EP1830688A1

EP1830688A1 - Water-conducting household appliance and method for the operation thereof

Info

Publication number: EP1830688A1
Application number: EP05797125A
Authority: EP
Inventors: Egbert Classen; Helmut Jerg
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2004-12-23
Filing date: 2005-10-20
Publication date: 2007-09-12
Anticipated expiration: 2025-10-20
Also published as: US20080149138A1; RU2007121897A; US20130228197A1; CN200987658Y; WO2006069830A8; DE102004062242A1; US20110114122A1; KR20070089708A; BRPI0519206A2; JP2008525072A; EP1830688B1; RU2405404C2; WO2006069830A1; US8663393B2; US8574376B2; US7909941B2

Abstract

Disclosed is a water-conducting household appliance, especially a dishwasher (1), comprising at least one substantially closed water circuit (6) in which rinsing liquid (7) is circulated according to a program control unit, the rinsing liquid being conveyed through a filter element (14) while circulating in order to filter out dirt. Another water circuit (15) is provided through which the rinsing liquid is circulated according to the program control unit when the filter element (14) is covered with dirt in order to cause the filter element (14) to be cleaned.

Description

Water-conducting household appliance and method for operating the same

The invention relates to a water-conducting household appliance, in particular a dishwasher, with at least one substantially closed water circulation, in which rinsing liquid is circulated in accordance with a program control unit, wherein the rinsing liquid is conveyed during the circulation for filtering impurities through a filter element. The invention further relates to a method for operating a water-conducting household appliance.

When operating a dishwasher, depending on the degree of soiling of the items to be cleaned, larger and smaller impurities are removed from the items to be washed by the rinsing liquid. In order to prevent rinsing liquid already being circulated during a rinsing program section from being applied again to the items to be washed, known dishwashers have arranged more or less complex filter arrangements in the area of the rinsing pan or the sump. A filter arrangement mounted in the sump of the dishwasher often consists of a coarse sieve which filters out large-diameter contaminants from the rinsing liquid, a fine sieve whose mesh diameter is in the range from 0.9 to 1.1 mm, and a microsieve downstream of the fine sieve , whose mesh size is about 0.3 mm, to filter even small impurities from the rinsing liquid. The purpose of such a filter arrangement is, during the circulation of the rinsing liquid, auszufiltem the largest possible proportion of impurities from the rinsing liquid. When pumping out the rinsing liquid, e.g. When changing from one rinsing program section to the next rinsing program section, the largest possible part of the impurities should be conveyed out of the washing compartment of the dishwasher in order to avoid clogging of the filter arrangement.

A disadvantage of the arrangement just described is that in practice only a portion of the impurities held in the filter assembly can be removed from the dishwasher during pumping. Therefore, it is necessary that at least some of the filter elements of the filter assembly are temporarily removed manually by a user of the dishwasher and cleaned manually. Around To spare the user of a dishwasher such unpleasant activity, it would be desirable if the filter assembly of the self-cleaning type would be.

A dishwasher with such a self-cleaning filter is known for example from US 3,179,116. The filter consists of a helical spring, wherein the distances of superimposed spiral sections are variably adjustable. When the rinsing liquid is circulated from the rinsing trough to the rinsing arms, the spring has a small length and thus small spiral section distances, so that contaminants detached from the ware are filtered by the spiral spring. When pumping the flushing liquid, which is caused by a change in the direction of rotation of the pump, the length of the coil spring is increased, whereby the distance between two adjacent spring sections increases, so that the adhering to the coil spring impurities flushed by the pumped flushing liquid into the interior of the coil spring and finally fed to the water drain. The changing of the length of the coil spring is made by water pressure generated in the lines, which is dependent on the direction of a circulation pump. During the circulation, only a slight water pressure is generated in a line connected to the spiral spring, whereby the coil spring remains shortened in length. When pumping, however, a high pressure is generated in the line connected to the spiral spring, whereby the coil spring is extended by a lever mechanism.

A disadvantage of the described arrangement is that the self-cleaning of the filter can only take place when changing from one to the next wash program section. However, if the filter is acted upon during a Spülprogrammabschnitts with a large amount of impurities, it can not be circulated by the pump enough rinse liquid for applying the dishes. The proposed arrangement therefore accepts that the cleaning effect of individual rinse program sections may be lowered.

From DE 36 33 441 A1 a device for wet washing garments is known, which has a designed as a gap filter lint filter and a fine filter. The lint filter consists of wires running parallel to one another and is arranged such that a liquid inlet opening above the upper end of the wire layer and one of two liquid outlet openings optionally immediately behind located at the bottom of the wire layer. The other outlet opening of the split filter leads to the inlet side of the feed pump and is located at any point of the bottom portion of the lint filter housing. The slit filter makes it possible to slip along the parallel wires to the lower end of the wire layer in front of the closable liquid outlet opening in the successive passing of the washing water in several program sections supplied Feus. From there, the impurities (fluff) at the end of the program sections by opening the liquid outlet through the effluent wash water flushed into the sewer. The fine filter only serves to retain washed out of the garments detergent in this.

Since the impurities during operation of a dishwasher vary much more in terms of their size and nature than is the case with the cleaning of garments, the filter described in DE 36 33 441 A1 can not be used in a dishwasher. Moreover, as in US Pat. No. 3,179,116, there is the disadvantage that it is only possible to clean the filter during the transition from one washing program to the next washing program.

Finally, DE-OS 2 249 603 and DE-OS 29 22 549 disclose filters for large-scale industrial use, which have self-cleaning properties due to their variable filter spacings or diameters.

The object of the present invention is to provide a water-conducting household appliance, in particular a dishwasher, which makes a manual cleaning of a filter element used for retaining impurities redundant, wherein the qualitative characteristics of the household appliance should be optimized in terms of energy consumption and cleaning performance. Furthermore, a method for operating such a water-conducting household appliance should be specified.

These objects are achieved by a water-conducting household appliance with the features of claim 1 and a dishwasher with the features of claim 10 and by a method for operating a water-conducting household appliance with the features of claim 13. Advantageous embodiments will be apparent from the dependent claims. According to the invention, a further water cycle is provided in the water-conducting domestic appliance, through which the rinsing liquid is circulated in accordance with the program control unit when the filter element is covered with impurities to cause the soiling of the filter element. The provision of a further water circulation makes it possible in an advantageous manner to carry out the self-cleaning of the filter element even during a wash program section, without having to carry out a pumping of the washing liquid currently being used in the household appliance. The provision of the further water cycle further reliably prevents contaminants detached from the filter element from migrating into the closed water loop, thereby avoiding the settling of these dissolved contaminants on the items to be washed.

In an expedient embodiment, the filter element is installed on or in a sump of the dishwasher such that it is well bathed by the rinsing liquid flowing or conveyed in the further water circuit. This ensures that all or at least a large part of the impurities that have settled on the filter element can be solved by the rinsing fluid circulated in the further water cycle.

In a further embodiment, the filter element has a variable mesh or gap width for providing a first and a second operating state, wherein the filter element in the first operating state, the filtering of impurities from the impurities in the water circulation carries out and in the second operating state, the release of the in the filter element trapped impurities when flowing through the funded by the further water circulation rinsing allows. Through the use of such a filter element, the cleaning of impurities is facilitated, as are easily removable by an altered mesh or gap width, in particular an increase, residues when flowing through the filter element with rinsing liquid. By contrast, by setting a narrow mesh or gap width, a spatially uniform layer of the filtration material is formed, which has a large absorption capacity and enables a high degree of cleaning of the rinsing liquid during circulation in the closed water cycle. In a further embodiment, it is provided to arrange a further filter element in the further water cycle. Characterized the detached from the filter element impurities are held in the further filter element of the further water cycle, whereby the flushing liquid flowing through the filter element is freed from more and more residues with increasing continuation of the circulation in the further water cycle. In other words, this means that the impurities from the closed water circuit, the sump and the filter element are eliminated, as a result, the wash ware is always applied with the best possible filtered rinsing liquid. In addition, the flushing capacity is not adversely affected by an increasingly clogging filter element, since a filter element with constant filter performance is created by actuating the further water circuit.

Conveniently, the further filter element is arranged in a collecting container. This makes it possible to collect the promoted in the wider water cycle impurities.

In a further embodiment, the further filter element has a variable mesh or gap width for providing a first and a second operating state, wherein the further filter element in the first operating state, the filtering of impurities promoted by the further water circulation Spülflüssigkeit and takes place in the second operating state Loosen the trapped in the other filter element impurities when flowing around the other filter element with rinsing fluid of the other water cycle allows. In other words, therefore, the further filter element is designed to be self-cleaning. This ensures a constant filtering performance of the second filter element during operation of the further water cycle.

According to another embodiment, the further water circuit is integrated into a water drain, so that the conveyed in the further water circulation rinse liquid can be supplied according to the program control unit either the dishwasher or the wastewater drain. In this case, the further water circuit is advantageously operated such that the further filter element is in the first operating state when the rinsing liquid is circulated in the household appliance. Accordingly, the further filter element is in the second operating state in which this allows a cleaning, wherein the impurities are supplied to the water drain. After a " store the contaminants in the further filter element or the collecting container, the impurities are transported from the household appliance.

In a dishwasher according to the invention with at least one substantially closed water circulation in the rinsing liquid in accordance with a program control unit is circulated, wherein the rinsing fluid during the circulation for filtering impurities by at least one filter element is conveyed, wherein the at least one filter element consists of thread elements, which in a tensioned state for cleaning the rinsing liquid and in a relaxed state for cleaning the filter element are arranged.

In a further embodiment, the thread elements are arranged on holding elements and in the tensioned state substantially in a plane or in a curved shape, for. B. cylindrical shape arranged.

The inventive method for operating a water-conducting household appliance, in particular a dishwasher, comprising a multiple program sections washing program, comprising the following steps: The filter element is operated during the course of the wash program in a first operating state in which this filtering the flushing liquid of impurities of the closed Water cycle takes over. In accordance with the program control unit or upon detection of a defined occupancy of the filter element with impurities of the further water cycle is activated and brought the filter element in a second operating state for detachment of impurities present in or on it.

With the method according to the invention, the same advantages are associated, as have been explained above in connection with the water-conducting household appliance.

In one embodiment of the invention, the second filter element is operated in activated further water cycle in its first operating state to free the conveyed in the further water circulation rinsing liquid from impurities.

In another embodiment, the further filter element after completion of the washing program or in accordance with the program control unit in a second Betriebszu- spent, in which the impurities located on or in the further filter element are flushed out of the further filter element by the rinsing liquid conveyed in the further water cycle.

According to a further embodiment, the rinsing liquid conveyed in the further water cycle is supplied to the water outlet during the second operating state of the further filter element.

The water-conducting household appliance according to the invention thus advantageously makes it possible to carry out a self-cleaning of the filter element of the closed water cycle even during a wash program section instead of basically waiting for the wash program end, as proposed in the prior art. As a result, the cleaning performance during a Spülprogrammabschnitts be kept at a consistently high level without the water-bearing household appliance additional fresh water would have to be supplied.

The invention and its advantages will be explained in more detail by way of example with reference to the drawing. Show it:

FIG. 1 shows a schematic representation of a water-conducting domestic appliance designed as a dishwasher with a further water cycle, FIG.

FIGS. 2a, 2b show a schematic illustration of a filter element which can be used by way of example in the domestic appliance shown in FIG. 1 in a side view and a cross section, wherein the filter element is shown in a first operating state, and

3a, 3b is a schematic representation of an example used in the household appliance shown in FIG. 1 filter element in a side view and a cross section, wherein the filter element is shown in a second operating state.

In Fig. 1, a dishwasher 1 is shown in a schematic view. The dishwasher 1 essentially comprises a washing compartment 2, in which not shown is arranged Spülgutskreislauf 6, a (not shown in the figure) water inlet and a water outlet 11. The items to be washed is arranged in the washing compartment 2 between washing or spraying 3. Below the items to be washed and the washing arms 3, a rinsing pan 4 is arranged, which passes rinsing liquid present in the washing compartment in a sump 5. The sump 5 belongs to the Spülflüs- sigkeitskreislauf 6, in which the rinsing liquid 7 required for a washing process is circulated. During a washing process, which may include the program sections pre-rinsing, cleaning, intermediate rinsing and rinsing, the sump 5 is removed via a line 8 rinsing liquid and passed through a filter element 14 to a pump 9. After passing through a through-flow heater (not shown), the flushing liquid is led by the pump 9 via lines 10 to the washing arms 3 and sprayed by them into the flushing space 2. In the washing compartment 2, the rinsing liquid 7 then passes through the rinsing tank 4 back into the sump 5. With the sump 5, the water outlet 11 is connected, via which the rinsing liquid can be derived. For example, a portion of the rinsing liquid or the entire rinsing liquid is discharged via the water outlet 11 after each wash cycle. A filling of the sump is done with the help of the water inlet, which provides fresh water. In addition, the dishwasher 1 may have further, not shown in the figure elements, such as a device for the addition of detergent, a water softening system, sensors and the like.

By applying the rinsing with rinsing liquid impurities are removed from this, which initially collect in the sump 5, to then be filtered by the operation of the pump 9 in the filter element 14 from the circulating rinsing liquid. Depending on the degree of soiling of the items to be washed or the number of wash program sections already carried out, the filter element 14 is more or less exposed to impurities. Under certain circumstances, this can lead to insufficient pumping liquid being able to be conveyed out of the sump 5 by the pump 9, as a result of which the wash ware is consequently subjected to less washing liquid, so that the wash result worsens.

In order to avoid a manual cleaning of the filter element 14, this is designed as a self-cleaning filter element. Such a self-cleaning filter element is shown by way of example in FIGS. 2 and 3, wherein in FIG. 2 a first operating state is shown, in which a filtering of the conveyed through it rinsing liquid is effected. FIG. 3 shows the filter element in a second operating state in which self-cleaning is possible. The filter elements shown in the figures are traversed perpendicular to the sheet plane.

For this purpose, the filter element has holding elements 32 arranged in a housing 30 formed with guides 31, between which thread elements 33, e.g. made of metal, a plastic or other material, are arranged. By tensioning the thread elements 33 results in the parallel alignment shown in Fig. 2a with a defined distance from each other. Depending on the desired filter effect, the distance can be defined by fastening the thread elements 33 in the holding elements 32. The tensioning and relaxing of the thread elements 33 with the holding elements 32 via corresponding devices, for. As spindles or hydraulic devices. In the side view of Fig. 2b it can be seen that all thread elements 33 lie in a plane, whereby a good filtering effect is ensured. If at least one of the two holding elements 32 is moved in the direction of the other holding element, then the thread elements 33 can relax in the manner shown in the figure, whereby the distances are increased in more or less random manner. When flowing through the filter element with rinsing liquid in the second operating state, the impurities held on or in it can then be rinsed out.

The self-cleaning process of the filter 14 can either be controlled by a program control unit (not shown in the figures) or upon detection of a defined occupancy of the filter element 14. With increasing occupancy of the filter element 14, the funded by the pump 9 flushing liquid is reduced. By the measured after the filter element 14 funded amount of flushing liquid can then be closed to the assignment of the filter element.

For cleaning the filter element 14, as described in connection with FIG. 3, the filter element 14 is brought into its second operating state. At the same time a further pump 13 is set in motion, which promotes the flushing liquid 7 located in the sump 5 by a further water circuit 15. The pump 13 is located in the further water circuit 15, which also has a collecting container 16, in which a further filter element 17 is arranged. On the output side is the Sump 16 via a valve 18 selectively connected to the water outlet 11 or a line 20 which promotes circulating in the further water circulation 15 rinsing liquid back into the sump 5.

In order to be able to effect a self-cleaning of the filter element 14, it has to be flowed around in a suitable manner by the rinsing liquid conveyed through the further water circuit 15. In practice, the filter element 14 will therefore be arranged at a suitable location in the conduit 8 or directly on or in the sump 5.

The detached from the filter element 14 impurities are collected via the pump 13 and the line 19 through the further filter element 17, which is preferably also carried out self-cleaning. The funded by the further water circulation 15 rinsing liquid is thus cleaned at the outlet of the collecting container 16, and, if the water cycle was actuated during a Spülprogrammabschnitts, fed to the sump 5. After a certain period of time, the further water circuit 15 can be deactivated, at the same time the filter element 14 being returned to its first operating position. Subsequently, the interrupted rinse program section can be continued. Of course it is also possible to carry out the self-cleaning of the filter element 14 at the end of a washing program section. In this case, for example, the rinsing liquid cleaned by the further filter element 17 could be used for the next rinsing program section, so that the supply of fresh water could be dispensed with.

Since now detached from the items to be washed contaminants are trapped in the other filter element 17, and the cleaning effect of the other filter element 17 deteriorates with increasing operating time of the further water circuit 15, a self-cleaning of the other filter element 17 always takes place when the rinsing a Spülprogrammabschnitts the water outlet 11 is to be supplied. With the appropriate switching of the valve 18 thus the further filter element is set in its second operating state, so that the pumped from the sump 5 via the pump 13 rinsing liquid can replace the trapped in the other filter element 17 impurities, which is then fed to the water outlet. LIST OF REFERENCE NUMBERS

1 dishwasher

2 washing room

3 spray arm

4 rinse tank

5 pump pot

6 water cycle

7 rinsing liquid

8 line

9 pump

10 line

11 water drainage

13 pump

14 filter element

15 water cycle

16 collection containers

17 filter element

18 valve

19 line

20 line

30 filter housing

31 guide element

32 retaining element

33 thread element

Claims

claims

1. Water-conducting household appliance, in particular dishwasher (1) with at least one substantially closed water circuit (6), in the rinsing liquid (7) in accordance with a program control unit is circulated, wherein the rinsing fluid during the circulation for filtering impurities by a filter element (14) conveyed characterized in that a further water circuit (15) is provided, through which the rinsing liquid is circulated in accordance with the program control unit, when the filter element (14) is covered with impurities to cause the deslagging of the filter element (14).

2. Household appliance according to claim 1, characterized in that the filter element (14) is installed on or in a sump (5) of the dishwasher, that this is well umspülbar of the further water cycle (15) flowing rinsing liquid.

3. Household appliance according to claim 1 or 2, characterized in that the filter element (14) has a variable mesh or gap width for providing a first and a second operating state, wherein the filter element in the first operating state, the filtering of impurities from in the Water cycle (6) located impurities and in the second

Operating state, the release of the trapped in the filter element (14) impurities when flowing through the funded by the further water circulation (15) rinsing allows.

4. Household appliance according to one of the preceding claims, characterized in that the further water circuit (15) has a further filter element (17).

5. Household appliance according to one of the preceding claims, characterized in that the further filter element (17) is arranged in a collecting container (16).

6. Household appliance according to claim 4 or 5, characterized in that the further filter element (17) has a variable mesh or gap width for providing a first and a second operating state, wherein the further filter element (17) in the first operating state, the filtering of impurities the rinsing liquid conveyed in the further water circuit (15) makes possible, in the second operating state, the release of the impurities trapped in the further filter element (17) when the further filter element (17) flows around with rinsing liquid of the further water circulation (15).

7. Household appliance according to one of the preceding claims, characterized marked, that the further water circuit (15) in a water outlet (11) is integrated, so that in the further water cycle (15) funded rinsing liquid in accordance with the program control unit either the water-conducting household appliance or the water outlet (11) can be fed.

8. Household appliance according to one of the preceding claims, characterized in that the at least one filter element (14, 17)) consists of thread elements (33) which in a tensioned state for cleaning the rinsing liquid (7) and in a relaxed state for cleaning the Filter element (14, 17) are arranged.

9. Household appliance according to claim 8, characterized in that the thread elements (33) are arranged on holding elements (32) and in the tensioned state substantially in a plane or in a curved shape, for. B. cylindrical shape, are arranged.

10. Dishwasher (1) with at least one substantially closed water circuit (6), in the rinsing liquid (7) in accordance with a program control unit is circulated, wherein the rinsing fluid during the circulation for filtering impurities by at least one filter element (14, 17) is conveyed , characterized in that at least one filter element (14, 17) of thread elements

(33) which are arranged in a tensioned state for cleaning the rinsing liquid (7) and in a relaxed state for cleaning the filter element (14, 17).

11. Dishwasher (1) according to claim 10, characterized in that the thread elements (33) are arranged on holding elements (32) and in the tensioned state substantially in a plane or in a curved shape, for. B. cylindrical shape, are arranged.

12. Dishwasher (1) according to claim 10 or 11, characterized in that the dishwasher according to a water-conducting household appliance according to one or more of claims 1 to 7 is executed.

13. A method for operating a water-conducting household appliance, in particular a dishwasher (1), with a plurality of program sections comprehensive wash program, wherein the filter element (14) is operated during the course of the wash program in a first operating state in which this is a filtering of the washing liquid Impurities of the water cycle (6) takes over, and in accordance with the program control unit or upon detection of a defined occupancy of the filter element (14) with impurities activated the further water circuit (15) and the filter element (14) in a second operating state for detaching the in or on it existing impurities is brought.

14. The method according to claim 13, characterized in that the further filter element (17) is operated with activated further water cycle in its first operating state to free the conveyed in the further water cycle rinsing fluid from impurities.

15. The method according to claim 13 or 14, characterized in that the further filter element (17) is spent after completion of the wash program or in accordance with the program control unit in a second operating state, in which located on or in the further filter element (17) impurities by the in the second water cycle (15) funded rinsing fluid from the other

Filter element (17) are rinsed out.

16. The method according to claim 15, characterized in that in the further water circuit (15) funded rinsing fluid during the second operating state of the further filter element (17) is supplied to the water outlet (11).