EP1354549B1 - Cleaning agent dosing device for dishwashers - Google Patents

Description

The present invention relates to a metering device for metering a two-component Geschirreinigungsmittels in a dishwasher, in particular transport machine or belt machine, wherein the Geschirreinigungsmittel has at least one alkaline component and at least one dispersant and optionally at least one complexing agent.

Generic metering devices are used in a wide variety of types of commercial dishwashers, in particular conveyor and belt machines. In this type of dishwashers, the items to be washed are usually either transported in baskets or on a conveyor belt through different rinsing zones of the dishwasher and thereby cleaned. In the cleaning process, among other things, dishwashing detergents are used, which are composed of different components, whereby these individual components or chemical substances have different tasks, such as e.g. on the one hand the dirt removal, on the other hand serve the protection of the machine and the dishes. In prior art dosing or dishwashing machines, dishwashing detergents are used in which the individual components are mixed in a fixed ratio to one another. One usually speaks of such Geschirreinigungsmitteln of so-called "mono products".

The alkaline component usually present in the generic dishwashing detergents mainly serves to remove dirt, and may additionally contain corrosion inhibitors which serve to protect the machine and its parts against the aggressiveness of the alkali component. As a further component of the Geschirreinigungsmittels a so-called dispersant is usually provided. This keeps the debris removed from the dishes in the rinse liquor, preventing it from re-attaching to the dishes. In addition to these two standard components, a complexing agent is generally provided as a further component of the dishwashing detergent. This binds the calcium-magnesium ions in the water and thereby prevents their precipitation on the heating rods and the machine walls and thus the calcification of the dishwasher. In addition to these three components usually provided by default can also be an additional disinfection or Bleaching component may be provided to chemically-thermally disinfect the dishes chemically or in conjunction with an elevated temperature.

In the prior art, the dishwashing detergent is always used as a ready-mixed product of the individual components necessary for the various tasks. As a result, in the prior art, as a rule, overdose of at least one component occurs, as the following examples show:

In a dishwasher, which is usually faced with increased starch deposition or with dried-on food residues on the dishes, an increased amount of Geschirreinigungsmittel must be dosed in order to achieve an optimal result. However, since only the alkaline component has a noticeable effect on the release of starch or dried-on food residues, the overall increase in the dosage of the dishwashing detergent leads to an overdose of all other components of the dishwashing detergent.

If a dishwasher is constantly operated with very hard or hard water, it must be dosed to prevent the formation of lime soap and to prevent the precipitation of lime (combined with defective heating rods, encrusted machines) as much dishwashing detergent as for the complexing (binding) of lime is necessary. This in turn automatically leads to overdosing of the other components present in the dishwashing detergent. Another example of this overdosing is given when a dishwasher runs, for example, in continuous operation from 9 to 19 clock, without the rinsing liquor would be replaced during this time. In this example, the dosage of the dishwashing detergent must be set so high that the cleaning success is satisfactory even at the end of the operating time. In order to keep the dirt in the heavily loaded wash liquor and to prevent it from re-attaching to the dishes to be washed, an increased amount of dispersant is needed so that the other components of the Geschirreinigungsmittels are in turn overdosed.

The prior art thus often leads to the overdosing of individual components of the Geschirreinigungsmittel, which has a negative impact on the overall balance of the dishwashing process, both in ecological and economic terms.

The object of the present invention is therefore to provide a metering device with which the abovementioned disadvantages of the prior art are avoided.

This is inventively achieved in that the metering device (1) has at least two separate inlets for each at least one component of the Geschirreinigungsmittels and a control or regulating device, wherein the control or regulating device, the individual components in one, preferably in advance and / or variable , adjustable amount ratio dosed each other in the dishwasher.

By means of the metering device according to the invention, it is possible to introduce the individual components of the dishwashing detergent via the separate inlets provided in the metering device, for example from separate storage containers, supply lines or the like, independently of one another and to dose them individually from there, whereby both economically and also From an ecological point of view, optimal adaptation of the dosage to the particular conditions in which a dishwasher is used becomes possible. Thus, the composition of the dishwashing detergent can be adapted, inter alia, to the locally encountered degree of hardness of the water used, to the present degree of soiling of the dishes as well as to the total volume of the daily amount of dishes to be washed. Here, the quantitative ratio can be understood as meaning both a volume ratio and a mass ratio of the individual components to one another. Now it is off the US 3,490,467 It is already known to dose an alkaline dishwashing detergent and a bleaching or chlorine-containing agent separately from one another into a dishwashing machine. However, this only serves to prevent the two mentioned agents from interfering with each other during prolonged storage each other negatively in their effect. An adaptation of the dosage of the components of the dishwashing detergent to the respective task, as is possible with the metering device according to the invention, by the in the US 3,490,467 not disclosed. For example, with the in the US 3,490,467 Although shown an increased amount of the device alkaline rinsing agent are added in order to achieve improved replacement of larger amounts of dirt from the dishes. However, once the dirt has been removed from the dishes, the dirt will, due to the lack of a suitable dosage of dispersant, again adhere to the already washed dishes. A similar problem arises from the lack of the complexing agent, as can not be responded to different degrees of hardness of the water with the device shown.

Another metering device according to the preamble of claim 1 is ready US 3,896,827 known.

In a preferred embodiment, in a dishwasher with a commonly present main wash zone and a main wash tank, it is provided that the metering device doses the components of the dishwashing detergent into the main wash zone, preferably into the main wash tank. As a result, the components of the dishwashing detergent specifically added by the metering device are introduced directly into the area of the dishwasher in which they are essentially required.

It is furthermore particularly advantageous that the metering device has a memory and a data input device, preferably a keyboard, wherein at least one, preferably different, quantitative ratio (s) of the individual components as part of at least one washing program, preferably different ones, are stored in the memory via the data input device Rinsing programs, entered and stored in this is (are), wherein the control or regulating device dosed the individual components depending on the (the) in the rinse program (in the rinse programs) stored ratio (se). In this form of training, it is thus possible to put together different washing programs, which are especially geared to the particular needs of the once installed on-site dishwasher. In this case, it is particularly favorable that the quantity ratio (s) can be variably entered (depending on the time of day) into the rinse program (s) and can be stored in this rinse program (s). As a result, the dosage of the individual components can be adapted to the daily schedule of the flushing requirement. This is for example cheap, if in the morning slightly soiled breakfast dishes, lunch heavily soiled lunch dishes, etc. is to rinse. In a further embodiment, it can likewise be provided that the wash program can be interrupted and at least one predefinable special wash program can be played during the interruption of the wash program.

This is particularly advantageous when conditions other than the normal rhythm have to be spontaneously addressed, or e.g. a basic cleaning of the dishes should be made.

In addition to the pure use of the metering device according to the invention as a control device for implementing predefined washing programs can also be provided that the metering device is used as a control device by having at least one measuring device for determining at least one controlled variable. In this case, the controlled variable provides information about the instantaneous state of the rinsing liquor present in the dishwasher and can be used, for example. be used by the control or regulating device, if necessary, continuously adjusts the measured controlled variable by dosing at least one component of the Geschirreinigungsmittels to a predetermined, preferably time-variable setpoint. It is thereby achieved that preferably always at any time the optimum e.g. ensured in the rinse program concentrations of the individual components of the dishwashing detergent in the rinse liquor. In a further development of this control device can also be provided that the control or regulating device from a comparison of the measured controlled variable with the setpoint to be dosed amount of a first component of the Geschirreinigungsmittels, preferably the alkaline component, and from there over a predeterminable ratio to dosing amounts of the other components of the Geschirreinigungsmittels determined. As a result, the individual components are kept in the currently desired mixing ratio to each other. The desired setpoints may be e.g. also be stored in the washing program.

As a measuring device or controlled variable various variants known in the prior art can be realized. Thus, on the one hand, a pH measurement is possible. Alternatively, however, it can also be provided that the measuring device is an electrical conductivity probe and the controlled variable is the electrical conductivity of a rinsing water composition or a rinsing liquor. The measurement of the controlled variable is usually carried out in the main tank of the dishwasher, since the optimum concentration of the individual components of the dishwashing detergent must be ensured here as a rule.

In addition to the dosage of the already mentioned and commonly used three components of the Geschirreinigungsmittels the metering device can also be used for the controlled addition of other substances in the dishwasher. Thus, e.g. be provided that the metering additionally dosed at least one bleach and / or disinfectant and / or at least one rinse aid together with or at spatially separate locations of the Geschirreinigungsmittel in the dishwasher. In this case, the rinse aid is usually introduced into the rinse-aid zone or into the rinse-aid tank, while the bleach and / or disinfectant can also be injected into the main wash zone or into the main wash tank in addition to the dishwashing detergent. The rinse aid, along with the rinse water after the actual cleaning, is applied to the dishes as a final step to prevent beading and the resulting drop marks and to accelerate the drying. He is thus an independent of the actual Geschirreinigungsmittel in the Nachspülwasser metered product.

Further features and details of the present invention will become apparent from the description of the single figure. This shows a dishwasher with an embodiment of a metering device according to the invention.

In the figure, a dishwasher 2 and a metering device 1 according to the invention is shown schematically. The dishes 31 to be washed are moved, for example, in baskets 12 on a conveyor belt through the dishwasher 2. In this case, it passes successively the prewash zone 3, the main wash zone 4, the final wash zone 5 and 6 Nachspülzone and the drying zone 7. On his way from the prewashing zone 3 to Nachspülzone 6 the dishes are each sprayed from here only simplified rinsing or spray nozzles 9 shown. The spilled liquids are removed via the schematically indicated lines in each case from the prewash tank 13, the main tank 14, the wash tank 15 and the rinse tank 16. After the sprayed liquid has passed the harness, it essentially returns to the respective underlying tank 13 to 16. The tanks are arranged in a cascade one behind the other, whereby fresh water heated from the boiler 10 is first introduced from the fresh water supply line 11 into the final washing tank 16 and here mixed with rinse aid in a low concentration as explained in more detail below. From the final rinse tank 16 that runs along Rinse aid added water over the overflow 17 in the clear wash tank 15, from there in turn in the main tank 14 and then in the prewash tank 13. In pre-wash tank 13 reaches the purge solution maximum pollution and leaves over the overflow of the drain 18, the dishwasher 2. The harness learns in the pre-wash zone 3, a pre-cleaning, in which the adhering to the dishes food leftovers are loosened. The actual washing process takes place in the main washing zone 4. Here the dishes 31 are completely cleaned of the adhering dirt. Subsequently, in the final wash zone 15, the washing of the still adhering to the dishwashing rinse, whereby a comparison with the final rinsing tank 16 increased concentration of dishwashing detergent in the wash tank 15 is achieved. In the final rinse zone 6, the cleaned dishes are sprayed with fresh water and a rinse aid dissolved in low concentration before being dried in the drying zone 7 by means of the blower 8. The rinse aid lowers the surface tension and thereby prevents staining on the dishes 31.

From the flushing process described in this way, it can be seen that the rinsing liquor present in the various tanks 13 to 16 is permanently diluted by the trailing fresh water if appropriate countermeasures are not provided. The setting of the desired concentrations of dishwashing detergent or other components such as rinse aid in the individual tanks is realized and monitored by the inventive dosing device 1 both after the replacement of the entire rinsing liquor and during the normal operation of the dishwasher 2. The metering device 1 is for this purpose connected via feeds 24 with storage containers 19 to 23. In the illustrated embodiment, the container 19 contains the alkaline component, the dispersing agent in the container 20, the complexing agent in the container 21, the disinfecting component in the container 22 and the rinse aid container 23. The introduction of the individual components to be metered takes place in the example shown here via flow-metering pumps 25. In another embodiment, not shown here, however, the pumps 25 can also be replaced by flow-measuring valves, if the inflow of the individual components is ensured by means of gravity , Alternatively, valves or pumps with a constant flow rate or flow rate can be used, the control or regulating device 1, the flow rate, for example, depending on the delivery time of the pump or the Opening time of the valves calculated. As pumps come a variety of types such as peristaltic pumps, diaphragm pumps, piston pumps or the like in question. The control and the flow rate monitoring of the pumps 25 and the valves used in their place is realized in all variants by the control or regulating device 27. This is, as shown schematically, connected to the data input device 28, the data memory 29 and optionally to a display 30.

The individual components from the containers 19 to 22 are individually sucked in the example shown by pumps 25 via the inlets 24 in the metering device 1 and from there via supply lines 32 into the main tank 14, while the rinse aid from the container 23 is via a separate line 33 is introduced into the final washing tank 16. With the system shown schematically in the figure, all substances from the containers 19 to 23 can be metered independently or else in dependence on each other. Alternatively to the variant shown in the figure, individual components such as e.g. the alkaline component, the dispersant and the complexing agent are mixed in the metering device 1 according to the desired ratio and introduced via a common supply line 32 in the Hauptwaschtank 14. In all these variants, it is achieved according to the invention that for each dishwashing machine a recipe adapted to the local needs is realized. The various mixing ratios or formulations and the time sequence or the change to be made over the course of this formulation is stored in the form of different, preferably up to 8 different, rinse programs. The rinsing programs are preferably entered into the dosing device 1 via the data input device 28 and stored in their memory 29. The input and the choice of the wash program can be made interactively via the display 30. The metering device communicates with the dishwasher 2 via data lines, not shown here, and thereby receives the signals necessary for controlling the metering pumps 25. The main signals are provided for pre-dosing, main dosing and final rinsing.

The control or regulating device 27 may be designed as a pure control, wherein the pre-entered and currently selected wash program is played by the exact time depending on the individual components Program progress are added. Alternatively, however, the control or regulating device 27 may also be designed as a control by measuring, as shown here, via a measuring device 26, a controlled by the rinsing controlled variable. In the preferred embodiment, the measuring device 26 is designed as a conductivity measuring probe and arranged in the main washing tank. The measured value of the controlled variable, preferably the electrical conductivity of the rinsing liquor, in this embodiment variant is preferably compared permanently with the desired value specified in the rinsing program. If the controlled variable deviates from the nominal value, a corresponding addition of the required component of the dishwashing detergent takes place. In this case, it can be provided both that the components are added individually and independently of one another. Alternatively, however, it can also be provided that one component, for example the alkaline component, acts as a conductive component and the other components are added thereto in a quantitative ratio determined in advance in the rinsing program. Both control and regulation can be adapted to daytime demand fluctuations.

As a rule, at least once a day the entire rinsing liquor is emptied from the tanks 13 to 16 and replaced by fresh water. In this process, the metering device 1 starts the dosage of a preset amount of the alkaline component and, depending on the program, the corresponding composition of the complexing agents and dispersants. After heating, the washing process begins, whereby the items to be washed pass through the individual zones 3 to 7. During the washing process, the metering device measures by means of the measuring device 26, the controlled variable, preferably the conductivity of the wash liquor and dosed as described above, the individual components, so that the measured controlled variable is always adjusted to the desired value. If necessary, bleaching and / or disinfecting agents can be added to the rinsing liquor according to the same principle.

According to the guidelines for large kitchens, food with temperatures of at least 70 ° C must be served. The starch contained in the food, for example soups, accumulates at this temperature to the most preheated crockery and can often not be completely removed for economic reasons (too high a detergent dosage). Therefore, a basic cleaning with a separate product must be done regularly.

For this special rinsing programs with increased use of e.g. provided highly concentrated liquor, whereby the strength is removed again.

1. 1. Das zeitgesteuerte Abrufen der eingestellten Programme mit bis zu 20 Schaltpunkten pro Tag. Hierdurch kann das Auswechseln der Spülflotte hinausgezögert werden, indem nach einer gewissen Zeit ein anderes Spülprogramm aktiviert wird, wodurch die Dosierung der Dispergiermittel erhöht werden kann. Hierdurch können Kosten für Wasser, Strom, Kanal und die Stammdosierung notwendige Chemie eingespart werden.
2. 2. Die Möglichkeit zur manuellen Programmauswahl mit Unterbrechung der Schaltuhren.
3. 3. Das Auslösen eines Alarms bei leeren Vorratsbehältern 19 bis 23 und das Stoppen der Dosierung.
4. 4. Überwachung der Waschtank- und Nachspültemperatur mit Auslösung eines Alarms bei Unter- oder Überschreitung der vorab einstellbaren Grenzwerte (Hilfe für die Einhaltung von HACCP-Richtlinien).
5. 5. Aufzeichnung von Fehlern mit Datum, Uhrzeit und Programmnummer.
6. 6. Möglichkeit zur maschinellen Grundreinigung von Geschirr ohne zusätzlichem Aufwand und ohne zusätzliche Spezialprodukte.

Further preferred features of the metering device 1 according to the invention are:

1. 1. The timed retrieval of the set programs with up to 20 switching points per day. As a result, the replacement of the rinsing liquor can be delayed by activating another rinse program after a certain time, whereby the dosage of the dispersants can be increased. As a result, costs for water, electricity, channel and the master dosing necessary chemistry can be saved.
2. 2. The possibility of manual program selection with interruption of the timers.
3. 3. The triggering of an alarm when empty storage containers 19 to 23 and stopping the dosage.
4. 4. Monitoring of the wash tank and rinse temperature with triggering of an alarm if the preset limits are exceeded or not exceeded (HACCP guidelines help).
5. 5. Recording of errors with date, time and program number.
6. 6. Possibility of machine basic cleaning of dishes without additional effort and without additional special products.

In general, therefore, an individual solution adapted to the respective task of a dishwasher can be realized with the inventive dosing device 1 shown schematically in the figure, since the individual respectively currently required substances or components of the dishwashing detergent on site, at the right time and in the right amount in the dishwasher 2 are dosed. The invention is not limited to the embodiment shown here. Thus, the metering device according to the invention can be realized, for example, as a programmable logic controller (PLC) or as a metering computer.

In addition, the metering device 1 can also be equipped with a suitable, preferably bidirectional, interface for data transmission from and to an external data processing device (for example a laptop). Via the interface, then e.g. both rinse programs on the metering device 1 and / or log files on program flow, errors or the like are transmitted to the external data processing device. It can also be provided that additional components of the Geschirreinigungsmittels be dosed by the metering device according to the invention in the main tank but also in other tanks. In addition, there are also numerous modifications with respect to the control variable determining measuring devices. Thus, it can also be provided to determine different control variables, which are preferably characteristic of individual components of the dishwashing detergent, using different measuring devices 26.

As suitable alkaline component, dispersant, complexing agent, bleach and / or disinfectant and rinse aid, various known in the prior art substances can be used. Among others, substances having the following characteristics are possible:

The alkaline component is preferably provided to have at least one corrosion inhibitor, preferably at least one silicate, and at least 30% potassium hydroxide. As a complexing agent, it is preferable to use a substance having more than 30% of sodium nitriloacetate and less than 5% of phosphonates. With the dispersant, it is advantageous if this contains 5 to 15% of phosphonates and / or polycarboxylates. The bleach and / or disinfectant preferably contains 35% hydrogen peroxide and / or sodium hypochlorite solution with 15% active chlorine. The rinse aid can be provided to contain more than 5% and less than 15% of nonionic surfactants and / or preservatives and / or solubilizers and / or dyes.

Claims (29)

1. A metering device for metering a dishwashing agent comprising at least two components into a dishwashing machine, in particular a transport machine or belt machine, wherein the dishwashing agent has at least one alkaline component and at least one dispersing agent and possibly at least one complexing agent, characterised in that the metering device (1) has at least two mutually separate inlets (24) for at least one respective component of the dishwashing agent and a control or regulating device (27), wherein the control or regulating device (27) meters the individual component into the dishwashing machine (2) in a preferably previously and/or variably adjustable quantitative ratio relative to each other.
2. A metering device according to claim 1 wherein the dishwashing machine has a main washing zone with a main washing tank, characterised in that the metering device (1) meters the components of the dishwashing agent, preferably the alkaline component and the dispersing agent, into the main washing zone (4), preferably into the main washing tank (14).
3. A metering device according to one of claims 1 or claim 2 characterised in that the metering device (1) includes a memory (29) and a data input device (28), preferably a keyboard, wherein at least one and preferably various quantitative ratio or ratios of the individual components of the dishwashing agent can be inputted as part of at least one washing program, preferably various washing programs, into the memory (29) by way of the data input device (28) and can be stored therein, wherein the control or regulating device (27) meters the individual components of the dishwashing agent, preferably the alkaline component and the dispersing agent, in dependence on the quantitative ratio or ratios stored in the washing program (programs).
4. A metering device according to claim 3 characterised in that the quantitative ratio or ratios can be inputted into the washing program or programs variably in dependence on the time of day and can be stored in said program or programs.
5. A metering device according to claim 3 or claim 4 characterised in that the washing program can be interrupted and at least one predeterminable special washing program can be performed during the interruption in the washing program.
6. A metering device having at least one measuring device for determining at least one regulating parameter according to one of claims 1 to 5 characterised in that the control or regulating device (27) aligns the measured regulating parameter with a predeterminable, preferably variable-time reference value, possibly continuously, by metering at least one component of the dishwashing agent, preferably the alkaline component or the dispersing agent.
7. A metering device according to claim 6 characterised in that the control or regulating device (27), from a comparison of the measured regulating parameter with the reference value, determines the amount to be metered of a first component of the dishwashing agent, preferably the alkaline component, and therefrom by way of a predeterminable quantitative ratio, the amounts to be metered of the other components of the dishwashing agent.
8. A metering device according to claim 6 or claim 7 characterised in that the measuring device (26) has an electrical conductivity probe and the regulating parameter is the electrical conductivity of a washing water composition or a washing solution.
9. A metering device according to one of claims 1 to 8 characterised in that the metering device (1) additionally also meters at least one bleaching agent and/or disinfectant and/or at least one rinsing agent together or at spatially separate locations from the dishwashing agent into the dishwashing machine (2).
10. A metering device according to one of claims 1 to 9 characterised in that the alkaline component has at least one corrosion inhibitor, preferably at least one silicate, and at least 30% of potassium hydroxide.
11. A metering device according to one of claims 1 to 10 characterised in that the dispersing agent has 5 to 15% of phosphonates and/or polycarboxylates.
12. A metering device according to one of claims 1 to 11 characterised in that the complexing agent has at least 30% of sodium nitritoacetate and less than 5% of phosphonates.
13. A metering device according to claim 9 characterised in that the bleaching agent and/or disinfectant has 35% of hydrogen peroxide and/or sodium hypochlorite solution with 15% of active chlorine.
14. A metering device according to one of claims 9 to 13 characterised in that the rinsing agent has more than 5% and less than 15% of non-ioniv surfactants and/or preserving agents and/or solubilising agents and/or dyes.
15. A metering device according to one of claims 1 to 14 characterised in that at least temporarily during operation of the metering device at least one inlet (24) has the alkaline component flowing therethrough and at least one other inlet (24) has the dispersing agent flowing therethrough and optionally further inlets (24) have the complexing agent or other components of the dishwashing agent flowing therethrough, and the control or regulating device (27) meters at least the alkaline component and the dispersing agent and possibly the complexing agent and/or other components of the dishwashing agent in a preferably previously and/or variably adjustable quantitative ratio.
16. A method of metering a dishwashing agent comprising at least two components into a dishwashing machine, in particular a transport machine or belt machine, by means of a metering device according to claim 1, wherein the dishwashing agent has at least one alkaline component and at least one dispersing agent and possibly at least one complexing agent, characterised in that the alkaline component and the dispersing agent and possibly the vomplexing agent and/or other components of the dishwashing agent are metered independently of each other by the metering device.
17. A method according to claim 16 wherein the dishwashing machine has a main washing zone with a main washing tank, characterised in that the components of the dishwashing agent, preferably at least the alkaline component and the dispersing agent are metered by the metering device (1) into the main washing zone (4), preferably into the main washing tank (14).
18. A method according to one of claims 16 or claim 17 characterised in that the metering device (1) includes a memory (29) and a data input device (28), preferably a keyboard, wherein at least one and preferably various quantitative ratio or ratios of the individual components of the dishwashing agent can be inputted as part of at least one washing program, preferably various washing programs, into the memory (29) by way of the data input device (28) and can be stored therein, wherein the individual components of the dishwashing agent, preferably the alkaline component and the dispersing agent are metered by the control or regulating device (27) in dependence on the quantitative ratio or ratios stored in the washing program (programs).
19. A method according to claim 18 characterised in that the quantitative ratio or ratios can be inputted into the washing program or programs variably in dependence on the time of day and can be stored in said program or programs.
20. A method according to claim 18 or claim 19 characterised in that the washing program can be interrupted and at least one predeterminable special washing program can be performed during the interruption in the washing program.
21. A method having at least one measuring device for determining at least one regulating parameter according to one of claims 16 to 20 characterised in that the measured regulating parameter is aligned with a predeterminable, preferably variable-time reference value, possibly continuously, by metering at least one component of the dishwashing agent, preferably the alkaline component or the dispersing agent.
22. A method according to claim 21 characterised in that the amount to be metered of a first component of the dishwashing agent, preferably the alkaline component, and therefrom by way of a predeterminable quantitative ratio, the amounts to be metered of the other components of the dishwashing agent are determined from a comparison of the measured regulating parameter with the reference value.
23. A method according to claim 21 or claim 22 characterised in that the measuring device (26) has an electrical conductivity probe and the regulating parameter is the electrical conductivity of a washing water composition or a washing solution.
24. A method according to one of claims 16 to 23 characterised in that additionally also at least one bleaching agent and/or disinfectant and/or at least one rinsing agent are metered together or at spatially separate locations from the dishwashing agent by the metering device (1) into the dishwashing machine (2).
25. A method according to one of claims 16 to 24 characterised in that the alkaline component has at least one corrosion inhibitor, preferably at least one silicate, and at least 30% of potassium hydroxide.
26. A method according to one of claims 16 to 25 characterised in that the dispersing agent has 5 to 15% of phosphonates and/or polycarboxylates.
27. A method according to one of claims 16 to 26 characterised in that the complexing agent has at least 30% of sodium nitriloacetate and less than 5% of phosphonates.
28. A method according to claim 24 characterised in that the bleaching agent and/or disinfectant has 35% of hydrogen peroxide and/or sodium hypochlorite solution with 15% of active chlorine,
29. A method according to one of claims 24 to 28 characterised in that the rinsing agent has more than 5% and less than 15% of non-ionic surfactants and/or preserving agents and/or solubilising agents and/or dyes.

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