CO for the area in which the indoor space is located₂And (4) horizontal.

In an embodiment, the processor is configured to slave the CO within the indoor space₂An average of the plurality of determined rates of decrease of the levels determines a state of the particulate filter. This has the following advantages: avoiding CO based on single determination in indoor space₂The rate of decrease of the level (being a statistical outlier) without accurately determining the risk of the condition of the particulate filter.

The processor may be configured to: by comparing CO in the room space₂Determined rate of decrease of level and CO in indoor space₂A horizontal baseline rate of decrease to obtain an accurate determination of the condition of the particulate filter from the CO in the indoor space₂The determined rate of decrease of the level determines a state of the particulate filter.

The processor may be further configured to: from CO₂Determination of CO in indoor space from a series of readings of a sensor₂The baseline rate of decrease in level indicating when the particulate filter is uncontaminated, e.g., after installation of a fresh air purifier or after replacement of a particulate filter to obtain an indoor spaceInternal CO₂The maximum rate of decrease of the level (i.e. the maximum outdoor air flow through the fresh air purifier's duct) is immediately followed by the introduction of outdoor air from the outdoor space through the duct into the CO in the indoor space during the introduction of the indoor air into the indoor space by the fresh air purifier through the duct₂And (4) horizontal.

Alternatively, the processor is further configured to estimate CO within the indoor space using an algorithm comprising as algorithm parameters the volume of the indoor space and the ventilation rate between the indoor space and the outdoor space₂The horizontal baseline decreases the rate. This has the advantage that variations in the ventilation conditions of the indoor space can be compensated, which can improve the accuracy of the determination of the state of the particulate filter of the fresh air purifier. For example, the processor may also be configured to operate according to the slave CO when the fresh air purifier is not introducing outdoor air into the indoor space₂Estimating a ventilation rate between the indoor space and the outdoor space from at least one series of additional readings obtained by the sensor, each additional reading being indicative of CO within the indoor space₂And (4) horizontal.

In another embodiment, the processor is configured to determine the initial CO within the indoor space by determining the initial CO₂Horizontal and subsequent CO in the indoor space₂Time intervals between levels to determine the CO in the indoor space from the received series of readings₂The rate of level reduction. This facilitates a direct determination of the status of the particulate filter of the fresh air purifier, as its status may be directly related to the length of the determined time interval.

Initial CO₂The level may be a level that triggers the fresh air purifier to initiate the introduction of the outdoor air into the indoor space. In an exemplary embodiment, this is at least 1000ppm, and may be at least 1500 ppm.

In another embodiment, the processor is configured to determine the CO in the indoor space₂The determined rate of decrease of the level determines a state of the particulate filter, and the processor is further configured to predict at least one of a remaining life of the particulate filter and a remaining capacity of the particulate filter based on the determined state. This information is for the user of the fresh air purifier to determineIt is useful when the particulate filter needs to be replaced.

According to another aspect, there is provided a fresh air purifier system comprising a fresh air purifier having ducting for connecting an outdoor space to an indoor space housing the fresh air purifier, the ducting comprising a particulate filter for removing particulates from outdoor air introduced into the indoor space from the outdoor space through the fresh air purifier and fresh air purifier monitoring system of any of the embodiments described herein. Such fresh air purification systems benefit from being able to accurately determine the status of their particulate filter by including an air purifier monitoring system.

The fresh air purifier system may also include CO₂Sensors to provide a completely independent system.

According to yet another aspect, a method of monitoring a fresh air purifier having ducting for connecting an outdoor space to an indoor space housing the air purifier, the ducting including a particulate filter for removing particulates from outdoor air introduced from the outdoor space into the indoor space through the fresh air purifier is provided. The method comprises the following steps: introducing outdoor air into the indoor space through the duct by using the fresh air cleaner, and removing CO from the indoor space₂The sensor receives a series of readings, each reading indicative of CO within the indoor space₂Horizontal; determining CO in an indoor space from a received series of readings₂A rate of decrease of the level; and from CO in the indoor space₂The determined rate of decrease of the level determines a state of the particulate filter. By correlating the state of the particulate filter with the CO in the indoor space during a ventilation event with a fresh air purifier₂The rate of decrease of the level correlates and the state of the particulate filter can be accurately determined.

In an embodiment, the CO in the indoor space is selected from₂Determining the state of the particulate filter from the determined rate of decrease in level comprises: comparing CO in indoor space₂Determined rate of decrease of levelRatio and CO in indoor space₂A baseline rate of decrease of the level to accurately determine the condition of the particulate filter.

The method may further include predicting at least one of a remaining life of the particulate filter and a remaining capacity of the particulate filter based on the determined state such that a user of the fresh air purifier may be notified when the particulate filter needs to be replaced.

Drawings

Embodiments of the invention are described in more detail, by way of non-limiting examples, with reference to the accompanying drawings, in which:

fig. 1 schematically shows an air purification device comprising a fresh air purification monitoring system according to an embodiment;

fig. 2 schematically shows an air purification device comprising a fresh air purification monitoring system according to another embodiment;

fig. 3 schematically shows a fresh air purification apparatus according to an example embodiment;

fig. 4 schematically shows a fresh air purification apparatus according to another exemplary embodiment;

fig. 5 schematically shows a fresh air purification apparatus according to yet another exemplary embodiment;

fig. 6 schematically shows a fresh air purification apparatus according to yet another exemplary embodiment;

FIG. 7 is a flow diagram of a method of monitoring a fresh air purification apparatus located in an indoor space, according to an embodiment;

FIGS. 8 and 9 are diagrams illustrating CO in an indoor space for different states of a particulate filter thereof during operation of a fresh air purification apparatus₂A graph of the rate of decrease;

fig. 10 shows a set of charts associated with a first ventilation condition of a room in which a fresh air purification apparatus according to an embodiment of the present invention is placed; and

fig. 11 shows a set of graphs associated with a second ventilating condition of a room in which a fresh air cleaning apparatus according to an embodiment of the present invention is placed.

Detailed Description

It should be understood that the figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the figures to indicate the same or similar parts.

Fig. 1 schematically shows a fresh air purification monitoring system 10 according to an embodiment. The fresh air purification monitoring system 10 is adapted to control the operation of an air purification apparatus 50 installed into an indoor space 1 (e.g., a room of a house, an office building, etc.). As will be explained in further detail below, the fresh air purification apparatus 50 may be operated in a first mode in which outdoor air is ventilated into the indoor space 1 and a second mode in which indoor air within the indoor air 1 is circulated through the fresh air purification apparatus 50. Such air flow is typically passed through one or more pollutant removing structures installed within the fresh air cleaning apparatus 50 to clean the air before it is discharged into the indoor space 1. In particular, the fresh air cleaning device 50 comprises a particle filter, for example a HEPA filter, through which the outdoor air passes when being ventilated into the indoor space 1, in order to capture particulate matter in the outdoor air before passing the outdoor air to the indoor space 1. Such a fresh air cleaning device 50 may be installed in any suitable manner within the indoor space 1, for example through an exterior wall, roof or window of a house or building housing the space 1, so that the fresh air cleaning device 50 may contact an outdoor space from which outdoor air comes. Such fresh air purification apparatus 50 may comprise, in addition to the particulate filter, any suitable type of contaminant removal structure, such as a filter, e.g., a carbon filter or the like, to remove contaminants, such as pollen, odors, bacteria, Volatile Organic Compounds (VOCs) such as formaldehyde and toluene, and the like.

The fresh air purification monitoring system 10 generally includes a computing device 30 that includes a processor 31. The computing device 30 may be any suitable computing device, such as a personal computer, e.g., a desktop or notebook computer, a tablet computer, a personal digital assistant, a mobile communication device such as a smartphone, and the like. The computing device 30 may form an assembly with the air purifier 50. In such an assembly, the computing device 30 may be a discrete entity or may form part of the fresh air purifier 50, i.e. the fresh air purifier 50 may comprise the processor 31. The processor 31 may be any suitable processor, such as a general purpose processor or a special purpose processor. The computing device 30 may also include a data storage device 33 communicatively coupled to the processor 31.

The computing means 30 is arranged to communicate with one or more sensors 21, 23 for sensing the level of the undesired substances of interest in the atmosphere within the indoor space 1 in which the fresh air cleaning device 50 is placed. The first sensor 21 is typically CO₂A sensor arranged to monitor CO in the indoor space 1₂And (4) horizontal. The second sensor 23 (when present) may be an adverse substance sensor arranged to sense a concentration or level of an adverse substance for which the fresh air cleaning apparatus 50 comprises a pollutant removal structure, such as an air filter or the like, arranged to remove this adverse substance. For example, the further sensor 23 may be a particulate matter sensor, such as a PM2.5 sensor, for detecting particulate matter of a certain diameter in the atmosphere, such as PM2.5 or PM10, dust particles, allergens etc., a formaldehyde sensor, a toluene sensor etc. As can be appreciated from the foregoing, the presence of the further sensor 23 is optional and may be omitted from certain embodiments of the invention.

The sensors 21, 23 may be integrated in any suitable device, such as the fresh air cleaning apparatus 50, the computing device 30 or a separate sensor device 20, such as a sensor cartridge or the like. Standalone sensor devices, such as sensor cartridges, are increasingly available for home use and may include sensors for measuring air pollutants, such as Volatile Organic Compounds (VOCs) including formaldehyde and toluene, particles including PM2.5, and environmental parameters such as relative humidity and temperature. The processor 31 may be adapted to monitor the concentration of a specific contaminant based on sensor data provided by the sensors 21 of the sensor device 20. In an embodiment, the processor 31 may be integrated into such a separate sensor device 20, i.e. the separate sensor device 20 may comprise the computing device 30.

The sensors 21, 23 are communicatively coupled to the computing device 30 by a communication link 25 so that the processor 31 can receive sensor readings from the sensors. Such a communication link may be a wired communication link, for example in case the sensors 21, 23 are integrated with the computing device 30, or may be a wireless communication link, for example in case the sensors 21, 23 are located in a different device than the computing device 30, for example in a separate sensor device 20. To this end, the various devices communicatively coupled by such wireless communication links may include wireless transceivers (not shown). The devices may communicate with each other using any suitable wireless communication protocol, e.g., bluetooth, Wi-Fi, mobile communication protocols such as 2G, 3G, 4G or 5G, suitable Near Field Communication (NFC) protocols or proprietary protocols, through their respective wireless transceivers. In the case of such wireless communication, the respective devices may communicate directly with each other or may communicate with each other through an intermediary such as a wireless bridge, router, hub, or the like. Embodiments of any suitable wired or wireless communication between these respective devices are contemplated.

The processor 31 may be further communicatively coupled to a data storage device 33, here shown as forming part of the computing device 30. Such data storage means may be any suitable device for storing digital data, e.g. random access memory, cache memory, flash memory, solid state memory devices, magnetic storage devices such as hard disks, optical storage devices, etc. Alternatively, data storage 33 may be separate from computing device 30, such as a network storage or cloud storage accessible to processor 31 over a network such as a LAN or the internet. The processor 31 may store sensor data received from one or more connected sensors 21, 23 in a data storage device in order to collect and store historical data regarding the level of undesirable substances in the atmosphere within the indoor space 1, including the fresh air cleaning apparatus 50, from which the processor 31 may obtain certain parameters relating to the indoor space 1, as will be described in further detail below.

In fig. 1, the computing apparatus 30 further includes a sensory output device 35 under the control of the processor 31. Such a sensory output device may be any apparatus capable of producing an output detectable by one of the human senses. For example, the sensory output device 35 may be adapted to produce a visible output or an audible output. For example, the sensory output device 35 may include a display and/or one or more LEDs adapted to provide such output. As will be explained in further detail below, in at least some embodiments, the sensory output device 35 may be controlled by the processor 31 to produce a sensory output indicative of the end-of-life of the particulate filter within the air purification apparatus 50. Such end-of-life indication may be an indication of the remaining life of the particulate filter, an indication of the remaining filter capacity of the particulate filter, an indication that the particulate filter has reached the end of its life and needs to be replaced, and so on. The end-of-life of the particulate filter may be defined in terms of the actual filter capacity of the particulate filter; for example, the processor 31 may determine that the particulate filter has reached the end of its life when the actual filter capacity of the particulate filter is 50% or less of its initial filter capacity.

In the above embodiments, the sensory output device 35 forms part of the computing apparatus 30, for example may be an integral part of the computing apparatus 30, or may be attached to the computing apparatus 30, for example to a monitor or speaker of the computing apparatus 30. In an alternative arrangement, schematically depicted in fig. 2, the sensory output device 35 may form part of a mobile communication apparatus 40, wherein the computing apparatus 30 is adapted to communicate with the mobile communication apparatus via a wireless communication link 37, for example using any of the above-mentioned wireless communication protocols. In this embodiment, the operation of the air cleaning apparatus 50 may be controlled even if not in the vicinity of the computing device 30, for example when in a different room or outside a building comprising the fresh air cleaning apparatus 50, which may for example be advantageous to ensure that the indoor space 1 is adjusted to a desired state in anticipation of a user of the mobile communication device 40 reaching the indoor space 1. Any suitable mobile communication device 40, such as a smart phone, tablet, personal digital assistant, etc., may be used for this purpose. As will be readily understood by those skilled in the art, mobile communication device 40 may be configured with a software application, such as an app, to interact with computing device 30 as described above.

In a further embodiment, the adverse substance sensors 21 and 23, as well as the processor 31 and the sensor output device 35, are integrated in the fresh air purification device 50, thereby forming an integrated fresh air purification device 50 according to an embodiment of the present invention.

Next, some examples of the fresh air purifying apparatus 50 according to an embodiment of the present invention will be described in more detail. A first example is schematically shown in fig. 3, which depicts a fresh air cleaning device 50, which is adapted to generate a first air flow 81, from here called recirculation air flow 81, a second air flow 82, from here called ventilation air flow 82, and a third air flow 83, from here called exhaust air flow 83.

The recirculation air flow 81 recirculates air from within the indoor space into the indoor space 1 through the contaminant removal structure 61 in the duct located between the indoor inlet 55 and the first indoor outlet 53 of the fresh air purification apparatus 50, thereby reducing the concentration of indoor adverse substances and purifying the indoor air. The recycled air stream 81 may be generated using a first air displacement device or means 67, such as a fan, ventilator, ion wind generator, air pump, or the like.

The ventilation air flow 82 introduces air from the outdoor space into the indoor space 1 through the particulate filter 63 in the further duct between the outdoor inlet 57 and the second indoor outlet 51 of the fresh air cleaning device 50, thereby reducing the concentration of outdoor particulate matter to be introduced into the indoor space 1. The further duct may further accommodate a heat exchanger 70 which conditions the outdoor air, e.g. heats or cools the outdoor air, for climate control, before it is introduced into the indoor space 1, as is well known per se. The ventilation air stream 81 may be generated using a second air displacement device or apparatus 69, such as a fan, ventilator, ion wind generator, air pump, or the like.

The ventilation air flow 82 can be used to generate a relative outdoor air flow in the indoor space 1Positive pressure of the space, thereby forcing air from the indoor space 1, i.e. ventilating the indoor space 1, for example in order to reduce the concentration of undesired substances generated within the indoor space 1, for example to reduce VOCs in the case of a newly finished indoor space 1 or human CO present in the indoor space 1₂The concentration of (c).

The exhaust airflow 83 may be used to assist in such ventilation by forcibly exhausting indoor air under the control of the second air displacing device or means 69, by way of non-limiting example only. Alternatively, a third, second air displacing device or means (not shown) may be used for this purpose. The exhaust airflow 83 may also pass through yet another duct extending between the indoor inlet, such as the second inlet 51, and the outdoor outlet 59. As will be readily understood by those skilled in the art, a valve arrangement 65 may be present to switch the operation of the second air displacing device or arrangement 69 between the generation of the ventilation air stream 82 and the exhaust air stream 83.

As previously described, the contaminant removal structure 61 and the particulate filter 63 within the fresh air purification apparatus 50 may be configured to remove any suitable undesirable substances, such as O, from the indoor air or the outdoor air₃、PM10、PM2.5、CO、NO₂、SO₂Volatile organic compounds such as formaldehyde or toluene, and the like. It should also be understood that according to embodiments of the present invention, the fresh air cleaning device 50 is arranged to generate at least a recirculation air flow 81 and a ventilation air flow 82, which may be achieved by any suitable configuration of the fresh air cleaning device 50. For example, fig. 4 schematically depicts another exemplary embodiment of a fresh air purification apparatus 50, wherein the fresh air purification apparatus 50 is configured to generate a recirculation air flow 81 and a ventilation air flow 82 using only the individual air displacement apparatuses 67, 69 as previously contacted, while fig. 5 schematically depicts another exemplary embodiment of a fresh air purification apparatus 50, wherein a recirculation air flow 81 and a ventilation air flow 82 are generated using a single air displacement apparatus 67, which is communicatively connected to a valve arrangement 65, which allows the air purification apparatus 50 to switch between the recirculation air flow 81 and the ventilation air flow 82 or a mixture thereof.

Fig. 5 further schematically shows that the recirculation air flow 81 and the ventilation air flow 82 share the same indoor outlet 53 of the fresh air purification apparatus 50, and it should be understood that these air flows may share such an outlet in any one embodiment of the fresh air purification apparatus 50. It should also be understood that further configuration variants of the fresh air purification apparatus 50 are of course possible without departing from the teaching of the present invention, such that a given example configuration of the fresh air purification apparatus 50 should in no way be construed as limiting the scope of the present invention.

In some embodiments, the fresh air purification apparatus 50 may comprise at least a portion of the air purification monitoring system 10 and/or the sensor device 20. For example, the fresh air purification apparatus 50 may comprise a fresh air purification monitoring system 10 according to any of the described embodiments, which is communicatively coupled to a separate sensor device 20 according to any of the described embodiments. Alternatively, as schematically depicted in fig. 6, the fresh air purification apparatus 50 may comprise the fresh air purification monitoring system 10 according to any of the described embodiments and the sensor device 20 according to any of the described embodiments, and the sensor device 20 comprises at least CO₂A sensor 21. As mentioned before, the air displacing device 67 of the fresh air cleaning device 50 is controlled by the processor 31 and is arranged to introduce outdoor air through the inlet 57 into the indoor space 1 through the outlet 51, wherein the duct 54 is defined by the inlet 57 and the outlet 51, the duct comprising the particle filter 63 as mentioned before between the inlet 57 and the outlet 51. As will be readily understood by those skilled in the art, the housing 52 of the fresh air purification apparatus 50 may further define a duct 54.

Alternatively, the fresh air purification apparatus 50 may comprise a wired or wireless communication module (not shown) adapted to communicate with the air purification monitoring system 10 according to any of the described embodiments, which may itself be communicatively coupled to the individual sensor device 20 according to any of the described embodiments. In this case, the fresh air cleaning device 50 further comprises controller means (not shown) of one or more air displacing devices 67, 69, which controller means control the one or more air displacing devices 67, 69 in dependence of the control signals generated by the processor 31. In the context of the present application, such a control signal may comprise one or more control instructions for the fresh air cleaning device 50. Such control instructions configure the fresh air cleaning device 50 to operate in a specific mode and may thus instruct the fresh air cleaning device 50 to operate any air displacing device 67, 69, valve arrangement 65 (if present) etc. in accordance with the configuration information conveyed by the control signal.

According to an embodiment of the invention, the processor 31 is adapted to implement a method 100, a flowchart of which is depicted in fig. 7. More specifically, the processor 31 is arranged to determine the slave CO in accordance with the monitoring period₂Sensor signals periodically received by the sensor 21 from the CO in the indoor space 1₂The rate of decrease of the level estimates the state of the particulate filter 63. This can be understood as follows. The processor 31 may be configured to process the CO in the indoor space₂When the concentration reaches a critical level (for example 1000ppm, 1500ppm or other defined critical level), the fresh air purification device 50 is switched into its ventilation mode. This results in outdoor air being forced into the indoor space 1, the outdoor air having ambient CO₂Horizontal, i.e. lower, CO₂Levels, for example, about 350 and 450 ppm. This also increases the air pressure in the indoor space 1, which results in increased ventilation between the indoor space 1 and its surroundings, thereby reducing the CO in the indoor space 1₂And (4) horizontal.

These COs₂The rate at which the level decreases depends on the magnitude of the overpressure (relative to the ambient pressure) inside the indoor space 1, i.e. the rate at which the fresh air cleaning device 50 introduces outdoor air into the indoor space 1. The rate at which the fresh air cleaning apparatus 50 introduces outdoor air into the indoor space 1 is a function of the state of the particulate filter 63. For a new (uncontaminated) particulate filter 63, the air flow is not limited by any contamination on the particulate filter 63, so that the air flow is maximum for the new particulate filter 63. However, as the contamination (i.e., deteriorating condition) of the particulate filter 63 increases, the air flow rate gradually decreases (is restricted), so that CO in the indoor space 1 is caused to flow out₂The rate of horizontal decrease decreases accordingly. Thus, by purifying in fresh airDetermining the CO in the indoor space 1 when the device 50 is operated in its ventilation mode₂The actual rate of decrease of the level may determine the condition of the particulate filter 63.

According to the method 100, the method is performed by activating the processor 31 and the CO₂The ventilation mode of the sensor 21 and the fresh air cleaning device 50, during which the fresh air cleaning device 50 introduces outdoor air into the indoor space 1, starts in operation 101. When the CO in the indoor space 1 is present as described above₂Such a ventilation mode may be activated, for example, by processor 31, when the level reaches a critical threshold, such as 1000ppm, 1500ppm, or any other suitably defined critical value. The method then proceeds to operation 103, where the processor 31 periodically slave the CO to₂The sensor 21 receives a signal indicating the actual CO in the indoor space 1₂Horizontal CO₂And (6) reading.

In operation 105, the processor 31 checks the actual CO in the indoor space 1₂Whether the level corresponds to a further threshold, for example such a threshold: at this threshold, the CO in the indoor space 1₂The level is sufficiently low to disable the ventilation mode of the fresh air purification device 50, e.g. about 350-₂A threshold for any reduction in the level, such as 500ppm, 600ppm, 700ppm, 800ppm or any other arbitrary value. If the additional threshold has not been reached, the method 100 returns to operation 103. Otherwise, the method 100 proceeds to operation 107, where the processor 31 determines the CO within the indoor space 1₂Level (R)_CO2) For example, using the following formula (1):

R_CO2＝([CO₂]_t0-[CO₂]_t1)/(t1-t0)(1)

in the formula (1), [ CO ]₂]_t0Is the initial CO in the indoor space 1 at time t-t 0₂Level, [ CO ]₂]_t1Is the threshold value CO in the room space 1 at time t-t 1₂Horizontal, and t1-t0 are the initial CO₂The level is reduced to a threshold value CO₂Horizontal time interval. To this end, the processor 31 may include a clock or timer to determine the time interval. Alternatively to this, the first and second electrodes may be,the processor 31 may be at known regular intervals from the CO₂Sensor 21 receives CO₂Read so that the processor 31 can calculate the slave CO during the monitoring period₂CO received by sensor 21₂The total number of readings until the threshold CO is received₂Horizontal and including reception of a threshold value CO₂The level determines the time interval.

The processor 31 then bases the CO in the indoor space 1 in operation 109₂The determined rate of decrease of the level determines the status of the particulate filter 63, such as a HEPA filter. For example, the processor 31 may use the CO in the indoor space 1₂A horizontal defined optimal rate of decrease corresponding to an optimal airflow through the air cleaning device 50 when the particulate filter 63 is new (uncontaminated), and comparing the CO in the indoor space 1 determined in operation 107₂Actual rate of decrease of level and CO in the indoor space 1₂A defined optimal rate of decrease of the level. CO in the indoor space 1 determined in operation 107₂Actual rate of decrease of level and CO in the indoor space 1₂The difference between the defined optimal rates of reduction of the levels is related to the actual state of the particle filter 63 as described before, since the degree of contamination of the particle filter 63 directly affects the outdoor air flow through the air cleaning device 50 in its ventilation mode.

This is illustrated in fig. 8 and 9, which respectively depict the volume at 50m in fig. 8 and 9³CO in the room₂Horizontal simulated rate of decrease chart, CO is produced in the room at a rate of 0.031kg/h₂(e.g., by one or more persons in the room) and the room has 250m using the fresh air purification apparatus 50 according to an exemplary embodiment of the present invention³Natural ventilation rate per hour. In fig. 8, the fresh air cleaning device 50 is equipped with a new uncontaminated particulate filter 63, whereas in fig. 9 the fresh air cleaning device 50 is equipped with an old particulate filter 63 having a certain degree of particulate matter trapped thereon. It can be seen that in FIG. 8, the CO in the room₂The level decreased from 1500ppm to 600ppm in about 20 minutes,whereas in fig. 9, CO is due to the fact that the air flow through the fresh air cleaning apparatus 50 is limited by the particulate matter accumulation of the particulate filter 63₂The same reduction in level took about 40 minutes.

In a further refinement, the processor 31 is configured to be based on CO from within the indoor space 1₂Multiple determined actual reduction rate of level of CO in obtained indoor space 1₂The average rate of decrease of the level to determine the condition of the particulate filter 63, such as a HEPA filter. Due to CO in the indoor space 1₂The single determined rate of decrease of the level is a statistical outlier which reduces the risk that the state of the particle filter 63 is inaccurately determined, for example due to sudden changes in the volume of the indoor space 1 or the ventilation conditions, which may be the case.

The processor 31 may be configured to generate an end-of-life indication for the particulate filter 63 based on the state of the particulate filter determined in operation 109. Such end-of-life indication may be generated on the sensory output device 35 and may be an indication of a point in time at which the particulate filter 63 is expected to need to be replaced to ensure effective filtering of particulate matter using the fresh air purification apparatus 50, or an indication that the particulate filter 63 has reached its useful life and needs to be replaced immediately. Alternatively, such end-of-life indication may be an indication of the remaining capacity of the filter, e.g. expressed as a percentage of its original filter capacity, wherein the sub-optimal filter capacity of the particulate filter 63 indicating that replacement is required may be indicated in a different manner, e.g. using a different color when the sensory output device 35 is a display or LED arrangement. Many other useful expressions of the state of the particulate filter 63 will be apparent to those skilled in the art, and it should be understood that any such useful expression may be used to express the state of the particulate filter 63 in the context of the present application. After completing operation 109, the method terminates at 111.

In an embodiment, the processor 31 is configured to determine the reference time t_bWith CO in the indoor space 1₂The actual time t it takes for the level to reach the further threshold applied in operation 105_aIn betweenThe difference value determines the state of the particulate filter 63. In this embodiment, the reference time t_bIs the CO in the indoor space 1 when the particulate filter 63 is new₂The time it takes for the level to reach the further threshold. Preferably, the processor 31 is operable in a learning mode or a calibration mode, which may be invoked when the fresh air purification apparatus 50 is installed in the indoor space 1 or each time a new particle filter 63 is installed in the fresh air purification apparatus 50, so that the processor 31 may determine the reference time t of its uncontaminated particle filter 63 during this learning mode or calibration mode_b. This has the following advantages: the processor 31 does not need to be provided with explicit knowledge of the volume of the indoor space 1 and the natural ventilation conditions and the CO within the indoor space 1₂The rate is generated (e.g., by its residents).

Processor 63 may use t_bAnd t_aThe difference therebetween to determine the state of the particulate filter 63. E.g. at t_a≥2*t_bIn this case, the particulate filter 63 may be deemed to have reached its end of life such that the processor 63 may generate an end of life indication generated by the sensory output device 35. At t_b≤t_a≤2*t_bIn the case of (2), the ratio t_a/t_bMay be used to estimate the remaining capacity or life of the particulate filter 63, as previously described. It should be noted that preferably this estimation is based on CO from within the indoor space 1₂Multiple determinations of actual rate of decrease of level (e.g. t)_aDetermination of (c) to avoid the estimation being compromised by statistical outliers.

Hereinbefore, the CO in the indoor space 1₂The baseline rate of decrease of the level may be determined by the processor 31 using a learning mode or a calibration mode as previously explained. However, in an alternative embodiment, based on the volume V (in m) of the indoor space 1³) Natural ventilation rate Q (unit m) of indoor space 1³H), indoor and outdoor CO₂Concentration C_roomAnd C_outdoor(unit is g/m)³) And CO in the indoor space 1₂Source intensity (g/m)³) I.e. in the indoor space 1, e.g. by the number in the indoor space 1CO production by residents₂Can be estimated by the processor 31 for CO in the indoor space 1₂The horizontal baseline decreases the rate.

With respect to the determination of the volume of the indoor space 1, in a straightforward embodiment, the volume may be specified by a user using any user interface communicatively coupled to the processor 31. This therefore relies on the user providing an accurate estimate of the volume of the enclosed space 1.

In an alternative embodiment, the volume of the indoor space 1 may be estimated based on sensor information provided by the sensor device 20. In particular, the room volume may be derived from the indoor particle (pollutant) concentration, e.g. monitored with the further sensor 23, which follows equation 3 based on the law of conservation of mass:

in the formula:

c indoor particle concentration, g/m³；

P_pThe penetration coefficient of particles from the outside into the air-filled space containing the fresh air cleaning device 50, which in a typical domestic dwelling is typically around 0.8;

C_outoutdoor particle concentration, g/m³；

k₀Natural settling rate of the particles, h^-1Generally at 0.2h^-1Left and right;

k_vrate of ventilation, h^-1；

V room volume, m³；

CADR clean air delivery Rate, m³/h。

A typical CADR curve may be recorded by a sensor, which may be part of the sensor arrangement 20, which may be represented, for example, using a linear scale on the y-axis of a plot depicting the CADR curve. The recorded CADR curve can be expressed by equation (4):

C＝m*e^-kt (4)

thus, k is the exponential decay constant for the concentration curve.

By combining equations (3) and (4), the following equation (5) is obtained:

by substituting-km e^-ktEquation (6) can be obtained as follows:

the initial CADR can be used to calculate the room volume V₀I.e. the volume V of the indoor space 1 accommodating the fresh air cleaning device 50. This room volume can be obtained, for example, when the fresh air purifying apparatus 50 is operated for the first time in the hermetically sealed indoor space 1. Other suitable ways of obtaining the room volume may alternatively be applied.

The processor 31 may be adapted to: based on the CO in the indoor space 1 accommodating the fresh air cleaning apparatus 50 when one or more persons are present in the plenum space and the fresh air cleaning apparatus 50 is turned off₂The natural draft rate Q is estimated as a change in concentration or any other suitable gaseous compound, such as a Volatile Organic Compound (VOC). In particular, when these people exhale CO₂When, CO in the gas-filled space₂The level should increase according to the number of people in the inflated space and its volume. Deviation from this expected increase, i.e. CO₂A smaller increase in the level over time than expected can be attributed to ventilation between the plenum and the outside. For example, aThe processor 31 may be adapted to estimate the ventilation rate Q according to equation (7):

in equation (7), croom (t) is CO in the indoor space 1 at the time point t₂Concentration (in g/m)³In units), i.e. a time period deltat (in hours) after the start of the monitoring period at t-0, C_outdoorIs ambient CO in an environment ventilated with the gas-filled space₂Concentration (in g/m)³In units) and S is CO in the plenum₂Source intensity (in g/m)³In units). Individuals (S)_i) CO of₂The source intensity is typically within a given range (e.g., within the range of 0.16-0.33l/min for adults). The processor 31 may calculate the source intensity S based on the determined number N of individuals within the plenum, e.g., S ═ N × S_i。

The number N of individuals within the plenum may be determined in any suitable manner, for example, the number N may be specified by a user through a user interface of the fresh air purification monitoring system 10, or alternatively, the fresh air purification monitoring system 10 may include one or more sensors (not shown), such as motion detection sensors or the like, for detecting the presence of individuals within the plenum.

FIGS. 10 and 11 depict graphs, including plots of CO as a function of time₂Source intensity S (top left), Natural Ventilation Rate Q (top right) and CO₂Graph of concentration croom (t) (lower left). In fig. 10, the indoor space 1 exhibits a low ventilation rate, and in fig. 11, the indoor space 1 exhibits a high ventilation rate, which is evidenced by a high fluctuation in the natural ventilation rate Q due to a change in environmental conditions such as wind conditions. This results in CO in the interior space 1₂A significant difference in accumulation, which can be used to estimate the rate of spontaneous (natural) ventilation between the enclosed space 1 and the outdoor space. Thus, by taking into account the volume V of the indoor space 1, its natural ventilation rate Q and the source intensity S, the processor 31 can estimate that of the air cleaning device 50 with optimal operation, i.e. with a clean particle filter 63CO in the indoor space 1₂The rate at which the level should be reduced. Such optimum performance parameters of the fresh air purification apparatus 50 can be programmed into the processor 31 or into the data storage 33 accessible to the processor 31.

The processor 31 may be based on slave CO₂The series of sensor signals received by the sensor 21 determines the natural ventilation rate Q between the enclosed space 1 accommodating the fresh air cleaning device 50 and the outside, since the CO in the indoor space 1₂The trend of the concentration can be used to determine the spontaneous rate Q of ventilation, i.e. the ventilation rate when the fresh air purification device 50 is switched off, as explained in more detail above with the aid of equation (7). It should be understood that equation (7) is provided as a non-limiting example only, and that a CO based on this CO may also be used₂The trend may derive other equations for the ventilation rate Q.

The processor 31 may obtain the ambient CO₂Concentration for determining the ventilation rate Q in any suitable manner, e.g. from additional CO placed in the environment₂Sensors or from a service on a network such as the internet that provides information about the CO in the area of interest₂(real-time) information of the concentration, the region of interest comprising the area in which the room space 1 is located. Processor 31 may obtain ambient CO at any suitable point in time₂And (4) concentration.

Alternatively, the natural draft rate Q may be determined by monitoring other gaseous compounds, such as volatile organic compounds, produced by people within the indoor space 1. It should also be understood that the source intensity S need not be limited to the production of CO by persons within the enclosed space 1₂. It is also possible, for example, that the source intensity S represents the release rate of another disadvantageous substance, such as a volatile organic compound, which is released in the newly decorated enclosed space 1. Alternatively, the spontaneous ventilation rate of the enclosed room 1 may be estimated in any other suitable manner, such as a user-specified estimation provided by a user interface in communication with the processor 31.

Of course the estimation of the room volume and the spontaneous ventilation rate can be further improved. For example, the processor 31 may receive information from the CO₂Sensor 21 or another sensor 23 (e.g. VO)C sensor), for example to monitor CO in the enclosed space 1₂And/or a change in VOC level, as such a change may be indicative of a change in the volume of the indoor space 1, such as opening or closing by a door or the like between the indoor space 1 and an adjacent space or a change in ventilation conditions between the plenum and the outside. The change of the volume of the indoor space 1 or the ventilation condition may be performed by CO₂And/or sudden changes in VOC levels (or levels of other contaminants, monitored to determine the occupancy rate of the enclosure 1 as previously described). For example, the CO is detected at the processor 31₂And/or a sudden change in VOC concentration, this may indicate a change in the volume of the indoor space 1 or a change in the ventilation conditions of the indoor space 1.

The processor 31 may distinguish between changes in volume and changes in ventilation conditions in the following manner. In the presence of monitored pollutants and CO₂In case of a change in the volume of the closed space 1 after an initial sudden change in the levels, these levels will gradually decrease until an equilibrium between the two communicating spaces is reached. In this case, CO₂Typical ambient CO levels typically remain above about 350-450ppm₂And (4) horizontal. In case of a change in ventilation conditions, CO in the indoor space 1₂The level will be in contact with the ambient CO₂The levels equilibrate rapidly, reaching levels of about 350-450 ppm.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps other than those listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several distinct elements. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

1. A fresh air purifier monitoring system (10) for monitoring a fresh air purifier (50), the fresh air purifier having a duct (54) for connecting an outdoor space to an indoor space (1) housing the fresh air purifier, the duct comprising a particle filter (63) for removing particles from outdoor air (82) introduced from the outdoor space into the indoor space through the fresh air purifier, the system comprising a CO-in the indoor space₂A processor (31) to which the sensor (21) is responsive, wherein the processor is configured to, during the air introduction:

from the CO₂A sensor receives a series of readings, each of the readings being indicative of CO within the indoor space₂Horizontal;

determining the CO within the indoor space from the received series of readings₂A rate of decrease of the level; and is

From the CO in the indoor space₂The determined rate of decrease of level determines a status of the particulate filter.

2. The fresh air purifier monitoring system (10) of claim 1, wherein the processor is configured to: from the CO in the indoor space (1)₂An average of the determined plurality of the reduction rates of the levels determines a state of the particulate filter (63).

3. The fresh air purifier monitoring system (10) of claim 1, wherein the processor (31) is configured to: by comparing the CO in the indoor space₂The determined rate of decrease in level and the CO within the indoor space₂A horizontal reference reduction rate from the CO in the indoor space (1)₂The determined rate of decrease of the level determines the particle filter (6)3) The state of (1).

4. The fresh air purifier monitoring system (10) of claim 3, wherein the processor (31) is further configured to: from the CO₂A series of readings of a sensor (21) determines the CO in the indoor space (1)₂The baseline rate of decrease in level, the reading being indicative of CO within the indoor space during introduction of the outdoor air (82) from the outdoor space to the indoor space by the fresh air purifier through the duct (54) when the particulate filter (63) is uncontaminated₂And (4) horizontal.

5. The fresh air purifier monitoring system (10) of claim 3, wherein the processor (31) is further configured to: estimating the CO within the indoor space (1) using the algorithm comprising the volume of the indoor space and the ventilation rate between the indoor space and the outdoor space as parameters of the algorithm₂The baseline rate of decrease in level.

6. The fresh air purifier monitoring system (10) of claim 5, wherein the processor (31) is further configured to: when the fresh air purifier (50) does not introduce outdoor air into the indoor space, according to the CO₂Estimating the ventilation rate between the indoor space (1) and the outdoor space by at least one series of further readings obtained by a sensor (21), each further reading being indicative of the CO within the indoor space₂And (4) horizontal.

7. The fresh air purifier monitoring system (10) of claim 1, wherein the processor (31) is configured to: by determining the initial CO in the indoor space (1)₂Horizontal and subsequent CO in the indoor space₂Time intervals between levels to determine the CO within the indoor space from the series of readings received₂The rate of decrease of the level.

8. The fresh air purifier monitoring system (10) of claim 7, wherein the initial CO₂The level is a level at which the air purifier (50) is triggered to initiate the introduction of the outdoor air into the indoor space (1).

9. The fresh air purifier monitoring system (10) of claim 8, wherein the initial CO₂The level is at least 1000 ppm.

10. The fresh air purifier monitoring system (10) of claim 1, wherein the processor (31) is configured to determine the CO within the indoor space₂The determined rate of decrease of level determines a state of the particulate filter, the processor being further configured to predict at least one of a particulate filter remaining life and a particulate filter remaining capacity based on the determined state.

11. A fresh air purifier system comprising a fresh air purifier (50) having a duct (54) for connecting an outdoor space to an indoor space (1) housing the fresh air purifier, the duct comprising a particle filter (63) for removing particles from outdoor air introduced from the outdoor space into the indoor space through the fresh air purifier and a fresh air purifier monitoring system (10) according to any one of claims 1-10.

12. The fresh air purifier system of claim 11 further comprising CO₂A sensor (21).

13. A method (100) of monitoring a fresh air purifier (50) having a duct (54) for connecting an outdoor space to an indoor space (1) housing the fresh air purifier, the duct comprising a particle filter (63) for removing particles from outdoor air introduced from the outdoor space into the indoor space through the fresh air purifier, the method comprising, during use of the fresh air purifier to introduce outdoor air into the indoor space through the duct:

receiving (103, 105) CO from within the indoor space₂A series of readings of a sensor, each of the readings being indicative of CO within the indoor space₂Horizontal;

determining (107) the CO within the indoor space from the received series of readings₂A rate of decrease of the level; and is

From the CO in the indoor space₂The determined rate of decrease of the level determines (109) a state of the particulate filter.

14. The method (100) according to claim 13, wherein the CO is removed from within the indoor space (1)₂The determined rate of decrease of the level determining the state of the particulate filter (63) comprises: comparing the CO in the indoor space₂The determined rate of decrease in level and the CO within the indoor space₂The horizontal baseline decreases the rate.

15. The method (100) of claim 14, further comprising predicting at least one of the particulate filter remaining life and particulate filter remaining capacity based on the determined status.