Microwave cooking appliance with illumination opening in cooking chamber wall

Abstract

The invention relates to a microwave oven (2) comprising a cooking chamber wall (1) defining a cooking chamber (3) and having at least one light opening, a receiving frame (6) with a receiving area (6I, 6U) for a window element (8) surrounded by a circumferential first support area (6A), wherein the receiving frame (6) rests on an area of ​​the cooking chamber wall (1) surrounding the light opening (4), a light-transmitting window element (8) inserted into the receiving area (6I, 6U), a microwave-tight, perforated, light-transmitting, and removable cover plate (17) covering the window element (8) with a circumferential second support area (17A), wherein the second support area (17A) rests on the first support area (6A) via a circumferential band-shaped microwave seal (9; 26), and an outer edge and / or an inner edge of the microwave seal (9; 26) as a toothed row. (12, 13) is formed and has several teeth (25;29, 31) at least one row of teeth is bent upwards in the direction of the second support area (17A). The invention is particularly advantageously applicable to stand-alone microwave ovens and ovens with microwave function.;

Description

[0001] The invention relates to a microwave oven comprising a cooking chamber wall that defines a cooking chamber and has at least one illumination opening. The invention is particularly advantageously applicable to standalone microwave ovens and ovens with a microwave function.

[0002] DE 1 591 387 A discloses a seal for high-frequency waves in high-frequency, in particular microwave, devices by means of spring contact strips or rings which are attached on one side by clamping to a component movable against another fixed component in the direction of their greatest extension, wherein the spring contact strips or rings are pre-bent over the area of ​​their mounting or clamping surface to increase the contact area within this clamping surface and improve the contact.

[0003] DE 10 2009 040 669 A1 discloses a closure element for the loading opening of the heating chamber of a microwave oven, wherein this loading opening is projected at its circumference by a plate element of the closure element. In order to enable this plate element to form a microwave-tight seal in the area surrounding the loading opening, it is proposed to provide the plate element with a plurality of spring tabs at its circumference. In particularly preferred embodiments, these spring tabs are manufactured integrally with the plate element and pre-bent towards the loading opening.

[0004] US 1,765,443 B discloses a combination of a conductive shielding plate with an opening and a removable conductive shielding plate for covering this opening, and elastic conductive means arranged between the plates at the edge of the opening to ensure good electrical contact between the plates. The elastic conductive means may have an elastic conductive flange that is transversely slotted to form a plurality of independently compliant flange sections attached to one of the plates in the correct position to be located between the plates and adjacent to the edge of the opening when the plates are brought together, thus ensuring good electrical contact between them.

[0005] US 5,043,528 B discloses a spring-finger EMI seal in which portions of the finger parts are shaped such that they can be completely flattened with negligible permanent deformation. When used in a weld, they can therefore be flattened to provide a wide metal-to-metal contact for low electrical impedance across the weld, while simultaneously acting as a positive mechanical stop. In a preferred embodiment, when the weld separates, the tips of the finger parts press firmly against one of the weld surfaces to prevent snagging, a common cause of spring-finger damage.

[0006] US 5,959,244 B discloses an EMI seal formed from a conductive foil with a hole in it. A first set of conductive fingers is arranged along the circumference of the hole and projects from the conductive foil on the front side. A second set of conductive fingers is arranged along the circumference of the hole and projects from the conductive foil on the back side. The first conductive fingers are nested alternately with the second conductive fingers. Each of the first conductive fingers comprises a first and a second section defined by a border. The first section is arranged in the plane of the foil. The second section is arranged in a plane orthogonal to the plane of the foil. The first conductive fingers are used to detect a conductive section of a plate. The second conductive fingers are used to detect a conductive section of a component.The conductive foil and the first and second sets of conductive fingers are made of spring steel. A third set of conductive fingers, similar to the first two, may be included and arranged around the outer perimeter of the conductive foil. In an electronic component assembly with EMI reduction properties, an EMI gasket is positioned between the component and the conductive outer plate. An intermediate plate may be inserted between the gasket and the outer plate. Holes in the intermediate plate allow the first conductive fingers to make contact with the outer plate.

[0007] It is the Task The present invention aims to overcome at least some of the disadvantages of the prior art and, in particular, to provide a particularly large microwave-tight window that can be replaced in a cooking chamber wall of a microwave oven in a simple and inexpensive manner.

[0008] This problem is solved according to the features of the independent claims. Preferred embodiments can be found in particular in the dependent claims.

[0009] The task is solved by a microwave cooking appliance, having a cooking chamber wall defining the cooking chamber, which has at least one opening ("lighting opening"), a frame ("receiving frame") with a receiving area for a window element, which is surrounded by a circumferential ("first") support area, wherein the receiving frame rests on an area of ​​the cooking chamber wall surrounding the lighting opening, a translucent window element inserted into the receiving area, a microwave-proof perforated, translucent and removable cover plate covering the window element with a circumferential ("second") support area, where the second support area rests on the first support area via a circumferential band-shaped microwave seal, an outer edge and / or an inner edge of the microwave seal is formed as a row of teeth and several teeth of at least one row of teeth are bent upwards in the direction of the second support area.

[0010] The assembly comprising the mounting frame, the window element, the microwave seal, and the cover plate will hereinafter be referred to, without limitation of generality, as the "window" or "lighting window." The window serves to allow light generated by a lighting device located outside the cooking chamber to pass into the cooking chamber, while simultaneously preventing both microwave radiation and the atmosphere of the cooking chamber, which may be hot and contain fats, aerosols, etc., from escaping through the lighting opening into areas outside the cooking chamber.

[0011] This window offers the advantage of providing a translucent window in the oven wall with excellent microwave sealing, even at high microwave power, compared to openings with metal mesh. This, in turn, allows for the installation of particularly large windows. The window is also highly temperature-resistant, for example, compared to silicone seals reinforced with metal fibers between the two contact surfaces. Furthermore, the window is inexpensive to manufacture and lightweight. In addition, unlike welding the mounting frame and cover plate, the window element can be easily and non-destructively replaced.

[0012] A microwave oven is primarily a household appliance. It can be a dedicated microwave oven or a combination microwave oven, such as a microwave oven with an additional resistance heating element, a conventional oven with a microwave function, etc. The microwaves can be generated, for example, by a magnetron or a semiconductor microwave generator. They can operate at frequencies in the range of 2.455 GHz or around 915 MHz. The cooking chamber is designed to hold food to be cooked with microwaves. The typically metallic walls of the cooking chamber contain the food, except for a loading opening, usually at the front, through which the food is added. This loading opening can be sealed with a microwave-tight door.

[0013] The mounting frame rests on the oven wall, specifically on its outer side facing away from the oven. The mounting frame is in electrical contact with the oven wall. The mounting frame is firmly attached to the oven wall, for example, by welding. The surrounding mounting frame has an open central section or opening.

[0014] One design feature is that the mounting frame is laterally stepped from the outside to the inside, with an inner edge protruding from an outer edge towards the oven wall. The receiving area for the window element can then be formed, in particular, by the inner edge and its lateral surroundings, into which the window element can be inserted.

[0015] One embodiment involves only the inner edge resting on the oven wall, while the outer edge is spaced away from it. This advantageously reduces the thermal influence of the oven on the outer edge. A further development involves the inner edge partially extending into the lighting opening.

[0016] The receiving area is specifically designed to securely hold the window element. This allows the window element to be easily inserted into and removed from the receiving area (i.e., without any additional fastening such as gluing, etc.). The receiving area provides a stop for the window element in the insertion direction and a lateral form-fit, enabling precise positioning of the window element within the receiving frame. Removal and insertion are performed from the side facing away from the cooking chamber, which can also be described as the receiving area being open on the side facing away from the cooking chamber.

[0017] The window element can be transparent or opaque, for example. It can be made of plastic, glass, or glass-ceramic. However, the window element itself is typically not microwave-proof. The window element can also be referred to as a window pane.

[0018] It is a further development that an edge area of ​​the window element is provided with a circumferential seal. This advantageously serves to reliably prevent the escape of the atmosphere from the cooking chamber. The seal can be made of silicone, for example, especially silicone enriched with metal fibers.

[0019] The cover plate covers the mounting frame and the window element on the side facing away from the cooking chamber. The cover plate presses the window element, or rather its seal, against the mounting frame, so that the window element is held in place by a clamping fit. The cover plate can therefore also be referred to as a pressure plate.

[0020] Because the cover plate is detachably attached, it can be removed without damage, for example by a user or a service technician. This, in turn, offers the advantage that the window element can be easily removed from the mounting frame after the cover plate has been removed, for example for cleaning or replacement. The detachable attachment of the cover plate can be achieved, for example, by screws, clamps, snap-in fasteners, etc.

[0021] The cover plate has, in particular, an inner ("perforated") area comprising a multitude or array of holes shaped and sized to allow light to pass through but not microwave radiation. The number and size of the holes are sufficient to allow enough light to illuminate the cooking chamber. The perforated area covers the window, in particular its entirety, and extends laterally to the outer edge of the inner rim of the mounting frame. The perforated area is surrounded by an outer rim that forms the secondary, circumferential support area.

[0022] The fact that the second contact area rests on the first contact area via the microwave seal implies that the microwave seal is positioned between the two contact areas, and in particular, is compressed between them when installed. The microwave seal serves to establish the most continuous possible electrical contact between the cover plate and the cover frame, thus preventing microwaves from passing between the cover plate and the cover frame. This effect of the microwave seal is advantageously enhanced by the presence of at least one raised row of teeth.

[0023] Furthermore, it has been found that this effect can be significantly improved if at least several teeth, and in particular all teeth of at least one of the two rows of teeth, are bent upwards towards the second contact area or towards the cover plate. Generally speaking, it is advantageous for the teeth of the microwave seal to be bent upwards in different directions; that is, if at least one, and in particular several, of the teeth are bent upwards towards the second contact area, and at least one, and in particular several, other teeth are bent upwards in the opposite direction. This also applies if these teeth are located in the same row.It is therefore already significantly advantageous if the microwave seal has only one row of teeth whose teeth are bent in different directions, and also if the microwave seal has an inner and an outer row of teeth whose teeth within one or both rows are bent in different directions. It is particularly advantageous if the teeth bent in different directions are arranged in a regular pattern.

[0024] This design features a microwave seal with an outer row of teeth on its outer edge and an inner row of teeth on its inner edge. This achieves a particularly high sealing effect. The rows of teeth are also positioned between the two contact areas of the mounting frame and the cover plate.

[0025] A tooth row, as teeth, comprises several small marginal sections spaced apart along the edge, separated circumferentially from adjacent marginal sections (including other teeth) by a gap. The sealing effect is particularly effective if the teeth of the tooth row(s) are arranged completely around the outer edge, possibly with only short interruptions, especially for other functional areas such as holes, tabs, etc. The teeth of a tooth row can all have the same shape and size. Alternatively, the teeth can have different shapes and / or sizes and can then be arranged in a regular sequence pattern. The shape of the teeth can be, for example, trapezoidal, rectangular, triangular, etc., e.g., with or without rounded corners, etc.

[0026] It is a further development that several, especially all, teeth of the outer and / or inner tooth row are bent upwards or bent out of the plane of the microwave seal. This achieves even better electrical contact between the microwave seal and the two contact areas. In particular, deviations from an ideally parallel position of the two contact areas can be compensated for very effectively. It is a further development that only bent-up edge sections are understood as teeth, or alternatively, unbent edge sections. In the following, without limitation of generality, all short edge sections are considered teeth, i.e., both bent-up and unbent edge sections.

[0027] It is one form of upward bending where the upturned teeth of a row are bent in the same direction. It is a further development where all teeth or marginal sections of a row are upturned. It is a further development where only a portion of the teeth in a row are upturned, particularly in a regular pattern: for example, every second tooth may be upturned, two adjacent teeth may be upturned and the following tooth may not be upturned, and so on. It is a further development where the shape and / or size of upturned teeth differs from the shape and / or size of non-upturned teeth.

[0028] One embodiment involves several teeth of the outer row being bent upwards towards the second bearing area, and several teeth of the inner row being bent upwards in the opposite direction, i.e., towards the first bearing area. This is particularly effective. This embodiment can include all teeth of the outer row being bent upwards towards the second bearing area and / or all teeth of the inner row being bent upwards in the opposite direction, or alternatively, only some teeth of the outer row being bent upwards towards the second bearing area, while the remaining teeth of the outer row are not bent upwards, and / or only some teeth of the inner row being bent upwards in the opposite direction, while the remaining teeth of the inner row are not bent upwards.However, it is also possible for several teeth in the inner row to be bent upwards towards the second bearing surface, and several teeth in the outer row to be bent upwards in the opposite direction. In principle, the teeth in a row can also be bent upwards in opposite directions.

[0029] One embodiment involves the lighting aperture having a rectangular shape, particularly with rounded corners. This is advantageously very easy to implement. However, the shape of the lighting aperture is not limited and can be, for example, round, oval, n-sided with n = 3 or n > 4, etc., or have no rounded corners, etc.

[0030] One design feature is a rectangular light opening with sides measuring at least 15 mm x 60 mm. This allows for a particularly large area for light transmission while maintaining very effective microwave sealing, thus ensuring excellent illumination of the cooking chamber.

[0031] It is a design such that the microwave seal has at least one of the following dimensions: Length of an inner recess at least 60 mm; width of the inner recess at least 15 mm; width of the microwave seal perpendicular to the circumferential direction, corresponding to the tip-to-tip distance of opposing teeth of the inner and outer tooth row between 7 mm and 10 mm; curvature of the teeth between 10° and 15°; tip-to-tip distance of adjacent teeth between 1.2 mm and 3 mm; base-to-base distance of adjacent teeth between 0.4 and 2 mm; height of the teeth perpendicular to the circumferential direction between 1.5 and 3 mm, in particular between 1.5 and 2 mm, in particular 1.7 mm; angle of the tooth flanks between 15° and 35°, in particular 25° to 35°, in particular 30°.

[0032] These dimensions have proven to be particularly advantageous for effective microwave sealing, especially in combination.

[0033] This design features several studs protruding from the first support area, facing away from the cooking chamber or into the outer surface of the appliance. At least the microwave seal and the second support area of ​​the cover plate have recesses that correspond to these studs, and nuts are screwed onto the studs. These nuts press the second support area of ​​the cover plate, via the microwave seal, onto the first support area of ​​the mounting frame and hold it in place. This advantageously allows for precise and reliable assembly of these components in a simple manner. Specifically, the studs enable a high, yet precisely adjustable, contact pressure. Furthermore, removing the nuts and pulling the cover plate off the studs provides access to the window element, which can then be easily removed, for example, for cleaning or replacement.The arrangement with the stud screws also allows for easy re-fitting and microwave-proof fastening of the cover plate.

[0034] It is a further development that the studs are arranged at approximately equal intervals around the circumference of the first bearing area. This advantageously enables a particularly uniform contact pressure in the circumferential direction, which prevents local bending and thus undesirable gap formation even more effectively. It is a further development that at least six, and preferably at least eight, studs are present, resulting in a highly uniform contact pressure with even simpler assembly. It is a further development that no more than eight studs are present to avoid making assembly too complex. Specifically, one stud can be present in the transverse direction and three studs in the longitudinal direction.

[0035] It is a design in which at least one tab extends from the oven wall in the direction away from the oven, the mounting frame, the microwave seal, and the cover plate have recesses corresponding to the at least one tab, and the at least one tab is inserted through the corresponding recesses and may, in particular, be bent over. This simplifies the installation of the microwave seal and the cover plate, for example, by first placing them onto the tab(s) and thus positioning them so that they can then be easily attached to the studs.

[0036] One design feature is that the window element is clamped between the mounting frame and the cover plate. This makes assembly particularly easy.

[0037] It is a configuration in which at least one lighting device with at least one light source is arranged on the side of the cooking chamber wall facing away from the cooking chamber (i.e., in the area of ​​the appliance outside the cooking chamber). This lighting device is designed (i.e., configured and arranged) to generate light and shine it into the cooking chamber through the perforated area of ​​the cover plate and the window element. The at least one light source can, for example, comprise one or more LEDs. The lighting device can, for example, comprise one or more light guides, one or more mirrors, etc.

[0038] One embodiment of the lighting device comprises a printed circuit board with at least one light source arranged on one side of the board. The side of the board with the light source is oriented towards the cover plate, and the other side of the board is connected to a heat sink. The fact that the side of the board with the light source is oriented towards the cover plate includes, in particular, that the board is arranged parallel to and spaced behind the cover plate.

[0039] It is a further development that the heat sink can be attached to at least one of the studs and screwed in place. This allows for particularly easy installation, precise alignment of the lighting device, and, if necessary, also easy grounding.

[0040] The properties, features and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more easily understood in connection with the following schematic description of an exemplary embodiment, which will be explained in more detail in conjunction with the drawings. Fig. 1 shows an exploded view in oblique perspective of a section of the cooking chamber wall of a microwave oven in the area of ​​a light opening, looking at the outer surface of the cooking chamber wall facing away from the cooking chamber; Fig. 2 shows another oblique view of a section of the cooking chamber wall in the area of ​​the light opening, looking at the outer surface of the cooking chamber wall facing away from the cooking chamber; Fig. 3 shows yet another oblique view of a section of the cooking chamber wall in the area of ​​the light opening, looking at the outer surface of the cooking chamber wall facing away from the cooking chamber, with the window and light fixture fully installed; Fig. 4 shows a sectional view in top view of yet another section of the cooking chamber wall in the area of ​​the light opening, with the window and light fixture; Fig.5. As a sectional view from an oblique angle above, the inner side of the cooking chamber wall facing the cooking chamber shows another section of the cooking chamber wall with window and lighting device; Fig. 6 shows a variant of a microwave seal in an oblique view; and Fig. 7 shows a section of the microwave seal in a top view. Fig. 6 .

[0041] Fig. 1 Figure 1 shows an exploded view in oblique perspective of a section of, for example, a side wall of the cooking chamber 1 of a household microwave oven 2. The household microwave oven 2 can be, for example, a standalone microwave oven or an oven with a microwave function.

[0042] The cooking chamber wall 1 encloses a cooking chamber 3 in which food can be treated by exposure to microwaves. The cooking chamber wall 1 is electrically conductive, in particular metallic. It can, for example, be formed from a single or multiple pieces of sheet metal. On one front side of the household microwave oven 2, the cooking chamber wall 1 has a loading opening that can be closed microwave-tight by means of a door (not shown).

[0043] In the section shown, looking at an outer surface 1A of the cooking chamber wall 1 facing away from the cooking chamber, a lighting opening 4 is provided in the cooking chamber wall 1. The lighting opening 4 has a longer side of at least 60 mm and a shorter side in the horizontal transverse direction of at least 15 mm.

[0044] The lighting opening 4. The lighting opening 4 is surrounded by a border area 4B, which forms a boundary or edge 4R with a rectangular base shape and rounded edges for the lighting opening 4.

[0045] A circumferential, band-shaped frame ("receiving frame") 6 is mounted on the edge region 4B. It has an inner edge region 6I, which rests on the edge region 4B of the lighting opening 4 and is fastened there, e.g., welded. The inner edge region 6I is laterally surrounded by an outer edge region 6A, which projects in a stepped manner relative to the inner edge region 6I, i.e., is spaced from the cooking chamber wall 1 and is connected to the inner edge region 6I via a side flange 6U. The receiving frame 6 is made of an electrically conductive material and can be a sheet metal part. Several, here eight, stud bolts 5 project perpendicularly from the outer edge region 6A, distributed around its circumference and directed against the direction of the cooking chamber 3.

[0046] A window element 8 can be inserted into the receiving area formed by the inner edge region 6I and the side border 6U. The window element 8 can be transparent or opaque. It can be made of, for example, glass, glass-ceramic, or plastic. A circumferential edge 8R of the window element 8 is shaped such that a window seal 33 (see Fig. 4 ) can be mounted on it, which can be precisely positioned and reliably adhered to it.

[0047] A frame-like, band-shaped microwave seal 9 is placed on the surface of the outer edge region 6A facing away from the cooking chamber, surrounding an inner recess 10. It has a rectangular base shape with beveled corners. The microwave seal 9 is made of an electrically conductive material and can be a sheet metal part. The outer edge region 6A of the mounting frame 6 thus serves as the "first" contact area.

[0048] The microwave seal 9 has cutouts 11 for the studs 5. The microwave seal 9 has an outer row of teeth 12 on its outer edge and an inner row of teeth 13 on its inner edge. At its upper and lower edges, it each has a lateral projection 15 equipped with a slot 14. Tabs 16, attached to the oven wall 1 and projecting vertically in the opposite direction to the oven cavity 3, can be inserted through the slots 14. This provides the advantage of particularly easy installation of the microwave seal 9 if the tabs 16 project further than the studs 5, allowing the microwave seal 9 to be placed onto the tabs 16 before being slid over the studs 5.

[0049] A plate ("cover plate") 17 made of electrically conductive material is placed on the microwave seal 9. The microwave seal 9 can, for example, be a sheet metal part. The cover plate 17 has a circumferential outer rim 17A that surrounds a perforated inner area 17I. The outer rim 17A, or rather its contact area with the microwave seal 9, corresponds to the "second" support area. Holes for the stud screws 5 are provided in the outer rim 17A. The holes 19 of the inner area 17I are shaped, dimensioned, and spaced such that microwaves of the wavelength band used (e.g., 2.45 GHz or approximately 915 MHz) cannot pass through them, while light can. The cover plate 17 is thus microwave-tight but translucent. At least on its upper edge section, the cover plate 17 has a lateral projection 21 equipped with a slot 20.The slots 20 allow the tabs 16 to be inserted, which offers the advantage of particularly easy mounting of the cover plate 17.

[0050] When the oven chamber wall 1, mounting frame 6, microwave seal 9, and cover plate 17 are assembled, the studs 5 protrude from the recesses, in particular holes, into an appliance compartment 23 located outside the oven chamber 3, so that nuts 22 can be screwed onto them. Tightening the nuts 22 presses the outer edge 17A of the cover plate 17 onto the microwave seal 9, and the latter onto the outer edge 6A of the mounting frame 6. The window element 8 can be held in place by clamping between the inner edge 6I of the mounting frame 6 and, if applicable, on the inner edge 4B on the one hand, and the cover plate 17 on the other.

[0051] In equipment room 23 there is a lighting device 24 (see Figs. 3 to 5), which has one or more light sources 34, e.g. LEDs. The light emitted by the light sources 34 passes at least mostly through the perforated inner area 17I, the window element 8, and the lighting opening 4 into the cooking chamber 3 and can, for example, illuminate the food there.

[0052] The assembly comprising the mounting frame 6 with the stud screws 5, the window element 8, the microwave seal 9, the cover plate 17 and the nuts 22 can also be referred to as the "window" or "lighting window".

[0053] Fig. 2 The oblique view shows a further section of the cooking chamber wall 1 in the area of ​​the lighting opening 4 in the assembled state without window element 8, cover plate 17 and nuts 22.

[0054] The outer tooth row 12 and the inner tooth row 13 of the microwave seal 9 are continuous and interrupted only by the cutouts 11 and the projections 15. Both tooth rows 12, 13 have identically shaped teeth 25 with equal, in particular equidistant, spacing between adjacent teeth 25. The teeth 25 are formed here particularly simply by straight cuts starting at the edge, with the two cuts for each tooth 25 being inclined to the edge and to each other. Specifically, the teeth 25 of the outer tooth row 12 are bent upwards from the plane of the microwave seal 9 towards the outer edge region 17A of the cover plate 17, while the teeth 25 of the inner tooth row 13 are bent upwards in the opposite direction, i.e., towards the outer edge region 6A of the mounting frame 6. It is a further development that the teeth 25 are bent upwards at an angle of between 10° and 15°.However, the microwave seal 9 can also be installed in the reversed direction while maintaining an effective sealing effect, with the teeth 25 of the outer tooth row 12 then being bent towards the outer edge region 6A, while the teeth 25 of the inner tooth row 13 are bent towards the outer edge region 17A.

[0055] In particular, the microwave seal 9 can have the following properties: Length of the inner recess 10 at least 60 mm; width of the inner recess 10 at least 15 mm; width of the straight sections of the microwave seal 9 between 7 mm and 10 mm; tip-to-tip distance of adjacent teeth 25 along the straight sections between 1.2 mm and 3 mm; base-to-base distance of adjacent teeth 25 along the straight sections between 0.4 and 2 mm; angle between the tooth flanks of the teeth 25 between 25° and 35°.

[0056] Fig. 3Figure 1 shows a further oblique view of the oven wall 1 in the area of ​​the lighting opening 4, looking towards the outer surface 1A facing away from the oven with the window 5, 6, 8, 9, 17, 22 fully installed and with the lighting unit 24. A rear heat sink 35 of the lighting unit 24 is shown, which has several cooling fins 36. The light sources 24 are located on the front of the lighting unit 24, which is obscured here. These light sources can be supplied with electrical energy via power supply lines 37, possibly together with a driver. Depending on the installation variant, the heat sink 35 can be attached to the oven wall 1 either via the studs 5 or directly.

[0057] Fig. 4 The sectional view in top view shows a further section of the cooking chamber wall 1 in the area of ​​the lighting opening 4 with windows 5, 6, 8, 9, 17, 22 and lighting device 24. Fig. 5as a sectional view in oblique top view of an inner side 1I of the cooking chamber wall 1 facing the cooking chamber, another section of the cooking chamber wall 1 with window 5, 6, 8, 9, 17, 22 and lighting device 24.

[0058] The lighting device 24 has a circuit board 38, on the back of which the heat sink 35 is mounted and on the front of which several of the light sources 34 are attached. Driver electronics may also be present on the circuit board 38.

[0059] Fig. 6Figure 1 shows an oblique view of a microwave seal 26 according to a further embodiment. The microwave seal 26 can be used as an alternative to the microwave seal 9 in the household microwave oven 2. The microwave seal 26 differs from the microwave seal 9 in that the recesses 11 for the stud screws 5 are exclusively in the form of holes, and in the different design of the outer row of teeth 27 and the inner row of teeth 28. The two rows of teeth 27 and 28 are designed analogously, with their teeth 29 now being formed by means of notches 30 introduced from their respective edges. More precisely, a region between two adjacent notches 30 forms a tooth 29, and an edge region 31 remaining between two teeth 29 is not bent over. This edge region 31 can itself be considered a tooth, but does not have to be. Along a progression orThe circumferential direction V of the microwave seal 26 then results - outside the recesses 11 and projections 15 - in the following sequence: {notch 30 - tooth 29 - notch 30 - edge area 31}, etc.

[0060] Fig. 7 The figure shows a top view of an enlarged section of the microwave seal 26 in the area of ​​a corner. In a further development, the microwave seal 26 advantageously has the following dimensions: Angle φ between the two notch flanks 25° to 35°, in particular 30°; notch depth T 1.5 to 2 mm, in particular 1.7 mm; tip radius R of a notch 30: 0.2 mm to 0.3 mm, in particular 0.25 mm; root-to-root distance d1 between two notches 30 enclosing an edge region 31: 2.5 to 3 mm, in particular 2.7 mm; tip width b1 of a tooth 29: 0.4 mm to 0.6 mm, in particular 0.5 mm; tip width b2 of an edge region 31 between 1.2 mm and 1.6 mm, in particular 1.4 mm; width b3 of the microwave seal perpendicular to the circumferential direction between 7 mm and 10 mm, in particular 8.5 mm.

[0061] The notch depth T corresponds to the height of the teeth 29 and edge regions 31 perpendicular to the course extension V. While the teeth 29 are bent upwards along the bending lines 32 extending between adjacent notch bases, the edge regions 31 are not bent upwards.

[0062] Of course, the present invention is not limited to the embodiment shown.

[0063] In general, "ein", "eine", etc. can be understood to mean singular or plural, especially in the sense of "at least one" or "one or more", etc., unless this is explicitly excluded, e.g. by the expression "exactly one", etc.

[0064] A numerical specification can also include exactly the specified number as well as a normal tolerance range, unless this is explicitly excluded. Reference symbol list

[0065] 1 Oven wall 1A Outer side of the oven wall 1I Inner side of the oven wall 2 Household microwave oven 3 Oven chamber 4 Light opening 4B Inner edge of the light opening 4R Limit of the light opening 5 Stud bolt 6 Mounting frame 6A Outer edge of the mounting frame 6I Inner edge of the mounting frame 6U Side edge of the mounting frame 7 Hole 8 Window element 8R Edge of the window element 9 Microwave seal 10 Recess 11 Cutout 12 Outer row of teeth 13 Inner row of teeth 14 Slot 15 Projection 16 Tab 17 Cover plate 17A Outer edge of the cover plate 17I Inner area of ​​the cover plate 19 Hole 20 Slot 21 Lateral projection 22 Nut 23 Housing space 24 Light device 25 Tooth 26 Microwave seal 27 Outer row of teeth 28 Inner row of teeth 29 Tooth 30 Notch 31 Edge area 32 Bending line 33 Window seal 34 Light source 35 Heat sink 36 Cooling fin 37 Power supply lines 38 Circuit board b1 Tip width of a tooth b2 Tip width of an edge aread1 Base-to-base distance RS Peak radius T Notch depth V Circumferential direction φ Angle between notch flanks

Claims

1. Microwave oven (2), comprising: - a cooking chamber wall (1) defining a cooking chamber (3) and having at least one light opening; - a mounting frame (6) with a receiving area (6I, 6U) for a window element (8), which is surrounded by a circumferential first support area (6A), wherein the mounting frame (6) rests on an area (4B) of the cooking chamber wall (1) surrounding the light opening (4); - a translucent window element (8) inserted into the receiving area (6I, 6U); - a microwave-tight, perforated, translucent, and removable cover plate (17) covering the window element (8) with a circumferential second support area (17A), wherein - the second support area (17A) rests on the first support area (6A) via a circumferential band-shaped microwave seal (9; 26); - an outer edge and / or an inner edge of the microwave seal (9; 26) is formed as a row of teeth (12, 13) and - several teeth (25;29, 31) at least one row of teeth (12, 13) are bent upwards in the direction of the second bearing area (17A).; 2. Microwave oven (2) according to claim 1, wherein the teeth (25; 29, 31) of the microwave seal (9; 26) are bent in different directions.

3. Microwave oven (2) according to one of the preceding claims, wherein the microwave seal (9; 26) has an outer row of teeth (12) and an inner row of teeth (13) respectively on its outer edge and on its inner edge.

4. Microwave oven (2) according to claim 3, wherein several teeth (25; 29, 31) of the outer row of teeth (12) are bent upwards in the direction of the second support area (17A) and several teeth (25; 29, 31) of the inner row of teeth (13) are bent upwards in the opposite direction, or vice versa.

5. Microwave oven (2) according to one of the preceding claims, wherein all teeth (25; 29, 31) of at least one row of teeth (12, 13) are bent upwards in the same direction.

6. Microwave oven (2) according to one of the preceding claims, wherein the illumination opening (4) has a rectangular shape, in particular with rounded corners, having a length of at least 60 mm and a width of at least 15 mm.

7. Microwave oven (2) according to one of the preceding claims, wherein the microwave seal (9; 26) has at least one of the following dimensions: - length of an inner recess (10) at least 60 mm; - width of the inner recess (10) at least 15 mm; - width (b3) of the microwave seal (9; 26) between 7 mm and 10 mm; - curvature of the teeth (25; 29, 31) between 10° and 15°; - tip-to-tip distance of adjacent teeth (25; 29) between 1.2 mm and 3 mm; - base-to-base distance of adjacent teeth (25; 29) between 0.4 and 2 mm; - angle (φ) of tooth flanks of the teeth (25; 29, 31) between 15° and 35°; 8. Microwave oven (2) according to one of the preceding claims, wherein - several stud bolts (5) protrude from the first support area (6A) against the direction of the cooking chamber (3), - at least the microwave seal (9; 26) and the second support area (17A) of the cover plate (17) have recesses (11, 18) matching the stud bolts (5), and - respective nuts (22) are screwed onto the stud bolts (5), which press the second support area (17A) of the cover plate (17) over the microwave seal (9; 26) onto the first support area (6A) of the support frame (6).

9. Microwave oven (2) according to one of the preceding claims, wherein the receiving frame (6) is stepped laterally from outside to inside, wherein an inner edge region (6I) projects from an outer edge region towards the cooking chamber wall (1) and the outer edge region forms the first support region (6A).

10. Microwave oven (2) according to claim 9, wherein only the inner edge area (6I) rests on the cooking chamber wall (1).

11. Microwave oven (2) according to one of the preceding claims, wherein - at least one tab (16) extends from the oven wall (1) in the direction away from the oven, - at least the microwave seal (9; 26) and the cover plate (17) have recesses (20) matching the at least one tab (16) and - the at least one tab (16) is inserted through the corresponding recesses (20) of the microwave seal (9; 26) and the cover plate (17).

12. Microwave oven (2) according to one of the preceding claims, wherein the window element (8) is a transparent or opaque window element (8), in particular made of plastic or glass, and is clamped between the receiving frame (6) and the cover plate (17).

13. Microwave oven (2) according to claim 12, wherein an edge area (8R) of the window element (8) is provided with a circumferential seal (33).

14. Microwave oven (2) according to one of the preceding claims, wherein at least one lighting device (24) with at least one light source is arranged on the side of the oven wall (1) facing away from the oven chamber, which is provided to generate light and to shine it through the cover plate (17) and the window element (8) into the oven chamber (3).

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