WATER-CONDUCTING HOUSEHOLD APPLIANCE AND METHOD FOR PRODUCING A WATER-CONDUCTING HOUSEHOLD APPLIANCE

Description

[0001] The present invention relates to a household dishwasher and a method for manufacturing such a household dishwasher.

[0002] In addition to a washing container, household dishwashers may have an additional liquid container attached to the washing container, such as a heat exchanger or a holder for heating pipes, which is thermally coupled to the washing container.

[0003] The document DE 10 2011 086 788 A1 discloses a water-conducting household appliance with a rinsing container on the outside of which a water-conducting component is arranged, wherein a liquid space of the water-conducting component is at least partially delimited by at least one side wall of the rinsing container, and wherein the water-conducting component is fastened to the rinsing container via at least one adhesive connection.

[0004] The document DE 10 2004 043 716 A1 discloses a method for fastening a driver made of plastic in a washing drum of a washing machine, wherein the driver(s) have at least two internal domes which have a hollow space extending along their center line and which point perpendicularly towards the casing sheet of the washing drum and serve to fasten the driver. A hole pattern is punched into the casing sheet of the laundry drum for each driver, corresponding to the arrangement of the domes of a driver, and the driver is placed on the casing sheet with its dome ends projecting beyond the contact surface of the driver to the casing sheet such that the dome ends penetrate the holes in the hole pattern. Counterholders are then inserted into the dome cavities from the opposite side, and hold-down devices are moved against the casing sheet from the fastening side.Heated forming dies are then moved from the fastening side against the dome ends until the dome ends have mushroom-shaped caps produced by the hot-forming process, with their hat brims resting on the outer areas of the sheet metal surrounding the holes. Finally, all forming dies, hold-down devices, and counter-holders are retracted in this order.

[0005] JP 2012 232531 A2 discloses a method for bonding a resin molded article and a metal molded article by irradiating the resin molded article with a laser beam from the resin molded article side. An adhesive film is disposed between the resin molded article and the metal molded article. The adhesive film is made of a resin composition containing a thermoplastic elastomer and a laser light absorber. The thermoplastic elastomer has a melting point and a melt viscosity of V10 at a temperature that is V10 higher than the melting point and 50°C higher than the melting point. When the melt viscosity is V50, V10 / V50 ≤ 10 is satisfied, and the laser light absorber is a nigrosine dye. The resin molded article may be made of a thermoplastic resin having a melting point, and the thermoplastic elastomer of the adhesive film may have a melting point lower than the melting point of the thermoplastic resin.The adhesive film may be non-sticky. The thermoplastic resin may be a polyester resin, and the metal molded body may be made of copper, phosphor bronze, stainless steel, magnesium, aluminum, and iron. Furthermore, the metal molded body may have a thermal conductivity of 50 W / mK or more.

[0006] Against this background, it is an object of the present invention to provide an improved household dishwasher and an improved method for manufacturing a household dishwasher.

[0007] Accordingly, a household dishwasher is proposed. The household dishwasher comprises a wall made of a metal material and forming part of a washing tub of the household dishwasher, and a device made of a plastic material provided on the wall. The device is firmly connected to the wall by means of a laser weld. Furthermore, the device has a fastening flange, which is firmly connected to the wall by means of the laser weld. Furthermore, the wall is provided with a surface structure in the area where the fastening flange of the device rests on the wall.

[0008] Because the unit is firmly attached to the wall using laser welding, the step of gluing the unit to the wall is eliminated. This allows the household dishwasher to be manufactured more cost-effectively.

[0009] The washing compartment of the household dishwasher preferably comprises a first wall, in particular a base, a second wall, in particular a ceiling, a third wall, in particular a rear wall, a fourth wall, in particular a first side wall, and a fifth wall, in particular a second side wall. The household dishwasher can comprise a plurality of devices provided on different walls of the washing compartment. The washing compartment of the household dishwasher can further comprise a door pivotably mounted thereon.

[0010] The wall is, in particular, a side wall of the washing compartment of the household dishwasher. The wall can be made, for example, of the material 1.4301, 1.4310, 1.4510, or 1.4016. The household dishwasher can have a plurality of such devices, which can be provided on different walls of the household dishwasher. However, the device can also be made, at least in sections, of a metal material. In particular, however, at least that area of ​​the device that is connected to the wall is made of the plastic material.The plastic material can be, for example, a polypropylene (PP), in particular a natural PP, a PP filled with a filler such as talc, for example PP Talc 20 (PPTD20) or, for example, PP Talc 30 (PPTD30), an acrylonitrile-butadiene-styrene copolymer (ABS), a polymethyl methacrylate (PMMA), a polyvinyl chloride (PVC), a polyoxymethylene (POM), a polyamide (PA), in particular a PA filled with glass fibers, for example PA 6.6 GF 20 or PA 6.6 GF 30, or a thermoplastic elastomer (TPE). Alternatively, other plastic materials can also be used. The device is preferably a plastic injection-molded component. This allows the device to be produced cost-effectively in large quantities.

[0011] The device preferably carries water. Therefore, the device can also be referred to as a water-conducting device. Examples of water-conducting devices are a heat exchanger, a water inlet, a water outlet, a pump sump, or the like. However, the device can also not carry water. In this case, the device can be, for example, a holder for a heating wire or a heating pipe. For example, the device can be designed as a half-shell into which heating wires and / or heating pipes are snapped or clipped. However, it is assumed below that the device carries water.

[0012] In a further development of the household dishwasher, in which the device is water-conducting, the household dishwasher comprises a wall which is made of a metal material, a water-conducting device provided on the wall which is made of a plastic material, and a liquid space which is delimited by the wall and the device, wherein the device is firmly connected to the wall by means of a laser welded connection.

[0013] Because the liquid space facing away from the device is only limited by the wall made of the metal material, heat transfer from the liquid space to a rinsing space provided on an inner side of the wall facing away from the device and vice versa can be significantly improved.

[0014] The mounting flange of the device has, for example, a width of 2 to 20 mm. The mounting flange of the device preferably extends completely around the device. The surface structuring of the wall can comprise a plurality of linearly arranged depressions. The depressions can be arranged horizontally, vertically, or diagonally. The surface structuring of the wall can also comprise a matrix-like or checkerboard-like arrangement of depressions that are differently oriented. The depressions can be straight, curved, circular, or have any other geometry.

[0015] According to one embodiment, the device is a heat exchanger, a water inlet or a holder for a heating wire or a heating pipe.

[0016] The device can also be any other water-carrying component of the household dishwasher. For example, the device can also be a water outlet, a pump sump, or the like.

[0017] According to a further embodiment, the device comprises a storage section and a functional section.

[0018] The storage section of the device is particularly designed to store water and / or rinsing solution. The storage section of the device is directly connected to the wall. The functional section of the device can, for example, comprise a plurality of water channels, valves, control elements, or other systems. The storage section of the device is preferably a component manufactured separately from the functional section. The storage section of the device and the functional section of the device can be firmly connected to one another. Alternatively, the storage section of the device and the functional section of the device can also be formed from a single material.

[0019] According to a further embodiment, the wall is made of a chromium or chromium-nickel steel.

[0020] In particular, the wall is a thin sheet. This means that the wall has a thickness of less than 1.3 mm, in particular approximately 0.35 to 0.5 mm. For example, the materials 1.4301, 1.4310, 1.4510, or 1.4016 can be used.

[0021] The washing compartment preferably comprises a first wall, in particular a base, a second wall, in particular a ceiling, a third wall, in particular a rear wall, a fourth wall, in particular a first side wall, and a fifth wall, in particular a second side wall. The household appliance can comprise a plurality of devices provided on different walls of the washing compartment. The washing compartment can further comprise a door pivotably mounted thereon.

[0022] Furthermore, a method for manufacturing a household dishwasher is proposed. The method comprises the steps of providing a wall made of a metal material and forming part of a washing compartment of the household dishwasher, and a device made of a plastic material, and arranging the device on the wall. The method according to the invention is characterized in that the device, which has a fastening flange, is firmly connected to the wall by means of a laser weld, and in that, in the region in which the fastening flange of the device will rest on the wall, a surface structuring is produced at least in sections before the device is arranged on the wall.

[0023] When the device is provided, it can be manufactured using a plastic injection molding process, for example. Laser welding of the device to the wall can be achieved, for example, by conduction welding or laser transmission welding.

[0024] In conduction welding, the laser beam melts the joining partners along the joint, with radiation intensities of up to 100 kW / cm² typically used. Since metals suitable for laser beams can have a reflectivity of up to 95%, depending on the incident wavelength, the intensity is not sufficient to create a vapor capillary (keyhole). The melts flow into each other and solidify to form a weld. Conduction welding is used to join thin-walled parts, for example, for corner welds on the visible edges of housings. Other applications can be found in electronics. The laser creates a smooth, rounded weld that requires no further finishing. Pulsed or continuous-wave solid-state lasers are suitable for these applications. In conduction welding, the energy reaches the workpiece solely through heat conduction. Therefore, the weld depth is only a few tenths of a millimeter to one millimeter.The thermal conductivity of the material limits the maximum weld depth. The weld width is always greater than the weld depth. If the heat cannot dissipate quickly enough, the processing temperature rises above the vaporization temperature. Metal vapor is generated, the penetration depth increases dramatically, and the process transitions to deep penetration welding. Thermal conduction welding is usually performed using the lap method with an overlap of at least 3 mm, preferably at least 4 mm.

[0025] Laser transmission welding is usually carried out using the overlap method with an overlap of at least 3 mm, preferably at least 4 mm. Two different welding partners are used. The upper welding partner, for example a plastic, is transparent to the laser wavelength used. The laser shines through it almost unhindered. Due to its transparency, it hardly heats up. The lower welding partner, for example a metal material such as the one mentioned above, must absorb the radiation. This can be achieved by adding absorbing particles (approximately 0.3% by weight of soot). This material absorbs the energy, begins to melt, and in the process transfers the resulting heat to the upper partner through thermal conduction. In order for the energy transfer and material contact to take place, both partners often have to be pressed together, or at least fit together precisely.By fusing the two materials together, a weld seam can be created. The welding energy should be selected so that the laser only penetrates approximately 60% of the workpiece. Lasering from both sides then ensures complete penetration. Excessive power should be avoided, as it can lead to metal damage. Efficient diode lasers are often used for this purpose; at the required low power levels, for example, 5 to 150 watts, they provide sufficient beam quality for this welding process.

[0026] In simultaneous welding, the entire weld seam is heated simultaneously. While a linear weld seam is easily achieved, radii in the weld seam can only be approximated by arranging the laser diodes in a row or must be formed using additional beam-shaping elements. To achieve the necessary homogeneous power density distribution across the entire weld seam, the individual laser elements must be arranged accordingly and controlled separately.

[0027] In a further development of the method, the device is water-conducting. The method then comprises the steps of providing a wall made of a metal material and a water-conducting device made of a plastic material, arranging the device on the wall to form a liquid space bounded by the wall and the device, and laser welding the device to the wall.

[0028] The surface structuring can comprise a plurality of linearly arranged depressions. The depressions can be arranged horizontally, vertically, or obliquely. The depressions can have any geometry. For example, the depressions can be straight, curved, wavy, or the like. The depressions can, for example, have a depth of 10 to 100 µm, preferably 15 to 90 µm, in particular 20 to 80 µm.

[0029] The mounting flange preferably extends completely around the device. The mounting flange can, for example, have a width of 2 to 20 mm. The mounting flange preferably rests flat against the wall.

[0030] According to one embodiment, the surface structuring is carried out using nanopulsed laser beams.

[0031] This surface structuring, supported by numerous tests, has the following key data: an average power of approximately 20 W, a surface power of approximately 0.2 cm² / s, a pulse frequency of 20 to 100 kHz, and a wavelength of 1064 nm. The matrix of the respective surface structuring has a power of 20 to 100%, a frequency of 20 to 80 kHz, and a constant feed rate of approximately 200 mm / s. The line spacing of the nanopulsed laser beams is approximately 0.12 mm.

[0032] Laser structuring during nanopulsed laser operation can be determined using laser scanning microscopy (LSM), both in 2D and 3D. Laser structuring is generally characterized by material ejections and structure depths, and possibly also by embedding agents. Material ejections preferably have an average spacing in the range of 30 to 120 µm, preferably 40 to 110 µm, in particular 50 to 100 µm. Structure depths, on the other hand, have an average depth of 10 to 100 µm, preferably 15 to 90 µm, in particular 20 to 80 µm.

[0033] A pulsed laser is a laser that does not emit light continuously, but rather operates in a pulsed manner, meaning that the light is emitted in time-limited portions. When the surface structuring is applied, the wall is melted at least in sections. During melting, the material of the wall evaporates at least partially and / or molten material is ejected from the recess. This creates elevations on the sides of the recess. The surface structuring in particular has undercuts into which the molten plastic material of the device can flow. This creates a positive connection between the device and the wall. A positive connection is created by the interlocking or engaging behind of at least two connection partners, in this case the recesses and the plastic material of the device.

[0034] Alternatively, surface structuring can also be carried out using continuous wave laser beams.

[0035] This surface structuring, supported by numerous tests, has the following key data: a maximum power of 400 W, a surface power of approximately 0.84 cm² / s, and a wavelength of 1070 nm. The matrix of the respective surface structuring has a power of 100 to 400 W, one to five passes, and a constant feed rate of approximately 10,000 mm / s. The line spacing of the continuous-wave laser beams is approximately 0.12 mm.

[0036] Laser structuring in continuous-wave laser operation can be observed using laser scanning microscopy (LSM), both in 2D and 3D. Laser structuring is generally characterized by material ejections and structure depths, and possibly also by embedding materials. Material ejections preferably have an average spacing in the range of 30 to 120 µm, preferably 40 to 110 µm, in particular 50 to 100 µm. Structure depths, on the other hand, have an average depth of 10 to 100 µm, preferably 15 to 90 µm, in particular 20 to 80 µm.

[0037] Further possible implementations of the household dishwasher and / or the method also include combinations of features or embodiments described above or below with respect to the exemplary embodiments that are not explicitly mentioned. In this case, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the household dishwasher and / or the method.

[0038] Further advantageous embodiments and aspects of the household dishwasher and / or the method are the subject of the dependent claims and the exemplary embodiments of the household dishwasher and / or the method described below. The household dishwasher and / or the method are explained in more detail below using preferred embodiments with reference to the accompanying figures.

[0039] It shows Fig. 1 is a schematic perspective view of an embodiment of a household dishwasher; Fig. 2 is a schematic sectional view of the household dishwasher according to Fig. 1 ; Fig. 3 the detailed view III according to Fig. 2 ; Fig. 4 the detailed view IV according to Fig. 3 ; and Fig. 5 a schematic block diagram of an embodiment of a method for manufacturing the household dishwasher according to Fig. 1 .

[0040] In the figures, identical or functionally equivalent elements have been given the same reference numerals unless otherwise stated.

[0041] The Fig. 1shows a schematic perspective view of an embodiment of a household dishwasher 1. The household dishwasher 1 comprises a washing container 2, which can be closed by a door 3, in particular in a watertight manner. For this purpose, a sealing device can be provided between the door 3 and the washing container 2. The washing container 2 is preferably cuboid-shaped. The washing container 2 can be arranged in a housing of the household dishwasher 1. The washing container 2 and the door 3 can form a washing chamber 4 for washing dishes.

[0042] Door 3 is in the Fig. 1shown in its open position. The door 3 can be opened or closed by pivoting about a pivot axis 5 provided at a lower end of the door 3. With the help of the door 3, a loading opening 6 of the washing compartment 2 can be closed or opened. The washing compartment 2 has a plurality of walls 7 to 11. The washing compartment 2 preferably comprises a first wall 7, in particular a base, a second wall 8, in particular a ceiling, arranged opposite the first wall 7, a third wall 9, in particular a rear wall, arranged opposite the closed door 3, a fourth wall 10, in particular a first side wall, and a fifth wall 11, in particular a second side wall, arranged opposite the fourth wall 10.

[0043] The first wall 7, the second wall 8, the third wall 9, the fourth wall 10, and the fifth wall 11 can be made, for example, from a stainless steel sheet. For example, a stainless steel with the material identification number 1.4301, 1.4310, 1.4510, or 1.4016 can be used as the material. Alternatively, the first wall 7 can be made of a plastic material. The rinsing container 2 can be arranged on a base support (not shown). The base support is preferably a plastic component. In particular, the base support can be a plastic injection-molded component.

[0044] The household dishwasher 1 further comprises at least one dishware receptacle 12 to 14. Preferably, several, for example three, dishware receptacles 12 to 14 can be provided, wherein the dishware receptacle 12 can be a lower dishware receptacle or a lower basket, the dishware receptacle 13 can be an upper dishware receptacle or an upper basket, and the dishware receptacle 14 can be a cutlery drawer. Fig. 1 As further shown, the dishware receptacles 12 to 14 are arranged one above the other in the washing container 2. Each dishware receptacle 12 to 14 can be moved either into or out of the washing container 2. In particular, each dishware receptacle 12 to 14 can be pushed into the washing container 2 in an insertion direction E (arrow) and pulled out of the washing container 2 in an extension direction A (arrow) opposite to the insertion direction E (arrow).

[0045] The Fig. 2shows a schematic sectional view of the household dishwasher 1. The household dishwasher 1 comprises a device 15, which can be provided on one of the walls 7 to 11. Preferably, the device 15 is water-conducting. Therefore, the device 15 can also be referred to as a water-conducting device. Examples of water-conducting devices 15 are a heat exchanger, a water inlet, a water outlet, a pump sump or the like. However, the device 15 can also not conduct water. In this case, the device 15 can, for example, be a holder for a heating wire or a heating pipe. For example, the device 15 can be designed as a half-shell into which heating wires and / or heating pipes are snapped or clipped. However, it is assumed below that the device 15 is water-conducting.

[0046] Preferably, the device 15 is provided on the fourth wall 10 or on the fifth wall 11. Furthermore, the device 15 can also be provided on the third wall 9 or on the second wall 8. Several devices 15 can also be provided. Fig. 2 However, only one device 15 is shown, which is provided on the fifth wall 11.

[0047] The device 15 can, as previously mentioned, be, for example, a heat exchanger or a water inlet. If the device 15 is a heat exchanger, it can comprise a storage section 16 and a functional section 17. The storage section 16 of the device 15 and the functional section 17 of the device 15 can be separately manufactured components that are firmly connected to one another. Alternatively, the storage section 16 of the device 15 and the functional section 17 of the device 15 can also be formed from a single piece of material.

[0048] The storage section 16 of the device 15 is configured to store water and / or wash liquor. The functional section 17 of the device 15 can comprise, for example, channels, valves, various systems, or the like. The device 15 can be configured to store energy, in particular thermal energy, for example in the form of heated water. This thermal energy can be transferred to the washing container 2. Conversely, energy can also be transferred from the washing container 2 to the device 15.

[0049] The device 15 and in particular the storage section 16 of the device 15 are preferably made of a plastic material. Examples of suitable plastic materials include polypropylene (PP), in particular natural PP, PP filled with a filler such as talc, for example PP Talc 20 (PPTD20) or PP Talc 30 (PPTD30), acrylonitrile-butadiene-styrene copolymer (ABS), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyoxymethylene (POM), polyamide (PA), in particular glass fiber-filled polyamide, such as PA 6.6 GF 20 or PA 6.6 GF 30, or a thermoplastic elastomer (TPE). The device 15 can also be made of various plastic materials. Furthermore, the device 15 can also be made at least partially of a metal material. For example, a stainless steel with the material identification number 1.4301, 1.4310, 1.4510 or 1.4016 can be used as a metal material.

[0050] The storage section 16 of the device 15 is designed in the form of a half-shell or trough, which is open in the direction of the fifth wall 11. To connect the storage section 16 of the device 15 to the fifth wall 11, the device 15 comprises a mounting flange 18, which preferably completely surrounds the storage section 16 of the device 15 and in particular the device 15. The mounting flange 18 can have a width of approximately 5 to 20 mm.

[0051] The mounting flange 18 is made entirely of a plastic material. The device 15, and in particular the storage section 16 of the device 15, is connected by means of a laser weld 19 (see Fig. 3) is firmly and watertightly connected to the fifth wall 11. The device 15 and in particular the storage section 16 of the device 15 thus encloses a liquid chamber 20 with the fifth wall 11. This means that the liquid chamber 20 is only separated from the washing chamber 4 by the fifth wall 11, i.e. only by the metal material of the fifth wall 11. This ensures particularly good heat transfer from the liquid chamber 20 to the washing chamber 4 and vice versa. This makes it possible to achieve optimal diffusion conditions between the liquid chamber 20 and the washing chamber 4. This makes it possible to significantly improve the energy balance of the household dishwasher 1 compared to an arrangement in which a plastic layer is provided between the liquid chamber 20 and the fifth wall 11.

[0052] The functional section 17 of the device 15 comprises a half-shell made of a plastic material, which contains the aforementioned channels, valves, and / or other systems. The functional section 17 of the device 15 can be sealed using a film and a laser welding process. Here, the use of the film also improves the diffusion conditions and thus the energy balance of the household dishwasher 1.

[0053] The previously explained advantages can also be utilized in the case where the device 15 is a water inlet. Furthermore, the device 15 can also be designed as a composite component, in which the functional section 17 of the device 15 is first sealed using the aforementioned foil, and then the storage section 16 of the device 15 is joined directly to the fifth wall 11 using the laser welding process, in particular using a short-pulse laser.

[0054] The rinsing tank 2, and in particular the fifth wall 11, are made of chrome steel or chrome-nickel steel. In particular, the fifth wall 11 is a thin sheet. Thin sheets are sheets with a thickness of less than 3 mm. To achieve a reliable and permanent connection of the fastening flange 18 to the fifth wall 11, the fifth wall 11 is provided with a surface structuring 21 in the area of ​​the laser-welded connection 19 (see Fig. 3 and Fig. 4). The surface structuring 21 is introduced, for example, with the aid of a nanopulsed laser into an outer side 22 of the fifth wall 11 facing away from the rinsing chamber 4. The depth of the surface structuring 21 is selected such that, with the aid of inert gas, no oxidation colors occur on an inner side 23 of the fifth wall 11. The surface structuring 21 serves, on the one hand, to enlarge the surface area of ​​the outer side 22, and furthermore, the surface structuring 21 preferably forms undercuts into which the molten plastic material of the fastening flange 18 flows and forms a positive connection with the undercuts.

[0055] The surface structuring 21 can comprise a plurality of recesses 24 arranged in rows, of which in the Fig. 3 and Fig. 4 However, only two are provided with a reference symbol. The recesses 24 can be aligned in the direction of the Fig. 3 and Fig. 4be arranged horizontally. However, the recesses 24 can also be positioned vertically or obliquely. The recesses 24 can also be arranged differently from the illustration in the Fig. 3 and Fig. 4 also have a curved, circular, or any other geometry. The surface structuring 21 can also include checkerboard-like or matrix-like recesses 24 with different orientations. This can further improve the connection between the mounting flange 18 and the surface structuring 21.

[0056] For example, the materials 1.4301, 1.4310, 1.4510, or 1.4016 can be used for the fifth wall 11, but also for the other walls 7 to 10. The recesses 24 of the surface structuring 21 can, for example, have a depth of 10 to 100 µm, preferably 15 to 90 µm, in particular 20 to 80 µm. Elevations can be formed laterally along the recesses 24, which are created by remelting and ejecting the material of the fifth wall 11 from the recesses 24.

[0057] The Fig. 5shows a schematic block diagram of a method for manufacturing the household dishwasher 1. In a step S1, the washing compartment 2, and in particular one of the walls 7 to 11 of the washing compartment 2, is provided. The walls 7 to 11 are made of a metal material, in particular of the material 1.4301, 1.4310, 1.4510 or 1.4016, and the walls 7 to 11 are part of a washing compartment 2 of the household dishwasher 1. In step S1, the device 15 is also provided, which is made at least in sections of a plastic material. The device 15 can be manufactured, for example, in step S1 using a plastic injection molding process.

[0058] In a step S2, the device 15 is arranged on the wall 7 to 11 to form the liquid space 20. The liquid space 20 is bounded by the corresponding wall 7 to 11 and the device 15, in particular the storage section 16 of the device 15.

[0059] In a step S3, the device 15 having a fastening flange 18 is firmly connected to the corresponding wall 7 to 11 by means of a laser weld. In the area of ​​the wall 7 to 11 in which the fastening flange 18 of the device 15 will rest on the wall 7 to 11, a surface structuring 21 is created at least in sections on the wall 7 to 11 before the device is arranged S2 on the wall 7 to 11. A diode laser is preferably used for the welding process, with a feed speed of the laser significantly determining the power of the laser used. The device 15 is positioned relative to the corresponding wall 7 to 11 with the aid of a clamping device and pressed against it.

[0060] The laser welding of the device 15 to the wall 7 to 11 can be carried out, for example, using a laser transmission welding process. In this case, the fastening flange 18 has a high degree of transmission for the laser radiation in the range of the laser wavelength used. The laser radiation is then absorbed by the outer side 22, whereby the fastening flange 18 is melted at least in sections. Alternatively, the laser welding can also be carried out using thermal conduction joining. This allows the corresponding wall 7 to 11 to be heated, for example, from the inner side 23. The outer side 22 is then heated by thermal conduction such that the fastening flange 18 melts at least in sections.Before or during the arrangement of the device 15 on the corresponding wall 7 to 11 in step S2, the corresponding wall 7 to 11 is surface-structured at least in sections, as previously explained. Nanopulsed laser beams are preferably used for this purpose.

[0061] By eliminating the plastic wall between the liquid chamber 20 and the flushing chamber 4, heat transfer from the liquid chamber 20 to the flushing chamber 4 is significantly improved, and material savings are achieved by eliminating the plastic material. An expensive, energy-intensive butt welding process is eliminated.

[0062] The storage section 16 of the device 15 can be manufactured with the variant number one; the differentiation of the device 15 then occurs via the functional section 17 of the device 15. The greatest advantage of the device 15 being welded directly to the rinsing tank 2 lies in the significantly improved energy diffusion ratio and thus in the significantly improved energy balance. By eliminating the mirror welding, more cost-effective plastics with a better flow index can be used. The injection speed during injection molding and thus the production capacity can be increased, which can reduce investments. By eliminating the mirror welding process and using line laser welding for the film composite, better-flowing plastic can be used. Higher injection speeds are also possible here. Omitting the film likewise improves the diffusion ratios and thus the energy balance.Overall, there is a clear advantage in terms of material and process costs when the laser welding process is used. Reference symbols used

[0063] 1 Household dishwasher 2 Washing container 3 Door 4 Washing chamber 5 Pivot axis 6 Loading opening 7 Wall 8 Wall 9 Wall 10 Wall 11 Wall 12 Dishwasher receptacle 13 Dishwasher receptacle 14 Dishwasher receptacle 15 Fittings 16 Storage section 17 Functional section 18 Mounting flange 19 Laser welded joint 20 Liquid chamber 21 Surface structuring 22 Outside 23 Inside 24 Recess AExtraction direction (arrow) EInsertion direction (arrow) S1Step S2Step S3Step IIIDetail view IVDetail view

Claims

1. Household dishwashing machine (1), comprising a wall (7 to 11) which is made from a metal material and which is part of a washing container (2) of the household dishwashing machine (1), and a device (15) which is provided on the wall (7 to 11) and which is made from a plastic material, characterised in that - the device (15) is fixedly connected to the wall (7 to 11) by means of a laser weld connection (19) - the device (15) has a fastening flange (18) which is fixedly connected to the wall (7 to 11) by means of the laser weld connection (19), and - in the region in which the fastening flange (18) of the device (15) bears against the wall (7 to 11), the wall is provided with a surface structuring (21).

2. Household dishwashing machine (1) according to claim 1, characterised in that the device (15) is a heat exchanger, a water inlet or a holder for a heating wire or a heating pipe.

3. Household dishwashing machine (1) claim 2, characterised in that the device (15) comprises a storage portion (16) and a functional portion (17).

4. Household dishwashing machine (1) according to claim 1, 2 or 3, characterised in that the wall (7 to 11) is made from a chromium steel or chromium-nickel steel.

5. Method for producing a household dishwashing machine (1), comprising the steps: - providing (S1) a wall (7 to 11) which is made from a metal material and which is part of a washing container (2) of the household dishwashing machine (1), and a device (15) which is made from a plastic material, and - arranging (S2) the device (15) on the wall (7 to 11), characterised in that - the device (15) having a fastening flange (18) is fixedly connected (S3) to the wall (7 to 11) by means of a laser weld connection and - in the region of the wall (7 to 11) in which the fastening flange (18) of the device (15) will bear against the wall (7 to 11), before arranging (S2) the device (15) on the wall (7 to 11), a surface structuring (21) is at least partially produced thereon.

6. Method according to claim 5, characterised in that the surface structuring (21) is carried out by means of nano-pulsed laser beams.