Cooking device

Abstract

Cooking device (1) comprising a cooking surface (2), a cooking surface housing (3) arranged thereon, one or more cooking zones (4) formed on the surface of the cooking surface (2), a recess (6) extending through the cooking surface housing (3) and the cooking surface (2), and a fan device configured to extract cooking vapors through the recess (6), and at least one fan wheel (7) arranged beneath the cooking surface (2), and at least one drive motor (8) with stator elements (8a) and rotor elements (8b), wherein the stator elements (8a) are designed as electromagnets, and the rotor elements (8b) are designed as permanent magnets and are arranged on the fan wheel (7), characterized in that the fan device is arranged on the recess (6), wherein the stator elements (8a) are arranged circumferentially around the recess (6) within the cooking surface housing (3), and the rotor elements (8b) are arranged on the outer circumference of the fan wheel (7). are arranged.。

Description

[0001] The invention relates to a cooking device comprising a cooking hob, a cooking hob housing arranged thereon, one or more cooking zones which are formed on the surface of the cooking hob, a recess which leads through the cooking hob housing and the cooking hob, and a fan device arranged to extract cooking fumes through the recess, and at least one fan wheel which is arranged below the cooking hob and at least one drive motor with stator elements and rotor elements, wherein the stator elements are designed as electromagnets, and the rotor elements are designed as permanent magnets and are arranged on the fan wheel.

[0002] Such a cooking appliance is known from WO 2019 / 068421 A1. A disadvantage of this cooking appliance is the large height required to arrange the grease filter and fan unit one above the other.

[0003] EP 3 055 923 B1 mentions that axial flux motors can be used in ventilation systems.

[0004] EP 3 670 925 A1, in turn, discloses a cooking appliance. There, the fan device is arranged entirely beneath the cooktop. The drive motor is located outside the fan device to prevent it from being affected by the extracted vapors. Locating the drive motor outside the fan device in an additional housing that at least partially encloses the drive motor requires additional installation space. Furthermore, the drive motor must be supplied with power, necessitating additional wiring.

[0005] The object of the invention is to further develop known cooking appliances so that they are overall smaller, particularly flatter, and the fan device is particularly easy to maintain and install. A flat design is desirable to ensure that as much usable storage space as possible remains below a kitchen countertop in which the cooking appliance is installed.

[0006] For this purpose, the invention proposes, starting from a cooking device of the type mentioned at the outset, that the fan device is arranged on the recess, wherein the stator elements are arranged circumferentially around the recess within the hob housing and the rotor elements are arranged directly on the outer circumference of the fan wheel, particularly preferably on the upper end face of the fan wheel.

[0007] By arranging the electromagnets in the cooktop housing, they are protected from the extracted vapors and can also be supplied with electrical power directly via the cooktop's electronics. Overall, the cooking appliance according to the invention is also very flat, and the power transmission to the fan wheel via the rotor elements, which are designed as permanent magnets and arranged directly on the fan wheel, is almost optimal. All current-carrying elements of the cooking appliance are protected by the cooktop housing. The magnetic forces are transmitted from the stator to the rotor elements through the cooktop housing. To avoid eddy current losses, this is preferably made of plastic or another electrically non-conductive material.

[0008] An advantageous embodiment of the invention provides that the fan device is designed as a radial fan, wherein the axis of rotation of the fan wheel arranged below the recess is aligned vertically. In this design, the radial fan sucks the vapors downwards through the recess in the axial direction and then discharges them laterally through the outer surface of the fan wheel. The diameter of the fan wheel is ideally adapted to the diameter of the recess. The air above the hob is thus sucked away particularly well and the fan device is nevertheless very flat. The air is only deflected once from the axial suction direction (from top to bottom) into the radial discharge direction of the radial fan. Flow losses are thus minimized. The fan wheel is ideally surrounded by a fan housing (e.g. in the form of a spiral housing) through which the sucked-in air is e.g.into an exhaust duct connected to the fan housing. The air is then recirculated through the exhaust duct, fed to an odor filter, or blown outside.

[0009] A preferred development of the invention provides that a grease filter is inserted into the recess and / or into the volume defined by the fan wheel, i.e. into the inner volume of the radial fan. For this purpose, the grease filter is adapted to the shape and diameter of the recess, has a casing and a base, and is open at the top. For maintenance and cleaning, the grease filter can be easily removed from the recess. The entire fan device is thus protected from grease and other viscous and solid substances. The grease filter can be designed, for example, as an expanded metal filter. The use of the inner free volume of the radial fan, i.e. the volume within the fan wheel, for the grease filter is particularly advantageous because it allows the installation space required for the fan device to be minimized. No separate volume needs to be provided for the grease filter.This makes the fan device particularly small and flat. This is ultimately achieved through the inventive design of the drive motor. Because the stator and rotor elements are located within the cooktop housing and on the fan wheel, respectively, the interior volume of the fan wheel remains free of drive motor components and can be used for the grease filter insert.

[0010] A particularly preferred development of the invention provides that a fan housing is arranged around the fan wheel, which has a collecting device that is closed at the bottom and connecting means for attachment to the cooktop housing that can be released without tools. The collecting device forms the base of the fan housing, so that the fan wheel is enclosed on the sides and underside. Water and other liquid substances that penetrate through the recess are collected in the collecting device. For easy maintenance and cleaning, the collecting device has connecting means that enable the collecting device to be connected to and released from the cooktop housing without tools. Corresponding connecting means can be arranged on the cooktop housing, so that, for example, a secure but also easily removable snap or click connection is possible.Once the collecting device has been removed for cleaning, the fan wheel can also be serviced or replaced.

[0011] Furthermore, it is advantageous if the collecting device has a base with a groove around its perimeter. The liquid substances collect in the groove. This prevents contact with the fan impeller and makes cleaning the collecting device easier.

[0012] Another preferred embodiment provides for the drive motor to be designed as an axial flux motor. In contrast to the commonly used radial flux motors, a higher torque density and a higher power density can be achieved. Furthermore, less material in the form of copper and iron is required.

[0013] A useful development of the invention provides for the recess to be partially covered by an air inlet grille. The air inlet grille prevents larger objects from entering the fan device through the recess. The user also cannot accidentally reach into the recess and come into contact with the fan device. The air inlet grille has virtually no impact on air extraction.

[0014] It is particularly advantageous if the fan wheel has a surface area of ​​40,000 to 60,000 mm 2and a fan impeller height of more than 49 mm. This ensures that the speed of the fan device lies in a range of 1600 to 2600 rpm, ideally less than 2000 rpm. At speeds in this range, the fan device is correspondingly quiet. Nevertheless, the overall height of the cooking appliance, i.e., the dimension from the top of the cooking surface to the bottom of the drip tray, can be limited to less than 250 mm, preferably less than 200 mm, and particularly preferably less than 150 mm.

[0015] An embodiment of the invention is explained in more detail below with reference to the drawings. They show: Fig. 1: schematically shows a cross section through a cooking device according to the invention in one embodiment; Fig. 2: schematically the cooking device according to the invention from Fig. 1 in exploded view; Fig. 3: schematically a detailed view of the stator and rotor elements of the drive motor from Fig. 2; Fig. 4: schematically a 3D view of the cooking device according to the invention from Fig. 1 from diagonally below.

[0016] In Fig. 1 and Fig. 2, a cooking device according to the invention is designated in its entirety by the reference numeral 1. The cooking device 1 comprises a cooking surface 2, on which a cooking surface housing 3 is arranged. Cooking zones 4 are located on the top side of the cooking surface 2. These can be, for example, induction or ceramic cooking zones. Among other things, a cooking surface electronics unit 5 for controlling the cooking surfaces 4 and, if necessary, other peripheral devices is arranged in the cooking surface housing 3. The cooking surface 2 has a recess 6 in the center, which runs through the cooking surface housing 3 from top to bottom.

[0017] Furthermore, a fan device is provided, which has a fan wheel 7 and a drive motor 8 with stator elements 8a and rotor elements 8b. The fan wheel 7 is arranged horizontally below the recess 6. The stator elements 8a are designed as electromagnets and are arranged circumferentially around the recess 6 within the cooktop housing 3. The rotor elements 8b are designed as permanent magnets and are arranged directly on the fan wheel 7, namely on its upper, front-end outer circumference. The fan wheel 7 is surrounded on the outside by a fan housing 70, which is closed off on its underside by a collecting device 9. The fan wheel 7 is rotatably mounted and supported centrally on the collecting device 9 via a bearing element 13.

[0018] As in Fig. As can be seen in Figure 3, the fan wheel 7 in this exemplary embodiment has a plurality of guide vanes 71 distributed over the outer circumference, which are connected to one another via an upper end ring 72. In this exemplary embodiment, the ring 72 carries the rotor elements 8b on its upper side. On its underside, the fan wheel 7 is closed in a pot-shaped manner.

[0019] An upwardly open, cylindrical grease filter 10 is inserted into the recess 6. It has a circumferential collar 10a at its upper end and projects into the fan wheel 7. The grease filter 10 can be suspended in the recess 6 using the collar 10a. Finally, an air inlet grille 11 is arranged above the recess 6. In other embodiments, the grease filter can also have other shapes; for example, it can be cuboid.

[0020] Overall, the cooking appliance 1 is very flat due to the inventive arrangement of the rotor elements 8b directly on the fan wheel 7 and the stator elements 8a in the cooktop housing 3. The fact that the grease filter 10 extends into the fan wheel 7 also ensures optimal use of the installation space while simultaneously ensuring very good filtration.

[0021] A further advantage of the cooking device 1 according to the invention is that all current-carrying components are arranged in the cooking hob housing 3. As shown in particular in Fig. 2 and Fig. 3, the rotor elements 8b in the form of permanent magnets are arranged directly on the upper edge of the fan wheel 7, evenly distributed around the circumference. The corresponding stator elements 8a in the form of electromagnetic coils are arranged above them in the cooktop housing 3 around the recess 6, evenly distributed. The electromagnetic coils can thus be controlled directly via the cooktop electronics 5. The wall of the cooktop housing 3, which can be comparatively thin, is located in the gap between the stator elements 8a and the rotor elements 8b. The gap has a correspondingly small width, as can be seen in the figures. The drive efficiency is therefore sufficiently high. Additional wiring outside the cooktop housing 3 is not necessary. Furthermore, the electromagnetic coils are protected from environmental influences and, in particular, are not exposed to the cooking vapors extracted by the fan device.This also avoids the risk of a short circuit due to moisture.

[0022] A further advantage of the cooking device 1 according to the invention is that all components that come into contact with fat, moisture, and other substances can be easily removed and cleaned, maintained, or replaced. As shown in Fig. As can be seen in Figure 2, the air inlet grille 11 and the grease filter 10 can simply be removed upwards from the recess 6 in order to clean them or, in particular, to replace the grease filter 10.

[0023] Some of the water condensed from the cooking steam and other substances that are not filtered out by the grease filter 10, such as accidentally spilled food, collect in the collecting device 9. The collecting device 9 has a circumferential groove 9a at its base in which the liquids can collect. The collecting device 9 is assigned to the fan housing 70, which is detachably connected to the cooktop housing 3 by means of clip connecting elements 12 without the need for tools. Accordingly, the fan housing 70, together with the collecting device 9, can be easily detached from the cooktop housing 3 and then emptied and cleaned. The fan wheel 7, which is rotatably mounted on the collecting device 9, can also be removed from the cooking device 1 and then cleaned in the same way.It is also conceivable to provide a closable drain opening (not shown) on the underside of the collecting device, at its lowest point, through which liquids can be easily drained without having to dismantle the collecting device 9 each time.

[0024] Fig. Figure 4 shows a 3D view of the assembled cooking device 1 according to the invention from below. The fan housing 70 is connected to the cooktop housing 3 via the clip connection elements 12. Furthermore, the fan housing 70 has an air outlet 73 through which the sucked-in and filtered air is blown out in the circumferential direction. Additional air guiding elements (not shown here) can be arranged at the air outlet to direct the air flow as required.

[0025] The fan wheel 7 advantageously has the following features: A fan wheel diameter of 160 to 260 mm, whereby the fan wheel height can be adjusted according to the diameter so that the fan wheel surface is in a range of 40,000 to 60,000 mm 2 lies.

[0026] The fan impeller height should not be less than 50 mm. The fan impeller's speed can also be adjusted depending on the fan impeller's surface area. With a larger surface area, the speed can be reduced, thus reducing the fan's noise level. Therefore, the speed is advantageously in the range of 1600 to 2600 rpm, ideally below 2000 rpm. List of reference symbols: 1 cooking device 2 hobs 3 hob housings 4 cooking zones 5 Hob electronics 6 Recess 7 Fan wheel 8 Drive motor 8a Stator elements of the drive motor 8b Rotor elements of the drive motor 9 Catch device 9a Gutter 10 grease filters 10a Collar 11 Air intake grille 12 clip fasteners 13 Bearing element 70 fan housings 71 guide vanes 72 frontal ring 73 Air outlet

Claims

[1] Cooking device (1) comprising a cooking hob (2), a cooking hob housing (3) arranged thereon, one or more cooking zones (4) formed on the surface of the cooking hob (2), a recess (6) leading through the cooking hob housing (3) and the cooking hob (2), and a fan device designed to extract cooking fumes through the recess (6), and at least one fan wheel (7) arranged below the cooking hob (2), and at least one drive motor (8) with stator elements (8a) and rotor elements (8b), wherein the stator elements (8a) are designed as electromagnets, and the rotor elements (8b) are designed as permanent magnets and are arranged on the fan wheel (7), characterized by that the fan device is arranged on the recess (6), wherein the stator elements (8a) are arranged circumferentially around the recess (6) within the hob housing (3) and the rotor elements (8b) are arranged on the outer circumference of the fan wheel (7). [2] Cooking device (1) according to claim 1, characterized by that the fan device is designed as a radial fan, wherein the axis of rotation of the fan wheel (7) arranged below the recess (6) is aligned vertically. [3] Cooking device (1) according to claim 1 or 2, characterized by that a grease filter (10) is inserted into the recess (6) and / or into the volume delimited by the fan wheel (7). [4] Cooking device (1) according to one of the preceding claims, characterized by that a fan housing (70) is arranged circumferentially around the fan wheel (7), which has a downwardly closed collecting device (9) and connecting means for attachment to the hob housing (3) that can be released without tools. [5] Cooking device (1) according to claim 4, characterized by that the collecting device (9) has a bottom surface on the circumference of which a groove (9a) is arranged. [6] Cooking device (1) according to one of the preceding claims, characterized by that the drive motor (8) is designed as an axial flux motor. [7] Cooking device (1) according to one of the preceding claims, characterized by that the recess (6) can be partially covered by means of an air inlet grille (11). [8] Cooking device (1) according to one of claims 2-7, characterized by that the fan wheel (7) has a surface area of ​​40,000 to 60,000 mm 2 and has a fan impeller height of more than 49 mm.

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