EP2378942A2

EP2378942A2 - Method for operating a dishwashing machine

Info

Publication number: EP2378942A2
Application number: EP09795372A
Authority: EP
Inventors: Helmut Jerg; Michael Rosenbauer
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2008-12-19
Filing date: 2009-12-04
Publication date: 2011-10-26
Also published as: DE102008055018A1; CN102256526A; WO2010079026A2; WO2010079026A3; RU2011127141A

Abstract

The invention relates to a method for operating a dishwashing machine, comprising at least the following steps: - water is supplied to the dishwashing machine from a water supply network, said water is softened in a water softening device (6) of the dishwashing machine, the softened water is applied to items for washing or drying, said softened water applied to the items for washing or drying is buffered at least once in a tank (19) and said softened water stored in said tank (19) is applied to items for washing or drying.

Description

Method for operating a dishwasher

The invention relates to a method for operating a dishwasher.

Dishwashers are known to have water softening systems with which the fresh water used during a rinse cycle is softened.

For example, DE 10 2004 019 330 A1 discloses a dishwashing machine with a water softening system to which a water quantity measuring device is assigned. The measuring device detects the actual amount of fresh water used per wash cycle. After reaching a maximum Durchspülmenge the softening plant starts under high energy expenditure a regeneration process to free the water softening system from the absorbed lime. However, the use of such a measuring device increases the component and cost.

The object of the invention is to provide a dishwasher in which the energy expenditure associated with the regeneration is reduced.

The object is achieved by a method with the steps of claim 1. Preferred embodiments of the invention are disclosed in the subclaims.

According to the patent claim 1 fresh water is supplied from the water supply network of the dishwasher and softened in a softening device of the dishwasher. The softened water is applied to items to be cleaned or dried. At least once, the softened water applied to the items to be cleaned or dried is cached in a tank. The cached in the tank, softened water is then, for example, in a subsequent wash program, again applied to be cleaned or to be dried items. Therefore, according to the invention, there is a temporary storage and reuse of the already softened water. The softening device of the dishwasher can therefore be charged with a reduced amount of fresh water from the water supply network. Accordingly, the number of between the regenerating softening operations are increased, whereby with a larger number of rinses performed in the arithmetic mean, the energy consumption per cycle is reduced.

In a particularly preferred process management, the softened water temporarily stored in the tank can be passed directly into a rinsing container which serves to receive items to be cleaned. The feeding of the cached water in the tank can preferably be done bypassing the softening device, d. h., the cached water is passed to the water softening device directly into the washing.

The cached in the tank water can be used in at least one program step of a subsequent, a plurality of program steps comprehensive wash program. Such a wash program may include the program steps pre-wash, clean, intermediate rinse and dry. Preferably, the water stored in the tank can be used in a pre-rinse step of the rinse program. The cached in the tank water may have been passed in the previous wash program during or after execution of a Zwischenspülschrittes in the tank.

In the design of a softening capacity of the softening device, among other things, the amount of fresh water used per rinse program and the water hardness must be taken into account. In a metrologically complex embodiment, the regeneration process of the softening device can take place when a measuring sensor has detected a maximum softenable, guided by the softening device amount of fresh water. In order to avoid such a measuring or signal technical effort, preferably the number of rinsing programs to be carried out until the regeneration process of the softening device is determined empirically in a control device of the dishwasher. Correspondingly, the regeneration process of the softening device can be carried out according to a predetermined or predefinable number of water softening processes by the control device.

When using water cached in the tank, the number of softening operations, in particular by an additional softening process, can be increased become. When determining the number of softening processes until the regeneration process, the fact is taken into account that the amount of fresh water required per wash program is reduced from the water supply network.

In a preferred method, the washing container can be repeatedly filled with water when performing a washing program, in particular in

Connection with the respective program steps Pre-rinsing, cleaning, intermediate rinsing and / or drying. The softening capacity of the softening device can be designed so that after at least every second, in particular every third

Carrying out a wash program, a regeneration process in the softening device takes place.

An exemplary embodiment of the invention is described below with reference to the appended FIG. 1, which shows in a schematic block diagram a dishwasher with a tank or a liquor storage tank.

1 shows schematically a dishwasher with a washing compartment 1 delimiting a washing compartment. In the washing compartment of the washing container 1, not to be cleaned, to be cleaned dishes in dish racks 3, 5 are arranged. In the washing container 1 shown, two spraying arms 7, 8 provided in different spraying levels are arranged by way of example, via which the washware to be cleaned is supplied with washing liquid.

In the Spülbehälterboden a pump pot 1 1 is provided with associated circulating pump 13, which is connected via supply lines 14, 15 fluidly connected to the spray arms 7, 8. The arranged in a circulation line 9 circulating pump 13 is a heating element 12 downstream, such as a water heater, which is also referred to as water heater. The sump 11 is also connected via connecting pieces with a, connected to the water supply network fresh water supply line 16. In the fresh water supply line 16, a softening device 6 is connected upstream of a main valve 4 in the flow direction. The sump 1 1 is also connected via a further connection piece with a drain line 17 in connection, in which a drain pump 18 is arranged for pumping out rinsing liquid from the washing compartment 1.

The rinsing container 1 further has on its side wall 20, which is on the right in FIG. 1, on the outside a tank or a so-called float storage 19, which is likewise thermally coupled in contact with the rinsing container 1. Already softened rinsing liquid which is no longer required after the execution of a partial program step, for example a final rinse, can be temporarily stored in the float storage 19. The cached rinsing liquid is used in the subsequent rinsing program or rinse cycle, for example in a pre-rinsing step.

The circulation line 9 forms, together with the supply lines 14, 15 and the washing compartment a closed hydraulic circuit in which the rinsing liquid circulates in partial program steps with liquid insert and acts on the spray arms 7, 8 the items to be washed. Downstream of the arranged in the circulation line 9 heating element 12 branches off at a branch point 21, a connecting line 23, which leads to the fleet memory 19. In the branching point 21, a water separator 25 is provided, which is shown here by way of example as an electromagnetically actuated three-way switching valve 25. The three-way switching valve 25 connects in a first switching position shown, the circulation line 9 leading to the hopper 19 connecting line 23 and interrupts the above-mentioned hydraulic circuit. In contrast, in a second switching position, not shown, the three-way switching valve 25, the connection to the fleet memory 19 is interrupted, while the circulation line 9 is connected to the supply lines 14, 15. All device components, such as the water diverter 25, the circulation pump 13 or the softening device 6, can be controlled via a control device 29.

As is further apparent from FIG. 1, the softening device 6 has an ion exchange container 26 with ion exchange material as well as a regenerant container 27, which is preceded by a water switch 28. Depending on the switching position, this leads the fresh water either directly to the ion exchange container 26 or to the regeneration medium container 27. During a normal rinsing operation, the fresh water from the fresh water supply network is passed through the ion exchange container 26 the softening system, in which the fresh water is softened by the ion exchange material. Subsequently, the softened soft water is introduced via the supply line 16 into the washing container 1 and thus into the hydraulic circuit of the dishwasher.

The softening capacity of the softening device 6 is exhausted after a number of washing programs executed. In this case, to regenerate the ion exchange material in the ion exchange vessel 26, a predetermined amount of fresh water, about 3-5 liters, is fed into the regenerant vessel 27. The regenerant tank 27 contains a regenerant that dissolves in the water. The resulting brine is directed into the ion exchange vessel 26 in which the ion exchange between the regenerating sole and the ion exchange material takes place. The regenerant container 27 can be filled with regenerating agent via a closable opening.

The dishwasher can be operated with a washing program having a plurality of program steps, namely pre-rinsing, cleaning, intermediate rinsing, rinsing and drying. In this case, the washing container 1, in particular when changing from one to the following program step with water from the water supply network or with the water stored in the fleet memory 19 can be filled.

In a first program step, the pre-wash V, water already stored in the liquor storage 19 can, for example, be returned to the rinse tank 1. As stated above, the fleet storage 19 already contains softened rinsing liquid, which is no longer needed after carrying out an intermediate or final rinse step in a previous rinse program.

For filling the washing container 1 with the cached in the fleet memory 19 water, the three-way switching valve 25 is shown in FIG. 1 brought into the switching position shown and set the circulation pump 13 out of operation. The cached water can then, for example under gravity, be performed in the washing 1. Its flow path therefore extends starting from the float storage 19 via the connecting line 23 and the circulation line 9 into the sump 11 of the Washing. A renewed action on the softening device 6 by means of the already softened, cached water is thus not carried out. After execution of the pre-rinsing step, the water that is no longer needed is fed via the drain line 17 into the sewage network.

In the subsequent cleaning step R, water from the water supply network is softened via the softening device 6 and guided along the supply line 16 into the pumping pot 11 of the washing container 1. After execution of the cleaning step R, the water is passed through the drain line 17 in the sewer network. Subsequently, the intermediate rinsing step Z, for which again fresh water is passed from the fresh water supply network through the softening device 6 in the washing compartment 1. After execution of the final rinse step K, however, the water that is no longer needed is not directed into the sewage network, but temporarily stored in the float storage tank 19. For this purpose, the circulation pump 13 is put into operation, while the three-way valve 25 remains in the switching position shown, whereby the water can be pumped into the fleet storage 19. Subsequently, the drying step for drying the items to be washed takes place. The thus cached water is reused in the pre-rinse step of the subsequent rinse program.

A regeneration process of the softening device 6 can be carried out, for example, after three passes of a washing program or of variants of a washing program, which with regard to the process parameters, such as e.g. Duration or maximum temperature, the

Steps Pre-rinse V, Purge R, Intermediate rinse Z, Rinse rinse K and Dry T differ. This regeneration process can take place during the purification step R, so that in particular it is ensured that softened water is available during the rinsing K and a stain-free drying result is ensured.

For the regeneration process, a further, additional filling with fresh water from a water supply network is required. By this additional filling cold, about 15 ° C warm water is introduced into the dishwasher, resulting in an unwanted cooling inside the dishwasher. This cooling must be compensated by a corresponding heating power again, so that, for example, the rinse step K, the predetermined final temperature is reached in the subsequent drying step T to ensure reliable drying of the ware. Thus, each regeneration of the softener increases the energy consumption of the dishwasher.

For the execution of the washing program in the dishwasher shown in FIG. 1, for example, a total amount of rinsing liquid of 10 liters may be required. These

Total Spülflüssigkeitsmenge is made up of the flushed liquid stored in the fleet memory 19, which may be in the order of 2 liters and is already softened, and from a newly supplied from the water supply network amount of fresh water, which may be exemplary here at 8 liters together.

The advantages resulting from the combination of water softening device 6 and tank 19 of the dishwasher according to the invention are particularly clear in comparison with a dishwashing machine which does not have a tank 19, but otherwise is identical in construction. In contrast to FIG. 1, in this case, the entire rinsing liquid required for the rinsing program is to be supplied as a fresh water quantity. This means that when the total amount of rinsing liquid required for the rinsing program is 10 liters, a fresh water quantity of 10 liters must be introduced into the rinsing container 1 via the softening unit 6.

For a softening capacity of the water softening unit 6, which allows, for example, a maximum Flüssigkeitsdurchspülmenge of 40 liters, therefore, the following facts arise: The softening capacity of the water softener 6 is already depleted in the comparative dishwasher without Fleottenspeicherereinsatz after four softening operations. In contrast, the softening capacity in the dishwasher with fleet storage insert is exhausted only after five softening operations.

In the comparative dishwasher without Flextenspeicherereinsatz the number n, from softening operations to the regeneration process in the controller 27 is set to four.

In contrast, in the dishwasher according to the invention with a fleet storage unit, account is taken of the fact that only 8 liters are available due to the liquor storage tank 19 Fresh water, and not 10 liters of fresh water, each wash program are required. The number n of softening processes to be carried out can therefore be increased by one softening process to five, which leads to a reduction of the energy expenditure in the regeneration of the softening device and thus the energy requirement of the dishwasher.

LIST OF REFERENCE NUMBERS

1 bobbin

4 main valve

3 crockery basket

5 crockery basket

6 water softening system

7 spray arm

8 spray arm

9 circulation line

11 pump pot

13 circulation pump

14 supply line

15 supply line

16 fresh water supply line

17 drain line

18 lye pump

19 lot memory

20 sidewall

21 branch point

23 connection line

25 water switch

26 ion exchange containers

27 regenerant container

28 water switch

29 control device n, number of softening operations that are feasible up to a regeneration process

Claims

A method for operating a dishwasher, comprising at least the following steps: - it is water from a water supply network of

Dishwasher supplied, the water is softened in a softening device (6) of the dishwasher, the softened water is applied to be cleaned or to be dried ware, it is at least once applied to the cleaned or to be dried ware, softened water in a tank (19) cached, and it is stored in the tank (19), softened water applied to be cleaned or dried items to be washed.

2. The method according to claim 1, characterized in that when it is filled with water stored in the tank (19), it is passed into a washing compartment (1) of the dishwasher serving to receive items to be cleaned, in particular bypassing the softening unit (6). ,

3. The method according to claim 1 or 2, characterized in that a regeneration of the softening device (6) takes place during a washing program comprising a plurality of program steps (V, R, Z, K; T).

4. The method according to claim 3, characterized in that the regeneration of the softening device (6) takes place during a cleaning step R of the washing program.

5. The method according to any one of claims 1 to 4, characterized in that in the tank (19) stored water in at least one program step (V, R, Z, K, T) of a subsequent rinse program comprising a plurality of program steps.

6. The method according to any one of claims 1 to 5, characterized in that in the tank (19) stored water in a pre-rinsing step (V) of a plurality of program steps (V, R, Z, K, T) comprehensive rinse program is used ,

7. The method according to any one of claims 1 to 6, characterized in that at each program step (V, R, Z, K, T) of a washing program, a filling with water from a water supply network or in the tank (19) stored water is performed ,

8. The method according to any one of claims 1 to 7, characterized in that after a predetermined or predetermined number (ni) of softening processes of water, a regeneration of the softening device (6) is performed.

9. The method according to claim 8, characterized in that when using in the tank (19) stored water, the number (ni) is increased.

10. The method according to any one of claims 3 to 9, characterized in that when carrying out a washing program 2 to 5 fillings are performed with water.

11 Method according to one of claims 3 to 10, characterized in that after at least every second, in particular every third implementation of a

Rinsing program a regeneration of the softener is performed.

12 dishwasher, adapted for carrying out a method according to one of claims 1 to 1 1.