Extractor hood and method for operating an extractor hood

Description

[0001] The invention relates to a method for operating a fume hood according to the preamble of claim 1, and to such a fume hood according to claim 9.

[0002] Both private and commercial kitchens now commonly use extractor hoods, also known as range hoods. An extractor hood is a device for extracting and, usually, filtering the cooking fumes produced during cooking. Such a device typically consists of a housing containing a grease filter, such as a disposable non-woven mat or a washable metal filter. The extractor hood also has a fan to draw air containing the fumes from the cooktop into the hood and pass it through the grease filter, thus removing as much grease as possible from the fumes.

[0003] If it is an exhaust air extractor, the cooking fumes are then vented from the building into the surrounding environment, which can lead to a loss of heat energy. Therefore, for energy efficiency reasons, recirculating extractor hoods are now widespread, especially in private households. In these hoods, the fumes are returned to the room, such as the kitchen, after passing through a grease filter, so that no heat energy is lost to the environment. Recirculating extractor hoods typically also have an additional odor filter, for example, in the form of an activated carbon filter, to remove cooking and frying odors from the fumes as completely as possible, which is perceived as more pleasant by the user.

[0004] A disadvantage of recirculating extractor hoods is that the moisture in the cooking fumes cannot be retained by grease or odor filters. This moisture is released back into the kitchen, where it remains. This can not only increase the humidity in the kitchen due to cooking or frying, which is perceived as unpleasant by the user and, in sufficiently cold outdoor temperatures and poorly insulated buildings, can increase the tendency for mold growth, but the efficiency of odor filters, for example, activated carbon filters, can also be reduced by the comparatively high moisture content in the cooking fumes.

[0005] Therefore, it is known to use moisture-adsorbing media in recirculating extractor hoods in the airflow upstream of the activated carbon filter to remove moisture from the fumes as they pass through the hood, thereby reducing or even completely avoiding the disadvantages described above. Examples of moisture adsorbers include zeolites or silica gels, which are also known as siliceous gels or silicic acid gels and are highly hygroscopic, meaning they attract water.

[0006] A moisture-absorbing medium that becomes saturated with moisture must therefore be replaced by the user over time, which can mean both effort and expense for the user. It is also possible to remove the moisture-saturated moisture-absorbing medium from the recirculating extractor hood and dry it, for example, in an oven, in order to reuse it. While this thermal regeneration of a moisture-saturated moisture-absorbing medium can save the cost of a new one, it does require effort from the user. Furthermore, drying in an oven consumes energy and time, during which the recirculating extractor hood cannot be used.

[0007] Alternatively, recirculating exhaust systems are known which can perform the thermal regeneration of a moisture-saturated moisture-adsorbing medium themselves, so that the user does not have to remove it. For example, DE 10 2007 046 044 A1 describes an exhaust system for extracting an airflow from a room, comprising a housing, at least one fan for conveying the airflow through the exhaust system, and a sorption unit arranged in the airflow with a sorbent for absorbing moisture present in the airflow. The exhaust system further includes a regeneration device for regenerating the sorbent, comprising at least one heating element and a heat distribution element.

[0008] A disadvantage of this system is that additional energy is still required for active thermal regeneration. Another disadvantage is that thermal regeneration occurs independently of the kitchen's room climate, meaning that the release of moisture from the saturated moisture-absorbing medium can lead to oversaturation of the kitchen with moisture.

[0009] It is also known to connect cooktops and extractor hoods in such a way that the fan intensity is automatically adjusted in response to the cooktop's operation. This is described, for example, in publication WO 2009 / 127379 A2. For this purpose, both the cooktop and the extractor hood are equipped with a communication module that enables the transmission of device data and operating states via the power grid. For example, during frying, an initially high power setting on the cooktop is typically reduced to a lower power level after the initial searing. However, when such a frying process is detected, the fan intensity is not necessarily reduced, unlike during other cooking processes. This allows for the effective extraction of the fumes produced during frying.

[0010] It is known from publications CH 707 522 A2 and US 2008 141 996 A1 that at least one sensor is provided on the extractor hood and that the power on the cooktop is adjusted via the communication link between the extractor hood and the cooktop depending on the sensor values ​​detected on the extractor hood.

[0011] A cooker hood with a sensor for detecting environmental conditions is also known from publication DE 3 039 246 A1.

[0012] To allow changes to the operating status of a cooker hood, a cooker hood has a control element. This is also revealed in the publications DE 10 2004 034 871 A1 and US 5 690 093 A.

[0013] Setting operating parameters for the extractor hood can also be done using a mobile input device, as taught in the publication DE 10 2011 082 926 A1.

[0014] The invention thus addresses the problem of providing a range hood, in particular a recirculating range hood, of the type described above, such that regeneration of the moisture-adsorbing medium can be carried out more easily and / or quickly and / or without oversaturating the environment, such as a kitchen, with moisture. In particular, regeneration should be possible with less energy consumption and / or dependent on the ambient conditions. Most importantly, thermal regeneration should be avoided. This should preferably occur automatically, i.e., without user intervention. At the very least, an alternative to known regeneration methods for the moisture-adsorbing medium of range hoods, especially recirculating range hoods, should be provided.

[0015] According to the invention, this problem is solved by a method with the features of claim 1 and by a fume extraction device with the features of claim 9. Advantageous embodiments and further developments of the invention are described in the following dependent claims.

[0016] The present invention thus relates to a method for operating a fume extraction device, wherein the fume extraction device can also be referred to as a vapor extraction system. The fume extraction device can be an exhaust air fume extraction device or, preferably, a recirculating air fume extraction device, the latter being where the properties according to the invention are more effectively realized, as will be explained below.

[0017] The extractor hood has a housing which, at least in sections, forms a flow channel for guiding an airflow. The flow channel has an inlet opening, which is designed to face a source of fumes, and an outlet opening, which is designed to face away from the source of fumes. The source of fumes can be, in particular, a cooktop or an oven, where vapors, i.e., steam or vapors, can be generated during operation. The flow channel is therefore designed to capture the fumes via the inlet opening, guide them through it, and release them again via the outlet opening. In the case of an exhaust air extractor hood, this release can occur to an environment outside a building, and in the case of a recirculating extractor hood, it can occur back to the immediate surroundings of the recirculating extractor hood, such as a kitchen.The housing forms at least part of the flow channel, so that the flow channel runs at least partially inside the housing and the inlet and outlet openings break through the housing.

[0018] The extractor hood also includes at least one sorption filter, which is arranged within the airflow channel and designed to absorb moisture from the airflow. The sorption filter can also be referred to as a moisture absorber. Its purpose is to absorb and store moisture from the airflow of the cooking fumes, so that the fumes leave the sorption filter with less moisture than when they entered the sorption filter.

[0019] The exhaust ventilation device according to the invention is characterized in that it is designed without a device for generating heat energy. This makes it possible to regenerate the sorption filter during drying operation with minimal energy expenditure. The exhaust ventilation device uses ambient room air to regenerate the sorption filter over a period longer than the period during which fumes are generated.

[0020] The sorption filter preferably has a particularly high moisture absorption capacity and / or a particularly high moisture release capacity. In other words, the extractor fan is designed to quickly absorb a large amount of moisture from the cooking fumes in humid conditions, such as during cooking, and to release the absorbed moisture easily and quickly in dry conditions, such as outside of a cooking process that generates fumes. The threshold between a dry and a humid condition is preferably in the range of 40 percent to 70 percent relative humidity, preferably based on the humidity within the airflow duct.

[0021] The extractor fan can therefore be operated in two different modes.

[0022] Preferably, the control unit of the extractor hood is designed to switch the fan on at least one predetermined first time and / or switch it off at least one predetermined second time during drying operation. Additionally or alternatively, the control unit of the extractor hood is designed to switch the fan on after a predetermined first time interval and / or switch it off after a predetermined second time interval. This allows the drying of the sorption filter to take place at a time when the user is less disturbed by the operation of the extractor hood and when the ambient air is drier than during or immediately after cooking. This results in high energy efficiency during regeneration and a high level of user comfort.

[0023] Furthermore, this makes it possible to significantly extend the regeneration period compared to the moisture absorption period. This keeps the humidity level in the ambient air at a consistent and lower level compared to a more concentrated regeneration process. This also results in increased comfort and energy efficiency.

[0024] The extractor fan operates in a standard mode during cooking. A significant amount of steam is generated above the cooktop, which is captured by the extractor fan and stored in the sorption filter. In standard mode, the extractor fan can operate at at least one speed and / or power setting. Designs are also possible in which the extractor fan operates at several different speeds and / or power settings during standard mode.

[0025] The extractor fan is usually switched off when not in use. Regeneration of the sorption filter is possible even in this state. A preferred embodiment of the invention provides that the extractor fan is operated in a drying mode when not in use. In this mode, the extractor fan is kept in standby mode and operates at least one drying speed and / or at least one drying capacity. At least one of these drying speeds and / or drying capacities is lower than the lowest of the at least one controlled speed and / or controlled capacity. This allows for particularly effective regeneration of the sorption filter, with low fan noise and / or low fan energy consumption.

[0026] One embodiment provides that in drying operation all drying speeds and / or drying capacities are lower than all control speeds and / or control capacities in normal operation.

[0027] In drying mode, the fan can be operated depending on predefined or stored time sequences and / or depending on recorded sensor values, as described in detail below.

[0028] Such a sorption filter can preferably be created by generating an open-pored, macroporous structure of an activated carbon filter through very high chemical activation, while preserving the hydrophilicity of the raw material, i.e., the wood. This type of sorption filter exhibits a particular tendency to adsorb water vapor at high humidity. Between 70 and 80 percent RH (relative humidity), this activated carbon adsorbs a comparatively large amount of moisture, whereas conventional activated carbons absorb little or no moisture at this level. However, the binding forces on the macroporous surface are simultaneously sufficiently weak to allow the water vapor molecules to detach again as the relative humidity decreases.

[0029] Chemical activation is part of the activated carbon manufacturing process. A mostly uncarbonized, carbon-containing material is first mixed with dehydrating and oxidizing chemicals. These chemicals include, for example, zinc chloride, phosphoric acid, and sulfuric acid. This mixture is then heated, generally at 400–900 °C. The activating agents are subsequently washed out and recovered. Another method is dry distillation, in which the material is heated in an oxygen-free atmosphere, and volatile components are driven off at temperatures around 800 °C. The resulting raw activated carbon is then oxidatively activated at 400–1000 °C with steam or carbon dioxide, and sometimes with air.In the temperature range of 400°C to approximately 600°C, low chemical activation occurs, while in the temperature range of 700°C to 1000°C, high chemical activation takes place.

[0030] In this way, according to the invention, it can be achieved that the sorption filter has sufficient capacity available for moisture binding during each cooking process.

[0031] The sorption filter has a high water absorption capacity (adsorption) and water release capacity (desorption) compared to conventional activated carbon filters, which have low properties in these areas. The difference between high and low adsorption and desorption is particularly evident in a boiling test where, upon evaporating 250 ml of water, the sorption filter adsorbs at least 30 percent more water than a conventional activated carbon filter. According to one embodiment, the sorption filter adsorbs approximately twice the amount of water as a conventional activated carbon filter. Regarding water release, the sorption filter behaves similarly, releasing water over 20 percent faster than a conventional activated carbon filter. According to another embodiment, the sorption filter desorbs the same amount of water approximately twice as fast as a conventional activated carbon filter.

[0032] One embodiment provides that the sorption filter has an adsorption capacity of 0.05 to 0.1 grams of water per gram of sorption filter, preferably approximately 0.065 grams of water per gram of sorption filter.

[0033] One embodiment provides that the sorption filter has a desorption capacity of 0.01 to 0.08 grams of water per gram of sorption filter, preferably approximately 0.03 grams of water per gram of sorption filter.

[0034] According to the present invention, the exhaust ventilation device further comprises at least one fan which is arranged and configured within the flow channel, preferably in the airflow in front of the sorption filter, to generate and / or enhance the airflow, wherein the control unit of the exhaust ventilation device is configured to operate the fan for drying the air of the sorption filter.

[0035] The present invention is based on the idea that, without a fan, the airflow through the flow channel can only be generated, if at all, by the steam itself, which can lead to a comparatively weak airflow and thus also to a comparatively low moisture reduction by the sorption filter. Therefore, the airflow, and thus the effect of the sorption filter, can be increased if the airflow is generated or amplified by a fan.

[0036] However, according to the invention, a fan already present in a range hood can also be used to generate an airflow even when there is no cooking fumes to be supplied to the sorption filter. In other words, the user can, for example, use the fan while cooking to supply the cooking fumes as an airflow to the sorption filter, thereby adding moisture to the filter and removing moisture from the fume-laden airflow. Outside of its use during cooking, however, the fan can, according to the invention, operate automatically—that is, without direct user intervention—to supply a cooking-free airflow to the sorption filter, which is at least partially saturated with moisture, so that moisture can be added to the airflow and thereby removed from the sorption filter. In this way, without additional technical means such as...A heating element enables automatic drying of the sorption filter by air, so that when the extractor fan is next used by the user, e.g. for cooking, a drier sorption filter with higher effectiveness is available than previously known.

[0037] The regeneration of the sorption filter free from heat energy generated by the extractor fan enables a particularly energy-efficient design of the extractor fan.

[0038] According to the invention, user interventions such as replacing or removing and drying the sorption filter are unnecessary. Furthermore, the sorption filter can be regenerated earlier, ensuring consistently high efficiency. This also eliminates the need for additional measures such as using a heating element for thermal regeneration and the associated energy costs. This can make the extractor hood more cost-effective, lighter, and / or more space-saving, thereby reducing operating costs.

[0039] The present invention also relates to a ventilation device, preferably a recirculating ventilation device, with a housing which at least partially forms a flow channel for guiding an airflow, wherein the flow channel has an inlet opening which is designed to be arranged facing a source of fumes, and wherein the flow channel has an outlet opening which is designed to be arranged facing away from the source of fumes, and with at least one sorption filter which is arranged and designed within the flow channel to absorb moisture from the airflow.The exhaust ventilation device is characterized by at least one fan, which is arranged and designed within the flow channel, preferably in the airflow in front of the sorption filter, to generate and / or enhance the airflow, wherein the exhaust ventilation device is designed to operate the fan for air drying of the sorption filter.

[0040] In this way, the advantages of such a fan described above can also be used independently of the sorption filter according to the invention described above.

[0041] According to a further aspect of the present invention, the extractor fan is configured to operate the fan at at least one predetermined time and / or within at least one predetermined period and / or at at least one predetermined time interval and / or for at least one predetermined duration. This enables time-dependent automatic operation.

[0042] The underlying principle of this aspect of the present invention is to release the absorbed moisture back into the environment, preferably over a period of time and / or gradually. Releasing the moisture at a later time than the cooking process can be advantageous to avoid disturbing the user with the fan noise immediately after cooking, and thus presumably during the meal. Extending the release over a period of time, for example up to 23 hours until the next lunch the following day, can be advantageous to avoid placing too much additional moisture in the environment.

[0043] The prevailing air exchange rate in a kitchen, which in modern buildings with forced ventilation is often continuous and uninterrupted, leads to a steadily decreasing humidity after cooking.

[0044] For example, at least one time can be set for the automatic drying of the sorption filter. This could be, for instance, a time at midnight or during working hours on weekdays, such as 9:00 a.m., when the source of fumes, such as the cooking area, is not typically in use, thus preventing any conflict between use and drying of the sorption filter. Multiple such times can also be set to allow for repeated or regular drying, ensuring that a dry sorption filter is available at all times, for example, in the morning, at midday, and in the evening.

[0045] Additionally or alternatively, a period for air-drying the sorption filter can be specified. This could be, for example, at night from 00:00 to 06:00, or during working hours on weekdays, for example, between 09:00 and 11:00. Multiple time periods can also be specified, such as from 00:00 to 06:00, from 09:00 to 11:00, and from 14:00 to 17:00, during which cooking is not typically done.

[0046] Furthermore, according to the invention, a predetermined time interval can be set, e.g., after the last use of the extractor fan by the user, e.g., during cooking, in order to carry out air drying of the sorption filter. For example, after each use of the extractor fan during a cooking process, automatic air drying of the sorption filter can be started after a time interval of, e.g., 60 minutes. Multiple time intervals can also be specified, e.g., to start a second air drying cycle 90 minutes after the cooking process. A periodic repetition of the air drying process can also be specified, so that, e.g., after a cooking process, automatic air drying of the sorption filter can be started several times, e.g., every 60 minutes.

[0047] Furthermore, a duration for automatic air drying of the sorption filter can be additionally or alternatively specified, allowing it to be limited to, for example, 15 minutes. This can be particularly advantageous for recurring, periodic, or regular processes for automatic air drying of the sorption filter, in order to achieve the desired drying without running the fan continuously or for extended periods, which could disturb a user due to noise. Instead, a distributed and gradual return of the stored moisture to the environment can occur, which is significantly less disruptive to the user.

[0048] For example, in a simple case, the air drying of the sorption filter can be achieved by running the fan for 15 minutes every two hours, starting 60 minutes after the cooking process has finished. This can be done for 22 hours, so that 23 hours after the last cooking process, a sorption filter that is as completely dry as possible should be available again.

[0049] A diversified use of the possibilities according to the invention can be achieved, for example, by starting several drying processes of 15 minutes each at 60-minute intervals, e.g., at night between 00:00 and 06:00, when the kitchen is not typically used for cooking on any day of the week, so that a sorption filter that is as completely dry as possible is available in the morning. From then on, for example, after each use, which may vary over the course of a week and especially between weekdays and weekends, further drying processes of 10 minutes each, at 30-minute intervals, can be started, delayed by 60 minutes from the cooking process, in order to carry out a further air drying of the sorption filter only when necessary, but then as quickly as possible, in order to avoid unnecessary energy consumption.

[0050] According to a further aspect of the present invention, the extractor fan is designed such that operation of the fan can be excluded at at least one predetermined time and / or within at least one predetermined period. For example, this can prevent noise from the fan running in the kitchen, e.g., in the afternoon or evening, or all day on weekends, which could be perceived as disturbing by the user.

[0051] According to a further aspect of the present invention, the extractor fan is designed so that a user can specify a predetermined time, period, interval, or duration. This allows the user to adjust the extractor fan according to the invention to their personal needs in order to achieve the desired drying of the sorption filter with the shortest possible operating time and frequency. Preferred and excluded times or periods can also be specified, during which the cooktop is not expected to be used for cooking or during which the fan should not be used to dry the sorption filter. All of this can be specified according to time of day, day of the week, weekdays and weekends, weeks, months, vacation periods, etc.It is also possible to create different settings for multiple users.

[0052] According to a further aspect of the present invention, the exhaust system has at least one external sensor configured to detect the humidity outside the airflow duct. The control unit of the exhaust system is configured to operate the fan based on the humidity outside the airflow duct when the humidity outside the airflow duct falls below a predetermined threshold. By operating the fan based on the humidity outside the airflow duct, it is possible, for example, to ensure that the sorption filter is only dehumidified if the humidity outside the airflow duct is sufficiently low to absorb the moisture released by the sorption filter during dehumidification.In particular, this can prevent excessively high humidity in the environment, which could be perceived as unpleasant by a user.

[0053] The extractor fan is designed so that, during drying operation, it only switches on when the humidity outside the airflow duct falls below a predefined and / or selectable value. The external sensor can be mounted on the extractor fan or its housing to measure the humidity outside the airflow duct. Alternatively, the external sensor can be separate from the extractor fan and positioned at a distance from it. The external sensor can also be an independent device or a component of another device, such as another household appliance, particularly a kitchen appliance, or even a building automation system, which collects humidity data for other purposes and can also provide this data to the extractor fan.In these cases, data transmission of the measured values ​​to the extractor hood can preferably be wireless.

[0054] According to a further aspect of the present invention, the exhaust system has at least one internal sensor, which is arranged and configured within the airflow channel, preferably in the airflow behind the sorption filter, to detect the humidity within the airflow channel. The exhaust system is configured to operate the fan depending on the humidity within the airflow channel. This ensures that the sorption filter is only dried when it has actually stored sufficient moisture to necessitate drying or justify the corresponding energy expenditure for operating the fan. Otherwise, this drying process can be omitted to save energy and avoid noise disturbance to the user. This preferably takes precedence over time-dependent settings for drying the sorption filter.

[0055] According to a further aspect of the present invention, the exhaust system is designed to operate the fan only when the humidity inside the airflow channel is higher than the humidity outside the airflow channel. This allows the automatic drying of the sorption filter to be reliably limited to times when the moisture released by the sorption filter can be safely absorbed by the ambient air, even when the drying process is time-dependent. Furthermore, the fan operation can be automatically terminated when this condition is no longer met, as it can then be assumed that sufficient drying of the sorption filter has been achieved.

[0056] According to a further aspect of the present invention, the exhaust system is designed to automatically adjust the fan's power level. In this way, the drying of the air in the sorption filter can be influenced not only by the duration of the fan's operation but also by its operating intensity. This can increase the drying efficiency and reduce noise pollution for the user.

[0057] Furthermore, this allows for targeted control of the fan's operating noise. For example, a lower power setting can be selected at night to minimize disturbance to the user's sleep. Longer and / or more frequent fan operating cycles can then be chosen to achieve effective and, ideally, the most complete drying of the sorption filter possible. Conversely, during the day, for example, after cooking, a higher power setting can be used to dry the sorption filter as quickly as possible. This can significantly increase both the drying efficiency and user comfort.

[0058] According to a further aspect of the present invention, the control unit of the extractor fan is designed to detect the duration of operation of the fan by a user and / or the setting of a power level of the fan by a user and / or the humidity generated, and then to operate the fan automatically depending on the detected operating time and / or the set power level and / or the humidity generated.

[0059] According to the present invention, the control unit of the extractor hood is designed, at least during normal operation, to detect the moisture generated above the cooktop and to store a value for the moisture generated at any given time and / or over time. This makes it possible to adjust the duration and / or intensity of the drying operation depending on the previously determined load of the sorption filter.

[0060] The loading of the sorption filter is determined by one or more measurements from the indoor sensor. According to a preferred embodiment, the loading of the sorption filter is determined by calculating a gradient between the measurements of the indoor and outdoor sensors; in particular, multiple gradients over time are taken into account.

[0061] The loading of the sorption filter is preferably determined during normal operation.

[0062] In this way, the drying of the sorption filter after use of the extractor hood, for example during cooking, can be controlled based on the amount of steam produced. This can be achieved without the need for an internal sensor in the extractor hood, because the extractor hood itself can detect how long and / or at what power level the user operated its fan. From this, it can be deduced how much moisture from the steam was transferred to the sorption filter. Alternatively, the internal sensor can measure the moisture content of the steam over the course of the cooking process, providing information on the approximate amount of moisture transferred to the sorption filter during cooking. These methods can also be combined to improve the accuracy of the results.to improve by calculating an average.

[0063] In any case, the subsequent automatic air drying of the sorption filter can be carried out with a corresponding duration and / or intensity to release precisely the estimated or measured absorbed moisture. This allows the air drying of the sorption filter to be tailored as directly and easily as possible to its use.

[0064] The intensity of the drying process is determined by the number and / or duration of ventilation intervals and / or the fan speed or power during the drying process. The intensity of the drying process can also be understood synonymously as the volume of air moved through the sorption filter during the drying process.

[0065] According to a further aspect of the present invention, the extractor hood also includes an odor filter, which is arranged within the airflow channel, preferably in the airflow downstream of the sorption filter, and is designed to capture odors from the airflow. This allows additional odors to be removed from the cooking fumes, which can be more pleasant for the user, especially in the case of a recirculating extractor hood.

[0066] According to a further aspect of the present invention, the extractor hood also includes a grease filter, which is arranged within the airflow channel and is designed to filter grease from the airflow, wherein the grease filter is preferably arranged in the airflow upstream of the sorption filter, and particularly preferably immediately after the inlet opening of the airflow channel. This allows additional grease to be removed from the fumes, which can be more convenient for the user, especially in the case of a recirculating extractor hood.

[0067] According to a further aspect of the present invention, the sorption filter is designed at least partially, preferably completely, as an activated carbon filter. This allows for the creation of a sorption filter that is as inexpensive and / or simple and / or robust as possible, which can be air-dried as described above.

[0068] The present invention also relates to a sorption filter for use in a fume hood as previously described, with a particularly high moisture absorption capacity and / or with a particularly high moisture release tendency. This allows the creation of a sorption filter with which a fume hood according to the invention can be implemented.

[0069] During drying, the fan of the extractor hood can be switched on and / or off either solely based on a timer or solely on sensor readings. A particularly effective and convenient design of the extractor hood is one in which the fan's activation and / or deactivation is controlled by a combination of timers and sensor data.

[0070] The present invention also relates to a method for operating a fume hood as described above, comprising at least the step of: Automatic operation of the fan for drying the air in the sorption filter.

[0071] This allows a fume extraction device according to the invention to be operated as described above. Further properties and advantages described above can also be implemented as additional process steps within this method.

[0072] Within the scope of the present invention, the expression "in front of" in the airflow is to be understood as meaning that a first component, which is arranged in the airflow in front of a second component, is first through which the airflow flows, i.e., before the second component. Accordingly, the expression "behind" in the airflow is to be understood as meaning that a first component, which is arranged in the airflow behind a second component, is last through which the airflow flows, i.e., after the second component.

[0073] An embodiment of the invention is shown schematically in the drawing and is described in more detail below. It shows Figure 1 is a schematic sectional view of a ventilation device according to the invention.

[0074] The figure above is viewed in Cartesian coordinates. A longitudinal direction X extends across it, which can also be called depth X. Perpendicular to the longitudinal direction X extends a transverse direction (not shown), which can also be called width. Perpendicular to both the longitudinal direction X and the transverse direction extends a vertical direction Z, which can also be called height Z.

[0075] Figure 1 Figure 1 shows a schematic sectional view of a ventilation device 1 according to the invention, which can be used preferably within a kitchen as a recirculating ventilation device 1 and can also be referred to as a recirculating vapor extraction device 1.

[0076] The recirculating air extractor device 1 has a housing 10, which is made of metal and forms or encloses a flow channel 11. For this purpose, the housing 10 has an inlet opening 11a of the flow channel 11 at height Z in the lower area, which forms a vapor shield 12. From the inlet opening 11a, the flow channel 11 extends essentially straight upwards at height Z through the housing 10 to an outlet opening 11b of the flow channel 11 at the upper end of the housing 10. The inlet opening 11a and the outlet opening 11b are the only openings or penetrations of the housing 10, which is otherwise closed, so that an airflow can be guided through the flow channel 11.

[0077] The housing 10 in the lower part of the vapor screen 12 is rectangular in both depth X and width (not shown) and corresponds approximately to the shape of a cooktop located at height Z below it, which serves as the vapor source (not shown). Cooking vapors from the cooktop or the cookware used on it can rise upwards as vapor at height Z and enter the flow channel 11 via the inlet opening 11a. Due to its own heat, the vapor can rise further upwards through the flow channel 11 at height Z and exit the flow channel 11 back into the kitchen via its outlet opening 11b.

[0078] To clean the steam in various ways as it passes through the flow channel 11, a grease filter 15 is arranged inside the housing 10 in the flow channel 11 immediately behind its inlet opening 11a. The airflow passes through this filter, which removes grease from the steam, allowing it to exit through the outlet opening 11b with a reduced grease content. This can improve the air quality in the kitchen for the user.

[0079] For a similar purpose, an odor filter 13 is arranged within the housing 10 in the flow channel 11 near the outlet opening 11b. The airflow passes through this filter, which removes odors from the steam, allowing the steam to exit the outlet opening 11b with a reduced odor content. This, too, can improve the air quality in the kitchen for the user.

[0080] Since the effectiveness of the odor filter 13 can be reduced by the comparatively high humidity of the steam, a sorption filter 14 in the form of an activated carbon filter 14 is arranged in the airflow channel 11 upstream of the odor filter 13. The airflow passes through the steam, allowing it to absorb moisture from the steam. This can improve or maintain the effectiveness of the odor filter 13.

[0081] To direct as much cooking fumes as possible from the cooktop into the recirculating extractor hood 1 and to purify them with regard to their grease content and odors, a fan 16 is arranged within the flow channel 11 between the fume shield 12 and the sorption filter 14, so that the airflow can be increased by operating the fan 16. The fan 16 can be controlled and operated by a control unit (not shown) of the recirculating extractor hood 1. This can be done, for example, by the user via inputs on a control panel (not shown) on the front of the housing 10 in the area of ​​the fume shield 12, at a depth X to the right of the user in the illustration. Figure 1 These actions can be performed facing the direction of the fan. This allows the fan 16 to be switched on and off, and different power levels of the switched-on state to be selected.

[0082] Since the adsorbed moisture from the steam is stored by the sorption filter 14, it will eventually become saturated with moisture, which can cause the sorption filter 14 to gradually lose its effectiveness. This can correspondingly affect the effectiveness of the odor filter 13.

[0083] Therefore, according to the invention, a sorption filter 14 with a particularly high moisture absorption capacity is used, so that a reduction in the effectiveness of the sorption filter 14 can be delayed for as long as possible. At the same time, the sorption filter 14 has a particularly high moisture release tendency, so that comparatively effective drying of the sorption filter 14 can take place. This allows a state of near-dryness of the sorption filter 14 with correspondingly high effectiveness to be restored as quickly as possible.

[0084] This can preferably be achieved by using the fan 16 not only to generate or amplify the airflow of the steam through the flow channel 11 during the cooking process, where the fan 16 is operated manually by the user. According to the invention, outside of the cooking process, the fan 16 is automatically used by the recirculating air extraction system 1 to dry the sorption filter 14. For this purpose, the fan 16 is operated so that ambient air is conveyed or drawn into the flow channel 11 via the inlet opening 11a, flows through the sorption filter 14, and absorbs moisture, which is then released into the environment via the outlet opening 11b.

[0085] In this way, the user can be provided with a consistently dry sorption filter 14 very easily, promptly, and quickly, without additional measures such as a heating element or user intervention, and without any correspondingly good effect. This can have a positive impact on the effectiveness of the odor filter 13.

[0086] Preferably, the automatic air drying of the sorption filter 14 is carried out by measuring the humidity of the ambient air via an external sensor 17 of the recirculating air extractor 1, which is arranged on the outside of its housing 10, after a user has finished manual operation of the recirculating air extractor 1 for cooking. Simultaneously, within the flow channel 11, the humidity in the airflow behind the sorption filter 14 is measured by means of an internal sensor 18 located therein. This measurement can be considered representative of the moisture content of the sorption filter 14, both when the fan 16 is at rest and when the fan 16 is operating outside of a cooking process that generates steam.

[0087] If the internal sensor 18 detects a humidity reading in the flow channel 11 that is higher than the humidity reading of the external sensor 17 in the vicinity of the recirculating air extractor 1, the recirculating air extractor 1 automatically starts the fan 16 to dry the air in the sorption filter 14. The fan 16 is preferably not operated continuously but periodically for a predetermined short period of time.

[0088] During this operation, the two measured values ​​are continuously compared, and the operation of the fan 16 is maintained as long as the measured humidity in the flow channel 11 is higher than the measured humidity in the environment. Only when this condition is no longer met is the operation of the fan 16 automatically stopped by the recirculating air extraction system 1.

[0089] Preferably, information about the moisture saturation of the sorption filter 14, which can be obtained from the previously described comparison of the two moisture measurements, can be displayed, for example, via a display such as an LED display (not shown) on the front of the housing 10 in the area of ​​the vapor screen 12 at depth X to the right of the user in the representation of the Figure 1 The information is displayed facing the user. This allows the user to be informed about the status and effectiveness of the sorption filter 14. This information can also be transmitted to, for example, the cooking station and displayed there. Furthermore, this information can be transferred to a mobile device such as a tablet or smartphone and displayed to the user via an app. Reference numeral list (part of the description)

[0090] Longitudinal direction; Depth; Vertical direction; Height 1 (Recirculating) extractor hood; (Recirculating) vapor extraction 10 Housing 11 Airflow duct 11a Airflow duct inlet 11 11b Airflow duct outlet 11 12 Vapor screen 13 Odor filter 14 Absorption filter; activated carbon filter 15 Grease filter 16 Fan 17 External sensor 18 Internal sensor

Claims

1. Method for operating an extractor hood device (1), wherein the extractor hood device (1) comprises a housing (10) which at least partially forms a flow channel (11) for guiding an air flow, and wherein the flow channel (11) has an inlet opening (11a) which is designed to be arranged facing a vapour source, and wherein the flow channel (11) has an outlet opening (11b) which is designed to be arranged facing away from the vapour source, and at least one sorption filter (14) which is arranged within the flow channel (11) and is designed to absorb moisture from the air flow, and a fan (16) which is arranged within the flow channel (11), preferably in the air flow upstream of the sorption filter (14), and is designed to generate and / or amplify the air flow, and a control unit which is designed to control the fan (16) of the extractor hood device (1), and wherein the extractor hood device (1) is free of a device for generating thermal energy, characterised in that the moisture generated above the cooking hob is detected by the control unit of the extractor hood device (1), at least during normal operation, and stored as a value for the moisture generated momentarily and / or over time, and the extractor hood device (1) is put into a drying operation by the control unit depending on a predetermined point in time which is specified by the user, wherein the control unit operates (100) the fan (16) during the drying operation for a period of time specified by the user; and / or the extractor hood device (1) is put into a drying operation by the control unit depending on a predetermined time interval from the last operation of the extractor hood device (1) by the user, wherein the time interval is specified by the user, and wherein the control unit operates (100) the fan (16) during the drying operation for a period of time specified by the user.

2. Method according to the preceding claim, wherein the fan (16) is operated depending on a detected humidity, which is detected by an external sensor (17) and / or an internal sensor (18), in particular when the ambient air of the extractor hood device is drier than at the time of a cooking process or immediately after a cooking process.

3. Method according to either of the two preceding claims, wherein the moisture generated above the cooking hob is detected by the control unit of the extractor hood device (1), at least during normal operation, and stored as a value for the moisture generated momentarily and / or over time.

4. Method according to any of the preceding claims, wherein the duration and / or intensity of the drying operation depends on the previously determined loading of the sorption filter.

5. Method according to any of the preceding claims, wherein the control unit is designed such that operation of the fan (16) is disabled at at least one predetermined point in time and / or within at least one predetermined period of time.

6. Method according to any of the preceding claims, wherein the control unit is designed such that during a drying operation, the fan (16) is switched on at at least one predetermined first point in time and / or is switched off at at least one predetermined second point in time and / or the fan (16) is switched on after a predetermined first time interval and / or is switched off after a predetermined second time interval.

7. Method according to any of the preceding claims, wherein the extractor hood device (1) is designed so that the predetermined period of time and / or the predetermined time interval is specified by a user.

8. Method according to any of the preceding claims, wherein the control unit is designed such that the fan (16) is operated depending on the humidity outside the flow channel (11) when the humidity outside the flow channel (11) is below a predetermined threshold.

9. Extractor hood device (1), which is provided for detecting the humidity generated above a cooking hob during a cooking process of the cooking hob, which device, during normal operation, absorbs the moisture from the vapours generated above the cooking hob and stores it in the sorption filter, the device comprising a housing (10) which at least partially forms a flow channel (11) for guiding an air flow, wherein the flow channel (11) has an inlet opening (11a) which is designed to be arranged facing a vapour source, and wherein the flow channel (11) has an outlet opening (11b) which is designed to be arranged facing away from the vapour source, and comprising at least one sorption filter (14) which is arranged within the flow channel (11) and designed to absorb moisture from the air flow, and comprising a fan (16) which is arranged within the flow channel (11), preferably in the air flow upstream of the sorption filter (14), and is designed to generate and / or amplify the air flow, and comprising a control unit which is designed to control the fan (16) of the extractor hood device (1) and to operate the extractor hood device (1) during normal operation, wherein the extractor hood device (1) is free of a device for generating thermal energy, characterised in that the control unit is designed to carry out the method according to claim 1, wherein the extraction hood device (1) can be operated during a drying operation, wherein during normal operation, the air flow is higher than during the drying operation.

10. Extractor hood device (1) according to the preceding claim, wherein the sorption filter (14) is at least partially, preferably completely, designed as an activated carbon filter (14).

11. Extractor hood device (1) according to either of the two preceding claims, wherein at least one external sensor (17) which is designed to detect the humidity outside the flow channel (11).