WO2010142564A1 - Dishwasher having a water softening unit and corresponding maintenance method - Google Patents

Abstract

The invention relates to a dishwasher, especially a domestic dishwasher (1), comprising a water inlet device (5) for the inlet of water, a water softening unit (14, 15, 20) which can be supplied by the water inlet device (5) and which has an ion exchanger (14) for softening and/or demineralizing the water and a maintenance unit (15, 20) for maintaining the ion exchanger (14), and a program control device (19) in which at least one wash program (SP) for controlling a wash cycle for cleaning dishes is stored. The water inlet device (5) has a hot water inlet (6, 7) and a cold water inlet (8, 9), the hot water inlet (6, 7) being adapted to receive hot water from an external hot water supply (WH) and the cold water inlet (8, 9) being adapted to receive cold water from an external cold water supply (KH). The respective selected wash program (SP) has at least one program step (VS, RS, ZS, KS) for washing dishes using hot water from the hot water supply (WH), at least one program step (RES, DS) for maintaining the ion exchanger (14) by means of the maintenance unit (15, 20), using cold water from the cold water supply (K), being activated upon completion or after completion of the selected wash program (SP) if the program control device (19) requests maintenance of the ion exchanger (14).

Description

 Dishwasher with a softening device and associated maintenance process

The present invention relates to a dishwasher, in particular a domestic dishwasher, having a water inlet device for receiving water, with a water softener chargeable by the water inlet device, which has an ion exchanger for softening and / or desalting of water and a maintenance device for waiting for the ion exchanger, and with a flow control device in which at least one wash program for controlling a wash cycle for cleaning items to be washed is stored.

In modern dishwashers, dishes to be rinsed are usually introduced into a rinsing container and there cleaned in a rinsing process, which is also called rinse, with the aid of water and then dried. The aim is to perform a rinse so that a predefined cleaning result and a predefined drying result is achieved as efficiently as possible. Demanded is a high overall efficiency, which results from the cleaning efficiency and the drying efficiency. The cleaning efficiency corresponds in particular to the ratio of the cleaning result achieved by means of a rinse cycle and the effort required for this purpose, wherein the effort can comprise several dimensions, for example the energy requirement, the water requirement and / or the time requirement. Furthermore, the drying efficiency corresponds in particular to the ratio of the drying result achieved by means of a rinse cycle and the effort required for this purpose, wherein the effort here can also include several dimensions, for example the energy requirement and / or the time required.

In modern dishwashers, as a rule, a sequence control device is provided which automatically controls a rinse cycle according to a usually selectable rinse program. The water required for carrying out rinses can be taken up in known dishwashers via a water inlet device, which can receive water, for example, from a water supply installed on the building side. A washing program usually has several successive program steps for the treatment of the items to be washed, wherein the water is provided in the water-conducting program steps depending on the respective program step with cleaning and / or additives and brought to a favorable temperature for the respective program step. In order to be able to provide the water intended for rinsing with the intended cleaning and / or additives, modern dishwashers usually have automatic dosing devices. Furthermore, dishwashers can usually have an electric heater to bring the water intended for rinsing to the required temperatures.

In order to clean the items to be washed in this time sequence, a typical washing program comprises a pre-rinsing step, a cleaning step, an intermediate rinsing step and a rinsing step in which the items to be washed are each subjected to water. Furthermore, a typical washing program includes a subsequent drying step for drying the cleaned dishes. However, it is also possible to provide rinsing programs in which one or more of these steps are hidden or missing. Also, rinse programs are possible in which one or more of these steps are repeated several times.

As is known, a high lime content and / or magnesium content of the water provided in the dishwasher for supplying items to be washed is disadvantageous for the dishwashing result, since the limescale settles on the items to be washed and can therefore cause unwanted clouding, especially in the case of glassware. In dishwashers, therefore, the water taken up with the water inlet device is first passed over a softening device for softening or decarbonating water before it is used for a rinsing or rinsing process. As a rule, the softening device comprises an ion exchanger for softening and / or desalting water and a maintenance device for servicing the ion exchanger.

The ion exchanger contains a resin with the property of sorbing the calcium ions or magnesium ions dissolved in the water, whereby the lime content of the Water is reduced. In order to relieve the resin of the ion exchanger of the sorbed lime, a maintenance device is provided, which is designed for automatic maintenance of the ion exchanger.

The maintenance of the ion exchanger usually comprises a regeneration step and a purging step. During the regeneration step, a regenerating brine, previously prepared from water and regenerating salt, from the regenerating brine device is supplied to the ion exchanger for the servicing device, which essentially contains sodium chloride in aqueous solution. As soon as this regenerating brine comes into contact with the resin of the ion exchanger, the sodium ions contained in the regenerating brine (left out of the regenerating brine means) are sorbed by the resin instead of the calcium ions or magnesium ions, while the calcium ions or magnesium ions from the resin are mixed with the regenerating salt Brine go into solution.

The regenerating brine is usually prepared in a Regeneriersoleeinrichtung the maintenance facility and kept ready until the beginning of the regeneration step. From the Regeneriersoleeinrichtung the regenerating brine is then passed at the beginning of the regeneration step in the ion exchanger. After expiration of a time required for the regeneration of the ion exchanger, the ion exchanger is flushed through with water absorbed by the water inlet device in a rinsing step, so as to dissipate the regenerating brine from the ion exchanger, so that the ion exchanger is again available for water softening available.

Against the background of increased energy and water costs, but also against the background of a generally increased environmental awareness as well as changed living habits of further parts of the population, a need has developed for even more efficient household dishwashers.

A disadvantage of the known dishwasher equipped with a softening device is that it no longer meets the current need for efficiency. The object of the present invention is to provide a dishwashing machine equipped with a softening device, in particular a household dishwasher, which enables more efficient rinsing operations.

The object is achieved in a dishwasher of the type mentioned above in that the water inlet device has a hot water inlet and a cold water inlet, the hot water inlet for receiving hot water from an external hot water supply and the cold water inlet are provided for receiving cold water from an external cold water supply, said the each selected wash program has at least one program step for washing items using hot water from the hot water supply, and wherein at least one program step for waiting the ion exchanger by means of the maintenance device using cold water from the cold water supply is provided at the expiration or after the expiry of this selected wash program, if maintenance of the ion exchanger is requested by the process control device.

Dishwashers and in particular household dishwashers are usually operated in locations where a hot water supply and a cold water supply are available. The temperature of the hot water typical fixed hot water supplies can for example be in a range of about 40 ⁰ C to 70 ⁰ C. By contrast, the temperature of the cold water of typical fixed cold water supplies is in a range of about 5 ° C to 15 ° C.

A water inlet device, which has a hot water inlet and a cold water inlet, that is equipped with a bithermic water connection, makes it possible to perform a rinse cycle for cleaning and / or drying of dishes in a more efficient manner. Thus, now rinsing programs for controlling a rinse are possible, which provide the implementation of individual program steps using hot water from an external hot water supply and the implementation of other program steps using cold water from an external cold water supply. That way, both compared to known dishwashers, which are provided - as usual especially in Europe - exclusively for connection to a cold water supply, as well as to known dishwashers, which are - as usual especially in North America - exclusively for connection to a hot water supply, a significant increase in efficiency be achieved.

If a program step by its nature requires or at least makes desirable the use of water at a high temperature, hot water can be taken from the external water supply for this program step. The hot water can be taken before or during the respective program step.

Taking hot water for such a program step is in many cases more energy and cost efficient than taking cold water. The reason for the increased cost efficiency is that when receiving hot water, the internal electrical energy consumption of the dishwasher for a rinse by a reduced electrical energy consumption for heating the absorbed water drops significantly. This can lead to a significant reduction in household electricity costs. This saving is greater in many cases, as the additional cost of generating the hot water of the external hot water supply. In this way, an increase in efficiency compared to a dishwasher can be achieved, which is provided exclusively for connection to a cold water supply.

This is especially true when the household a modern condensing heating system such. a pellet furnace plant or a Holzscheitofenanlage, a combined heat and power plant, district heating system or local heating system is available, which is coupled to the hot water supply system. However, the cost advantage can be further increased if the household has a geothermal heat pump or a solar system for generating hot water.

Furthermore, for a program step in which the use of high-temperature water brings no advantages or disadvantages, cold water can the external cold water supply. Again, the recording of the cold water before or during the respective program step can be done.

Unlike a dishwasher, which is intended exclusively for connection to a hot water supply, so spültechnologische disadvantages can be avoided, which could occur by a forced use of hot water in specific program steps. In addition, the partial intake of cold water from the external cold water supply, the amount of hot water, which must be removed from the external hot water supply for a rinse, without disadvantages with respect to the cleaning effect and / or the drying effect can be minimized. In this way it is ensured that the saving of electrical energy for the operation of an electric heater of the dishwasher and the additional effort to provide a sufficient amount of hot water by means of the external hot water supply are in a favorable ratio.

The dishwasher according to the invention realizes the advantages mentioned in that at least one washing program is stored in the process control device, which provides at least one program step for washing items using hot water from the hot water supply and at least one program step to maintain the ion exchanger using cold water from the cold water supply ,

In a program step for rinsing items to be washed, the achievable cleaning effect depends on the temperature of the water used for rinsing. Therefore, in many cases it is desirable or even necessary to use water which has a higher temperature than water of a conventional cold water supply. Therefore, the use of hot water in such a program step, a significant amount of energy can be saved, which would have to be expended when using cold water to its heating. On the other hand, for the maintenance of an ion exchanger in many cases water can be used without problems whose temperature corresponds to the temperature of the cold water of a cold water supply. Therefore, by the maintenance of the ion exchanger by means of cold water from the cold water supply compared to conventional dishwashers in which maintenance of the ion exchanger is done with hot water, a lower, in particular thermal load of the external hot water supply can be achieved without the need for additional energy elsewhere. In this way, there is an increase in the overall efficiency of a rinse carried out by means of a dishwasher according to the invention.

According to an expedient development of the invention, the rinsing program can provide a regeneration step for the maintenance of the ion exchanger, in which the ion exchanger is exposed to a regenerating brine which is prepared using cold water from the cold water supply and regenerating agent from the maintenance device. In the production of a regenerating brine, a defined amount of water taken up from an external water supply is usually passed into a regenerating brine device, which is provided for the preparation and optionally for the storage of a regenerating brine. The Regeneriersoleeinrichtung is preferably part of the maintenance facility. It contains a regenerating agent, for example a regenerating salt, which can be refilled by a user. With a sufficient residence time of the water, the regenerant dissolves in it to the saturation limit. Although the solution process can be accelerated by a higher temperature of the water used for this purpose, but this would bring no significant advantage. As a rule, there is sufficient time between two regeneration steps to form the regenerating brine when cold water is used. Furthermore, the ion exchange processes provided during the regeneration of the ion exchanger do not require a higher temperature of the regenerating brine. Therefore, cold water from the cold water supply can be easily used to prepare the regenerating brine so as to reduce the demand for hot water from the hot water supply without causing a deterioration of the maintenance result. According to a preferred embodiment of the invention can be provided that the regeneration step comprises a substep in which the Regeneriersoleeinrichtung the maintenance device cold water is supplied from the cold water supply, so as to press Regeneriersole from the Regeneriersoleeinrichtung in the ion exchanger. Usually, in an initial substep of the regeneration step, the ion exchanger is charged with regenerating brine from the regenerating brine means by forcing regenerating brine kept ready in the regenerating brine means by feeding further water to the regenerating means from the regenerating means into the ion exchanger. As water, which presses the regenerating brine from the regenerating device, also water with low temperature, ie cold water can also be used without problems. Thus, the use of cold water from the cold water supply in the sub-step for pressing the regenerating brine in the ion exchanger to a further saving of hot water from the hot water supply, without this would create other problems.

According to an expedient development of the invention, the rinsing program provides a rinsing step for servicing the ion exchanger, in which the ion exchanger is rinsed with cold water from the cold water supply, so as to rinse Regeneriersole from the ion exchanger. At the end of the maintenance of the ion exchanger, a flushing step is usually provided in which the ion exchanger is flushed through with water taken up by the water feed device so as to remove the regenerating brine. Again, the use of cold water from the cold water supply leads to a further saving of hot water from the hot water supply, which further improves the efficiency.

According to a preferred embodiment of the invention, the wash program provides a cleaning step for washing items to be washed, in which a loading of items to be washed with hot water from the hot water supply. A cleaning step is used to thoroughly clean the dishes. For this purpose, it is necessary to apply water to the wash ware, which has a comparatively high temperature in order to achieve a high thermal cleaning effect. In addition, water is generally added to the detergent whose chemical cleaning action is best at a higher temperature. Usually is Therefore, a temperature of about 50 ⁰ C to 70 ⁰ C provided for a cleaning step. When using hot water from the hot water supply for the cleaning step so it is ensured that the heat energy withdrawn from the hot water supply is used meaningfully. In this case, a high saving of electrical energy can be achieved here, since the hot water from the hot water supply in many cases not at all, in other cases only to a small extent, must be reheated by the electric heater of the dishwasher to the required minimum temperature or effective temperature to reach.

According to an advantageous embodiment of the invention, the rinse program provides a rinse step for rinsing items to be washed, in which a loading of items to be washed with hot water from the hot water supply. A rinse step serves in particular to avoid stains on the dishes, which could be caused by dissolved substances in the water, such as salt and / or lime. For this purpose, the water is added during the rinse step with rinse aid. Another object of the rinse step is to prepare a subsequent drying step. Thus, the dishes are heated by hot water in particular, having for example a temperature of about 60 ⁰ C to 75 ° C, is used during the rinsing step. In the final drying step, water droplets adhering to the hot dishes evaporate and settle on the inside of the washing container due to the lower temperature prevailing there. When using hot water from the hot water supply for the rinse step so also ensures that the heat energy withdrawn from the hot water supply is used meaningfully. Again, a high saving in electrical energy can be achieved because the hot water from the hot water supply in many cases not, in other cases only to a small extent, must be reheated by the electric heater of the dishwasher to the required for the final rinse step temperature to reach.

According to a preferred development of the invention, the rinsing program provides for a pre-rinsing step, in particular before the cleaning step is carried out, for rinsing items to be washed, in which a Loading of items to be washed with cold water from the cold water supply. The pre-rinse step serves to remove coarse contaminants from the dishes to prepare for the cleaning step. In principle, no higher temperatures are required for this purpose. However, the removal of the coarser dirt by higher temperatures during the pre-rinse step can be accelerated in many cases. Thus, the required cleaning effect of the pre-rinse step can be achieved in a shorter time. In this case, the use of hot water from the external hot water supply, the electrical energy consumption of the dishwasher can be further reduced.

According to an advantageous development of the invention, the rinsing program optionally provides an intermediate rinsing step, in particular after the cleaning step, for rinsing items to be washed, in which removal of detergent from the items to be washed after the cleaning step is followed by loading of items with cold water from the cold water supply. An intermediate rinsing step serves in particular for the removal of detergent residues which adhere to the items to be washed after a cleaning step. Again, the desired effect of the intermediate rinse step can be achieved in a shorter time if water with a higher temperature is used. By using hot water from the external hot water supply, the electrical energy demand of the dishwasher can be further reduced.

According to a preferred embodiment of the invention can be provided that the hot water supply includes a hot water valve and the cold water inlet a cold water valve, the hot water valve and the cold water valve are independently controllable by the flow control device. This makes it possible in a simple manner to carry out the intended by the wash program recording hot water from the hot water supply and provided by the wash program recording of cold water from the cold water supply. In particular, can be dispensed with an external device for controlling the water absorption.

According to an expedient development of the invention, it can be provided that the hot water valve is connected to an upstream end of a hot water valve. arranged hose and is adapted to be attached to a fitting of the external hot water supply, and / or that the cold water valve is disposed at an upstream end of a cold water hose and adapted to be attached to a fitting of the external cold water supply. For this purpose, the hot water valve and / or the cold water valve can have, for example, connection threads which correspond to threads of domestic taps. Such valves can be designed in particular as Aquastop valves.

The arrangement of the hot water valve and / or the cold water valve at the upstream end of the bithermic water inlet device has the advantage that practically no leakage water can escape from the dishwasher, even in the event of damage, as long as the valves are closed. If the valves are designed to close when not energized, leaking of leakage water from a switched-off dishwasher is prevented in virtually all cases. In order to prevent leakage of leakage water from a switched-on dishwasher, the flow control device, a leak water sensor for detecting leak water, especially below the bottom assembly of the dishwasher, be assigned, so that the flow control device can close the valves when leakage water occurs during operation of the dishwasher ,

According to a preferred embodiment of the invention it is provided that a downstream end of the hot water hose and a downstream end of the cold water hose via a connecting piece, in particular Y-connection piece, liquid-conducting, in particular with the aid of a supply hose is connected to a housing-fixed connection piece of the dishwasher. Such a design of the water inlet device is structurally simple and shortens the total hose length required in many cases, especially if the connection points of the external hot water supply and the external cold water supply are further removed from the installation of the dishwasher, as in this case two longer parallel tubes behind the Connector can be dispensed with. The invention also relates to a method for servicing the ion exchanger of a dishwasher, in particular a domestic dishwasher, having a water inlet device for receiving water, with a water softening device that can be charged by the water inlet device, which contains an ion exchanger for softening and / or desalting water and a maintenance device for servicing the ion exchanger comprising, and with a flow control device for controlling the rinse cycle of at least one wash program for cleaning items to be washed, which is characterized in that the water inlet device with its hot water inlet for receiving hot water from an external hot water supply and with their cold water inlet for receiving from each selected wash program of the flow control is controlled by cold water from an external cold water supply such that the selected wash program at least one program step for washing dishes r use of hot water from the hot water supply and at the expiration or after the expiration of this selected wash program at least one program step to wait for the ion exchanger is performed by means of the maintenance device using cold water from the cold water supply, if a maintenance of the ion exchanger is requested by the flow control device.

Other developments of the invention are given in the dependent claims.

The invention and its developments and advantages thereof are explained in more detail with reference to drawings. Show it:

Figure 1 is a schematic spatial representation of an advantageous embodiment of a dishwasher according to the invention;

FIG. 2 is a schematic block diagram of the dishwasher of FIG

FIG. 1; and

FIG. 3 shows a schematic functional diagram for explaining the function of the dishwasher of FIG. 1. In the following figures, corresponding parts are provided with the same reference numerals. Only those components of a dishwasher are provided with reference numerals and explained, which are required for the understanding of the invention and its advantageous developments. It goes without saying that the dishwasher according to the invention can comprise further parts and assemblies.

1 shows a schematic spatial representation of an embodiment of a dishwasher 1 according to the invention. This has a washing container 2, which can be closed by a door 3, so that a washing cell for washing dishes is formed. The rinsing container 2 is arranged in the interior of a housing 4 of the dishwasher 1, which may have standard dimensions. For example, the housing 4 may have a width of 45 cm or 60 cm, which enables integration of the dishwasher 1 into a standard kitchen unit with a corresponding installation niche. Possibly. the outer housing, in particular in the region of the side walls, the top wall, and / or rear wall of the washing compartment of the dishwasher 1 can be partially or completely omitted. This is particularly useful in fully integrated dishwashers, which are installed in the Einbaunische a kitchenette.

On the back of the dishwasher 1, a schematically illustrated water inlet device 5 is arranged. This has a hot water inlet 6, 7 and a cold water inlet 8, 9, wherein the hot water inlet 6, 7 for receiving hot water from an external hot water supply WH and the cold water inlet 8, 9 is provided for receiving cold water from an external cold water supply KH.

Here, the hot water inlet 6, 7 comprises a controllable hot water valve 6 and the cold water inlet 8, 9 a controllable cold water valve 8. The hot water valve 6 and cold water valve 8 are basically constructed identically. For example, both valves 6, 8 may each be designed as a solenoid valve. The inlet sides of the valves 6, 8 are each designed so that they to fittings WA, KA a household hot water supply WH and cold water supply KH, for example, at the taps, can be attached. The connection can be made in each case by means of a screw connection, a snap connection or the like. Such valves 6, 8 are also known under the name Aquastop valve 6, 8. Advantageously, these are closed when they are not activated, so that the dishwasher 1 is disconnected from the water supply in the off state. In this way, leakage of leakage water from the switched-off dishwasher 1 can be avoided in the event of a fault.

1, the inlet side of the hot water valve 6 is connected to a hot water tap of the hot water supply WH and the input side of the cold water valve 8 to a cold water tap of the cold water supply KH. The outlet side of the hot water valve 6 is connected to a hot water hose 7 and the outlet side of the cold water valve 8 with a cold water hose 9, the downstream ends of the hot water hose 7 and the cold water hose 9 are connected to an input side of a connector 10, in particular Y-connector , At its output side, a common inlet hose 1 1 connects for hot water and cold water, which in turn is connected to a connector 12 on the housing 4 of the dishwasher 1. By means of the water inlet device 5, it is consequently possible to individually direct hot water from an external hot water supply WH and / or cold water from an external cold water supply KH into the interior of the dishwasher 1.

The hot water hose 7, the cold water hose 9 and / or the common inlet hose 1 1 may be formed as safety hoses with an inner water-carrying pressure hose and an outer Hüllschlauch, wherein between the pressure hose and Hüllschlauch each a leakage water channel can be provided for discharging any leak water occurring. In this case, the connecting piece 10 may be formed such that the leakage water passages of the hot water hose 7, the cold water hose 9 and the common inlet hose 11 are connected to one another, so that leakage water, which occurs during operation of the dishwasher 1 in the region of the water inlet device 5, via the housing-fixed connection piece 12 into the interior of the dish- Dishwasher 1 is passed. Here it can be detected by a leak water sensor, not shown, so that appropriate measures, such as closing the hot water valve 6 and cold water valve 8, can be initiated.

As an alternative to this external arrangement of, in particular Y-branch, connector 10 outside the dishwasher, it may be advantageous if the connector on the device side, in particular device internally, on the device side connector, in particular without external inlet hose, fixedly coupled or at this with is formed. This can in particular already be prepared from the outset from the factory. In this optional embodiment, the common inlet hose can possibly be saved. In particular, the connecting piece 12 may be provided together with the connecting piece in the region of the base assembly on or in this.

Downstream of the housing-fixed connector 12, a free flow path 13 is provided. In the free flow path 13 is a so-called pipe interruption, which serves to prevent a sucking back of water from the dishwasher 1, if in the external water supply by dynamic processes, a negative pressure. This prevents in particular that already used water, which may be mixed with dirt, cleaning agents and / or cleaning agents, gets back into the building water supply.

The dishwasher 1 has a softening device for softening or decarbonating water, which is provided for a rinsing or rinsing process. The softening device 14, 15 comprises an ion exchanger 14 for softening and / or desalting water and a maintenance device 15 for servicing the ion exchanger 14. The maintenance device 15 has a Regeneriersoleeinrichtung 15, which with an accessible from the interior of the washing compartment 2 and closable opening to Filling a regenerating agent is equipped.

The dishwasher 1 also has components not shown in FIG. 1, which make it possible to supply hot water and / or cold water from the outlet free flow path 13 in the ion exchanger 14 and / or in the Regeneriersoleeinrichtung 15 to lead.

In a lower region of the washing container 2, a pump pot 16 is provided, in which a circulating pump is suitably provided for circulating water in the washing container 2 during a rinse cycle. In this case, the circulation pump may have a heating device for heating the water located in the washing container 2, for example a water heater. Likewise, in the sump 16, a pump for pumping out water, for example at the end of a rinse cycle, be provided. However, the various pumping functions can also be perceived by a single pump in conjunction with switchable valves. The sump 16 is usually connected to a waste water connection piece 17 via means not shown so that water from the washing compartment 2 via a connected to the wastewater connection piece 17 sewage hose 18 in a building side installed wastewater A, such as a sewer pipe A, can be pumped.

The dishwasher 1 also has a flow control device 19 for controlling the course of a washing program. In the sequence control device 19, various rinse programs can be stored, which can be selected by an operator. The flow control device 19 is arranged inside the door 3 of the washing container 2, but could also be arranged elsewhere in the dishwasher 1.

Figure 2 shows a functional diagram of the dishwasher of Figure 1. The hot water valve 6 and the cold water valve 8 are each connected to the flow control device 19, in particular via associated electrical signal or data lines DL that both valves 6, 8 individually, ie are specifically controlled. This makes it possible to feed the washing container 2 of the dishwasher 1 via the connecting piece 10, the free flow path 13, a water distributor 20, the ion exchanger 14 and a drain 21 specifically with hot water and / or cold water. In the sump 16 of the washing container 2, a heating pump equipped with a circulation pump 22 is arranged, which is in communication with a arranged in the interior of the washing container 2 spray system 23. This makes it possible to apply in the washing container 2 arranged items to be washed during a wash with water to clean this. Furthermore, a drain pump 24 is arranged in the sump, which makes it possible to pump out water no longer needed to the outside via a wastewater connection piece 17. In the circulation pump 22, both the heating function and the pumping function can be individually controlled by the sequence control device 19. Furthermore, the flow control device 19 is also connected to the drain pump 24 for the control thereof.

The water distributor 20, which is part of the maintenance device 15, 20 for the maintenance of the ion exchanger 14, can be controlled by the sequence control device 19. The water distributor 20 can be a water distributor 20 which has an inlet and two outlets. It makes it possible for hot water and / or cold water flowing in through the free flow path 13 to be fed to both the ion exchanger 14 and the regenerating brine device 15 via corresponding liquid lines or channels.

The water diverter 20 has a first switching state designated "A", in which the water flowing to it is conducted via a liquid connection line L to the ion exchanger 14. The switching state "A" is assumed inter alia when water is supplied to the rinsing container 2, which is provided for applying wash ware. As a result, the water is softened by the ion exchanger 14 and / or desalted before it comes into contact with the dishes.

Furthermore, the water diverter 20 has a second switching state designated "B", in which the water flowing to it is led to the regenerating brine device 15. Switching state "B" serves to supply water to the regenerating brine device 15 by a defined amount of regenerating brine from the regenerating brine device 15 to press out through a liquid connection line FL in the ion exchanger 14, so as to initiate a regeneration step. Regenerative agent RM, which is stored in the regenerating agent unit, forms tion 15, and the water supplied from the water divider gradually a further amount of regenerating brine, which can be used for later regeneration steps.

After a corresponding exposure time, the regenerating brine contained in the ion exchanger 14 is flushed out of it by bringing the water splitter 20 into the switching state "A" and supplying it with water again they can be pumped out by means of the drain pump 24 to the outside.

The feeding of the dishwasher 1 with water is carried out as well as the control of the water switch 20, the heating pump 22 and the drain pump 24 and other not explained here devices of the dishwasher 1 in response to a wash program, which is stored in the flow control device 19. In the case of a dishwasher 1 according to the invention, at least one washing program is provided which can be selected specifically for efficient use of hot water from the hot water supply WH and cold water from the cold water supply KH.

Figure 3 shows a functional diagram for explaining the function and operation of the dishwasher 1 of Figures 1 and 2, which is designed according to an advantageous embodiment of the inventive design principle and the regeneration process according to the invention operates. For this purpose, the course of a wash program SP is shown, which is intended to control a sequence of a wash cycle so that an efficient use of hot water from the hot water supply WH and cold water from the cold water supply KH is ensured.

FIG. 3 shows, on a common time axis t, the curves SWV, SKV, BAP and SWA which indicate switching or operating states of components of the dishwasher 1 on the vertical axis Z.

The curve SWV represents the switching state of the hot water valve 6 of the dishwasher 1. Furthermore, the curve SKV shows the switching state of Cold water valve 8 of the dishwasher 1. The switching state "0" corresponds in each case to a closed valve 6, 8, the switching state "1" an open valve 6, 8. The curve BAP continues to represent the operating state of the sewage pump 24, wherein the off state by " 0 "and the on state are symbolized by" 1 ". Finally, the curve SWA shows the switching state of the water switch 20. Here, a first switching state, in which incoming water is passed to the ion exchanger 14, with "A" and a second switching state in which incoming water is passed to the Regeneriersoleeinrichtung 15, with "B" designated.

FIG. 3 shows, by way of example, a rinsing program SP, which in this chronological order comprises a pre-rinsing step VS, a cleaning step RS, an intermediate rinsing step ZS, a rinsing step KS and a drying step TS. In other examples, one or more of these steps might be hidden. Also examples would be possible in which one or more steps are repeated several times.

The first pre-rinsing step VS serves to remove coarse contaminants from the dishes so as to prepare the cleaning step RS. For this purpose, the hot water valve 6 is opened at the beginning of Vorspülschritts VS. The water switch 20 is in this case in the switching state "A", so that the supplied hot water passes through the ion exchanger 14 in the washing container 2. When the washing container 2 is charged with a sufficient amount for the pre-rinse step VS of softened hot water from the hot water supply WH The hot water valve 6 is closed again The softened hot water is circulated in the washing container 2 by means of the circulation pump 22 for a predetermined time, usually without - in the exceptional case with connection - their heating device, so as to pressurize the wash ware with hot water Hot water pumped by the drain pump 24 to the outside.

Alternatively, cold water from the cold water supply KH could be wholly or partially used during the pre-rinse step VS. This would lead to energy savings, but the pre-purging time would normally have to be extended in order to achieve a predetermined cleaning effect. The cleaning step RS performed after the pre-rinsing step VS serves to thoroughly clean the items to be washed. For this purpose, the hot water valve 6 is opened again at the beginning of the cleaning step RS. The water switch 20 is still in the switching state "A", so that the hot water supplied passes through the ion exchanger 14 in the washing container 2 until the washing container 2 is charged with a sufficient amount for the cleaning step RS amount of hot water from the hot water supply WH The hot water valve 6 is closed again when the washing container 2 is supplied with a sufficient amount of softened hot water from the hot water supply WH for the cleaning step RS The heating device of the circulating pump 22 can be switched on as required as a function of the temperature of the hot water supplied and as a function of the intended, desired rinsing temperature of the cleaning step RS now contaminated hot water pumped by means of the drain pump 24 via the waste water connection piece 17 from the washing tank 2 to the outside.

During the cleaning step RS, it is usually necessary to apply water to the wash ware, which has a comparatively high temperature in order to achieve a high thermal cleaning effect. In addition, water is generally added to the detergent whose chemical cleaning action is best at a higher temperature. Usually, therefore, a temperature of about 50 ⁰ C to 70 ⁰ C is provided for a cleaning step RS. When using hot water from the hot water supply WH for the cleaning step RS is thus ensured that the heat energy withdrawn from the hot water supply WH is used meaningfully. Here, a high saving in electrical energy can be achieved, since the hot water from the hot water supply WH in many cases not at all, in other cases only to a small extent, must be reheated by the electric heater of the circulation pump 22 of the dishwasher 1 to the to achieve the desired minimum temperature. In particular, during the cleaning step RS, the maintenance of the ion exchanger 14 is initiated from time to time as needed. After the washing container 2 is charged with a sufficient amount of hot water from the hot water supply WH for the cleaning step RS, a regeneration step RES is performed. For this purpose, the water switch 20 is brought into the switching state "B." The cold water valve 8 is then opened to charge the regenerating brine device 15 with cold water from the cold water supply KH, whereby regenerating brine from the regenerating brine device 15 is forced into the ion exchanger 14 via a liquid connection line VL When sufficient cold water has been introduced into the regenerating brine device 15, the cold water valve 8 is closed again and the water splitter 20 is returned to the switching state "A". The cold water introduced into the regeneration brine device 15 during the regeneration step RES remains there until a subsequent regeneration step and until then forms further regenerating brine by dissolution of the regenerating agent RM.

After the regeneration step RES, the ion exchanger 14 is cleaned of consumed regenerating brine in a time-sequential rinsing step DS. For this purpose, the cold water valve 8 is temporarily opened when the water switch 20 is in the switching state "A" so that cold water flows through the ion exchanger 14. The regenerating brine which reaches the washing container 2 is subsequently pumped out through the drain pump 24.

The duration of the regeneration step RES, during which regenerating brine is located in the ion exchanger 14, expediently ends at the same time as the purifying step RS. In this way it is prevented that regenerating brine introduced into the rinsing container during the rinsing step DS is circulated through the circulating pump 22 switched on during the rinsing step RS in the rinsing container 2, whereby contact between regenerating brine and items to be washed can be prevented. Because during the Durchspülschritts DS the circulation pump 22 is turned off. The now performed intermediate rinse step ZS for removing detergent from the items to be washed after the cleaning step RS also provides for a loading of the washing container 2 with hot water from the hot water supply WH, to be able to apply hot water to the ware can. For this purpose, first the hot water valve 6 is opened until the washing container 2 is charged with a sufficient amount of hot water for the intermediate rinse step ZS. This hot water is circulated by means of the circulation pump 22 for a predetermined time, which as a rule can be omitted a connection of the heater. Thereafter, the now contaminated cold water is pumped out by means of the drain pump 24 to the outside.

Alternatively, cold water from the cold water supply KH could be wholly or partially used during the intermediate rinse step ZS. This would lead to energy savings, but the pre-purging time would normally have to be extended in order to achieve a predetermined cleaning effect. Possibly. However, such a Zwischenspülschritt also completely eliminated.

In the now subsequent rinse step KS an application of items to be washed with hot water from the hot water supply is provided. For this purpose, the hot water valve 6 is first opened again until the washing container 2 is charged with a sufficient amount of hot water from the hot water supply WH for the final rinse step KS. The filled in the washing container 2 hot water is now circulated by means of the circulation pump 22 for a predetermined time, so as to pressurize the dishes with hot water. During the rinsing step KS, too, the heating device of the circulating pump 22 can be switched on as required as a function of the temperature of the hot water supplied and as a function of its intended rinsing temperature. At the end of the final rinse step KS, the now polluted hot water is pumped out by means of the drain pump 24 to the outside.

The rinse step KS is used in particular to avoid stains on the dishes, which could be caused by dissolved substances in the water, such as salt and / or lime. Although such solutes can be reduced by the intended softening device, but not completely removed. Therefore the water is added during the rinse step KS with rinse aid. Another object of the rinsing step KS is to prepare a subsequent drying step TS. Thus, the dishes are heated by hot water in particular, having for example a temperature of about 60 ⁰ C to 75 ° C, is used during the rinsing step KS. As a result, water droplets adhering to the hot dishes evaporate in the subsequent drying step TS and precipitate on the inside of the washing container 2 due to the lower temperature prevailing there. When using hot water from the hot water supply WH for the final rinse step KS is thus also ensured that the heat energy withdrawn from the hot water supply WH is used meaningfully. Again, a high saving in electrical energy can be achieved because the hot water from the hot water supply WH in many cases not, in other cases only to a small extent, must be reheated by the electric heater of the circulation pump 22 of the dishwasher 1 to the for to reach the rinse step KS required temperature.

Instead of providing a heater in the circulation pump 22, it may also be appropriate to provide a heater additionally or independently thereof at another suitable location in the liquid circuit of the dishwasher.

During the final drying step TS, a feeding of the washing container 2 with water is not provided.

According to the advantageous exemplary embodiment of FIGS. 1 to 3, the dishwasher has a hot water connection and at the same time a cold water connection, ie a bithermal water connection or two inlet side water connections for the inlet of water with different temperatures. These two water connections are each separately with a controllable valve, in particular an aquastop valve, controlled, in particular open and closed again. In particular, a rinsing program is provided in which, for pre-rinsing, for cleaning and for rinsing, hot water from an external hot water supply system, in particular from a thermal water supply system, is advantageously provided. mix solar system, is used. In this washing program, the brine is sent with cold water from a cold water supply in the ion exchanger, in particular pressed in a regeneration process. Likewise, the flushing of the ion exchanger takes place after the regeneration process with cold water. This program guide does not unnecessarily use warm water. There is an energy saving.

In particular, it may be appropriate, instead of or in addition to the solar thermal system for providing a cost domestic hot water supply a modern condensing boiler such as a Pelletofen-, wood chips, or Holzscheitheizung, a combined heat and power plant, geothermal heat pump, air heat pump system, a district heating system or a local heating system, individually or in any combination, etc to use. In particular, the combination of, for example, a pellet stove with a thermal solar system can be energetically advantageous. In particular, other hot water supply systems, which manage without or only with relatively low primary energy demand from fossil fuel carriers, are particularly favorable in terms of energy and / or use only largely CO ₂ -neutral energy carriers. The explanations given in the case of a solar thermal hot water production plant apply in the presence or presence of another hot water supply system with regard to the design and control of the dishwasher according to the invention in an analogous manner.

LIST OF REFERENCE NUMBERS

1 dishwasher

2 rinse tanks

3 door

4 housing

5 water inlet device

6 hot water valve

7 hot water hose

8 cold water valve

9 cold water hose

10 connector

1 1 inlet hose

12 housing-fixed connection piece

13 free flow path

14 ion exchanger

15 regenerating brine device

16 pump pot

17 wastewater connection piece

18 sewage hose

19 flow control device

20 controllable water distributor, water separator

21 process

22 Circulation pump with instantaneous water heater

23 spraying device

24 drain pump, sewage pump

A sewage pipe

DL data line

VL fluid connection line

KH cold water supply, cold water tap

WH hot water supply, hot water tap

RM regenerant SWV Switching state of the hot water valve SKV Switching state of the cold water valve BAP Operating state of the sewage pump SWA Switching state of the water switch SP Rinsing program VS Pre-rinsing step RS Cleaning step ZS Intermediate rinsing step KS Final rinsing step TS Drying step RES Regenerating step DS Rinsing step

Claims

claims 1. Dishwasher, in particular domestic dishwasher (1), with a water inlet device (5) for receiving water, with a by the water inlet device (5) chargeable softening device (14, 15, 20), which an ion exchanger (14) for softening and / or Desalting of water and a maintenance device (15, 20) for the maintenance of the ion exchanger (14), and with a sequence control device (19), in which at least one wash program (SP) is deposited for controlling a wash cycle for cleaning items, characterized characterized in that the water inlet device (5) has a hot water inlet (6, 7) and a cold water inlet (8, 9), wherein the hot water inlet (6, 7) for receiving hot water from an external hot water supply (WH) and the cold water inlet (8, 9) for receiving cold water from an external cold water supply (KH) are provided, wherein the respective selected wash program (SP) at least one program mschritt (VS, RS, ZS, KS) for flushing items using hot water from the hot water supply (WH), and wherein at the expiration or after the expiration of this selected wash program (SP) at least one program step (RES, DS) to wait the ion exchanger (14) is provided by means of the maintenance device (15, 20) using cold water from the cold water supply (KH) if maintenance of the ion exchanger (14) is requested by the process control device (19). 2. Dishwasher according to the preceding claim, characterized in that the washing program (SP) provides a regeneration step (RES) for servicing the ion exchanger (14), wherein the ion exchanger (14) is exposed to a regenerating brine, which using cold water from the cold water supply (KH) and regenerating agent (RM) of the maintenance device (15, 20) is prepared. 3. Dishwasher according to claim 2, characterized in that the regeneration step (RES) comprises a substep in which the maintenance device (15, 20), in particular their Regeneriersoleeinrichtung (15), cold water from the cold water supply (KH) is supplied to Regenerierso so - Ie from the Regeneriersoleeinrichtung (15) in the ion exchanger (14) to press. 4. Dishwasher according to one of the preceding claims, characterized in that the wash program (SP) provides a rinsing step (DS) for servicing the ion exchanger (14), wherein the ion exchanger (14) is flushed with cold water from the cold water supply (KH), so as to rinse regenerating brine from the ion exchanger (14). 5. Dishwasher according to one of the preceding claims, characterized in that the washing program (SP) provides a cleaning step (RS) for rinsing items to be washed, in which a loading of items to be washed with hot water from the hot water supply (WH). 6. Dishwasher according to one of the preceding claims, characterized in that the wash program (SP) provides a rinse step (KS) for washing items to be washed, in which a loading of items to be washed with hot water from the hot water supply (WH). 7. Dishwasher according to one of the preceding claims, characterized in that the wash program (SP) provides a pre-rinse step (VS) for rinsing items to be washed, in which, in preparation for a cleaning step (RS), loading of items with hot water from the hot water supply (WH) he follows. 8. Dishwasher according to one of the preceding claims, characterized in that the rinsing program (SP) provides an intermediate rinse step (ZS) for rinsing items to be washed in the removal of detergent from the items to be washed after a cleaning step (RS) an application of items to be washed with hot water the hot water supply (WH) takes place. 9. Dishwasher according to one of the preceding claims, characterized in that the hot water inlet (6, 7) comprises a hot water valve (6) and the cold water inlet (8, 9) comprises a cold water valve (8), wherein the hot water Water valve (6) and the cold water valve (8) independently of each other by the flow control device (19) are controllable. 10. Dishwasher according to claim 9, characterized in that the hot water valve (6) at an upstream end of a hot water hose (7) is arranged and adapted to be attached to a connecting piece (WA) of the external hot water supply (WH), and / or that the cold water valve (8) is arranged at an upstream end of a cold water hose (9) and adapted to be fastened to a connection piece (KA) of the external cold water supply (KH). 1 1. Dishwasher according to one of the preceding claims, characterized in that a downstream end of the hot water hose (7) and a downstream end of the cold water hose (9) via a connecting piece (10) liquid-conducting, in particular with the aid of a supply hose (11), is connected to a housing-fixed connection piece (12) of the dishwasher (1). 12. A method for servicing the ion exchanger (14) of a dishwasher (1), in particular domestic dishwasher, with a water inlet device (5) for receiving water, with a by the water inlet means (5) chargeable softening device (14, 15, 20), which ion exchanger (14) for softening and / or desalting water and a maintenance device (15, 20) for servicing the ion exchanger (14), and with a sequence control device (19) for controlling the rinse cycle of at least one rinsing program (SP) for the cleaning of Wash ware, in particular according to at least one of the preceding claims, characterized in that the water inlet device (5) with its hot water inlet (6, 7) for receiving hot water from an external hot water supply (WH) from the respective selected wash program (SP) of the flow control (19) and with its cold water inlet (8, 9) for taking cold water from an external cold water supply ( KH) is controlled such that the selected washing program (SP) at least one program step (VS, RS, ZS, KS) for washing items to be washed using hot water from the Hot water supply (WH) and at the expiration or after the expiration of this selected wash program (SP) at least one program step (RES, DS) to maintain the ion exchanger (14) by means of the maintenance device (15, 20) using cold water from the cold water supply (KH) is performed, if a maintenance of the ion exchanger (14) by the flow control device (19) is requested.