EP3597096B1 - Method for carrying out a drying program section in a dishwasher and dishwashing machine for carrying out the method - Google Patents

Description

The invention relates to a method for carrying out a drying program section in a dishwasher, in particular a household dishwasher, with a washing container which has a loading opening on its front side for loading with items to be cleaned, which opening can be closed in a fluid-tight manner by means of a pivoted washing compartment door, and with a Condensation drying device comprising means for generating a flow of cooling air, part of the flow of cooling air being directed along a section of the underside of a worktop arranged above the washing container.

A generic method and a dishwasher for performing a generic method are from DE 10 2007 008 950 B4 known.

The ones from the DE 10 2007 008 950 B4 previously known dishwasher has a washing container, which in turn provides a washing chamber for accommodating items to be washed to be cleaned. For the purpose of loading the washing compartment with items to be cleaned, a loading opening on the washing container side is provided, which can be closed in a fluid-tight manner by means of a pivoting washing compartment door.

For the purpose of drying items to be washed which have been cleaned as intended, the dishwasher also has a condensation drying device which has means in the form of a blower for generating a flow of cooling air. According to this previously known construction, following a water-carrying program section for drying items to be washed, cooling air is sucked in by the fan and guided past the side surfaces of the washing compartment. As a result, the side walls of the rinsing compartment cool down, which in turn leads to the moisture condensing out of the process air located inside the rinsing compartment. The resulting condensate collects in the lower area of the rinsing tank, from where it can be pumped out.

In practice, it is not uncommon for the loading opening to leak through user-side pivoting of the washing compartment door or is automatically opened according to the program before the dishes are dried properly. The process air located in the rinsing container then escapes through the open loading opening, which can disadvantageously lead to the formation of condensate on the underside of a worktop arranged above the rinsing container.

To counter this disadvantage, it is from the DE 10 2007 008 940 B4 It is known to direct part of the flow of cooling air along a portion of the underside of a work surface located above the wash cabinet door. This measure advantageously leads to heating of the worktop, which minimizes the formation of condensate. The flow of cooling air that is guided past the washing container on the outside and is thereby heated can be guided at least partially past the underside of the worktop both before and after the washing compartment door is opened ajar.

The EP 1825800 A2 discloses a method for carrying out a drying program section in a dishwasher which has a fan for generating a cooling air flow which is guided past the washing compartment on the outside thereof. The cooling air flow is a mixture of ambient air and hot, humid steam drawn from the washing container and sucked in by the blower.

The EP 0536621 A1 discloses a dishwashing machine having a condensation chamber located above the wash tub. In the drying program section, warm, humid air, caused by thermal conditions, forces its way out of the wash cabinet through a ventilation opening into the condensation chamber. Colder, dry air from the engine compartment reaches the flushing compartment via another ventilation opening to equalize the air.

The EP 2371258 A2 discloses a drying process in which, in a first section, an air flow conveyed by a blower is guided past the washing compartment and below the worktop, and in a second section at least part of the air flow is guided into the washing compartment and out through the washing compartment door, which has meanwhile been opened a little escapes.

Although the from the DE 10 2007 008 950 B4 previously known implementation of the method has proven itself in everyday practical use, there is a need for improvement. It is In particular, the aim is to achieve an even more effective processing of the process, and this as far as possible independently of possible installation situations.

It is therefore the object of the invention to further develop a generic method such that an avoidance of undesired condensation on the kitchen furniture surrounding the dishwasher is ensured that is largely independent of the installation situation.

To solve this problem, a method with the features of claim 1 is proposed with the invention.

According to the invention, part of the cooling air flow generated is circulated in the bypass flow. Part of the process air that is routed past the rinsing tank on the outside is therefore in permanent air recirculation mode. This leads to the temperature level of the process air guided past the rinsing container on the outside increasing, specifically by 2 to 5 Kelvin, for example, depending on the application. In contrast to the prior art, this also increases the temperature of that part of the cooling air flow that is guided along a section of the underside of a worktop arranged above the washing compartment, with the result that the surface temperature of the underside of the worktop also increases accordingly. This leads to the positive effect of an even further reduction in the risk of condensation on the underside of the worktop.

Due to the increase in temperature, the relative humidity of the expelled air is also reduced, i.e. the part of the cooling air flow that is guided along the underside of the worktop. As a result, the expelled air can better absorb the vapors escaping after a door is opened, which also contributes to minimizing the formation of condensation on the underside of the worktop and on adjacent furniture fronts.

Due to the increased temperature of the cooling air flow emitted by the fan of the condensation drying device, the washing tank and its load cool down at a reduced rate, but this disadvantage is more than compensated for by the high volume flow, regardless of the installation situation, and the improved preheating and moisture absorption capacity. And so overall the positive effect outweighs it. Because the condensation can clearly be reduced, both on a worktop arranged above the washing compartment and on furniture adjacent to the dishwasher. According to tests by the applicant, an optimized result is achieved when the proportion of circulated process air is between 25% and 75% with a delivery volume between 25 m ³ /h and 65 m ³ /h.

The result of carrying out the method according to the invention is an increase in the temperature of the process air which is guided past the rinsing container on the outside due to a partial circulation operation. Compared to the prior art, this leads to an increase in the process air temperature, so that furniture adjacent to the dishwasher and/or a worktop arranged above the dishwasher can be heated to a higher level compared to the prior art, which then results in reduced condensation he brings.

According to a further feature of the invention, the cooling air flow results as a mixture of ambient air on the one hand and process air passed outside the rinsing container in the bypass flow on the other hand. The proportion of the circulated process air can be between 25% and 75%, for example. The higher the proportion of circulated process air in the cooling air flow, the higher the temperature level.

According to a further feature of the invention, the means for generating a flow of cooling air is a blower which sucks in a proportion of ambient air on the one hand and process air on the other. In a departure from the prior art, not only ambient air is sucked in by the blower, but also process air that is circulated, so that the result is a cooling air flow consisting of a mixture of sucked in ambient air and process air. The addition of circulated process air to the cooling air flow leads to the above-described increase in the temperature level of the cooling air flow.

In terms of device, the invention also proposes a dishwasher, in particular for carrying out the method described above, with a washing container which has a loading opening on its front side for loading with items to be cleaned, which can be closed in a fluid-tight manner by means of a pivoted washing compartment door, and with a condensation drying device , has the means for generating a flow of cooling air, wherein the means for generating the flow of cooling air is a fan which is arranged in a base below the washing compartment, the base having a recess formed in a front base panel for sucking in ambient air through the fan, to which the blower is fluidically connected by means of an intake manifold, the intake manifold being arranged with its end face facing the base panel and providing an intake opening at a distance from the base panel, leaving a gap space.

The dishwasher according to the invention has a fan, known per se from the prior art, for sucking in ambient air, which is guided over the outer walls of the washing compartment on the outlet side of the fan. The fan is arranged in a base of the dishwasher below the washing compartment. In a front plinth panel of the plinth, a cutout is formed, to which the blower is fluidically connected by means of an intake connector. In normal operation, this means that outside air can be sucked in by the blower via the cutout in the plinth panel and guided on the outside via the washing container.

According to the invention, it is now provided that the intake port of the blower is not connected airtightly to the recess formed in the base panel with its end face facing the base panel and providing an intake opening, but rather is arranged at a distance from the base panel, leaving a gap space. This results in a circumferential gap between the end face of the intake connection piece facing the base panel and the base panel, through which the process air flowing around the washing container can be sucked in and guided in circulation mode. The spaced-apart arrangement of the plinth panel and the intake port therefore ensures that not only ambient air is sucked in during normal operation, but also process air, with the result that ambient air is mixed with process air that has already been preheated. As a result of this constructive design, a flow of cooling air is released from the fan, which is at a higher temperature level than in the prior art, so that only ambient air is sucked in. This refinement provides the advantages already explained above.

It is provided according to a further feature of the invention that the cross-sectional area of the intake opening of the intake manifold and the cross-sectional area of the

Recess in the base panel are aligned parallel to each other. This achieves a uniform suction of process air that is distributed homogeneously over the surrounding gap space, so that an optimized mixing of newly sucked-in ambient air and process air guided in circulation mode is achieved.

wobei α zwischen 5 mm und 25 mm, vorzugsweise zwischen 12 mm und 18 mm beträgt.The cross-sectional areas of the intake opening and recess are to be designed depending on the gap dimensions between the front side of the connection piece and the base panel. Alternatively, the gap dimension depends on the given cross-sectional area. It is preferred that the gap size is a function of the ratio of the cross-sectional area of the recess in the base panel to the cross-sectional area of the intake opening of the intake manifold, specifically as $$\mathrm{gap\; dimension}\mathrm{\beta }\left(\mathrm{X}\right)=\frac{\mathrm{Cross\; sectional\; area}\mathrm{the}\mathrm{recess}}{\mathrm{Cross\; sectional\; area}\mathrm{the}\mathrm{intake\; port}}\cdot \mathrm{a},$$

where α is between 5 mm and 25 mm, preferably between 12 mm and 18 mm.

A possible gap size between the base panel and the end face of the intake manifold is, for example, between 4 mm and 12 mm, preferably between 6 mm and 10 mm, even more preferably between 7 mm and 9 mm. The cross-sectional areas of the intake port and recess can each be between 20 cm ² and 70 cm ² , preferably between 30 cm ² and 60 cm ² , even more preferably between 40 cm ² and 50 cm ² .

According to a further feature of the invention, it is provided that the cross-sectional area of the recess in the base panel is blocked. Such an interlocking achieves a reduction in the cross-sectional area, which means that the gap size between the end face of the connecting piece and the base panel can be influenced constructively. The blocking, ie the reduction of the cross-sectional area of the cutout in the base panel, can be implemented by different structural implementations. In the simplest configuration, the diameter of the recess is reduced. Alternatively, ribbing can be provided, according to which a recess with a plurality of passage openings is formed, which are each separated from one another by a rib. The advantage of such a ribbing is that a support device for a protective device for the fan is provided, for example for receiving and support of a sieve.

According to a further feature of the invention, it is provided that the cutout provided by the base panel is equipped with an air guiding element on the intake port side. Such an air guiding element can be, for example, a ring surrounding the recess on the intake port side. Such an air guide element promotes the inflow of the bypass flow.

As a result, the design according to the invention provides a number of advantages. On the one hand, the configuration according to the invention is significantly more robust with regard to installation situations, i.e. the respective installation situation has at most a marginal influence on the function of the vapor protection. Because the recirculation of already preheated process air ensures that the volume converted by the blower cannot collapse too much and, regardless of the installation situation on site, leads to an increase in temperature in the process air flow, with the result that that improved heating of a worktop arranged above the dishwasher and/or furniture adjacent to the dishwasher is achieved, with the result that the risk of condensation is minimized. A possibly lower proportion of fresh air is thus compensated for by increasing the temperature of the outlet air. Adequate vapor protection is thus ensured even in an installation situation with a high degree of blocking, for example in the case of a tall cupboard installation.

The design, which is deliberately designed to keep the base panel and the intake manifold apart, makes the sealing, which was still required according to the prior art, for example using a bellows between the recess in the base panel and the intake manifold, superfluous. This reduces the material and assembly costs.

In addition, it is possible to be able to use a blower with reduced motor power due to the at least partial recirculation of process air in the circulation mode. This also contributes to cost reduction.

Finally, in contrast to the prior art, a fan that is not as large in volume is required, which makes it possible to reduce the size of the fan, which leads to a reduced installation space.

Last but not least, the process air discharged to the outside is maximized in terms of its ability to absorb moisture, so that vapors escaping from an open loading opening can be better absorbed, ie can be diluted by the process air.

Fig. 1

Darstellung einer erfindungsgemäßen Geschirrspülmaschine,

Fig. 2

in schematischer Perspektivdarstellung ausschnittsweise eine Sockelblende;

Fig. 3

in schematischer Perspektivdarstellung eine in einer Sockelblende ausgebildete Aussparung gemäß einer ersten Ausführungsform;

Fig. 4

die Darstellung nach Figur 3 mit eingezeichneter Querschnittsfläche;

Fig. 5

in schematischer Perspektivdarstellung die sockelblendenseitige Stirnseite eines Ansaugstutzens;

Fig. 6

in schematischer Darstellung in Seitenansicht die beabstandete Anordnung von Ansaugstutzen und Sockelblende

Fig. 7

in schematisch perspektivischer Darstellung die in einer Sockelblende ausgebildete Aussparung gemäß einer zweiten Ausführungsform;

Fig. 8

schematisch perspektivischer Darstellung die in einer Sockelblende ausgebildete Aussparung gemäß einer dritten Ausführungsform;

Fig. 9

in schematischer Seitenansicht eine Sockelblende gemäß einer ersten Ausführungsform

Fig. 10

in schematischer Seitenansicht eine Sockelblende gemäß einer zweiten Ausführungsform;

Fig. 11

in schematischer Seitenansicht eine Sockelblende gemäß einer dritten Ausführungsform;

Fig. 12

in schematischer Seitenansicht eine Geschirrspülmaschine nach dem Stand der Technik;

Fig. 13

in einer Schemadarstellung die Geschirrspülmaschine nach Figur 12.

Further features and advantages of the invention result from the following description based on the figures. show:

1

Representation of a dishwasher according to the invention,

2

in a schematic perspective view of a section of a base panel;

3

a schematic perspective view of a recess formed in a base panel according to a first embodiment;

4

the representation figure 3 with marked cross-sectional area;

figure 5

in a schematic perspective view, the base panel-side face of an intake manifold;

6

in a schematic side view of the spaced arrangement of intake manifold and base panel

7

in a schematic perspective view, the recess formed in a base panel according to a second embodiment;

8

schematic perspective view of the recess formed in a base panel according to a third embodiment;

9

in a schematic side view a base panel according to a first embodiment

10

a schematic side view of a base panel according to a second embodiment;

11

a schematic side view of a base panel according to a third embodiment;

12

a schematic side view of a dishwasher according to the prior art;

13

the dishwasher in a schematic representation figure 12 .

figure 12 shows a dishwasher 1 according to the prior art in a purely schematic side view.

The dishwasher 1 has a housing 2 that accommodates a washing container 3 . The washing compartment 3 in turn provides a washing chamber 4 for receiving items to be washed to be cleaned. A loading opening 5 , which can be closed in a fluid-tight manner by means of a washing compartment door 6 , is used for the user to load the washing compartment 3 with items to be cleaned. In this case, the washing compartment door 6 is mounted such that it can pivot about a horizontal axis of rotation 29 .

The dishwasher 1 also has a base 9 arranged vertically below the washing compartment 3 . The base 9 ends at the front with a base panel 15 . The base 9 houses a condensation drying device 14. In the form of a fan 10, this has means for generating a cooling air flow 8. The fan 10 has a fan wheel 12 arranged in a housing 11, which is driven by a motor 13 in the intended operating case .

The blower 10 is fluidically connected to a recess 16 formed in the base cover 15 by means of an intake connection 17 . In normal operation, ambient air is sucked in by the blower 10 through the recess 16 in the base panel 15 and is then conveyed through the intake port 17 to the outlet side of the housing 10 to form the cooling air flow 8 .

figure 13 shows the design according to the prior art in a further schematic representation. As can be seen from this representation, the ambient air is 19 sucked in by the blower 10 with the interposition of the intake connection 17, the blower 10 emitting a flow of cooling air 8 applied to the outside of the washing compartment 3. A part 18 of the cooling air flow 8 is guided along a section of the underside of a worktop 7 arranged above the washing compartment 3 . As a result, the worktop heats up on the underside, which leads to a reduced formation of condensate on the worktop when vapors escape from the washing compartment 4 as a result of a washing compartment door being opened.

The configuration according to the invention is shown in a schematic representation in figure 1 shown. How to compare the figures 1 and 13 results, it is provided according to the invention that part of the cooling air flow 18 is circulated in a bypass flow 20 and is guided past the washing compartment 3 on the outside thereof. Structurally, this implementation of the method is achieved in that the intake connector 17 does not lie tightly against the recess 16 provided by the base cover 15, but rather that the intake connector 17 is provided with its end face 23 facing the base cover 15 and providing a suction opening 27, leaving a gap 28 is arranged at a distance from the base panel 15, as is also the case in particular according to the illustration figure 6 reveals.

The inventive spaced arrangement of base cover 15 and intake port 17 contributes to the fact that air previously sucked in as ambient air 19 by fan 10 can be guided past the washing compartment 3 in circulation mode by the process air surrounding washing compartment 3 being sucked in again and via the gap between the base cover and intake port the flushing tank can be pressurized with air again. In this respect, according to the configuration according to the invention, a mixing of newly sucked-in ambient air 19 and process air 26 conducted in the circulation mode takes place.

The result of this implementation of the method is that the part 18 of the cooling air flow 8, which is guided along a section of the underside of a worktop arranged above the washing compartment 3, has a higher temperature than the cooling air flow 8 according to the configuration according to the prior art case is. The bypass routing according to the invention therefore leads to an increase in the temperature level in the cooling air flow 8.

The result of carrying out the method according to the invention is that the worktop is also heated more than in the prior art, which results in a significant reduction in the formation of condensate on the underside of the worktop.

Another advantage of the temperature increase is that the relative humidity within the flow of cooling air emitted to the outside is reduced in contrast to the prior art, so that if the door is opened from the washing compartment 4, moist air, i.e. vapors, can be better absorbed. This also contributes to minimizing the formation of condensation on the underside of the worktop 7.

The others Figures 2 to 11 show constructive versions of the embodiment according to the invention in detail.

figure 2 shows a schematic perspective view of the base panel 15 that covers the base 9 at the front. In this case, a through-opening is provided between two adjacent ribs, the through-openings together defining the recess 16 . The blower 10 is arranged behind the base panel 15 in the direction of flow and is fluidically connected to the recess 16 with the interposition of a connecting piece 17 . This factual connection can be seen from the schematic representation figure 3 also recognize.

figure 4 shows the recess 16 in the base panel 15 in detail in a schematic representation. The total cross-sectional area 22 provided by the recess 16 is shown hatched.

figure 5 shows the end face 23 of the intake manifold 17 on the base panel side. The intake opening 27 provided by the intake manifold 17 at the front can be seen, with the cross-sectional area 24 provided by the intake opening 27 being shown hatched.

figure 6 shows the spaced-apart arrangement of intake manifold 17 and base panel 15 in a schematic side view, with a gap space 28 being provided between base panel 15 and the end face 23 of intake manifold 17 .

The gap size X structurally determines the admixture ratio of circulated process air to ambient air drawn in. The proportion of circulated process air is preferably between 25% and 75%, with the proportion of ambient air preferably being between 75% and 25%.

wobei α zwischen 5 mm und 25 mm, noch mehr bevorzugt zwischen 12 mm und 18 mm beträgt.Structurally, the gap dimension X results as a function of the cross-sectional areas 22 and 24, specifically according to the formula $$\mathrm{X}=\mathrm{Cross\; sectional\; area}22:\mathrm{Cross\; <figure-callout\; id="24"\; label="sectional\; area"\; filenames="imgf0005.png"\; state="\{\{state\}\}">sectional\; area</figure-callout>}24\cdot \mathrm{a},$$

where α is between 5 mm and 25 mm, more preferably between 12 mm and 18 mm.

To promote the inflow of the bypass flow 20, the recess 16 in the screen 15 is equipped with air guide elements 25 on the intake port side. This can be, for example, an annular design that surrounds the recess 16 all the way around.

The Figures 9, 10 and 11 reveal different embodiments in this context. while showing figure 9 a recess 16 without air guide elements 25 on the intake manifold side.

In contrast to the design figure 9 shows figure 11 an embodiment with a recess 16, which has a ring-shaped air guiding element 25 on the outlet connection side. figure 10 shows a recess 16 having a plurality of openings, each opening being equipped with a respective air guiding element 25 on the intake connection side, as is also the case in FIG figure 6 illustrated embodiment shows.

The Figures 7 and 8 reveal different embodiments of the design of the recess 16. while showing figure 7 a simple recess 16 in the form of an opening. figure 8 shows an embodiment according to which the recess 16 is blocked by a ribbing 21 . This ribbing 21 has the advantage that it can serve as a support for safety devices for the fan 10, such as screens or the like. <b>Reference marks</b> 1 dishwasher 18 Part of the cooling air flow 2 Housing 19 ambient air 3 flush tank 20 bypass flow 4 dishwashing room 21 rib 5 loading opening 22 Cross sectional area 6 scullery door 23 face 7 countertop 24 Cross sectional area 8th cooling airflow 25 air deflector 9 base 26 process air 10 fan 27 intake port 11 Housing 28 gap space 12 impeller 29 axis of rotation 13 engine X gap size 14 Condensation drying device 15 plinth panel 16 recess 17 intake manifold

Claims (11)

1. Method for carrying out a drying program portion in a dishwasher (1), in particular a domestic dishwasher, comprising a washing container (3) which has a loading opening (5) on its front side for loading with washware to be cleaned, which loading opening can be closed in a fluid-tight manner by means of a pivotably mounted washing chamber door (6), and comprising a condensation drying device (14) which has a fan (10) for generating a cooling air flow (8),

   the cooling air flow (8) being guided past the washing container (3) on the outside thereof,

   a first part (18) of the cooling air flow (8) being guided along a portion of the underside of a worktop (7) arranged above the washing container (3), characterized in that a second part of the cooling air flow (8) is circulated in a bypass flow (20) and is guided past the outside of the washing container (3) and sucked in again as process air by the fan, such that the cooling air flow (8) results as a mixture of ambient air (19) and process air (26) guided past the outside of the washing tank (3) in the bypass flow (20).
2. Dishwasher for carrying out the method according to claim 1, comprising a washing container (3) which has a loading opening on its front side (5) for loading with washware to be cleaned, which loading opening can be closed in a fluid-tight manner by means of a pivotably mounted washing chamber door (6), and comprising a condensation drying device (14) which has means (10) for generating a cooling air flow (8), the means for generating a cooling air flow (8) being a fan (10) which is arranged in a base (9) below the washing container (3), the base (9) having a recess (16) formed in a frontal baseplate (15) for sucking in ambient air (19) through the fan (10), to which recess the fan (10) is fluidically connected by means of a suction nozzle (17), characterized in that the suction nozzle (17) is arranged with its end face (23), which faces the base plate (15) and provides a suction opening (27), spaced apart from the base plate (15) thus leaving a gap (28).
3. Dishwasher according to claim 2, characterized in that the cross-sectional area (24) of the suction opening (27) of the suction nozzle (17) and the cross-sectional area (22) of the recess (16) in the base plate (15) are oriented so as to be mutually parallel.
4. Dishwasher according to either claim 2 or claim 3, characterized in that the cross-sectional area (24) of the suction opening (27) of the connection nozzle (17) is between 20 cm²and 70 cm², preferably between 30 cm²and 60 cm², even more preferably between 40 cm²and 50 cm².
5. Dishwasher according to any of the preceding claims 2 to 4, characterized in that the cross-sectional area (22) of the recess (16) in the base plate (15) is between 20 cm²and 70 cm², preferably between 30 cm²and 60 cm², even more preferably between 40 cm²and 50 cm².
6. Dishwasher according to any of the preceding claims 2 to 5, characterized in that the gap dimension X between the base plate (15) and the end face (23) of the suction nozzle (17) is between 4 mm and 12 mm, preferably between 6 mm and 10 mm, even more preferably between 7 mm and 9 mm.
7. Dishwasher according to any of the preceding claims 2 to 6, characterized in that the gap dimension X results as a function of the ratio of the cross-sectional area (22) of the recess (16) in the base plate (15) to the cross-sectional area (24) of the suction opening (27) of the suction nozzle (17), specifically as X = cross-sectional area (22) / cross-sectional area (24) * α, where α is between 5 mm and 25 mm, preferably between 12 mm and 18 mm.
8. Dishwasher according to any of the preceding claims 2 to 7, characterized in that the cross-sectional area (22) of the recess (16) in the base plate (15) is blocked.
9. Dishwasher according to claim 8, characterized in that the blocking is formed by ribs (21).
10. Dishwasher according to any of the preceding claims 2 to 9, characterized in that the recess (16) provided by the base plate (15) is equipped with an air guide element (25) on the suction nozzle side.
11. Dishwasher according to claim 10, characterized in that the air guide element (25) is an air guide ring surrounding the recess (16).

Images