EP2440107A1

EP2440107A1 - Dishwasher comprising a heat exchanger and corresponding control method

Info

Publication number: EP2440107A1
Application number: EP10720179A
Authority: EP
Inventors: Roland Rieger; Michael Rosenbauer
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2009-06-10
Filing date: 2010-06-01
Publication date: 2012-04-18
Also published as: US20120073608A1; DE102009026876A1; WO2010142569A1

Abstract

The invention relates to a dishwasher, especially a domestic dishwasher (1), comprising a tub (2) for accommodating dishes, a water inlet device (5) for receiving water from at least one external water supply (WH, KH), at least one storage tank (14) which can be supplied with water by the water inlet device (5) and which is in heat-conducting contact with the tub (2) 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) comprises 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 wash program (SP) has at least one program step (RS, ZS, KS) for washing dishes using hot water from the hot water supply (WH) and at least one drying step (TS) for drying the dishes, the storage tank (14) being at least temporarily filled with cold water from the cold water supply.

Description

Dishwasher with heat exchanger and associated control method

The present invention relates to a dishwasher, in particular a domestic dishwasher, with a washing container for receiving items to be washed, with a water inlet device for receiving water from at least one external water supply, with at least one feedable by the water inlet device with water reservoir, in heat-conducting contact with the washing stands and with a flow control device, in which at least one rinse program for controlling at least one rinse cycle for cleaning items to be stored is stored.

In modern dishwashers, the items to be washed, in particular items to be washed, are introduced into a washing container and are there cleaned in a rinsing process, which is also called a rinse, with the aid of water and then dried. The aim is in particular to perform a rinse cycle 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 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 include several dimensions, for example the energy requirement, the water requirement and / or the time required. Furthermore, the drying efficiency corresponds 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 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 is 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, rinsing 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 dishes in this order, a typical washing program comprises, in particular, a pre-rinsing step, a cleaning step, an intermediate rinsing step and a rinsing step in which the items to be washed are each supplied with water. However, it is also possible to provide rinsing programs in which one or more of these program steps are hidden. For example, the intermediate rinse step can be omitted. Also, rinse programs are possible in which one or more of these program steps are repeated several times. Furthermore, a typical washing program includes an adjoining drying step for drying the cleaned items to be washed.

A pre-rinse step serves primarily to remove coarse contaminants from the items to be washed. The purpose of a subsequent cleaning step is, in particular, to completely remove soiling from the items to be washed. A now performed intermediate rinsing step serves in particular for the removal of detergent residues which adhere to the items to be washed. A subsequent rinse step is intended in particular to avoid stains on the items to be washed, which could be caused by dissolved substances in the water, such as, for example, 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 the subsequent drying step. For this purpose, the items to be washed can be heated to a high temperature during the rinse step. In the final drying step, water droplets and conditions on the inside of the washing due to the prevailing lower temperature.

Known dishwashers have a reservoir that can be charged with water by the water feed device and that is in heat-conducting contact with the washing container and is referred to in practice as a "heat exchanger." During the drying step, this reservoir is filled with water around at least part of the wall of the washing container In this way, the condensation of water vapor on the inside of the washing container and thereby in turn the evaporation tendency of water drops adhering to the items to be increased, so that the drying result with the same use of time and energy is significantly improved The temperature to which the items to be washed are heated during the rinse step can be set lower, thus resulting in a higher drying efficiency compared to a dishwasher without a reservoir.

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 storage container 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 storage container, which enables a more efficient performance of rinse cycles.

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, wherein the hot water supply for receiving hot water from an external hot water supply and the cold water inlet for receiving cold water from an external cold water supply provided are, wherein the rinse program at least one program step for rinsing dishes by using hot water from the hot water supply and at least one drying step for drying items to be washed, wherein the reservoir is at least temporarily filled with cold water from the cold water supply.

Dishwashers and in particular household dishwashers are usually operated in locations where a hot water supply and a cold water supply is 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 preferably 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, makes it possible to carry out 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. In this way, both compared to known dishwashers, which are - as usual especially in Europe - are provided exclusively for connection to a cold water supply, as well as against known dishwashers, which - as usual especially in North America - exclusively for connection to a hot water supply a significant increase in efficiency can be achieved.

If a program step of a selected, running dishwasher program by its nature requires or at least makes desirable the use of water at a high temperature, hot water may 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 boiler, a combined heat and power plant or a district heating system or a local heating system for hot water supply is available. However, the cost advantage can be further increased if the household has a geothermal heat pump or in particular a solar system for generating the hot water.

Furthermore, for a program step in which the use of high temperature water has no advantages or disadvantages, cold water can be taken up from 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 uptake of cold water from the external cold water supply can reduce the amount of hot water which must be taken from the external hot water supply for a rinse, without resulting in substantial disadvantages with respect to the cleaning effect and / or the drying effect. kung would have to be accepted. 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 flow control device, which at least one program step for washing items by using hot water from the hot water supply and at least one program step for drying items in which the reservoir at least temporarily Cold water is filled from the cold water supply, provides.

In a program step for rinsing items to be washed, the achievable cleaning effect depends in particular 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, characterized in that the reservoir is at least temporarily filled with cold water from the cold water supply during the drying step, causes a particularly strong cooling of at least a portion of the wall of the washing container of the dishwasher, so that the condensation of water vapor is promoted all the more. In this way, in turn, the tendency to evaporation of adhering to the wash water drops is particularly greatly increased, so that the drying result compared to dishwashers, which are connected exclusively to a hot water supply and in which the reservoir must therefore be filled with hot water, is significantly improved. The intended drying effect can be achieved in a much shorter time. As a result, the drying efficiency increases considerably. In addition, results over conventional dishwashers, where the Reservoir during the drying step can only be filled with hot water, a lower load on the external hot water supply. 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 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, therefore, a temperature of about 50 ⁰ C to 70 ⁰ C is 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 for the cleaning step to reach.

According to an advantageous development of the invention, the rinsing program provides a rinsing step for rinsing items to be washed, in particular after the one rinsing step, if necessary, following intermediate rinsing step, 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, during the rinse step, the dishes are heated by using particularly hot water, which for example has a temperature of 60 ° C to 75 ° C is used. In the final drying Step on the hot crockery adhering drops of water and precipitate on the inside of the washing due to the prevailing lower temperature there. In conjunction with the filled with cold water from the cold water supply tank, which cools at least a portion of the inside of the washing, results in an extremely short time an excellent drying result. 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 does not have to be reheated in other cases, only to a small extent by the electric heater of the dishwasher to reach the minimum temperature required for the rinse step ,

According to an advantageous development of the invention, the rinsing program optionally provides an intermediate rinsing step, in particular between the cleaning step and the rinsing step, for rinsing items to be washed, in which removal of detergent from the items to be washed after a cleaning step, 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 an advantageous development of the invention, the rinsing program provides at least one program step for rinsing items to be washed, in particular a pre-rinse step and / or a cleaning step, in which an application of items to be washed with cold water from the cold water supply, which during a drying step of a previous rinse cycle in the reservoir was filled. By storing the water of a drying step of a first rinse cycle for a program step of a subsequent rinse cycle, the water requirement for this rinse cycle can first be lowered. To- the cold water can during its storage to ambient temperature, which is typically higher in a household by 5 ° C to 10 ⁰ C, than the temperature of the cold water when it is removed from the cold water supply. As a result, preheated water is available to a certain extent for a program step of the rinse cycle carried out later, without this burdening the hot water supply. In this way, the overall efficiency of the dishwasher continues to increase.

According to an advantageous development of the invention, the rinsing program provides at least one program step for rinsing items to be washed, in particular a pre-rinsing step, a cleaning step, an intermediate rinsing step and / or a rinsing step in which items are treated with warm water from the hot water supply, which during a temporally preceding program step of the same rinse was filled in the reservoir. In this way, in many cases, the temperature of the hot water can be increased before it is even used to load dishes. This procedure is particularly worthwhile if the temperature of the hot water supply is comparatively low, ie, for example between 40 ° and 50 ⁰ C, and the water in the washing container by means of the heater of the dishwasher to a higher temperature, ie for example to 60 ⁰ C or even 70 ° C, heated. In this way, a recovery of heat energy from the water in the washing container is possible before it is pumped to the outside, so that the efficiency increases further.

According to a particularly preferred development of the invention, the rinsing program provides for a filling of the reservoir with cold water from the cold water supply, in particular after completion of the final rinse step of the rinse program, at the beginning and / or during the drying step of the respective running rinse program. A drying step of a washing program usually follows immediately after a final rinse step. While circulating relatively hot water in the rinsing container during the rinse cycle, no circulation of water takes place during the drying step. Rather, at the beginning of the drying step, or shortly thereafter, the water which collects in a lower region of the washing container is removed from the dishwashing liquid. pumped off. If, as provided, the reservoir, in particular at the beginning or during the drying cycle, and not before, is fed with cold water, it is prevented that the water in the reservoir is heated by the hot water of the rinse step.

According to a preferred embodiment of the dishwasher according to the invention, the flow control device is adapted to adapt a washing program in the absence of connection between the hot water supply and the hot water supply or in the absence of connection between the cold water inlet and the cold water supply. In this case, sensors may be present, by which the flow control device detects whether the hot water supply or the cold water supply is connected to a water supply or not. The sensors may in particular be flow sensors or pressure sensors. In addition, temperature sensors are conceivable, so that it can also be detected whether the respective water inlet device is connected to a cold water supply or to a hot water supply. The adaptation of the washing program, for example, done so that when a hot water supply is not connected hot water is replaced by cold water, which is then heated in the washing as far as necessary. In the absence of cold water supply, for example, the step "filling the reservoir with water during the drying step" can be omitted.

According to an advantageous embodiment of the invention, the reservoir is flat against the washing. In this way, a good heat transfer from the washing container to the reservoir is possible. Elaborate Wärmeleitkomponenten are not required. As a result, a significant improvement in the drying result of the dishwasher is achieved with little design effort.

According to an advantageous embodiment of the invention, the reservoir is a plastic part. Such containers can be produced, for example, by means of suitable extrusion or casting methods with low production costs. In addition, reservoirs made of plastic have a certain flexibility, so that they are suitable for fastening, especially when they are filled, cling particularly well to the washing container, which again improves the drying efficiency.

According to an expedient development of the dishwasher according to the invention, the storage container is arranged on a side wall, bottom wall and / or rear wall of the washing compartment. The side wall of a washing container is sufficiently stable to carry a filled storage container. In this way, it is possible, particularly with a side wall connection of the storage container, to fix the storage container directly to the washing container, which improves the heat transfer from the washing container to the storage container. In addition, the side wall of a washing container is substantially flat, so that the production of a flat contact between the reservoir and washing container is possible in a simple manner. Thus, for example, a simple to produce cuboid reservoir can be used.

According to an advantageous embodiment of the invention, the reservoir is disposed at an upper portion of the washing container. Since in the upper portion of the washing container during the drying cycle higher temperatures prevail, as in a lower portion, in this way the condensation of water vapor in the washing further improved, which further improves the drying result. In addition, the arrangement allows an easy emptying of the reservoir by gravity at an upper portion of the washing container.

According to an advantageous embodiment of the invention, the hot water inlet device and / or the cold water inlet device is associated with a free flow path. The free flow path or the free flow paths can be arranged for example in the reservoir. The free flow paths avoid sucking back of water in the direction of the hot water supply or the cold water supply, which could occur at a temporary negative pressure resulting from dynamic processes. In this way, in particular a too low water level in the reservoir and / or in the washing can be avoided. According to a preferred development of the invention, it is provided that the hot water inlet comprises a hot water valve and the cold water inlet comprises a cold water valve, wherein the hot water valve and the cold water valve are independently controllable by the sequence 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 is provided that the hot water valve is arranged at an upstream end of a hot water hose and adapted to be fastened to a fitting of the external hot water supply, and / or that the cold water valve is arranged at an upstream end of a cold water hose and so is formed so that it is attachable to a connector of the external cold water supply. The hot water valve and / or the cold water valve can for this purpose have connection threads, for example, which correspond with threads of household faucets. Such valves are also known as Aquastop valves.

The arrangement of the hot water valve and / or the cold water valve at the upstream end of the 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 also to prevent leakage of leakage water from a switched-on dishwasher, the flow control device may be associated with a leak water sensor for detecting leakage water, so that the flow control device can close the valves when leak 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, preferably Y-connector, liquid-conducting, in particular via its output side, common inlet hose, are connected to a housing-fixed connection piece of the dishwasher. Such a design of the water inlet device is structurally simple and significantly shortens the 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, since in this case dispensed two longer parallel tubes can.

The invention further relates to a method for controlling at least one rinse cycle of a dishwasher, in particular domestic dishwasher, by means of at least one rinse program a flow control device, the dishwasher a rinse container for receiving items to be washed, a water inlet device for receiving water from at least one external water supply, and at least one by the water inlet device with water feedable reservoir, which is in heat-conducting contact with the washing, has, which is characterized in that the washing program at least one program step for washing dishes is performed, is used in the hot water from an external hot water supply by means of a hot water supply, and at least one drying step for drying items to be washed is carried out by the washing program, in which case the storage container is at least temporarily filled with cold water an external cold water supply is filled by means of a cold water inlet.

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

The invention and its developments 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;

FIG. 3 shows a schematic functional diagram for explaining the function of the dishwasher of FIGS. 1, 2.

In the following figures, corresponding parts are provided with the same reference numerals. In this case, only those components of a dishwasher are provided with reference numerals and explained, which are necessary for the understanding of the invention. 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 advantageous 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 rinsing cell is produced for rinsing items to be washed. The rinsing container 2 is arranged in the interior of a housing 4 of the dishwasher 1, which has standard dimensions. Thus, the housing 4, for example, have a width of 45 cm or 60 cm, which allows integration of the dishwasher 1 in a standard designed kitchenette with a corresponding Einbaunische.

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.

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. Das Warmwasserven- til 6 and cold water valve 8 are basically identical. For example, both valves 6, 8 may be formed as a solenoid valve. The inlet sides of the valves 6, 8 are each designed so that they can be attached to fittings of a domestic hot water supply WH and cold water supply KH, for example to taps (hot water tap and cold water tap). 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 to a cold water hose 9, wherein 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. At its output side, a common inlet hose 11 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 so that the leakage water channels of the hot water water hose 7, the cold water hose 9 and the common inlet hose 11 are connected to each other, so that leakage water, which occurs during operation of the dishwasher 1 in the water supply device 5, is passed through the housing-fixed connector 12 in the interior of the dishwasher 1. 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 embodiment variant, the common inlet hose can possibly be saved. In particular, the connection piece 12 may be provided together with the Y-connector 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.

Furthermore, the dishwasher 1 has a reservoir 14 as a heat exchanger, which is connected by means not shown in the figure 1 so with the free flow path 13 that it can be filled with cold water from the cold water supply KH and / or hot water from the hot water supply WH , It is arranged on a side wall 15 of the washing container 2 so that heat transfer from the washing container 2 to the storage container 14 is possible. The reservoir 14 is formed as a very flat cuboid. He is in particular shaped like a dish or plate. Thus, for example, its width is about 2 cm, so that it can be readily arranged between the side wall 15 of the washing container 2, in particular between its bitumen coating, and a wall of an outer housing of the dishwasher 1. Height and depth of the washing container, for example, each be between 40 and 50 cm. As a result, a container volume of, for example, 3 to 4 l can be achieved. This amount is sufficient to carry out a program step for rinsing items to be washed, for example a pre-rinse step, a cleaning step, an intermediate rinse step and / or a final rinse step, with water alone from the storage container 14. Due to the flat design results in a large contact area between the washing compartment 2 and the reservoir 14. In this way, a good heat transfer is possible.

While the washing container 2 may be made of stainless steel, the reservoir 14 is preferably made of plastic. The reservoir 14 may in particular consist of polypropylene, which is a cheap and easy to process plastic. Thus, the reservoir 14 can be produced in a simple manner by extrusion or casting process. Since the side wall 15 of the washing container 2 is made substantially flat, and the inwardly facing heat contact surface of the reservoir 14 is flat and therefore easy to produce. In particular, when the storage container 14 is filled, it nestles particularly well due to its material-related flexibility of the washing container 2, in particular its outer bitumen layer. As a result, the heat transfer is again positively influenced. The bituminous layer in the side wall of the washing container has been omitted in FIG. 1 for the sake of simplicity of drawing.

During a drying step of a washing program of the dishwasher 1, the inside of the side wall 15 of the washing container 2 is cooled due to the heat-conductive contact between the reservoir 14 and the washing container 2. In order to maximize this cooling, it is provided that the reservoir 14 is at least temporarily filled with cold water from the cold water supply KH during the drying step. As a result, a condensation of water vapor in the washing container 2 located on the side wall 15 is amplified. this leads to a better drying result when carrying out the washing program. The reservoir 14 is arranged at an upper portion of the washing container 2, since there are usually higher temperatures than in a lower portion, so that the cooling of the side wall just here leads to a particularly good drying effect.

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 block 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, that both are individually controlled. This makes it possible to selectively fill the reservoir 14 via the connecting piece 10 and the free flow path 13 with hot water and / or cold water. At the lower end of the reservoir 14, a drain valve 20 is provided, which downstream of a drain 21 connects, which opens into the washing compartment 2. The drain valve 20 is also controllable by the flow control device 19. In this way, it is possible to flow in the reservoir 14 located water depending on the selected wash program in the washing compartment 2.

In the sump 16 of the washing container 2, a circulating pump 22 is arranged, which in this embodiment additionally has an electric heater in the embodiment. It is connected to a spray system 23 arranged inside the washing container 2. This makes it possible to apply washware arranged in the washing container 2 during a wash cycle in order to clean it. Furthermore, a drain pump 24 is arranged in the sump, which makes it possible to pump out no longer needed water to the outside. When the circulation pump 22 is both - if a heater is present - the heating function and the pumping function by the flow control device 19 individually controlled. Furthermore, the flow control device 19 is also connected to the drain pump 24 for the control thereof. The heater is used in particular to bring the water to a desired minimum temperature for the respective program step, if the present temperature of the incoming water is below the respective required minimum temperature. It may additionally or independently of the circulating pump also be provided at another suitable location of the liquid circulation system of the dishwasher.

The loading of the reservoir 14 with water as well as the control of the drain valve 20, the circulation pump 22, their possibly existing heater and the drain pump 24 and other not explained here devices of the dishwasher 1 as a function of the respective selected wash program, which in the flow control device 19th is stored. Here, in the exemplary embodiment of the present dishwasher 1, at least one washing program is provided which can be selected specifically for the efficient use of hot water from the hot water supply WH and cold water from the cold water supply KH.

FIG. 3 shows a functional diagram for explaining the function of the dishwasher 1 of FIGS. 1 and 2. For this purpose, the sequence of a washing program SP is shown, which is provided for controlling a course of a washing cycle in this way. ensure efficient use of hot water from hot water supply WH and cold water from cold water supply KH.

FIG. 3 shows on a common time axis t the curves SWV, SKV, SAV and BVB 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 the cold water valve 8 of the dishwasher 1. The curve SAV, however, represents the switching state of the drain valve 20. The switching state "0" corresponds in each case to a closed Valve 6, 8, 20, the switching state "1" an open valve 6, 8, 20. The curve BVB finally shows the filling state of the reservoir 14 with water. Here, a filled with hot water from the hot water supply WH reservoir 14 with "WW", filled with cold water from the cold water supply KH reservoir 14 with "KW" and an empty reservoir 14 by "0".

FIG. 3 shows by way of example a rinsing program SP, which in this sequence 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 initially performed pre-rinsing step VS serves to remove coarse contaminants from the items to be washed in order thus to prepare the cleaning step RS. At the beginning of the pre-rinsing step VS, the storage container 14 is filled with cold water from the cold water supply KH, which was used during the execution of a drying step TS of a previously performed rinse cycle for cooling the rinsing container 2. The storage of the cold water of the previous wash cycle reduces the water consumption of the dishwasher. In addition, the stored cold water in the reservoir substantially ambient temperature, which is usually higher than the temperature at which the cold water is taken from the cold water supply. This cold water is passed at the beginning of Vorspülschritts VS by temporarily opening the drain valve 20 in the washing tank 2 and circulated by means of the circulation pump 22 for a predetermined time, so as to pressurize the dishes with cold water.

If heating of the water during the pre-rinsing step is not provided, the preheating of the cold water to room temperature leads directly to a higher pre-rinse temperature, which increases the cleaning effect without further energy consumption. However, if during the Vorspülschritts a heating of the cold water z. B. is provided by means of a heater in the circulation pump 22 to a predetermined minimum temperature, the energy required to achieve the predetermined temperature decreases. As a result, in both cases the efficiency of the dishwasher 1 is improved in comparison to a dishwasher in which cold water is drawn from the cold water supply KH immediately before or during the pre-rinsing step VS. In comparison to a dishwasher in which hot water from the hot water supply WH is obtained for the pre-rinsing step VS, the amount of heat removed from the hot water supply WH can also be reduced.

During the pre-rinse step VS, the hot water valve 6 is temporarily opened so as to fill the previously empty reservoir 14 with hot water from the hot water supply WH. If, during the pre-rinse step VS, the temperature of the water in the rinse tank 2, z. B. by heating by means of the heating of the circulation pump 22, is higher than the temperature of the hot water supply, so at least a portion of the heat energy of the existing water in the washing tank 2 by heat transfer to the reservoir 14 are recovered before this now polluted water (in not shown) is pumped out by means of the drain pump 24 to the outside.

The subsequent cleaning step RS is used to thoroughly clean the dishes. At the beginning of the cleaning step RS, the reservoir 14 is filled as shown with hot water from the hot water supply WH. At this time, the drain valve 20 is temporarily opened to open the flush valve. container 2 with this hot water from the hot water supply WH to fill. The filled in the washing tank 2 hot water is now circulated by means of the heat pump 22 for a predetermined time, so as to pressurize the dishes with hot water. In this case, the heating device of the heating pump 22 can be switched on as required as a function of the temperature of the supplied hot water and in dependence on the intended washing temperature of the cleaning step RS. Also, during the cleaning step RS, the reservoir 14 is filled again by temporarily opening the hot water valve 6 with hot water from the hot water supply WH, which may further heat up here when the temperature in the washing tank 2 is sufficient. At the conclusion of the cleaning step RS, the now polluted hot water is pumped out (not shown) by means of the drain pump 24 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 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 of 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 heating pump 22 of the dishwasher 1, to the required minimum temperature to reach.

The now performed intermediate rinse step ZS for removing detergent from the dishes after the cleaning step RS is done using hot water from the hot water supply WH, which was filled during the cleaning step RS in the reservoir 14. For this purpose, first the drain valve 20 is briefly opened again to feed the washing container 2 with hot water. This hot water is by means of the circulation pump 22 for circulated a predetermined time, which usually can be omitted switching on the heating device. Thereafter, the now polluted hot 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 an energy saving, but the intermediate purging time would normally have to be extended in order to achieve a predetermined cleaning effect.

During the Zwischenspülschritts ZS the hot water valve is also temporarily opened to supply the reservoir 14 again with hot water from the hot water supply WH. This is available in the rinse step KS which follows for the supply of items to be washed, wherein the discharge valve 20 is again opened at short notice in order to charge the rinse container 2. The filled in the washing tank 2 hot water is now circulated by means of the heat 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.

A time-subsequent rinse step KS 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 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, comprising, for example, a temperature of 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 rinse step KS is thus also ensured that the Hot water supply WH extracted heat energy 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 at all, in other cases only to a small extent, must be reheated by the electric heater 22 of the dishwasher 1 to those for the final rinse step KS required minimum temperature to achieve.

The flushing program SP final drying step TS is used to dry the cleaning container located in the washing container 2 and cleaned. The temperature of the items to be washed is relatively high at the beginning of the drying step due to the preceding rinsing step, so that water adhering to the items to be washed evaporates. At the same time, the walls of the washing container 2 cool down by releasing heat to the outside. This results in a temperature difference between the items to be washed located in the washing container 2 and the insides of the walls of the washing container 2, so that the evaporated water condenses on the walls. The further evaporation is the better, the more water condenses out.

To promote this condensation, the reservoir 14 is filled after completion of the rinse step KS, at the beginning and / or during the drying step TS by opening the cold water valve 8 with cold water. As a result, the temperature of the side wall 15 decreases further. After filling the reservoir 14, the cold water valve 8 is closed again. At a time, which is predetermined by the washing program, the drying step TS and the washing program SP is completed altogether, wherein the cold water remains in the reservoir 14 and is kept there for a later rinse. Due to the cooling of the washing container 2 by the cold water in the reservoir 14 can be achieved in a short time an excellent drying result, so that there is a good drying efficiency.

The invention relates in an advantageous embodiment, the so-called heat exchanger technology by means of at least one reservoir, which is in heat-conducting contact with the washing container of a dishwasher. The dishwasher is equipped with a hot water connection, in particular hot water solar connection, and a cold water connection, ie it has a bithermic water connection. In this case, in an expedient exemplary embodiment of a dishwasher according to the invention, preferably two water connections - a hot water connection and a cold water connection - are provided, which can be controlled separately with one valve each, in particular Aquastop valve. In particular, a first water connection for warm, inexpensive solar water and a second water connection for cold water from the pipe network are provided. Both water connections can be individually selected via a control of the dishwasher.

The dishwasher is equipped with the heat exchanger technology, whereby specially designed programs are stored in the control unit. If the customer chooses a special function, the machine can react to it. All programs are adjusted so that the device responds accordingly to the hot water connection, in particular the solar hot water connection, and the cold water connection from the pipe network.

In particular, a rinsing program can be provided in which, for cleaning, intermediate rinsing and rinsing, previously filled hot water, which originates from a solar installation, is taken from the storage container. In this washing program continues to be filled in a drying process, the reservoir with cold water from a cold water supply to create a sufficiently cold condensation surface. This cold water is removed from the reservoir for a pre-rinse step of a subsequent rinse cycle

By using cold water to create a condensation surface drying performance remains at a high level, despite hot water connection, in particular hot water connection to a hot water solar system. This creates an energy-saving program with very good drying performance. 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 storage tank, heat exchanger

15 side wall

16 pump pot

17 wastewater connection piece

18 sewage hose

19 flow control device

20 drain valve of the reservoir

21 process

22 circulation pump

23 spraying device

24 drain pump, sewage pump

A sewage pipe

KH cold water supply, cold water tap

WH hot water supply, hot water tap

SWV Switching state of the hot water valve SKV Switching state of the cold water valve SAV Switching state drain valve BVB filling status of the storage container

SP wash program

VS pre-rinse step

RS cleaning step

ZS intermediate rinse step

KS rinse step

TS drying step

Claims

claims

1. Dishwasher, in particular domestic dishwasher (1), with a washing container (2) for receiving items to be washed, with a water inlet device (5) for receiving water from at least one external water supply (WH, KH), with at least one by the water inlet device (5 ) can be fed with water supply container (14), which is in heat-conducting contact with the washing container (2) and with a flow control device (19), in which at least one washing program (SP) for controlling at least one wash cycle for cleaning items to be stored, 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 ) are provided for receiving cold water from an external cold water supply (KH), wherein the rinsing program (SP) at least one n program step (RS, ZS, KS) for rinsing items to be washed using hot water from the hot water supply (WH) and at least one drying step (TS) for drying items in which the storage container (14) at least temporarily filled with cold water from the cold water supply is, provides.

2. Dishwasher according to the preceding claim, characterized in that the wash 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).

3. Dishwasher according to one of the preceding claims, characterized in that the rinse program (SP) provides a rinse step (KS) for rinsing items to be washed in which a loading of items to be washed with hot water from the hot water supply (WH).

4. Dishwasher according to one of the preceding claims, characterized in that the washing program (SP) an intermediate rinse step (ZS) intended for rinsing items to be washed, in which a loading of items to be washed with hot water from the hot water supply (WH).

5. Dishwasher according to one of the preceding claims, characterized in that the rinsing program (SP) at least one program step (VS) for rinsing items to be washed, in particular a pre-rinse step (VS) and / or a cleaning step (RS), provides, in which a loading of items to be washed with cold water from the cold water supply (KH), which was filled during a drying step (TS) of a previous rinse cycle in the reservoir (14).

6. Dishwasher according to one of the preceding claims, characterized in that the wash program (SP) at least one program step (RS, ZS, KS) for rinsing items to be washed, in particular a cleaning step (RS), an intermediate rinse step (ZS) and / or a rinse step (KS) provides, in which a loading of items to be washed with hot water from the hot water supply (WH), which during a previous program step (VS, RS, ZS) the same wash cycle in the reservoir (14) has been filled.

7. Dishwasher according to one or more of the preceding claims, characterized in that the washing program (SP) filling the reservoir (14) with cold water from the cold water supply (KH), in particular after completion of the rinse step (KS), at the beginning and / or during the drying step (TS) of the respective running program (SP).

8. Dishwasher according to one or more of the preceding claims, characterized in that the flow control device (19) for adjusting the washing program (SP) in the absence of connection between the hot water inlet (6, 7) and a hot water supply (WH) and / or lack of connection between the cold water inlet (8, 9) and a cold water supply (KH) is formed.

9. Dishwasher according to one of the preceding claims, characterized in that the storage container (14) rests flat against the washing container (2).

10. Dishwasher according to one of the preceding claims, characterized in that the storage container (14) is a plastic part, in particular made of polypropylene.

1 1. Dishwasher according to one of the preceding claims, characterized in that the storage container (14) on a side wall (15), bottom wall, ceiling wall and / or rear wall of the washing compartment (2) is arranged.

12. Dishwasher according to one of the preceding claims, characterized in that between the reservoir (14) and the washing compartment (2) an insulating, in particular heat-insulating and / or sound-insulating, insulating layer, in particular bitumen layer, is provided.

13. Dishwasher according to one of the preceding claims, characterized in that the storage container (14) is arranged on an upper portion of the washing container (2).

14. Dishwasher according to one of the preceding claims, characterized in that the hot water inlet (6, 7) and / or the cold water inlet (8, 9) is associated with a free flow path (13) is / are.

15. 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 valve (6) and the cold water valve ( 8) are independently controllable by the flow control device (19).

16. Dishwasher according to one of the preceding claims, characterized in that the hot water valve (6) at an upstream end of a hot water hose (7) is arranged and designed so that it is attachable to a connection piece (WH) of the external hot water supply (WH), and / or that the cold water valve (8) at an upstream end of a cold water hose (9) is arranged and formed at a connection piece (KH) of the external cold water supply (KH) can be fastened.

17. 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 on the output side, common inlet hose (11) , are connected to a housing-fixed connection piece (12) of the dishwasher (1).

18. Dishwasher according to one of the preceding claims, characterized in that the hot water supply (WH) is provided by a solar thermal system.

19. A method for controlling at least one wash cycle of a dishwasher (1), in particular domestic dishwasher, by means of at least one wash program (SP) of a sequence control device (19), wherein the dishwasher (1) comprises a wash container (2) for receiving items to be washed, a water inlet device (5 ) for receiving water from at least one external water supply (WH, KH), and at least one by the water inlet device (5) with water feedable reservoir (14), which is in heat-conducting contact with the washing compartment (2), in particular after at least one of the preceding claims, characterized in that the washing program (SP) at least one program step (RS, ZS, KS) is performed for rinsing items to be used in the hot water from an external hot water supply (WH) by means of a hot water inlet (6, 7) is, and that the washing program (SP) at least one drying step (TS) for Drying of items to be washed is performed, in which the storage container (14) at least temporarily with cold water from an external cold water supply (KH) by means of a cold water inlet (8, 9) is filled.