EP4373378B1 - Domestic dishwasher having a sorption drying system and associated method for carrying out an energy-saving dishwashing program - Google Patents

Description

• mit einem Spülraum zur Aufnahme von zu reinigenden Spülgutteilen,
• mit einer Steuer-/ Kontrolleinheit zur Durchführung von ein oder mehreren Geschirrspülprogrammen, wobei das jeweilige Geschirrspülprogramm ein oder mehrere Spülphasen, während der die zu reinigenden Spülgutteile mit Spülflüssigkeit beaufschlagt sind, und eine spülprogrammabschließende Trocknungsphase umfasst,
• und mit einem Sorptionstrocknungssystem, das
  • einen außerhalb des Spülraums angeordneten Umluftkanal, der einen Luftauslass des Spülraums mit einem Lufteinlass des Spülraums fluidisch verbindet,
  • einen in den Umluftkanal fluidisch eingefügten Sorptionsbehälter, in dem eine Festbettschüttung eines körnigen oder granulatförmigen, reversibel dehydrierbaren Sorptionsmaterials untergebracht ist,
  • eine in den Umluftkanal fluidisch eingefügte Luftfördereinheit, die zumindest während eines Zeitabschnitts, insbesondere Anfangszeitabschnitts, der Trocknungsphase des jeweilig durchzuführenden Geschirrspülprogramms feuchtwarme Spülraumluft aus dem Spülraum zu deren Entfeuchtung durch den Sorptionsbehälter zwangsfördert, und
  • eine Desorptions- Heizungsvorrichtung mit einer fest vorgegebenen Heizleistung umfasst, die zumindest zeitweise während einer Regenerationsphase, während der die Luftfördereinheit Spülraumluft durch den Umluftkanal zwangsfördert und die in mindestens einer Spülphase, insbesondere der Reinigungsphase, des jeweilig durchzuführenden Geschirrspülprogramms stattfindet, die dem Sorptionsmaterial zugeführte Spülraumluft unter Einbringung von Wärmeenergie derart aufheizt, dass das Sorptionsmaterial Wasser, das während der Trocknungsphase des zeitlich vorausgehenden Geschirrspülprogramms im Sorptionsmaterial gespeichert worden ist, desorbiert.

The invention relates to a household dishwasher

• with a washing chamber for holding items to be cleaned,
• with a control/monitoring unit for carrying out one or more dishwashing programs, wherein the respective dishwashing program comprises one or more rinsing phases during which the items to be cleaned are exposed to rinsing liquid, and a drying phase concluding the rinsing program,
• and with a sorption drying system that
  • a recirculation duct arranged outside the washing chamber, which fluidically connects an air outlet of the washing chamber with an air inlet of the washing chamber,
  • a sorption container fluidically inserted into the recirculating air duct, in which a fixed bed of a granular or granular, reversibly dehydratable sorption material is accommodated,
  • an air conveying unit fluidically inserted into the recirculating air duct, which, at least during a period of time, in particular the initial period of time, of the drying phase of the respective dishwashing program to be carried out, forcibly conveys warm, moist air from the dishwashing chamber for its dehumidification through the sorption container, and
  • a desorption heating device with a fixed heating power, which at least temporarily during a regeneration phase, during which the air conveying unit forcibly conveys dishwashing chamber air through the recirculation duct and which takes place in at least one rinsing phase, in particular the cleaning phase, of the respective dishwashing program to be carried out, which The air supplied to the washing chamber is heated by the sorption material by introducing thermal energy in such a way that the sorption material desorbs water that has been stored in the sorption material during the drying phase of the preceding dishwashing program.

To regenerate the granular or granular, particularly spherical, reversibly dehydratable sorption material of the fixed bed, the desorption heating device heats the washroom air, which is forcibly fed to this sorption material by means of the air conveying unit, at least temporarily during the regeneration phase, with a fixed or constant heating output using electrical energy. It is preferably designed as an electric air heater, which is provided in the recirculating air duct, viewed in the forced air flow direction of the air conveying unit, upstream of the inlet cross-sectional area of the fixed bed housed in the sorption container. It thus heats the washroom air, which is forcibly fed by the air conveying unit during the respective regeneration phase, upstream of its entry into the fixed bed, viewed in the direction of flow.

A household dishwasher of the type mentioned above is known, for example, from WO 2015/003933 A1 A control unit increases the speed of a fan provided in the recirculation duct of its drying system when the temperature in the drying system's container containing a super absorbent polymer reaches the upper limit of the regeneration temperature of this super absorbent polymer, as specified by the drying material manufacturer, in order to prevent it from overheating.

The DE 10 2013 101 673 A1 specifies a method for operating a dishwasher having a sorption drying device, in which a desorption process of the sorption drying device suitable for releasing moisture is carried out depending on a selected cleaning program. The amount of heat supplied to the sorption drying device during the desorption process is selected depending on the selected cleaning program. For this purpose, the amount of heat supplied is adjusted by specifying the duration and/or the supplied power.

The sorption drying system of the dishwasher DE 10 2014 222 539 A1 In recirculation mode, air is drawn from the wash tub by a fan through a sorption drying device and then back into the wash tub. During the drying phase of a program, the volume flow that can be fed back into the wash tub via an outlet opening or the exit velocity of the air that has passed through the sorption drying device is varied several times. The same can also be done during a desorption phase, during which a heating device provided upstream of and/or within the sorption drying device heats the air conveyed by the fan and/or the sorption material of the sorption drying device.

The DE 10 2013 213 359 B3 deals specifically with a commercial dishwasher designed as a programmable automatic dishwasher, which comprises a sorption unit in a recirculation duct and a fan arranged in front of it. To desorb the dry material of the sorption unit, air from the washing container is blown through the sorption unit by the fan, and thermal energy is supplied to the dry material by means of a heating device.

The DE 10 2012 000 013 A1 envisages a household dishwasher with a recirculation duct containing a sorber and a fan arranged upstream of it. The sorbent of the sorber, which is partially laden with water, is heated for desorption by direct, static heat supply (static desorption) without forced air movement. For this purpose, the sorbent is in direct contact with heating surfaces, which heat the sorbent during static desorption. The heating surfaces are embedded and not electrically insulated from the sorbent. After the end of the static heat supply, a post-ventilation follows, during which circulating air forced through the sorbent by the fan desorbs further water vapor from the sorbent.

The invention is based on the object of further improving the energy efficiency of a household dishwasher with a sorption drying system of the type mentioned above.

This object is achieved in a household dishwasher of the type mentioned at the outset in that a control logic for the regeneration phase of the respective dishwashing program changes the conveying volume flow of the wash cabinet air conveyed by the air conveying unit in a specific dependency on the respectively specified regeneration time duration of the regeneration phase of the respective dishwashing program in such a way that the inlet temperature of the wash cabinet air conveyed into the fixed bed during the regeneration phase of the respective dishwashing program and heated by means of the desorption heating device and thus the regeneration temperature brought about in the sorption material over the flow extension of the fixed bed is set in a specific dependency on the respectively specified regeneration time duration of the regeneration phase of the respective dishwashing program.

The control logic therefore adapts the volume flow of the wash cabinet air conveyed by the air conveying unit individually or specifically to the respective specified duration of the regeneration phase of the respective dishwashing program. If the control/monitoring unit provides several different dishwashing programs, such as an energy-saving dishwashing program, in particular a so-called eco-dishwashing program, a so-called auto-dishwashing program, in which in particular the degree of soiling of the dishwashing liquid when rinsing the dishes to be cleaned is determined preferably by means of at least one sensor such as a turbidity sensor and is used for the automatic setting of at least one rinsing parameter and/or drying parameter, a quick program, an intensive cleaning program (in particular with an increased temperature during its cleaning phase), a night-time cleaning program, a special program for washing glasses, etc., which differ from one another in that their regeneration phases have different lengths, the control logic assigns different delivery volume flows or throughput rates, i.e. flow volume per time, of the dishwashing chamber air conveyed by the air conveying unit during these regeneration phases, to these different lengths of regeneration time of the regeneration phases. In a corresponding manner, the control logic adjusts the volume flow of the wash cabinet air conveyed by the air conveying unit for the regeneration phase if the respective selected dishwashing program exceeds the duration of its regeneration phase changed, i.e. extended or shortened. For example, the dishwashing program currently being carried out can shorten its regeneration phase if, during the previous dishwashing program, the dishwasher's wash cabinet was only partially loaded with dishes, so that after the last partial wash phase of this previous dishwashing program, the sorption material of the sorption drying system had to absorb a smaller total amount of water during its drying phase than when the wash cabinet was fully loaded. Through this individual or specific adaptation of the conveying volume flow of the wash cabinet air conveyed by the air conveying unit during the respectively specified regeneration period of the respective dishwashing program, the sorption material of the fixed bed can be regenerated in a more energy-saving or energy-efficient manner than if the air conveying unit were to convey the wash cabinet air with one and the same, i.e. always the same, conveying volume flow value for the different regeneration phases of the various dishwashing programs.

When carrying out different dishwashing programs, the household dishwasher according to the invention preferably switches to different desorption operating modes for the respective regeneration of the sorption material of the fixed bed:
The various dishwashing programs differ from one another in terms of the different lengths of their regeneration phases and the specifically assigned, different inlet temperatures of the dishwashing chamber air heated by the desorption heating device. During the different lengths of the regeneration phases of the various dishwashing programs, the air is conveyed into the fixed bed via its inlet cross-sectional area by means of the switched-on air conveying unit and flows through the fixed bed along its bed height in the flow direction. These different inlet temperatures of the air flowing into the inlet cross-sectional area of the fixed bed, which are assigned to the different lengths of the regeneration phases of the various dishwashing programs, are accompanied by different local regeneration temperature profiles in the sorption material of the fixed bed across its bed height in the flow direction, which at a fixed or constant thermal (output) heating power of the heating device provided for desorption can be achieved by different volumetric flows of the air conveying unit. The electrical energy consumption of the desorption heating device, which provides a fixed, i.e. constant, heating power in relation to the respective dishwashing program to be carried out, is largely determined by the heating time during which it is in operation during the regeneration phase of the respective dishwashing program. The shorter the duration of the regeneration phase of the respective dishwashing program to be carried out, the shorter the heating time of the desorption heating device and thus its electrical energy consumption when regenerating the sorption material. This is because the heating time preferably corresponds to the duration of the regeneration phase. If necessary, it can even be shorter than this. For example, to save energy, the heating time can be shortened compared to the duration of the regeneration phase towards the end of the regeneration phase by a remaining time that is fixed for all dishwashing programs, i.e., always the same, during which the desorption heating device is already switched off and only wash cabinet air is circulated through the recirculation duct of the sorption drying system by means of the air conveying unit. During this remaining time, which is fixed for all dishwashing programs, the sensible heat previously stored in the sorption material is sufficient to continue desorbing the sorption material. In this way, the control/monitoring unit of the household dishwasher according to the invention provides dishwashing programs with regeneration phases that vary in energy consumption.

An electric heater, particularly an air heater, with a fixed or constant (output) heating output is preferably sufficient as the desorption heating device for desorbing the sorption material. This heater heats the washroom air, which is forced through the recirculation duct by the air conveying unit, before it enters the fixed bed, as viewed in the direction of flow. A more complex and controllable electric heater with regard to its thermal output is therefore not required for desorbing the sorption material.

By controlling the air delivery unit’s flow rate from the control logic in relation to the If the respective predefined regeneration time period of the regeneration phase of the respective dishwashing program is specifically set, the regeneration temperature achieved in the sorption material can be varied in specific dependence on the respective predefined regeneration time period or target regeneration time period of the regeneration phase of the respective dishwashing program, with a fixed or constant heating output of the heating device provided for the desorption of the sorption material, which delivers this to the air forcibly conveyed by the air conveying unit during the regeneration phase of the respective dishwashing program. The conveyed volume flow indicates the volume of air that is moved, i.e. transported, by the air conveying unit through the recirculation duct and thus through the fixed bed of loose, granular or granular, reversibly dehydratable sorption material per period of time.

According to an advantageous development of the invention, the air conveying unit is a fan or blower, the speed of which the control logic adjusts specifically depending on the respective predetermined duration of the regeneration phase of the respective dishwashing program. The control logic adjusts the speed of the impeller of the fan or blower individually for the respective predetermined regeneration period of the regeneration phase of the respective dishwashing program such that the conveying volume flow of the forced-conveyed air generated by the fan during the respective regeneration period of the regeneration phase of the respective dishwashing program, which is at least temporarily subjected to the fixed or constant heating power of the desorption heating device during the respective regeneration period of the regeneration phase of the respective dishwashing program, effects a regeneration temperature in the fixed bed of the sorption material that is specifically tailored to the respective regeneration period of the regeneration phase of the respective dishwashing program. If several dishwashing programs are provided, which differ from one another in the length of their regeneration phases, the control logic assigns different volumetric flow rates of the wash cabinet air to these programs, which are generated by different fan speeds. With regard to a single dishwashing program, in which the duration of its regeneration period is varied, this changed period is adjusted in an analogous manner. The control logic specifically assigns a changed volume flow of the wash cabinet air based on a correspondingly changed speed of the fan.

When carrying out the regeneration phases of different lengths of the various dishwashing programs provided by the control/monitoring unit or a dishwashing program to be carried out, the control logic does not simply set the conveying volume flow of the air conveying unit to a fixed value in such a way that the same target regeneration temperature equal to or above a limit temperature is always achieved for the regeneration of the loose sorption material of the fixed bed, which leads to the extensive or almost complete expulsion of the water bound in the sorption material, but now makes a distinction as to how high the regeneration temperature achieved in the sorption material should be in specific dependence on the respectively specified regeneration time duration of the regeneration phase of the respective dishwashing program. For the different lengths of the regeneration phases of the various dishwashing programs or of the respective dishwashing program, the control logic is therefore not based on always achieving the same target regeneration temperature equal to or above a limit temperature that leads to the extensive or almost complete expulsion of the water bound in the sorption material by the end of the regeneration phase of the respective dishwashing program. Instead, the control logic changes the conveying volume flow of the air conveying unit and, with a fixed or constant heating output of the desorption heating device provided for desorption, the regeneration temperature achieved in the sorption material in a specific or individual manner depending on the length or duration of the regeneration phase of the respective dishwashing program. In an advantageous manner, the thermal energy expenditure for the regeneration of the sorption material can thus be specifically or individually adapted to the respective regeneration time duration of the regeneration phase of the respective dishwashing program.

In particular, the control logic can adjust the flow rate of the air conveying unit for the regeneration phase of at least one energy-saving dishwashing program to be carried out in such a way that the regeneration temperature achieved in the sorption material is lower or lower than the limit regeneration temperature from which the sorption material would largely or almost entirely desorb the water adsorbed by it during the sorption drying phase of a preceding dishwashing program. By deliberately lowering the regeneration temperature below the limit regeneration temperature, from which the sorption material would desorb almost all of the water adsorbed by it during the drying phase of a previous dishwashing program, during the specified duration of the regeneration phase of the energy-saving dishwashing program currently being carried out, the amount of water stored in the sorption material during the sorption drying phase of the previous dishwashing program is not desorbed completely, but only predominantly until a desired minimum residual moisture amount or target residual moisture amount of water remains (which is greater than the minimum remaining residual moisture in the sorption material when desorbing at the limit regeneration temperature), which is more energy efficient, i.e. requires less thermal energy, than if the sorption material were heated at least to the limit regeneration temperature, from which the sorption material would desorb almost all of the water it has adsorbed.

Advantageously, the control/monitoring unit of the household dishwasher according to the invention thus provides, in particular, at least one energy-saving dishwashing program, during the execution of which the household dishwasher according to the invention is operated in a more energy-efficient operating mode than in other dishwashing programs provided by its control/monitoring unit. In this energy-saving dishwashing program, the control logic preferably changes the conveying volume flow of the air conveying unit for the regeneration phase such that the regeneration temperature brought about in the sorption material is lower than the minimum regeneration temperature limit required for almost complete desorption, so that a desired minimum residual moisture or target residual moisture content of water remains adsorbed by the sorption material, which is now deliberately increased compared to the minimum residual moisture amount adsorbed by the sorption material at the regeneration temperature limit. The expulsion of this increased minimum residual moisture from the sorption material would require a disproportionately high expenditure of thermal energy, which would be provided by the desorption heating device by A corresponding amount of electrical energy would be required to convert it into thermal energy.

To regenerate the sorption material, the desorption heating device heats the wash chamber air, which is forced onto the sorption material by the air conveying unit, during the regeneration phase using electrical energy. The air conveying unit running during the regeneration phase allows only a portion of the thermal energy generated by the desorption heating device to be introduced into the wash chamber of the domestic dishwasher's washing container during at least one wash phase, in particular the cleaning phase, of the wash program following the sorption drying cycle of the respective wash program being performed, and to contribute to heating the wash chamber or the wash liquid introduced there. This is because the total heat energy originally generated to desorb the sorption material by the desorption heating device is reduced by the thermal dissolution energy required to overcome the adsorption binding forces, by the sensible heat absorbed by the sorption material until the target regeneration temperature is reached, and by the waste heat losses of the heated sorption material to the environment. If the sorption container with the fixed bed is housed in a floor assembly of the household dishwasher below its wash tub, waste heat from the fixed bed of sorption material is lost to the walls of the sorption container and from there to the air present in the floor assembly and to neighboring components of the floor assembly. The lower the target regeneration temperature is set, the lower the thermal dissolution energy that is consumed for the dissolution of adsorption bonds between the sorption material and the water molecules captured by it during the sorption drying cycle of the preceding dishwashing program, the lower the sensible heat stored by the sorption material, and the lower the waste heat losses of the heated sorption material to the environment due to the smaller temperature gradient between the temperature of the sorption material of the fixed bed and the temperature of the environment outside the fixed bed.

According to an advantageous development of the invention, the control/monitoring unit of the household dishwasher according to the invention provides several Dishwashing programs are available with different regeneration phases. For example, an intensive cleaning program can have a regeneration time of 20-35 minutes for desorbing the sorption material, while an energy-saving dishwashing program that meets an energy label A of the energy consumption classification scheme valid in the EU from March 1, 2021, can have a shorter regeneration time of 5-15 minutes.

It may be particularly advantageous if the desorption heating device intended for regenerating the sorption material is designed as an electric air heater, which is provided in the recirculating air duct upstream of the fixed bed of sorption material housed in the sorption container, as viewed in the direction of forced air flow. Because the air flowing through the fixed bed of loose, granular, or reversibly dehydratable sorption material is heated upstream of the fixed bed by the electric air heater before entering the fixed bed, it is largely ensured that the air flows into the fixed bed at a defined heating temperature. Since the heated air flows through the spaces between the loose grains or granulate particles of the sorption material accommodated as a fixed bed in the sorption container, thermal energy or heat energy can be supplied to the grains or granules of the sorption material in a largely uniform manner and can be released to them in a largely uniform manner.

According to an advantageous development of the invention, the control logic which sets the conveying volume flow of the air conveying unit for the regeneration phase of the respective dishwashing program is a component of the control/monitoring unit which is provided for the execution of the one or more dishwashing programs. The control/monitoring unit and/or the control logic are preferably implemented by one or more hardware components, which in particular comprise a microcomputer system with an electronic storage system, and/or by software components which are stored in at least one electronic memory of a computer, in particular a microcomputer system, of the household dishwasher according to the invention, and which control the sequence procedure, i.e. sequence of one or more rinsing steps or rinsing phases and the final drying step of the respective Dishwashing program. In particular, the control logic can be a program part or a subroutine of the sequence procedure of the respective dishwashing program to be executed.

According to a further advantageous development of the invention, the control/monitoring unit provides at least one energy-saving dishwashing program, during the execution of which by the control/monitoring unit, the control logic shortens the duration of the regeneration phase compared to the duration of the regeneration phase of at least one other selectable dishwashing program and simultaneously increases the conveying volume flow of the air conveying unit during the regeneration phase of the energy-saving dishwashing program compared to the conveying volume flow of the air conveying unit specifically assigned to the other dishwashing program. As a result, during the energy-saving dishwashing program, the regeneration temperature induced in the sorption material is reduced to a reduction regeneration temperature that is lower than the regeneration temperature induced in the other selectable dishwashing program. The reduction regeneration temperature is in particular lower than the limit regeneration temperature above which the sorption material would almost completely desorb all of the water adsorbed by it during the drying phase of the preceding dishwashing program during the predetermined regeneration period. The limit regeneration temperature for zeolite(s), especially zeolite(s) of type A, type Y, and/or type 13X, as sorption material is approximately 280° C (Celsius).

According to an advantageous development of the invention, it is advantageous if the control logic, when carrying out the energy-saving dishwashing program, shortens the duration of the regeneration phase compared to the duration of the regeneration phase of the other selectable dishwashing program to a short regeneration period and simultaneously increases the conveying volume flow of the air conveying unit during the regeneration phase of the energy-saving dishwashing program compared to the conveying volume flow of the air conveying unit specifically assigned to the regeneration phase of the other dishwashing program in such a way that the regeneration temperature caused in the flow inlet side region of the fixed bed in the sorption material is reduced to a reduction regeneration temperature which is lower than the regeneration temperature brought about in the sorption material in the flow inlet-side region of the fixed bed in the other selectable dishwashing program, and the regeneration temperature brought about in the sorption material in a fluidically downstream region of the fixed bed, in particular the region associated with the air outlet or flow outlet of the fixed bed, is increased to an increase regeneration temperature which is greater than the regeneration temperature brought about in the sorption material in the fluidically downstream region of the fixed bed, in particular the region associated with the air outlet or flow outlet of the fixed bed, in the other selectable dishwashing program. If the inlet temperature of the air stream conveyed into the fixed bed is lowered—in particular by increasing the speed of the air conveying unit, which is preferably designed as a fan—a somewhat smaller amount of water is expelled from the sorption material SM along a first inlet-side section of the fixed bed. However, the expulsion of water from the sorption material in the subsequent section of the fixed bed, particularly the outlet-side section, is now more successful than in the case of an air stream with a higher inlet temperature. By lowering the inlet temperature of the air stream, the detachment of adsorbed water is specifically limited to those adsorption loading sites or binding sites of the sorption material with weaker adsorption binding energies. As a result, during the specified regeneration period, there is no premature and excessive extraction and consumption of heat energy from the air stream heated by the desorption heating device along a section of the fixed bed inlet viewed in the direction of flow, by adsorption loading sites of the sorption material, which require overcoming higher adsorption binding energies to release the water molecules bound to them. In this way, the heat front of the air stream flowing into the fixed bed advances further along the extension of the fixed bed at approximately the level of its inlet temperature and, compared to this level of the inlet temperature, drops less or not at all along the further extension of the fixed bed up to its flow outlet (compared to an air flow with a higher inlet temperature). In other words, this means that the particles or grains of the The sorption material is now heated to a higher temperature, so that more water molecules are released from its adsorption loading sites (than with an air flow with a higher inlet temperature). This ensures more uniform heating of the sorption material and thus more uniform desorption of the sorption material across the entire extent of the fixed bed in the flow direction, with an overall lower expenditure of thermal energy or, correspondingly, electrical energy from the desorption heating device.

In particular, given this behavior of the fixed bed, it may be advantageous to set the inlet temperature of the wash cabinet air conveyed into the fixed bed (by correspondingly increasing the air flow rate of the air conveying unit) lower the shorter the duration of the regeneration phase of the respective dishwashing program, especially the energy-saving dishwashing program. The shorter the duration of the regeneration phase with a fixed heating output of the desorption heating device, the lower the thermal energy required to be provided by the desorption heating device.

In particular, it may be expedient - preferably with regard to the sorption materials specified above - if the control logic sets the short regeneration period for the regeneration phase of the energy-saving dishwashing program to be less than or equal to 15 minutes, in particular between 5 minutes and 15 minutes, and simultaneously or additionally increases the conveying volume flow of the air conveying unit during the regeneration phase of the energy-saving dishwashing program in such a way that during this short regeneration period of the regeneration phase, in the flow inlet-side region of the fixed bed in the sorption material, a reduction regeneration temperature (lower than the limit regeneration temperature) of at least 120°C and at most 200°C, in particular of at least 120°C and at most 150°C, is effected. This leads to an energetically optimized regeneration of the sorption material during the energy-saving dishwashing program with regard to the amount of water expelled.

It may be advantageous, in particular, to use the desorption heating device with the same or constant electrical power and the associated constant thermal output for the different lengths of regeneration phases of different dishwashing programs, but to reduce the running time of its regeneration phase for at least one more energy-efficient dishwashing program, in particular an energy-saving dishwashing program, compared to the running times of the regeneration phases of one or more other, less energy-efficient dishwashing programs. Surprisingly, it has been shown that in order to desorb the amount of water stored in the sorption material during the sorption drying phase of the preceding dishwashing program, it is not necessary to increase the regeneration temperature (by increasing the thermal heating power of the desorption heating device, which requires a corresponding increase in the electrical consumption of the desorption heating device) for the implementation of the regeneration phase of the energy-saving dishwashing program in order to be able to introduce approximately the same amount of thermal energy into the sorption material with a shortened regeneration period as previously with longer regeneration periods. Instead, a regeneration temperature that is reduced or lower than the regeneration temperatures of one or more other, less energy-efficient dishwashing programs, in particular between 120°C and a maximum of 200°C, in particular between 120°C and a maximum of 150°C, preferably for the zeolite types specified above, is sufficient for the implementation of the regeneration phase of the energy-saving dishwashing program in order to To be able to expel a sufficient portion of the water adsorbed during the sorption drying cycle of the preceding dishwashing program to dry the wash ware from the sorption material down to a minimum residual moisture content, which is now deliberately increased compared to the minimum residual moisture content adsorbed by the sorption material at the limit regeneration temperature. This desired reduction in the regeneration temperature in the sorption material of the fixed bed during the shortened regeneration phase of the energy-saving dishwashing program is achieved by the air conveying unit correspondingly increasing the volume flow of the wash chamber air through the fixed bed.

In an advantageous manner, the control/monitoring unit therefore provides, when viewed in summary, at least one energy-saving dishwashing program, during the execution of which the control logic operates the air conveying unit with a modified conveying volume flow in order to reduce the regeneration temperature achieved in the sorption material during the regeneration phase, which is higher than the conveying volume flow of the air conveying unit during the regeneration phases of the one or more other, less energy-efficient dishwashing programs.

Preferably, a fan or blower is provided as the air conveying unit. By increasing the fan speed, the regeneration temperature in the sorption material can be reduced. This temperature is caused by the forced-feed washroom air heated by the desorption heating device.

In particular, it is advantageous if the fixed bed is accommodated and aligned in the sorption container in such a way that the forced air flow generated by the air conveying unit during the regeneration phase and drying phase of the respective dishwashing program flows through it in a vertical direction against the direction of gravity. This largely ensures that the fixed bed, viewed over its vertical extent, has a passage cross-sectional area uniformly or homogeneously occupied by the sorption material at every height point and permanently maintains this cross-sectional area over the entire operating life of the household dishwasher. The fixed bed is preferably formed by a bed of loose grains or granulate pieces of a sorption material, which is held in particular between a lower sieve grid and an upper sieve grid. In particular, the loose grains or granulate pieces of the sorption material are spherical.

According to an advantageous development of the invention, the control/monitoring unit provides at least one energy-saving dishwashing program, during the execution of which the control logic for reducing the inlet temperature of the dishwashing chamber air heated by means of the desorption heating device, which is conveyed into the fixed bed during the regeneration phase of the energy-saving dishwashing program by means of the air conveying unit, and thus the regeneration temperature brought about in the sorption material during the regeneration phase, the conveying volume flow of the air conveying unit in such a way (in comparison to one or more less energy-efficient, other dishwashing programs) increases that the sorption material of the fixed bed is only brought to a regeneration temperature during the respective specified regeneration period of the regeneration phase at which a specifically increased minimum residual moisture content of between 5% and 15%, in particular between about 10% and 15%, based on the dry mass of the sorption material remains in it. (For example, in the case of zeolite(s) of type A, Y and/or 13X, this preferably requires a regeneration temperature between 120° C and 200° C, preferably between 150° C and 170° C, with a regeneration time of between 5 and 15 minutes.) In this way, the control logic ensures that the regeneration temperature brought about in the sorption material during the respective specified duration of the regeneration phase only releases water from those adsorption binding sites of the sorption material that require a lower average regeneration energy compared to those adsorption binding sites of the sorption material for which a disproportionately higher regeneration energy per adsorption volume, i.e. volume of adsorbed water per dry mass of sorption material, is required. By deliberately lowering the resulting regeneration temperature (compared to the limit regeneration temperature), regeneration is limited to the removal of adsorbed water only from the adsorption loading sites of the sorption material with lower adsorption binding energy. The adsorption loading sites of the sorption material with higher adsorption binding energy, however, are deliberately no longer used. This improves the energy efficiency during desorption or regeneration.

The above regeneration strategies are pursued by the advantageously designed household dishwashers of claims 9 and/or 10:
These regeneration strategies each save thermal energy during regeneration, which reduces the total energy consumption per energy-saving dishwashing program compared to other dishwashing programs in which the sorption material is brought to at least the limit regeneration temperature during the respective specified regeneration period of the regeneration phase, from which the sorption material almost or almost completely absorbs all of the water adsorbed by it during the drying phase of a previous dishwashing program. would desorb completely. Since those adsorption bonds which bind water molecules disproportionately more strongly than the other adsorption bonds of the sorption material are responsible for a residual moisture content of between 5% and 15% in the sorption material, in particular zeolite material, preferably of type A, type Y, and/or type 13X, by not dissolving, i.e. maintaining these strong adsorption bonds, a disproportionately high thermal energy expenditure required for their dissolution and, associated with this, a correspondingly disproportionately high amount of electrical energy for operating the desorption heating device, in particular electrical desorption heating device, can be saved. The targeted restriction of the regeneration to these weaker adsorption binding sites means that the expenditure of thermal regeneration energy required for this is preferably between 10% and 30% lower than the total expenditure of thermal regeneration energy that would be required for the complete desorption of the water molecules from all, i.e. weak and strong adsorption binding sites, and nevertheless the amount of water expelled from the sorption material from the adsorption binding sites with weak binding energy is sufficiently large so that the sorption material is sufficiently desorbed for the drying phase that concludes the wash program in order to be able to adsorb the amount of moisture present on the washware items after the last liquid-carrying partial wash phase, in particular the final rinse phase, by the warm, moist washroom air that is forcibly conveyed through the fixed bed of the sorption material by means of the air conveying unit. In particular, the amount of water that can be expelled from the sorption material from the adsorption binding sites with weak binding energy corresponds to between 40% and 80% of the total amount of water that can be expelled with almost complete desorption.

Furthermore, the invention also relates to a method according to claim 12.

Further developments of the invention are set forth in the subclaims. The advantageous embodiments and/or developments of the invention explained above and/or set forth in the subclaims can be applied individually or in any combination with one another - except, for example, in cases of clear dependencies or incompatible alternatives.

The invention and its advantageous developments and/or further developments as well as their advantages are explained in more detail below using drawings.

Figur 1

in schematischer Darstellung ein vorteilhaftes Ausführungsbeispiel einer erfindungsgemäß ausgebildeten Haushaltsgeschirrspülmaschine mit einem Sorptionstrocknungssystem, dessen Sorptionsmaterial bei der Durchführung ein oder mehrerer Geschirrspülprogramme, insbesondere mindestens eines Energiespar- Geschirrspülprogramms, nach dem erfindungsgemäßen Prinzip regeneriert wird,

Figur 2

in schematischer Darstellung eine charakteristische Kurve vorzugsweise für Zeolith(en) vom Typ A, Typ Y und/oder Typ 13X als Sorptionsmaterial, welche die Regenerationsenergie angibt, die pro Adsorptionsvolumen, d.h. Volumen an adsorbiertem Wasser pro Sorptionsmaterialtrockenmasse, zum Lösen von Wasser von den Adsorptionsbindungsplätzen des Sorptionsmaterials aufzuwenden ist, sowie einen vorteilhaften Arbeitsbereich unterhalb dieser charakteristischen Kurve, der für den erfindungsgemäßen Regenerationsbetrieb mindestens eines Geschirrspülprogramms, insbesondere Energiespar- Geschirrspülprogramms der Haushaltsgeschirrspülmaschine von Figur 1 nutzbar ist,

Figur 3

in schematischer Darstellung über die Durchströmungserstreckung, insbesondere Höhenerstreckung, einer Festbettschüttung losen Sorptionsmaterials betrachtet, welche in einem Sorptionsbehälter des Sorptionstrocknungssystems der Haushaltsgeschirrspülmaschine von Figur 1 untergebracht ist, die örtlichen Verläufe der im Sorptionsmaterial bewirkten Regenerationstemperaturen bei derselben vorgegebenen Regenerationszeitdauer für zwei unterschiedlich hohe Eintrittstemperaturen eines Spülraumluftstroms, der mittels einer Luftfördereinheit des Sorptionstrocknungssystems aus dem Spülraum der Haushaltgeschirrspülmaschine von Figur 1 heraus in den Umluftkanal dessen Sorptionstrocknungssystems hineingefördert und durch die Festbettschüttung des losen Sorptionsmaterials zwangsweise hindurchgefördert wird sowie vor seinem Einströmen in die Festbettschüttung mittels einer Desorptions-Heizungsvorrichtung aufgeheizt wird, und

Figur 4

in schematischer Darstellung die verschiedenen Phasen eines erfindungsgemäßen Energiespar- Geschirrspülprogramms der Haushaltsgeschirrspülmaschine von Figur 1, bei welchem im Vergleich zu einem anderen auswählbaren, weniger energieeffizienten Geschirrspülprogramm die Zeitdauer seiner Regenerationsphase verkürzt und gleichzeitig bzw. zusätzlich die im Sorptionsmaterial bewirkte Regenerationstemperatur durch Erhöhung des Fördervolumenstroms der in die Festbettschüttung hineingeförderten Spülraumluft herabgesetzt ist.

They show, in a schematic principle sketch:

Figure 1

in schematic representation an advantageous embodiment of a household dishwasher designed according to the invention with a sorption drying system, the sorption material of which is regenerated according to the principle of the invention when carrying out one or more dishwashing programs, in particular at least one energy-saving dishwashing program,

Figure 2

in schematic representation a characteristic curve preferably for zeolite(s) of type A, type Y and/or type 13X as sorption material, which indicates the regeneration energy which is to be expended per adsorption volume, ie volume of adsorbed water per sorption material dry mass, for releasing water from the adsorption binding sites of the sorption material, as well as an advantageous working range below this characteristic curve which is suitable for the inventive regeneration operation of at least one dishwashing program, in particular energy-saving dishwashing program of the household dishwasher of Figure 1 is usable,

Figure 3

in a schematic representation of the flow extension, in particular height extension, of a fixed bed of loose sorption material, which is in a sorption container of the sorption drying system of the household dishwasher of Figure 1 is housed, the local courses of the regeneration temperatures induced in the sorption material at the same specified regeneration time for two different inlet temperatures of a wash cabinet air flow, which is drawn by means of an air conveying unit of the sorption drying system from the wash cabinet of the household dishwasher of Figure 1 out into the recirculation duct of its sorption drying system and is forced through the fixed bed of loose sorption material and its flow into the fixed bed is heated by means of a desorption heating device, and

Figure 4

in schematic representation the different phases of an energy-saving dishwashing program according to the invention of the household dishwasher of Figure 1 in which, in comparison to another selectable, less energy-efficient dishwashing program, the duration of its regeneration phase is shortened and, at the same time or additionally, the regeneration temperature caused in the sorption material is reduced by increasing the volume flow of the dishwashing chamber air conveyed into the fixed bed.

Elements with the same function and mode of operation are provided with the same reference symbols in the figures.

Figure 1 shows a schematic representation of an exemplary household dishwasher GS with a sorption drying system SY, whose sorption material is regenerated according to the inventive principle during the execution of one or more dishwashing programs, in particular at least one energy-saving dishwashing program. Figure 1 Only those components of the GS household dishwasher that are necessary for understanding the invention are provided with reference numerals and explained. It goes without saying that the GS household dishwasher may include additional parts and assemblies.

The domestic dishwasher GS has a wash chamber SR for accommodating items to be cleaned. The wash chamber SR is delimited by the walls of an approximately cuboid-shaped wash tub SB and a door, in particular a front door, which closes the loading opening, in particular the front-facing one. This is shown in the schematic front view of the Figure 1 omitted for the sake of simplicity of the drawing. The boundary walls of the washing container SB are for an operator standing in front of the household dishwasher GS for its intended use, in particular a left-hand side wall, a right-hand side wall, a top wall, a Floor wall and a rear wall. In the wash cabinet SR, one or more storage units are provided for the items to be cleaned, in particular a lower crockery basket, an upper crockery basket, and/or a cutlery drawer, preferably arranged above the upper crockery basket. The latter is not shown in the drawing for the sake of clarity or for reasons of space. Figure 1 omitted. To apply washing liquid to the items placed in the receiving units, one or more spray devices or other liquid distribution devices are provided in the wash cabinet SR. These can be, in particular, rotatable spray arms, an upper roof spray, and/or other liquid application devices, such as spray units specially attached to one or more dish baskets. Figure 1 In the washing chamber SR, a lower and an upper rotatable spray arm SV are shown as representative of the liquid application means, as well as a lower dish basket UB and an upper dish basket OB as representative of the storage units for the items to be cleaned. For the respective washing operation of the household dishwasher during one or more different washing phases of the respective dishwashing program, washing liquid is supplied by means of a Figure 1 The water inlet system (omitted for simplicity of the drawing) is let into the wash chamber SR. The wash liquid is pumped by means of a circulating pump UP via one or more liquid lines VL to the spray devices or liquid distribution devices such as SV and from there sprayed onto the items to be cleaned in the holding units. The wash liquid drips to the floor and collects in a pump sump or pump pot PS, which is provided below the bottom wall of the wash container SB. The circulating pump UP sucks the wash liquid from the pump sump PS, preferably via an intake nozzle, and pumps it to the spray devices or liquid distribution devices such as SV via the one or more liquid lines VL. In this way, a liquid circulation circuit is provided. This can preferably comprise further components, such as a water switch for the selective control of the respective liquid line, which leads separately to the respective spray device or liquid distribution device. In the liquid circulation circuit, a liquid heater or water heater WH is also provided in particular in order to heat the rinsing liquid to a desired heating temperature or target heating temperature if required. Here in the Example of Figure 1 The liquid heater WH is preferably assigned to the circulation pump UP. In particular, the liquid heater is housed within the circulation pump, i.e., the circulation pump UP is preferably designed as a heating pump.

The sorption drying system SY has a recirculating air duct UK located outside the wash cabinet SR. This recirculating air duct ÙK fluidically connects an air outlet AL of the wash cabinet SR with an air inlet EL of the wash cabinet SR. For example, the air outlet AL can be a through-opening in a side wall - as shown here in the exemplary embodiment of Figure 1 viewed from the front in the right-hand side wall - of the washing container SB and as an air inlet EL a through opening preferably in a different boundary wall of the washing chamber SR - here in the embodiment of Figure 1 in the bottom wall of the rinsing tank SB. A sorption tank SOB is fluidically inserted into the recirculating air duct UK. It contains a fixed bed FS of a loose, granular or granular, reversibly dehydratable sorption material SM. This can preferably be spherical. The bed of loose grains and/or granular pieces of the sorption material is preferably held between a lower sieve grid US and an upper sieve grid OS of the fixed bed FS. Viewed in the vertical direction, the bed has a predetermined maximum or upper bed height SH. The fixed bed FS of the sorption material SM is accommodated in the sorption tank SOB in such a way that it can be flowed through by a forced air flow, which can be generated by means of an air conveying unit LF fluidically inserted into the recirculating air duct (UK), from bottom to top, in particular essentially in a vertical direction against the direction of gravity. This largely ensures that the fixed bed FS, viewed over its height up to its specified maximum bed height SH, has a largely uniform or homogeneous cross-sectional area filled with the loose sorption material SM at each height point HS, and that this distribution of the loose sorption material SM is maintained permanently over the operating life of the domestic dishwasher GS. A first air duct section LK1 of the recirculation duct UK runs between the air outlet AL of the wash cabinet SR and the air inlet EI of the sorption container SOB. The air conveying unit LF is preferably fluidically inserted into this. The air conveying unit LF is thus viewed in the flow direction of the wash cabinet air forced through it preferably fluidically inserted between the air outlet AL of the wash cabinet SR and the air inlet EI of the sorption container SOB in front of the sorption container SOB into the recirculating air duct ÙK. The air conveying unit LF is expediently formed by a fan or blower. When the air conveying unit LF is in operation, i.e. switched on, it draws wash cabinet air from the wash cabinet SR to itself via the upstream section of the first air duct section LK1 and then actively blows this air to the sorption container SOB and into it via the downstream section of the first air duct section LK1. It blows the washroom air through the air inlet EI of the sorption tank SB through the fixed bed of loose, granular, or reversibly dehydratable sorption material SM from bottom to top, in particular essentially in a vertical direction against the direction of gravity. The washroom air forced through the fixed bed FS leaves the sorption tank SOB via an air outlet AU and is either directly or, as in this embodiment, by Figure 1 via a second air duct section LK2 of the recirculation duct UK into the air inlet EL of the wash chamber SR. If the air conveying unit LF is switched on, it draws air from the wash chamber SR via its air outlet AL into the recirculation duct UK and then blows this air through the fixed bed of loose, granular, or granular, reversibly dehydratable sorption material SM of the sorption container SOB and then back into the wash chamber SR via the air inlet EL. In this way, air from the wash chamber (i.e., wash chamber air) circulates via the recirculation duct UK to the sorption container SOB fluidically inserted in the recirculation duct UK and from there back into the wash chamber SR when the air conveying unit LF is switched on. The forced air flow generated in this way during operation of the air conveying unit LF through the recirculation duct UK, through the fixed bed of loose sorption material SM and through the wash chamber SR is in the Figure 1 indicated by direction arrows ZLS.

The household dishwasher GS comprises a control/monitoring unit CO for carrying out one or more dishwashing programs. Each dishwashing program comprises one or more rinsing phases, during which the items to be cleaned in the washing chamber are sprayed with rinsing liquid by means of one or more spray devices or liquid distribution devices, and a drying phase concluding the washing program. It preferably comprises, in chronological succession, a pre-rinse phase, a cleaning phase, a Intermediate rinsing phase and a final rinsing phase as liquid-carrying rinsing phases or rinsing steps. Figure 4 illustrates the temporal sequence of these dishwashing phases, namely the pre-wash phase VP, the cleaning phase RP, the intermediate rinse phase ZP and the final rinse phase KP, and the drying phase TP at the end of the dishwashing program, each for two different dishwashing programs GP, EP, in detail. The time t in seconds (abbreviated to sec) is plotted along the abscissa, and the temperature SRT in degrees Celsius (abbreviated to °C) of the temperature in the dishwashing cabinet SR is plotted along the ordinate, which corresponds to the temperature of the respective dishwashing liquid and/or air temperature in the dishwashing cabinet SR. The dishwashing cabinet temperature curve for the energy-saving dishwashing program EP is designated TSR, and the dishwashing cabinet temperature curve for the dishwashing program GP is designated TSR'. The temperature curve TSR' of the dishwashing program GP deviates from the temperature curve TSR of the energy-saving dishwashing program EP during the cleaning phase RP. To indicate this, the section of the temperature curve TSR' assigned to the cleaning phase RP is shown in dash-dotted lines. Otherwise, the remaining sections VP, ZP, KP, TP of the two temperature curves TSR, TSR' correspond approximately to one another in this exemplary embodiment for the sake of simplicity. Firstly, for the respective dishwashing program EP or GP, from time tVS onwards, fresh water at tap temperature from a fresh water supply line and/or preferably fresh water stored in a storage reservoir and/or service water at approximately room temperature UT is admitted into the wash chamber SR for the pre-wash phase VP by means of the water inlet system (not shown) of the household dishwasher GS. During this pre-wash step, the running circulating pump UP pumps the liquid to the spray devices or liquid distribution devices such as SV, from which it is sprayed onto the items to be cleaned or applied in some other way. Towards the end of the pre-wash phase VP, some or all of the wash liquid is pumped out. For this purpose, a drain pump is preferably provided, which is located in the Figure 1 has been omitted for the sake of simplicity. The drain pump partially or completely pumps the washing liquid out of the pump sump PS and conveys it out of the household dishwasher GS via a drain line. The pre-wash step VP ends in the embodiment of Figure 4 at time tVE. From the start time tRS (= tVE) of the subsequent cleaning phase RP, fresh water from the fresh water supply line, and/or fresh water and/or process water stored in a storage reservoir is admitted into the wash chamber SR for the cleaning phase RP and heated during the preferably predetermined duration tHE - tRS or tHE' - tRS of an initial heating phase HP or HP' to a required maximum cleaning temperature or target cleaning temperature RT or RT' up to the time tHE or tHE'. Preferably, even during the water inlet and heating up, the wash liquid for the cleaning step or the cleaning phase RP is circulated in the liquid circulation circuit by means of the circulation pump UP and sprayed onto the items to be cleaned by means of its spray devices or liquid application devices such as SV. Detergent is preferably added to the wash liquid for the cleaning phase RP. Once the required cleaning temperature RT or RT' has been reached at the time tHE or tHE', the heating of the wash liquid is stopped. This is followed by a so-called post-wash phase NWP or NWP', during which the rinsing liquid is only circulated in the liquid circuit by means of the running circulation pump UP and applied to the items to be cleaned by means of the spray devices or liquid application devices SV, but is no longer actively heated by either the desorption heating device HV or the rinsing liquid heater WH. Shortly before the end of the cleaning step RP at time tRA, the cleaning liquid is partially or completely pumped out of the wash cabinet SR by means of the drain pump (not shown). Then, at time tZS (= tRA), fresh water from the fresh water line and/or fresh water stored in the storage reservoir and/or process water for a subsequent intermediate rinsing step ZP is admitted into the wash cabinet SR via the water inlet system. This rinsing liquid is then distributed in the wash cabinet SR by means of the spray devices or liquid distribution devices such as SV. During this intermediate rinse phase ZP, the water heater WH usually remains switched off. At the end of the intermediate rinse phase ZP at time tZE, the rinse liquid used for the intermediate rinse is again partially or completely pumped out of the wash chamber SR by the drain pump. Afterwards, for the final rinse phase KP, which follows at time tKS (= tZE), fresh water from the fresh water line and/or fresh water and/or service water from the storage reservoir is again admitted into the wash chamber SR via the water inlet system. This fresh water and/or service water for the Rinse aid is preferably added to the final rinse. The rinse liquid mixed with rinse aid is distributed by the circulation pump UP via the supply lines VL to the spray devices or liquid distribution devices or liquid application devices such as SV and applied to the items to be cleaned in circulation mode. During the final rinse phase KP, the rinse liquid can, if necessary, be heated to a required maximum rinse water temperature KT by the water heater WH. At the end of the final rinse phase KP, the rinse liquid is pumped out of the wash cabinet SR as completely as possible by means of a drain pump. In the embodiment of Figure 4 The final rinse phase KP then ends at time tKE. This is followed at the start time tTS (= tKE) by the drying phase TP, which concludes the wash program and ends after a preferably predetermined period of time at time tTE.

The air conveying unit LF is switched on at least during a period of time, in particular at least during an initial period, preferably during the entire duration of the drying phase TP of the respective dishwashing program to be carried out, such as GP, EP. As a result, warm, humid washroom air PL is sucked from the washroom SR into the recirculation duct UK and blown through the fixed bed FS of the loose, granular, or granular, reversibly dehydratable sorption material SM to dehumidify it. The sorption material SM adsorbs water molecules from the warm, humid washroom air PL, so that the air that leaves the fixed bed FS on the outlet side and is blown into the washroom SR is drier than the warm, humid washroom air PL forcibly fed to the air inlet EI of the sorption container SOB. This dried air leaving the sorption container SB via its air outlet AU and returned to the washing chamber SR is in the Figure 1 denoted by TL. Due to the continued circulation of the warm, moist washroom air PL through the fixed bed FS of the sorption material SM, the washroom air in the washroom SR and the wash ware items accommodated therein become increasingly dry during the drying phase TP. The amount of sorption material SM is preferably such that at least the total amount of liquid adhering to the wash ware items can be largely or almost completely adsorbed by the sorption material SM during the drying phase TP. In particular, the sorption drying can partially avoid additional heating of the final rinse liquid during the final rinse phase KP. or be dispensed with entirely. Preferably, the final rinse temperature KT, to which the final rinse liquid has previously been heated up to the end of the final rinse phase KP in a household dishwasher without a sorption drying system, can be reduced in the household dishwasher according to the invention with a sorption drying system. This is because condensation drying or drying by means of its own heat, which is based on a sufficiently large temperature difference between the items to be washed and the boundary walls of the wash chamber SR, is now no longer necessary to such an extent or even not at all. The items to be washed in the wash chamber SR are now dried during the drying phase mainly by means of the sorption drying system in that the wash chamber air PL, which is present in the wash chamber SR after the last liquid-carrying wash phase, in particular the final rinse phase, is removed from the wash chamber air PL by the sorption material SM of the fixed bed FS during forced circulation through the recirculation air duct UK by means of the air conveying unit LF, i.e. water molecules are removed by adsorption. This saves thermal energy that would otherwise have to be generated by correspondingly converting electrical energy from the rinsing liquid heater or water heater WH in at least one of the preceding rinsing phases, in particular in the final rinse phase KP as the last liquid-carrying rinsing phase, to heat the rinsing liquid, in particular the final rinse liquid, to a sufficiently high temperature, in particular the required final rinse temperature or target final rinse temperature KT.

In order to regenerate the sorption material loaded with moisture after the drying phase of the respective dishwashing program, i.e. to make it sufficiently adsorbable, i.e. usable, for drying warm, humid dishwashing air PL during the drying phase TP of a subsequent, in particular next, dishwashing program, the water molecules adsorbed by it during the drying step of the preceding dishwashing program are actively expelled by heating the sorption material SM during the time period such as RD, KRD of a regeneration phase such as RG, KRG in a liquid-carrying rinsing step preceding the drying phase TP, in particular in a rinsing step with rinsing liquid that needs to be heated, preferably in the cleaning step RP, of this newly carried out dishwashing program such as GP, EP, by heating the sorption material SM during the time period such as RD, KRD of a regeneration phase such as RG, KRG. For heating, a desorption heating device HV is assigned to the fixed bed FS of the sorption material SM, which desorption heating device HV heats the sorption material SM during the duration such as RD, KRD of the regeneration phase such as RG, KRG at least temporarily. In particular, it may be expedient if the desorption heating device HV, in contrast to the air conveying unit LF, which preferably forcibly conveys air PL' from the wash cabinet through the sorption material SM for the entire duration of the regeneration phase, is switched on and operated in parallel with the air conveying unit, but is switched off a run-on period that is fixed for all dishwashing programs, i.e. always the same, before the end of the regeneration phase. During this run-on period, which is fixed for all dishwashing programs, it is therefore expedient for only the air conveying unit LF to continue running, while the desorption heating device HV is already out of operation. Due to the heat energy previously introduced into the sorption material by means of the desorption heating device HV, water molecules continue to be detached or desorbed from the sorption material, so that they are carried into the wash chamber SR by the air PL', which is still being forcibly conveyed by the air conveying unit LF. This mode of operation of the desorption heating device and air conveying unit saves electrical energy compared to an operating mode in which the desorption heating device and the air conveying unit are switched on simultaneously at the start of the regeneration phase and only switched off simultaneously at the end of the regeneration phase. During the regeneration phase, the air conveying unit LF is therefore preferably switched on continuously, so that air PL' is continuously forcibly conveyed from the wash chamber SR through the recirculation duct UK and thus through the sorption material of the fixed bed of the sorption container. The desorption heating device HV is designed here in the exemplary embodiment in particular as an electric air heater, which is provided in the first air duct section LK1 of the recirculating air duct UK in front of the inlet-side end face of the fixed bed FS, viewed in the forced air flow direction ZLS. The desorption heating device HV is located here in the exemplary embodiment of Figure 1 in particular in an anteroom of the sorption container SOB, which is arranged below the lower sieve grid US of the fixed bed FS. Due to the fact that the air PL', which flows through the fixed bed FS of the loose, granular or granular, reversibly dehydratable sorption material SM, is heated by the desorption heating device HV before entering the fixed bed FS, as viewed in the forced air flow direction ZLS of the air conveying unit LF, it is largely ensured that the air PL', which is supplied by the switched-on air conveying unit LF during Regeneration phase such as RG is promoted, flows into the fixed bed at a defined heating temperature and the heated air acts on the inlet side face, i.e. the inlet cross-sectional area, of the fixed bed FS, in a largely evenly distributed manner. In relation to the subsequent passage cross-sectional areas of the fixed bed at the various points of their vertical extension HS, the spaces between the loose grains or granulate particles of the sorption material SM are largely evenly flowed through by the air heated by the desorption heating device HV. This largely evenly transfers thermal energy or heat energy to the grains or granulate of the sorption material SM, which are arranged in the respective passage cross-sectional area of the fixed bed FS.

The regeneration phase such as RG, KRG is carried out during a liquid-carrying rinsing phase, preferably during a heating phase such as HP, HP' of a rinsing phase with rinsing liquid to be heated, preferably the cleaning phase such as RP, of the currently running dishwashing program such as GP, EP (see Figure 4 This means that when carrying out the respective dishwashing program in which the sorption drying system SY is used to dry the items to be washed during the program-final drying phase such as TP, the regeneration phase is carried out during at least one rinsing phase in which rinsing liquid is used before the final drying phase TP, so that the sorption material is sufficiently regenerated for this. The heating-up phase such as HP, HP' of the cleaning phase such as RP is preferably made up of at least two successive partial heating sections: The regeneration phase such as RG, KRG, in which the desorption heating device HV introduces thermal energy into the sorption material SM for its desorption, preferably takes place during a first partial section, in particular the initial section, of the heating-up phase such as HP, HP'. It is preferably immediately followed by a second time period such as PW, KPW, during which the washing liquid heater or water heater WZ ensures the further heating of the washing liquid up to a desired target temperature to be reached, such as the cleaning temperature RT or RT', as is the case for the dishwashing programs GP, EP in the Figure 4 During the regeneration phase such as RG, KRG, the air delivery unit LF is in operation to supply air PL' from the wash cabinet SR and blow it through the fixed bed FS made of loose sorption material SM via the recirculation duct UK and return it to the wash cabinet SR via the air inlet EL. During the period of time such as RD, KRD, during which the air conveying unit LF is activated, i.e. is in operation, the desorption heating device HV heats the wash cabinet air PL', which is forcibly fed to the sorption material SM by means of the air conveying unit LF, at least temporarily by introducing thermal energy in such a way that the sorption material SM water, which was stored in the sorption material SM during the drying phase TP of the previous dishwashing program, is sufficiently desorbed for the drying phase TP of the currently running dishwashing program. Part of the thermal energy provided by the desorption heating device HV is taken along by the air PL' flowing through the fixed bed FS and transported into the wash cabinet SR. This portion of the thermal energy generated by the desorption heating device HV can thus contribute to heating the washing liquid present in the wash cabinet SR, the wash cabinet air present there, and/or the washware. As a result, the washing liquid heater WH, which is preferably switched on and operated later than the desorption heating device HV intended for regenerating the sorption material, requires less electrical energy to heat the washing liquid to a required minimum temperature, such as RT during the cleaning step RP.

In order to further improve the energy efficiency of the domestic dishwasher GS during its operation, the invention provides that a control logic LO adjusts the conveying volume flow FV of the air conveying unit LF for the regeneration phase, such as RG, KRG, of the respective dishwashing program, such as GP, EP, in such a way that the regeneration temperature TR achieved in the sorption material SM varies in a specific dependence on the respectively specified regeneration time period or target regeneration time period, such as RD, KRD, of the regeneration phase, such as RG, KRG, of the respective dishwashing program, such as GP, EP. In this way, dishwashing programs with differently energy-intensive regeneration phases can be provided. The domestic dishwasher GS is therefore able to carry out its various dishwashing programs, such as the energy-saving dishwashing program, intensive cleaning program, hot cleaning program, Glass washing, short program, night rinse program, extra drying, etc. ... to switch to different operating modes or operating modes, which differ from one another in terms of the different lengths of their regeneration phases and the different target regeneration temperatures specifically assigned to them.

Figure 4 shows schematically that the regeneration phases RG, KRG of the two exemplary dishwashing programs GP, EP have different regeneration times RD, KRD. The regeneration phase RG, KRG of the respective dishwashing program GP, EP starts, for example, at the start time tRG = tRS of its cleaning phase RP. The regeneration time KRD of the dishwashing program EP is shorter than the regeneration time RD of the other dishwashing program GP, i.e. KRD < RD applies. The regeneration phase KRG of the energy-saving dishwashing program EP ends earlier at time tKRE, while the regeneration phase RG of the dishwashing program GP only ends later at time tRE (> tKRE).

The control logic LO is expediently a component of the control/monitoring unit CO, which is provided for executing the various dishwashing programs. The control/monitoring unit CO and/or the control logic LO are preferably implemented by one or more hardware components, which in particular comprise a microcomputer system with an electronic storage system, and/or software components which are stored in at least one electronic memory of a computer, in particular a microcomputer system, of the household dishwasher GS, and which contain and implement the sequence of operations, i.e., the sequence of one or more rinsing steps or rinsing phases and the final drying step of the respective dishwashing program. In particular, the control logic LO can be a program part or a subroutine of the sequence of operations of the respective dishwashing program to be executed, such as GP, EP.

When carrying out the regeneration phase such as RG, KRG of the various dishwashing programs such as GP, EP provided by the control unit CO, the control logic LO does not simply adjust the flow rate of the air conveying unit LF to the fact that for the regeneration of the loose Sorption material SM of the fixed bed FS always has the same target regeneration temperature RT equal to or above a limit temperature, which leads to the largely complete expulsion of the water adsorbed by the sorption material, but now makes a distinction according to the invention as to how high the regeneration temperature TR effected in the sorption material SM is in specific dependence on the respective specified regeneration time period such as RD, KRD of the regeneration phase such as RG, KRG of the respective dishwashing program such as GP, EP (see Figure 4 ). For the different lengths of time of the regeneration phases RG, KRG of the various dishwashing programs such as GP, EP, the control logic LO is therefore not based on always achieving the same target regeneration temperature TR equal to or above a limit temperature which leads to the almost complete expulsion of the water adsorbed by the sorption material by the end of the regeneration phase such as RG, KRG of the respective dishwashing program such as GP, EP, but the control logic LO changes the conveying volume flow of the air conveying unit LF and thus the regeneration temperature RT respectively achieved in the sorption material SM in a specific or individual manner depending on the length or duration such as RD, KRD of the regeneration phase such as RG, KRG of the respective dishwashing program such as GP, EP. In an advantageous manner, the thermal energy expenditure for the regeneration of the sorption material SM can thus be specifically or individually adapted to the respective regeneration time duration of the regeneration phase of the respective dishwashing program.

According to an advantageous development of the invention, the control logic LO can control the flow rate of the air conveying unit LF for the regeneration phase RG of at least one energy-saving dishwashing program to be carried out, such as EP (see Figure 4 ) in particular such that the regeneration temperature TR achieved in the sorption material SM is lower or less than the limit regeneration temperature above which the sorption material SM would almost completely desorb all of the water adsorbed by it during the sorption drying phase TP of a preceding dishwashing program. By deliberately lowering the regeneration temperature TR achieved below the limit regeneration temperature above which the sorption material would almost completely desorb all of the water adsorbed by it during the drying phase TP of a preceding Dishwashing program would desorb water almost completely, during the specified time period KRD of the regeneration phase KRG of the currently running energy-saving dishwashing program such as EP, the amount of water stored in the sorption material SM during the sorption drying phase TP of the preceding dishwashing program is deliberately not completely desorbed, but only partially until a deliberately increased minimum residual moisture amount or target residual moisture amount GW remains (see Figure 2 ) of water, which is more energy efficient, ie requires less thermal energy, than if the sorption material SM were heated at least to the limit regeneration temperature, above which the sorption material SM would almost completely desorb all of the water adsorbed by it.

Zeolite(s) of type A, and/or type Y, and/or type 13X are preferably provided as sorption material.

The control unit CO of the household dishwasher GS therefore preferably provides at least one energy-saving dishwashing program such as EP (see Figure 4 ), during which the household dishwasher GS is operated in a more energy-efficient regeneration operating mode than in other dishwashing programs provided by its control unit, such as GP. In this energy-saving dishwashing program, the control logic LO changes the conveying volume flow FV of the air conveying unit LF for the regeneration phase RG of this energy-saving dishwashing program, such as EP, in such a way that the regeneration temperature TR brought about in the sorption material is lower than the minimum limit regeneration temperature required for largely or almost complete desorption, so that a specifically increased minimum residual moisture or target residual moisture GW, in particular GW = 5% to GW = 15%, of water remains adsorbed by the sorption material SM of the fixed bed FS. The expulsion of this desired minimum residual moisture GW from the sorption material SM would require a disproportionately high expenditure of thermal energy RE, which would have to be provided by the desorption heating device HV by converting electrical energy into thermal energy. This is described in the Figure 2 schematically illustrated by a characteristic curve CK for zeolite, preferably of type 4ABf, as sorption material. The characteristic Curve CK indicates the regeneration energy RE in kilojoules per kilogram (abbreviated kJ/kg) that is required per adsorption volume W in cubic centimeters per gram (abbreviated cm ³ /g), i.e. volume of adsorbed water per dry mass of sorption material, to detach water molecules from the adsorption binding sites of the sorption material SM. The adsorption volume W is plotted along the abscissa, and the corresponding regeneration energy RE along the ordinate. In the diagram of Figure 2 The evaporation enthalpy, which must be generated during the regeneration phase by the desorption heating device when expelling the water adsorbed in and/or on the sorption material into the gas phase, has been omitted. This is because an amount of condensation energy corresponding to the evaporation enthalpy is recovered from the air that flows through the fixed bed during the regeneration phase, entraining the water vapor expelled by heating, after being returned to the purge chamber. The regeneration energy RE plotted along the ordinate thus essentially comprises the adsorption binding energy that must be generated to detach the water molecules from the sorption material, and additionally the sensible heat that is absorbed by the sorption material from the air forced through the fixed bed and heated by the desorption heating device and/or directly through its heating by the desorption heating device. The adsorption volume W corresponds to a percentage (abbreviated as %) of residual moisture that remains in the sorption material SM at the respective applied regeneration energy RE. For example, the value W = 0.05 cm ³ /g means that 0.05 l (liters) of water or 50 g of water per 1 kg of sorption material such as zeolite is adsorbed by it. In simple terms, a water volume per given sorption material dry mass of 5% corresponds to a residual moisture content of 5%. The total area below the characteristic curve CK represents the total amount of regeneration energy that is required to almost completely dry the total amount of sorption material, starting from its maximum saturation with water. For the example of Figure 2 For example, when using zeolite, preferably of type 4ABf, as sorption material, the saturation limit is around 25%, which corresponds to an adsorption volume value SW = 0.25 cm ³ /g. The characteristic curve CK can be viewed along the abscissa from right to left, starting from the adsorption volume value SW = 0.25 cm ³ /g, at which the sorption material SM is maximally saturated with water molecules, towards Adsorption volume value W = 0 cm ³ /g, which indicates the complete desorption of the sorption material, into a first curve section CK1 and a second curve section CK2. The first curve section CK1 is significantly flatter and lower than the second curve section CK2. The boundary between the two curve sections CK1, CK2 is marked by a dash-dotted vertical line and is labeled GW. It indicates the adsorption volume value - here in the embodiment of Figure 2 of W = 0.05 cm ³ /g - or, correspondingly, the minimum residual moisture value - here in the exemplary embodiment of approximately 5% - above which the requirement for regeneration energy RE to further reduce the amount of water remaining in the sorption material SM increases disproportionately or disproportionately. In the exemplary embodiment, this limit value GW = 0.05 cm ³ /g is assigned, for example, a regeneration energy value GRE = 1200 kJ/kg on the curve CK. While along the first, flatter and lower curve section CK1, from a higher residual moisture value, e.g. starting at the saturation residual moisture value SW of approximately 25%, by a predetermined differential step, e.g. from 5%, down to the lower minimum residual moisture value GW = 5%, the associated regeneration energy RE to be used increases approximately proportionally or disproportionately, the regeneration energy RE that must be used to expel the associated residual moisture in the sorption material increases disproportionately along the second curve section CK2. For example, in order to bring the water content or residual moisture in the sorption material SM from the minimum residual moisture value GW = 5% to 0%, more than a doubling of the regeneration energy RE to be used would be necessary. Thus, the residual moisture value GW = 5% is assigned a regeneration energy of GRE = 1200 kJ/kg, while the residual moisture value W = 0% is assigned a regeneration energy RE of more than 2400 kJ/kg. The area below the first curve section CK1 between the saturation value SW and the limit value GW corresponds to the total regeneration energy RE required to desorb the sorption material SM, starting from its saturation moisture value SW = 25% to the minimum residual moisture value GW = 5%. The working area below the first curve section CK1, which is flatter and lower than the second curve section CK2, is designated AB. The total area below the lower and flatter first curve section CK1 and the In contrast, the second, steeply rising and higher curve section CK2 corresponds to the total regeneration energy RE required to dry the sorption material SM from the saturation value SW of approximately 25% to a residual moisture content of 0%. This total area below the first curve section CK1 and the disproportionately rapidly rising second curve section CK2 is designated UB. In order to dry the sorption material SM from the minimum residual moisture value GW = 5% to a residual moisture content of almost 0%, i.e. to desorb it almost completely, a disproportionately high amount of regeneration energy RE is required. The first curve section CK1 is assigned an average regeneration energy mRE - here of approximately 750 kJ/kg - which is significantly lower than the average regeneration energy mRE' - here of approximately 1050 kJ/kg - assigned to the overall curve CK.

In general terms, the control logic LO preferably ensures that when carrying out at least one energy-saving dishwashing program such as EP, the regeneration temperature RT brought about in the sorption material SM during the respective predetermined duration such as KRD of the regeneration phase such as KRG causes water molecules to be detached only from those adsorption binding sites of the sorption material which require a lower average regeneration energy such as mRE compared to those adsorption binding sites of the sorption material for which a disproportionately higher regeneration energy per adsorption volume, i.e. volume of adsorbed water per dry mass of sorption material, is required. The regeneration is limited to the detachment of adsorbed water only from the adsorption binding sites of the sorption material with the weaker adsorption binding energy by deliberately lowering the regeneration temperature brought about compared to the limit regeneration temperature. The adsorption binding sites of the sorption material with a higher adsorption binding energy are, however, deliberately no longer used for the regeneration of the sorption material. This improves the energy efficiency during desorption or regeneration, i.e., a lower total amount of thermal energy is required to expel a desired volume of adsorbed water per dry mass of the sorption material. This is less, in particular between 20% and 60% less, than the total volume or the Total amount of water that can be adsorbed at most from the total amount of sorption material provided by the fixed bed during the drying phase of the preceding dishwashing program. However, in this way, less regeneration energy RE can be used to regenerate the sorption material SM, i.e. the electrical energy of the desorption heating device HV used for regeneration and the associated thermal energy generated by the desorption heating device can be used more efficiently for the desorption of the sorption material SM in order to expel a desired volume of adsorbed water per dry mass of sorption material. This is particularly advantageous for zeolite(s) of type A, type Y, and/or type 13X as sorption material.

In order to reduce the regeneration temperature achieved in the sorption material SM in a controlled manner during the regeneration phase to such an extent that a desired minimum residual moisture content or target residual moisture content, such as GW, remains in the sorption material SM, the control logic LO can increase the conveying volume flow or air throughput of the air conveying unit LF during the regeneration phase RG while the heating output HL of the desorption heating device HV is constant or fixed. To this end, the control logic LO, which is preferably a component of the control unit CO, sends at least one control signal SLD to the air conveying unit LF, preferably via a control line SL1. With a fixed heating output HL of the desorption heating device HV, the increase in the conveying volume flow caused by the air conveying unit LF leads to a reduction in the inlet or supply air temperature of the wash chamber air PL' entering the fixed bed FS according to the relationship ET = HL/(cp FV DI) + TPL', where ET is the supply air temperature of the wash chamber air PL' forced through the desorption heating device HV, HL is the fixed or constant heating output of the desorption heating device HV, cp is the specific heat capacity of the forced air PL', DI is the density of the forced air PL' in the wash chamber, FV is the conveying volume flow of the air PL' forced through the air conveying unit LF, and TPL' is the temperature of the air PL' conveyed out of the wash chamber into the recirculation duct UK upstream of the desorption heating device HV. For example, for a household dishwasher with a width of 60 cm and a sorption material mass, in particular zeolite mass, of approximately 1.3 kg and a fixed heating power HL of the desorption heating device HV of approximately 1450 It is advantageous to increase the volume flow for the air conveying unit (LF) so that it is approximately between 30 and 35 ^m³ /h during the regeneration phase. This allows for improved energy-efficient desorption of approximately 160 g of water.

If, in particular, a desorption heating device is assumed which preferably provides the same, fixed or constant electrical heating output for heating the air PL' forcibly conveyed by the air conveying unit LF for the regeneration phases of different dishwashing programs, it can be advantageous for the implementation of one or more more energy-efficient dishwashing programs, in particular energy-saving dishwashing programs (which are provided by the control/monitoring unit in particular alongside other, less energy-efficient dishwashing programs), to reduce the running time of the regeneration phase of the respective more energy-efficient dishwashing program compared to the regeneration phase of another, less energy-efficient dishwashing program and, accordingly, to additionally lower the respective regeneration temperature. This is because the electrical energy consumption of the desorption heating device is determined according to the relationship: the electrical energy consumption is directly proportional to the multiplication product of the regeneration time and the given electrical power HL of the desorption heating device HV.

The Figure 3 shows, by way of example, in relation to the zeolite types specified above and preferably provided, in a schematic representation the curves TRH, TRN of the resulting regeneration temperatures TR in degrees Celsius (abbreviated: °C), which are caused in relation to the total mass of the loose sorption material of the fixed bed at the various height positions HS (in meters (abbreviated: m)) of the height extension up to the specified bed height SH of the fixed bed FS of the sorption material SM with the same specified short regeneration time duration KRD, e.g. of about 10 minutes, for two different inlet temperatures ETH, ETN (with ETH > ETN) of the scavenging chamber air flow PL', which is forcibly conveyed through the fixed bed of the sorption material SM by means of the air conveying unit LF of the sorption drying system SY. The two different inlet temperatures ETH, ETN are each selected to be lower than the limit temperature of approximately 280°C for zeolite(s) of type A, type Y, and/or type 13X, which would lead to the almost complete expulsion of the water adsorbed by the sorption material. The temperature of the washroom air flow PL' at which it enters the fixed bed FS of the sorption material SM can be adjusted according to the inventive principle by changing the delivery volume flow of the air delivery unit LF. The higher the delivery volume flow FV of the air delivery unit LF, the more the inlet temperature of the forced air PL' can be reduced, which it has upon entering the inlet-side, in particular lower, end face of the fixed bed FS. If the air delivery unit LF is preferably designed as a fan, the delivery volume flow FV caused by it can be specifically adjusted by changing its speed. The speed of the fan is in the Figure 1 denoted by LD. An increase in the fan speed LD leads to an increase in the volumetric flow rate FV of air PL' produced by the fan, while a reduction in the speed results in a reduction in the volumetric flow rate FV of air PL' produced by the fan. For the desired speed change, the control unit LO sends at least one corresponding control signal SLD to the fan via the control line SL1. The total filling height SH of the fixed bed FS in this embodiment is Figure 3 approximately 0.06 m. In the first case, the purge chamber air flow PL', which is forced by the air conveying unit LF and enters the fixed bed FS, has an inlet temperature ETH = 250 °C. This lies above the range of reduced regeneration temperatures between 120 °C and 200 °C preferably provided for zeolite(s) of type A, Y, and/or 13X, which leads to an increased minimum residual moisture content or target residual moisture content between 5% and 15% based on the total mass of the sorption material in the fixed bed. The temperature profile designated TRH then occurs in the sorption material SM for the specified short regeneration period KRD - here approximately 10 minutes. Up to a height value HS of approximately 0.02 m of the fixed bed FS, an approximately constant regeneration temperature is achieved in the sorption material SM, which corresponds to the inlet temperature ETH of approximately 250 °C. This first section of the temperature curve TRH is in the Figure 3 denoted by TRH'. From this height value HS of 0.02 m up to the full filling height of SH = 0.06 m, the resulting regeneration temperature TR drops rapidly. This second section of the temperature curve TRH is shown in the Figure 3 with TRH". This means, however, that only in the front or flow inlet-side section, here in the exemplary embodiment in particular in the front third, of the fixed bed FS, an almost complete desorption of the sorption material occurs, while in Viewed from the direction of flow, the following section, here in the exemplary embodiment approximately the following two thirds of the height extension, of the loosely piled sorption material SM of the fixed bed FS is only partially desorbed. Preferably, the outlet-side, in particular upper, area of the fixed bed FS, ie the area of the sorption material SM in front of the downstream outlet of the fixed bed FS, is less or hardly regenerated, since there the temperature TR in the sorption material drops too far. This is the case here in the exemplary embodiment of Figure 3 This is the case from approximately the height position HS = 0.05 m, where the temperature TR induced in the sorption material drops to 100 °C and below. In order to desorb as much sorption material as possible over the entire height of the fixed bed FS as completely as possible, it would be logical to increase the inlet temperature of the air flow PL' at which it flows into the fixed bed FS via the inlet cross-sectional area, in the expectation that this will then also result in a higher temperature of the sorption material in the area of the outlet side of the fixed bed, viewed in the direction of flow, to better expel the adsorbed water molecules. Surprisingly, however, it has now been shown that this is counterproductive in order to be able to expel a desired, sufficiently large amount of water from the sorption material with the least possible regeneration energy. Rather, to desorb the water quantity stored in the sorption material during the sorption drying phase of the preceding dishwashing program, it is not necessary to increase the regeneration temperature, but rather, a reduced reduction regeneration temperature is sufficient to expel a sufficient portion of the water quantity adsorbed during the sorption drying process of the preceding dishwashing program to dry the items to be washed from the sorption material down to a minimum residual moisture quantity. Here in the embodiment of Figure 3 The inlet temperature of the air flow is reduced to the temperature value ETN = 200 °C by increasing the air flow rate of the air conveying unit LF. In the case of a fan, its speed is increased accordingly. The temperature value ETN = 200°C is the upper limit of the range of reduced regeneration temperatures between 120°C and 200°C preferably provided for zeolite(s) of type A, Y, and/or 13X, which leads to an increased minimum residual moisture or target residual moisture between 5% and 15% based on the total sorption material of the fixed bed. Surprisingly, this temperature level of ETN = 200 °C can be achieved further locally (in the direction of flow through the fixed bed) than in the case of the higher inlet temperature of ETH = 250 °C in the direction of flow along the longitudinal extent of the fixed bed. Here in the Figure 3 Up to a height position HS = 0.03 m of the fixed bed, an approximately constant temperature TR of 200 °C results in the sorption material SM. This first section of the temperature curve TRN, which is established for the lower inlet temperature of ETN = 200 °C, is designated TRN'. Only then, up to the maximum bed height value SH = 0.06 m, does the temperature curve TRN fall along its second section TRN". However, this happens later in relation to the height extension of the fixed bed, i.e. only from a greater height position HS, and also less steeply than in the case of the higher inlet temperature ETH = 250 °C of the temperature curve TRH. The temperature curve TRN intersects the temperature curve ETH shortly before the bed height value SH of about 0.03 m. From about half the height extension H of the fixed bed FS at HS = 0.03 m, the temperature curve section TRN" of the curve TRN lies above the temperature curve section TRH" of the curve TRH.

If the inlet temperature of the air flow is reduced - in particular by increasing the speed LD of the air conveying unit LF, which is preferably designed as a fan - a somewhat smaller amount of water is expelled from the sorption material SM along a first inlet-side section of the fixed bed FS, but the expulsion of water from the sorption material in the subsequent, outlet-side section of the fixed bed FS is now more successful than in the case of an air flow with a higher inlet temperature, such as ETH = 250 °C here. By lowering the inlet temperature of the air flow, the detachment of adsorbed water is specifically limited to those adsorption loading sites or binding sites of the sorption material with weaker adsorption binding energies. This prevents premature and excessive extraction and consumption of heat energy from the air stream by adsorption loading sites of the sorption material along the inlet side of the fixed bed, as these sites require overcoming higher adsorption binding energies to release the water molecules bound to them. In contrast, in the case of the air stream with the higher inlet temperature ETH = 250 °C, Along a partial section of the total height of the fixed bed FS, viewed in the direction of flow, water molecules are also detached from adsorption loading sites of the sorption material with stronger adsorption binding energies. This leads to an earlier and steeper drop in the regeneration temperature TR in the sorption material, here in the Figure 2 from a bed height HS of approximately 0.02 m, as shown by the temperature curve TRH in comparison to the temperature curve TRN. In the case of the temperature curve TRN with the lower inlet temperature ETN = 200 °C, however, the heat front of the air flow PL' flowing into the fixed bed FS penetrates further along the longitudinal extent of the fixed bed FS at the level of the inlet temperature of 200 °C, viewed in the direction of flow. In other words, this means that the particles or grains of the sorption material SM present further in the direction of flow towards the outlet AU of the fixed bed are heated up sufficiently so that more water molecules are detached from their adsorption loading sites than in the case of the temperature curve TRH. If the air inlet temperature is reduced to such an extent that, in the front or inlet-side zone of the fixed bed viewed in the direction of flow, the adsorption loading sites of the sorption material with higher adsorption binding energy are deliberately no longer used, the thermal energy introduced into the fixed bed FS by the air flow PL' can be transported further along the flow, in particular vertical extent, of the fixed bed, particularly advantageously to the outlet end of the fixed bed, with a sufficiently high thermal energy, which causes a sufficiently high regeneration temperature there to detach water molecules from adsorption loading sites of the sorption material with weaker adsorption binding energy. Overall, this results in a uniform heating and thus desorption of the sorption material across the entire bed height SH of the sorption material of the fixed bed FS, with an overall lower expenditure of thermal energy.

It can be particularly advantageous if the control unit CO of the household dishwasher GS has at least one energy-saving dishwashing program such as EP (see Figure 4 ), which, when carried out by the control/monitoring unit, the control logic LO determines the duration of the regeneration phase such as KRG compared to other implemented, less energy-efficient Dishwashing programs such as GP are shortened to a short regeneration period such as KRD and at the same time the regeneration temperature TR achieved in the sorption material SM is reduced to a reduced regeneration temperature, i.e. reduced regeneration temperature, such as ETN, compared to other selectable, less energy-efficient dishwashing programs such as GP. The reduced regeneration temperature refers to a regeneration temperature that is lower than the limit regeneration temperature above which the sorption material SM would almost completely desorb all of the water adsorbed by it during the drying phase of the preceding dishwashing program during the specified regeneration period. In particular, with regard to adsorption materials suitable for sorption drying, such as preferably zeolite(s) of type A, and/or type Y, and/or type 13X, it may be expedient if the control logic LO sets the short regeneration temperature, such as KRD for the regeneration phase of the energy-saving dishwashing program, such as EP, between 5 minutes and 15 minutes, and the conveying volume flow of the air conveying unit LF for the regeneration phase of the energy-saving dishwashing program in such a way that during the short regeneration period of the regeneration phase, a reduction regeneration temperature of at least 120 °C and at most 200 °C, in particular of at least 120 °C and at most 150 °C, is brought about in the sorption material SM, which is lower than the limit regeneration temperature, with regard to the amount of water expelled. This leads to an energetically optimized regeneration of the sorption material during the energy-saving dishwashing program. If a fan or blower is preferably provided as the air conveying unit LF, then with a fixed or constant heating output HL of the heating device HV, a reduction in the inlet temperature at which the forced air PL' enters the fixed bed FS can be ensured in a simple manner by increasing the speed of the fan or blower.

The reduction of the inlet temperature of the wash chamber air flow PL', which is conveyed into the fixed bed FS, below the limit regeneration temperature or limit temperature at which an almost complete desorption of the sorption material SM would be possible, is accompanied by an increased minimum residual moisture, in particular between at least 5% and at most 15%, preferably when using zeolite(s) of type X, type Y, and/or type 13X, in the sorption material SM remains. However, as the temperature curve TRN shows in a simplified and exemplary manner, the heat front advancing from the inlet of the fixed bed during the specified short regeneration period KRD in the sorption material SM, which is carried by the air flow PL' and has the level of its inlet temperature, can penetrate further or ideally all the way to the outlet end of the fixed bed FS and release water molecules from the adsorption bonds on the sorption material.

The Figure 4 illustrates the various liquid-carrying or water-carrying rinsing phases VP, RP, ZP, KP and the final drying phase TP of both the energy-saving dishwashing program EP and the less energy-efficient dishwashing program GP. In the energy-saving dishwashing program EP, the duration KRD of its regeneration phase KRG is shortened compared to the duration RD of the regeneration phase RG of the dishwashing program GP, i.e. KRD < RD applies. At the same time, in the energy-saving dishwashing program, the regeneration temperature TR produced in the sorption material during its shorter regeneration phase KRG is reduced compared to the regeneration temperature produced during the longer regeneration phase RG of the dishwashing program GP. For this purpose, the flow rate FV of the wash chamber air PL' forced through the fixed bed FS by means of the air conveying unit LF during the regeneration phase KRG of the energy-saving dishwashing program EP is increased compared to the flow rate of the wash chamber air PL' forced through the fixed bed FS by means of the air conveying unit LF during the regeneration phase RG of the dishwashing program GP. The desorption heating device HV operates with the same or approximately constant thermal output during the regeneration phases KRG and RG of these two programs EP and GP. Electronic power control is then not required for the desorption heating device HV. The heating phase HP, HP' of the cleaning phase RP of the respective program EP, GP preferably consists of a desorption heating phase KRG, RG, during which the air PL', which is forced into the fixed bed FS by the air conveying unit LF, is heated solely by means of the desorption heating device HV, and a subsequent rinsing liquid heating phase KPW, PW, during which only the water heating WH (with the desorption heating device HV switched off) The rinsing liquid - here in the cleaning step the cleaning liquid - is heated in the circulation circuit or rinsing liquid distribution circuit of the household dishwasher GS, which includes the circulation pump UP. Here in the embodiment of Figure 4 the shortened regeneration phase or desorption phase KRG of the energy saving program EP preferably takes place during an initial section of the heating phase HP of its cleaning phase RP from its start time tRS until the time tKRE. This regeneration phase KRG is followed from the time tWH = tKRE by the partial heating phase KPW of the cleaning liquid by means of the water heater WH until the wash cabinet SR, i.e. the wash liquid and/or wash cabinet air present there, is heated to the required cleaning temperature or target cleaning temperature RT, which is reached at the time tHE. The approximately straight-line temperature curve resulting in the wash cabinet SR during the short regeneration phase KRG is designated KTR, and the approximately straight-line temperature curve resulting in the wash cabinet SR during the heating phase of the liquid heater WH is designated KTW. The regeneration phase or desorption phase RG of the less energy-efficient dishwashing program GP preferably takes place during an initial subsection of the heating phase HP' of its cleaning phase RP, from its start time tRS until time tRE. This regeneration phase RG is followed by the partial heating phase PW of the cleaning liquid by means of the water heater WH, starting at time tWH' = tRE (> tKRE), until the wash cabinet SR or the wash liquid and/or wash cabinet air present there is heated to the required cleaning temperature or target cleaning temperature RT', which is reached at time tHE'(> tHE). The approximately straight-line temperature curve resulting in the wash cabinet SR during the regeneration phase RG of the less energy-efficient dishwashing program GP is denoted by VTR, and the approximately straight-line temperature curve resulting for the dishwashing program GP in the wash cabinet SR during the heating phase of the liquid heater WH is denoted by VTW. Both temperature curve sections VTR, VTW are shown in dash-dotted lines. The curve section VTR of the dishwashing program GP continues the curve section KTR of the energy-saving dishwashing program EP at approximately the same gradient, as the desorption heating device HV operates with the same constant heating output during the regeneration phases KRG, RG of both programs EP, GP. Here, in the exemplary embodiment of Figure 4 The cleaning temperature RT' of the energy-saving dishwashing program EP is exemplary selected to be equal to the cleaning temperature RT of the less energy-efficient dishwashing program GP, ie RT' = RT. In the dishwashing program GP, the dishwashing liquid heater WH is switched on later than in the energy-saving dishwashing program EP, at time tRE = tWH'> tWH, and is operated until the end time tHE' of the heating-up phase HP', at which time the required cleaning temperature RT' is reached. The temperature profile resulting in the dishwashing cabinet SR during the longer regeneration phase RG of the dishwashing program GP is designated VTR, and the temperature profile resulting in the dishwashing cabinet SR during the heating phase PW of the liquid heater WH is designated VTW. Since in the dishwashing program GP the dishwashing chamber temperature SRT that is set in the dishwashing chamber SR at the end tRE of its regeneration phase RG is lower than the dishwashing chamber temperature SRT that is set in the dishwashing chamber SR at the same time tRE in the energy-saving dishwashing program EP, the required target dishwashing chamber temperature RT' =RT is reached somewhat later in the dishwashing program GP by heating the dishwashing liquid using the water heater WH than in the energy-saving dishwashing program EP.

The regeneration phase RG of the dishwashing program GP includes a Figure 4 The approximately straight-line profile section VTR of the temperature SRT in the wash cabinet SR is shown in dash-dotted lines and extends the approximately straight-line profile section KTR of the wash cabinet temperature SRT, which results during the regeneration phase KRG of the energy-saving dishwashing program, at approximately the same gradient, since the desorption heating device HV operates with the same constant heating output HL during the regeneration phases KRG, RG of the two programs EP, GP. By shortening the time duration KRD of the regeneration phase KRG of the energy-saving program EP compared to the time duration RD of the regeneration phase RG of the dishwashing program GP, the heat input into the wash cabinet SR and the heat transfer to the dishwashing liquid present there is lower during the shorter regeneration phase KRG of the energy-saving dishwashing program EP compared to the heat input into the wash cabinet SR during the regeneration phase RG of the dishwashing program GP. For this purpose, the heating of the rinsing liquid and the washing chamber SR in the energy saving program EP takes place proportionally longer than in the heating phase HP' of the dishwashing program GP directly by the rinsing liquid heating WP in relation to the total time tHE - tRS of the heating phase HP during the time period tHE - tRE of the second section KPW of the heating phase HP of the cleaning phase RP. From an energetic point of view, this is more advantageous (than in the dishwashing program GP) because during the regeneration phase only a portion of the heat energy generated by the electrical desorption heating device HV is introduced into the wash cabinet SR by means of the forced air flow PL' during the cleaning phase RP and can contribute to heating the wash cabinet or the wash liquid introduced there. This is because the total heat energy generated to desorb the sorption material SM by means of the electrical desorption heating device HV is reduced by the thermal dissolution energy required to overcome the adsorption binding forces, by the sensible heat absorbed by the sorption material until the target regeneration temperature RT is reached, and by the waste heat losses of the heated sorption material to the environment of the sorption container. In other words, it is energetically more efficient to heat the rinsing liquid used for the cleaning cycle RP directly with the rinsing liquid heater WH than indirectly via the forced air flow generated for regeneration and heated by the desorption heating device HV. In addition to this shortening of the regeneration time, the regeneration temperature in the sorption material is also lowered or reduced in the energy-saving dishwashing program EP, as explained in detail above. This means that the fixed bed of sorption material is heated to a lesser extent and absorbs a lower amount of sensible heat and loses less waste heat to the environment. In addition, as viewed across the extension of the fixed bed in the flow direction, water molecules can be detached more frequently and more evenly from the adsorption binding sites of the sorption material with weaker binding energy, so that the total amount of sorption material can adsorb a specific, desired amount of water during the drying cycle. This preferably corresponds approximately to at least the total amount of water with which the items to be washed are wetted at the end of the last washing phase containing washing liquid, in particular the final rinse phase.

It may be useful if the air conveying unit LF has an additional air outlet to the environment. This is shown in the Figure 1 shown in dash-dotted lines and labelled AG. It can be opened and closed by means of the control unit CO via a control line SL3 using at least one control signal SLA. close. The additional air outlet AG is only opened during the drying phase of the respective dishwashing program. Through the additional outlet AG, an additional amount of exhaust air ALU can then be blown out of the wash cabinet SR into the environment, creating a negative pressure in the wash cabinet SR. As a result, ambient air UL is sucked into the wash cabinet SR through an inlet opening, such as an expansion opening in a wall of the wash tub. Figure 1 Such an inlet opening for ambient air is also shown in dash-dotted lines and labeled EO. This results in the wash cabinet air PL being mixed with the drier ambient air in the wash cabinet, which assists the drying of the items to be washed. It is advisable to only open the outlet AG to the environment during the drying phase, such as TP, of the respective dishwashing program, such as GP, EP, when at least some, or in particular a large part, of the moisture from the warm, humid wash cabinet air PL has been adsorbed by the sorption material SM. Since the sorption material SM is sufficiently desorbed, i.e. regenerated, at the start of the drying phase TP, it can adsorb water from the warm, humid wash cabinet air particularly efficiently during an initial period of the drying phase TP. Since the wash cabinet air is then already partially dehumidified, it is advantageous to only open the additional outlet AG to the environment then. This largely prevents any moisture damage to components of the household dishwasher or to neighboring kitchen furniture caused by the air escaping into the environment.

During the regeneration phase of the respective dishwashing program, however, the additional output AG remains closed to avoid unwanted thermal energy losses to the environment.

Claims (12)

1. Household dishwasher (GS)

   - having a dishwasher interior (SR) for receiving wash items to be cleaned,

   - having a control/monitoring unit (CO) for implementing a number of dishwasher cycles (GP, EP), wherein the respective dishwasher cycle (GP, EP) comprises one or more wash phases (VP, RP, ZP, KP), during which the wash items to be cleaned are applied with washing liquid, and a rinse cycle-concluding drying phase, and

   - having a sorption drying system (SY), which desorbs

   • a circulating air duct (UK) arranged outside of the dishwasher interior (SR) and fluidically connecting an air outlet (AL) of the dishwasher interior (SR) with an air inlet (EL) of the dishwasher interior (SR),

   • a sorption container (SOB) inserted fluidically into the circulating air duct (UK), in which sorption container (SOB) a fixed bed filling (FS) of a granular or granulate-type, reversibly dehydratable sorption material (SM) is accommodated,

   • an air conveyor unit (LF) inserted fluidically into the circulating air duct (UK), which, at least during a time segment, in particular initial time segment, of the drying phase of the respective dishwasher cycle to be carried out, forces warm and humid dishwasher interior air (PL) out of the dishwasher interior (SR) for dehumidification through the sorption container (SOB), and

   • a desorption heating apparatus (HV) with a fixedly predetermined heating power (HL), which takes place at least temporarily during a regeneration phase (RG, KRG), during which the air conveyor unit (LF) forces dishwasher interior air (PL') through the circulating air duct (UK), and in at least one washing phase, in particular the cleaning phase (RP), of the dishwasher cycle (GP, EP) to be carried out respectively, which heats the dishwasher interior air (PL') fed to the sorption material (SM) of the fixed bed filling (FS) by introducing thermal energy so that the sorption material (SM) desorbs water which has been stored in the sorption material (SM) during the drying phase (TP) of the temporally preceding dishwasher cycle,

   characterised in that
   the control/monitoring unit (CO) provides a number of dishwasher cycles (GP, EP), the regeneration phases (RG, KRG) of which have different regeneration durations (RD, KRD) and that a control logic (LO) for the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP) changes the delivery volume flow (FV) of the dishwasher interior air (PL') conveyed by the air conveyor unit (LF) as a specific function of the respectively predetermined regeneration duration (RD, KRD) of the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP) in such a way that the entry temperature (ET) of the dishwasher interior air (PL') conveyed into the fixed bed filling (FS) during the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP) and heated by means of the desorption heating apparatus (HV) and thus associated therewith the regeneration temperature (TR) effected in the sorption material (SM) by way of the throughflow extension (HS) of the fixed bed filling (FS) is adjusted as a specific function of the respectively predetermined regeneration duration (RD, KRD) of the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP).
2. Household dishwasher according to claim 1,
   characterised in that
   the desorption heating apparatus (HV) is an electrical air heater, which, viewed in the circulating air duct (UK) in the forced air flow direction (ZLS) of the air conveyor unit (LF), is provided upstream of the inlet cross-sectional surface of the fixed bed filling (FS) accommodated in the sorption container (SOB).
3. Household dishwasher according to at least one of the preceding claims,
   characterised in that
   the air conveyor unit (LF) is a fan, the rotational speed (LD) of which adjusts the control logic (LO) as a specific function of the respectively predetermined regeneration duration (RD, KRD) of the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP).
4. Household dishwasher according to at least one of the preceding claims,
   characterised in that
   the control logic (LO) is an integral part of the control/monitoring unit (CO).
5. Household dishwasher according to at least one of the preceding claims,
   characterised in that
   the control/monitoring unit (CO) provides at least one energy saving dishwasher cycle (EP), during the implementation of which the control logic (LO) shortens the regeneration duration of the regeneration phase (KRG) compared with the regeneration duration (RD) of the regeneration phase (RG) of at least one other selectable dishwasher cycle (GP) and at the same time increases the delivery volume flow (FV) of the air conveyor unit (LF) compared with the delivery volume flow of the air conveyor unit (LF) assigned specifically to the other dishwasher cycle (GP).
6. Household dishwasher according to claim 5,
   characterised in that
   during the implementation of the energy saving dishwasher cycle (EP), the control logic (LO) shortens the duration of the regeneration phase (KRG) compared with the regeneration duration (RD) of the regeneration phase (RG) of the other selectable dishwasher cycle (GP) to a short regeneration duration (KRD) and at the same time increases the delivery volume flow (FV) of the air conveyor unit (LF) compared to the delivery volume flow of the air conveyor unit (LF) assigned specifically to the other dishwasher cycle (GP) such that the regeneration temperature (TR) effected in the sorption material (SM) in the flow inlet side region of the fixed bed filling (FS) is reduced to a reduction regeneration temperature (TRN') which is lower than the regeneration temperature (TRH') effected in the sorption material (SM) during the other selectable dishwasher cycle (GP) in the flow inlet side region of the fixed bed filling (FS), and the regeneration temperature (TR) effected in the sorption material (SM) in a fluidically downstream region of the fixed bed filling, in particular the region assigned to the flow outlet of the fixed bed filling (FS), is reduced to an increase regeneration temperature (TRN") which is greater than the regeneration temperature (TRH") effected in the sorption material (SM) during the other selectable dishwasher cycle (GP) in the fluidically downstream region of the fixed bed filling, in particular the flow outlet of the fixed bed filling (FS).
7. Household dishwasher according to one of claims 5 or 6,
   characterised in that
   the control logic (LO) adjusts the short regeneration duration (KRD) for the regeneration phase (KRG) of the energy saving dishwasher cycle (EP), in particular when zeolite of type A, type Y and/or type 13X is used as sorption material, for less than or equal to 15 minutes, in particular between 5 minutes and 15 minutes, and at the same time increases the delivery volume flow (FV) of the air conveyor unit (LF) during the regeneration phase (KRG) of the energy saving dishwasher cycle (EP) so that during this short regeneration duration (KRD) of the regeneration phase (KRG) in the flow inlet side region of the fixed bed filling (FS), a reduction regeneration temperature (TRN') of at least 120° Celsius and at most 200° Celsius, in particular at least 120° Celsius and at most 150° Celsius is effected in the sorption material (SM).
8. Household dishwasher according to at least one of the preceding claims,
   characterised in that
   the control logic (LO) adjusts the entry temperature (ET) of the dishwasher interior air (PL') conveyed into the fixed bed filling (FS) to be lower, the shorter the duration (KRD) of the regeneration phase (KRG) of the respective dishwasher cycle, in particular energy saving dishwasher cycle (EO).
9. Household dishwasher according to at least one of the preceding claims,
   characterised in that
   the control/monitoring unit (CO) provides at least one energy saving dishwasher cycle (EP), in which, in order to reduce the entry temperature (ET) of the dishwasher interior air (PL') heated by means of the desorption heating apparatus (HV), said dishwasher interior air being conveyed into the fixed bed filling (FS) during the regeneration phase (KRG) of the energy saving dishwasher cycle (EP) by means of the air conveyor unit (LF), the control logic (LO) adjusts the delivery volume flow (FV) of the air conveyor unit (LF) compared with one or more less energy-efficient, other dishwasher cycles in such a way that the sorption material (SM) of the fixed bed filling (FS) is only brought to a regeneration temperature (TR) during the respectively predetermined regeneration duration (KRD) of the regeneration phase (KRG), at which regeneration temperature a minimum residual moisture (GW) of water of between 5% and 15%, in particular between approximately 10% and 15%, which is increased compared to the minimal residual quantity remaining adsorbed by the sorption material at the limit regeneration temperature, remains herein with respect to the overall dry mass of the sorption material (SM).
10. Household dishwasher (GS)

    according to at least one of the preceding claims,

    characterised in that

    for the predetermined duration (KRD) of the regeneration phase (KRG) of at least one energy saving dishwasher cycle (EP) a control logic (LO) adjusts the delivery volume flow (FV) of the dishwasher interior air (PL') conveyed by the air conveyor unit (LF) specifically so that during the duration (KRD) of the regeneration phase (KRG), water is only dissolved out from such adsorption binding sites of the sorption material (SM) by the regeneration temperature (TR) effected in the sorption material (SM) of the fixed bed filling (FS) during the respectively predetermined duration (KRD) of the regeneration phase (KGR), said adsorption binding sites requiring a lower average regeneration energy (mRE) compared with those adsorption binding sites of the sorption material (SM), for which a disproportionately higher regeneration energy (URE) is to be applied per adsorption volume (W), i.e. volume of adsorbed water per sorption material dry mass.
11. Household dishwasher according to claim 10,
    characterised in that
    during the implementation of the energy saving dishwasher cycle (EP) compared with one or more other dishwasher cycles (GP) provided by the control/monitoring unit (CO), the control logic (LO) increases the delivery volume flow (FV) of the air conveyor unit (LF) during the predetermined duration (KRD) of the regeneration phase (KGR) such that during the predetermined duration (KRD) of the regeneration phase (KRG) of the energy saving dishwasher cycle (EP), water is only dissolved off from the adsorption binding sites of the sorption material (SM), which require a lower average regeneration energy (mRE) compared with those adsorption binding sites of the sorption material (SM), for which a disproportionately higher regeneration energy (URE) per adsorption volume (W), i.e. volume of adsorbed water per sorption material drying mass, is to be applied, while the water at the adsorption binding sites of the sorption material (SM) remains with a disproportionately high binding energy (URE) per adsorption volume (W).
12. Method for operating a household dishwasher (GS) embodied in particular according to at least one of the preceding claims, which has:

    - a dishwasher interior (SR) for receiving wash items to be cleaned,

    - a control/monitoring unit (CO) for implementing one or more dishwasher cycles (GP, EP), wherein the respective dishwasher cycle (GP, EP) comprises one or more washing phases (VP, RP, ZP, KP), during which the wash items to be cleaned are applied with washing liquor, and a washing cycle-completing drying phase, and

    - a sorption drying system (SY), which desorbs

    • a circulating air duct (UK) arranged outside of the dishwasher interior (SR) and fluidically connecting an air outlet (AL) of the dishwasher interior (SR) with an air inlet (EL) of the dishwasher interior (SR),

    • a sorption container (SOB) introduced fluidically into the circulating air duct (UK), in which sorption container a fixed bed filling (FS) of a granular or granulate-type, reversibly dehydratable sorption material (SM) is accommodated,

    • an air conveyor unit (LF) inserted fluidically into the circulating air duct (UK), which forces the warm and humid dishwasher interior air (PL) out of the dishwasher interior (SR) for dehumidification through the sorption container (SOB) at least during a time segment, in particular initial time segment, of the drying phase (TP) of the respective dishwasher cycle (GP, EP) to be carried out, and

    • a desorption heating apparatus (HV) with fixedly predetermined heating power (HL), which takes place at least temporarily during a regeneration phase (RG, KRG), during which the air conveyor unit (LF) forces dishwasher interior air (PL') through the circulating air duct (UK) and which, in at least one dishwasher phase, in particular cleaning phase (RP), of the dishwasher cycle (GP, EP) to be carried out in each case, heats the dishwasher interior air (PL') supplied to the sorption material (SM) by introducing thermal energy in such a way that the sorption material (SM) desorbs water which has been stored in the sorption material (SM) during the drying phase (TP) of the temporally preceding dishwasher cycle,

    characterised in that
    a number of dishwasher cycles (GP, EP) are provided by the control/monitoring unit (CO), the regeneration phases (RG, KRG) of which have different regeneration durations (RD, KRD), and that by means of a control logic (LO) for the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP), the delivery volume flow (FV) of the dishwasher interior air (PL') conveyed by the air conveyor unit (LF) is changed as a specific function of the respectively predetermined regeneration duration (RD, KRD) of the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP) such that the entry temperature (ET) of the dishwasher interior air (PL') conveyed into the fixed bed filling (FS) during the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP) and heated by means of the desorption heating apparatus (HV) and thus also the regeneration temperature (TR) effected in the sorption material (SM) by way of the throughflow extension (HS) of the fixed bed filling (FS) is adjusted as a specific function of the respectively predetermined regeneration duration (RD, KRD) of the regeneration phase (RG, KRG) of the respective dishwasher cycle (GP, EP.

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