Device for generating steam and household appliance comprising such a device

Abstract

A steam-generating device for a steam oven comprises a water storage chamber with a water inlet and outlet, and a heating chamber for water drawn from the storage chamber. The heating chamber has a steam outlet and a heating chamber inlet connected to the water outlet. A heating element for heating and evaporating the water within is located on the outside of the heating chamber. The water storage chamber is positioned laterally next to the heating chamber, and they are separated by a partition open at the bottom. The steam-generating device is wider than it is tall in a vertical direction perpendicular to the heating chamber and at least five times wider than it is thicker, thus being relatively flat. The heating element is located on the outside of the heating chamber on one of the flat sides of the housing.

Description

[0001] The invention relates to a device for generating steam, preferably for household appliances such as ovens or steam cookers, but also for washing machines, for example. The device comprises a water storage chamber and a heating chamber, in which a heating device for heating and evaporating water is arranged. Furthermore, the invention relates to a household appliance with such a device for generating steam, in particular an oven or steam cooker, possibly also a washing machine or dishwasher.

[0002] Such a device for generating steam is known from DE 10 2007 048 567 A1. It is designed as a type of circuit and has a water storage chamber on one side. This has a water inlet and a water outlet, which leads downwards like a line and then away to the side and upwards in a ring-like manner back into the water storage chamber. In the upwardly running right-hand area, a water line is formed from a different component, and two elongated heating devices are attached to the outside here. These heat the flowing water to such a high temperature that it can escape as steam at an upper end of the return line to the water storage chamber, which corresponds to a steam outlet. This design allows the water to circulate and thus be heated as it flows until steam forms.

[0003] US 2022 / 186 924 A1 discloses a device for generating steam, which comprises an upright water chamber. In a lower, narrower area, a flat heating element is provided on a lateral side wall to heat the water contained in the water chamber and generate steam, for example, for a steam oven. Above this, a somewhat wider chamber serves as the steam area, from which a steam outlet leads upwards. A grid-like partition wall is arranged within the steam area to calm bubbling boiling water and to prevent water droplets from being entrained by escaping steam to the steam outlet.

[0004] EP 2 309 910 B1 discloses a nozzle for a steam cleaner, which comprises a device for generating steam. This device also includes a heating chamber for generating steam from heated water.

[0005] EP 0 374 863 B1 discloses yet another device for generating steam, such as can be used, for example, in a steam oven. A water reservoir with a heating chamber and heating device is provided to generate steam for use in the steam oven. Task and solution

[0006] The invention is based on the object of creating a device mentioned above with which problems of the prior art can be eliminated and, in particular, it is possible to evaporate water quickly and energy-efficiently to generate steam and to be able to arrange or accommodate the device in an aforementioned household appliance.

[0007] This object is achieved by a device having the features of claim 1 and by a household appliance having the features of claim 10. Advantageous and preferred embodiments of the invention are the subject of the further claims and are explained in more detail below. Some of the features are described only for the device for steam generation or only for the household appliance. However, they are intended to be able to apply independently and independently of one another to both such a device and such a household appliance. The wording of the claims is incorporated into the content of the description by express reference.

[0008] The device for generating steam has a water storage chamber, which in turn has a water inlet and a water outlet. The water inlet is used to refill the water storage chamber with water, particularly from outside, either through a connected line with a valve or manually through a nozzle. The device also has a heating chamber in which water from the storage chamber is contained and heated to form steam. The heating chamber has a heating chamber inlet that is fluidly connected to the water outlet. In particular, the water outlet and heating chamber inlet can be virtually identical, for example, an opening in a wall. The heating chamber also has a steam outlet through which steam generated in the heating chamber can escape. A corresponding steam line leading to a specific location for the steam can then be connected to this steam outlet.The device also comprises a heating device arranged in the heating chamber. It serves to heat and evaporate water in the heating chamber. Advantageously, the heating device is an electric heating device, in particular with a resistance heating element that heats through contact heat or heats the water and causes it to evaporate.

[0009] According to the invention, the water storage chamber is arranged laterally next to the heating chamber. They therefore do not surround each other, or the heating does not surround the water. Furthermore, the device is wider in a direction of extension from the heating chamber to the water storage chamber than it is high in a vertical direction or in the vertical direction perpendicular thereto. The device is also at least 5 times wider in the horizontal direction than in a horizontal thickness direction perpendicular thereto. It can therefore be said that the device as a whole is advantageously flat on edge and wider than it is high. This configuration enables simple and space-saving integration of the device into an aforementioned household appliance, for example on an outer side, in particular on a rear side, of such a household appliance or a treatment chamber that is optionally thermally insulated from the outside, such as a muffle of a steamer or oven.Due to the overall flat design of the entire device and advantageously also of the heating chamber per se, there are at least one or actually two outer sides that are relatively large and can therefore be very well covered by a flat heating device for heating.

[0010] In a further embodiment of the invention, it can be provided that the water storage chamber and the heating chamber form a structural unit with a single common housing. This can be manufactured particularly advantageously by plastic injection molding, in particular in two or three parts. These individual parts can then be assembled to form the structural unit or housing. The heating device can then be arranged on it. By manufacturing it as a common structural unit, handling and in particular assembly to a household appliance are easier. Furthermore, electrical connections can also be made more easily, so that the device or structural unit only has a single connection to the outside, advantageously in the form of a multiple plug. This also makes final assembly with the household appliance easier, faster and more error-free.

[0011] In another possible embodiment of the invention, the aforementioned structural unit can have an outer cuboid shape, thus being relatively simple in design. The thickness can also be less than 20% of the width in the horizontal direction, for example, down to 5%. The flatter the heating chamber, the larger the area on one of the flat outer sides where a heating device can be arranged for heating purposes. Thus, the heating device can also be larger and more powerful.

[0012] In a further embodiment of the invention, it is advantageously possible for the water storage chamber and the heating chamber to be formed and separated from one another in one housing, i.e. a single common housing according to the aforementioned embodiment, by providing a housing partition. The housing itself can thus have a single internal volume, so to speak, and the division is effected by the housing partition arranged therein. The aforementioned water outlet of the water storage chamber can correspond to the heating chamber inlet of the heating chamber, wherein it can be formed particularly simply by an opening and / or by an interruption in the housing partition. This eliminates the need for complex lines, channels, or the like, which can increase manufacturing and assembly costs and pose the risk of leaks. All water that leaves the water storage chamber necessarily reaches the heating chamber.It can also be provided that only a single breakthrough or a single opening or interruption in the housing partition wall is provided between the water storage chamber and the heating chamber.

[0013] In a simple embodiment, which is not part of the invention, it can be provided that the structural unit is essentially formed by the water storage chamber and the heating chamber, both of which are open in themselves or are no longer subdivided and which are connected to one another. In this way, water can flow from the water storage chamber into the heating chamber, advantageously automatically or without any necessary effort. Neither the water storage chamber nor the heating chamber are subdivided again, thereby reducing the manufacturing and assembly effort. An aforementioned heating device can then advantageously cover an entire side or outer side of the heating chamber. In this way, a high heating output can be introduced into the water in the heating chamber. This heating device can act over a large area, at least over the largest part of the cross-section of the heating chamber.

[0014] In the invention, a separating partition wall is arranged within the heating chamber, which essentially subdivides the heating chamber once again. It is divided into two regions, each of which has at least two connecting channels for fluid communication. Thus, a connecting channel can particularly preferably be arranged in the upper region of the heating chamber, advantageously in the uppermost region. Here, the partition wall can have a corresponding opening and / or interruption, for example, similar to that described above for the housing partition wall.

[0015] The upper connecting channel is advantageously positioned above a typical water level for water in the device or assembly. This allows primarily or even exclusively steam to flow from one area to another through the upper connecting channel, with a steam outlet leading primarily from the other area. Another connecting channel can advantageously be provided in the lowest area of ​​the heating chamber, particularly advantageously as an opening or interruption in the partition wall. The other connecting channel should always run below the water level to ensure a constant flow of water.

[0016] The heating chamber is divided by means of an intermediate wall into, on the one hand, a heating zone, at or for which the heating device is arranged. The heating device can cover a side surface of the heating chamber or the heating zone of the heating chamber. The other zone is a steam zone, from which the aforementioned steam outlet branches off. Steam can also flow from the heating zone through an aforementioned upper connecting channel to the steam outlet, passing through the upper zone of the steam zone. In particular, it can be provided that no heating device is arranged in the steam zone. This can, for example, ensure that there is no simmering or boiling water below the steam outlet, which could otherwise eject small water droplets towards the steam outlet.

[0017] In the invention, the aforementioned steam zone is located between the water storage chamber and the heating zone. The water storage chamber and the heating zone are thus separated from each other by the steam zone. This allows the steam zone to form a kind of thermal insulation between the heating zone and the water storage chamber. This prevents excessive heat energy from the heating device from also flowing into the water storage chamber, which could potentially result in energy loss.

[0018] In an advantageous embodiment of the invention, the heating device is arranged on the outside of the heating chamber. The heating device is advantageously designed to be flat or planar. It can, in particular, cover at least 20% of the outer surface of the heating chamber or heating area. This is advantageously at least 30% to 40%, in particular at least 30% to 40%, of the outer surface of the heating area of ​​the heating chamber.

[0019] In a further embodiment of the invention, the heating chamber can have two flat outer sides facing each other. This is certainly possible with the aforementioned preferred embodiment of the heating device with a flat design. Advantageously, the heating device can be arranged on only one of the flat outer sides. The other flat outer side is then designed without a heating device or has no heating. Advantageously, this is the outer side facing functional units of the household appliance, such as an oven chamber or a treatment chamber.

[0020] One possible way of arranging the heating device on the housing or on the structural unit in the area of ​​the heating chamber is for an aforementioned outer side to have an opening or hole. This opening can be between 5% and 50% of the outer side of the heating device. The heating device then covers this hole, with the main advantage being that the heating device then comes into direct contact with the water in the heating area or on the heating chamber. This ensures rapid and efficient heating of the water. In this way, heat transfer between the heating device and the water in the heating chamber can be kept very low, at least over a significant or predominant area of ​​the heating device, in particular more than 60% of its area. The heating device should be large compared to the outer side in the area of ​​the heating chamber.

[0021] In an advantageous embodiment of the invention, the heating device is a thick-film heating device. This is manufactured by applying a thick-film heating element directly to a metallic heating substrate. The heating device and the heating substrate can be arranged on the outside of the heating chamber. While such thick-film heating devices or thick-film heating elements are more complex to manufacture, they offer a very good ratio of their own weight or mass to their heating output and heating surface. Due to the relatively lower energy requirement for their own heating, more heat can be applied to the water over a larger area.

[0022] In a further advantageous embodiment of the invention, the heating device can be a thick-film heating device, in which a thick-film heating element is advantageously applied directly to a mechanical heating carrier. Subsequently, the heating device can be arranged with the heating carrier on an outer side of the heating chamber, for example, as previously mentioned.

[0023] It is possible for the water inlet and / or the steam outlet to protrude upwards. In this case, it can be provided that the water inlet as well as the steam outlet protrude upwards. This can correspond to a housing as already described. In an advantageous development of the invention, the water inlet and / or steam outlet protrude upwards, especially because this facilitates the automatic rise of steam. The aspect of the upwardly protruding water inlet is considered less important; this is simply a good location for such a water inlet without having to worry about water running out again. The upward steam outlet has the advantage that steam can escape upwards and into a device without hindrance.

[0024] In an advantageous development of the invention, it is possible for a drainage outlet to lead from the water storage chamber. Similar to the steam outlet leading from the uppermost region of the water storage chamber and / or the heating chamber, it should lead from a lower region or a lowest point of the water storage chamber. This allows for as complete drainage as possible. This drainage outlet should not be confused with the water outlet provided according to the invention, which was described above and which connects the water storage chamber and the heating chamber to one another in a water-conducting manner. However, such a drainage outlet is not mandatory; any remaining water could also be evaporated by operating the heating device. The water storage chamber and heating chamber can also be dried in this way.

[0025] A household appliance according to the invention comprises a treatment chamber arranged in a housing of the appliance and the aforementioned steam generation device. The appliance and the steam generation device can be controlled via a single controller; a display or user interface can advantageously also be provided for this purpose. The steam generation device is advantageously arranged on the rear of the household appliance, with its flat design aligned in such a way that the depth of the appliance increases as little as possible.

[0026] These and other features emerge not only from the claims but also from the description and the drawings. The individual features may be implemented individually or in combination in an embodiment of the invention and in other fields, and may represent advantageous and individually protectable embodiments for which protection is claimed here. The division of the application into individual sections and subheadings does not limit the generality of the statements made therein. Brief description of the drawings

[0027] Embodiments of the invention are illustrated schematically in the drawings and explained in more detail below. The drawings show: Fig. 1 a schematic rear view of a steam oven according to the invention as a household appliance, Fig. 2 a steam generator according to the invention in a first embodiment in front view, Fig. 3 the steam generator from Fig. 2 in side view, Fig. 4 a steam generator according to the invention in a second embodiment in front view, Fig. 5 the steam generator from Fig. 4 in side view, and Fig. 6 the steam generator from Fig. 4 top view. Detailed description of the implementation examples

[0028] In the Fig. 11 shows a steam oven 11 according to the invention as a household appliance in a very simplified rear view, as is known per se from the prior art. It has a housing 12, inside which an oven muffle (not shown here but known from the prior art) is arranged as the treatment chamber mentioned above. A steam generator 15 according to the invention is arranged on a rear side 13 of the steam oven 11. It has two hoses known per se, one for the water supply and the other for the steam removal. This will be explained in more detail below. The steam generator 15 is arranged on the outside of the housing 12 so that it is insulated from the oven muffle, for example by thermal insulation provided in the housing 12. Furthermore, assembly, repair, and maintenance are thus easier.

[0029] In the Fig. 2The steam generator 15 according to the invention is shown in a first embodiment enlarged and in front view. It has, as can also be seen from the side view of the Fig. 3 As can be seen, it has a block-like or cuboid-like outer shape. A housing 16 of the steam generator 15 consists of a single part, although it can advantageously be manufactured in two parts or two shells and then assembled accordingly. The width of the housing 16 is approximately 25% greater than the height. The thickness according to Fig. 3 is just under 15% of the width. Thus, the housing 16 is relatively flat when positioned vertically.

[0030] A water storage chamber 18 is provided on the left side of the housing 16. By means of a water inlet 20 arranged at the top, water W can be admitted into the water storage chamber 18 through an aforementioned hose, advantageously by means of a pump and / or dosing device. This water W is then present in the water storage chamber 18 at a certain level P. This can, if necessary, be monitored and maintained at a certain level by sensors such as those known from the prior art, for example according to EP 1870641 A2. An optional drain outlet 22 is provided at the bottom of the water storage chamber 18. Leftover water that is no longer needed can be drained off here, thus avoiding hygiene problems. Likewise, cleaning fluid, for example for descaling, which should not evaporate, can be drained off here.

[0031] A water outlet 21 from the water storage chamber 18 is formed by a vertical partition 25 that does not extend to the bottom of the water storage chamber 18 or the housing 16, but rather ends, for example, 2 cm to 5 cm above it. To the right of the partition 25, a heating chamber 28 for the water W, as described above, is formed, in which the same level P for water W is established. The water outlet 21 thus simultaneously forms the heating chamber inlet 30 as a simple opening.

[0032] A steam outlet 31 branches off from the top of the heating chamber 28, connecting to the hose described above. A drain outlet or similar from the heating chamber 28 is not necessary; the drain outlet 22 of the water storage chamber 18 serves this purpose. A bottom of the housing 16 can also be designed at an angle toward the drain outlet 22 so that as much water as possible can drain away easily.

[0033] An opening 34 is provided on the flat side 33 of the housing 16, shown in dashed lines. This opening 34 is closed by a flat heating device 35, which is advantageously designed as the thick-film heating device described above. For this purpose, it can have a metallic heating carrier to which a thick-film heating element is applied in a known manner. This is sufficiently known from the prior art. A seal, for example made of silicone, can be provided between the flat side 33 of the housing and the heating device 35 in order to securely seal the opening 34. This makes it possible to remove the heating device 35 and replace it if necessary. Alternatively, the heating device 35 can be glued to the flat side 33 of the housing and thus also close or seal the opening 34. Electrical connections or the like for the heating device 35 are not shown. A cover or the like should also be provided.be arranged above it, for example also made of plastic, in order to protect the heating device 35 against damage and to electrically separate or insulate it.

[0034] The partition wall 25 can be arranged as a separate part in the housing 16, for example, glued in place, to divide it into the water storage chamber 18 on the one hand and the heating chamber 28 on the other. Alternatively, if the housing 16 is made from two half-shells that are joined together, it can be formed either entirely or partially or half-way onto one of these half-shells. Joining them together then forms the finished partition wall 25.

[0035] Furthermore, it can be seen from the illustration that the heating device 35 only just reaches above the intended level P. The water W can reach the heating device 35 directly through the opening 34 and thus be heated as directly and effectively as possible. Here, the heating device 35 covers approximately 60% to 70% of the outer side of the flat housing side 33 at the heating chamber 28. Mirrored, a further heating device for the heating chamber 28 could also be provided on the opposite flat housing side. However, this would require further thermal and / or electrical insulation of the steam generator 15 from the rear side 13 of the housing 12 of the steam oven 11.

[0036] Furthermore, the uppermost 15% to 20% of the heating device 35 can also heat the interior of the heating chamber 28 above the level P, thus heating the steam present there even more intensely. According to a further option, steel wool or the like can be provided in the heating chamber 28 to reduce calcification and to reduce blistering or boiling turbulence.

[0037] In addition to the aforementioned sensors for detecting the level P and for adjusting it, further sensors, particularly temperature sensors, can be provided for controlling the heating device 35 or the amount of steam generated. These are known per se from the prior art and can be advantageously arranged at a location on the steam generator 15 or its housing 16.

[0038] In the Fig. 4 to 6a second embodiment of a steam generator 115 according to the invention is shown, which can be mounted in the same way on the steam oven 11 according to Fig. 1 could be arranged. The steam generator 115 also has a housing 116 with identical external dimensions as before. A water storage chamber 118 provided on the left has a water inlet 120 at the top and a drain outlet 122 at the bottom left. The water storage chamber 118 is bounded to the right by a partition 125. A water outlet 121 is provided at the bottom right of the partition 125.

[0039] Unlike the first embodiment, a steam chamber 137 is provided to the right of the partition wall 125, into which water flows through the water outlet 121. The steam chamber 137 is separated from the heating chamber 128 to the right by an intermediate wall 138. Between the steam chamber 137 and the heating chamber 128, a lower passage 139 is formed at the lower end of the intermediate wall 138 and an upper passage at the upper end of the intermediate wall 138. Water W flows through the lower passage 139. Steam will flow through the upper passage 140, specifically from the heating chamber 128 to the steam outlet 131. The design of the intermediate wall 138 can be similar to that previously described for the partition wall 125. The advantage of the intermediate wall 138 here is that the intermediate wall 138, which extends far upwards and has a relatively small upper passage 140, prevents any splashing water droplets or the like. with escaping steam to the steam outlet 131.These would be very disruptive inside the steam oven 11. Thus, the partition wall 138 can serve as a kind of droplet separator.

[0040] From the Fig. 4 It can also be seen that the heating device 135 is narrower here than that of the Fig. 2 , in particular, approximately 30% narrower. This can be compensated for by a higher power density. Thus, although the steam chamber 137 also contains water, it is not directly heated. The steam outlet 131 is located directly at its top.

[0041] From the top view of the steam generator 115 according to the Fig. 6It can be seen that the partition wall 125 and the intermediate wall 138 are continuous from the front flat side 133 of the housing to the rear. Furthermore, the block-like or cuboid-like outer shape of the housing 116 is also clearly visible. The arrangement of the flat water storage chamber next to the equally flat steam chamber and heating chamber can also be seen, which, with the exception of the steam chamber, also applies to the first embodiment of the steam generator 15. It is therefore relatively flat and can be arranged on a household appliance in a space-saving manner. Due to the relatively large surface area, a large heating device can be attached, which evaporates water quickly and efficiently.

Claims

1. Steam generating device for a household appliance (11), comprising: - a water storage chamber (118) having a water inlet (120) and a water outlet (121), - a heating chamber (128) for water (W) from the water storage chamber (118), which has a heating chamber inlet connected to the water outlet (121) and a steam outlet (131), - a heating device (135) on the heating chamber (128) for heating and vaporizing water (W) therein, wherein - the water storage chamber (118) is arranged laterally adjacent to the heating chamber (128), - the device is wider in an extension direction from the heating chamber (128) to the water storage chamber (118) than it is high in a height direction perpendicular thereto and is at least 5 times wider than in a thickness direction perpendicular thereto - an intermediate wall (138) is arranged in the heating chamber (128), which divides the heating chamber (128) into two areas, wherein the areas have at least two connecting channels (139) for fluid-conducting connection to each other, - the areas are a heating area and a steam area, - the heating device (135) is arranged in the heating area, - the steam outlet (131) extends from the steam area, characterized in that the steam area is arranged between the water storage chamber (118) and the heating chamber (128).

2. Device according to claim 1, characterized in that the water storage chamber (118) and the heating chamber (128) form a single unit with a single common housing (116), preferably made by plastic injection molding.

3. Device according to claim 1 or 2, characterized in that the structural unit has a cuboid shape, wherein preferably a width in the horizontal direction is greater than a height in the vertical direction and wherein, in particular, a thickness in the horizontal direction is between 5% and 20% of the width in the horizontal direction.

4. Device according to one of the preceding claims, characterized in that the water storage chamber (118) and the heating chamber (128) are separated by a housing partition (125) and the water outlet (121) corresponds to the heating chamber inlet and is formed by an opening (121) and / or interruption in the housing partition (125).

5. Device according to one of the preceding claims, characterized in that the heating device (135) is arranged on the outside of the heating chamber (128), wherein the heating device (135) is preferably designed to be flat and in particular covers at least 20% of the outer surface of the heating chamber (128).

6. Device according to claim 5, characterized in that the heating chamber (128) has two flat or flat opposite outer sides, wherein the heating device (135) is preferably arranged only on one of the outer sides and the other flat outer side is without a heating device (135).

7. Device according to one of the preceding claims, characterized in that the heating device (135) is a thick-film heating device, in which, in particular, a thick-film heating element is applied directly to a metallic heating carrier, wherein the heating device (135) with the heating carrier is arranged on an outer side of the heating chamber (128).

8. Device according to one of the preceding claims, characterized in that the water inlet (120) and / or the steam outlet (131) protrude upward, preferably away from the housing (116) according to claim 2, in particular each from an uppermost region of the water storage chamber (118) and the heating chamber (128).

9. Device according to one of the preceding claims, characterized in that a drain outlet (122) extends from the water storage chamber (118), in particular from a lower region or the lowest point of the water storage chamber (118).

10. Household appliance with a device for generating steam according to one of the preceding claims, wherein the household appliance (11) has a housing (12) and a treatment chamber arranged in the housing (12), wherein the device (115) for generating steam is arranged outside the treatment chamber.

11. Household appliance according to claim 10, characterized in that the household appliance (11) is an oven or a steam cooker.

12. Household appliance according to claim 10 or 11, characterized in that the device (115) for generating steam is arranged on the outside of the housing (12), preferably on a rear side (13) of the household appliance (11).

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