DE29914007U1 - Door for a device, in particular a cooking oven, with unmistakably mountable panes - Google Patents

Description

. &Iacgr; HE-1999/092 *..·*..· .. .. _GS / _Re

09.08.1999

AEG Hausgeräte GmbH D-90429 Nuremberg

Description

Door for an appliance, in particular a cooking oven, with interchangeable panes

The invention relates to a door for an appliance, in particular a cooking oven, preferably for the household.

Doors for domestic ovens are known with a viewing window formed by a translucent outer pane and a translucent inner pane and, if necessary, a translucent intermediate pane arranged in between. A large number of options are known for mounting and fastening these panes in the door.

EP 0 010 829 B1 discloses a viewing window unit for an oven door with several glass panes, each of which is fastened in receiving grooves and arranged parallel to one another. The viewing window unit is installed as a module in the oven door using screws. It is not possible to remove the individual glass panes from the door separately. In some of the embodiments of this known oven door, the glass panes are of different sizes and are held in receiving grooves spaced apart at different distances.

■ ■ DE 26 54 017 A1 discloses a self-contained window unit for installation in an oven door with two glass panes arranged parallel to each other. The front glass pane arranged on the outside of the door can be removed from the door by pressing it against a spring element and then removing it from the door. The other glass pane is permanently mounted. DE 26 54 011 A1 describes embodiments

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in which the two glass panes and the associated holding devices have different dimensions.

From DE 41 18 800 A1 a door for a laboratory cabinet, 5 in particular a heating cabinet, is known with a transparent outer pane, a transparent intermediate pane and a transparent inner pane. The intermediate pane is kept at a distance from the outer pane and the inner pane by sheet metal spacers attached to the door frame. The three panes have identical geometric dimensions and cannot be removed without considerable effort after they have been installed. ' . ■ - .

DE-GM 77 36 544 discloses an oven door with two support profiles that form the two vertical door edges. On the sides facing each other, the two support profiles have several vertical receiving grooves into which two glass panes are inserted, the width and height of which correspond to the dimensions of the door. One of the two glass panes forms the outer pane of the door and is wider than the other glass pane, which forms the inner pane of the door. The inner pane, on the other hand, is higher than the outer pane. End strips that form the upper and lower door edges are attached to the support profiles at the top and bottom by means of screws, which close the hollow spaces of the support profiles at the top and bottom and thereby hold the inserted glass panes in the receiving grooves so that they cannot move. By removing an end strip, the glass panes can be replaced in the event of glass breakage. In the space between the two glass panes, additional grooves are provided into which, if required, additional plates, such as additional radiation protection plates, for example ¹ made of perforated sheet metal or the like, can be inserted.

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The additional mounting grooves in the door known from DE-GM 77 36 are the same distances from each other as the mounting grooves provided for the inner pane. This means that when reinstalling after removing the inner pane and installing another pane of glass, the two panes can be confused. This is particularly disadvantageous in cases where the inner pane has a different heat radiation reflectivity than the intermediate pane. To increase the reflection of the heat radiation emerging from the oven muffle, the inner pane is often provided with a heat radiation reflecting coating, which is significantly less effective if the inner pane is accidentally installed in the intermediate position and a large proportion of the heat radiation has already reached the interior of the door and can escape through the components of the door by heat conduction. ' . ■

DE 191 38 506 Cl discloses a door for a household appliance, in particular for a household fermentation oven, with an outer pane, two support elements attached to the outer pane and an inner pane arranged on the two support elements on the side facing away from the outer pane. The inner pane is removably held in a special holding device. The holding device comprises two

25. elements and a spring element which, when installed, presses the inner pane into the two holding elements and is arranged in a door handle strip attached to the support elements from above. .An intermediate pane can be inserted between the outer pane and the inner pane and the two support elements, which has at least one frame element made of plastic on its edge to maintain a defined distance between the intermediate pane and the outer pane and the inner pane. The intermediate pane can be mounted in the door when the inner pane is removed. The

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The inner pane and the intermediate pane have different geometric dimensions. However, since the intermediate pane is supported on the inner pane, the intermediate pane is not held in the door when the inner pane is removed and can therefore fall out of the door.

The invention is based on the object of specifying a door for an appliance, in particular a household appliance, preferably a cooking oven, into which up to at least three door panes can be mounted unmistakably and in a simple manner and can also be removed again in a simple manner, for example for cleaning purposes.

This object is achieved according to the invention with the features of claim 1. · ·

The door according to claim 1 is intended for an appliance, in particular for a cooking oven, and preferably for a household appliance and comprises a number m of at least three holding devices for holding one door pane each, as well as a number η of at least two and at most m door panes which can be mounted in and removed from a clearly assigned holding device, each of which differs from one another in terms of its geometric dimensions in pairs.

The m holding devices are now designed and arranged in adaptation to the door panes in such a way that each door pane is held in the associated holding device after its assembly, regardless of the presence of another mounted door pane, and the door panes can only be mounted one after the other in the associated holding devices in a predetermined order and can only be dismantled from the associated holding devices in the reverse order.

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This combination of measures creates a door that can be fitted with any number of at least two door panes that can be removed and reinserted from the door in a repeatable and ergonomically favorable manner. The door panes can only be installed in the positions provided and determined by the associated holding device. This ensures that a pane that is to be installed in a certain position, for example with a coating or tint for optical or thermal reasons, is actually installed in the intended position again during production, but especially after the panes have been removed for cleaning or replacement if damaged. In ^cases where the door has more holding devices than door panes, i.e. not all possible positions are fitted with panes, the accidental installation of a removed door pane in one of the positions that should be kept free is also prevented. Because each door pane is individually held in the door, removing one door pane cannot loosen another door pane and accidentally fall out of the door. The risk of damage to the door panes or injury to the person removing the first door pane (assembly person) is thus significantly reduced. The structural determination of the installation and removal sequences for the door panes means that no markings on the door panes are required as memory aids. The person who has removed the door panes for cleaning in the specified order only needs to reinstall the door panes in the reverse order. This is a great mnemonic aid, especially when there are three or more door panes. If, for example, a door pane is accidentally forgotten during reinstallation, the specified installation sequence and the uniqueness, if necessary by successive

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sive removal of the already installed door panes, it is possible to quickly identify which of the free positions the forgotten door pane belongs to. In addition, the assembly person is automatically prompted to remove the panes one by one, thus increasing safety.

Advantageous further developments and embodiments of the door according to the invention emerge from the claims dependent on claim ¹ .
10

In general, the door panes are installed in the door at least approximately parallel to a given installation plane and thus to each other.

The dimensions of the door panes and the associated holding devices can now differ from one another laterally, i.e. parallel to a pane plane in which the panes are preferably extended, and/or vertically, i.e. perpendicular to the pane plane.

The lateral dimensions of the door panes and the laterally measured dimensions of the associated holding devices preferably increase in the order specified for installation.

' ·

The order in which the door panes are installed in the door is preferably from the inside to the outside, so that the innermost door pane must be installed first.

In a preferred embodiment, the door panes are held in the associated holding devices in a force-fitting or at least form-fitting manner.

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In a particularly advantageous embodiment, at least one of the holding devices has a restoring device and an opposing counter surface, whereby the restoring device presses the installed door pane against the counter surface with a restoring force. The restoring device can in particular be formed with one or more elastic elements, i.e. elements that are shaped as a spring element and/or are made of a material with a low modulus of elasticity and therefore exert a restoring force directed against the deforming force when deformed.

The clear assignment of the door panes to the holding devices is particularly advantageous if the door panes are made of different materials and/or have different physical, in particular thermal, properties, in particular different reflectivities for thermal radiation, and for these reasons the order of the door panes in the door is important.

In general, the door panes are at least partially translucent.

In one embodiment, the holding devices for the door panes can have at least one common holding element with m separate support surfaces for placing a door pane on each. The support surfaces of each holding element can in particular be formed in or with at least one receiving groove for holding a door pane. At least one of these receiving grooves is then directed in at least two independent spatial directions, so that the door pane is limited (supported) in two directions perpendicular to it. ■

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In a particularly advantageous embodiment, the door has an additional door pane, which generally forms an outer pane, and at least two support elements, in particular column-like and designed as profile parts, which are attached to this door pane, the support elements carrying at least part of the holding devices for the door panes already mentioned. One of the aforementioned holding elements with several support surfaces is then preferably connected to each of the support elements.

■ or attached to it. .

The outermost of the door panes is now preferably held in the installed state by the associated holding device on the side of the two support elements facing away from the additional pane at a distance from the support elements or resting on them. The other n-1 door panes, on the other hand, are preferably held by the associated holding devices between the support elements at a distance from the support elements or resting on side surfaces of the support elements facing one another.

It is particularly advantageous to design the holding devices in such a way that the door panes can be installed in and/or removed from the holding devices without tools, only by hand.

The door according to the invention is particularly advantageously used for closing the loading opening of an oven muffle of a household oven.
30

To further explain the invention, reference is made to the drawings, each of which schematically shows an embodiment of the door according to the invention. They show:

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FIG 1 shows a part of a door with a holding element for three door panes, which are not installed, in a perspective view,

FIG 2 shows the part of the door according to FIG 1 with a door pane built into the holding element in a perspective view,

FIG 3 shows the part of the door according to FIGS 1 and 2 with two door panes built into the holding element in a perspective view,

FIG 4 shows the part of the door according to FIGS 1 to 3 with three door panes built into the holding element in a perspective view,

FIG 5 is a perspective overall view of a door with a retaining element according to FIG 3 with two installed door panes,

FIG 6 a part of a door with an elastic element for three door panes, which are not installed, in a perspective view,

FIG 7 shows the part of the door according to FIG 6 with a door pane pressed against the elastic element in a perspective view, .

FIG 8 the part of the door according to FIGS 6 and 7 with two door panes pressed against the elastic element in a perspective view,

FIG 9. the part of the door according to FIGS 6 to 8 with three door panes pressed against the elastic element in a longitudinal section,

FIG 10 a door with three door panes each installed in a holding device in a longitudinal section,

FIG 11 shows a part of a door with a holding element for three door panes of different thicknesses.

Corresponding parts are provided with the same reference numerals in FIGS. 1 to 11.

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FIGS. 1 to 4 show a holding element (receiving part) 7 for holding three door panes of a door, wherein the number of door panes increases in FIGS. 1 to 4.

FIG 1 shows the holding element 7 without _a door pane installed. For each of the three door panes - not yet shown in FIG 1 - the holding element 7 has a receiving groove 72, 74 or 79. The receiving groove 72 is formed between a first limiting part 170 and a second limiting part 171 of the holding element 7, the receiving groove 79 between the second limiting part 171 and a third limiting part 172 of the holding element 7 and the third receiving groove 74 between the third limiting part 172 and a fourth limiting part 173 of the holding element 7. A door pane can be inserted into each of the receiving grooves 72, 74 and 79 up to their bottom 174 or 175 or 176 in an insertion direction along the arrow marked ER. The limiting parts 170 to 173 on the one hand and the bases 174 to 176 on the other hand limit the degrees of freedom of movement of an inserted door panel in such a way that it can only be moved essentially parallel to the associated receiving groove 72, 7 4 or 7 9 and is otherwise held essentially free of play. To laterally limit the movement of the door panel in one direction, a lateral limiting part is also provided on the receiving groove 72. Such lateral limiting parts can also be arranged on the other receiving grooves 74 and 7 9, preferably in the same direction (on the same side) as the limiting part 73 on the receiving groove 72. In the illustrated embodiment according to FIG. 1, the receiving grooves 72, 7 4 and 7 9 are designed to accommodate door panels with straight edges that preferably meet at a right angle (rectangular door panels). The receiving grooves can also have a predetermined edge.

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contour of the door panes, which can then be designed to be particularly concave or convex.

According to FIGS. 1 to 4, the holding element 7 has an at least predominantly cuboid-shaped enveloping surface and is open on one of the sides of this cuboid-shaped basic shape. An inner side wall of the holding element 7 is designated 7 6 and an outer side wall, the extension of which forms the limiting part 73, is designated 77. The two side walls 7 6 and 77 are connected via a cover wall 71 running perpendicularly thereto, which merges into the limiting part 170 in the extension. In the exemplary embodiment shown in FIGS. 1 to 4, the holding element 7 is designed as a hollow profile part and is applied to a carrier element 5 with its open side facing away from the cover wall 71. The wall of the carrier element 5 is adapted in shape to the inner wall of the holding element 7, so that an inner side wall 56 of the carrier element 5 lies on the inside of the side wall 76 of the holding element 7, an outer side wall 57 of the carrier element 5 lies on the outer side wall 77 of the holding element 7 and an upper side 51 of the carrier element 5 lies on the inside of the cover wall 71 of the holding element 7. The holding element 7 is locked into corresponding openings 58 in the wall of the carrier element 5 by means of locking projections 7 protruding from the inside of its wall. In FIGS. 1 to 4, only the locking of the outer side wall 77 with the holding element !■ with the outer side wall 57 of the carrier element 5 can be seen. The carrier element 5 is now also designed as a hollow profile part, the walls 51, 56 and 57 of which run in the manner of a column essentially parallel to the insertion direction ER, and for this purpose is preferably formed from a correspondingly, in particular U-shaped, profiled sheet, preferably a steel sheet.

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The side walls 56 and 57 of the carrier element 5 are adjoined by flange-like fastening parts (flange edges) 53 and 50, with which the carrier element 5 is fastened to an outer pane 3 via an adhesive 99. A formation (e.g. embossing) designated 59 in the fastening part 53 serves to maintain a defined distance between the fastening part 53 and the surface of the outer pane 3, so that the adhesive 99 can be applied in a defined thickness. Similar formations 59 are preferably also provided in the opposite fastening part 50. Due to the comparatively large adhesive surface of the adhesive 99, forces from the carrier element 5 are transferred evenly to the outer pane 3, so that shattering of the outer pane 3 due to thermal or mechanical stresses is practically avoided. The adhesive connection 99 also ensures that the carrier element 5 is gently connected to the outer pane 3 during production. However, a screw connection, a snap connection or another connection of the carrier element 5 with the outer pane 3 can also be provided.

The holding element 7 is formed as a molded part from a polymer compound (polymer plastic), preferably a thermoplastic or thermosetting plastic, whereby all components, in particular the limiting parts 73, 170 to 173 and the bottoms 174 to 176 of the receiving grooves 72, 74 and 79, as well as the side walls 76 and 77 and the cover wall 71, are produced in a single manufacturing process, in particular a

'30 injection molding or a drawing process. Without limiting the generality, halogenated or non-halogenated hydrocarbon polymers may be mentioned as materials for the holding element 7, for example polyethylene, polypropylene, polystyrene, polyurethane,

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Polyvinyl chloride and fluorocarbon materials as well as copolymer compounds with these polymers. In applications at higher temperatures, such as in an oven door, temperature-resistant plastics are selected.

The holding element 7 can also be detachably connected to the carrier element 5, for example, by means of a screw connection or permanently connected by means of an adhesive connection. '. . .

In the holding element 7 fastened to the carrier element 5, the two inner receiving grooves 74 and 79 closest to the outer pane 3 only extend to the inner side wall 56 of the carrier element 5 or to a boundary part of the holding element 7 (not shown) in front of it. The outer receiving groove 72, which is furthest away from the outer pane, extends above the carrier element 5 over the entire width of its upper side 51 to the boundary part 73, which directly adjoins the outer side wall 57 of the carrier part 5. The holding element 7 is thus supported by the carrier element 5 practically over its entire inner surface and is thus held stable.

In the embodiment shown in FIG 2, a door pane 4, of which only one corner tapering at a right angle is shown, is now inserted in the insertion direction ER into the innermost receiving groove 74 of the holding element 7. A lower edge 45 of the door pane 4 rests on the bottom of the receiving groove 74. An upper side 41 of the door pane 4 ■ rests on the limiting part 172 and a lower side 42 on the limiting part 173 of the holding element 7. A lateral edge 46 of the door pane 4 running at a right angle to the upper side 41 and lower side 42 as well as to the lower edge 45 can now either be attached to the side wall 56 of the carrier element

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5 or* are kept at a distance from the side wall 56 of the carrier element 5 by a lateral limiting part (spacer) of the receiving groove 74 (not shown). Such an additional lateral limiting part in the receiving groove 74, which is again molded onto the molded part, reduces the heat conduction between the carrier element and the door pane 4 and rattling noises when the door pane 4 otherwise strikes the side wall 56 of the carrier element 5.

According to FIG 3, in addition to the inner door pane 4 already inserted into the receiving groove 74, a second door pane 9 is now inserted into the receiving groove 79 in the insertion direction ER. The door pane 9 rests on the bottom 175 of the receiving groove 79 as a counter surface (support surface) with its lower edge 95 and is supported with the top 91 on the limiting part 171 and the bottom 92 on the limiting part. The lateral edge 96 of the door pane 9 can again rest against the side wall of the carrier element 5, analogous to the door pane 4 according to FIG 2, or be kept at a distance from the side wall 56 of the carrier element 5 by a lateral limiting part of the receiving groove 79 (not shown).

FIG 4 shows an embodiment in which an inner pane 2 is additionally installed in the holding element as a third door pane. The inner pane 2 is inserted into the receiving groove 72 in the insertion direction ER. In the receiving groove 72, the inner pane 2 is held in four of six spatial directions by the limiting part 170, the base 174, the limiting part 171 and the lateral limiting part 73. The lower edge 25 of the inner pane 2 lies on the base 174 of the receiving groove 72, the upper side 21 on the limiting part 170, the

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Bottom side 22 on the limiting part 171 and the side edge 26 on the side limiting part 73.

In the holding element 7, according to FIGS. 1 to 4, three door panes 4, 9 and 2, in particular designed as rectangular flat bodies, are spaced from one another and can be installed essentially parallel to one another.

FIG 5 now shows a door with an outer pane 3 and two built-in door panes 4 and 9. On a flat side of the outer pane 3, in an edge region, a carrier element 5 with a holding element 7 carried thereby as shown in FIGS. 1 to 4 and in an opposite edge region a correspondingly designed carrier element 6 running parallel to the carrier element 5, which carries a holding element 8 designed in accordance with the holding element 7, are fastened. The carrier element 6 and the holding element 8 are arranged and designed at least largely mirror-symmetrically with respect to a plane of symmetry parallel to the carrier elements 5 and 6 and perpendicular to the outer pane 3 to the carrier element 5 and the holding element 7. The holding element

■ 8 has, analogously to the holding element 7, a cover wall 81 on the top side 61 of the carrier element 6 and two side walls 86 and 87 which rest from the outside on the side walls 66 and 67 of the carrier element 6. The inner side wall 86 of the holding element 8 and the inner side wall 76 of the holding element 7 face each other. The holding element 8 also has three receiving grooves 82, 84 and 89 which are designed analogously to the receiving grooves 72, 74 and 79 on the holding element 7.

The holding elements 7 and 8 are each arranged at the lower ends of the associated support elements 5 and 6. At the ends of the support elements 5 and 6 facing away from the holding elements 7 and 8, a perpendicular to the support elements 5

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and 6 is fastened in fastening areas 155 and 165 respectively. Elastic elements 11, 12 and 13 and, if necessary, assembly aids 145 and 15 for the assembly of the door panes are integrated in the support strip 10. Each elastic element 11 to 13 has a support surface (counter surface, pressing surface) for each of the door panes 4 and 9 to be assembled or assembled as well as the inner pane 2 (not shown). For assembly, the two door panes 4 and 9 are first

Ø is pressed in the forward insertion direction designated EV against the corresponding support surfaces of the elastic elements 11 to 13 and centered accordingly, and then subsequently inserted under the effect of the restoring forces exerted by the elastic elements 11 to 13 in the opposite direction ER into the corresponding receiving grooves 7.4 and 84 or 79 and 89 in the holding elements 7 and 8. The inner pane 2, not shown in FIG. 5, can also be mounted in the same way. To remove the door panes 4 and 9, the assembly steps described are reversed, i.e. the door panes 9 and 4 are now pressed one after the other in the reverse order against the restoring force of the elastic elements 11 to 13 and then removed from the receiving grooves 7 9 and 8 9 or 74 and 84. The assembly aids 14 and 15 facilitate the positioning of the door panes 4 and 9 on the elastic elements 11, 12 and 13 and in the holding elements 7 and 8, but generally have no supporting function for the door panes 4 and 9. The structure and function of the elastic elements 11, 12 and 13 as well as the assembly aids 14 and 15 will be described in more detail later with reference to FIGS. 6 to 9.

The installed innermost door pane 4 and the installed second innermost door pane 9 are in the corresponding mounting

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groove 74 or 7 9 of the holding element 7 and the associated receiving groove 84 or 8 9 of the holding element 8 in each case in one of the two lower corner areas and with their upper edge on the support surfaces of the elastic elements 11 to 13 and cantilevered between them. The holding elements 7 and 8 and the elastic elements 11 to 13 together form two holding devices for the two door panes 4 and 9 with a comparatively small contact area to the door panes 4 and 9, so that thermal losses due to heat conduction in the door are kept to a minimum. Both door panes 4 and 9 are held between the side wall 56 of the support element 5 and the side wall 66 of the support element 6 and their movement is laterally limited by these.

The outermost receiving grooves 72 of the holding element 7 and 82 of the holding element 8 as well as the elastic elements 11 to 13 also form a holding device for an inner pane 2 (not shown), as in FIG. 4. To space the inner pane 2 from the support elements 5 and 6, at least one spacer 55 and 65 are arranged on the upper sides 51 and 61 of the support elements 5 and 6, which are elastically designed to mechanically dampen the inner pane and reduce impact noises, and are preferably designed to be sliding at least on their surface facing the inner pane 2, in particular by means of a sliding coating made of polyfluoroethylene, so that the inner pane 2 can be moved along them with little sliding friction. The thicknesses (heights) of the spacers 55 and 65 are now preferably selected to be large enough that the spacers 55 and 65 are not completely elastic when the inner pane 2 is installed. are mechanically demoulded and thereby pre-tension the inner pane 2 in its holding devices in order to reduce noise in the door to a minimum.

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Elastic polymers (elastomers) based on a plastic, a natural rubber or a plastic/natural rubber compound are particularly suitable as elastic materials for the elastic elements 11 to 13 and/or the spacers 55 and 65. A particularly advantageous material is a (solid) silicone (polysiloxane or polyfluorosiloxane), which is also resistant to higher temperatures. However, a polyurethane can also be used, for example, or a plastic known under the trade name Santoprene, or acrylic ester elastomers, ethylene-propylene-diene elastomers or ethylene-vinyl acetate copolymers, or a plastic sold under the trade name Hostaform (if the temperature requirements are not too high). Other advantageous elastomers are halogen-carbon polymers, in particular fluorocarbon elastomers or copolymers with fluorocarbon elastomers, for example a copolymer of tetrafluoroethylene and propylene, or chlorobutadiene elastomers. Elastomers with halogen (in particular fluoro)-carbon compounds are also more temperature-resistant than pure hydrocarbons and have very low coefficients of friction. The elastic modulus (resistance to deformation) of the elastic material can be selected in particular to be below about 5000 N/mm ² , preferably below 2000 N/mm ² .

The door structure according to FIG 5 is characterized by a very simple construction with a small number of parts. Each of the panes 4 and 9 as well as 30, the inner pane 2 (not shown) located in the door interior can be mounted in the door and removed again by hand without the aid of tools. This enables very easy removal of the door panes 4, 9 and 2, in particular

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especially for cleaning purposes or for replacement in case of damage or glass breakage.

In all embodiments, the door is generally intended for closing an opening to the interior of an appliance and in particular for closing a loading opening of a cooking oven, preferably a domestic cooking oven, but is not limited to this application.

All door panels 2, 3, 4 and 9 preferably consist at least predominantly of an optically transparent material, in particular glass or glass ceramic. The transparent door panels 3, 4, 9 and 2 then form a large viewing window in the door in order to be able to look into the interior of the appliance closed off by the door, in particular the interior of the oven muffle.

Particularly in applications where the door must also ensure a certain thermal insulation of the appliance interior it closes off from the outside, the door panels of the door often have different physical and, in particular, thermal properties. If, as in the case of an oven, the interior is at a comparatively high temperature (for example 300° C when cooking and even up to 500° C during a pyrolytic cleaning process), then according to the Stefan-Boltzmann law, a comparatively high proportion of heat is generated at these high temperatures in the form of thermal radiation. In order to keep this thermal radiation in the appliance interior, the door panel closest to the appliance interior, in this case the inner panel 2, and if necessary also the other door panels, in this case the door panel 9 and if necessary also the door panel 4, are preferably coated on their surface with a coating that reflects thermal radiation.

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Furthermore, the inner pane 2 must withstand a higher temperature than the door panes 9 and 4 located further out, so that as a rule different temperature-resistant materials are selected for the inner pane 2, the door pane 9 and the door pane 4.

To achieve the desired optimum thermal insulation effect, it is therefore necessary to always mount the door panes 2, 9 and 4 in the specified positions.

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The inner pane 2 cannot be confused with one of the two door panes 9 and 4 due to its different width compared to the door panes 9 and 4, measured perpendicular to the directions EV and ER, and the correspondingly further outward-going receiving grooves 72 and 82 of the holding elements 7 and 8, so that it can in particular also have the same height, measured parallel to the directions ER and EV, as one of the door panes 9 or 4. For this reason, the two receiving grooves 72 and 79 according to FIGS. 1 to 4 (and correspondingly the receiving grooves 82 and 89 in the holding element 8) of the holding element 7 can also be in one plane, i.e. on the same

height, run.

In order to be able to distinguish the door panes 4 and 9 from one another, the door panes 4 and 9 are of different heights, measured parallel to the directions EV and ER, as shown in FIGS. 1 to .5, and the elastic elements 11, 12 and 13 and the associated receiving grooves 79 and 89 and 74 and 84 of the holding elements 7 and 8 respectively have correspondingly different distances from one another, which are adapted to the dimensions of the door panes 4 and 9. The receiving grooves 74 of the holding element 7 and 84 of the holding element 8 for the door pane 4 are therefore further upwards.

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offset against the insertion direction ER than the receiving grooves 7 9 and 8 9 for the door pane 9. The differences in the heights of the door panes 4 and 9 should not be too great in order to maintain a sufficiently large viewing window and are generally selected between 2 mm and 40 mm, in particular between 5 mm and 20 mm. As a result of these measures, the lateral surfaces of the door panes 4, 9 and 2 increase from the inside to the outside. The innermost door pane 4 is therefore smaller than the door pane 9, while the door pane 9 is in turn smaller than the inner pane 2.

■ If it is also desired to ensure that individual or all of the door panes 2, 4 and 9 always face inwards (or outwards) with the same surface, the corresponding holding devices can be adapted to one another in a further development not shown, for example by asymmetrically designing the receiving grooves 72, 79 and 74 of the holding element 7 in comparison to the holding grooves 82, 89 and 84 in the holding element 8, and the door panes 2, 9 and 4 so that the flat sides of the door panes 2, 4 and 9 can no longer be interchanged.

FIG 6 shows a section of the door according to FIG 5 in its upper right corner area. The door panes 4 and 9 are not installed and therefore not shown. This means that the elastic element 13 can be seen practically in its entirety. The elastic element 13 is formed with a shaped profile part which has a continuous wall 30 and several chambers (hollow spaces, intermediate spaces) 31, which are each separated from one another by a partial area (partition wall) of the wall 30. In the exemplary embodiment shown, the chambers 31 are open on the sides and are only delimited by the wall 30 parallel to the insertion direction EV. The wall 30 of the elastic element 13 comprises individual, under certain

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Angles to each other', in the unloaded state essentially straight and connected to each other, so that the chambers 31 have a generally polyhedral shape. The elastic element 13 is inserted or clamped into an associated receiving pocket 23 which is formed on the carrier strip 10 and can be easily removed from this. In the rear area, as seen in the insertion direction EV, the wall 30' of the elastic element 13 is flat and rests against a rear flat side of the carrier strip 10. On the opposite side, which faces opposite to the direction EV, the wall 30 is stepped and has three flat support surfaces 32, 39 and 34 with the vector EV as the normal vector and diagonally running flanks 33 between the support area 32 and the support area 39 and 35 between the support area 39 and 34 and a further flank 36 adjacent to the support surface 34. The support surface 34 for the door pane 4, the support surface 39 for the door pane 9 and the support surface 32 for the inner pane 2 are now provided. The flanks 36, 35 and 33 are advantageous for stabilizing and as guide aids for the door panes. By designing the elastic element 13 as a hollow profile part with several chambers, the spring effect is considerably increased compared to a solid body made of the same (elastic) material. However, with a correspondingly highly elastic material, a solid body can also be used as elastic element 13.

A further assembly aid is designated 14 and comprises 30. essentially three flat guide elements 141, 142 and 143 arranged parallel to one another and spaced apart from one another. The carrier strip 10 is connected in its edge region to the edge region of the carrier element 5 in a fastening region 155, for example screwed or inserted.

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clips. The carrier element is again glued to the outer pane 3 in the area of the flange edge 53.

According to FIG 7, the door pane 4 is now the first door pane to be pressed in the insertion direction EV onto the associated support surface 34 of the elastic element 13 with a certain force. The force exerted on the elastic element 13 by the door pane 4 leads to a deformation of the areas of the wall 30 lying below the support surface 34, which is indicated by a curvilinear deformation of the webs indicated by dashed lines. The two guide elements 142 and 143 of the assembly aid 14 serve as a means for positioning the door pane 4, but generally do not lie against the door pane 4 when the door pane 4 is inserted. When the door pane 4 has been pressed against the elastic element 13 by a predetermined insertion length in the direction of insertion EV, it can be inserted into the receiving grooves 74 and 84 of the holding elements 7 and 8 on the opposite side as shown in FIG. 5 and is then pressed into these receiving grooves 74 and 84 by the restoring force of the elastic element 13 (and the other elastic elements 11 and 12). The elastic element 13, the door pane 4 and the receiving grooves 74 and 84 are preferably coordinated with one another in such a way that the door pane 4 is held under a certain tension in the fully installed state when it is inserted into the receiving grooves 84 and 85. The elastic element 13 is therefore under a certain pre-tension and is not relieved of force and thus still exerts a restoring force on the door pane 4 even when it is installed. This ensures that the door pane is firmly seated in the receiving grooves 74 and 84. 4 is held firmly between the elastic elements 11 to 13 on the one side and the receiving grooves 74 and 84 on the other side and cannot rattle or even fall out.

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FIG 8 now shows the mounting of the next door pane 9 on the elastic element 13. The door pane 9 is pressed against the associated support surface 39 of the elastic element 13 in the same way as the door pane 4 according to FIG 7 in the insertion direction EV. The guide elements 141 and 142 now serve as guide aids for inserting the door pane 9.

FIG 9 shows a longitudinal section of the elastic element 13 designed as a hollow profile part with three door panes 4, 9 and 2 installed on associated support surfaces 34, 39 and 32. The deformation of the webs of the wall 30 by the door panes 4 and 2 inserted and held under pressure from the unloaded position is indicated in the drawing. Due to this elastic deformation, the elastic element 13 exerts a restoring force against the insertion direction EV, by which the door panes 4, 9 and 2 are pressed downwards.

The different heights of the holding devices for the door panes 2, 4 and 9 can be realized in all embodiments by means of support surfaces arranged in steps relative to one another on the elastic elements 11, 12 and 13 or on the holding elements 7 and 8 in conjunction with support surfaces arranged at the same height or also in steps on the other side, i.e. on the holding elements 7 and 8 or the elastic elements 11, 12 and 13.

The elastic elements 11, 12 and 13 as well as the holding elements 7 and 8 can also be stressed independently of the unique disc installation.

In FIGS. 1 to 9, the holding elements 7 and 8 on the one hand and the elastic elements 11 to 13 on the other hand form

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together three holding devices for the three door panes 4, 9 and 2, whereby each door pane, 2, 9 and 4 is held individually and independently of the other door panes. Due to the special design of the elastic elements 11 to 13 ■ the deformation of the elastic element 13 in the assembly sequence of the door panes 4, 9 and finally 2 increases the restoring force for the individual door panes, so that - even with the significantly thinner design of the elastic element 13 in the area of the support surface 32 - the pre-tension caused by the door panes 4 and 9 produces a sufficient restoring force for the door pane 2. The door panes 4, 9 and 2 must always be installed in the specified order from the inside to the outside and removed from the outside to the inside.

■ FIG 10 now shows another embodiment of a door in which three door panels 100, 200 and 300 can be installed in and removed from an associated holding device. The holding devices for the door panels 100, 200 and 300 are each formed with a receptacle 101 or 201 or 301, in which a spring element 103 or 203 or 303 is arranged, on one side and with a receiving groove 102 or 202 or 302 on the other side. The receptacles 101, 201 and 301 are preferably provided in a common receiving part 150 and separated from one another by intermediate parts 204 and 304 formed on the receiving part 150. The receiving grooves 102, 202 and 302 are formed in a common holding element 160 and are preferably arranged in one plane so that the inserted door panes 100, 200 and 300 are at the same height. The height of the first holding device for the door pane 100 is designated hl and is determined by the distance between the upper limit of the receptacle 101 and the lower limit of the receiving groove 102. Accordingly,

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the heights of the second holding device for the door window

200 with h2 and for the third holding device with h3. The heights hl to h3 of the three holding devices decrease in the order in the direction of installation direction E from the outside to the inside. The distance of the door panel 100 or 300 from the upper limit of the receptacles 101 or.

201 or 301 is designated with dl or d2 or d3. The heights of the door panes 100, 200 and 300 therefore correspond to the differences hl-dl or h2-d2 or h3-d3 and also decrease in the installation direction E from the outside to the inside. An outer pane 400 is arranged on the front side of the receiving part 150 and holding element 160. On the opposite side, support elements 104 for the inner pane 100 are provided on the receiving part 150 in order to provide additional support to the inside. The door panes 100, 200 and 300 are pressed into the receiving grooves 102, 202 or 302 by the associated spring elements 103, 203 or 303 with a predetermined restoring force and are thereby fixed. To remove the door panes 100, 200 or 300, the respective door pane is pulled in the direction designated Fl or F2 or F3 out of the receiving groove 102, 202 or 302 against the spring force of the spring element 103, 203 or 303. To make this possible, the depth t of the receiving grooves 102 to 302 must of course be selected to be smaller than the distances dl to d3 so that the door panes 100 to 300 can actually be removed from the receiving grooves 102 to 302. As soon as the door pane 100, 200 or 300 to be removed is free from the corresponding receiving groove 102, 202 or 302, the door pane can be removed from the door at an angle to the front, opposite to the installation direction E. The dismantling of the door panes 100 to 300 is to be carried out in a predetermined order, namely first the door pane 100, then the door pane and finally the door pane 300. The spring elements 103, 203 and 303 can be formed with steel springs and are attached to the

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The door panes 100, 200 and 300 are secured to the receiving part 150, for example by gluing, screwing or riveting. Due to the different sizes of the door panes 100, 200 and 300 and the associated holding devices, the door panes 100, 200 and 300 can be installed and removed again in an unmistakable manner.

The distinctiveness of the door panes 100, 200 and 300 can additionally or alternatively be achieved by different thicknesses of the door panes 100 to 300 and associated receiving grooves in the holding element 160. Such an embodiment is shown in FIG. 11. The thicknesses of the door panes 100, 200 and 300 are designated by a1 or a2 or a3, the corresponding widths of the receiving grooves 102 or 202 or 302 by bl or b2 or b3.

Claims (19)

1. Door for an appliance, in particular for a cooking oven, preferably for household use, with a) a number m of at least three holding devices ( 74 , 84 , 34 or 79 , 89 , 39 or 72 , 82 , 32 ) for holding one door pane ( 4 , 9 , 2 ), b) a number n of at least two and at most m door panes ( 4 , 9 , 2 ), where a) the n door panes have different geometric dimensions and b) each of the n door panes can be installed in only one of the m holding devices and can be removed again from this, (c) each installed door pane is held in the associated holding device regardless of the presence of another installed door pane and d) the door panes can only be installed into the associated holding devices one after the other in a predetermined order and can only be removed from the associated holding devices one after the other in the reverse order. 2. Door according to claim 1, in which the door panes installed in their associated holding devices are each arranged at least approximately parallel to one another. 3. Door according to claim 2, in which the door panes have laterally different surfaces and the holding devices have correspondingly different lateral dimensions. 4. Door according to claim 3, in which the laterally measured areas of the door panes and the laterally measured dimensions of the retaining devices increase in the order specified for installation. 5. Door according to one of the preceding claims, in which the sequence specified for the installation of the door panes runs from the inside to the outside. 6. Door according to one of the preceding claims, in which the door panes have different thicknesses in pairs and the holding devices have correspondingly different dimensions. 7. Door according to one of the preceding claims, in which each installed door pane is held in the associated holding device substantially without play, in particular under the action of a clamping force. 8. Door according to one of the preceding claims, in which at least one of the holding devices has a restoring device ( 11 , 12 , 13 ) and an opposite counter surface ( 72 , 74 , 79 , 82 , 84 , 89 ) and in which the restoring device presses the installed door pane against the counter surface with a restoring force. 9. Door according to one of the preceding claims, in which the door panes consist of different materials and/or have different physical, in particular thermal, properties, in particular different reflectivities for thermal radiation. 10. Door according to one of the preceding claims, in which the door panes are at least partially optically transparent. 11. Door according to one of the preceding claims with at least one holding element ( 7 , 8 ) with m separate support surfaces for placing a door pane on each of them as a common component of the holding devices for the door panes. 12. Door according to claim 11, wherein each holding element has at least one receiving groove ( 72 , 74 , 79 , 82 , 84 , 89 ) for holding a door pane. 13. Door according to claim 12, wherein at least one receiving groove of each holding element extends in at least two independent spatial directions. 14. Door according to one of the preceding claims with an additional door pane ( 3 ) and at least two support elements ( 5 , 6 ), in particular columnar, connected to this door pane, wherein the support elements carry at least part of the holding devices. 15. Door according to claim 14 when dependent on one of claims 11 to 13, in which a holding element is connected to each of the support elements. 16. Door according to claim 14 or claim 15, wherein the outermost of the n door panes ( 2 ) in the installed state is held at a distance from the support elements or resting on them by the associated holding device on the side of the two support elements facing away from the additional pane, and the further n-1 door panes ( 4 , 9 ) are held at a distance from the support elements or resting on mutually facing side surfaces of the support elements by the associated holding devices between the support elements. 17. Door according to one of the preceding claims, in which the door panes can be installed in and/or removed from the holding devices without tools only by hand. 18. Oven with a) an oven muffle with a loading opening for introducing food to be cooked and b) a door according to one of the preceding claims for closing the loading opening of the furnace muffle.