Recirculation filter and system with a recirculation filter and a replacement filter element

Abstract

Recirculating air filter (1) for an extractor hood with at least one housing (2) with a closure element (3) and with at least one filter element (4) accommodated in the housing (2), characterized in that the housing (2) can be opened in a resealable manner via the closure element (3) in order to replace the filter element (4) with a replacement filter element (4.1).

Description

[0001] The present invention relates to a recirculating air filter for an extractor hood having at least one housing with a closure element and having at least one filter element accommodated in the housing according to the preamble of claim 1 and to a system having the recirculating air filter according to the invention and having a replacement filter element according to claim 9. DESCRIPTION OF THE PRIOR ART AND BACKGROUND OF THE INVENTION

[0002] To remove fumes (vapours), vapors, dust, or other pollutants, extractor hoods are installed above stoves or cooking areas, or above sources of dust and pollutants, in kitchens or other work spaces, such as commercial ones. These extractor hoods are equipped with filters on suction fans and air ducts. If an air duct is missing, they blow the filtered air back into the work area through one or more outlets. This type of operation is called recirculation mode. However, even hoods that blow air outside via a fan during operation sometimes recirculate some of the extracted air back into the extracted room.

[0003] In the field of extractor hoods, it is known that, in addition to cleaning the air of grease and other contaminants, they also remove odors. This additional air purification is of particular interest for extractor hoods that are operated in such a way that the air is returned to the room in which the extractor hood is operated after cleaning, or that are operated in such a way that the air is recirculated to another room in the building, for example, via a domestic ventilation system. Such extractor hoods are also called recirculation hoods.

[0004] So-called recirculation filters are known for these hoods; they act as odor filters, for example in the form of activated carbon filters or the like. The recirculation filter can be integrated into the appliance, i.e. the extractor hood, and positioned, for example, between a grease filter, which can be an expanded metal filter, and the extractor hood fan in the intake air stream. A disadvantage of this recirculation filtering is a high volume flow loss, which occurs because the intake air stream must be guided over the recirculation filter. It is also known to install the recirculation filter downstream of the extractor hood. In this case, the recirculation filter can be arranged, for example, in the chimney or another panel of the extractor hood downstream of the fan. This can reduce the volume flow loss.However, the recirculation filter must be positioned above the fan and therefore usually in a position that is difficult for the user to access, making replacing the recirculation filter difficult or impossible. In particular, the user may have to remove the panel, such as the chimney, to access the recirculation filter. The same applies to recirculation units that are positioned separately from the extractor hood, for example on an upper cabinet in a kitchen unit, and in which the recirculation filter is integrated. In this case, the user must access the area above the upper cabinet to replace the recirculation filter and may also have to remove panel elements of the recirculation unit to replace the recirculation filter. A recirculation filter can have activated carbon as a filter element housed in a housing. This filter element has the ability to absorb chemicals, gases and unpleasant odors.Other filter elements are activated carbon filter mats, which are available in various sizes and thicknesses. These can be used as filter elements in the housings of air purifiers, extractor hoods or in ventilation systems.

[0005] Such a recirculating air extractor hood is known, for example, from DE 83 03 454 U1. This discloses a wall- or ceiling-mounted recirculating air extractor hood for use above a cooking area or a corresponding dust or fume source, comprising an intake fan, a filter assembly, a hood housing with air ducts, and a device for generating an air curtain directed downward from the hood, which completely or at least partially prevents the fumes drawn in by the fan from the fume source from flowing out or escaping.

[0006] From DE 10 2011 084 912 A1, an extractor hood with a recirculation filter is known, which is detachably held in a mounting frame for simplified replacement and the mounting frame is movably attached to the housing of the recirculation unit via a linear guide.

[0007] To maintain air purification quality, the recirculating air filters of conventional extractor hoods must be changed at intervals specified by the manufacturer. Changing these recirculating air filters requires replacing them completely. This means that the used recirculating air filter, including the housing and filter element, is disposed of as waste. During disposal, the various materials, such as plastic and metal, from which the housings are typically made must be separated from the filter element itself, which can be activated carbon granules or an activated carbon mat. Disclosure of the invention

[0008] The object of the invention is to at least partially improve the extractor hood filters or recirculation filters known from the prior art. In particular, the object of the present invention is to provide a new recirculation filter that can be reused over the course of replacement intervals, thus eliminating the need to dispose of the entire filter and replace it or exchange it with a new one.

[0009] The above object is achieved by a recirculating air filter for an extractor hood with at least one housing with a closure element and with at least one filter element accommodated in the housing with the features of claim 1 and by a system with the recirculating air filter according to the invention and a replacement filter element with the features of claim 9.

[0010] Further advantages, features and details which may be essential to the invention emerge from the subclaims, the description and the drawings.

[0011] The recirculating air filter according to the invention for an extractor hood with at least one housing with a closure element and with at least one filter element accommodated in the housing includes the technical teaching that the housing can be opened in a resealable manner via the closure element in order to replace the filter element with a replacement filter element.

[0012] In contrast to known recirculating air filters, which must be replaced as a whole several times during the replacement intervals after a certain period of operation in an extractor hood and must be disposed of as waste that must be separated, the recirculating air filter according to the invention is designed with a housing that accommodates the filter element and can be reclosed by a closure element, for example a cover element or a housing lid, so that the used filter element can be removed from the housing in the open position. After removing the old or used filter element, it can be replaced with a new filter element, hereinafter also referred to as a replacement filter element, by inserting it into the housing.Once the new filter element, i.e. the replacement or exchange filter element, has been inserted or filled into the housing, the housing can be closed again using the locking element and the recirculation filter can be reinserted into the extractor hood. During the filter element replacement interval, no additional waste is generated other than the used filter element, which is a bonus for the environment. Furthermore, the filter element, in the form of activated carbon or coconut, for example, can be composted and used as plant fertilizer. This not only means that no residual waste to be disposed of is generated by the recirculation air filter according to the invention, but the composted filter element, which can be used as fertilizer, is even biologically recyclable. Accordingly, the present invention fulfills current demands for a clean environment by avoiding residual waste.

[0013] For the purposes of the present invention, "extractor hood" refers to, among other things, extractor hoods, downdraft extractors, or tabletop extractors used to clean the air of grease and other contaminants and to remove odors from the air in private and commercial kitchens. For the sake of clarity, the term "extractor hood" is used synonymously for these extractor hoods.

[0014] The closure element is preferably designed in the form of a cover. The cover can be detachably connected to the housing via fastening elements such as screws. To detach the cover element from the housing, the fastening elements must therefore first be loosened; in the case of screws, these must at least be unscrewed from the housing in order to be able to remove the closure element from the housing.

[0015] If the closure element in the form of the cover itself has an openable and resealable opening through which the used filter element can be removed or poured out of the housing in order to insert or pour a replacement filter element into the housing through the opening, the closure element does not have to be separated from the housing to replace the filter element. In this case, the closure element can either be an integral part of the housing, i.e. the housing with the closure element is designed as a one-piece monolithic component, or the closure element is materially bonded to the housing, for example by means of an adhesive connection, or is connected to the housing via a permanent connection such as a rivet connection.

[0016] Another advantageous embodiment of an openable and resealable connection between the closure element and the housing of the recirculating air filter according to the invention is a mechanical connection that can be established and removed. Such a connection can be a threaded connection between the closure element and the housing. For example, in the case of a cylindrical recirculating air filter, a thread with a profiled notch can advantageously be continuously spirally formed on the underside of the closure element to form an external thread that runs in the wall of the cylindrically designed cavity of the housing, forming an internal thread.A further advantageous embodiment of an openable and resealable connection between the closure element and the housing when the recirculating air filter is designed as a column filter can be in the form of a bayonet lock, wherein the closure element is inserted into the housing, or vice versa, and the closure element is rotated relative to the housing to establish a detachable mechanical connection between the closure element and the housing. To open the connection, the closure element is rotated relative to the housing in the opposite direction to separate the nested parts from one another.

[0017] Since the filter element can be designed in the form of granules or bulk material, or in the form of a filter mat, or as a combination of the materials mentioned, this is independent of the shape of the recirculating air filter, particularly in the form of granules or bulk material. Therefore, any shape is conceivable for the recirculating air filter according to the invention, such as a column shape or an angular or box shape, as used as recirculating air filters in downdraft extractors or table fans. Furthermore, the recirculating air filter according to the invention can be advantageously adapted to different extractor hood motors. The usual connections for these motors have a diameter of 120 mm and 150 mm. By means of an adapter, which is part of the system mentioned here, the recirculating air filter according to the invention is designed for connection to these motors.

[0018] A further aspect of the present invention is a system comprising the recirculating air filter according to the invention and at least one replacement filter element. The advantage of such a system is that the replacement filter element can be offered as a replacement element suitable for the recirculating air filter according to the invention. This means that with a filter element in the form of bulk material, for example activated carbon granules or coconut granules, the replacement filter element can be offered in the appropriate bulk quantity. If the filter element is designed as a mat or textile, for example in the form of activated carbon mats, these can be offered as a replacement filter element that can be inserted into the housing of the recirculating air filter according to the invention without additional adaptation steps such as cutting or shaping.

[0019] Advantageously, the system additionally comprises an adapter by means of which the above-described adaptation of the recirculating air filter according to the invention is permitted.

[0020] In order to avoid repetitions regarding the advantages of the rear wall according to the invention, reference is made to the description of the advantageous embodiments of the milking parlor according to the invention and the disclosure by this description is fully incorporated and vice versa. Preferred embodiments:

[0021] Further measures improving the invention are presented in more detail below with the description of preferred embodiments of the invention with reference to the figures. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. It should be noted that the embodiments illustrated in the figures are merely descriptive and are not intended to limit the invention in any way.

[0022] They show: Fig. 1 in a perspective view, a recirculation filter designed as a column filter with a closure element and a cylindrical housing and an adapter for adaptation to extractor motors; Fig. 2 the column filter from figure in a plan view from above of the housing and the filter element accommodated in the housing; Fig. 3 shows a perspective view of an embodiment of a recirculating air filter designed as a column filter with a mechanical connection designed as a bayonet lock between the closure element and the housing; Fig. 4A and Fig. 4B show a top view of the closure element of a recirculating air filter designed as a column filter, wherein an opening is formed in the closure element for removing and filling a filter element designed as a bulk material; and Fig. 5A-5D filter element variants or replacement filter element variants.

[0023] In the different figures, identical parts are always provided with the same reference symbols, which is why they are usually only described once.

[0024] Fig. 1 shows a perspective view of a recirculating air filter 1 designed as a column filter 1.1. The recirculating air filter 1 has a cylindrical housing 2 into which a filter element 4 is inserted or filled. The housing wall 2.1 of the housing 2 is made of a double-walled “mesh”. The housing 2 can be closed and opened again by means of a closure element 3, in this case in the form of a cover 3.1 or lid. In the illustration shown, the housing 2 with the closure element 3 is in an open position. In this open position, the filter element 4, which is to be changed according to the change interval, can be removed from the housing 2 and a replacement filter element 4.1 can be inserted into the housing 2 or the housing 2 can be refilled with the filter element 4.1.1 is placed in the housing 2, the closure element 3 can be placed back on the housing 2 and, in this case, connected to the housing 2 at least in a force-fitting manner using the fastening element 5 in the form of a screw or via a plurality of fastening elements 5. In the illustration below the housing 2, an adapter 50 is shown which, in this case, is aligned downwards with the reducing part 50.1, which has a diameter of 120 mm, for example, in order to be able to connect the recirculating air filter 1, which has a diameter of 150 mm, for example, to an extractor motor with a connection of 120 mm. To connect the adapter 50 to the housing 2, it can be pushed at least in a form-fitting manner over the lower edge 2.2 of the housing 2, or vice versa.

[0025] Fig. Figure 2 shows the column filter from Figure 1 in a top view of the housing 2. As already described, the housing is designed as a double-walled structure with a first outer wall 2.3 and a second inner wall 2.4, creating a receiving space for a filter element 4 between the two walls 2.3 and 2.4 of the housing 2. The receiving space for the filter element 2 is designed such that it can accommodate bulk material 4.2, such as filter granules, a filter mat 4.3, or a prefabricated filter element 4.4. In this example, a filter mat 4.3 is inserted between the two walls 2.3 and 2.4 of the housing 2, with the two free ends of the filter mat abutting against each other at a joint S:

[0026] Fig. 3 shows a perspective view of an embodiment of a recirculation filter 1, also designed as a column filter 1.1. A bayonet lock 6 is designed between the closure element 3 in the form of a cover 3.1 and the housing 2, which serves to create a mechanical connection that can be established and released between the closure element 3 and the housing 2. In the present case, part 6.2 of the bayonet lock 6 is designed in the housing and is pushed over the corresponding part 6.1 of the bayonet lock 6, which is designed on the closure element 3. Part 6.2 has a longitudinal slot, to the end of which a short transverse slot is connected at a right angle. Part 6.2, on the other hand, has a button that is inserted via the longitudinal slot into the transverse slot in order to mechanically connect the closure element 3 to the housing 2. The mechanical connection is made via a plug-and-twist movement.The two parts to be connected are inserted into one another; approximately perpendicular to the insertion direction, elongated protrusions are applied to both parts at the connection point. However, these protrusions are not continuous, but rather discontinuous (otherwise, mating would not be possible). Since the protrusions are slightly inclined in the plane perpendicular to the insertion direction, a rotational movement of the locking element 3 relative to the housing 2 presses these two parts together. The bayonet lock 6 therefore functions like a thread.

[0027] In Fig. 4A and Fig. 4B shows a top view of the closure element 3 of a recirculating air filter 1 according to the invention, designed as a column filter 1.1. The housing 2 of the column filter 1.1 is filled with a filter element 4 in the form of a bulk material 4.2, such as activated carbon granules or coconut granules. An opening 7 is formed in the closure element 3, which is located in the Fig. 4A is in an open position. In the open position, the filter element 4 can be poured out of the housing 2, for example during a filter element 4 change, which must take place at a change interval specified by the manufacturer of the recirculation filter 1. The turnstile 40, which is designed in the middle of the closure element 3, serves advantageously to handle the rotary movement of the closure element 3 for opening and closing the opening 7, and the position of the turnstile 40 can also be used to indicate the open and closed positions. The arrows below the filter element 4 indicate the direction in which the opening 7 must be turned into the open position and vice versa into the closed position. Fig. Figure 4B shows the opening 7 formed in the closure element 3 in the closed position. The transition of the opening from the open position to the closed position advantageously occurs after the used filter element 4 has been replaced with a replacement filter element 4.1. In this case, the replacement filter element 4.1 is filled in the form of bulk material 4.2 through the opening 7 in the open position into the housing 2 of the recirculating air filter 1.

[0028] Finally, the Fig. 5A to 5D different variants of filter elements 4. In the Fig. 5A shows a filter element 4 designed as a shaped element 4.4, which is adapted to the shape of the housing 2 of a column filter 1.1 and in this form can be easily inserted into the housing 2 as a replacement filter element 4.1. Fig. 5B shows an activated carbon or coconut mat (other sheet-like structures that can be used as filter elements are also conceivable), which, when used in a housing 2 of a column filter 1.1, must be rolled into it (see Fig. 2). If, in contrast, a filter element 4 is to be replaced by a filter element in the form of a bulk material 4.1 during a change interval, outer packaging is recommended, for example in the form of a bag 60, see Fig. 5C or in the form of a cardboard box, which is as in the Fig. 5D is designed as a box 70. Advantageously, the quantity of the filter element 4, namely the quantity of the bulk material 4.2, is stored in the bag 60 or in the box 70, adapted to the volume of the housing 2 of the recirculating air filter 1. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 83 03 454 U1

[0005] DE 10 2011 084 912 A1

[0006]

Claims

[1] Recirculating air filter (1) for an extractor hood with at least one housing (2) with a closure element (3) and with at least one filter element (4) accommodated in the housing (2), characterized by that the housing (2) can be opened and reclosed via the closure element (3) in order to replace the filter element (4) with a replacement filter element (4.1). [2] Recirculating air filter (1) according to claim 1, characterized by that the closure element (3) is designed in the form of a cover (3.1) which is detachably connected to the housing (2) via fastening elements (5). [3] Recirculating air filter (1) according to claim 1 or claim 2, characterized by that a connection (6) in the form of a mechanical connection (6.1,6.2) that can be established and released is provided between the closure element (3) and the housing (2). [4] Recirculating air filter (1) according to one of the preceding claims, characterized bythat an openable and resealable opening (7) is formed in the closure element (3) in the form of the cover (3.2), wherein, in order to replace the filter element (4), the filter element (4) can be removed from the housing (2) via the opening (7) and a replacement filter element (4.1) can be filled or inserted into the housing (2) via the opening (7). [5] Recirculating air filter (1) according to one of the preceding claims, characterized by that the housing (2) is designed for use in extractor hoods. [6] Recirculating air filter (1) according to claim 5, characterized by that the housing can be adapted to extractor motors with different diameters and different connections. [7] Recirculating air filter (1) according to one of claims 1 to 4, characterized by that the housing (2) is designed for use in downdraft extractors. [8] Recirculating air filter (1) according to one of claims 1 to 4, characterized bythat the housing (2) is designed for use in table hoods. [9] System (100) comprising the recirculating air filter (1) according to one of the preceding claims and at least one replacement filter element (4.1). [10] System (100) according to claim 9, characterized by that the replacement filter element (4.1) is designed in the form of a bulk material (4.2) for filling into the housing (2) of the recirculating air filter (1). [11] System (100) according to claim 9, characterized by that the replacement filter element (4.1) is designed in the form of a filter mat (4.3) for insertion or placement into the housing (2) of the recirculating air filter (1). [12] System (100) according to claim 9, characterized by that the replacement filter element (4.1) is designed in the form of a shaped element (4.4) for insertion or insertion into the housing (2) of the recirculating air filter (1). [13] System (100) according to one of the preceding claims, supplemented by an adapter (50), wherein the adapter (50) is designed to adapt the installation situation of the housing (2) of the recirculating air filter (1) to extractor motors with different diameters and / or different connections.

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