Component of household appliance comprising micro-indentations, pressing tool and manufacturing method for such component

Abstract

A component (10) of a household appliance, in which a metal plate portion (12) of the component (10) is formed from a metal plate (11); the invention relates to a sheet metal part (12) for a motor vehicle, characterized in that at least one sheet metal surface (12s1, 12s2) of the sheet metal part (12) is provided with regularly arranged micro-dents (14), each micro-dent (14) has a depth (d) perpendicular to the sheet metal surface (12s1, 12s2) which is not less than 40% of the sheet metal thickness (t) of the sheet metal part (12), and each micro-dent preferably has a dimension (l, w) along the sheet metal surface (12s1, 12s2), the dimension is not more than twice the thickness (t) of the metal plate, more preferably not more than twice the thickness (t) of the metal plate.

Description

[0001] The invention relates to a component of a household appliance, such as an oven cavity or a baking tray, wherein a sheet metal part of the component is formed from sheet metal, in particular by a pressing or deep drawing process.

[0002] According to further aspects, the invention also relates to a pressing tool and a production method for such a component.

[0003] In the prior art, these components usually have large and clearly visible protrusions and / or curved structures whose only function is to increase the stiffness of the component as stresses are induced in the material.

[0004] For example, in DE 7516419 U, which discloses a component having the features of the preamble of claim 1, the side walls and the top wall of the interior of a dishwasher produced by expanding annular sheet metal jackets are reinforced by embossed rib-like indentations in the form of a waffle structure.

[0005] Especially for parts that are to be enameled after forming, since the enameling process is carried out at temperatures above 800° C., an increase in rigidity is required, otherwise the part would be deformed and rendered unusable.

[0006] However, there are situations where it is preferred that the surface of a component is as flat and smooth as possible, both for optical reasons and for practical reasons, for example because a smooth and flat surface can be cleaned more easily than a surface with many protrusions or other deformations.

[0007] In light of the above, an object of the present invention is to improve the compromise between stiffness and surface flatness of a component of a household appliance made of sheet metal.

[0008] According to the invention, this object is solved by providing a regular arrangement of micro-dimples on at least one sheet metal surface of the sheet metal portion of the component, wherein each micro-dimple has a depth perpendicular to the sheet metal surface which is not less than 40% of the sheet metal thickness of the sheet metal portion.

[0009] It should be noted that in the present application the term "micro-dents" is understood to relate to small dents, ie dents having a dimension not greater than 1 cm, preferably in the order of a few millimeters, below 5 mm or even below 1 mm along the metal sheet surface.

[0010] The inventors have found that such a regular arrangement of micro-dimples can still significantly improve the stiffness of the resulting component, so that if desired, larger embossed structures provided in the prior art for stiffness reasons can be omitted.

[0011] However, the micro dimples do not necessarily need to completely replace the standard embossed structure. In addition, the embossed structure can also be provided to increase stiffness even further, or the conventional embossed structure can be made smaller or can be provided in a smaller area, thereby avoiding such larger deep drawing radii of the prior art. In addition, the overall thickness of the part can be reduced while maintaining its stiffness, resulting in both energy and cost benefits.

[0012] Preferably, the micro-dimples are all identical or can be classified into several groups, with all micro-dimples of each group being identical and the micro-dimples of different groups differing, for example, in size and / or form.

[0013] According to a specific embodiment, the size of each micro-dent in at least one direction along the surface of the metal plate, preferably in all directions along the surface of the metal plate, is no greater than ten times the thickness of the metal plate, preferably no greater than five times the thickness of the metal plate, more preferably no greater than twice the thickness of the metal plate, and most preferably no greater than one times the thickness of the metal plate.

[0014] Additionally or alternatively, the distance between any two adjacent micro-dimples in the same metal sheet surface may be greater than the dimension of each of these adjacent micro-dimples in at least one direction along the metal sheet surface, preferably in all directions along the metal sheet surface.

[0015] Preferably, the distance between any two adjacent micro-dimples in the same metal sheet surface is two times, more preferably five times, greater than the size of each of the two micro-dimples in at least one direction along the metal sheet surface, preferably in all directions along the metal sheet surface.

[0016] In this way, the overall impression of the component surface remains that of a predominantly flat surface and it further facilitates cleaning.

[0017] It should be noted that the component surface may, but need not be, identical to the sheet metal surface, in particular since the component may comprise further layers covering the sheet metal surface, as will be explained in more detail below.

[0018] For many practical purposes, the thickness of the sheet metal portion of the component may be substantially constant. If this is not the case, the term "sheet metal thickness" should be understood to refer to the average thickness of the sheet metal portion, either over the entire area of ​​the sheet metal portion or limited to an area including the arrangement of micro-dimples.

[0019] According to a preferred embodiment of the invention, the component further comprises at least one enamel layer, which is preferably provided on the metal sheet surface provided with the arrangement of micro-dimples and even more preferably partially or completely fills and hides the micro-dimples, thereby creating a very flat and smooth surface that is both optically pleasing and easy to clean. This is particularly preferred for oven components.

[0020] The sheet metal thickness of the sheet metal portion of the component with or without an enamel layer may be in the range from 0.3 mm to 0.8 mm, preferably from 0.4 mm to 0.7 mm, and even more preferably from 0.5 mm to 0.6 mm.

[0021] The thickness of the enamel layer of a once enameled surface is typically in the range of 80 μm to 200 μm.Some components, such as the oven cavity of a steam oven, may receive two or more enamel layers to increase corrosion resistance.

[0022] The sheet metal used for the component is preferably a cold-rolled steel sheet, in particular a cold-rolled steel sheet for enameling, such as DC04ED, DC03ED, DC04EK or DC06EK according to DIN EN 10209, for example in the September 2013 edition.

[0023] It should be noted that the present invention can support a change from ED materials with direct enameling (e.g. DC04ED) to EK materials with conventional enameling (e.g. DC04EK or DC06EK). Since EK materials offer less shape stability during the firing process, the micro-dimples can help harden and stabilize the localized areas.

[0024] Depending on the geometry and the intended purpose of the component, the regular arrangement of the micro-dimples may extend over substantially the entire sheet metal surface of the sheet metal part of the component, for example over more than 80% or 90% of the sheet metal surface, or the arrangement of the micro-dimples may be provided only in one or several defined local areas of the surface of the sheet metal part of the component, in particular in these areas with increased stiffness requirements.

[0025] The inventors have found that the stiffness of the component can be reliably increased when the size of the micro-dimples is chosen so that each micro-dimple in one metal sheet surface creates a corresponding small "micro-protrusion" on the opposite metal sheet surface. Therefore, according to a preferred embodiment of the invention, a regular arrangement of micro-protrusions is provided on a metal sheet surface of the metal sheet portion, which is opposite to the metal sheet surface provided with the regularly arranged micro-dimples, each micro-protrusion corresponding in position and form to one of the micro-dimples.

[0026] In the case where the enamel layer is provided on the surface of the metal plate provided with micro-protrusions, preferably, the enamel layer also completely covers and hides these micro-protrusions so that the outer surface of the resulting component is flat and smooth.

[0027] In order to ensure a uniform increase in stiffness over the intended area, the micro-dimples may be arranged in the form of a regular two-dimensional grid, in particular in the form of a rectangular, square or hexagonal grid.

[0028] When both opposing sheet metal surfaces of a sheet metal portion of a component are provided with a regular arrangement of micro-dimples as defined above, more uniform bending properties and higher stiffness may be obtained.

[0029] Preferably, the micro-dimples on the two opposing metal sheet surfaces are arranged in a staggered configuration relative to each other, particularly when each micro-dimple on one metal sheet surface produces a corresponding micro-protrusion on the opposing surface, so that each metal sheet surface is provided with a regular pattern of both micro-dimples and micro-protrusions.

[0030] A good compromise between stiffness properties and surface smoothness can be obtained when the depth of the micro-dimples is 40% to 100% of the thickness of the metal sheet.

[0031] However, deeper indentations should not be excluded. For example, the depth of the micro-indentation can be up to 200%, in particular up to 150% and preferably up to 120% of the sheet metal thickness of the sheet metal portion, even though in some cases this means that the micro-indentation is more visible and may not be completely covered or filled in the case of enameled parts.

[0032] Since the micro-dimples are produced during the pressing or embossing process, the micro-dimples should taper towards the bottom so that the component can be easily removed from the corresponding pressing tool. The shape of the micro-dimples can be, for example, a cone, such as a circular or elliptical cone, or a pyramid or a spherical cap, in particular the negative shape of a hemisphere, all of which can be easily realized with a small punch of corresponding shape provided on the pressing tool.

[0033] The present invention is particularly applicable to ovens, such as thermal ovens, non-thermal ovens, steam ovens and microwave ovens, but may also be applicable to other household appliances, such as washing machines, dishwashers and the like.

[0034] In particular, the household appliance may be an oven and the component may be selected from the group consisting of: a cavity, a front frame, a fan cover, an oven accessory, and an outer housing component.

[0035] The oven accessory may be, for example, a baking tray or a frying pan, and the outer housing part may be, for example, a bottom panel, a side panel, a rear panel, a top panel or a component carrier.

[0036] According to another aspect of the invention, the object is solved by a pressing tool comprising two opposing pressing clips, such as a punch and a die, which are configured to cooperate to form a component of a household appliance, in particular a sheet metal part of a component according to any of the preceding claims, wherein at least one of the pressing clips comprises a clip surface portion, which is provided with a regular arrangement of protruding micro-stampings, each micro-stamping having a height perpendicular to the surface portion, which is not less than 40% of the sheet metal thickness of the sheet metal part of the component formed in the tool, and each micro-stamping preferably has a dimension along the surface portion, which is not greater than ten times the sheet metal thickness, more preferably not greater than five times, two times or one times the sheet metal thickness.

[0037] Similar to the term "micro-protrusion", the term "micro-stamping" may be understood to relate to small stampings, i.e. stampings having dimensions along portions of the clip surface not greater than 1 cm, preferably in the order of a few millimeters, below 5 mm or even below 1 mm.

[0038] In particular or as an alternative, considering that the metal sheet thickness of the metal sheet portion of the component is typically in the range from 0.3 mm to 0.8 mm, the height h of the micro-stamping can be equal to or greater than 0.012 mm (= 0.4*0.3 mm), and the size of the micro-stamping along the surface portion of the clip can be equal to or less than 8 mm (= 10*0.8 mm), 4 mm, 1.6 mm (= 2*0.8 mm) or 0.8 mm.

[0039] In this pressing tool, both the overall three-dimensional form of the component and the micro-indentations can be produced in a single pressing process. By producing these micro-indentations, the material is also stressed and the structure is strengthened without having obvious macroscopic protrusions and discontinuous surfaces.

[0040] Some or all structures for producing raised and curved structures provided in conventional pressing tools solely for the purpose of increasing component rigidity can be omitted in the pressing tool according to the present invention, since these raised or curved structures are effectively replaced by the micro-dimples of the present invention.

[0041] Depending on the areas of the final component that require reinforcement, micro stampings may be provided over the entire area of ​​the component or only in limited areas.

[0042] If micro-dimples are introduced as part of a pressing step in the creation of a component as described above, further requirements of the tooling may determine which of the opposing metal sheet surfaces the micro-dimples should be applied to.

[0043] Preferably, the pressing clip opposite to the pressing clip provided with regularly arranged micro-stampings may include regularly arranged micro-recesses, each micro-recess corresponding to one of the micro-stampings in form and position, so that the sheet displaced by each micro-stamping can be accommodated in the corresponding micro-recess.

[0044] Alternatively, a pressing clip opposite to a pressing clip having regularly arranged micro-stampings may include a covering layer made of an elastic material, which is arranged in those areas of the pressing clip surface opposite to the micro-stampings when the pressing clips move toward each other, and wherein the covering layer is configured to be elastically deformed by the metal sheet material displaced by the micro-stampings.

[0045] The individual micro-stampings or “points” can, for example, have the form of a cone (for example a circular or elliptical cone), a pyramid or a spherical cap, in particular a hemisphere.

[0046] According to yet another aspect of the invention, the object is solved by a method for manufacturing a component for a household appliance, in particular for a component according to the invention as defined above, the method comprising the following steps:

[0047] Provide metal sheet,

[0048] pressing the sheet metal to form a sheet metal portion of the component, and

[0049] An arrangement of micro-dents is produced on at least one metal sheet surface of the metal sheet portion, each micro-dent having a depth perpendicular to the metal sheet surface, the depth being not less than 40% of the metal sheet thickness of the metal sheet portion, and each micro-dent preferably having a size along the metal sheet surface, the size being not greater than ten times the metal sheet thickness, preferably not greater than five times, two times or one times the metal sheet thickness.

[0050] The micro-dimples may be introduced during the pressing step, in which the overall macroscopic form of the component is also defined, or they may be introduced in a separate step, either before or after the step of pressing the metal sheet.

[0051] According to a preferred embodiment, the method further comprises the step of providing an enamel layer on at least one surface of the component, preferably on the surface provided with the arrangement of micro-dimples.

[0052] In order to obtain a smooth surface, the resulting enamel layer may be arranged such that it partially or completely fills the micro-indentations and preferably also partially or completely covers and hides any micro-protrusions (if provided).

[0053] However, the invention is also applicable to non-enameled parts, for example chassis parts (such as top or back panels), made of materials such as galvanized or micro-alloyed steel sheets, for example DX52 or HX300LAD.

[0054] In conventional components, in which the required stiffness is achieved by large embossed or curved structures, the thickness of the component can be locally increased to such an extent that, for example, laser cutting of the component on such structures becomes difficult or impossible.

[0055] Since this problem is eliminated when the stiffness of the component is increased by a regular arrangement of micro-dimples instead of conventional large embossing or curved structures, the method preferably comprises the step of cutting, preferably laser cutting, the component in the area where the arrangement of micro-dimples is provided.

[0056] Hereinafter, the present invention is explained in more detail with reference to some preferred embodiments of the present invention and comparative examples as illustrated in the accompanying drawings.

[0057] Figure 1 A comparative example of a conventional oven cavity top of the prior art is shown,

[0058] Figure 2 and Figure 3 Two embodiments of the invention are shown in the form of an oven cavity top having micro-dimples.

[0059] Figure 4 and Figure 5 shows photographs of another embodiment of the present invention at different magnification levels, specifically showing the geometric arrangement of micro-dimples,

[0060] Figure 6 is a simplified diagram showing the problem of placing cutouts in a conventional component.

[0061] Figure 7 is a simplified schematic top view of a portion of a component according to an embodiment of the present invention,

[0062] Figure 8 yes Figure 7 A part of the theme goes along the lines of Figure 7 A cross-sectional view along line VIII-VIII in FIG.

[0063] Fig. 9 yes Figure 7 A part of the theme goes along the lines of Figure 7 Cross-sectional view along line IX-IX in FIG.

[0064] Figures 10 to 13 The steps of the manufacturing method according to an embodiment of the present invention in a pressing tool according to an embodiment of the present invention are schematically shown.

[0065] Figures 14 to 17 The steps of a production method according to an embodiment of the present invention are schematically illustrated in an improved pressing tool according to another embodiment of the present invention.

[0066] Fig.18 A conventional baking tray known from the prior art is shown, and

[0067] Figures 19 to 21 Different examples of baking trays according to embodiments of the present invention are shown.

[0068] Corresponding features of different embodiments are denoted by the same reference numerals in the drawings showing these embodiments. Furthermore, for reasons of clarity, if there are several identical features in one figure, only some of these features are denoted by reference numerals. In a similar manner, not all features are denoted by reference numerals in each figure, but mainly those figures which are necessary or helpful for the explanation of the respective figure are included.

[0069] In addition, it should be noted that Figures 14 to 17 The drawings are simplified schematic illustrations which are mainly used to illustrate some of the principles of the invention and are particularly not drawn to scale unless otherwise indicated.

[0070] Figure 1 A top view of a conventional component 10 in the form of an oven cavity roof is shown, which is formed from sheet metal in a pressing or deep-drawing process and is provided with an enamel layer after forming.

[0071] Figure 1 The top of the oven cavity is generally rectangular, wherein, as Figure 1 The upper edge 10.1 of the illustrated component 10 corresponds to the upper rear edge of the oven cavity and as shown Figure 1 The lower edge 10.2 of the component 10 shown corresponds to the upper front edge of the oven cavity.

[0072] The component 10 comprises several functional structures F1 and F2 produced from a flat metal sheet by a pressing and / or stamping step.

[0073] Functional structure F1 is configured to support an oven light (not shown) in the slightly inclined wall portion F1.1 so that oven light introduced through opening F1.2 is directed downwardly and toward the rear wall of the oven cavity so as not to shine directly into the eyes of an operator opening the oven door.

[0074] Functional structure F2 relates to exhaust ports for introducing steam into the oven cavity.

[0075] In addition to these functional features, the component also comprises several large curved and / or embossed structures S which have the sole function of increasing the rigidity of the component so that it does not break or deform unintentionally, for example when it is subjected to high temperatures during the enameling step and / or during operation of the oven.

[0076] According to the invention, these structures S can be omitted if necessary, or they can be made smaller, because by providing a regular arrangement of micro-dimples in appropriate areas R, such as Figure 2 and Figure 3 The embodiment shown demonstrates that the required rigidity can be ensured. It should be noted that the micro-indentations are not visible in these figures due to their size and the fact that they can be covered by the enamel layer.

[0077] Figure 4 and Figure 5 Photographs at different magnification levels of a component 10 according to another embodiment of the invention are shown.The component 10 comprises a macro-embossed or curved structure F3, in particular in its edge region, and several holes H1-H2, obtained for example by punching.

[0078] Furthermore, the regular arrangement of micro-dimples 14 on the metal sheet surface 12s1 is clearly visible, the arrangement extending substantially over the entire surface of the component. The micro-dimples are arranged in a square grid pattern. Furthermore, a similar pattern of micro-protrusions 15 is provided on the surface 12s1 in a staggered configuration relative to the pattern of micro-dimples 14, thereby generally creating a central square pattern of micro-dimples 14 and micro-protrusions 15, which is Figure 5 The most clearly visible.

[0079] As shown, the size of the micro-dimples may in particular be of the same order of magnitude as the thickness of the sheet metal portion of the component.

[0080] Figure 6 is a schematically simplified view of a conventional component 10 including a macro-embossed or curved structure F4 to obtain the desired component stiffness. A cutout H3, obtained, for example, by laser cutting, may be provided in a planar portion of the structure as shown, but providing such a cutout in the area indicated by H4 may not be possible or may at least require that the cutout be obtained prior to the embossing step that produces the structure F4.

[0081] However, in Figure 7 In the component according to the invention shown, in which the required stiffness is imparted by the regular arrangement of micro-indentations and no macroscopic bending or embossing structures are required, incisions can be provided at any desired positions even after the micro-protrusions have been provided, such as indicated by way of example in the area shown by the dotted line and marked as H5.

[0082] Figure 7 is a simplified schematic top view of a portion of a component according to an embodiment of the present invention, and Figure 8 yes Figure 7 A part of the theme goes along the lines of Figure 7 A cross-sectional view taken along line VIII-VIII in FIG. 1 , and Fig. 9 yes Figure 7 A part of the theme goes along the lines of Figure 7 Cross-sectional view along line IX-IX in FIG.

[0083] and Figures 4 to 5 Similarly, in this embodiment, micro-dimples 14 (shown as continuous lines) and micro-protrusions 15 (shown as dashed lines) are also provided in two square grid patterns that are staggered relative to each other.

[0084] like Figure 8 and Fig. 9 As shown, the micro-protrusions 15 on the metal sheet surfaces 12s1, 12s2 are produced by micro-dimples 14 provided on the respective opposing metal sheet surfaces 12s2, 12s1. Furthermore, in the example shown, the micro-dimples 14 are substantially hemispherical in shape.

[0085] According to the present invention, the depth d of each micro-dimple 14 perpendicular to the metal sheet surface 12s1 and the metal sheet thickness t of the metal sheet portion 12 are related by the following relationship:

[0086] d≥0.4·t

[0087] Furthermore, according to the present invention, the dimensions l, w (ie length and width) of each micro-dimple 14 along the metal sheet surface 12s1 are not greater than 1 cm, preferably in the order of a few millimeters, lower than 5 mm or even lower than 1 mm.

[0088] According to a preferred embodiment, the dimensions l, w of each micro-dimple 14 along the metal sheet surface 12s1 are related to the metal sheet thickness t by the following relationship;

[0089] l≤10·t and w≤10·t

[0090] and preferably by

[0091] l≤2·t and w≤2·t

[0092] In addition, when set Figure 8 The distance D between any two adjacent micro-dimples 14 in the same metal sheet surface shown may be greater than the dimensions l, w of these micro-dimples 14 in at least one direction, preferably in all directions along the metal sheet surface 12. In this context, it should be noted that the distance D is to be understood as the dimension of the planar portion of the metal sheet surface 12s1 extending between adjacent micro-dimples 14, such as Figure 8What is shown.

[0093] Figures 10 to 13 The subsequent steps of a method according to an exemplary embodiment of the invention using a pressing tool 20 likewise according to an exemplary embodiment of the invention are illustrated in a schematically simplified manner.

[0094] First, if Fig.10 As shown, a metal sheet 11 is provided and arranged between opposing pressing jaws 21 of a pressing tool 20 .

[0095] like Fig.11 As shown, the metal sheet 11 is then pressed between pressing jaws 21 in order to form the metal sheet portion 12 of the component 10 .

[0096] Hemispherical micro-stampings 24 can be arranged in a regular arrangement on the two pressing clip surfaces 21s to produce micro-dents 14, and the material of the metal sheet 11 displaced by these micro-stampings 24 is accommodated in the corresponding micro-depressions 25 arranged on the corresponding other pressing clip surfaces 21s, so that the micro-protrusions 15 are regularly arranged on the two metal sheet surfaces 12s1, 12s2 of the metal sheet part 12 of the component 10.

[0097] It should be noted that the pressing jaws of all pressing tools shown herein typically include additional larger protrusions and / or recesses that are used to give the metal sheet portion 12 of the component 10 its overall three-dimensional shape, but for simplicity reasons these larger structures are not shown here.

[0098] Then, if Fig.12 The illustrated metal sheet portion 12 is provided with an enamel layer 16 on one of its surfaces 12s1, which enamel layer partially or even completely fills the micro-indentations 14 and partially or even completely covers the micro-protrusions 15 on this surface 12s1, as shown. Fig.13 As shown. Both conventional and direct enameling processes can be used.

[0099] Figures 14 to 17 A similar manufacturing method using a slightly different pressing tool 20 is shown in . Fig.14 and Fig.15 The pressing tools and Fig.10 and Fig.11 The main difference of the pressing tool is that only the upper pressing jaw 21 is provided with an arrangement of micro-stampings 24, instead of corresponding micro-recesses, and a covering layer 28 made of elastic material (such as rubber) is provided on the surface of the lower pressing jaw 21, wherein, as Fig.15 As shown, when the pressing jaws 21 are pressed together, the layer 28 is elastically deformed due to the material of the metal sheet 11 being displaced by the micro-stamping 14 .

[0100] Of course, each of the two press jaws includes both micro-stampings and resilient cover regions in a suitable arrangement to provide an arrangement of micro-dimples and micro-protrusions to both sheet metal surfaces of the component formed in the press tool.

[0101] Fig.18 A conventional component 10 in the form of a rectangular baking tray known from the prior art is shown. The edge region of the component 10 is bent in the usual manner so as to form a peripheral flange F5 as a functional feature.

[0102] Furthermore, large curved structures S1 and S2 are provided in the food supporting area in order to increase the rigidity of the baking tray and prevent it from breaking when used at high temperatures.

[0103] Fig.19 A component 10 according to an embodiment of the present invention is shown. Fig.18 The main difference of the example of is that, in addition to the large curved structures S1 and S2, a regular arrangement of micro-dimples as described above is provided in a region R which in this embodiment has the form of a rectangular ring.

[0104] Due to the micro-dimples, the stiffness of the component 10 is further increased, so that the disc can be used at even higher temperatures and / or can withstand even heavier loads.

[0105] Due to the micro-dents except for structures S1 and S2, Fig.18 The overall material thickness can also be reduced compared to conventional examples while maintaining component stiffness.

[0106] Fig. 20 and Fig.21 Further examples of different regions R are shown where a regular arrangement of micro-dimples may be provided on a baking tray. Fig.19 In contrast, the larger curved structures S1 , S2 are not present in these embodiments, as they are effectively replaced by micro-dimples.

[0107] Furthermore, it is also possible that the entire food supporting area of ​​the pan receives micro-dimples in order to increase its rigidity for accommodating heavier foods.

[0108] In general, the invention allows obtaining components formed from sheet metal for domestic appliances such that these components meet corresponding rigidity requirements while keeping the surface of the components as flat and smooth as possible or desired.

Claims

1. A component (10) of a household appliance, in, The metal plate portion (12) of the component (10) is formed by a metal plate (11), and is characterized in that regularly arranged micro-dents (14) are provided on at least one metal plate surface (12s1, 12s2) of the metal plate portion (12), and each micro-dent (14) has a depth (d) perpendicular to the metal plate surface (12s1, 12s2), and the depth is not less than 40% of the metal plate thickness (t) of the metal plate portion (12).

2. The component (10) according to claim 1, in, The dimension of each micro-dimple (14) in at least one direction along the metal plate surface (12s1, 12s2) is no greater than ten times the thickness (t) of the metal plate, preferably no greater than five times the thickness (t) of the metal plate, more preferably no greater than two times and most preferably no greater than one times.

3. A component (10) according to claim 1 or 2, in, The distance between any two adjacent micro-dimples (14) in the same metal plate surface (12s1, 12s2) is greater than the size of these adjacent micro-dimples in at least one direction along the metal plate surface (12s1, 12s2).

4. A component (10) according to any one of the preceding claims, Further comprising at least one enamel layer (16), which is preferably disposed on the metal sheet surface (12s1) provided with the arranged micro-dimples (14) and which even more preferably completely fills the micro-dimples (14).

5. A component (10) according to any one of the preceding claims, in, Regularly arranged micro-protrusions (15) are provided on the metal plate surface (12s2, 12s1) of the metal plate portion (12), which is opposite to the metal plate surface (12s1, 12s2) provided with regularly arranged micro-dimples (14), and each micro-protrusion (15) corresponds to one of these micro-dimples (14) in position and form.

6. A component (10) according to any one of the preceding claims, wherein The micro-dimples (14) are arranged in the form of a regular two-dimensional grid, in particular in the form of a rectangular, square or hexagonal grid.

7. A component (10) according to any one of the preceding claims, in, Each of the two opposite metal plate surfaces (12s1, 12s2) of the metal plate portion (12) is provided with an arrangement of micro-dents (14), each micro-dent (14) having a depth (d) perpendicular to the associated metal plate surface (12s1, 12s2), the depth being not less than 40% of the thickness (t) of the metal plate, and each micro-dent preferably having a dimension (l, w) along the associated metal plate surface (12s1, 12s2) being not greater than ten times the thickness (t) of the metal plate, more preferably not greater than five times, two times or one times the thickness (t) of the metal plate.

8. The component (10) according to claim 7, in, The arranged micro dimples (14) provided on the two opposing metal sheet surfaces (12s1, 12s2) are arranged in a staggered configuration relative to each other.

9. A component (10) according to any one of the preceding claims, wherein The depth (d) of the micro-dents (14) is not more than 200% of the thickness (t) of the metal sheet, in particular not more than 150%, preferably not more than 120%, and more preferably not more than 100% of the thickness (t) of the metal sheet.

10. A component (10) according to any one of the preceding claims, wherein These micro-indentations (14) have the negative shape of a cone or a pyramid or a spherical cap, in particular a hemisphere.

11. Component (10) according to any of the preceding claims, in particular according to claim 4, wherein The household appliance is an oven, and wherein the component (10) is selected from the group consisting of: a cavity, a front frame, a fan cover, an oven accessory and a housing component.

12. A pressing tool (20) comprising two opposing pressing jaws (21) configured to cooperate in order to form a sheet metal portion (12) of a component (10) of a household appliance, in particular a component according to any one of the preceding claims, It is characterized in that At least one of these clips (21) includes a clip surface portion (21s), which is provided with regularly arranged protruding micro-stampings (24), each micro-stamping having a height (h) perpendicular to the clip surface portion, which is not less than 40% of the metal sheet thickness (t) of the metal sheet portion (12) formed in the tool (20), and each micro-stamping preferably has a dimension (L) along the clip surface portion (21) that is not greater than ten times the metal sheet thickness (t), more preferably not greater than five times, two times or one times the metal sheet thickness (t).

13. The pressing tool (20) according to claim 10, wherein: The pressing clip (21) opposite to the pressing clip (21) provided with regularly arranged micro-stampings (24) comprises regularly arranged micro-dimples (25), each micro-dimple (25) corresponding in form and position to one of these micro-stampings (24), Or wherein the pressing clip (21) opposite to the pressing clip (21) provided with the regularly arranged micro-stampings (24) comprises a covering layer made of an elastic material.

14. A method for manufacturing a component (10) for a household appliance, in particular a component according to any one of claims 1 to 11, the method comprising the following steps: Providing a metal plate (11); pressing the metal sheet (11) to form a metal sheet portion (12) of the component (10); Characterized in that the method further comprises the following steps: An arrangement of micro-dents (14) is produced on at least one metal plate surface (12s1) of the metal plate portion (12), each micro-dent (14) having a depth (d) perpendicular to the metal plate surface (12s1, 12s2), the depth being not less than 40% of the metal plate thickness (t) of the metal plate portion (12), and each micro-dent preferably having a dimension (l, w) along the metal plate surface (12s1, 12s2) being not greater than ten times the metal plate thickness (t), preferably not greater than five times, two times or one times the metal plate thickness (t).

15. The method according to claim 13, wherein: The arrangement of micro-dimples (14) is produced during the step of pressing the metal sheet (10), or wherein the arrangement of micro-dimples (14) is produced in a separate step before or after the step of pressing the metal sheet (10).

16. A method according to any one of the preceding method claims, Further comprising the steps of: An enamel layer (16) is provided on at least one surface (12s1) of the metal sheet portion (12), preferably on the surface provided with the arranged micro-dimples (14), most preferably in such a way that the enamel layer (16) completely fills the micro-dimples (14).

17. A method according to any one of the preceding method claims, Further included is the step of cutting, preferably laser cutting, the component (10) in the region (R) providing the arrangement of micro-dimples (14).

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