Method for operating a vehicle cabin air filter system, use of a filter element, electronic control unit, and cabin air filter system
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-02-08
- Publication Date
- 2026-03-10
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a method of operating a cabin air filter system for a vehicle, the cabin air filter system comprising an air filter device for filtering an air flow entering a passenger compartment, the air flow being made up of fresh air from outside the passenger compartment and recirculated air from inside the passenger compartment, the magnitude of the air flow passing through the air filter device being adjustable, and the ratio of fresh air to recirculated air in the air flow passing through the air filter device being adjustable. [Background technology]
[0002] Such a cabin air filter system is known from WO 2018 / 224299. The system according to WO 2018 / 224299 comprises three filter elements, some of which can be selectively bypassed. Furthermore, the ratio of fresh air to recirculated air is adjustable.
[0003] In general, the use of multiple filter elements can significantly improve the air quality inside the vehicle cabin, especially in highly polluted environments. The use of a larger amount of recirculated air can increase the air quality inside the vehicle cabin. Additionally, selectively bypassing some of the filter elements can extend the life of the filter elements, especially in less polluted environments. Additionally, bypassing some of the filter elements can reduce the energy consumption of the cabin air filter system.
[0004] From EP 1 985 351 A1 an air filter device is known with a filter unit which comprises a filter housing and a filter insert with a filter frame and a filter element. The filter element is provided with a transponder and a reading device for reading the transponder is arranged in the filter unit or outside the filter unit. The data can relate to the type, performance data or technical data of the filter unit. Similar systems are known from WO 2018 / 031403 and DE 202015001147 A1, which comprise an RFID reader and an air filter that has an RFID tag. Information obtained from the RFID tag can be used to determine the remaining service life of the air filter.
[0005] US 2004 / 0065204 describes an air quality monitor for an enclosed cab of an agricultural tractor used to tow or carry a spraying implement for treating crops with substances that may be toxic or harmful to humans. A signal from a pollutant sensor is sent to a control device, which compares the sensed air pollution in the cab over time with values from a performance map representing the expected performance of the cab's air circulation system under normal conditions. If the sensed pollution level is higher than the performance map value, a fault warning is issued to the driver. The blower of the air circulation system can increase its speed to pressurize the cab, preventing the ingress of polluted air through small openings such as the cab seal. The air filters used are coded and recognized by the control device. The control device records the time of use of the filter and issues a warning to the driver when the time of use exceeds a time value stored in association with a particular filter.
[0006] SUMMARY OF THE PRESENT EMBODIMENT It is an object of the present invention to improve the air quality focused operation of cabin air filtration systems.
[0007] This is achieved by a method for operating a cabin air filter system of a vehicle according to claim 1, an electronic control unit for a cabin air filter system of a vehicle according to claim 17, a cabin air filter system according to claim 20 and the use of a filter element according to claim 22. Advantageous embodiments are set out in the dependent claims and in the description. Summary of the Invention
[0008] According to the present invention there is provided a method of operating a cabin air filtration system in a vehicle, for example the vehicle being a car, van or bus.
[0009] The cabin air filter system includes an air filter device that filters the airflow entering the vehicle cabin. The airflow passing through the air filter device is composed of fresh air from outside the vehicle cabin and recirculated air from inside the vehicle cabin. In other words, the fresh air from outside the vehicle cabin and the recirculated air from inside the vehicle cabin are filtered by the air filter device and blown out (returned) into the vehicle cabin. The air filter device includes at least one air filter element.
[0010] The magnitude of the air flow through the air filter device can be adjusted. For this purpose, a blower device can be employed. The magnitude of the air flow refers to the amount of fresh and recirculated air filtered by the air filter device and can be measured as volume or mass per time.
[0011] The ratio of fresh air to recirculated air in the airflow through the air filter device is adjustable. As mentioned above, the airflow through the air filter device is composed of fresh air and recirculated air. The ratio of these two components can be adjusted to only fresh air, only recirculated air, or any ratio in between. Adjustment of the recirculation ratio of fresh air to recirculated air can be made continuously. For this purpose, a flow ratio adjustment device can be employed.
[0012] The air filter device includes at least one filter element. Airflow through the air filter device is directed through the filter element or at least one of the filter elements to remove contaminants such as particles. The filter element includes a storage means. The storage means may be attached to the filter media, end plate, or frame of the filter element. The storage means stores data including information characterizing the filter element.
[0013] The storage means may be an RFID tag, an NFC tag or a graphic code such as a barcode or a QR code. The filter housing of the cabin air filter system may be equipped with a reader for the storage means.
[0014] In step A) of the method, data is obtained from the filter element, comprising information characterizing the filter element. This information allows the type of the filter element to be identified. To this end, the information may comprise an identifier corresponding to a particular type or to a number of similar types of filter elements. The information may comprise a serial number.
[0015] In step B) of the method, for a filter element identified by the information obtained in step A), At least one characteristic of the filter element, the characteristic including information regarding the filtration efficiency of the filter element; a magnitude of airflow through the air filter device; and The recirculation ratio of fresh air to recirculated air; air quality data indicative of air quality inside and / or outside the vehicle cabin; System information is provided that correlates air quality information that characterizes the air quality within the vehicle cabin.
[0016] The system information may be obtained from experiments and / or simulations. The system information may be provided for each pollutant. That is, for each different pollutant, such as particles of different size ranges and / or harmful gases, the system information may include respective relationships of the aforementioned values. The system information describes in particular the functional interdependencies of the associated cabin air filter system. In particular, the filtering efficiency may represent the amount of a particular pollutant that is retained in the filter element, i.e., removed from the air flow through the air filter device, in a given operating state of the cabin air filter system. The air quality information provided in the system information depends on the variables: the magnitude of the air flow through the air filter device, the recirculation ratio of fresh air and recirculated air, and the air characteristic data. The information on the air quality may be the concentration of one or more pollutants in the air in the vehicle cabin. The information on the air quality may be an aggregated air quality index. The air quality index is usually calculated using a formula that combines the amounts of different pollutants, such as, for example, the number of PM1, PM2.5, PM10, NO2, O3, fine particles and ultrafine particles. The air quality index is based on, for example, the US-EPA 2016 standard.
[0017] In step B), the system information may be obtained from a storage means, i.e. the storage means of the filter element provides the system information. This ensures that system information suitable for the filter element is used. In this case, the information characterizing the filter element may be the system information, i.e. the filter element may be characterized by the system information provided in its storage means.
[0018] Alternatively, in step B) the system information may be obtained from an internal storage device of the electronic control unit of the cabin air filter system or from an external database. This allows the use of storage means with limited storage capacity. In the internal storage device of the electronic control unit, the system information may be provided independently of an internet connection or the like. Obtaining the system information from an external database, such as a cloud storage, makes it easier to update the system information.
[0019] In step C) of the method, current air quality data indicative of air quality inside and / or outside the vehicle cabin is obtained, the current air quality data being used as input for evaluating system information in step D).
[0020] The air quality data may be obtained from at least one air quality sensor of the cabin air filter system, which may in particular comprise an internal air quality sensor and / or an external air quality sensor, allowing for particularly accurate air quality data to be obtained.
[0021] Alternatively or additionally, the (external) air quality data may be obtained from an environmental pollution measurement service. This variant allows reducing the hardware costs for vehicles equipped with cabin air filter systems.
[0022] In step D) of the method, air quality information characterizing the air quality in the vehicle cabin is determined from the system information for the current air flow magnitude, the current recirculation ratio of fresh air and recirculated air and the current air characteristic data. The information about the air quality in the vehicle cabin can be used to control the operation of the cabin air filter system. The determined air quality information characterizing the air quality in the vehicle cabin is in particular current air quality information characterizing the current or instantaneous air quality in the vehicle cabin.
[0023] As used herein, associated data may refer to data that is functionally related. For example, at least one characteristic of an air filter device (e.g., air quality information data points) may be correlated with a particular airflow magnitude, fresh air to recirculated air ratio, and air characteristic data. Such multiple data points may be associated, for example, in a database, matrix, multi-dimensional array, map, graph, or combination thereof.
[0024] The providing, obtaining, and / or determining may each be performed by electronic control circuitry including a computing system, for example, a processor, a server, and / or a cloud.
[0025] Alternatively or additionally, a user of the vehicle may be informed of information regarding the air quality in the vehicle cabin, in particular a comparison of the information regarding the air quality in the vehicle cabin with a predefined target value, so that the user is aware of the current effectiveness of the cabin air filter system, the target value being set according to the user's personal preferences.
[0026] The information about the air quality in the vehicle cabin may be compared with target values, for example different target values for different pollutants, in particular different target values for different size ranges of particles and / or harmful gases. The target values may be dependent on the geographic location of the vehicle and / or on user input. The results of the comparison may be used, for example, to control the operation of the cabin air filter system so as to adhere to the target values while minimizing the energy consumption of the cabin air filter system.
[0027] In particular, the recirculation ratio of fresh air to recirculated air can be adjusted based on the comparison. In particular, the comparison can be performed at a predetermined time interval and the recirculation ratio of fresh air to recirculated air can be adjusted accordingly, thereby ensuring that the operation of the cabin air filtration system is always close to optimal. The time interval is selected such that the relevant input parameters do not typically change excessively between two successive evaluations. For example, the time interval can be greater than or equal to 0.5 seconds and / or less than or equal to 10 seconds. In particular, the time interval is 1 second.
[0028] Operation of the cabin air filter system at a recirculation ratio responsive to the comparison result may be interrupted by periods of operation of the cabin air filter system at an air recirculation ratio provided for a higher priority strategy, particularly defogging, defrosting, speed ventilation, or energy conservation.
[0029] According to various embodiments, an air filter device includes: at least one basic filter element for filtering fresh air and / or recirculated air; and at least one HEPA filter element and / or ambient air filter element for filtering the fresh air.
[0030] The HEPA filter element can particularly improve the air quality in the vehicle cabin. The ambient air filter element can protect the HEPA filter element from larger particles and extend its life. Fresh air from the outside can be selectively introduced to pass or bypass the HEPA filter element and / or the ambient air filter element. Typically, the ambient air filter element is arranged upstream of the HEPA filter element. The basic filter element and / or the ambient air filter element may contain at least one adsorbent, in particular activated carbon. The adsorbent can remove harmful gases and odors from the filtered air. Activated carbon is particularly efficient in this respect.
[0031] Depending on the comparison of the information about the air quality in the vehicle cabin with at least one target value, the fresh air flow from outside may be configured to pass through or bypass the HEPA filter element and / or the ambient air filter element. In this way, the HEPA filter element and / or the ambient air filter element can be used only as necessary to meet the air quality target value. Bypassing these filter elements as much as possible can increase the life of the filter elements and reduce energy consumption.
[0032] According to various embodiments, at least one characteristic of the air filter device is: Efficiency curve of the filter element's filter media; The type of filter material, The pressure drop across the filter element as a function of the magnitude of the airflow through the air filter device, and / or It further includes information regarding the contaminant storage capacity of the filter element, in particular the dust storage capacity.
[0033] Efficiency curves may be given for each pollutant, in particular for different size ranges of particles and / or different concentrations of harmful gases. If the air filter device comprises several filter elements, an efficiency curve may be given for the filter medium of each filter element. The type of filter medium may specify whether the air filter medium contains sorbents such as nanofibers and / or activated carbon, and may also specify the HEPA class of the filter medium. The pressure loss may be given as a function of the (expected) dust load of the filter medium. This additional information can be used for a particularly precise control of the cabin air filter system.
[0034] The system information comprises a multi-dimensional data array with the air quality information as an output value. Other parameters of the data array (e.g., the magnitude of airflow through the air filter device, recirculation ratio, air characteristic data) are used as input parameters, i.e., the data array is evaluated against the current values of these parameters. In this way, the system information can be easily established and evaluated. Typically, the data array is stored in the electronic control unit of the cabin air filter system. The data array can be represented in the form of a map or a characteristic diagram.
[0035] According to various embodiments, an interpolation method can be used to determine air quality information from the multi-dimensional data array, allowing efficient and accurate evaluation of system information when input values (e.g., airflow magnitude, recirculation ratio, air characteristic data) deviate from the values for which the data array was created.
[0036] In an advantageous variant of the method, the remaining life of the filter element is determined, which allows the filter element to be replaced in good time while making high use of its filtering capacity. For this purpose, the pollutant accumulation capacity of the filter element and the previous operating time may be taken into account. According to various embodiments, the measurements of an air quality sensor of the cabin air filter system, in particular an external air quality sensor, are taken into account to determine the remaining life. The remaining life may be communicated to the user of the vehicle.
[0037] In a preferred variant of the method, the system information provided in step B) further relates the vehicle speed to the air quality information, and the current vehicle speed is taken into account in step D) in order to determine information regarding the air quality in the vehicle cabin, thereby taking into account the influence of air entering the vehicle cabin from the outside, unfiltered, through seals of openings (such as doors and windows), wires, hoses, etc.
[0038] The system information may take into account aging of the vehicle and / or aging of the filter elements of the air filter device. Aging may lead to increased leakage from the outside that bypasses the air filter device and / or a decrease in the filtering efficiency of the air filter device. By identifying such effects in advance and reflecting them in the system information, an optimal operating condition of the cabin air filter system can be ensured even after degradation of the vehicle and / or the air filter device.
[0039] According to various embodiments, step A) may be repeated each time the vehicle is started and step B) may be repeated at least if the information obtained in a repeated step A) differs from the information obtained in a previous step A). In particular, step B) may be repeated each time the vehicle is started. This variant of the method allows the system information to be always up to date. In particular, if a filter element is replaced with a different type of filter element than the one previously installed, this is recognized and taken into account by obtaining the corresponding system information.
[0040] The method may include determining that the information obtained in step A) differs from information obtained in a previous step A), and repeating step B).
[0041] In an advantageous variant of the method, after step A), it is ascertained whether the filter element is suitable for the cabin air filter system, If the filter element is suitable, steps B) to D) are performed, If the filter element is not suitable, the cabin air filter system will operate in emergency mode and the vehicle user will be notified that the filter element is not suitable.
[0042] The notification may prompt the user to replace the improper filter element with a suitable filter element. The notification may be on the vehicle's display and / or via the user's smartphone app. A link to purchase the suitable filter element online may be provided with the notification.
[0043] In emergency mode, generally no information regarding the air quality inside the vehicle cabin or the remaining life span is determined, and therefore this information cannot be communicated to the user.
[0044] If the air filter device comprises a basic filter element and further filter elements, such as a HEPA filter element and / or an ambient air filter element, in emergency mode the airflow can be directed through all these filter elements, thereby providing the best air quality in the vehicle cabin. Alternatively, in emergency mode the airflow can be directed only through the basic filter element and bypassing all other filter elements, thereby reducing energy consumption and preserving the life of other filter elements, such as the expensive HEPA filter element.
[0045] The invention further relates to the use of a filter element in a cabin air filter system of a vehicle according to the invention, the cabin air filter system comprising an air filter device for filtering an air flow entering the passenger compartment, the air flow being composed of fresh air from outside the passenger compartment and recirculated air from inside the passenger compartment, the size of the air flow through the air filter device being adjustable and the ratio of fresh air to recirculated air in the air flow through the air filter device being adjustable. According to the invention, the filter element comprises a storage means, the storage means comprising system information of the filter element, the system information comprising: At least one characteristic of the filter element, the characteristic including information regarding the filtration efficiency of the filter element; a magnitude of airflow through the air filter device; and The recirculation ratio of fresh air to recirculated air; air quality data indicative of air quality inside and / or outside the vehicle cabin; and air quality information that characterizes the air quality inside the vehicle cabin.
[0046] In other words, the system information used in the above-mentioned method according to the invention is provided by the filter element. The execution of the method is facilitated by the fact that the system information is stored in a storage means of the filter element. In particular, the filter element allows to retrieve the system information from the storage means in step B) of the method. This ensures that system information suitable for the filter element is used.
[0047] According to various embodiments, at least one characteristic of the air filter element is: Efficiency curve of the filter element's filter media; The type of filter material, The pressure drop across the filter element as a function of the magnitude of the airflow through the air filter device, and / or It further includes information regarding the contaminant storage capacity of the filter element, in particular the dust storage capacity.
[0048] Efficiency curves may be given for each pollutant, in particular for different size ranges of particles and / or different concentrations of harmful gases. If the air filter device comprises several filter elements, an efficiency curve may be given for the filter medium of each filter element. The type of filter medium may specify whether the air filter medium contains sorbents such as nanofibers and / or activated carbon, and may also specify the HEPA class of the filter medium. The pressure loss may be given as a function of the (expected) dust load of the filter medium. This additional information can be used for a particularly precise control of the cabin air filter system.
[0049] The storage means may be an RFID tag, an NFC tag or a graphic code, in particular a barcode or a QR code. Such storage means are cheap and easy to read.
[0050] Furthermore, the present invention relates to an electronic control unit for a cabin air filter system of a vehicle, the cabin air filter system comprising an air filter device for filtering an air flow entering the passenger compartment and consisting of fresh air from outside the passenger compartment and recirculated air from inside the passenger compartment, the magnitude of the air flow passing through the air filter device being adjustable and the ratio of fresh air and recirculated air in the air flow passing through the air filter device being adjustable, the air filter device comprising at least one filter element having memory means.
[0051] The electronic control unit is configured to obtain current air quality data indicative of air quality inside and / or outside the vehicle cabin. The electronic control unit is further configured to determine information regarding the air quality inside the vehicle cabin from the system information in response to the current airflow magnitude, the current recirculation ratio of fresh air to recirculated air, and the current air quality data. The system information includes: At least one characteristic of the filter element, the characteristic including information regarding the filtration efficiency of the filter element; a magnitude of airflow through the air filter device; and The recirculation ratio of fresh air to recirculated air; air quality data indicative of air quality inside and / or outside the vehicle cabin; and air quality information that characterizes the air quality inside the vehicle cabin.
[0052] In other words, the electronic control unit is configured to execute steps C) and D) of the above-mentioned method according to the invention. The control unit allows for convenient and efficient execution of the method according to the invention.
[0053] In a first embodiment, the electronic control unit is configured to obtain the system information. For example, the electronic control unit may be configured to obtain the system information from a storage means of the filter element, particularly if the filter element is a filter element according to the present invention as described above. Alternatively, the electronic control unit may be configured to obtain the system information from an external database, such as a cloud storage.
[0054] In a second embodiment, the electronic control unit comprises system information. In particular, the system information may be stored in an internal storage device of the electronic control unit. Different sets of system information may be provided in the internal storage device for different suitable filter elements.
[0055] The present invention also provides a cabin air filter system, comprising: an air filter device for filtering an air flow that flows into a vehicle cabin and is made up of fresh air from outside the cabin and recirculated air from inside the cabin; a blower for adjusting the magnitude of airflow through the air filter device; a flow ratio adjusting device for adjusting the ratio of fresh air to recirculated air in the airflow through the air filter device; a filter element having storage means for storing information characterizing the filter element; a reader for the storage means; The present invention also relates to a cabin air filter system comprising an electronic control unit as described above.
[0056] This cabin air filter can be used to carry out the method according to the invention.
[0057] The storage means may be an RFID tag, an NFC tag or a graphic code such as a barcode or a QR code. The reading device may be an RFID reader, an NFC reader or a graphic code reader, in particular a barcode reader or a QR code reader. Typically, the filter element is mounted in a filter housing of the air filter device, and the reading device may be mounted in the filter housing. Preferably, the filter element is a filter element according to the invention as described above, i.e. the system information may be contained in the storage means.
[0058] Other advantages and features of the invention will be understood from the following description of the embodiments of the invention, with reference to the drawings showing important details, and from the claims. The individual features as mentioned above or below may be implemented separately or in any useful combination in the variants of the invention. [Brief description of the drawings]
[0059] [Figure 1] 1 is a schematic diagram showing a vehicle having a cabin air filter system with a basic filter element, a HEPA filter element and an ambient air filter element, with memory means for storing information about the respective filter elements, in accordance with the present invention, system information about the installed filter elements is used to determine information about the air quality in the vehicle interior. [Diagram 2] FIG. 2 is a schematic diagram of the vehicle of FIG. 1 showing fresh air passing through the ambient air filter element and the basic filter element, bypassing the HEPA filter element. [Diagram 3] 2 is a schematic flow chart of a method of operating a cabin air filtration system according to the present invention, where system information is obtained from a storage means of a filter element; [Figure 4] 2 is a schematic flow chart of a method of operating a cabin air filtration system in accordance with the present invention, where system information is obtained from an external database. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0060] 1 shows a vehicle 10. The vehicle includes a cabin air filtration system 12. The interior of the vehicle 10 defines a passenger compartment 14. Users 16, 18 of the vehicle 10 are seated in the passenger compartment 14.
[0061] The cabin air filtration system 12 includes an air filtration device 20. A total inflow 22 of fresh air from an external environment 24 enters the vehicle interior as a filtered inflow 26 that passes through the air filtration device 20 and an unfiltered inflow 28 that bypasses the air filtration device 20. The magnitude of the unfiltered inflow depends, among other things, on the vehicle speed.
[0062] Air from within the passenger compartment 14 is recirculated through the air filter arrangement 20 in a recirculated air flow 30. A flow ratio adjustment device 32 is provided for adjusting the ratio of the recirculated air flow 30 to the filtered inflow 26. The flow ratio adjustment device 32 is shown here diagrammatically with movable flaps 34, 36.
[0063] The filtered inflow 26 and the recirculated air flow 30 together constitute a filtered air flow 38 passing through the air filter apparatus 20. A blower 40 is provided to regulate the magnitude of the air flow 38 passing through the air filter apparatus 20. The magnitude may be given, for example, as a volume or mass of air per time. The magnitude of the air flow 38 may be measured by a flow meter (not shown).
[0064] Alternatively, the magnitude of the airflow may be estimated. To this end, the voltage and current applied to the blower 40 may be measured. Additionally, the temperature of the air in the external environment 24 may be measured. The density of the external air may be measured or calculated from the temperature. Similarly, the temperature and density of the air within the passenger compartment 14 may be measured and / or calculated. Using this data set, the volumetric and / or mass flow rates through the blower 40 may be determined.
[0065] Air from within the vehicle interior 14 can be allowed to flow out of the vehicle interior through one or more pressure reduction outlets 41. This can prevent the pressure in the vehicle interior 14 from increasing excessively, especially when driving at high speeds. Furthermore, by reducing the pressure in the vehicle interior 14, the energy consumption of the blower 40 for blowing a sufficient amount of fresh air into the vehicle interior 14 can be reduced.
[0066] In the illustrated embodiment, the air filter device 20 includes a base filter element 42, a HEPA filter element 44, and an ambient air filter element 46. The base filter element 42 and the ambient air filter element 46 may include a sorbent, such as activated carbon. Here, the recirculated air flow 30 passes only through the base filter element 42. The filtered inflow 26 may pass through the ambient air filter element 46, the HEPA filter element 44, and the base filter element 42 in succession.
[0067] A bypass function for the external filtered inflow 26 may also be provided with respect to the ambient air filter element 46 or the HEPA filter element 44. As shown diagrammatically in FIG. 2, the filtered inflow may, for example, bypass the HEPA filter element 44 and pass through the ambient air filter element 46 and the basic filter element 42.
[0068] At least one of the filter elements, typically the basic filter element 42 and preferably the HEPA filter element 44 and the ambient air filter element 46 (respectively), comprises a storage means 48. The storage means 48 may be an RFID chip attached to the frame of the respective filter element 42, 44, 46.
[0069] The air filter device 20 comprises at least one reading device 50 for reading the information stored in the memory means 48 of the filter elements 42, 44, 46. Here, a separate reading device 50 for each of the filter elements 42, 44, 46 is mounted on the housing of the air filter device 20. In the illustrated embodiment, the reading devices 50 are each RFID readers.
[0070] The cabin air filter system 12 comprises an electronic control unit 52. The electronic control unit 52 is configured to operate the cabin air filter system 12 according to the invention. The electronic control unit 52 evaluates the information read from the storage means 48 by the reading device 50. Furthermore, the electronic control unit 52 is configured to control the magnitude of the air flow 38 through the air filter device 20 and the recirculation ratio, i.e. the magnitude of the recirculated air flow 30 / the magnitude of the filtered inflow 26.
[0071] FIG. 3 illustrates a flow chart of a method of operating the cabin air filtration system 12 in accordance with the present invention.
[0072] In step 102, data is obtained comprising information characterizing the filter element or elements 42, 44, 46, respectively. For this purpose, the contents of the storage means 48 are read by the reading device 50. Step 102 can be performed each time the vehicle 10 is started.
[0073] In step 104, it is determined whether the installed filter elements 42, 44, 46 are suitable for the cabin air filtration system 12. This may be determined based on the serial number and / or part number retrieved from the memory means 48.
[0074] If the filter element or at least one of the filter elements 42, 44, 46 is not suitable, the electronic control unit 52 can inform the driver 16 via the input / output device 54, e.g. a touch screen, in step 106. Furthermore, the electronic control unit 52 can switch to an emergency mode in step 108. In a first variant of the emergency mode, the HEPA filter element 44 is always active in order to maintain the best air quality in the passenger compartment 14. In another variant of the emergency mode, the HEPA filter element 44 is always bypassed in order to reduce energy consumption and to extend the life of the HEPA filter element 44.
[0075] If the filter elements 42, 44, 46 are suitable, system information is considered for the cabin air filter system 12 with the installed filter elements 42, 44, 46. As shown in Figure 3, the system information may be obtained from the storage means 48 via the reading device 50 in step 110a.
[0076] 4, the system information may be retrieved from an external database, such as cloud storage, in step 110b. The information retrieved in step 102 is used to identify the installed filter elements 42, 44, 46 and retrieve the corresponding system information. Alternatively, the information retrieved in step 102 may be used to retrieve the system information from the internal storage of the electronic control unit 52.
[0077] Other than the procedure for acquiring system information, there is no difference between the operating methods shown in Figures 3 and 4.
[0078] System information is at least one characteristic of the filter elements 42, 44, 46, including information regarding the filtration efficiency of the filter elements 42, 44, 46; the magnitude of the airflow 38 through the air filter device 20; and The recirculation ratio of fresh air to recirculated air and air quality data indicative of air quality inside and / or outside the vehicle cabin 14; and air quality information characterizing the air quality within the vehicle cabin 14. At least one characteristic of the filter elements 42, 44, 46 is efficiency curves of the filter media of the filter elements 42, 44, 46; the type of filter media of each of the filter elements 42, 44, 46; the pressure drop across the filter elements 42, 44, 46 as a function of the magnitude of the airflow 38 through the air filter device 20; For example, further information regarding the contaminant storage capacity, in particular the dust storage capacity, of the basic filter element, the HEPA filter element and the ambient air filter element 42, 44, 46, respectively.
[0079] It should be noted that the effect of open windows or sunroofs may be taken into account in the system information.
[0080] In step 112, current air quality data is obtained that is indicative of air quality inside and / or outside the vehicle compartment 14. The air quality data may be obtained from the exterior air quality sensor 56 or the interior air quality sensor 58 of the cabin air filtration system 12. The exterior air quality data may also be obtained from a public pollution measurement service based on the geographic location of the vehicle 10. A GPS antenna 60 may be used to establish the geographic location of the vehicle 10.
[0081] In step 114, data indicative of the current operating conditions of the vehicle 10, and in particular the cabin air filtration system 12, is provided to the electronic control unit 52. This data includes information regarding the interior and / or exterior air quality obtained in step 112, the magnitude of the air flow 38 through the air filtration device 20, the recirculation ratio of fresh air (filtered inflow 26) to recirculated air (recirculated air flow 30), and optionally vehicle speed.
[0082] Based on the data provided in step 114 and the system information obtained in step 110a or 110b, respectively, electronic control unit 52 determines, in step 116, information regarding the air quality within passenger compartment 14. In other words, the performance of cabin air filtration system 12 as described in the system information is evaluated for the current operating conditions to provide an estimate of the air quality that would be achieved within passenger compartment 14 if operation of cabin air filtration system 12 continued with currently set parameters.
[0083] The information regarding the air quality within the passenger compartment 14 may be provided as an aggregate air quality index. At step 118, the information regarding the air quality within the passenger compartment 14 may be communicated to a user 16, 18 of the vehicle 10, for example via the input / output device 54.
[0084] The air quality targets may be predefined or set by a user 16, 18 of the vehicle 10, for example via the input / output device 54. For example, different targets may be predefined for different regions to comply with local legislation or to meet local user requirements.
[0085] In step 120, the information regarding the air quality within the vehicle cabin 14 determined in step 116 is compared to a target value. The results of the comparison may be communicated to a user 16, 18, as in step 118.
[0086] In step 122, at least one operating parameter of the cabin air filtration system 12 may be adjusted based on the comparison. For example, the ratio of fresh air to recirculated air may be changed, particularly if the target value is not met. If the target value is met, a decision may be made to bypass the HEPA filter element 44. If the target value is not met, the HEPA filter element 44 may be utilized.
[0087] The electronic control unit 52 can monitor the age of the installed filter elements 42, 44, 46. Based on the driving conditions (particularly the (outside) air quality, the magnitude of the filtered air flow 38, the recirculation ratio) and system information (particularly the contaminant storage capacity of the filter elements 42, 44, 46), the electronic control unit 52 can determine the remaining life of the filter elements 42, 44, 46 in step 124, which may be communicated to the user 16, 18 of the vehicle 10.
[0088] In summary, the present invention relates to a method of operating a cabin air filtration system (12) comprising an air filtration device (20) for filtering an air flow (38) entering a vehicle interior (14). The air filtration device comprises at least one filter element (42, 44, 46) having a memory means (48).
[0089] The method includes the following steps. A) obtaining data from a storage means of the filter element, the data including information characterizing the filter element; B) for the filter elements identified by the information obtained in step A), At least one characteristic of the filter element, the characteristic including information regarding the filtration efficiency of the filter element; a magnitude of airflow through the air filter device; and a recirculation ratio of fresh air to recirculated air in the airflow through the air filter device; air quality data indicative of air quality inside and / or outside the vehicle cabin; providing system information relating to air quality information characterizing air quality in a vehicle cabin; C) obtaining current air quality data indicative of air quality inside and / or outside the vehicle cabin; D) determining information regarding the air quality in the vehicle cabin from the system information relative to the current airflow magnitude, the current recirculation ratio of fresh air to recirculated air, and the current air characteristic data. [Explanation of symbols]
[0090] Vehicle 10 Cabin Air Filter System 12 Cabin 14 User 16, 18 Air filter device 20 Total fresh air inflow from the external environment 24 22 filtration inflow 26 Unfiltered infiltration 28 Recirculating Air Flow 30 Flow ratio adjustment device 32 Flap 34, 36 Filtered Air Flow 38 Blower 40 Pressure reduction outlet 41 Basic filter element 42 HEPA filter element 44 Ambient air filter element 46 storage means 48 Reading device 50 Electronic control unit 52 I / O device 54 External Air Quality Sensor 56 Vehicle cabin air quality sensor 58 GPS Antenna 60 Obtain information characterizing the filter elements102 Check that the filter elements are suitable104 Notify of inappropriate filter elements 106 Activate emergency mode 108 Acquire system information from storage means 110a Retrieving system information from an external database 110b Get current air quality data112 Provides current driving data114 Determine information about the air quality inside the vehicle cabin116 Notifying users of air quality information118 Compare air quality information with your target value120 Adjusting operating parameters 122 Determine remaining life of filter element 124
Claims
1. A method of operating a cabin air filtration system (12) of a vehicle (10), comprising: The cabin air filter system (12) includes an air filter device (20) for filtering an air flow (38) flowing into a vehicle compartment (14), the air flow being composed of fresh air from outside the vehicle compartment (14) and recirculated air from inside the vehicle compartment (14); The size of the air flow (38) through the air filter device (20) is adjustable; The ratio of fresh air to recirculated air in the air flow (38) through the air filter device (20) is adjustable; The air filter device (20) comprises at least one filter element (42, 44, 46) having a memory means (48), and the method comprises: A) obtaining (102) data from the storage means (48) of the filter element (42, 44, 48) including information characterizing the filter element (42, 44, 48); B) for the filter elements (42, 44, 48) identified by the information obtained in step A), At least one characteristic of the filter element (42, 44, 48) including information regarding the filtration efficiency of the filter element (42, 44, 48); the magnitude of the air flow (38) through the air filter device (20); a recirculation ratio of the fresh air to the recirculated air; air quality data indicative of air quality inside and / or outside the vehicle cabin (14); and air quality information characterizing the air quality within the vehicle cabin (14). C) obtaining (112) current air quality data indicative of air quality inside and / or outside the passenger compartment (14); D) determining (116) air quality information characterizing the air quality within the vehicle cabin (14) from the system information for the current airflow magnitude, the current recirculation ratio of the fresh air to recirculated air, and the current air characteristic data.
2. 2. The method of claim 1, wherein in step B) the system information is obtained from the storage means (110a).
3. 2. The method of claim 1, wherein in step B), the system information is obtained (110b) from an internal storage device or an external database of an electronic control unit of the cabin air filtration system (12).
4. 2. The method according to claim 1, wherein information about the air quality in the passenger compartment (14), in particular the result of a comparison between the information about the air quality in the passenger compartment (14) and a predetermined target value, is output to a user interface for notifying a user (16, 18) of the vehicle (10).
5. 2. The method according to claim 1, wherein the information about the air quality in the vehicle cabin (14) is compared (120) with a target value, preferably a different target value for each pollutant, in particular a different target value for particles of different size ranges and / or harmful gases.
6. 6. The method of claim 5, further comprising adjusting a recirculation ratio of the fresh air to the recirculated air based on the results of the comparison.
7. The air filter device (20) comprises: at least one basic filter element (42) for filtering said fresh air and / or said recirculated air; 10. The method of claim 1, further comprising: at least one HEPA filter element (44) and / or ambient air filter element (46) for filtering the fresh air.
8. The air filter device (20) comprises: at least one basic filter element (42) for filtering said fresh air and / or said recirculated air; at least one HEPA filter element (44) and / or ambient air filter element (46) for filtering the fresh air; 7. The method of claim 5 or 6, wherein depending on the result of the comparison, a fresh air flow from outside passes through or bypasses the HEPA filter element (44) and / or the ambient air filter element (46).
9. 2. The method of claim 1, wherein in step C), the air quality data is obtained from at least one air quality sensor (56, 58) of the cabin air filtration system (12).
10. 2. The method of claim 1, wherein in step C), the air quality data is obtained from an environmental pollution measurement service.
11. The at least one characteristic of the filter elements (42, 44, 46) is efficiency curves of the filter media of said filter elements (42, 44, 46); The type of the filter material; the pressure loss across the filter elements (42, 44, 46) as a function of the magnitude of the air flow (38) through the air filter device (20); and / or 2. The method of claim 1, further comprising information about the contaminant storage capacity, in particular the dust storage capacity, of the filter elements (42, 44, 46).
12. The method of claim 1 , wherein the system information comprises a multi-dimensional data array having the air quality information as an output value.
13. The method of claim 1, further comprising determining a remaining life of the filter elements (42, 44, 46).
14. 2. The method of claim 1, wherein the system information provided in step B) further relates vehicle speed to the air quality information, and wherein the current vehicle speed is taken into account in step D) to determine information regarding the air quality in the passenger compartment (14).
15. 2. The method of claim 1, wherein step A) is repeated each time the vehicle (10) is started, and step B) is repeated at least if the information obtained in a repeated step A) differs from the information obtained in a previous step A).
16. After step A), it is determined whether the filter element (42, 44, 46) is suitable for the cabin air filter system (12), in particular: If the filter element (42, 44, 46) is suitable, carry out steps B) to D), and / or 2. The method of claim 1, further comprising: operating the cabin air filter system in an emergency mode if the filter element is not suitable; and / or notifying a user of the vehicle that the filter element is not suitable.
17. An electronic control unit (52) for a cabin air filtration system (12) of a vehicle (10), comprising: The cabin air filter system (12) includes an air filter device (20) for filtering an air flow (38) flowing into a vehicle compartment (14), the air flow being composed of fresh air from outside the vehicle compartment (14) and recirculated air from inside the vehicle compartment (14); The size of the air flow (38) through the air filter device (20) is adjustable; The ratio of fresh air to recirculated air in the air flow (38) through the air filter device (20) is adjustable; The air filter device (20) comprises at least one filter element (42, 44, 46) having a memory means (48); the electronic control unit (52) is configured to obtain current air quality data indicative of air quality inside and / or outside the vehicle compartment (14); The electronic control unit (52) is configured to determine information regarding the air quality in the passenger compartment (14) from system information relative to a current magnitude of the air flow (38), a current recirculation ratio of the fresh air to the recirculated air, and the current air quality data, the system information comprising: At least one characteristic of the filter elements (42, 44, 46) including information regarding the filtration efficiency of the filter elements (42, 44, 46); the magnitude of the air flow (38) through the air filter device (20); a recirculation ratio of the fresh air to the recirculated air; air quality data indicative of air quality inside and / or outside the vehicle cabin (14); and air quality information characterizing the air quality within the vehicle cabin.
18. 18. The electronic control unit (52) of claim 17, wherein the electronic control unit (52) is further configured to retrieve the system information from the storage means (48) or an external database.
19. 20. The electronic control unit (52) of claim 18, wherein the electronic control unit (52) comprises the system information.
20. A cabin air filter system (12), comprising: an air filter device (20) for filtering an air flow flowing into a passenger compartment (14) of a vehicle (10), the air flow comprising fresh air from outside the passenger compartment (14) and recirculated air from inside the passenger compartment (14); a blower (40) for adjusting the size of the air flow (38) through the air filter device (20); a flow ratio adjusting device (32) for adjusting the ratio of fresh air to recirculated air in the air flow (38) passing through the air filter device (20); filter elements (42, 44, 46) having storage means (48) for storing information characterizing the filter elements (42, 44, 46); A cabin air filter system (12) comprising an electronic control unit (52) according to any one of claims 17 to 19.
21. 21. The cabin air filter system (12) of claim 20, further comprising a reader (50) for the storage means (48), the reader (50) being selected from the group consisting of a reader installed within the air filter device (20) and a portable reader.
22. 21. Use of a filter element (42, 44, 46) in a cabin air filter system (12) of a vehicle (10) according to claim 20, comprising: The filter elements (42, 44, 46) have storage means (48), the storage means (48) containing system information for the filter elements (42, 44, 46), the system information comprising: At least one characteristic of the filter elements (42, 44, 46) including information regarding the filtration efficiency of the filter elements (42, 44, 46); the magnitude of the air flow (38) through the air filter device (20); a recirculation ratio of the fresh air to the recirculated air; air quality data indicative of air quality inside and / or outside the vehicle cabin (14); and air quality information characterizing the air quality within the vehicle cabin (14).
23. The at least one characteristic of the filter elements (42, 44, 46) is efficiency curves of the filter media of said filter elements (42, 44, 46); The type of the filter material; the pressure loss across the filter elements (42, 44, 46) as a function of the magnitude of the air flow (38) through the air filter device (20); and / or Use of a filter element (42, 44, 46) according to claim 22, further comprising information about the pollutant storage capacity, in particular the dust storage capacity, of said filter element (42, 44, 46).
24. Use of a filter element (42, 44, 46) according to claim 22, wherein said storage means (48) is an RFID tag, an NFC tag or a graphic code, in particular a barcode or a QR code.