Cooking device with camera device

Abstract

The invention relates to a cooking device (1) comprising a housing (4) with a cooking chamber (3) and a first viewing opening (10.1) arranged above the cooking chamber (3) in the housing wall (4.1, 4.2, 4.3, 4.4), a camera device (15) arranged above the first viewing opening (10.1) for observing the cooking chamber (3), a high-frequency generator (13) for heating food (6) placed in the cooking chamber (3) by means of microwave radiation, and a shielding channel (23) extending between the camera device (15) and the first viewing opening (10.1) for shielding the camera device (15) from microwave radiation with an electrically conductive inner wall, wherein the first viewing opening (10.1) is covered by a first viewing window (9.1) and a second viewing window (9.1) is located at the upper end of the shielding channel (23).2) is arranged, wherein an air space (17) is formed between the shielding channel (23) and the camera device (15), and wherein an air supply (18) for supplying cooling air into the air space (17) is arranged on the air space (17).

Description

Technical area

[0001] The invention relates to a cooking appliance comprising a housing with a cooking chamber delimited by a housing wall and a first viewing opening arranged above the cooking chamber in the housing wall, a camera device arranged above the first viewing opening for observing the cooking chamber with an image sensor and a lens defining an optical axis as well as a heating device for heating food placed in the cooking chamber and / or a high-frequency generator for heating food placed in the cooking chamber by means of microwave radiation. Background of the invention

[0002] Cooking appliances, particularly ovens with microwave functionality (so-called combination appliances), are known from the state of the art. Cooking appliances are also known with camera devices, where a camera image allows the user to visually check the cooking status of the food, for example, when the cooking chamber door is closed, or where it is used to identify a specific food and control various functions of the cooking appliance based on this image. For example, predefined cooking programs are started by the cooking appliance depending on the detected food, or, to achieve optimal cooking results, parameters of a cooking program are automatically adjusted to the respective cooking status of the food recorded by image analysis.

[0003] It is fundamentally necessary to protect the camera device from excessively high temperatures to avoid damage. Such damage is a threat to many camera devices or their lenses at temperatures above approximately 120°C. Therefore, it is already known to place the camera device outside the cooking chamber and thermally decouple it from it, for example, from publications EP 3 714 210 B1, EP 3 205 941 B1, WO 2023 / 110746 A1, and US Pat. No. 8,660,297 B2.

[0004] In cooking appliances with microwave functionality, the integration of camera devices also presents the problem that the camera electronics are extremely sensitive to microwave radiation. Depending on the intensity of the radiation, this can lead to interference with image recording and even irreparable damage, particularly to the image sensor. Furthermore, microwave radiation can escape through an opening through which the camera device looks into the cooking chamber. Description of the invention

[0005] Based on the background of the invention, it is an object of the present invention to provide a cooking appliance with a camera device in which the camera device is sufficiently protected against damage.

[0006] The object of the invention is achieved by the features of the independent main claims. Advantageous embodiments are specified in the subclaims. To the extent technically feasible, the teachings of the subclaims can be combined arbitrarily with the teachings of the main and subclaims.

[0007] Advantages of the claimed aspects of the invention are explained below, and preferred modified embodiments of the aspects of the invention are described further below. Explanations, particularly regarding advantages and definitions of features, are essentially descriptive and preferred, but not limiting, examples. If an explanation is limiting, this will be expressly stated.

[0008] To the extent that elements are designated by numbering, for example, "first element," "second element," and "third element," this numbering is intended purely for differentiation in the designation and does not represent any interdependence of the elements or a mandatory sequence of the elements. This means, in particular, that, for example, a device or method does not have to have a "first element" in order to have a "second element." The device or method may also have a "first element" and a "third element" without necessarily having a "second element." Multiple units of an element of a single numbering may also be provided, for example, multiple "first elements."

[0009] According to a first aspect of the invention, the object is achieved by a cooking appliance comprising a housing with a cooking chamber delimited by a housing wall and a first viewing opening in the housing wall arranged above the cooking chamber, a camera device arranged above the first viewing opening for observing the cooking chamber, a heating device for heating food placed in the cooking chamber and / or a high-frequency generator for heating food placed in the cooking chamber by means of microwave radiation, and a shielding channel extending between the camera device and the first viewing opening for shielding the camera device from heat and / or microwave radiation, wherein the first viewing opening is covered by a first viewing window and a second viewing window is arranged at the upper end of the shielding channel,wherein an air space is formed between the shielding channel and the lens, and wherein an air supply for supplying cooling air into the air space is arranged on the air space. the air supply (18) comprises a nozzle (19) and the air supply (18) comprises a nozzle (19) and the lens (15.2) is arranged at least partially in the air space (17). Preferably, the camera device is arranged in the region of the ceiling of the cooking chamber. For a functional setup of the cooking appliance, this means that the terms "top" and "bottom" or "upper" and "lower" are to be understood in relation to the cooking chamber, in particular to the ceiling of the cooking chamber. For example, the upper end of the shielding duct is the end of the shielding duct that is further away from the cooking chamber.

[0010] A cooking appliance is particularly designed as an oven with a microwave function, in which temperatures of approximately 100-250°C are provided in the cooking chamber for preparing food. In particular, the cooking appliance therefore comprises a conventional heating device with top heat, bottom heat, and / or circulating air heating means. The cooking appliance can also be designed, in particular, as an oven with a pyrolysis function and / or a steam cooking function. With a pyrolysis function, temperatures between 400°C and 500°C are reached in the cooking chamber, for example. The cooking appliance can also be designed as a microwave oven. The high-frequency generator particularly comprises a magnetron or a solid-state microwave generator and can, for example, expose the cooking chamber to microwave radiation or couple microwave radiation into the cooking chamber.

[0011] The cooking chamber of the cooking appliance is designed as a cavity in the housing of the cooking appliance that is insulated from an outer wall of the cooking appliance by means of thermal insulation. Preferably, the cooking chamber can be filled with food to be cooked via an opening, or such food can be removed from the cooking chamber via the opening, wherein the opening can be closed, for example, by means of a cooking chamber door. In or on the cooking chamber, means for heating the cooking chamber are provided, for example, means for radiating heat, for convective heat transfer, for heat transfer by conduction and / or for heat transfer by induction, as well as means for circulating the air in the cooking chamber. Heating is understood to mean both increasing and maintaining a cooking chamber temperature with simultaneous heat loss, for example through waste heat.

[0012] The camera device is arranged outside the cooking chamber, with a first viewing opening embedded in a housing wall through which the camera device can observe the cooking chamber. The viewing opening is dimensioned and positioned such that it spans a region of a viewing cone of the camera device and is transparent in this region. The camera device is arranged above the cooking chamber and views from above the area intended for the placement of a cooked item. The camera device comprises, for example, a 2D camera, but can alternatively or additionally also have a 3D camera, for example, designed as a TOF camera.

[0013] The shielding channel extends in particular coaxially to the optical axis and has, for example, at least in sections a rectangular channel cross-section and / or at least in sections a round channel cross-section. In this way, the shielding channel forms, at least in sections, a hollow guide (waveguide) which attenuates microwave radiation with the wavelengths commonly used in cooking appliances, for example, greater than or equal to 12 cm at a frequency of around 2.45 GHz or 32 cm at a frequency of 915 MHz, along its longitudinal extent. Typical microwave frequencies are effectively shielded by this easily implemented structural design of the shielding channel, with only leakage radiation of a negligible magnitude reaching the camera electronics. At the same time, the field of view of the camera device can remain largely unobstructed, which enables the reliable recording of meaningful images of the cooking chamber.

[0014] Preferably, the shielding channel tapers from the cooking chamber toward the camera device, i.e., is funnel-shaped, so that the attenuation of the microwave radiation is further increased due to the tapered channel cross-section. Depending on the selected shape of the (section of) the shielding channel, the precise design of the cross-sectional geometry can be based on a waveguide with a corresponding cross-sectional geometry that is impassable for the relevant wavelength. For example, the shielding channel can have the shape of a pyramid or truncated cone, at least in sections, so that the first camera channel cross-section has a rectangular, circular, or elliptical shape. Other cross-sectional shapes, e.g., polygons, are also conceivable.

[0015] Furthermore, this design makes it possible to create space beyond the duct cross-section, which widens congruently with the tapered duct cross-section. This space, which increases with distance from the cooking chamber, enables advantageous insulation against the heat in the cooking chamber.

[0016] Furthermore, the shielding channel defines a spatial distance between the first viewing window and the second viewing window.

[0017] The solution to the problem with the cooking appliance described above therefore includes the teaching that, on the one hand, a shielding channel is provided that protects the camera device from damage caused by heat and / or microwave radiation that would reach the electronics of the camera device. On the other hand, the overall arrangement of the shielding channel, the viewing openings or viewing panels, and the air space, which is actively cooled by means of the air supply or enables active cooling of the camera device, enables particularly good thermal decoupling of the camera device from the cooking chamber, so that the camera device is also protected from damage caused by high temperatures. In particular, an insulating space is created between the first viewing panel and the second viewing panel.Overall, a cooking appliance is provided in which the camera device is protected against damage for a variety of functions, in particular including a microwave function and a pyrolysis function. Furthermore, the proposed cooking appliance solves the problem with a simple design, is cost-effective, and is durable.

[0018] In one embodiment of the cooking appliance, the air supply comprises a nozzle, wherein the nozzle is directed in particular towards a lens of the camera device, preferably in such a way that the lens is flowed laterally, i.e. essentially horizontally.

[0019] One aspect is that the air flow is aligned by means of the orientation of the nozzle, wherein the direction of the air flow is defined by a blow-out axis of the nozzle or by a deflection angle of the nozzle and a blow-out axis of the nozzle.

[0020] The blow-out axis forms an angle with a normal plane of the optical axis, which angle is preferably at least 3 degrees and in particular is formed in a range of 5 degrees to 30 degrees.

[0021] Preferably, the air flow is free of fanning. However, it is also possible for the nozzle to be configured and designed so that the air flow is fanned out. The nozzle has a deflection angle that defines the maximum degree of deflection of the air flow from the discharge axis, and thus the degree of fanning out of the air flow.

[0022] The deflection angle is preferably small; in particular, an air flow that is free from fanning has a deflection angle of 0 degrees. It has proven particularly advantageous for the deflection angle to be less than 25 degrees, in particular, the deflection angle is in a range of 5 degrees to 20 degrees.

[0023] A nozzle focuses and accelerates the cooling air flow, allowing components to be cooled specifically and efficiently using forced convection or by creating an air barrier within the air space. By directing the nozzle toward the lens, this particularly damage-prone or temperature-sensitive component is cooled specifically and efficiently. Efficient cooling with the nozzle allows for a relatively low air flow to be set to achieve sufficient cooling, making it easy and cost-effective.

[0024] In a further embodiment, the cooking appliance has a camera housing with a second viewing opening, in particular wherein the camera device is arranged at least partially above the second viewing opening, i.e. further away from the cooking chamber than the second viewing opening. The air space and the air supply are then arranged in the camera housing, for example, while the shielding duct is arranged between the camera housing and the housing wall delimiting the cooking chamber. Particularly advantageously, the camera housing can be pre-assembled outside the cooking appliance and then inserted into the cooking appliance, thus eliminating the need to arrange the individual components in the cramped cooking appliance. In addition, the camera housing can then be easily removed from the cooking appliance for maintenance, repair, or replacement.

[0025] One aspect is that the entire camera device is arranged completely above the second viewing opening. The lens is positioned at a distance from the plane of the lower wall of the camera housing. It is also possible for the distance of the lens to the plane of the lower wall of the camera housing to be zero. However, it is also possible for the camera device to be only partially positioned above the second viewing opening, in particular at least with its center of gravity. This allows the lens to partially penetrate the second viewing opening in the lower wall of the camera housing.

[0026] One aspect is that the second viewing window is arranged at a distance from the second viewing opening, wherein the second viewing window is positioned closer to the first viewing window than the second viewing opening. In particular, the distance of the second viewing opening from the second viewing window is greater than one-tenth of the distance between the second viewing window and the first viewing window. This prevents the air flow intended for cooling the lens from being unnecessarily heated by the second viewing window, since the second viewing window is spaced from the air space carrying the air.

[0027] Preferably, at least the wall of the camera housing in which the second viewing opening is arranged is made of mica. Compared to alternative materials, mica has particularly favorable thermal properties, in particular relatively low thermal conductivity, good thermal stability, and high temperature tolerance without mechanical influence, so that heat transfer between the cooking chamber and the camera device can be further reduced. To minimize heat transfer through the lower wall of the camera housing, it is preferably constructed from a suitable material. Mica is just one solution. The lower wall could also be made of plastic or silicone, although plastic is preferred.

[0028] One aspect is that the lower wall of the camera housing, i.e. the wall in the area of ​​the second viewing window or the wall closest to the second viewing window, is equipped with targeted openings to the space below. The space below the lower wall of the camera housing is delimited in the direction of the cooking chamber by the shielding duct and / or the second viewing window. Through the openings, a slight overpressure can arise in the air-filled space above the lower wall of the camera housing compared to the area of ​​the device insulation or the space below the lower wall of the camera housing. Likewise, the slight overpressure in the air-filled space above the lower wall of the camera housing can also arise compared to the air-filled space in the shielding duct. A slight overpressure is understood to be an additional pressure of less than one bar. The slight overpressure prevents vapors from the cooking chamber from possibly escaping.leaks or from the area of ​​the device insulation and can penetrate and condense.

[0029] Particularly preferably, a first seal, in particular a glass fiber seal, is arranged between the shielding channel and the camera housing. In this way, the interior of the shielding channel or the second viewing window is sealed from an adjacent exterior space of the cooking chamber and, in particular, protected from contamination by fibers of a thermal insulation arranged there. A glass fiber seal also prevents a thermal bridge between the shielding channel and the camera housing.

[0030] In a further embodiment of the cooking appliance, the shielding duct and the housing form a plurality of contact points around the circumference of the shielding duct, wherein the shielding duct and the housing are contact-free between the contact points. In this way, a stable connection is created between the shielding duct and the housing or the housing wall, so that the shielding duct is fixed in its position and cannot slip even during assembly / disassembly of the camera housing or the camera device. At the same time, the contact area between the shielding duct and the housing or housing wall is reduced to a necessary minimum in order to reduce heat conduction between the two components as much as possible. The contact points are designed, for example, as weld points, screw connections and / or pin connections, in particular rivet connections.The distance between the contact points is chosen in particular such that microwave radiation of the relevant frequencies and wavelengths cannot pass through the gaps formed between the contact points.

[0031] Preferably, a second seal is arranged in the region of the contact points and / or between the shielding channel and the housing. This second seal is arranged, for example, between the contact points, around the contact points, outside or inside the contact points, in particular around the shielding channel. In this way, the interior of the shielding channel or the viewing panels are sealed from an adjacent exterior space of the cooking chamber and, in particular, are protected from contamination by fibers of a thermal insulation arranged there. Furthermore, the selection of an appropriate insulating sealant prevents a thermal bridge between the shielding channel and the housing or housing wall.

[0032] One aspect is that the second seal is arranged between the first viewing window and the second viewing window. Preferably, the second seal is spaced from the first viewing window at a distance greater than one-tenth, in particular greater than one-third, of the distance between the first viewing window and the second viewing window.

[0033] The various features described above, and their combination, result in low heat transfer between the housing and the camera device, allowing a correspondingly short distance between the camera device and the housing without risking damage to the camera device. Advantageously, the viewing openings can then be selected relatively small if the camera device has a large viewing cone.

[0034] In a particularly preferred embodiment of the cooking appliance, the second viewing window has an electrically conductive transparent layer, wherein the electrically conductive transparent layer is in galvanic contact with the shielding channel. This further reduces the leakage of microwave radiation reaching the camera device. Furthermore, the transparent layer reflects infrared radiation emanating from the cooking chamber, thus reducing the heat input to the camera device from this infrared radiation.

[0035] The electrically conductive transparent layer is preferably formed as an indium tin oxide coating, a fluorine-doped tin oxide coating, or a metal grid. These materials offer good transparency, so that the view of the camera device is not significantly obstructed. At the same time, these materials offer good electrical conductivity and thus advantageously shield the camera device against leakage radiation.

[0036] The metal grid can be designed as a coating on the second viewing pane. It is also possible for the metal grid to be embedded in the second viewing pane. Preferably, the metal grid is not a component of the second viewing pane but a separate part which is arranged in the shielding channel at a distance from the second viewing pane. Regardless of the specific embodiment, the metal grid is galvanically connected to the shielding channel, in particular fastened to the preferably metallic shielding channel by a welded connection. Furthermore, an opaque, electrically conductive layer is preferably formed in an edge region of the second viewing pane. This layer then lies outside the field of view of the camera device and therefore does not need to have transparent properties.The layer can then be designed more simply and cost-effectively than the transparent layer and provide the contact between the transparent layer and the shielding channel. For example, the opaque layer is formed by a metallically conductive foil or a metallically conductive lacquer, particularly applied by screen printing.

[0037] One aspect is that the opaque, electrically conductive edge coating is applied to the thin transparent coating. The edge coating serves primarily to protect or reinforce the transparent coating in the edge area. This is intended to prevent, for example, damage to the thin transparent layer due to movement of the third seal.

[0038] Another aspect is that the conductive lacquer is designed as a paste containing silver particles. After printing, this paste is sintered under heat, for example, in a furnace, so that it forms a solid conductive bond with the coating of the disc.

[0039] Furthermore, an electrically conductive third seal is preferably arranged between the second viewing window and the shielding channel, wherein the third seal forms the galvanic contact between the electrically conductive transparent layer and the shielding channel. For this purpose, the third seal can be in contact with the opaque layer and / or the transparent layer. For example, the third seal is formed from a metallic mesh or from a silicone containing metal particles. Seals made from metallic mesh are formed from knitted, very thin wire that is pressed into a mold. A silicone containing metal particles has the advantage that, in addition to establishing the galvanic contact, the third seal also serves as a barrier against environmental influences and against the penetration of fibers from a thermal insulation arranged outside the cooking chamber.

[0040] In a particularly preferred embodiment, the camera device has an image sensor and a lens defining an optical axis, wherein the shielding channel has a first channel cross-section with a cross-sectional geometry impassable for microwave radiation with a wavelength greater than or equal to 12 cm at a microwave frequency of around 2.45 GHz or for microwave radiation with a wavelength greater than or equal to 32 cm at a microwave frequency of around 915 MHz at a distance measured parallel to the optical axis from an end of the lens facing the cooking chamber. These wavelengths or microwave frequencies represent the wavelengths mostly used in cooking appliances, against which effective shielding is thus created. In a preferred embodiment of the invention, the distance from the first camera channel cross-section to the end of the lens facing the cooking chamber is 20 mm to 50 mm, preferably 25 mm to 40 mm.Surprisingly, it has been found that with these distances, a compact structure with effective shielding of the microwave radiation can be achieved.

[0041] As already partially described above, the shielding channel is funnel-shaped, at least in sections. In this way, effective attenuation of the microwave radiation can be achieved using simple structural means. Funnels with a rounded cross-section, e.g., elliptical, oval, or circular cross-section (truncated cone-shaped funnel), as well as with angular cross-sections, such as rectangular cross-sections (truncated pyramid-shaped funnel), or polygonal cross-sections are possible.

[0042] It has proven advantageous for all non-transparent components in the camera's optical path to be designed or coated with a low-reflection or matte black finish. This prevents artifacts in the image that could otherwise be caused by reflections from, for example, the cooking chamber lighting. This design or coating is provided in particular for the shielding channel and / or the funnel-shaped section of the first housing wall and / or the mount and / or the lower wall of the camera housing and / or a grid in the shielding channel.

[0043] In a preferred embodiment, the cooking appliance has a cooling air device for providing cooling air, wherein the cooling air provided is supplied via the air supply to the air space and also to the high-frequency generator for cooling the latter. Cooling air from a separate air circuit is thus advantageously supplied to both the camera device or the air space and the high-frequency generator, whereby it can be ensured that this cooling air is largely free of impurities and in particular free of fumes from the cooking chamber. In order to sufficiently cool the camera device, relatively low air flows at relatively high temperatures can be sufficient, for example an air flow of at least 5 m / s with a round cross-section of the air supply of 10 mm and at a cooling air temperature of at most 85°C. Alternatively, a cooling air flow of at least 5 m / s can be used for the camera device or the air space.A separate sensor cooling circuit must be provided in the air space, which is only assigned to the camera device and, for example, draws in ambient air of the device or air from cooler regions within the device housing.

[0044] A further seal is preferably provided between the first viewing window and the housing, which is particularly elastic to compensate for dimensional tolerances and thermal expansion. Such an additional seal advantageously reliably prevents vapors from the cooking chamber from penetrating the shielding duct. Short description of the drawings

[0045] The invention will be explained in more detail below with reference to preferred embodiments and the accompanying drawings. The term "figure" is abbreviated to "Fig."

[0046] The drawings show Fig. 1 shows a schematic sectional view through a cooking appliance with a camera device and with a cooking chamber loaded with food to be cooked; Fig. 2a shows a detailed view of a cooking appliance according to one aspect of the invention in a first embodiment; Fig. 2b shows a detailed view of a cooking appliance according to one aspect of the invention in a second embodiment; Fig. 2c shows a detailed view of a cooking appliance according to one aspect of the invention in a third embodiment; and Fig. 3 shows a cross-section through the connecting area between the shielding channel and the housing wall. Detailed description of the drawings

[0047] The described embodiments are merely examples that can be modified and / or supplemented in a variety of ways within the scope of the claims. Each feature described for a specific embodiment can be used independently or in combination with other features in any other embodiment. Each feature described for an embodiment of a specific claim category can also be used correspondingly in an embodiment of a different claim category.

[0048] Figure 1shows a cooking appliance 1 designed as an oven with a partially shown housing 4 and a cooking chamber 3 defined by the shown parts of the housing 4. The cooking chamber 3 is delimited on an upper side by a first housing wall 4.1, on a lower side by a second housing wall 4.2, on a front side by a third housing wall 4.3 and on a rear side by a fourth housing wall 4.4, wherein the cooking chamber 3 is further delimited by housing walls (not shown) on a right side and a left side. A baking tray 5 is arranged in the cooking chamber 3, on which a piece of food 6 to be cooked rests. The housing walls 4.1, 4.2, 4.4 are insulated from an outer shell of the housing 4 (not shown).

[0049] The third housing wall 4.3 is formed by a cooking chamber door 7, which can be swung open to expose or close an opening 8 of the cooking chamber 3. The cooking chamber door 7 is formed from multiple glazing, has a handle 7.1, and is sealed against the first housing wall 4.1 by means of a seal 7.2.

[0050] Above and outside the cooking chamber 3, a camera device 15 is arranged, which is designed to observe the cooking chamber 3 or the cooking product 6 and with regard to its arrangement in Figure 1Initially, only rudimentary details of the invention are shown. Between the camera device 15 and the cooking chamber 3, a first viewing window 9.1 is embedded in a viewing opening 10.1 of the first housing wall 4.1. The camera device 15 is directed downward and observes the cooking chamber 3 through the first viewing window 9.1 in plan view, as indicated by a viewing cone S of the camera device 15 and an optical axis A.

[0051] The cooking appliance 1 has a schematically illustrated heating device 14 and / or a schematically illustrated high-frequency generator 13 for heating food 6 placed in the cooking chamber 3. The heating device 14 can, for example, be designed with top heat, bottom heat, and / or circulating air heating means, which are not illustrated in detail.

[0052] The Figure 2a to 2cshow the arrangement of the camera device 15 above the cooking chamber 3 according to embodiments of the invention in detail. The camera device 15 has an image sensor 15.1 and a lens 15.2, wherein the image sensor 15.1 and the lens 15.2 are held in a holder 16. The holder 16 further forms an air space 17, to which cooling air is supplied via an air supply 18 and a nozzle 19 directed towards the lens 15.2. All of the aforementioned components are arranged in a camera housing 20, of which only a lower wall 20.1 is shown. A second viewing opening 10.2 is arranged in the lower wall 20.1, the circumference of which second viewing opening corresponds to the circumference of the viewing cone S of the camera device 15 at the corresponding height along the optical axis A. Air outlets 26 are formed between the holder 16 and the lower wall 20.1, wherein the cooling air is guided in the air space 17 between the air supply 18 and the air outlet 20.1.Nozzle 19 and the air outlets 26 are indicated by several arrows.

[0053] A shielding channel 23 is arranged between the camera housing 20 and the first housing wall 4.1, and thermal insulation 24 is arranged on both sides of the shielding channel 23. The shielding channel 23 extends between a funnel-shaped section 4.5 of the first housing wall 4.1 and the camera housing 20 and has an electrically conductive inner wall. The funnel-shaped section 4.5 forms the first viewing opening 10.1 and is covered on its underside by the first viewing window 9.1 held by a holder 28. A first seal 25.1 designed as a glass silk seal is arranged between the camera housing 20 and the shielding channel 23. A second seal 25.2 is arranged between the shielding channel 23 and the funnel-shaped section 4.5, with details in this regard Figure 3 can be found.

[0054] At the upper end of the shielding channel 23, a second viewing pane 9.2 is arranged, wherein an insulating, air-filled space 30 is formed between the first viewing pane 9.1 and the second viewing pane 9.2, which is further defined by the funnel-shaped section 4.5 and the shielding channel 23. A conductive transparent layer 29 is arranged on the second viewing pane 9.2. In the embodiment according to Fig. 2a The transparent layer 29 is formed as an indium tin oxide coating and is in contact with a third seal 25.3 formed from a metallic mesh, via which a galvanic contact is formed between the transparent layer 29 and the shielding channel 23. In the embodiment according to Fig. 2bThe transparent layer 29 is formed as an indium tin oxide coating and is in contact with a third seal 25.3 formed from a silicone molding containing metal particles, via which a galvanic contact is formed between the transparent layer 29 and the shielding channel 23. The silicone molding containing metal particles replaces, in comparison with the embodiment according to Fig. 2a also the second seal 25.2 between the shielding channel 23 and the funnel-shaped section 4.5, by extending to the corresponding area. In the embodiment according to Fig. 2c the transparent layer 29 is formed as a metal grid formed directly on the shielding channel 23.

[0055] Fig. 3shows a cross-section through the contact area between the shielding channel 23 and the funnel-shaped section 4.5 of the first housing wall 4.1. The connection between the components is established via four contact points 31, which are designed as welded, screwed, or riveted connections. The second seal 25.2, which separates the components from each other, is arranged outside the contact points 31. List of reference symbols

[0056] 1 Cooking appliance 3 Cooking chamber 4 Housing 4.1 First housing wall 4.2 Second housing wall 4.3 Third housing wall 4.4 Fourth housing wall 4.5 Funnel-shaped section of the first housing wall 5 Baking tray 6 Food to be cooked 7 Cooking chamber door 7.1 Cooking chamber door handle 7.2 Cooking chamber door seal 8 Opening 9.1 First viewing window 9.2 Second viewing window 10.1 First viewing opening 10.2 Second viewing opening 13 High-frequency generator 14 Heating device 15 Camera device 15.1 Image sensor of the camera device 15.2 Lens of the camera device 16 Mount 17 Air space 18 Air supply 19 Nozzle 20 Camera housing 20.1 Lower wall of the camera housing 23 Shielding duct 24 Thermal insulation 25.1First seal 25.2Second seal 25.3Third seal 26Air outlets 28Mounting bracket 29Transparent layer 30Air-filled space 31Contact point AOptical axis SViewing cone

Claims

1. A cooking appliance (1) comprising a housing (4) with a cooking chamber (3) defined by a housing wall (4.1, 4.2, 4.3, 4.4) and a first viewing opening (10.1) arranged above the cooking chamber (3) in the housing wall (4.1, 4.2, 4.3, 4.4); a camera device (15) arranged above the first viewing opening (10.1), with an image sensor (15.1) and a lens (15.2), the lens (15.2) defining an optical axis (A), for observing the cooking chamber (3); a heating device (14) for heating food (6) placed in the cooking chamber (3) and / or a high-frequency generator (13) for heating food (6) placed in the cooking chamber (3) by means of microwave radiation; and a shielding channel (23) extending between the camera device (15) and the first viewing opening (10.1) for shielding the camera device (15) from heat and / or microwave radiation; wherein the first viewing opening (10.1) is formed by a first viewing pane (9.1) is covered and a second viewing window (9.2) is arranged at the upper end of the shielding channel (23); wherein an air space (17) is formed between the shielding channel (23) and the camera device (15); and wherein an air supply (18) for supplying cooling air into the air space (17) is arranged at the air space (17). characterized in that the air supply (18) comprises a nozzle (19) and the lens (15.2) is arranged at least partially in the air space (17).

2. Cooking appliance (1) according to the preceding claim, wherein the nozzle (19) is directed in particular towards the lens (15.2) of the camera device (15).

3. Cooking appliance (1) according to one of the preceding claims, comprising a camera housing (20) with a second viewing opening (10.2), wherein the camera device (15) is arranged in particular above the second viewing opening (10.2).

4. Cooking appliance (1) according to one of the preceding claims, comprising a high-frequency generator (13) for heating food (6) placed in the cooking chamber (3) by means of microwave radiation, wherein the shielding channel (23) has an electrically conductive inner wall for shielding the camera device (15) from heat and / or microwave radiation.

5. Cooking appliance (1) according to the preceding claim, wherein a first seal (25.1), in particular a glass silk seal, is arranged between the shielding channel (23) and the camera housing (20).

6. Cooking appliance (1) according to one of the preceding claims, wherein the shielding channel (23) and the housing (4) form a plurality of contact points (31) with each other around the circumference of the shielding channel (23) and wherein the shielding channel (23) and the housing (4) are contact-free between the contact points (31).

7. Cooking appliance (1) according to the preceding claim, wherein the contact points (31) are designed as welding points, screw connections and / or pin connections.

8. Cooking appliance (1) according to one of the two preceding claims, wherein a second seal (25.2) is arranged in the region of the contact points (31) and / or a second seal (25.2) is arranged between the shielding channel (23) and the housing (4), wherein in particular the second seal (25.2) is arranged around the circumference of the shielding channel (23).

9. Cooking appliance (1) according to one of the preceding claims, wherein the second viewing window (9.2) has an electrically conductive transparent layer (29), wherein the electrically conductive transparent layer (29) is in galvanic contact with the shielding channel (23).

10. Cooking appliance (1) according to the preceding, wherein the electrically conductive transparent layer is designed as an indium tin oxide coating, as a coating of fluorine-doped tin oxide or as a metal grid arranged in the shielding channel (23).

11. Cooking appliance (1) according to one of the two preceding claims, wherein an opaque electrically conductive layer is formed in an edge region of the second viewing window (9.2).

12. Cooking appliance (1) according to one of the three preceding claims, wherein an electrically conductive third seal (25.3) is arranged between the second viewing window (9.2) and the shielding channel (23), and wherein the third seal (25.3) forms the galvanic contact between the electrically conductive transparent layer (29) and the shielding channel (23).

13. Cooking appliance (1) according to the preceding claim, wherein the third seal (25.3) is formed from a metallic mesh or from a silicone containing metal particles.

14. Cooking appliance (1) according to one of the preceding claims, wherein the shielding channel (23) has a first channel cross-section with a cross-sectional geometry that is impassable for microwave radiation with a wavelength greater than or equal to 12 cm at a microwave frequency around 2.45 GHz or for microwave radiation with a wavelength greater than or equal to 32 cm at a microwave frequency around 915 MHz at a distance measured parallel to the optical axis (A) from an end of the lens (15.2) facing the cooking chamber (3).

15. Cooking appliance (1) according to one of the preceding claims, wherein the shielding channel (23) is funnel-shaped at least in sections.

16. Cooking appliance (1) according to one of the preceding claims, comprising a cooling air device for providing cooling air, wherein provided cooling air is supplied via the air supply (18) to the air space (17) and further to the high-frequency generator (13) for cooling thereof.

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