EP2574267B1 - Household appliance, in particular dishwasher - Google Patents

Description

The invention relates to a household appliance, in particular in the embodiment as a dishwasher, with a washing container and a drying device for drying the dishes located in the washing, wherein the drying device has a sorption with a housing for receiving reversibly dehydratable sorbent, and with a drying device with the Flushing fluidly connecting air duct.

A household appliance of the type mentioned, that is generic type is from the DE 10 2008 038 504 A1 and from the DE 10 2008 043 933 A1 known.

The so-called "Sorptionstrocknung" is known from the prior art per se. Thereafter, for the purpose of dish drying the washing compartment provided by the washing container, the moist air located there after the last rinse is removed and fed to a drying device. In the drying device, a drying of the air, that is, a dehumidification of the same takes place and the dried air then passes from the drying device back into the washing compartment. By means of a blower, the air is circulated and the air exchange thus generated between the washing container and the drying device is maintained until a desired drying of the air and thus also of the items to be washed in the washing compartment is achieved.

The drying device has a sorption unit with a housing which provides a reversibly dehydratable sorbent, the humid air taken from the rinsing space is passed through the sorption unit, as a result of which there is contact between the moist air and the sorbent provided by the sorption unit. In this case, moisture is removed from the moist air by the reversibly dehydratable sorbent by adsorption, as a result of which it comes to air drying.

For the purpose of regeneration, that is, desorption of the sorbent, it is heated. As a result, the previously absorbed by the sorbent water exits as hot water vapor and is thereby removed from the drying device. Typically, in a regeneration process, the released hot steam for the purpose of heat recovery is supplied to the washing container, where then a warming of the rinsing liquor and / or the washware located in the washing can take place.

Although drying devices of the type described above have proven themselves in everyday practical use, there is a need for improvement, in particular with regard to a still further improved efficiency. It is therefore an object of the invention to further improve a household appliance of the type mentioned in terms of its drying device, in particular from the viewpoint of energy conservation.

To solve this problem, a household appliance with the features of claim 1 is proposed with the invention.

The peculiarity of the embodiment according to the invention is the positioning of the sorption at least partially within the washing compartment provided by the washing compartment. This embodiment has the advantage that the heat of dissipation emitted via the surface of the housing of the sorption unit can be released at least in part to the washing compartment and thus in particular to the washing liquor located there. This advantage has a positive effect, in particular in the case of regeneration or desorption, since the otherwise unused desorption energy can be supplied to the rinsing process. The power loss is minimized thanks to the design according to the invention, resulting in the result in an improved in the energy yield device.

The desorption of the sorbent typically takes place at the beginning of a rinsing process, so that after completion of the last rinsing step - the rinse - the sorbent for a subsequent rinsing subsequent drying step in the intended manner. It is therefore proposed to carry out a desorption of the sorbent during the rinsing process step of the cleaning. The heat loss delivered via the housing of the sorption unit can in this case be delivered to the rinsing liquor to be heated up anyway for the rinsing process step of the cleaning. Along with this, an energy saving is achieved with regard to the entire work process, since it is no longer necessary to supply so much energy from outside to heat up the rinsing liquor.

The sorption unit is preferably arranged within the level assumed by the rinsing liquor in the rinsing container. In the intended use case, the sorption unit according to this embodiment is to a large extent, preferably completely surrounded by the rinsing liquor, that is over the entire free surface of the sorption can be transferred to the rinsing liquor in the desorption case released heat loss. The energy recovery can be maximized in this way.

The sorption unit is arranged according to the invention at least partially within the washing container. It is according to an alternative, the sorption completely formed within the washing container. The usable heat transfer area is maximized.

For the purpose of regeneration, that is, desorption of the sorbent, the sorbent is to be heated. For this purpose, known from the prior art sorption units have a heater. During the regeneration process, air is sucked from the purge bin and passed through the sorbent. This happens, for example, by means of a blower. In the flow direction before the sorbent, the heater is arranged. The sucked air passes through the heater and warms up. Then, the heated air is passed through the sorbent, as a result of which it comes to a heating of the sorbent with the result that stored therein water evaporates. The water vapor is entrained by the air conducted through the sorbent and transported from the sorbent to the rinse tank.

Upon completion of the regeneration process, the sorbent is still heated due to the previously performed heating. In devices known from the prior art, this heat energy contained in the sorbent is lost unused. The embodiment according to the invention makes this heat energy usable for a subsequent rinsing process by ensuring, on account of the embodiment of the sorption unit according to the invention, that the heat loss energy output via the housing of the sorption unit is delivered to the rinsing liquor in the rinsing container.

According to a further feature of the invention, it is provided that the sorption unit is arranged above the bottom of the washing container. According to this embodiment, a complete embodiment of the sorption unit takes place within the rinsing container. In this case, the sorption unit uses the volume space formed between the bottom of the washing container and a lower spray arm arranged in the washing container as installation space. It is preferably provided in this connection that the sorption unit is designed to be relatively flat, so that an impairment of the spray arm is excluded in its movement. Depending on the design of the washing container or of the household appliance, the sorption unit has a heightwise direction Extension of less than 20 mm, preferably less than 15 mm, more preferably from 3 mm to 10 mm, most preferably from about 5 mm.

It is furthermore preferred according to a further feature of the invention that the sorption unit has a planar design and largely covers the bottom of the washing container. It is created as a maximum heat transfer surface between sorption and Spülflotte befindlicher in the washing.

According to an alternative embodiment of the invention, the sorption unit is arranged only partially within the washing container. In this case, the bottom of the washing container has a recess into which the sorption unit is inserted projecting from below the bottom into the washing compartment. For the purpose of sealing corresponding sealing means are used, which accomplish a sealed arrangement of the sorption in the recess of the soil, so that a tight closure of the washing is ensured.

According to a further feature of the invention, the sorption unit cooperates with a liquor heater arranged in the flushing chamber pot, also called collecting pot. In this connection, it is preferable that the sorption unit is one having a low desorption temperature, for example, silica gel.

Typically, the heating of the sorbent in the regeneration case by means of air, which is passed before passing through the sorbent to a heater. The embodiment of the invention allows in this regard an alternative. Thus, the heating of the sorbent can also be carried out with the liquor heating present anyway in the washing container, which heats the heating to heat the washing liquor. A heater for Sorptionsmittelerwärmung can be completely eliminated according to this alternative embodiment.

For the purpose of heating the sorbent, the heating of a rinsing liquor in the rinsing tank is initially carried out by means of the liquor heating. The warmed up rinsing liquor releases heat via the contact surface of the housing of the sorption unit to the sorption unit and thus also to the sorption agent provided by the sorption unit. As a result, there is a heating of the sorbent. In known manner, air is then passed through the sorbent to discharge the moisture, wherein, in contrast to vorerläuterten procedure, a prior heating of the air for the purpose of heating the sorbent is not required. Since the fleet heating is designed for a fleet temperature of a maximum of about 70 ° With respect to the sorption unit, preferably a sorption agent is used which has a low desorption temperature. It is thus ensured that the amount of heat supplied by the fleet heating is sufficient to perform a proper desorption of the sorbent can. As a desorbent, for example, silica gel can be used.

Fig. 1

In einer schematischen teilgeschnittenen Seitenansicht ein Haushaltsgerät nach der Erfindung gemäß einer ersten Ausführungsform;

Fig. 2

in schematischer Draufsicht von oben den Bodenbereich des Spülbehälters des Haushaltsgeräts nach Fig. 1:

Fig. 3

in einer schematischen teilgeschnittenen Seitenansicht ein Haushaltsgerät nach der Erfindung gemäß einer zweiten Ausführungsform und

Fig. 4

in einer schematischen teilgeschnittenen Seitenansicht ein Haushaltsgerät nach dem Stand der Technik.

Further features and advantages of the invention will become apparent from the following description with reference to FIGS. Show

Fig. 1

In a schematic partially sectioned side view of a household appliance according to the invention according to a first embodiment;

Fig. 2

in a schematic plan view from above the bottom portion of the washing container of the household appliance Fig. 1 :

Fig. 3

in a schematic partially sectioned side view of a household appliance according to the invention according to a second embodiment and

Fig. 4

in a schematic partially sectioned side view of a household appliance according to the prior art.

The FIGS. 1 to 3 let recognize a designed in accordance with the invention household appliance in the form of a dishwasher 1. There are shown two different embodiments, wherein the FIGS. 1 and 2 a first embodiment and Fig. 3 relate to a second embodiment. Fig. 4 shows a dishwasher 1 according to the prior art according to the DE 10 2008 038 504 A1 ,

Fig. 4 shows a dishwasher 1 according to the prior art according to the DE 10 2008 038 504 A1 , It has a rinsing 2, which serves to receive items to be cleaned, which is not shown in detail in the drawings.

Within the rinse tank 2 crockery baskets 3 are arranged for the purpose of Spülgutaufnahme. There are also provided in a conventional manner spraying arms 4, which serve in the intended use of the loading of the items to be cleaned with rinse 7.

The dishwasher 1 further has a drying device 20. This has a sorption unit 10 with a housing 19 which is the receptacle of a Sorbent 11 is used. Within the housing 19, a heater 12 is further arranged, which is connected upstream of the sorbent 11 in the air flow direction.

The drying device 20 is connected to an air duct 21. This is connected via an air inlet 14 in fluid communication with the washing container 2. On the outlet side, an outlet 15 is provided, which also connects the drying device 20 in terms of flow with the washing container 2. In order to avoid penetration of rinsing liquor into the sorption unit 10, the outlet 15 is provided on the outlet side with a cover 16.

In the air duct 21, a blower 13 is integrated. In the intended use case is sucked by this humid process air 17 from the washing container 2 and fed to the sorption 10 of the drying device 20. Here, drying of the process air then takes place so that heated and dry process air 18 can be dispensed into the washing compartment 2 via the outlet 15.

According to the prior art, drying of the process air takes place in that the wet process air 17 taken from the washing container 2 via the air duct 21 is fed to the sorption unit 10. Within the sorption unit 10 there is contact of the moist process air with the sorbent 11 provided by the housing 19 of the sorption unit 10. In the process, moisture is removed from the moist process air by adsorption due to the sorption agent, as a result of which air drying takes place.

For the purpose of regeneration of the sorbent 11 process liquid is also removed from the washing container 2. Before introducing the process air into the sorbent 11, the air passes through the heater 12 upstream of the sorbent 11, as a result of which air heating occurs. The warm air then flows through the sorbent 11, resulting in heating of the sorbent 11, which in turn results in expulsion of the moisture held by the sorbent 11 by evaporation. The air guided through the sorption unit 10 entrains the moisture evaporated from the sorbent 11 and transports it back into the washing compartment provided by the washing container 2.

As the representation after Fig. 4 can be clearly seen, the embodiment of the prior art provides to arrange the sorption unit 10 below the bottom 22 of the washing container 2.

The embodiment of the invention is in a first embodiment in Fig. 1 shown. As can be seen from this illustration, it is provided according to the invention not to arrange the sorption unit 10 in contrast to the prior art below the bottom 22 of the washing container 2, that is, outside the washing container 2. Rather, the arrangement of the sorption unit 10 is provided within the washing container 2, at least partially, such as Fig. 3 according to a second embodiment of the invention.

Preferably, the sorption unit 10 is disposed within the level occupied by the rinsing liquor 7, i. the sorption unit is in direct contact with the rinsing liquor.

The embodiment according to the invention affords the advantage that the desorption energy released, in particular, during a regeneration process does not remain unused, but can be recovered, since heat transfer from the free surface of the housing 19 of the sorption unit 10 to the rinsing liquor 7 surrounding the sorption unit 10 takes place.

The sorption unit 10 is formed in the region between the bottom 22 of the washing container 2 and the spray arm 4 which is arranged at the bottom in the vertical direction. The height extent of the sorption unit 10 may be, for example, 10 mm.

The washing container 2 has in known manner in the region of the bottom 22 via a collecting pot 5, which also provides a liquor heater 8 in a conventional manner. The collection pot 5 is covered by a sieve 6. In order to allow access to the sieve 6, the sorption unit 10 has a corresponding opening, as in Fig. 2 shown. In contrast to the prior art, the sorption unit 10 has no additional heating 12. The heating of the sorption agent 11 provided by the sorption unit 10 for the purpose of regeneration takes place by means of the liquor heater 8 provided in the collecting pot 5 anyway. The heat is present in the washing container 2 Rinse liquor 7 of the liquor heater 8 transmitted to the Sorptionseinheit 10.

In an alternative embodiment, it may of course also be provided to design the sorption unit 10 with a heater 12. This may be necessary in particular when a sorbent having a comparatively high desorption temperature is used, for example zeolite.

Fig. 3 shows an alternative embodiment of the invention. Thereafter, the sorption unit 10 is only partially disposed within the washing container 2, with the area of the sorption unit 10 containing the sorbent 11. The bottom 22 of the washing compartment 2 has for this purpose a corresponding opening or a corresponding recess. In order to avoid escape of rinsing liquor 7, the parting plane between the sorption unit 10 and the bottom 22 of the washing compartment 2 is closed by means of a seal. As a sorbent zeolite can be used according to this embodiment. This is because with only a partial embodiment of the sorption unit 10 within the washing container 2 sufficient space for the design of a heater 12 remains, so that sorbents with a higher desorption temperature can be used.

The embodiment of the invention provides over the prior art in particular the following advantages: The otherwise unused in the prior art heat loss during the desorption process is fully utilized in the embodiment of the invention and the rinse liquor or the rinsing 2 fed. The heating power of the desorption heater 12 can be minimized. Optionally, depending on the embodiment, the desorption heater 12 may even be completely dispensed with. In this case, heating of the sorbent 11 takes place alternatively via the rinsing liquor 7, that is to say by means of the liquor heater 8. The process efficiency, ie the ratio between the desorption energy, ie the energy which regenerates the sorbent and the energy supplied to the process during the desorption , is close to 100%, that is, the process efficiency is significantly higher in contrast to the prior art, because it is due to the strong heat loss performance only a process efficiency of about 50% achieved.

reference numeral

1

dishwasher

2

rinse tank

3

dish rack

4

spray arm

5

collecting pot

6

scree

7

rinsing

8th

fleet Heating

10

sorption

11

sorbents

12

heater

13

fan

14

inlet

15

outlet

16

cover

17

Process air, humid

18

Process air, heated and dry

19

casing

20

drying device

21

Lutführungskanal

22

ground

23

breakthrough

Claims (9)

1. Domestic appliance, more particularly a dishwasher (1), comprising a washing container (2) and a drying means (20) for drying washware located in the washing container (2), the drying means (20) comprising a sorption unit (10) having a housing (19) for receiving reversibly dehydratable sorbent (11), and comprising an air duct (21) placing the drying means (20) in fluid communication with the washing container (2), characterised in that all or at least part of the sorption unit (10), namely the region of the sorption unit (10) which contains the sorbent (11), is arranged inside the washing container (2).
2. Domestic appliance according to claim 1, characterised in that the sorption unit (10) is arranged above the base (22) of the washing container (2).
3. Domestic appliance according to claim 1, characterised in that the base (22) of the washing container (2) has a recess into which the sorption unit (10) is inserted from underneath the base (22) so that it protrudes into the washing container (2).
4. Domestic appliance according to any of the preceding claims, characterised in that the sorption unit (10) is arranged in the installation space between the base (22) of the washing container (2) and a lower spray arm (4) arranged in the washing container (2).
5. Domestic appliance according to any of the preceding claims, characterised in that the sorption unit (10) has an extension in the vertical direction of less than 20 mm, preferably of less than 15 mm, more preferably of from 10 to 3 mm, most preferably of approximately 5 mm.
6. Domestic appliance according to any of the preceding claims, characterised in that the sorption unit (10) is configured in a planar manner and extensively covers the base (22) of the washing container (2).
7. Domestic appliance according to any of the preceding claims, characterised in that the sorption unit has an aperture (23) in the region of a washing chamber vessel (5).
8. Domestic appliance according to any of the preceding claims, characterised in that a solution heating device (8) is arranged in the washing chamber vessel (5) and cooperates with the sorption unit (10).
9. Domestic appliance according to any of the preceding claims, characterised in that the sorption unit is a unit of this type having a low desorption temperature, preferably silica gel.

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