Household dishwasher with a sorption drying system and associated method for carrying out an energy-saving dishwashing program

Description

[0001] The invention relates to a household dishwasher with a washing chamber for receiving 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 washing phases, during which the items to be cleaned are exposed to washing liquid, and a drying phase concluding the washing program, and with a sorption drying system comprising a recirculating air duct arranged outside the washing chamber, which fluidically connects an air outlet of the washing chamber to 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 time period, in particular an initial time period,the drying phase of the respective dishwashing program to be carried out, warm, moist dishwashing air is forcibly conveyed from the dishwashing chamber through the sorption container for its dehumidification, and comprises a desorption heating device with a fixed predetermined heating output, 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, heats the dishwashing chamber air supplied to 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 temporally preceding dishwashing program.

[0002] 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.

[0003] 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" specified by the drying material manufacturer, in order to prevent it from overheating.

[0004] DE 10 2013 101 673 A1 discloses a method for operating a dishwasher having a sorption drying device, in which a desorption process suitable for releasing moisture is carried out by the sorption drying device 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.

[0005] In the sorption drying system of the dishwasher described in DE 10 2014 222 539 A1, air is drawn from the wash tub by a fan during recirculation mode 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.

[0006] 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 tub is blown through the sorption unit by the fan, thereby supplying thermal energy to the dry material via a heating device.

[0007] DE 10 2012 000 013 A1 describes a household dishwasher with a recirculation duct containing a sorber and a fan arranged upstream of it. The sorbent, partially loaded with water, is heated for desorption by direct, static heat application (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 in a manner not electrically insulated from the sorbent. After the static heat application has ended, a post-ventilation process follows, during which circulating air forced through the sorbent by the fan desorbs further water vapor from the sorbent.

[0008] 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.

[0009] 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 chamber air conveyed by the air conveying unit in a specific dependency on the respectively predetermined regeneration time duration of the regeneration phase of the respective dishwashing program in such a way that the inlet temperature of the wash chamber 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 predetermined regeneration time duration of the regeneration phase of the respective dishwashing program.

[0010] The control logic therefore individually or specifically adapts the flow rate of the wash cabinet air conveyed by the air conveying unit to the respective specified duration of the regeneration phase of the respective dishwashing program. If the control / monitoring unit has selected 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 the degree of soiling of the dishwashing liquid during the rinsing of the dishes to be cleaned is determined, preferably using at least one sensor such as a turbidity sensor, and used to automatically adjust at least one rinsing parameter and / or drying parameter, a quick program, an intensive cleaning program (in particular with an elevated temperature during its cleaning phase), a night-time cleaning program, a special program for glasswashing, etc., which differ from one another in the length of their regeneration phases, the control logic assigns different delivery volume flows or throughput rates, i.e., flow volume per unit of time, of the wash cabinet air conveyed by the air conveying unit during these regeneration phases to these different lengths of regeneration phases. Accordingly, the control logic adjusts the delivery volume flow of the wash cabinet air conveyed by the air conveying unit for the regeneration phase if the respectively selected dishwashing program changes the duration of its regeneration phase, i.e., extends or shortens it.For example, the current dishwashing program 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 with a full load of dishes. Through this individual or specific adjustment 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 used in a more energy-efficient orregenerate more energy-efficiently than if the air conveying unit were to convey the wash cabinet air with only one and the same, i.e. always the same, conveying volume flow value for the different lengths of regeneration phases of the various dishwashing programs.

[0011] When carrying out different dishwashing programs, the household dishwasher according to the invention preferably changes to different desorption operating modes or desorption operating modes for the respective regeneration of the sorption material of the fixed bed: The different dishwashing programs differ from one another in terms of the different lengths of regeneration time of their regeneration phases and the different inlet temperatures of the dishwashing chamber air heated by means of the desorption heating device, which are specifically assigned to these regeneration phases. During the different lengths of regeneration phases of the different 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 extension 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 durations 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 over its bed height extension in the flow direction, which are caused by different volume flow rates of the air conveying unit at a fixed or constant thermal (output) heating power of the heating device provided for desorption. The electrical energy consumption of a fixed, ieThe heating time of the desorption heating device providing constant heating power in relation to the respective dishwashing program to be carried out is determined primarily by the heating time during which it is in operation during the regeneration phase of the respective dishwashing program to be carried out. The shorter the regeneration phase of the respective dishwashing program is selected, 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 regeneration phase. It can even be selected to be shorter than this. For example, to save energy, the heating time can be reduced by a fixed amount for all dishwashing programs towards the end of the regeneration phase, ieThe remaining time 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 must always be shortened to the same extent. 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.

[0012] An electric heater, particularly an air heater, with a fixed or constant (output) heat 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 its thermal output is therefore not required for desorbing the sorption material.

[0013] By specifically adjusting the delivery volume flow of the air delivery unit by the control logic in relation to the respectively specified regeneration time duration of the regeneration phase of the respective dishwashing program, the regeneration temperature achieved in the sorption material can be varied in specific dependence on the respectively specified regeneration time duration or target regeneration time duration 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 means of the air delivery unit during the regeneration phase of the respective dishwashing program.The conveying volume flow indicates the volume of air that is moved, i.e. transported, by the air conveying unit per period of time through the recirculating air duct and thus through the fixed bed of loose, granular or granular, reversibly dehydratable sorption material.

[0014] According to an advantageous development of the invention, the air conveying unit is a fan or blower, the speed of which the control logic sets in a specific dependence on the respectively 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 respectively predetermined duration of the regeneration phase of the respective dishwashing program in such a way that the conveying volume flow of the forced-conveyed air generated by the fan during the respective regeneration phase of the respective dishwashing program, which flows at the fixed predetermined orThe constant heating power of the desorption heating device is applied at least temporarily during the respective regeneration period of the regeneration phase of the respective dishwashing program, resulting in a regeneration temperature in the fixed bed of 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 them, which are generated by different operating speeds of the fan.With regard to an individual dishwashing program in which the duration of its regeneration period is varied, a changed volume flow of the dishwashing chamber air is specifically assigned to this changed period in an analogous manner by the control logic due to a correspondingly changed speed of the fan.

[0015] 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 time 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 which leads to the water bound in the sorption material being largely or almost completely expelled by the end of the regeneration phase of the respective dishwashing program, but rather the control logic changes the conveying volume flow of the air conveying unit and thus, with a fixed or constant heating output of the desorption heating device provided for desorption, the regeneration temperature respectively 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.

[0016] In particular, the control logic can adjust the conveying volume flow 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 less than the limit regeneration temperature above which the sorption material would desorb largely or almost all of the water adsorbed by it during the sorption drying phase of a preceding dishwashing program. By deliberately lowering the achieved regeneration temperature below the limit regeneration temperature above which the sorption material would desorb almost entirely orwould 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 for the most part until a desired minimum amount of residual moisture or target amount of residual moisture remains (which is greater than the minimum remaining residual moisture in the sorption material during desorption 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, above which the sorption material would desorb almost all of the water adsorbed by it.

[0017] 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 in such a way that the regeneration temperature achieved in the sorption material is lower than the minimum limit regeneration temperature required for almost complete desorption, so that a desired minimum residual moisture orThe target residual moisture content of water remains adsorbed by the sorption material, which is now deliberately increased compared to the minimum residual moisture content adsorbed by the sorption material at the regeneration threshold temperature. Expelling this increased minimum residual moisture content from the sorption material would require a disproportionately high expenditure of thermal energy, which would have to be provided by the desorption heating device by converting a corresponding amount of electrical energy into thermal energy.

[0018] 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 run, where it can 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 base 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 base assembly and to neighboring components of the base 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.

[0019] According to an advantageous development of the invention, the control / monitoring unit of the household dishwasher according to the invention provides several dishwashing programs, each of which has a regeneration phase with different regeneration durations. For example, for an intensive cleaning program, a regeneration duration of 20–35 minutes can be selected for desorbing the sorption material, while for 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, a shorter regeneration duration of between 5–15 minutes can be set.

[0020] It can be particularly advantageous if the desorption heating device, which is provided 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 the sorption material accommodated 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 granular, reversibly dehydratable sorption material is heated upstream of the fixed bed by means of the electric air heater, 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 orHeat energy is supplied to the grains or granules of the sorption material in a largely uniform manner and is released to them in a largely uniform manner.

[0021] 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 carrying out 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 contain and implement the sequence procedure, 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 can be a program part orbe a subroutine of the sequence procedure of the respective dishwashing program to be carried out.

[0022] According to a further advantageous development of the invention, the control / monitoring unit provides at least one energy-saving dishwashing program. When executed 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, at the same time, during the regeneration phase of the energy-saving dishwashing program, increases the conveying volume flow of the air conveying unit 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 reduced 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 it adsorbed during the drying phase of the preceding dishwashing program during the specified regeneration period. The limit regeneration temperature for zeolite(s), in particular type A, type Y, and / or type 13X zeolite(s), as sorption material is approximately 280°C (Celsius).

[0023] 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 induced in the sorption material in the flow inlet-side region of the fixed bed during the other selectable dishwashing program, and the regeneration temperature induced 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 increased regeneration temperature that is greater than the regeneration temperature induced 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, during the other selectable dishwashing program. If the inlet temperature of the air flow conveyed into the fixed bed is reduced - in particular by increasing the speed of the air conveying unit, preferably designed as a fan -Although a slightly smaller amount of water is expelled from the sorption material SM along a first section of the fixed bed on the inlet side, the expulsion of water from the sorption material is now possible in the subsequent section, particularly on the outlet side, viewed in the direction of flow.The desorption of adsorbed water is better 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. This prevents premature and excessive extraction and consumption of heat energy from the air stream heated by the desorption heating device by adsorption loading sites of the sorption material along a section of the fixed bed in the inlet direction of flow during the specified regeneration period.which require overcoming higher adsorption binding energies to release the water molecules bound to them. In this way, viewed in the direction of flow, the heat front of the air flow flowing into the fixed bed advances further along the fixed bed at approximately the level of its inlet temperature and, compared to this level of the inlet temperature, decreases less or not at all along the further extension of the fixed bed 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 sorption material present further in the direction of flow towards the outlet or air outlet of the fixed bed are now also heated to a higher temperature.so that more water molecules are released from their 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 over 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.

[0024] 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 flow rate of the air conveying unit) to a lower value 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.

[0025] In particular, it may be expedient - preferably with regard to the sorption materials specified above - if the control logic sets the short regeneration time 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 time 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 in relation to the amount of water expelled during the energy-saving dishwashing program.

[0026] 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 carrying out 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 time as previously with longer regeneration times, but rather a reduced or even higher regeneration temperature compared to the regeneration temperatures of one or more other, less energy-efficient dishwashing programs.A reduced regeneration temperature, 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 carrying out the regeneration phase of the energy-saving dishwashing program in order to be able to expel a sufficient part of the amount of water adsorbed during the sorption drying cycle of the preceding dishwashing program for drying the items to be washed from the sorption material down to a minimum amount of residual moisture, which is now deliberately increased compared to the minimum amount of residual moisture remaining adsorbed by the sorption material at the limit regeneration temperature.This reduction in the regeneration temperature in the sorption material of the fixed bed, which is desired during the shortened regeneration phase of the energy-saving dishwashing program, is achieved by increasing the volume flow of the dishwashing chamber air through the fixed bed accordingly by means of the air conveying unit.

[0027] In summary, the control / monitoring unit advantageously provides 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 increased compared to the conveying volume flow of the air conveying unit during the regeneration phases of one or more other, less energy-efficient dishwashing programs.

[0028] 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 lowered. This temperature is caused by the forced-feed washroom air heated by the desorption heating device.

[0029] 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 and drying phases 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 across its height, has a cross-sectional area uniformly or homogeneously occupied by the sorption material at every point in the height and maintains this cross-sectional area permanently over the 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 granules of the sorption material are spherical.

[0030] 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 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, increases 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) that the sorption material of the fixed bed is brought to a regeneration temperature only overall during the respective predetermined regeneration period of the regeneration phase,in which a specifically increased minimum residual moisture content of between 5% and 15%, in particular between approximately 10% and 15%, based on the dry mass of the sorption material remains in the sorption material. (For example, with 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.) The control logic thus ensures that the regeneration temperature induced in the sorption material during the respective specified duration of the regeneration phase releases water only 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 that require a disproportionately higher regeneration energy per adsorption volume.That is, the volume of adsorbed water per dry mass of sorption material. Regeneration is limited by deliberately lowering the resulting regeneration temperature (compared to the limit regeneration temperature) to the removal of adsorbed water only from the adsorption loading sites of the sorption material with weaker adsorption binding energy. The adsorption loading sites of the sorption material with, in contrast, higher adsorption binding energy are deliberately no longer used. This improves the energy efficiency during desorption or regeneration.

[0031] 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 to be carried out compared to other dishwashing programs in which the sorption material is brought during the respective predetermined regeneration period of the regeneration phase at least to the limit regeneration temperature, from which the sorption material would almost or almost completely desorb all of the water adsorbed by it during the drying phase of a temporally preceding dishwashing program.Since those adsorption bonds that 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 the operation of 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 concluding 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.

[0032] Furthermore, the invention also relates to a method according to claim 12.

[0033] 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.

[0034] The invention and its advantageous embodiments and / or further developments as well as their advantages are explained in more detail below with reference to drawings.

[0035] They show, in a schematic principle sketch: Figure 1 is a schematic representation of 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 is a schematic representation of 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 available per adsorption volume, ieVolume of adsorbed water per dry mass of sorption material, to be used to release 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 can be used, Figure 3 is a schematic representation of the flow extension, in particular the 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 1is 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 the sorption drying system and is forced through the fixed bed of loose sorption material and is heated by a desorption heating device before it flows into the fixed bed, and Figure 4 shows a schematic representation of the various phases of an energy-saving dishwashing program according to the invention of the household dishwasher of Figure 1in 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.

[0036] Elements with the same function and mode of operation are provided with the same reference numerals in the figures.

[0037] 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 1Only 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.

[0038] The domestic dishwasher GS has a wash chamber SR for accommodating items to be cleaned. The wash chamber SR is defined by the walls of an approximately cuboid-shaped wash tub SB and a door, in particular a front door, closing its loading opening, in particular the front-side one. This is shown in the schematic front view of the Figure 1omitted 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 ceiling wall, a floor wall and a rear wall. In the washing chamber SR, one or more receiving units are provided for receiving 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 omitted for the sake of clarity of the drawing or for reasons of space in the Figure 1omitted. 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 crockery basket UB and an upper crockery 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 1For the sake of simplicity of the drawing, a water inlet system is let into the wash chamber SR. The wash liquid is pumped by means of a circulation 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. From the pump sump PS, the circulation pump UP sucks the wash liquid, 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 asa water diverter for selectively controlling the respective fluid line, which leads separately to the respective spray device or fluid distribution device. Furthermore, a fluid heater or water heater WH is provided in the fluid circulation circuit, in particular, in order to heat the rinsing fluid to a desired heating temperature or target heating temperature as needed. In this embodiment, . 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.

[0039] The sorption drying system SY has a recirculation duct UK located outside the wash cabinet SR. This recirculation 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 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 1in 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 every height point HS, and that this distribution of the loose sorption material SM is maintained permanently over the operating life of the household 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 first air duct section LK1. The air conveying unit LF is therefore preferably fluidically inserted into the recirculation duct ÙK between the air outlet AL of the wash cabinet SR and the air inlet EI of the sorption container SOB, upstream of the sorption container SOB, viewed in the flow direction of the wash cabinet air forcibly conveyed through it.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 in washroom air from the washroom SR 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 via the air inlet EI of the sorption container SB through the fixed bed of loose, granular or granular, reversibly dehydratable sorption material SM from bottom to top, in particular essentially in a vertical direction against the direction of gravity. The washroom air forcibly conveyed through the fixed bed FS leaves the sorption container SOB via an air outlet AU and is either directly or, as here in the embodiment from . 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 it 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 1indicated by directional arrows ZLS.

[0040] The household dishwasher GS comprises a control / monitoring unit CO for executing one or more dishwashing programs. Each dishwashing program comprises one or more rinsing phases, during which the items to be cleaned in the wash cabinet are sprayed with rinsing liquid by means of one or more spray devices or liquid distribution devices, and a drying phase concluding the wash program. It preferably comprises, in chronological succession, a pre-rinse phase, a cleaning phase, an intermediate rinse phase, and a final rinse phase as liquid-carrying rinsing phases or rinsing steps. Figure 4illustrates 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, as examples in detail. The time t in seconds (abbreviated as sec) is plotted along the abscissa, and the temperature SRT in degrees Celsius (abbreviated as °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 during the cleaning phase RP from the temperature curve TSR of the energy-saving dishwashing program EP.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 the exemplary embodiment for the sake of simplicity. Firstly, for the respective dishwashing program EP or GP, from the time tVS, fresh water at mains 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 dishwashing chamber SR for the pre-wash phase VP by means of the water inlet system (not shown) of the household dishwasher GS and during this pre-wash step is pumped to the spray devices or liquid distribution devices such asSV and sprayed or otherwise applied to the items to be cleaned. At the end of the pre-wash phase VP, the wash liquid is partially or completely 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 4at time tVE. Then, from the start time tRS (= tVE) of the subsequent cleaning phase RP, fresh water from the fresh water supply line and / or fresh water stored in a storage reservoir and / or process water is admitted into the wash chamber SR for the cleaning phase RP via the water inlet system (not shown) 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 time tHE or tHE'. Preferably already during the water inlet and heating up, the washing 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 rinsing liquid for the cleaning phase RP. After the required cleaning temperature RT or RT' has been reached at time tHE or tHE', the heating of the rinsing 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 the running circulation pump UP and applied to the items to be cleaned by 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 chamber SR by means of the drain pump (not shown).Then, at time tZS (= tRA), fresh water from the fresh water pipe and / or fresh water stored in the storage reservoir and / or service water is let into the wash chamber SR for a subsequent intermediate rinse step ZP via the water inlet system. This rinse liquid is then distributed in the wash chamber SR using the spray devices or liquid distribution devices such as SV. The water heater WH usually remains switched off for this intermediate rinse phase ZP. 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 using the drain pump. Then, for the final rinse phase KP following at time tKS (= tZE), fresh water from the fresh water pipe and / or fresh water and / or service water from the storage reservoir is again let into the wash chamber SR via the water inlet system.Rinse aid is preferably added to this fresh water and / or service water for 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 dishes to be cleaned in circulation mode. During the final rinse phase KP, the rinse liquid can, if necessary, be additionally heated to a required maximum rinse water temperature KT by means of the water heater WH. At the end of the final rinse phase KP, the rinse liquor liquid is pumped out of the wash cabinet SR as completely as possible by means of a drain pump. In the embodiment of . Figure 4The 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.

[0041] 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 leaving the fixed bed FS on the outlet side and being 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 1denoted by TL. Due to the continued circulation of the warm, moist washroom air PL through the fixed bed FS of 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 completely adsorbed by the sorption material SM during the drying phase TP. In particular, sorption drying makes it possible to partially or completely eliminate the need for additional heating of the final rinse liquid during the final rinse phase KP.Preferably, the final rinse temperature KT, to which the final rinse liquid is usually heated until the end of the final rinse phase KP in a household dishwasher without a sorption drying system, can be lowered in the household dishwasher according to the invention with a sorption drying system. Condensation drying or self-heat drying, which relies on a sufficiently large temperature difference between the items to be washed and the boundary walls of the wash chamber SR, is now less or even no longer necessary.During the drying phase, the items to be washed in the wash cabinet SR are now dried primarily by means of the sorption drying system. This is because moisture, i.e. water molecules, are removed by adsorption from the wash cabinet air PL, which is present in the wash cabinet SR after the last liquid-carrying wash phase, in particular the final rinse phase, by the sorption material SM of the fixed bed FS during forced circulation through the recirculation duct UK by means of the air conveying unit LF. This saves thermal energy that would otherwise have to be generated by correspondingly converting electrical energy from the wash liquid heater or water heater WH in at least one of the preceding wash phases, in particular in the final rinse phase KP as the last liquid-carrying wash phase, to heat the wash 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.

[0042] In order to regenerate the sorption material loaded with moisture after the drying phase of the respective dishwashing program carried out, i.e. to make it sufficiently adsorbable, i.e. usable, for drying warm, moist 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 to be heated, preferably in the cleaning step RP, of this newly carried out dishwashing program such as GP, EP.For heating purposes, a desorption heating device HV is assigned to the fixed bed FS of the sorption material SM, which heats the sorption material SM at least temporarily during the duration of the regeneration phase, such as RD, KRD, for example. 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 follow-up period that is fixed for all dishwashing programs, i.e. always the same, before the end of the regeneration phase. During this follow-up 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.In this exemplary embodiment, the desorption heating device HV is designed 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, as viewed in the forced air flow direction ZLS. The desorption heating device HV is located in this exemplary embodiment of . Figure 1in particular in an anteroom of the sorption container SOB, which is arranged below the lower sieve grid US of the fixed bed FS. Because the air PL', which flows through the fixed bed FS of the loose, granular or granular, reversibly dehydratable sorption material SM, viewed in the forced air flow direction ZLS of the air conveying unit LF, is heated by the desorption heating device HV before entering the fixed bed FS, it is largely ensured that the air PL', which is conveyed by the switched-on air conveying unit LF during the regeneration phase such as RG, flows into the fixed bed at a defined heating temperature and that the heated air acts on the inlet-side end face, i.e. the inlet cross-sectional area, of the fixed bed FS, in a largely evenly distributed manner.Relative to the subsequent passage cross-sectional areas of the fixed bed at the various points along its 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 air transfers thermal energy or heat energy largely evenly to the grains or granules of the sorption material SM arranged in the respective passage cross-sectional area of ​​the fixed bed FS.

[0043] 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 4This 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 carrying rinsing liquid 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 phases: 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 period, in particular the initial period, of the heating-up phase such as HP, HP'.It is preferably immediately followed by a second time section such as PW, KPW, during which the rinsing liquid heater or water heater WZ ensures that the rinsing liquid is further heated up to a desired target temperature to be achieved, such as the cleaning temperature RT or RT', as is the case for the dishwashing programs GP, EP in the . Figure 4is the case. During the regeneration phase such as RG, KRG the air conveying unit LF is in operation to suck in air PL' from the wash cabinet SR and blow it via the recirculation duct UK through the fixed bed FS made of loose sorption material SM and return it to the wash cabinet SR via the air inlet EL. During the period 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 later drying phase TP of the currently being carried out dishwashing program.A portion of the thermal energy provided by the desorption heating device HV is entrained by the air PL' flowing through the fixed bed FS and transported into the wash chamber SR. This portion of the thermal energy generated by the desorption heating device HV can thus contribute to heating the wash liquid present in the wash chamber SR, the wash chamber air present there, and / or the wash ware. As a result, the wash 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 wash liquid to a required minimum temperature, such as RT, during the cleaning step RP.

[0044] In order to further improve the energy efficiency of the household dishwasher GS during its operation, it is provided according to the invention that a control logic LO sets 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 brought about 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 household dishwasher GS is therefore able toEnergy-saving washing program, intensive cleaning program, hot cleaning program, glass washing, short program, night washing 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.

[0045] Figure 4shows 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).

[0046] The control logic LO is expediently a component of the control / monitoring unit CO, which is provided for carrying out 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 operations 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 carried out, such as GP, EP.

[0047] When carrying out the regeneration phase such as RG, KRG of the various dishwashing programs such as GP, EP provided by the control / monitoring unit CO, the control logic LO not only sets the conveying volume flow of the air conveying unit LF in each case so that for the regeneration of the loose sorption material SM of the fixed bed FS the same target regeneration temperature RT is always equal to or above a limit temperature, which leads to the almost 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 achieved in the sorption material SM is in specific dependence on the respectively 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 does not always ensure that the same target regeneration temperature TR is equal to or above a limit temperature which leads to the largely 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 dependence 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.

[0048] 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 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 sorption drying phase TP of a preceding dishwashing program. By deliberately lowering the achieved regeneration temperature TR 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, during the specified time period KRD of the regeneration phase KRG of the currently running energy-saving dishwashing program, such asEP, 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, 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.

[0049] Zeolite(s) of type A, and / or type Y, and / or type 13X are preferably provided as sorption material.

[0050] 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 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 necessary 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. Expelling this desired minimum residual moisture GW from the sorption material SM would in fact result in a disproportionate orrequire 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 explained in the . Figure 2 schematically illustrated using 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 is plotted along the ordinate. In the diagram of Figure 2The evaporation enthalpy, which must be generated by the desorption heating device during the regeneration phase when expelling the water adsorbed in and / or on the sorption material into the gas phase, is omitted. This is because an amount of condensation energy corresponding to the evaporation enthalpy is recovered from the air flowing through the fixed bed during the regeneration phase, entraining the water vapor expelled by heating, after its return to the purge chamber.The regeneration energy RE plotted along the ordinate thus essentially comprises the adsorption binding energy required to detach the water molecules from the sorption material, and additionally the sensible heat 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, this means that a water volume of 5% per given dry mass of the sorption material corresponds to a residual moisture content of 5%.The total area below the characteristic curve CK represents the total amount of regeneration energy required to almost completely dry the entire amount of sorption material, starting from its maximum water saturation. For the system used in the exemplary embodiment of . Figure 2For the zeolite used as an example, 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, in the direction of the adsorption volume value W = 0 cm 3 / g, which characterizes the complete desorption of the sorption material, divided 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 designated GW. It indicates the adsorption volume value - here in the embodiment of Figure 2of W = 0.05 cm 3 < / g - or correspondingly the minimum residual moisture value - here in the exemplary embodiment of about 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. 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 in the exemplary embodiment. While along the first, flatter and lower curve section CK1, a higher residual moisture value, for example starting at the saturation residual moisture value SW of about 25%, is assumed in each case by a predetermined difference step, such asfrom 5%, up to the lower minimum residual moisture value GW = 5%, the associated regeneration energy RE to be applied increases approximately proportionally or disproportionately, the regeneration energy RE to be applied 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 required regeneration energy RE would be necessary. For example, the residual moisture value GW = 5% is assigned a required regeneration energy of GRE = 1200 kJ / kg, while the residual moisture value W = 0% is assigned a required 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 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 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 value of 0%.This total area below the first curve section CK1 and the disproportionately rising second curve section CK2 is designated UB. To dry the sorption material SM from the minimum residual moisture content 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 approximately 750 kJ / kg – which is significantly lower than the average regeneration energy mRE' – here approximately 1050 kJ / kg – assigned to the entire curve CK.

[0051] In general terms, the control logic LO preferably ensures that when carrying out at least one energy-saving dishwashing program such as EP, water molecules are only released 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, ie volume of adsorbed water per dry mass of sorption material, is to be used by the regeneration temperature RT caused in the sorption material SM during the respective predetermined duration such as KRD of the regeneration phase such as KRG.By deliberately lowering the regeneration temperature compared to the limit regeneration temperature, regeneration is limited to the detachment of adsorbed water only from the adsorption binding sites of the sorption material with weaker adsorption binding energy. The adsorption binding sites of the sorption material with, in contrast, higher adsorption binding energy are 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 sorption material. This is less, in particular between 20% and 60% less, than the total volume orthe total amount of water that can be maximally adsorbed 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.

[0052] In order to reduce the regeneration temperature brought about 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 when the heating output HL of the desorption heating device HV is constant or fixed. To do this, the control logic LO, which is preferably a component of the control and monitoring unit CO, sends at least one control signal SLD to the air conveying unit LF, preferably via a control line SL1. When the heating output HL of the desorption heating device HV is fixed, the conveying volume flow brought about by the air conveying unit LF leads to a reduction in the inlet or outlet air flow.Supply air temperature of the washroom 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 washroom 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', FV is the flow rate of the air PL' forced through the air conveying unit LF, and TPL' is the temperature of the air PL' conveyed from the washroom into the recirculation duct UK upstream of the desorption heating device HV.For a household dishwasher with a width of 60 cm and a sorption material mass, particularly zeolite mass, of approximately 1.3 kg, and a fixed heating output HL of the desorption heating device HV of approximately 1450 W, 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 for the regeneration phase. This allows for improved energy-efficiency in the desorption of approximately 160 g of water.

[0053] 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 means of 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.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.

[0054] The Figure 3shows, by way of example, in relation to the above-mentioned, preferably provided zeolite types, in a schematic representation of the courses TRH, TRN of the resulting regeneration temperatures TR in degrees Celsius (abbreviated: °C), which are brought about 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 rinse 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 purge chamber 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 conveying volume flow of the air conveying unit LF. The higher the conveying volume flow FV of the air conveying 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 conveying unit (LF) is preferably designed as a fan, the volumetric flow rate (FV) it generates can be precisely adjusted by changing its speed. The fan speed is set 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 bed height SH of the fixed bed FS in this embodiment is Figure 3approximately 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. In the sorption material SM, the temperature profile designated TRH then occurs 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 3denoted 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 3with TRH". However, this means 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 approximately complete desorption of the sorption material occurs, while the following section viewed in the flow direction, 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 are only partially desorbed. Preferably, the outlet-side, in particular upper, area of ​​the fixed bed FS, i.e. 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 3This 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 stored in the sorption material during the sorption drying phase of the preceding dishwashing program, it is not necessary to increase the regeneration temperature. Instead, a reduced regeneration temperature is sufficient to expel a sufficient portion of the water adsorbed during the sorption drying process of the preceding dishwashing program to dry the washware from the sorption material, down to a minimum residual moisture content. Here, in the exemplary embodiment of . Figure 3The 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. Amazingly, this temperature level of ETN = 200 °C can then be achieved further locally (viewed in the flow direction of the fixed bed) than in the case of the higher inlet temperature of ETH = 250 °C viewed in the flow direction along the longitudinal extent of the fixed bed. Here in the Figure 3up to a height position HS = 0.03 m of the fixed bed, a more or less constant temperature TR of 200 °C results in the sorption material SM. This first section of the temperature curve TRN, which occurs 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, in relation to the height extension of the fixed bed, this happens later, 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 approximately 0.03 m.From about half of the height extension H of the fixed bed FS at HS = 0.03 m, the temperature profile section TRN" of the curve TRN lies above the temperature profile section TRH" of the curve TRH.

[0055] 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 removal and consumption of heat energy from the air stream by adsorption loading sites of the sorption material, which require overcoming higher adsorption binding energies to release the water molecules bound to them, already along a section of the fixed bed's inlet side, viewed in the direction of flow. In contrast, in the case of the air stream with the higher inlet temperature ETH = 250 °C, water molecules are also detached from adsorption loading sites of the sorption material with stronger adsorption binding energies along a partial section of the total height extension of the fixed bed FS, viewed in the direction of flow. This leads to an earlier and steeper drop in the regeneration temperature TR in the sorption material, here in the . Figure 2from 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 that are 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 temperature curve TRH. If the air inlet temperature is reduced in such a way that in the front or rear viewed in the direction of flowIf the adsorption loading sites of the sorption material with higher adsorption binding energy are deliberately no longer used in the inlet zone of the fixed bed, the heat 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 heat energy, which causes a sufficiently high regeneration temperature there to detach water molecules from the 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.

[0056] 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), when carried out by the control / monitoring unit, the control logic LO shortens the duration of the regeneration phase such as KRG in comparison to other implemented, less energy-efficient dishwashing programs such as GP to a short regeneration period such as KRD and at the same time reduces the regeneration temperature TR brought about in the sorption material SM in comparison to other selectable, less energy-efficient dishwashing programs such as GP to a reduced regeneration temperature, i.e. reduced regeneration temperature, such as ETN. The reduced regeneration temperature is understood to be a regeneration temperature which 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 in the sorption material SM a lower 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 effected compared to the limit regeneration temperature. This leads to an energetically optimized regeneration of the sorption material in the energy-saving dishwashing program with regard to the amount of water expelled.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.

[0057] Lowering the inlet temperature of the washroom air flow PL', which is conveyed into the fixed bed FS, below the limit regeneration temperature or limit temperature at which almost complete desorption of the sorption material SM would be possible is accompanied by an increased minimum residual moisture content, in particular between at least 5% and at most 15%, preferably when using zeolite(s) of type X, type Y, and / or type 13X, remaining in the sorption material SM. However, as the temperature curve TRN shows in a simplified and exemplary manner, the heat front advancing in the sorption material SM from the inlet of the fixed bed during the specified short regeneration period KRD, 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.

[0058] The Figure 4illustrates 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 achieved in the sorption material during its shorter regeneration phase KRG is reduced compared to the regeneration temperature generated 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 for the desorption heating device HV is then not required.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 forcibly conveyed into the fixed bed FS by means of 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 heater WH (with the desorption heating device HV switched off) heats the rinsing liquid - here the cleaning liquid in the cleaning step - in the circulation circuit or rinsing liquid distribution circuit of the household dishwasher GS comprising the circulation pump UP. Here in the embodiment of . Figure 4the shortened regeneration phase or desorption phase KRG of the energy saving program EP preferably takes place during an initial section of the heating-up phase HP of its cleaning phase RP from its start time tRS up to 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, 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 desorption phase RG of the less energy-efficient dishwashing program GP preferably takes place during an initial sub-section of the heating-up 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 segments VTR and VTW are shown in dash-dotted lines. The VTR curve segment of the GP dishwashing program continues the KTR curve segment of the energy-saving EP dishwashing program, approximately at the same gradient, but with a longer timescale, since the desorption heating device HV operates with the same constant heating output during the KRG and RG regeneration phases of both EP and GP programs. In this example, the KRG and RG regeneration phases are shown in . Figure 4For example, the cleaning temperature RT' of the energy-saving dishwashing program EP is selected to be the same as 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 cabinet SR at the end tRE of its regeneration phase RG is lower than the dishwashing chamber temperature SRT that is set in the dishwashing cabinet 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 by means of the water heater WH than in the energy-saving dishwashing program EP.

[0059] The regeneration phase RG of the dishwashing program GP includes a Figure 4The approximately straight-line curve section VTR of the temperature SRT in the wash cabinet SR is shown in dash-dotted lines and extends the approximately straight-line curve section KTR of the wash cabinet temperature SRT, which results when the regeneration phase KRG of the energy-saving dishwashing program is carried out, with approximately its gradient, since the desorption heating device HV operates with the same constant heating output HL in the regeneration phases KRG, RG of the two programs EP, GP.By shortening the duration KRD of the regeneration phase KRG of the energy-saving program EP compared to the 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 wash liquid present there is lower during the shorter regeneration phase KRG of the energy-saving dishwashing program EP than the heat input into the wash cabinet SR during the regeneration phase RG of the dishwashing program GP. In return, the wash liquid and the wash cabinet SR are heated proportionally longer in the energy-saving program EP, based on the total duration tHE - tRS of the heat-up phase HP, than in the heat-up phase HP' of the dishwashing program GP, directly by the wash liquid heater WP during the duration tHE - tRE of the second section KPW of the heat-up phase HP of the cleaning phase RP.This is more energy-efficient (than in the GP dishwashing program) 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, where it 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 more energy-efficient to heat the rinse liquid used for the cleaning cycle (RP) directly with the rinse 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 reduction in 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 results in the fixed bed of sorption material being heated to a lesser extent, absorbing a lower amount of sensible heat, and losing less waste heat to the environment.In addition, as the fixed bed extends 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 washware items are wetted at the end of the last wash phase containing wash liquid, especially the final rinse phase.

[0060] It may be useful if the air conveying unit LF has an additional air outlet to the environment. This is shown in the Figure 1shown in dash-dotted lines and labeled AG. It can be opened and closed by means of the control / monitoring unit CO via a control line SL3 using at least one control signal SLA. The additional air outlet AG is expediently 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 1such an inlet opening for ambient air is additionally shown in dash-dotted lines and labeled EO. In this way, the wash cabinet air PL is mixed with the drier ambient air in the wash cabinet, which assists the drying of the wash items. Advantageously, the outlet AG to the environment is only opened during the drying phase such as TP of the respective dishwashing program such as GP, EP when at least some, and in particular most, 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 air in the dishwasher is already partially dehumidified, it is advisable to open the additional outlet (AG) to the outside only then. This largely prevents any moisture damage to the components of the dishwasher or to neighboring kitchen units caused by the air escaping into the outside.

[0061] 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

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.