EP1673002B1 - Dishwasher comprising a drying apparatus - Google Patents

Abstract

The aim of the invention is to create a drying apparatus which allows the wet washed dishes located in the washing container to be dried quickly from an economic and hygienic point of view. Said aim is achieved by a dishwasher in which a drying apparatus for drying washed dishes is disposed inside the dishwasher and circulates exclusively the air located in a washing container (1) of the dishwasher. Said drying apparatus is provided with a suction port (2) for introducing the air from the washing container into the drying apparatus, a blow-out port (3) for discharging the air from the drying apparatus into the washing container, a conveying section (5) between the suction port and the blow-out port, and a fan (4) for conveying the air from the suction port to the blow-out port via the conveying section. The conveying section encompasses a condensing section (11) in which at least one wall of the conveying section is embodied as a condensing surface (8) whereupon the humidity contained in the air condenses.

Description

The invention relates to a dishwasher with a drying device for drying items to be washed.

In a dishwasher, one or more rinsing operations are usually carried out in the course of the rinsing operation in order to clean the items to be washed in the dishwasher. To increase the cleaning effect while the rinsing liquid is heated before or during a rinsing process by means of electric heaters. After the last rinsing process usually takes place a rinse phase, followed by a drying process followed to dry the items to be washed. For drying items to be washed in a dishwasher, different methods are known.

The items to be washed can be dried, for example, by means of self-heat drying with the aid of a heat exchanger, by heating the rinsing liquid for rinsing and thus drying the rinsing product, which has been rinsed hot, by itself in such a way as to generate self-heat during the drying process. In order to achieve this self-heat drying, the final-rinse liquid is heated to a certain temperature in the heat exchanger and applied to the items to be washed via the spraying devices present in the dishwasher. Due to the relatively high temperature of the final rinse liquid of usually from 65 ° C to 70 ° C is achieved that a sufficiently large amount of heat is transferred to the items to be washed, so that the water adhering to the items evaporated by the heat stored in the items to be washed

In another known method of heating or drying the dishes in dishwashers, a separate heat source, e.g. a hot air blower, used to heat the humid air mixture during the drying process, so that the air in the rinse tank can absorb a larger amount of water.

A disadvantage of the above-described methods for heating or drying of items to be washed in dishwashers according to the prior art is that the heating of the washing liquid is associated with a high energy requirement and regenerates the required heat energy for each heating phase by means of electrical heating elements must become. Likewise, the known methods have the disadvantage that the heating of the final rinse liquid and the drying processes themselves are associated with a high energy requirement and the required heat energy is lost after the drying process.

In order to direct the humid air mixture in the rinsing tank out of the rinsing tank as quickly as possible in order to accelerate the drying phase, it is furthermore known in the state of the art to convey the moist air mixture from the rinsing tank into the outside atmosphere by means of suitable blowers. The disadvantage of these drying devices has been found that the humid air mixture lead to mold in the rooms or can be perceived by the user as disturbing.

In a further drying device of the prior art outside air is passed into the washing and thus improves the drying performance. A disadvantage has been found in this drying device that the introduction of outside air from a hygienic point of view is not suitable and the supply of outside air is always accompanied by a partial escape of air in the washing container.

For example, the dishwasher has the DD 128 108 A a recirculating air duct, through which steam is sucked out of the washing compartment by means of a blower and is returned via a condenser as relatively dry air into the washing compartment of the dishwasher. In this case, the circulating air channel is formed as a whole as a condensation channel and distributed over the length of the condensation channel distributed at least two slots arranged transversely to the flow direction.

The dishwasher of the FR 2 491 319 A1 has a condensation device, which is designed as upwardly directed, open-topped shaft with labyrinthine arranged therein transverse walls. The condensation device is arranged between the left container side wall and the associated machine panel.

In the drying device of the dishwasher of FR 2 491 322 is for guiding air, a conduit system provided, the downwardly extending portion formed as a condensation shaft with a collecting bag for condensate. The condensation shaft is heat-insulated from the adjacent right-hand side wall of the container profiled. The conduit system is expediently formed from a one-piece plastic part, for example as a blow-molded part. The line system extends on the one hand with its the container side inlet opening having a portion and its outlet opening for air containing another section between a side wall of the washing and the small machine panel to this distance and on the other hand its a fan and a heater having central portion of the conduit system in the free space below the tank bottom.

In the dishwasher of DE 100 24 892 A1 its loading door is double-walled. The loading door in this case comprises an inner door panel and an outer door panel, which are arranged at a distance from each other to form a gap formed as an air gap. In order to dampen drum noise, which are caused by impinging on the inner door panel spray jets, an insulating fleece is attached to the side facing away from the washing compartment of the inner door panel. To condense moisture flows through humid air from the interior of the washing compartment, the space between the outer door panel and the inner door panel. Since now the outer door panel for the passing through the air gap moist air is the relatively coldest component condenses there as it flows through the moist air from part of the moisture, runs down the outer door panel down and is in the lower edge of the outer door panel of a groove-shaped and parallel held to the bottom edge of the outer door panel aligned strips of material. The strip of material which receives the condensate comprises a capillary material, e.g. B. blotting paper. Between the drying phases of two successive rinses, the condensate passes through the capillary structure of the gutter material on the outwardly directed surface and evaporates there.

The object of the present invention is therefore to provide a drying device with which it is possible, from an economic and hygienic point of view, to quickly dry the moist items to be washed located in the washing container.

This object is achieved by the dishwasher according to the invention with the features of claim 1. Advantageous developments of the present invention are characterized in the subclaims 2 to 10. In the dishwasher according to the invention, a drying device is provided for drying items to be washed, wherein the drying device is arranged inside the dishwasher and only circulates the air in a washing container of the dishwasher. The drying device comprises a suction opening for introducing the air from the washing container into the drying device, an outlet opening for discharging the air from the drying device into the washing compartment, a transport path between the suction opening and the outlet opening and a fan for Carrying the air from the suction port through the transport path to the exhaust port, wherein the transport path has a condensation section, in which at least one wall of the transport path is formed as a condensation surface, at which the moisture contained in the air is reflected.

The principle on which the present invention is based, therefore, is to reduce the humidity present in the washing container during the drying process by removing the moisture from the air in the washing container as it flows through the drying apparatus. A dishwasher with the system according to the invention for drying items to be washed thus has the advantage that both the drying time and the energy required for drying the items to be washed are reduced.

The dishwashers according to the invention also provide the advantage that no moisture-laden air is released into the ambient atmosphere, whereby harmful influences on the furniture, such as e.g. Mold formation is avoided. Furthermore, the items to be washed do not come into contact with the outside air during drying, so that a high standard of hygiene can be ensured. In addition to the advantages of saving energy, the temperature effects of the final rinse liquid further reduce the effects of stress on the items to be washed, so that the danger of hairline cracks is reduced, for example, in the case of ceramic dishes or earthenware containers.

The above principle is based on the fact that the condensation surface has a lower temperature than the air in the washing container. In a preferred embodiment of the dishwasher according to the invention, the condensation surface of the drying device is in heat-conducting contact with an outer wall of the dishwasher. For this purpose, the wall of the transport path is formed as a condensation surface, which bears against the outer wall of the dishwasher. Since the outer walls of the dishwasher generally consist of a metal housing, the housing of the dishwasher is particularly well suited as a cooling surface. In this way, a good heat dissipation from the condensation surface is ensured to an outer wall of the dishwasher.

In the manufacture of a dishwasher, the housing is usually mounted in one of the last steps when the rinse tank is already connected to all associated components. The drying device is therefore already arranged on the washing container when the housing is mounted around the washing container. In order to ensure a direct connection between the condensation surface and the outer wall of the dishwasher without any intermediate air gap and thus good heat conduction to the housing of the dishwasher, the condensation surface is made according to the invention of a flexible material. As soon as the air from the washing container is conveyed by the blower through the transport path of the drying device, the flexible wall of the conveying line designed as a condensation surface can expand outwards and come into contact with the outer wall of the dishwasher. For this purpose, the condensation surface is preferably formed in the form of a film of plastic or metal, in particular aluminum. While a film made of plastic has the advantage of being able to flexibly absorb point loads due to its extensibility, a film of metal is characterized by a high thermal conductivity.

In a further embodiment of the present invention, the drying device is substantially thermally insulated from the rinsing container, so that the transport path and in particular the condensation section remains as cool as possible in relation to the interior of the rinsing container. This makes it possible to achieve the greatest possible temperature difference between the air introduced from the rinsing container into the drying device and the condensation section and thus the most efficient possible condensation effect.

Expediently, the condensation section has at least one swirl vane protruding into the interior of the transport section, which causes a turbulence of the air flowing through the condensation section. As a result, the residence time of the air in the condensation section is increased and the contact of the air to the condensation surface intensified, which supports the condensation effect described above.

The condensation effect is further increased if the suction opening of the drying device is arranged in the upper region of the washing container and the discharge opening of the drying device in the lower region of the washing container. Since the warm, humid air is in the upper area of the washing container, the arrangement the suction opening in the upper region of the washing container ensures that the air is conveyed from the region of the washing container into the drying device at which the highest humidity is present. Due to the arrangement of the exhaust opening in the lower region of the washing container, a circulation movement of the air through the washing container and the drying device is promoted.

Expediently, the drying device also has a discharge, through which the water precipitated in the condensation section is discharged. In this case, the precipitated in the drying device water can be passed, for example, in the pump pot of the dishwasher or conveyed through the drain pump from the dishwasher.

In the transport path of the drying device, a heating device is preferably provided immediately in front of the discharge opening, which heats the air passing by it before it enters the washing container. The heating device is designed for example as a heating coil, which is arranged on the inner wall of the transport path. This allows the air to be heated prior to re-entry into the purge vessel to provide the air with a greater capacity to absorb moisture, which accelerates the drying process. After the air has absorbed the moisture from the items to be washed, it is conveyed via the blower through the suction port back into the drying device. When flowing through the condensation section of the air is deprived of moisture, when passing the heater, the air is reheated and thus the circuit is closed.

In a further embodiment of the present invention, the fan is arranged with respect to the flow direction of the air behind the condensation section. Since the air in the condensation section is at least partially deprived of moisture, the arrangement of the fan with respect to the flow direction of the air behind the condensation section has the advantage that the fan is charged with the lowest possible humidity. Conveniently, both the fan and the heater with the program control of the dishwasher is connected so that according to the Spülprogrammstatus the fan and according to the heater is controlled.

The circulation of the air and the removal of the humidity in the dishwasher according to the invention both a homogeneous heat distribution within the drying air and a uniform flow through the Spülbehälters achieved, which has a higher efficiency and thus better energy values for the operation of the dishwasher invention.

Advantageously, the transport path is arranged in a side wall or in the door of the dishwasher. It is also possible to arrange the transport path in the rear region of the washing, but in particular offers the side wall and the door, because on the one hand in these areas outbreaks already exist, such as the expansion shaft for compensating pressure peaks in the washing. On the other hand, the side walls and the door of a dishwasher generally have an exposed position and therefore provide efficient heat dissipation.

Figur 1

eine Schnittdarstellung durch einen erfindungsgemäßem Geschirrspüler mit einer in der Seitenwand untergebrachten Trocknungseinrichtung;

Figur 2

eine Schnittdarstellung durch die in Figur 1 dargestellte Trocknungseinrichtung.

The present invention will be explained in more detail with reference to a preferred embodiment with reference to the accompanying drawings. Show it:

FIG. 1

a sectional view through a dishwasher according to the invention with a accommodated in the side wall drying device;

FIG. 2

a sectional view through the in FIG. 1 illustrated drying device.

The dishwasher according to the invention FIG. 1 has a washing container 1 with a drying device in the side wall, a suction opening 2 for introducing air from the washing compartment 1 into the drying device, a blow-out opening 3 for discharging the air from the drying device into the washing compartment 1 and a transport path 11 between the suction opening 2 and the discharge opening 3 and a fan 4 for conveying the air from the suction port 2 through the transport path 5 to the exhaust port 3. The transport path 5 comprises a condensation section 11, in which the humidity precipitates, since the condensation section 11 has a lower temperature than the moist, warm air from the washing container 1. The condensation section 11 is additionally equipped with a number of swirl vanes 6, which protrude into the interior of the transport route and thereby cause turbulence of the air flowing through the condensation section 11 air, which supports the condensation effect.

The suction opening 2 is located in the upper region of the washing container 1 and the discharge opening 3 in the lower region of the washing container 1. As a result, the warm moist air from the upper region of the washing container 1, in which the highest humidity is present, transported into the drying device. Due to the arrangement of the discharge opening 3 in the lower region of the washing container 1, a circulation movement of the air through the washing container and the drying device is established.

During the drying phase, the blower 2 connected to a control unit (not shown) is activated and sucks in moist air through the suction opening 2 from the washing container 1. In further transport of the moist air through the transport path 5, the moist air passes through the condensation section 11, in which the humidity is at least partially reflected. Subsequently, the air is heated at a heater 7 and thus is able to absorb a larger amount of moisture. By now located at the end of the transport section 5 outlet 3, the now heated and dehumidified air is introduced back into the washing 1 and can be there to distribute the wet items to be washed. By thus constructed circulation flow a rapid and homogeneous drying behavior within the washing compartment 1 is achieved.

FIG. 2 shows a sectional view taken along by the reference numeral AA in FIG. 1 defined level by the in FIG. 1 illustrated drying device. It can be seen that the transport channel 5 in the region of the condensation section 11 has a condensation surface 8, which bears directly against an outer wall 9 of the dishwasher. On the opposite side of the transport channel 5 is separated by a heat-insulating layer 10 from the washing compartment 1. The transport path 5 is at least partially designed as a condensation section 11, wherein the (not shown) on the outer wall 9 of the dishwasher wall of the transport path 5 serves as a condensation surface 8.

While the transport channel 5 is thermally insulated from the washing container 1, thus the condensation surface 8 of the drying device is in heat-conducting contact with the outer wall 9 of the dishwasher and is maintained by this at a temperature level which corresponds approximately to the room temperature. Since the outer walls 9 of the dishwasher are generally made of metal, they are particularly suitable as cooling surfaces. In this way, good heat dissipation from the condensation surface 8 to the outer wall 9 of the dishwasher and further to the environment is ensured. Consequently, the condensation surface 8 during the drying operation to a lower temperature than the originating from the washing tank 1 moist warm air, whereby the condensation effect arises.

To ensure that between the condensation surface 8 and the outer wall 9 of the dishwasher always a good system and thus a good heat conduction to the housing of the dishwasher is present, the condensation surface 8 is made of a flexible material. As soon as the air from the washing container 1 is conveyed by the blower 4 through the transport path 5 of the drying device, the condensation surface 8 of the condensation section 11, which is designed as a flexible wall, can expand outwards and come into contact with the outer wall 9 of the dishwasher. The condensation surface 8 is formed for example as a film which is made of plastic or metal, in particular aluminum.

List of reference numbers

1

rinse tank

2

suction

3

exhaust vent

4

fan

5

Transport route between intake and exhaust

6

swirl

7

heater

8th

Condensation surface or condensation film

9

Exterior wall of the dishwasher

10

Thermal insulation layer between drying device and washing container

11

condensation section

A-A

Cutting plane of Fig. 2

Claims (10)

1. Dishwasher with a drying device for drying articles to be washed, wherein the drying device is arranged within the dishwasher and exclusively circulates the air present in a rinsing container (1) of the dishwasher, comprising a suction opening (2) for introducing air from the rinsing container (1) into the drying device, an exhaust opening (3) for discharging the air from the drying device into the rinsing container (1), a transport path (5) between the suction opening (2) and the exhaust opening (3) and a fan (4) for conveying the air from the suction opening (2) through the transport path (5) to the exhaust opening (3), wherein the transport path (5) has a condensation path (11) in which at least one wall of the transport path (5) is formed as a condensation surface (8) at which the moisture present in the air precipitates, characterised in that the condensation surface (8) is formed from flexible material, preferably in the form of a foil of plastic material or metal, particularly of aluminium.
2. Dishwasher according to claim 1, wherein the condensation surface (8) is in thermally conductive contact with an outer wall (9) of the dishwasher.
3. Dishwasher according to one of the preceding claims, wherein the condensation path (11) is substantially thermally insulated relative to the rinsing container (1).
4. Dishwasher according to any one of the preceding claims, wherein the condensation path (11) has at least one turbulence vane (6) projecting into the interior of the transport path (5).
5. Dishwasher according to any one of the preceding claims, wherein the drying device has a drain by which the water precipitated in the condensation path (11) is drained away.
6. Dishwasher according to any one of the preceding claims, wherein a heating device (7) is provided preferably directly in front of the exhaust opening (3), which heats the air - which is going past - before entry into the rinsing container (1).
7. Dishwasher according to any one of the preceding claims, wherein the fan (4) is arranged behind the condensation path (11) with respect to the flow direction of the air.
8. Dishwasher according to one of claims 6 and 7, wherein not only the fan (4), but also the heating device (7) are activated by a program control of the dishwasher.
9. Dishwasher according to any one of the preceding claims, wherein the suction opening (2) of the drying device is arranged in the upper region of the rinsing container (1) and the exhaust opening (3) of the drying device is arranged in the lower region of the rinsing container (1).
10. Dishwasher according to any one of the preceding claims, wherein the transport path (5) is arranged in a side wall and/or in the door of the dishwasher.

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