EP3473156B1 - Dishwasher - Google Patents

Description

The invention relates to a dishwasher according to claim 1. The invention also relates to a method for introducing fresh water into a dishwasher, in which the fresh water is supplied to the dishwasher from a fresh water discharge point.

Dishwashers with a washing compartment that provides a washing space and is used to hold items to be cleaned, a collection pot into which the washing container flows, a spray arm arranged inside the washing compartment for applying washing liquid to items to be cleaned, and a circulating pump, the spray arm being connected to the Circulation pump is fluidically connected are well known from the prior art, which is why separate printed evidence is not required at this point.

Previously known dishwashers have a washing compartment that provides a washing space. This is accessible to the user via a loading opening which can be closed in a fluid-tight manner by means of a pivotably mounted washing compartment door. When used as intended, the washing container is used to hold items to be cleaned, which can be crockery, cutlery and/or the like, for example.

In order to apply washing liquid, the so-called washing liquor, to the items to be washed to be cleaned, the dishwasher has a spray device in the interior of the washing compartment. This spray device typically provides rotatably mounted spray arms, with two or three such spray arms being provided as a rule. When used as intended, the items to be cleaned are fed with washing liquor by means of rotating spray arms.

The washing liquor released by the spray device during operation hits the items to be cleaned and then collects in a collection pot into which the washing container flows. The collection pot is connected to a circulation pump on the one hand and to a drain pump on the other hand. For loading the spray device with The rinsing liquor is used by the circulating pump which, when used as intended, circulates the rinsing liquid fed into the dishwasher. At the end of a washing program, the washing liquid is pumped out using the drain pump and discarded.

At the start of a washing program, fresh water is supplied to the dishwasher from a fresh water delivery point. For this purpose, the collection pot of the dishwasher has a fresh water inlet which is fluidically connected to the fresh water discharge point, for example by means of a hose. As soon as the collection pot is filled with enough fresh water for proper operation of the circulating pump, the circulating pump is put into operation, as a result of which the spray arms of the spray device are charged with washing liquor.

the EP 3181033 A1 and the WO2017/114558 A1 disclose in each case a dishwasher with a circulating pump and water distribution device, with which the circulated washing liquor can optionally be directed to a plurality of feed pipes leading to different spray devices. In a feed pipe there is a leakage opening which closes as a function of the flushing pressure and which assumes an open state when there is no application of washing liquor, so that the water present in the feed pipe can escape through the leakage opening.

the U.S. 2008/0142056 A1 discloses a dishwasher with an upper spray arm arranged on a washing basket and with a piece of pipe on the spray arm and a movably arranged connection piece of a supply pipe on the machine side. The fluid-technical connection between the connection piece and the pipe section is closed by the pressure of the washing liquid. Due to the design, even after the washing liquid has been pumped out as intended by means of the drain pump at the end of a washing program, a residual amount of washing liquid that cannot be pumped away remains in the pump housings of the circulation pump and drain pump, in the collection pot and in the lines for the formation of fluidic connections between the collection pot and the circulating pump on the one hand and the collection pot and the drain pump on the other hand. If an intended washing program is now started by introducing fresh water, then the fresh water is mixed with the residual washing liquor still present in the dishwasher. This leads to an unintentional entrainment of caustic and/or chlorides in the newly started dishwashing program. Disadvantageously, it can lead to corrosion, both on dishwasher-side components, such as the heating device, the pump housings, the supply lines and/or the like, as well as the items to be cleaned.

In order to counteract such alkali and / or chloride carryover, it is from the EP 2 759 244 B1 It is known to introduce fresh water into the dishwasher for flushing, in particular, the circulating pump and the collection pot, after the washing items have been cleaned as intended. The beats EP 2 759 244 B1 before introducing fresh water on the pressure side of the circulating pump into this, with the circulating pump switched off, i.e. without a pump. The fresh water fed into the circulating pump flows through the circulating pump and from there it goes directly to the collecting tank via the corresponding connecting lines. From here, a discharge can take place by switching on the drain pump. As a result of the introduction of fresh water, the residual washing liquor in the dishwasher is not only merely mixed with the fresh water, but the remaining washing liquor is largely expelled by displacement. Almost complete disposal of the residual wash liquor can thus be achieved with comparatively little fresh water, so that as far as possible no alkali and/or chloride residues are carried over into a subsequent wash program.

Although after the EP 2 759 244 B1 previously known design has proven itself in everyday practical use, there is a need for improvement, in particular with regard to a simplified structure of the dishwasher. It is therefore the object of the invention to further develop a generic dishwasher to the effect that flushing of the suds and/or chloride line is made possible with a reduced structure on the machine side.

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

In addition, on the process side, a method for introducing fresh water into a dishwasher is proposed, in which fresh water is supplied to the dishwasher from a fresh water delivery point, the fresh water being fed to a circulating pump on the suction side, preferably the suction mouth side, and from there by means of the circulating pump into a fluidically connected to the circulating pump collection pot is pumped, with the fresh water fed to the circulating pump being fed to the collection pot via a leakage opening in a spray arm and/or in a fluidic connection between the circulating pump and a spray arm, which is open towards a washing chamber and/or towards the collection pot and closes depending on the pressure of the washing liquor.

A leakage opening is provided according to the invention. This leakage opening is provided by the spray arm and/or is formed in the fluidic connection between the circulation pump and the spray arm. If the suds and/or chloride line is flushed, the water supplied to the dishwasher is routed via this leakage opening and introduced into the washing compartment and/or the collection pot. In this way, the caustic and/or chloride line can be flushed completely without additional machine-side parts.

According to the invention, the leakage opening is designed so that it closes as a function of the washing liquor pressure. This results in a sealed leakage opening in the intended operating case of carrying out a flushing program. The construction according to the invention thus ensures that the leakage opening is only open when fresh water is introduced below a certain pressure level, which is typically the case when fresh water is introduced for the purpose of flushing the lye and/or chloride line. When a washing program is carried out as intended, a pressure above this pressure level develops in the circulated washing liquid, which leads to the leakage opening being automatically closed.

The configuration according to the invention also has the advantage of a very short distance in the case of flushing. The fresh water fed to the circulating pump goes directly to the fluidic connection between the circulating pump and the spray arm, so that there is a comparatively short return flow path into the collection pot via the leakage point provided according to the invention. In this respect, the configuration according to the invention is suitable not only for the case of flushing through the caustic and/or chloride path, but also for other applications in which the shortest possible path is preferred. In this context, mention should be made, for example, of washing liquor heating by means of a heating device integrated in the circulating pump. In this case, a comparatively rapid washing liquor heating be achieved in that the washing liquor is guided through the leakage opening provided according to the invention, which, in the manner already described above, requires a comparatively short route.

In a departure from the prior art, the fresh water inlet is not on the pressure side but on the suction side of the circulating pump. On the process side, therefore, the lye and/or chloride line is flushed through by using the circulating pump, that is to say, in contrast to the prior art, not without a pump.

The suction-side connection to the circulating pump is preferably formed in the region of the suction mouth of the circulating pump, that is to say on the suction-mouth side. The "suction mouth side" design of the fresh water inlet in the context of the invention means that in normal operation, fresh water is fed directly into the circulating pump without the incoming fresh water getting into other areas of the collection pot. A design on the suction mouth side in this sense is present in particular when the fresh water inlet is designed within the fluidic connection between the collection pot and the circulating pump.

In the intended use case, the circulating pump is therefore acted upon by fresh water, which is then circulated by means of the circulating pump when the circulating pump is switched on. If the lye and/or chloride line is to be flushed, the fresh water introduced into the dishwasher and fed to the circulating pump is fed to the spray arm which is fluidically connected to the circulating pump. However, unlike in normal flushing operation, there is no spray arm actuation, because the fresh water exits through the leakage opening provided according to the invention and flows into the collecting pot, either directly or with the flushing chamber interposed, depending on the design of the leakage opening. In any case, fresh water flows through the pump housing of the circulating pump, the flow connection to the spray arm and the collection pot, which leads to the removal of any lye and/or chloride residues. When a drain pump which is also fluidically connected to the collection pot is switched on, the fresh water arriving in the collection pot is pumped out, which also cleans the pump housing of the drain pump and the fluidic connection between the collection pot and the drain pump.

The configuration according to the invention allows the lye and/or chloride section, i.e. the circulating pump, the collecting pot and the line path leading from the circulating pump via the collecting pot to the drain pump, to be flushed through completely, so that residual liquids located there can be expelled as far as possible, so that no unwanted lye and/or carry over of chloride into a subsequent washing program. In this case, the circulating pump is charged with fresh water via the suction side, which means that flushing does not take place without a pump, but rather during pump operation. However, the fresh water delivered by the circulation pump on the pressure side is not delivered via the spray nozzles of the spray arm which is fluidically connected to the circulation pump, but via a leakage opening. In this respect, in the case of rinsing, there is no intended operation of the spray arm, as is the case when a rinsing program is carried out. The leakage opening is either provided by the spray arm or it is formed in the fluidic connection between the circulation pump and the spray arm. Alternatively, several leakage openings can also be provided, in which case both the spray arm and the fluidic connection between the circulating pump and the spray arm can have corresponding leakage openings.

The configuration according to the invention is compared to the known construction according to the EP 2 759 244 B1 particularly advantageous with regard to two aspects. On the one hand, the construction effort on the machine side is reduced. Only one fresh water inlet is required, which is designed on the suction side of the circulating pump. Fresh water is fed in via this fresh water inlet, both in the washing program case and for the purpose of flushing according to the method according to the invention. In this respect, in departure from the construction after the EP 2 759 244 B1 no additional line paths including corresponding blocking and / or actuators required. Furthermore, the design of a leakage opening according to the invention does not require any additional line paths and/or the like. An overall simplified structure of the dishwasher is thus achieved, which simplifies production and thus makes it less expensive.

On the other hand, the configuration according to the invention enables the process to be carried out more effectively in terms of the flushing result. This is because the construction according to the invention requires that fresh water introduced into the circulating pump on the suction side is pumped through the leakage opening into the washing chamber and/or the collection pot, depending on whether the leakage opening is provided by the spray arm or is formed in the fluidic connection between the circulation pump and the spray arm. In any case, however, the discharge of the fresh water via the leakage opening means that the collection pot is not charged with fresh water via a lateral access, in contrast to the configuration according to the prior art, but rather from above with the interposition of the leakage opening. This advantageously leads to the fact that, due to the density differences between fresh water and residual water, there is an increased displacement of residual water by the fresh water introduced compared to the prior art. This also contributes overall to an improved process result.

At the beginning of the implementation of the method according to the invention, the suction side of the circulating pump is charged with fresh water from the fresh water delivery point. The circulating pump is switched on at the same time as the fresh water is applied or at a later time. It is preferred to switch on the circulating pump before the fresh water is introduced, in order to prevent parts of the fresh water introduced from being able to flow into the collection pot when the circulating pump is switched off

The introduced fresh water is sucked in when the circulating pump is switched on and brought to the pressure side of the circulating pump, where it reaches the fluidic connection to the spray arm, which spray arm is preferably the lower spray arm. This is because the fluidic connection to the lower spray arm is routed through the collection pot.

According to a first alternative of the invention, the spray arm has the leakage opening. According to this embodiment, the fresh water fed to the fluidic connection between the circulating pump and spray arm reaches the leakage opening on the spray arm side, where it exits and then collects on the bottom side of the washing container, from where it flows into the collection pot that is fluidically connected to the washing container. This is where the residual water that may still be in the collection pot is displaced or the fresh water is mixed with the residual water. Preferably before or at the latest when the circulating pump is switched on, the drain pump is also switched on, so that with or at the latest when the fresh water conveyed by the circulating pump is introduced into the collecting pot, the lye- and/or chloride-loaded water is pumped out residual water takes place.

According to an alternative embodiment, it is provided that the leakage opening is provided by the fluidic connection between the circulation pump and the spray arm. According to this embodiment, the spray arm is not loaded. The fluidic connection between the circulating pump and the spray arm, which is routed through the collection pot, releases much more fresh water through the leakage opening before it can reach the spray arm. Consequently, without the rinsing tank being interposed in terms of flow technology, fresh water is applied directly to the collection pot. In the manner already described above, the residual water that may be present in the collection pot can then be pumped out by switching on the drain pump. The fluidic connection between the circulating pump and the spray arm is preferably guided through the collection pot, in particular along the collection pot axis, with the leakage opening being arranged in the region of the collection pot, in particular inside or above the collection pot.

The construction according to the invention is suitable not only in the manner already described above for effecting flushing of the lye and/or chloride line. Rather, the flow circuit provided in the design can also be used to heat the fresh water fed into the dishwasher in the most time-optimized manner possible, for example by means of a heater integrated in the circulation pump. In this case, pumping out by means of the drain pump would not take place. Rather, the fresh water introduced would continue to be circulated by means of the circulating pump until the desired target temperature is reached.

The leakage opening provided according to the invention closes as a function of the pressure of the washing liquor. It is thus possible to distinguish between flushing operation on the one hand and flushing program operation on the other. In the flushing mode, the circulating pump is only operated at a low speed, for example at idle speed. At such a low speed, there is only a low pump pressure, which keeps the leakage opening open. Fresh water can then be discharged via the leakage opening in the manner already described above. During the execution of a washing program, the circulation pump is operated at a higher speed, which leads to a higher pump pressure. As a result, the flushing water pressure-dependent leakage opening closes, so that a flushing program can be carried out as intended can take place without flushing water flowing out via a leakage opening that is still open.

In this context, according to a further feature of the invention, it is proposed that the spray arm has an inlet opening for washing water, into which a bearing bush is inserted in an axially displaceable manner, the bearing bush providing a sealing surface which interacts with a contact surface surrounding the inlet opening, the spray arm and the bearing bush can be arranged at a distance from one another, leaving a gap space between the sealing surface and the contact surface that provides the leakage opening.

According to this embodiment, a bearing bush inserted into an inlet opening of the spray arm is provided. The spray arm and the bearing bush are arranged so that they can be displaced axially in relation to one another. In the final assembled state, the bearing bush is fixed in position at the end of a pipe socket. The spray arm can therefore move in the axial direction in relation to the bearing bush and thus also to the pipe socket on which the bearing bush is arranged.

With the corresponding pressure of the fresh water entering the spray arm via the pipe socket, the spray arm lifts in relation to the bearing bush in the vertical direction, whereby the sealing and contact surfaces are pressed against one another. This leads to a sealing of the spray arm relative to the bearing bush, so that an unintentional escape of washing liquor between the bearing bush and the spray arm is prevented. The washing liquor fed to the pipe socket and thus also to the spray arm exits as intended via the nozzles provided by the spray arm, so that an intended wash program can be run through.

When the washing water pressure is low, the spray arm moves downwards in relation to the bearing bush, following the weight, so that due to the then spaced arrangement of the bearing bush and spray arm, a gap is created between the sealing surface on the one hand and the contact surface on the other. This gap provides the above-described leakage opening, so that flushing water introduced via the pipe socket can flow through the gap between the sealing surface and the contact surface and can flow off in the direction of the collection pot.

In a structurally simple manner, the formation of a leakage opening that closes as a function of the rinsing fluid pressure is realized.

According to a further feature of the invention, the bearing bushing has a sleeve-shaped bushing body and a radial web which is arranged on one end and surrounds the bushing body all the way round and which provides the sealing surface facing away from the spray arm, the radial web having an end-side outer contour which is designed to deviate from the circular shape.

The design of the outer contour of the radial web of the bearing bush, which deviates from the circular shape, avoids unwanted seals, which ensures the formation of a leakage opening with a correspondingly low washing liquor pressure.

According to a further feature of the invention, the outer contour of the radial web can be polygonal, slot-shaped recesses being preferred. Other geometric configurations are also conceivable, the only thing that is important according to the invention is to avoid unwanted front-side seals between the bearing bush and the spray arm for the purpose of forming a leakage opening.

According to a further feature of the invention, it is provided that the bearing bush interacts with a union nut for arrangement on a pipe socket, the union nut having recesses and/or indentations on the spray arm side. These recesses and/or indentations on the side of the union nut also serve to be able to reliably provide a flow path for forming a leakage opening with a correspondingly low washing liquor pressure.

In an alternative embodiment of the invention, it is provided that the spray arm is arranged at one end of a pipe socket, which has two pipe sections that are axially displaceable relative to one another, each of which has an opening formed in the respective pipe wall, the pipe sections being axially aligned with one another, forming an at least regionally and the overlapping of the two openings providing the leakage opening can be arranged.

According to this embodiment, a pipe socket that is guided through the collection pot is provided, which is part of the fluidic connection between the circulating pump and the spray arm is. The pipe socket is designed to be telescopic and has two pipe sections which are arranged so as to be axially displaceable with respect to one another. With a corresponding speed of the circulating pump, ie with a corresponding washing liquor pressure, these two pipe sections, which are axially displaceable relative to one another, are moved apart in the vertical direction. When the pressure drops, the upper of the two pipe sections moves back down following the weight.

The two telescopic pipe sections have openings in the respective pipe wall. In the extended state of the two pipe sections, the openings are not brought into overlap. In this position, the water fed into the pipe socket is fed to the spray arm in a manner known per se.

When the pressure of the washing liquor is below a certain limit value, the upper of the two pipe sections moves downwards in relation to the lower pipe section as a result of the weight force, as a result of which the openings provided by the pipe sections overlap. This creates a leakage opening through which the fresh water fed into the pipe socket can escape and flow directly into the collection pot. The leakage opening is located in the area of the collection pot, in particular inside or directly above the collection pot.

This alternative configuration also proves to be very simple in terms of construction in an advantageous manner, and it is also not very susceptible to faults.

According to a further feature of the invention, it is provided that the circulating pump is connected to the collection pot with the fluidic interposition of a pipe socket providing a suction mouth. This pipe socket represents the suction port for the circulating pump. According to a special feature of the invention, it is now provided that the pipe socket connected to the fluidic connection between the circulating pump and the collection pot has the fresh water inlet. In this case, the fresh water inlet can be designed as a connecting piece formed on the pipe socket, onto which the line for supplying fresh water is plugged. This type of constructive design proves to be particularly simple in terms of production, since the collection pot together with the pipe socket and the connection socket arranged thereon can be designed as a one-piece injection molded part.

According to a further feature of the invention, a bypass line which opens into the collection pot and leads to the pipe socket is provided. This bypass line serves to equalize the pressure during the intended execution of a washing program.

At the beginning of a washing program, fresh water is supplied to the dishwasher in a manner known per se via the fresh water inlet. As soon as the amount of fresh water required for proper pump operation has been introduced into the dishwasher, the circulation pump is started up, as a result of which fresh water circulation within the dishwasher is as intended. During such a circulating operation, a negative pressure is formed on the suction side of the circulating pump. Since the fresh water inlet is formed on the suction mouth side of the circulating pump, such a negative pressure formation results in the circulating pump drawing air from the fresh water inlet line. This disturbs the proper operation of the circulation pump and should therefore be avoided. According to the invention, therefore, a bypass line is provided which is fluidically connected to the collection pot. In the event of negative pressure, air is thus prevented from being sucked in from the fresh water supply line.

Fig. 1

in schematischer Ansicht eine erfindungsgemäße Geschirrspülmaschine;

Fig. 2

in schematischer Prinzipdarstellung eine erfindungsgemäße Geschirrspülmaschine;

Fig. 3

in schematischer Prinzipdarstellung eine erste Ausführungsform der erfindungsgemäßen Geschirrspülmaschine;

Fig. 4

in schematischer Prinzipdarstellung eine zweite Ausführungsform der erfindungsgemäßen Geschirrspülmaschine;

Fig. 5

in teilgeschnittener Seitenansicht die Anordnung eines Sprüharms an einem Rohrstutzen gemäß erster Ausführungsform nach Fig. 3;

Fig. 6

eine Detailansicht gemäß einem Ausschnitt nach Fig. 5;

Fig. 7

eine Detailansicht gemäß einem Ausschnitt nach Fig. 6;

Fig. 8

in schematischer Perspektivdarstellung ausschnittsweise einen Sprüharm;

Fig. 9

in schematischer Perspektivdarstellung eine Überwurfmutter;

Fig. 10

in schematischer Perspektivansicht eine Lagerbuchse;

Fig. 11

in schematischer Seitenansicht die Ausbildung eines Rohrstutzens gemäß der zweiten Ausführungsform nach Fig. 4 in einer ersten Stellung; und

Fig. 12

in schematischer Seitenansicht die Ausbildung eines Rohrstutzens gemäß der zweiten Ausführungsform nach Fig. 4 in einer zweiten Stellung.

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

1

a schematic view of a dishwasher according to the invention;

2

a schematic representation of the principle of a dishwasher according to the invention;

3

in a schematic representation of the principle of a first embodiment of the dishwasher according to the invention;

4

in a schematic representation of the principle of a second embodiment of the dishwasher according to the invention;

figure 5

in a partially sectional side view, the arrangement of a spray arm on a pipe socket according to the first embodiment 3 ;

6

a detailed view according to a section figure 5 ;

7

a detailed view according to a section 6 ;

8

in a schematic perspective view of a detail of a spray arm;

9

in a schematic perspective view of a union nut;

10

in a schematic perspective view of a bearing bush;

11

in a schematic side view of the formation of a pipe socket according to the second embodiment 4 in a first position; and

12

in a schematic side view of the formation of a pipe socket according to the second embodiment 4 in a second position.

1 shows a dishwasher 1 according to the invention in a purely schematic representation.

The dishwasher 1 has a housing 2 which, among other things, accommodates a washing container 3 . The rinsing container 3 in turn provides a rinsing chamber 4 which, when used as intended, serves to accommodate items to be washed to be cleaned.

A spraying device 5 , which is arranged inside the washing container 3 , is used to supply washing items to be cleaned with washing liquor. Preferably, such a spray device 5 has spray arms 6 and 7 which are each arranged rotatably inside the washing container 3 . In the exemplary embodiment shown, the spray device 5 has an upper spray arm 6 and a lower spray arm 7. Typically, a generic dishwasher has three spray arms, namely an upper and a lower spray arm and a middle spray arm.

The rinsing compartment 3 is accessible to the user via a charging opening 8 which can be closed in a fluid-tight manner by means of a pivotably mounted rinsing chamber door 9 .

The washing compartment 3 or the washing chamber 4 provided by the washing compartment 3 opens into a figure 5 Collection pot 10 shown in more detail. A circulation pump 11 and a drain pump 12 are each fluidly connected to this collection pot 10 . For this purpose, a fluidic connection 15 is formed between the circulation pump 11 and the collecting pot 10 and a fluidic connection 13 is formed between the drain pump 12 and the collecting pot 10 .

The circulation pump 11 is connected to the spray arms 6 and 7 of the spray device 5 via corresponding fluidic connections 16 and 17, with the fluidic connection 16 from the circulation pump 11 to a lower spray arm 7 and the fluidic connection 17 from the circulation pump 11 to an upper spray arm 6 leads. In a manner known per se, there can of course be at least one additional spray element, not shown here, in particular an additional upper spray arm, for example a middle spray arm, which can be connected to the circulating pump 11 via a separate supply line.

When used as intended, the circulating pump 11 can feed rinsing liquid into either the fluidic connection 16 leading to the lower spray arm 7 or the fluidic connection 17 leading to the upper spray arm 6 .

After completion of a wash program, the used wash water is pumped out by means of the drain pump 12, for which purpose the drain pump 12 is connected to a line 14, which typically opens into the public sewage system and is discharged via the used wash water in accordance with the arrow 18.

2 shows the further construction of the dishwasher 1 according to the invention. After that, a fresh water discharge point 26 is provided, which can be, for example, access to the public water network, also with the interposition of a machine-side water reservoir and/or the like. What is decisive is that fresh water is supplied via the fresh water delivery point 26 with the fresh water line 21 interposed. In the exemplary embodiment shown, a check valve 22 and a fresh water softening device 24 are also provided. When used as intended, fresh water from the fresh water delivery point 26 therefore flows over the line 25 to the fresh water softening device 24 and from there via the line 23 to the valve 22, which separates the line 23 from the fresh water line 21. In the intended use case, the check valve 22 is open, so that fresh water can get into the fresh water line 21 via the line path described above.

The fresh water line 21 is divided into a first supply line 49 and a second supply line, which represents a bypass line 27 that will be described in more detail below. The first supply line 49 opens into the fluidic connection 15 between the collection pot 10 and the circulating pump 11 , ie the fresh water inlet 20 is formed on the suction side of the circulating pump 11 . In normal operation, the circulating pump 11 is therefore directly charged with fresh water via the fresh water line 21 or the first supply line 49 connected to the fresh water line 21.

At the beginning of a washing program, fresh water is fed to the circulating pump 11 via the supply line 49 . As soon as a sufficient amount of fresh water has been supplied, the circulating pump 11 is put into operation and the supplied fresh water is circulated, with the circulating pump 11 being activated via the fluidic connection 17, in particular optionally or alternately, either the upper spray arm 6 or via the fluidic connection 16 the lower spray arm 7 supplied with fresh water. As a further alternative, a third, in particular middle, spray arm (not shown) can preferably also be supplied with fresh water via a further supply line. The fresh water fed into the washing compartment 3 in this way is used for washing dishes and collects as washing liquor in the collection pot 10, from where the washing liquor is then fed back to the circulation pump 11 via the fluidic connection 15 and is thus kept in circulation.

After the end of a washing program that has been carried out as intended, there are lye and chloride residues, in particular in the collection pot 10 and in the housing of the circulation pump 11, which must be removed in order to avoid carryover to a subsequent program step and/or a subsequent washing program. According to the invention, it is therefore provided that flushing takes place, with which the lye and/or chloride section is cleaned, that is to say in particular the collection pot 10 and the housings of the pumps 11 and 12 are freed from lye and/or chloride residues.

The flushing according to the invention provides that the dishwasher 1 is supplied with fresh water from a fresh water discharge point 26 in the manner already described above. The fresh water is fed to the circulation pump 11 on the suction mouth side and pumped from there by means of the circulation pump 11 into the collection pot 10 which is fluidically connected to the circulation pump 11 . The drain pump 12 fluidically connected to the collection pot 10 is operated at least temporarily at the same time as the circulating pump 11, so that the mixed water from fresh and residual water that collects in the collection pot 10 is pumped out.

Such rinsing takes place with a fresh water quantity of, for example, 150 ml. Such a small quantity of water is already sufficient to free the lye and/or chloride line from undesired lye and/or chloride residues as far as possible. Alternatively, more fresh water can be used for rinsing and/or the rinsing step can be repeated several times, for example five times, which leads to a total fresh water consumption of 750 ml at 150 ml per rinsing cycle.

A particular advantage of carrying out the method according to the invention is, inter alia, that only the caustic and/or chloride section to be cleaned is charged. Fresh water is not applied to the washing compartment 3 and/or to the items to be washed that may be located there, as occurs during the intermediate wash in a conventional program sequence. This has the advantage that there is virtually no heat discharged from the dishwasher 1, so that less energy is required to reheat the washing liquor in subsequent washing program steps. Carrying out the method according to the invention makes it possible to completely dispense with a conventional washing program step of intermediate washing, but at the same time to ensure that unwanted alkali and/or chloride residues are removed and not carried over to a subsequent washing program step and/or a subsequent washing program.

According to the invention, a leakage opening 29 is provided for transferring fresh water into the collection pot 10 for the purpose of flushing the caustic and/or chloride line provided, which is open to the washing chamber 4 and/or the collection pot 10 and which closes as a function of the pressure of the washing liquor. The Figures 3 and 4 an embodiment can be seen in each case, which illustrates the formation of such a leakage opening 29 .

According to the first embodiment 3 the lower spray arm 7 has such a leakage opening 29. In the event of flushing, fresh water from the circulation pump 11 reaches the spray arm 7 via the flow connection 16, which runs along the axis of the collecting pot Spray arm 7, but discharged via the leakage opening 29 provided by the spray arm 7. From there, the fresh water then reaches the collecting pot 10 in accordance with the arrows 28, which in the manner already described above leads to a displacement of the residual water located there or to a mixing with the residual water located there.

A second embodiment is in 4 shown. It is then provided that a pipe socket 39, which is part of the fluidic connection 16, provides the leakage opening 29, via which fresh water pumped by the circulating pump 11 is discharged in accordance with the arrow 28 when used as intended. In this respect, too, the residual water in the collection pot 10 is expelled or fresh water and residual water are mixed.

The structural design of the embodiment 3 is in the further Figures 5 to 10 shown in more detail.

The fluidic connection 16 between the circulation pump 11 and the lower spray arm 7 includes, among other things, a pipe socket 39, as can be seen from the illustration figure 5 results. This pipe socket 39 carries the spray arm 7 at the end. When used as intended, fresh water reaches the lower spray arm 7 via the pipe socket 39.

The lower spray arm 7 has a base body 30 on which two spray arm branches 31 are arranged, as is shown in particular in the illustration 8 reveals. The base body 30 provides an inlet opening 32, via which the washing liquor circulated by the circulating pump 11 in the intended use case into the spray arm 7 flows in.

A union nut 40 is used to arrange the spray arm 7 on the pipe socket 39, as is shown in particular in FIG figure 5 reveals. The union nut 40 interacts with a bearing bush 33 which is inserted into the inlet opening 32 of the base body 30 of the lower spray arm 7 .

10 shows the bearing bush 33 in a detailed view. As can be seen from this representation, the bearing bushing 33 has a bushing body 36. This carries at one end a circumferentially formed radial web 37. This radial web 37 carries with reference to the plane of the drawing 10 underside a sealing surface 34, which is formed facing away from the spray arm in the final assembled state.

The radial web 37 has a front-side outer contour 38 which is designed to deviate from the circular shape. According to the illustrated embodiment 10 37 notch-like recesses 26 are formed on the outside of the radial web.

In the final assembled state, the bearing bushing 33 is inserted into the inlet opening 32 of the lower spray arm 7 so that it can be displaced in the axial direction, with the bearing bushing 33 being arranged on the pipe socket 39 in a position-fixed manner by means of the union nut 70 . The axial displaceability between the bearing bush 33 and the lower spray arm 7 therefore causes the lower spray arm 7 in the height direction 47, which with respect to the plane of the drawing, for example, according to figure 5 can move up or down in relation to the bearing bush 33 or in relation to the pipe socket 39.

If the lower spray arm 7 rests on the union nut 40 due to the force of gravity, then the radial web 37 of the bearing bush 33 and the associated counter-contour of the lower spray arm 7 are arranged at a distance from one another, leaving a gap space. This fact emerges in particular from a synopsis of the figures 6 and 7 .

The resulting due to the spaced arrangement of bearing bush 33 on the lower spray arm 7 gap represents the leakage opening 29 according to the invention figures 6 and 7 drawn arrows flow and according to the arrows 28 after 3 can flow into the collection pot 10.

If the circulating pump 11 is actuated at a sufficient speed during the intended flushing operation, it delivers fresh water at a correspondingly high pressure through the pipe socket 39 into the lower spray arm 7. When pressure is applied in this way, the lower spray arm 7 is moved upwards against the weight acting on it, i.e relative to the bearing bush 33, which is arranged in a secure position on the pipe socket 39 by means of the union nut 40. As a result of such a displacement movement of the lower spray arm 7, the contact surface 35 provided by the lower spray arm 7 comes to rest on the correspondingly configured sealing surface 34 of the bearing bushing 33, with the result that the leakage opening 29 is closed. Washing liquid introduced into the lower spray arm 7 during the execution of an intended washing program cannot therefore be discharged via the leakage opening 29, since this is closed at the top as a result of the pressure-related movement of the lower spray arm 7.

9 shows the union nut 40 in a detailed view. As can be seen from this illustration, the union nut 40 has recesses 41. These recesses 41 and the recesses 46 provided by the bearing bush 33 support the formation of a leakage opening 29 according to the invention, as can be seen in particular from the detailed views according to FIGS figures 6 and 7 results.

The constructive implementation of the embodiment 4 lets the Figures 11 and 12 remove. As can be seen from these illustrations, the pipe socket 39 has two pipe sections 42 and 43 which are telescopically displaceable in the axial direction. Both pipe sections 42 and 43 each have an opening 44 and 45. With appropriate pressurization of the lower spray arm 7, as is shown in 12 is shown, the lower spray arm 7 is moved up so far that the openings 44 and 45 are not at least partially congruent. However, if the lower spray arm 7 is moved downwards in accordance with the weight acting on it, like this 11 can be seen, the openings 44 and 45 provided by the tube sections 42 and 43 come at least partially into overlap, whereby the leakage opening 29 according to the invention is formed.

As the Figures 3 and 4 can also be seen, the collection pot 10 provides a pipe socket 48 ready. The circulating pump 11 is connected to this pipe socket 48 on the suction side. The pipe socket 48 is therefore part of the fluidic connection 15 between the collection pot 10 and the circulating pump 11.

The pipe socket 48 is equipped with a connection socket, which is not shown in detail in the figures. The first feed line 49 , which opens into the fresh water line 21 , is connected to this. In the intended operating case, the circulating pump 11 can be given fresh water on the suction mouth side, in that fresh water reaches the pipe socket 48 serving as the suction mouth 19 via the lines 21 and 28 and the connection piece. In the circulating mode of a washing program operated as intended, a negative pressure arises in the pipe socket 48 . This leads to air standing in the fresh water line 21 being sucked in, which disrupts the proper operation of the circulating pump 11 . In order to avoid this, the bypass line 27 already mentioned at the outset is provided, as can be seen in particular from the illustration 2 results. Pressure equalization takes place via this bypass line 27 or flushing water in the collection pot 10 can be drawn in.

Reference sign

1

dishwasher

2

Housing

3

flush tank

4

dishwashing room

5

spray device

6

Upper spray arm

7

Lower spray arm

8th

loading opening

9

scullery door

10

collection pot

11

circulation pump

12

drain pump

13

fluidic connection

14

Management

15

fluidic connection

16

fluidic connection

17

fluidic connection

18

Arrow

19

suction mouth

20

fresh water enema

21

fresh water line

22

check valve

23

Management

24

Fresh water softening device

25

Management

26

fresh water delivery point

27

bypass line

28

Arrow

29

leakage opening

30

body

31

spray arm mast

32

intake port

33

bearing bush

34

sealing surface

35

contact surface

36

socket body

37

radial bar

38

outer contour

39

pipe socket

40

union nut

41

recess

42

pipe section

43

pipe section

44

breakthrough

45

breakthrough

46

recess

47

height direction

48

pipe socket

49

supply line

Claims (14)

1. Dishwasher, in particular a domestic dishwasher, comprising a washing container (3) which provides a washing chamber (4) and is used for receiving washware to be cleaned, a collecting vessel (10) into which the washing container (3) opens, a spray arm (7) arranged inside the washing container (3) for applying washing solution to washware to be cleaned, and a circulating pump (11), wherein the spray arm (7) is fluidically connected to the circulating pump (11),

   wherein the fluidic connection (16) between the circulating pump (11) and the spray arm (7) and/or the spray arm (7) has a leakage opening (29) which is open towards the washing chamber (4) and/or towards the collecting vessel (10) and closes depending on the washing solution pressure,

   wherein the spray arm (7) has an inlet opening (32) for washing solution, into which a bearing bush (33) is inserted in an axially displaceable manner, wherein the bearing bush (33) provides a sealing surface (34) which interacts with a contact surface (35) circumferentially surrounding the inlet opening (32), wherein the spray arm (7) and the bearing bush (33) can be arranged at a distance from one another, leaving a gap between the sealing surface (34) and the contact surface (35) that provides the leakage opening (29).
2. Dishwasher according to claim 1,
   characterised in that
   the bearing bush (33) has a sleeve-shaped bush body (36) and a radial projection (37) which is arranged in one piece thereon and circumferentially surrounds the bush body (36) and which provides the sealing surface (34) facing away from the spray arm, the radial projection (37) having an end-side outer contour (38) which is formed differently from the circular shape.
3. Dishwasher according to claim 2,
   characterised in that
   the outer contour (38) of the radial projection (37) is polygonal.
4. Dishwasher according to either claim 2 or claim 3,
   characterised in that
   the outer contour (38) of the radial projection (37) has slot-shaped recesses (46).
5. Dishwasher according to any of the preceding claims,
   characterised in that
   the bearing bush (33) interacts with a cap nut (40) for arrangement on a pipe connection piece (39), the cap nut (40) having recesses (41) and/or depressions on the spray arm side.
6. Dishwasher according to claim 1,
   characterised in that
   the spray arm (7) is arranged at the end of a pipe connection piece (39) which has two pipe portions (42, 43) which are axially displaceable relative to one another and which each have an opening (44, 45) formed in the relevant pipe wall, it being possible for the pipe portions (42, 43) to be arranged in their axial alignment with respect to one another to form an overlap of the two openings (44, 45), at least in regions, which overlap provides the leakage opening (29).
7. Dishwasher according to any of the preceding claims,
   characterised in that
   the circulating pump (11) is connected to the collecting vessel (10) with the fluidic interposition of a pipe connection piece (48) which provides a suction mouth (19).
8. Dishwasher according to claim 7,
   characterised by
   a fresh water inlet (20) which is formed on the suction mouth side of the circulating pump (11).
9. Dishwasher according to claim 8,
   characterised in that
   the pipe connection piece (48) has the fresh water inlet (20).
10. Dishwasher according to claim 9,
    characterised in that
    a bypass line (27) opening into the collecting vessel (10) is provided for the pipe connection piece (48).
11. Dishwasher according to claim 10,
    characterised in that
    a fresh water line (21) is provided for connection to a fresh water delivery point (26), which, on the machine side, is connected to a first supply line (49) and to a second supply line, the first supply line (49) opening into the fresh water inlet (20) and the second supply line forming the bypass line (27).
12. Method for introducing fresh water into a dishwasher (1), in particular a dishwasher (1) according to any of the preceding claims, in which the fresh water is supplied to the dishwasher (1) by a fresh water delivery point (26),
    characterised in that
    the fresh water is fed to a circulating pump (11) on the suction side, preferably on the suction mouth side, and from there is pumped by means of the circulating pump (11) into a collecting vessel (10) which is fluidically connected to the circulating pump (11), the fresh water fed to the circulating pump (11) being supplied to the collecting vessel (10) via a leakage opening (29) in a spray arm (7) and/or in a fluidic connection (16) between the circulating pump (11) and a spray arm (7), which leakage opening is open towards a washing chamber (4) and/or towards the collecting vessel (10) and closes depending on the washing solution pressure.
13. Method according to claim 12,
    characterised in that
    a discharge pump (12), which is fluidically connected to the collecting vessel (10), is operated at least temporarily at the same time as the circulating pump (11), and mixed water consisting of fresh and residual water that collects in the collecting vessel (10) is pumped out.
14. Method according to either claim 12 or claim 13,
    characterised in that
    the circulating pump (11) is operated at an idle speed.

Images