Patent Application
20240398205
The present invention relates to a dishwasher having at least one drying unit comprising a sorbent, through which in particular moist air from a dishwasher cavity, in which crockery, glasses, cutlery and the like can be processed, can be guided in a drying phase, wherein the dishwasher cavity is provided with a movable front door for loading or unloading, according to the preamble of claim 1.
With dishwashers of this type, it is desirable to be able to remove the items to be washed from the dishwasher cavity in as completely dry a state as possible and without water spots. However, at the same time, the energy input for the drying should be low; moreover a moistening of adjacent kitchen units or the countertop should be avoided.
It is advantageous to be able to remove moist air from the dishwasher cavity to ensure a good drying result of crockery, glasses, cutlery and the like, which can be processed in a dishwasher cavity. It is therefore known to connect the dishwasher cavity with an air outlet which transports moist air out from the dishwasher cavity into the external environment. An air outlet is thus frequently located in the upper region of a door on the front side or front door, which can be opened and closed in an automated manner. An air supply into this movable unit is therefore relatively complex and expensive, moreover, the high arrangement in the appliance poses the risk that cabinets or countertops located above the dishwasher or also parts of the dishwasher and its panels become damaged as a result of the extreme moisture or that the kitchen floor in the area in front of the dishwasher becomes wet and therefore slippery. Moreover, a significant draft is to be observed in the vicinity of such an air outlet, which is very uncomfortable particularly in small kitchens in which users are seated close to a dishwasher.
Alternatively to an air outlet in the front door, the front door of the respective household dishwasher is frequently also opened slightly during the drying phase of a dishwasher program to be performed in order to assist with the drying phase, so that moist dishwasher interior air escapes from the dishwasher interior of the dishwasher cavity into the environment at the installation site of the household dishwasher and can be replaced with comparably drier ambient air. A removal of thermal energy from the dishwasher interior, which is counterproductive in terms of energy since the heat is required for the drying process, is associated with such a door opening, particularly if it takes place in the initial phase of the drying phase. In particular, the problem associated with the door opening is therefore that in the process a significant amount of thermal energy is dissipated very quickly out of the dishwasher cavity into the environment, which conflicts with the desire for a good drying result.
It is further known to provide a sorbent, such as zeolite for instance, which, during the passage of air, can bind moisture herefrom and thus enables a recirculation of dried air into the dishwasher cavity in a recirculating air method. However, this sorbent must be regenerated with a high energy expenditure in order to be able to receive water again in the next wash cycle.
The problem underlying the invention is to achieve a high cost and energy efficiency while nevertheless drying the items to be washed very effectively by as much as possible largely avoiding applying steam to the surrounding furniture, the kitchen floor and parts to the front of the dishwasher.
The invention solves this problem with a dishwasher having the features of claim 1. For advantageous embodiments and developments of the invention, reference is made to claims 2 to 17.
The fact that, with the invention, during a drying phase a dishwasher guides a portion of the air out of the dishwasher cavity over a sorbent and back again dried and outwardly guides a portion by way of at least one air outlet, wherein the front door remains closed during the entire drying phase, means that a very effective drying is achieved in a combination of different drying principles. The partial blowing-out makes it possible for the sorbent not to become completely saturated with water and thus to be able to significantly lower the energy input for the regeneration of the sorbent by means of desorption. At the same time, the fact that the front door remains closed means that it is possible to dispense with a mechanism for automatic door opening, which simplifies construction and saves significant costs. By keeping the front door closed, a fast, high heat loss is further avoided so that in the further drying method sufficient thermal energy is still present in the dishwasher cavity for an optimized drying result,
When the air outlet for blowing out in particular moist air from a dishwasher cavity is arranged in the lower quarter of the appliance height and preferably extends as a slot outlet over at least two thirds of the width of the dishwasher, a draft can moreover largely be avoided. The wide extension enables a good distribution of the blown-out air without peaks.
Particularly favorably, the drying over the sorbent prevails in a first section of the drying phase and the drying by way of blowing out air prevails in a subsequent section. At the start of the drying process, when the moisture content is particularly high, the very effective adsorption drying, e.g. over zeolite, can thus provide for a quick reduction in the water content. At the same time, the recirculating air method is used in this phase so that barely any thermal energy is output into the environment.
In particular, the first section with the main adsorption drying can take up at least one third of the time of the drying phase, for instance approximately 60% of the time.
A very effective drying process in terms of energy can also be achieved if during the first section the air is guided completely over the sorbent and in a subsequent section the air is guided completely through the air outlet. The control effort is minimized and so too is the loss of thermal energy in the first section.
During a drying phase it is favorable for air to be guidable out of the dishwasher cavity optionally or together on the one hand to the air outlet and/or to the drying unit containing a sorbent. This permits maximum flexibility when selecting the respective drying principle.
Advantageously, for air guidance, a valve controller for further air guidance is arranged downstream of a conveyor organ (such as e.g. a fan), from which air is able to be drawn from the dishwasher cavity and forwarded. The conveyor organ can then continue to operate during suction operation, the hardware from a pure adsorption dryer can be maintained from the dishwasher cavity to the conveyor organ.
The air conveyor organ, in particular a fan, preferably runs continuously past the afore-mentioned two time segments of the drying phase. The drying phase is in particular the program-completing phase of a dishwasher program to be carried out after the end of its last washing liquid-conducting partial rinsing phase, in particular rinse-aid phase.
Provided the valve controller comprises a simple valve for opening or closing a blow-out line leading to the air outlet, this air outlet can be activated in addition to the zeolite drying.
If the valve controller comprises a three-way valve for setting different modes of operation, a pure recirculating air drying mode over the sorbent or a pure exhaust air drying mode through the air outlet or a combination of the two drying modes can optionally be set.
If the air outlet is arranged in the lower quarter of the appliance height, with a rise in the water vapor from the air outlet, the dishwasher is itself first impinged upon, so that a portion of the water can condense there and does not impact the furniture positioned thereabove. Moreover, as a result of the air outlet preferably extending as a slot outlet across at least two thirds of the width of the dishwasher, a wide distribution of the escaping moisture and mixing with the drier external air in the room is achieved. The escaping moist air is distributed in this way, a high input of moisture in the furniture is avoided. The draft is also significantly reduced by the good distribution width of the air.
Provided the air outlet has at least one air guiding element for the targeted discharge of air into the region in front of the front side of the dishwasher, which air guiding element pushes the outflowing air downward with a component, a rise in the warm air can be placed into a region far in front of the fronts of the kitchen units so that these remain protected from the impingement of moisture. On account of the blow-out component downward, the escaping air can firstly be guided away from the front of the kitchen unit in the region of the furniture panel, in particular also in the region of a front door of the dishwasher itself, and, as a result of its own heat, continue to rise just a few centimeters outside of the furniture.
An air guiding element is very favorably formed by an already existing wall which upwardly delimits the air outlet. Additional components are then avoided which simplifies construction and reduces material outlay.
If the air outlet is arranged on the front side of the dishwasher facing a user and the air is blown forward with a component, this ensures that the blown-out moist air cannot accumulate within a row of kitchen units, but can instead extend forward to the outside in order to permit a good distribution of the contained moisture.
If the air guiding element advantageously points downward to the front side by at least two degrees with respect to the horizontal, the blown-out moist air can be guided below a door leaf which projects with respect to the base, for instance, so that this remains free of moisture.
In particular, the air guiding element can point downward toward the front side by at least four degrees and thus firstly bring about a significant downward movement of the escaping airflow, before this rises on account of its heat far in front of the furniture units. At the same time, the downward movement then remains sufficiently small so that the escaping air does not leave behind a moist stain on the floor which may bring about a risk of slipping. In particular, the angular deviation against the horizontal therefore remains at less than ten degrees provided the air outlet is arranged in the upper region of a base of a dishwasher standing on the floor.
To externally delimit the airflow, a wall downwardly delimiting the air outlet can form a second air guiding element and with the first air guiding element form a blow-out channel of several centimeters in length which points in the direction of the front side. A defined, substantially laminar airflow is then enabled. The second air guiding element may be horizontal or rise slightly so as to achieve a nozzle effect by tapering the blow-out channel. The possible gradient of the second air guiding element is however smaller than the descending gradient of the upper air guiding element, in order in any case to maintain the downward component.
A channel which extends across its width and is upwardly open is very favorably located to the rear of the air outlet, in which channel partial flows of air which pass uniformly through the entire channel are guidable. Here a front edge of the channel can adjoin the essentially horizontally extended air outlet at an angle, which thus receives the widely distributed air from the channel and guides it out forward.
The partial flows in the cited channel are particularly favorably split from a shared airflow coming from the dishwasher cavity by way of an air distributor. Only one supply line is then required; the air is only divided upon entry into the channel.
If the air outlet is overall at least 40 centimeters wide in the case of a dishwasher with an appliance width of 60 cm, a very wide and uniform distribution of the moisture and the escaping air can be achieved. The width of the air outlet can particularly favorably approximately take over the entire appliance width.
In particular, the air outlet is embodied as a flat slot outlet with a height-to-width ratio of between 1:20 and 1:200, particularly favorably of approximately 1:100. Despite the structural and optically very minimal height, a high output surface can thus be achieved.
If the air outlet overlaps a base panel completing a base to the front and projects beyond this at least equidistantly from the front side, the moist air can escape sufficiently far forward so as not to impinge too heavily with moisture upon the kitchen floor nor the front side of the dishwasher, in particular a front door. The blown-out airflow can initially flow out in a slightly falling direction with an initial speed and on account of its high heat experience an upwardly rising component at a distance in front of the dishwasher.
Further advantages and features are disclosed in the exemplary embodiments of the subject matter of the invention shown in the drawing and described below.
In the drawings:
Here the household appliance shown schematically in
The household dishwasher 1 according to
The dishwasher cavity 2 is able to be closed off in particular on this front side V by means of a front-sided door or flap 3. This front door 3 is shown in
On the outer and front side V of the dishwasher 1 which is vertical in the closed position and faces toward the user, the door 3 can be provided with a décor panel 6 in order thus to experience a visual and/or haptic enhancement and/or an adaptation to surrounding kitchen units.
The dishwasher is embodied here as a free-standing or what is known as a partly integrated or fully integrated appliance. In the latter case, the appliance body G can also essentially be flush with the external walls of the dishwasher cavity 2. A housing surrounding the latter on the outside may then be unnecessary. A base 12 for receiving in particular functional elements, such as a pump for recirculating washing liquor, and also an air outlet 14 described further below, can be disposed in the lower region of the dishwasher.
In the exemplary embodiment according to the drawing, a control panel 8 extending in the transverse direction Q of the dishwasher in its upper region is assigned to the movable front door 3, it being possible for the latter to comprise an access opening 7 accessible from the front side V for manually opening and/or closing the front door 3. In the transverse direction Q, the dishwasher often has an extension of 45, 50 or 60 centimeters. In the depth direction T from the front side V rearward, the extension often also amounts to approximately 60 centimeters. The values are not mandatory. The dishwasher 1 also does not need to stand directly on a floor B, but may also be located approximately at eye height within a kitchen unit so that the draft problem through an air outlet 14 addressed in the introduction is to be considered in particular.
When the front door or flap 3 is closed, the dishwasher cavity 2 is delimited circumferentially by three solid vertical walls 13 and two horizontal walls 13 in total, of which one forms a ceiling (above) and a further one forms a base (below) of the dishwasher cavity 2. On the front side V facing the user, a left upright side wall 13 and a right upright side wall 13 adjoin to the left and to the right in the transverse direction Q in each instance.
The wall 13 which forms the base of the dishwasher cavity 2 and essentially downwardly delimits the same lies approximately horizontally above the base 12, i.e. in parallel with an external floor B on which the dishwasher 1 stands. A higher installation, for instance approximately at the height of a countertop, is possible, as stated, in particular within a furniture unit. The lower edge of the dishwasher 1 is then approximately 70 to 110 centimeters above the base in the installation position.
The dishwasher 1 is provided with at least one air outlet 14 for blowing out in particular moist air from the dishwasher cavity 2. This air outlet 14 can blow out air, in particular moist air, taken in from the dishwasher interior of the dishwasher cavity, into the free air space on the front side V of the dishwasher 1 facing a user so that the moist air is not input within a kitchen unit and may cause damage there as a result of moisture.
The air outlet 14 is an integral part of a blow-out assembly 15, which is shown overall approximately in
The blow-out assembly 15 can be formed from plastic overall. Furthermore, the air outlet 14 can be divided into a number of partial slots lying flush adjacent to one another. These also need not be the same length. It is important for overall a widely extended air outlet 14 to be created, which enables a high air throughput in order thus to achieve a wide distribution also of the moisture contained in the air.
The air outlet 14 is arranged here in the lower quarter of the appliance height and extends as a single or multipart slot outlet over at least two thirds of the width Q of the dishwasher 1. In particular, with a household dishwasher with an appliance width of 60 cm, the air outlet 14 is at least 40 centimeters wide. It can, as clearly apparent in
The dishwasher 1 is furthermore provided with at least one drying unit 16 comprising a sorbent, through which, in particular moist air from a dishwasher cavity 2, in which crockery, glasses, cutlery and the like can be processed, can be guided in a drying phase. The air thus guided and dried can then be guided back into the dishwasher cavity 2 by way of an outlet connecting piece 17 in the recirculating air mode.
The supply of air from the dishwasher cavity 2 is ensured here by way of an input nozzle 18 located in the upper region of the dishwasher cavity in an air supply 19, which embodies in particular a closed channel and leads to a conveyor organ 20, in particular a fan wheel, in order to take in and forward the air by way of the air supply 19.
Two possibilities are provided here for the forwarding: firstly by way of the first outlet 21 into the drying unit 16, secondly by way of the second outflow 22 to the widely extended air outlet 14.
This makes it possible for the dishwasher 1, during a drying phase, in particular a dishwasher program to be carried out, to guide a portion of the air out from the dishwasher cavity 2 by way of the drying unit 16 and the sorbent located therein and to guide a portion outward to at least an air outlet 14. In this way, the front door 3 remains closed during the entire drying phase, so that the heat loss out of the dishwasher cavity runs in a significantly slower and more controlled manner than in the case of a door opening.
In the cycle of the drying phase shown by way of example in
It is clear from
In particular, it may be that in the respective section the one or other drying mode not only prevails but during the first section 23, the air is guided completely over the sorbent and in a subsequent section 24 the air is guided completely through the air outlet 14. In particular, in the initial phase of the drying process, a complete recirculating air mode is then possible by way of the drying unit 16, so that practically no thermal energy required urgently for the drying process leaks out from the dishwasher cavity 2.
Nevertheless, it is possible during a drying phase for air to be guidable out from the dishwasher cavity optionally or together on the one hand to the air outlet 14 and/or to the drying unit 16 containing a sorbent.
To enable different modes of operation, for air guidance, a valve controller 25 for further air guidance is arranged downstream of the conveyor organ 20.
By way of example, a shared usage of the drying unit 16 and air outlet 14 is possible if the supply to the drying unit 16 is open and in the second outflow 22 to the air outlet 14 a simple open-closed valve is used as a valve controller 25, as shown in
As alternatively shown in
The air outlet 14 is arranged on the front side V of the dishwasher facing a user and for a low draft discharge of air, which avoids moisture damage in particular, into the region in front of the front side V of the dishwasher 1, comprises at least one air guiding element 26, here the top side of the actual diffusor 27, which pushes the outflowing air downward with a component. Therefore the exit of air to the front does not take place completely horizontally, but instead slightly downward.
Here the air guiding element 26 points downward to the front side V about at least two degrees. The descending gradient may also be larger and point downward about at least four degrees.
A downwardly delimiting wall is provided on the air outlet 14 with respect to the air guiding element 26, said wall forming a second air guiding element and in this way with the first air guiding element 26 forming a blow-out channel of several centimeters (typically approximately 5 to 8 centimeters) in length which points in the direction toward the front side V and tapers in the manner of a nozzle.
The air outlet with the blow-out channel which extends forward V can therefore also overlap a base panel 5 which clearly disengages with respect to a front door 3 and flush with a base 12 to the front and in this respect projects at least equidistantly from the front side V. As a result, the base panel 5 is itself not impinged upon with moisture. On account of the downward component, introduced by way of the air guiding element 26, in the blown-out airflow, this is however also run through below the front door 3 which projects further with respect to the front side V (e.g. 5 to 10 centimeters) without there moistening the decor element 6 to the front, for instance. Instead, the airflow is conveyed up to a few centimeters further forward V, before it can rise on account of the higher internal heat compared with the surrounding kitchen air. There, it is however sufficiently far from the front of the kitchen unit. At the same time, a moistening of the base B is likewise avoided by the only minimal descending gradient of the air guiding element 26. A bothersome draft is moreover prevented by the wide extension of the air outlet 14.
The conveyor organ 20 can also be controlled in a clocked manner, but also over a period of several days. Alternatively and particularly effectively, the conveyor organ is regulated by way of a moisture sensor system, which provides a measure of the current moisture of items to be washed located in the dishwasher cavity.
A dishwasher 1 of this type can also be effectively provided with what is known as a storage function, which makes it possible for the items to be washed to remain in the dishwasher cavity 2 after being processed without becoming moist again. This stay inside the dishwasher may last several days, without the dryness of the items to be washed deteriorating. The dishwasher 1 is then also used as a storage and drying cabinet, from which the items to be washed can be removed in a fresh and dry state.
In both cases, the conveyor organ is only switched on now and again, in order to consistently discharge moist air out of the dishwasher cavity 2 and thus to conserve the quality of the cleaning of the item to be washed also over a longer period of time. On account of the only minimally effective runtime, the energy requirement is low, so too is the sound level as a result of the at least one fan wheel or similar conveyor organ.
In order to feed moist air out from the dishwasher cavity 2 into the air outlet 14, at least one connection located on the rear of the air outlet 14 is provided. The air introduced through this connection can firstly be supplied to an air distributor, which projects into the cross-section of the tubular connection here and approximately centrally divides the airflow.
The air distributor passes into a curved air guiding element, which projects into a channel, which is arranged behind (therefore facing the front side V) the air outlet 14 in the transverse direction Q. The channel has a significantly larger height compared with the air outlet 14 and can have discharges for condensate water on its lower side.
The partial flows in the channel are therefore opposite to one another diametrically and run from the air distributor which is ideally central with respect to the transverse direction Q as far as approximately both external walls of the dishwasher 1. The partial flows have a sufficiently high speed, in order to obtain approximately a uniform density on their reciprocal paths through the channel, before the air can escape upward with a component and forward out of this into the actual diffusor 27.
The afore-cited channel ideally has a similarly sized extension to the diffusor 27 in the width direction Q, in particular at least 40 centimeters.
In particular, for this purpose the single or multipart air outlet 14 according to
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 211 144.0 | Oct 2021 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/076067 | 9/20/2022 | WO |
