EP3545813B1 - Dishwasher, in particular household dishwasher - Google Patents

Description

The invention relates to a dishwasher, in particular in the form of a household dishwasher, with a washing compartment that provides a washing chamber and is used to hold items to be washed to be cleaned, a collection pot into which the washing compartment flows fluidically, and a circulating pump that is fluidically connected to the collection pot by means of a suction line connected.

Dishwashers of the type described above are well known from the prior art, which is why separate printed evidence is not required at this point. It is therefore only an example of the DE 10 2005 008 987 B3 referred.

Dishwashers of the generic type have a washing compartment that provides a washing area. This rinsing chamber is accessible to the user via a loading opening which can be closed in a fluid-tight manner by means of a pivotably mounted rinsing chamber door. When used as intended, the washing container serves to accommodate items to be cleaned, which in the case of a domestic dishwasher can be, in particular, crockery, cutlery and/or the like.

In order to apply washing liquid, also called washing liquor, to items to be washed that are to be cleaned, the dishwasher has a spray device on the washing chamber side. As a rule, this spray device provides rotatably mounted spray arms, with typically two or three such spray arms being provided. In the case of intended use, the items to be cleaned are subjected to washing liquor by means of rotating spray arms.

For the purpose of supplying the spray arms with washing liquid, a circulating pump is provided which is fluidically connected to the collection pot on the one hand and to the spray arms on the other hand.

In the intended use, the from the spraying device collects dispensed washing liquor in the collection pot, into which the washing tank flows in terms of flow. In circulating operation, the circulating pump conveys the washing liquor accumulating in the collection pot to the spray arms of the spray device, from where the washing liquor is then released onto the items to be washed.

In terms of fluid technology, the collection pot into which the rinsing container flows is separated from the rinsing space provided by the rinsing container by a sieve device. The wash liquor circulated by the circulating pump when used as intended therefore only collects in the collecting pot after it has passed through the sieve device inserted in the collecting pot. Leftover food, dirt particles and/or similar contaminants are held back by the screening device, so that a washing liquor that has been cleaned in this respect by screening is circulated.

A screening device of the previously known type typically has a coarse screen, a fine screen and a flat screen. In the final assembled state, the surface filter comes to rest in a recess in the bottom of the washing compartment that is designed to correspond to the surface filter.

The fine screen of the screening device is typically cylindrical. In normal operation, the flow through the fine screen is from the inside to the outside, so that impurities retained by the fine screen collect on the inside of the cylindrical fine screen and form a so-called filter cake there. As the filter cake grows, the permeability of the fine sieve for the wash water decreases, which prevents the wash program from running as intended. In particular, the fine sieve must therefore be cleaned manually by the user from time to time, which is expensive and is perceived as disadvantageous by the user. If such cleaning is not carried out by the user, the washing result may be inadequate.

Proceeding from the prior art described above, it is the object of the invention to further develop a dishwasher of the type mentioned at the outset in terms of design so that the user can handle the filter device more easily.

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

The circulating pumps typically used according to the state of the art are radial pumps, as is the case with the embodiment according to the one mentioned at the outset DE 10 2005 008 987 B3 . In contrast to this, the invention proposes that an axial pump be used as a circulating pump.

The great advantage of an axial pump compared to a radial pump is that by reversing the direction of rotation of the impeller, it is possible to change the pump delivery direction. An axial pump can therefore be switched from counterclockwise rotation to clockwise rotation and vice versa, which leads to a change in the conveying direction. By means of an axial pump, it is therefore possible, by changing the direction of rotation of the impeller, to drain flushing liquid out of the collection pot or to introduce it into the collection pot.

According to the invention, a second intake line is also provided. By means of this second intake line, the circulating pump designed as an axial pump is fluidically connected to the collection pot. A first intake line and a second intake line are therefore provided in departure from the prior art, with both intake lines forming a fluidic connection of the circulating pump to the collection pot.

As a result of this innovation according to the invention, it is possible to reverse the running direction of the circulating pump, with washing liquor being sucked in from the collection pot either via the first suction line or via the second suction line, depending on the set running direction of the circulating pump.

The possibility created with the construction according to the invention of changing the conveying direction of the circulating pump and thus being able to route the washing liquor flow either via the first or the second suction line offers the advantage of being able to backwash. Such backwashing has the effect that a filter cake formed on the inside of the fine screen is broken up and detached from the fine screen. The filter cake that is detached as a result of such backwashing can then be discharged via the waste water line, which is also connected to the collection pot. As a result, intermediate cleaning of the fine screen by backwashing is possible, which minimizes, if not entirely, the need for manual cleaning of the fine screen by the user completely superfluous. Overall, the configuration according to the invention thus enables simplified handling of the screening device by the user.

A backwash is also from the prior art according to DE 10 2005 008 987 B3 possible. However, the construction described here is very expensive and comparatively complicated in terms of control technology. Because the construction after the DE 10 2005 008 987 B3 requires the use of a separate backwash pump. Accordingly, not only a waste water pump and a circulating pump are provided, but also a backwash pump. Accordingly, there is also a need for complex line routes in order to realize the fluidic connection of all pumps.

The configuration according to the invention is compared to the construction according to the DE 10 2005 008 987 B3 much simpler structure, in particular because a separate backwash pump is not required. Because in the embodiment according to the invention, both the flushing operation and the backflushing operation are handled by one and the same circulating pump. In contrast to the prior art, the structure according to the invention is therefore also very much more compact. In addition, the line paths in the configuration according to the invention are much shorter than in the prior art, which has a favorable effect on water consumption. A minimum fill level within the collection pot is required for proper flushing operation, so that an additional line path inevitably leads to increased water consumption.

Overall, the result of the configuration according to the invention is that the fine filter of the screening device can be backwashed in a simple manner with the aid of the circulating pump that is present anyway. This simplifies the handling of the dishwasher by the user and in particular allows a minimization of fine filter cleaning to be carried out manually by the user.

According to a further feature of the invention, it is provided that the second suction line has a suction section that protrudes into the collecting pot. According to this embodiment, the intake line does not open out into the collection pot on the peripheral side, but rather an intake section in the form of a nozzle is provided, which protrudes into the collection pot. There is such a distance between the suction-side suction port of the suction pipe and the bottom of the collection pot. Thus, the suction portion provides a suction port that is above the bottom of the sump. The spacing has the advantage that, in the event of backwashing, particles detaching from the filter can accumulate at the bottom of the collection pot and are not sucked in via the second intake line and circulated in the backwashing circuit.

It is therefore also provided according to a further feature of the invention that the suction section provides a suction opening which is located above the connection point of a waste water pipe connected to the collection pot. It is thus advantageously permitted to detach particles adhering to the filter by backwashing, which particles then accumulate in the lower region of the collection pot, from where pumping out through the waste water pipe can then take place after backwashing has been completed. The particles that accumulate at the bottom of the collection pot as a result of backwashing can thus be discharged via the waste water pipe.

According to a further feature of the invention, it is provided that the circulating pump is connected directly to the second intake line. According to this embodiment, both the first and the second suction line are connected directly to the circulation pump. Depending on the direction of rotation of the circulating pump, washing liquor is sucked in either via the first suction line or the second suction line, with introduction into the circulating pump taking place directly. Accordingly, the circulating pump must have two connections for suction lines.

According to an alternative embodiment of the invention, it is provided that the circulating pump is connected to a supply line leading to a spray arm arranged in the washing compartment, with the second intake line opening into the supply line. Accordingly, the second intake line is not connected directly to the circulating pump, but indirectly with the interposition of a section of a supply line connected to the circulating pump.

A circulation pump is typically connected to a suction line as well as to a supply line. In the washing operation, washing liquid reaches the circulation pump via the suction line, from where the supply line is then charged. The supply line is in turn connected to at least one spray arm Spray device connected to the dishwasher. In normal operation, the washing liquor flows from the collection pot via the intake line into the circulation pump and from there via the supply line to the spray arm.

The second intake line provided according to the invention is now connected to the supply line. In backwash operation, washing liquor is sucked in from the collection pot via the second suction line, with the washing liquor conveyed via the second suction line flowing into the supply line connected to the suction line and from there to the circulating pump. The rinsing fluid sucked in in this way is discharged back into the collection pot via the line that serves as the first suction line during rinsing operation. Accordingly, in backflushing operation there is a circulation circuit via the second suction line, the supply line, the circulating pump and the first suction line, with the first suction line in backflushing operation not functioning as a suction line but as a discharge line.

In order to ensure that during normal operation no washing liquor introduced into the supply line flows via the second suction line into the collection pot, a blocking means, in particular a blocking valve, is provided which interacts with the second suction line. In normal rinsing operation, this blocking means or blocking valve and thus also the second intake line are blocked. The washing liquor conveyed in pump operation is therefore conveyed solely via the supply line to the spray arm connected to it. As soon as the circulating pump switches to backwash operation, the blocking means of the second intake line is opened so that washing liquor can be conveyed in the opposite conveying direction from the collection pot via the second intake line and the supply line connected thereto.

In particular, a water diverter can be provided as a blocking means, in particular the water diverter that is present anyway, which moreover serves to guide the washing liquor alternately, starting from the circulating pump, to the various spray arms. This water switch can be connected downstream of the circulating pump and/or integrated into the circulating pump or the circulating pump housing.

The connection of the second intake line to the supply line is preferred in contrast to a direct connection of the second supply line to the circulating pump, because the already existing line paths such as in particular already existing supply line can be used. Both the construction effort and the length of the cable routes are minimized in this way.

According to a further feature of the invention, it is provided that the second suction line is formed by a line section of a supply line which protrudes through the collection pot and is connected to a spray arm.

The spray device of a dishwasher typically has three spray arms. An upper, a middle and a lower spray arm are provided. The upper and the middle spray arm are supplied with rinsing water via a separate or a common supply line. The lower spray arm is connected to a separate supply line, which allows the lower spray arm to be operated independently of the other two spray arms. The supply line provided for the lower spray arm is routed through the collection pot, starting from the circulating pump or a water diverter connected to it. This structural design is particularly useful when both the collection pot and the lower spray arm are aligned centrally in relation to the bottom of the washing compartment. According to the invention, a section of this supply line leading to the lower spray arm can be used as a second suction line. This line thus serves as a feed line for the lower spray arm in flushing mode and as a suction line for the circulating pump in backwashing mode.

The supply line has a suction opening that opens and/or closes automatically depending on the flushing pressure. In particular, it is closed when the washing liquor is being conveyed in a first direction through the supply line, i.e. during rinsing operation, and is open when the washing liquor is being conveyed in the opposite direction, i.e. in backwashing operation .

For this purpose, the supply line is preferably designed in two parts, with the two line parts being arranged telescopically with respect to one another. Openings are formed in the line walls in the overlapping area of the line parts. These overlap when the two line parts are moved together. Such an overlap does not exist when the two line parts are in the extended state. This configuration causes the washing liquor pressure generated by the circulating pump in the washing operation to ensure that the two line parts are moved apart, so that the supply line lack of coverage of the Wall openings is tight, which can take place in the intended manner a promotion of washing liquor to the spray arm connected to the supply line. In the backwash operation, there is no pressure of the washing liquor that moves the two line parts apart, so that they move into one another following the force of gravity. In this position, the two wall openings overlap so that the suction opening required for backwashing is formed.

The invention also proposes a method for operating a dishwasher of the type described above, in which washing liquor is sucked in by means of the circulating pump via the first suction line during washing operation, in which for backwashing operation the direction of rotation of the circulating pump is reversed compared to washing operation, so that washing liquor is sucked in by the circulating pump via the second intake line.

Carrying out the method according to the invention makes it possible to distinguish between flushing operation on the one hand and backflushing operation on the other. In the backwash mode, washing liquor is conveyed via the second suction line to the circulation pump and from there back to the collection pot. As a result of the reversal of the conveying direction, particles, impurities and/or the like located on the inside of the fine filter are detached, which then accumulate in the lower area of the collection pot, from where they can be pumped out and discarded using the waste water pump. Carrying out the method according to the invention thus enables automated cleaning of the fine filter arranged in the collection pot, so that cleaning to be carried out manually by the user is preferably no longer necessary, but in contrast to the prior art it is at least to be carried out less frequently.

According to a further feature of the method according to the invention, it is provided that the second intake line is blocked during flushing operation. This ensures that during washing operation, washing water does not unintentionally flow past the spray arm that is actually to be pressurized in the bypass and back into the collection pot.

Fig. 1

in rein schematischer Seitendarstellung eine Geschirrspülmaschine der erfindungsgemäßen Art im Spülbetrieb;

Fig. 2

in rein schematischer Seitendarstellung eine Geschirrspülmaschine der erfindungsgemäßen Art im Rückspülbetrieb;

Fig. 3

ausschnittsweise die erfindungsgemäße Geschirrspülmaschine in schematischer Perspektivdarstellung;

Fig. 4

die Ausschnittsdarstellung nach Fig. 3, wobei der Spülbetrieb der Geschirrspülmaschine gezeigt ist;

Fig. 5

die Ausschnittsdarstellung nach Fig. 3, wobei der Rückspülbetrieb der Geschirrspülmaschine gezeigt ist;

Fig. 6

in schematischer Seitenansicht der Rückspülbetrieb der erfindungsgemäßen Geschirrspülmaschine;

Fig. 7

in einer Ausschnittsdarstellung eine zweite Ausführungsform, wobei der Spülbetrieb der Geschirrspülmaschine gezeigt ist,

Fig. 8

die Darstellung nach Fig. 7, wobei der Rückspülbetrieb der Geschirrspülmaschine gezeigt ist;

Fig. 9

in einer Ausschnittsdarstellung eine dritte Ausführungsform, wobei der Spülbetrieb der Geschirrspülmaschine gezeigt ist,

Fig. 10

die Darstellung nach Fig. 9, wobei der Rückspülbetrieb der Geschirrspülmaschine gezeigt ist; und

Fig.11

in rein schematischer Seitendarstellung eine Geschirrspülmaschine nach dem Stand der Technik.

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

1

in a purely schematic side view of a dishwasher type of the invention in the flushing operation;

2

a purely schematic side view of a dishwasher of the type according to the invention in backwash mode;

3

a detail of the dishwasher according to the invention in a schematic perspective view;

4

the cut-out view 3 12, wherein the washing operation of the dishwasher is shown;

figure 5

the cut-out view 3 12, showing the backwash operation of the dishwasher;

6

in a schematic side view of the backwash operation of the dishwasher according to the invention;

7

in a sectional representation of a second embodiment, wherein the washing operation of the dishwasher is shown,

8

the representation 7 12, showing the backwash operation of the dishwasher;

9

a sectional view of a third embodiment, showing the washing operation of the dishwasher,

10

the representation 9 12, showing the backwash operation of the dishwasher; and

Fig.11

a purely schematic side view of a dishwasher according to the prior art.

11 shows a dishwasher 1 according to the prior art in a purely schematic representation.

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. The washing compartment 3 has a loading opening 16 for loading the washing compartment with items to be washed.

In the intended use case, the items to be cleaned are treated with washing liquor, for which purpose the dishwasher 1 has a spray device 6 . In the exemplary embodiment shown, the spray device 6 includes an upper spray arm 7 and a lower spray arm 8.

The spray device 6 is fluidically connected by means of a supply line 11 to a circulating pump 9, by means of which the spray arms 7 and 8 of the spray device 6 are supplied with washing liquor in the case of a washing operation.

The rinsing container 3 providing the rinsing space 4 opens out with respect to the plane of the drawing 11 into a collection pot 5 on the underside. The circulating pump 9 is connected to this collection pot 5 by means of a suction line 10 . In terms of fluid technology, between the collection pot 5 and the washing chamber 4 there is an in 11 arranged not shown screening device.

The rinsing water circulated by the circulating pump 9 when used as intended reaches the collection pot 5 via the intake line 10, the circulating pump 9 and the supply line 11 in the direction of the arrow 14 to the spray arms 6 and 8 of the spray device 6. From here, the rinsing water is discharged in the direction of the arrows 18 is released onto the washware to be cleaned, from which it then drips and collects again in the collection pot 5 after passing through the sieve device.

Furthermore, a waste water line 13 together with a drain pump 12 is connected to the collection pot 5 . After completion of a washing operation that has been carried out as intended, the washing liquor that is no longer required in the collection pot 5 can be pumped out by means of the drain pump 12 in the direction of arrow 15 and transferred to a sewage system, not shown in detail.

The dishwasher 1 designed according to the invention is shown in a schematic side view in each of FIGS figures 1 and 2 shown. while showing 1 the so-called flushing operation and 2 the so-called backwash operation.

The circulation pump 9 according to the prior art is a radial pump. In contrast to this, the configuration according to the invention provides an axial pump as the circulating pump 9 . In addition, a second intake line 19 is provided, which fluidically connects the circulating pump 9 to the collection pot 5 . By means of a shut-off valve 20, the second intake line 19 can be blocked for the passage of washing liquor if necessary.

the inside 1 The flushing operation shown takes place in the manner known from the prior art. The washing liquor in the collection pot is sucked in via the first suction line 10 by means of the circulating pump 9 and then guided in the direction of the arrow 14 via the supply line 11 to the spray device 6 . The check valve 20 is locked during the washing operation, so that washing liquid sucked in via the suction line 10 cannot unintentionally enter the second suction line 19 .

2 shows the backwash operation. In contrast to a radial pump, the direction of rotation of the pump impeller can be reversed in an axial pump, with the effect that the direction of delivery of the pump is also reversed.

The direction of rotation of the pump impeller of the circulation pump 9 must be reversed for the backwash operation. In addition, the check valve 20 is to be opened. As a result, washing liquor is sucked in from the collection pot 5 via the second suction line 19, in the direction of arrow 21. The washing liquor conveyed in this way by the circulating pump 9 is conveyed back into the collection pot 5 via the suction line 10 in the direction of arrow 22 . In backwash operation, the spray device 6 is therefore not fed with washing liquor. In addition, in the backwash operation, the suction line 10 is not used as a line for sucking in washing liquor, but it is used as a line for returning the washing liquor sucked in via the second suction line 19 back into the collection pot 5 .

The possibility given by the construction according to the invention, from the flushing operation 1 into backwash mode 2 Being able to switch has the advantage that a sieve arranged in the collection pot 5 can be backwashed. Impurities, dirt particles and/or the like that have settled on the sieve as a result of normal rinsing operation can be loosened in the backwash operation and then pumped out by means of the waste water pump 12 and thus disposed of. The backwashing that is possible according to the construction according to the invention therefore allows automated cleaning of a sieve located in the collection pot 5, which means that manual sieve cleaning by the user is unnecessary.

The others Figures 3 to 10 show the embodiment according to the invention in detail.

3 shows the base 24 of the washing container 3. The base 24 is equipped with a recess 26, to which the collection pot 5 is connected. When used as intended, washing liquor located in the washing compartment 4 can flow into the collection pot 5 via the recess 26 .

A screening device is arranged between the washing chamber 4 and the collection pot 5 . In the exemplary embodiment shown, this screening device has a flat screen 25 inserted into the recess 26 and a filter unit 27 which in turn has a coarse screen 28 and a fine screen 29 .

In a manner known per se, the circulation pump 9 is fluidically connected to the collection pot 5 with the interposition of a first intake line 10 . On the output side, the supply line 11 is connected to the circulating pump 9 and leads to the spray arm 7 of the spray device 6 in the exemplary embodiment shown here.

According to the invention, a second intake line 19 is provided, which flows into the supply line 11 in terms of flow. The second supply line 19 is equipped with a check valve 20, which allows the second supply line 19 to be blocked selectively.

The second supply line 19 has an intake section 30 which, in the manner of a pipe socket, protrudes into the collection pot 5 . On the collection pot side, the suction section 30 provides a suction opening 31 which is located in the height direction above the connection point of the waste water line 13 which is also connected to the collection pot 5 .

4 indicates normal flushing operation. The washing liquor discharged from the spray arm 7 reaches the washing chamber 4, collects there and flows into the collecting pot 5 in accordance with the arrows 30. The washing liquor flowing into the collecting pot 5 in accordance with the arrows 30 can either flow through the flat filter 35 to the suction line 10 or pass through the coarse screen 28, followed by the fine screen 29 into the intake line 10. Under the effect of the pumping capacity of the circulating pump 9, the washing liquor reaches the supply line 11 via the suction line 10, through which the washing liquor is guided to the spray arm 7 in accordance with the arrows 14. The shut-off valve 20 is shut off during flushing operation, so that the flushing fluid pumped through the supply line 11 cannot get into the second intake line 19 .

figure 5 indicates the backwash operation. The direction of rotation of the pump impeller of the circulating pump 9 designed as an axial pump is reversed. In addition, the check valve 20 is opened. As a result, the rinsing water 20 in the collection pot is sucked in via the second intake line 19, passes through the open shut-off valve 20 and reaches the circulation pump 9 in accordance with arrow 21. From here, the rinsing water is returned to the collection pot 5 via the first intake line 10 in accordance with arrow 22 promoted. As can be seen from the illustration figure 5 based on the arrows 22, the flow through the fine sieve 29 of the filter unit 27 is in the opposite direction compared to the rinsing direction during rinsing operation, which leads to a detachment of the impurities, dirt particles and/or the like on the inside of the fine sieve 29. This factual connection results in particular from the presentation 6 .

As 6 can be seen, a filter cake 32 has accumulated on the inside of the fine sieve 29 as a result of a normal flushing operation. This filter cake 32 contains impurities, dirt and/or similar particles 34. According to the prior art, this filter cake 32, which forms during the flushing operation, has to be removed manually by the user by cleaning the fine sieve 29. The configuration according to the invention allows automated cleaning.

In the backwashing operation, the flow through the fine sieve 29 takes place in the opposite direction compared to the rinsing operation, namely in the direction of the arrows 22. As a result, the particles 34 forming the filter cake 32 detach and fall down in the collection pot 5, where they are in the lower area of the collection pot 5 accumulate like this in 6 can be seen. At the end of the backwashing operation, the drain pump 12 is to be switched on, with which the particles 34 that have collected in the lower area 33 of the collection pot 5 are then pumped away via the waste water line 13 .

As can be seen from the illustration 6 results, the second suction pipe 19 has a suction section 30 which protrudes into the collection pot 5 in the manner of a socket, whereby the suction opening 31 is in the vertical direction above the connection point of the waste water pipe 13 connected to the collection pot 5 . It is thus ensured that particles 34 that become detached during the backwash operation can accumulate in the lower region 33 of the collection pot and are not sucked in via the second intake line 19 and then circulated.

the figures 7 and 8th reveal another embodiment. while showing 7 the washing operation of the dishwasher and 8 shows the backwash operation of the dishwasher.

The embodiment according to figures 7 and 8th corresponds to the one after the figures 4 and 5 , but with the difference that the second intake line 19 is not connected to the supply line 11, but directly to the circulation pump 9. For this purpose, the circulating pump 9 is equipped with a corresponding water diverter, which releases the fluidic connection between the second intake line 19 and the circulating pump 9 in the backwash operation. In the rinsing operation, however, the fluidic connection between the second intake line 19 and the circulating pump 9 is blocked by the water diverter.

The second embodiment according to figures 7 and 8th has compared to the first embodiment according to figures 4 and 5 the advantage that a separate check valve 20 in the second intake line 19 can be dispensed with. The water diverter which is present in any case in the circulating pump 9 is used as the blocking means.

A third and preferred embodiment is in the figures 9 and 10 shown. while showing 9 the washing operation of the dishwasher and 10 shows the backwash operation of the dishwasher.

The special feature of the embodiment according to the figures 9 and 10 consists in the fact that the second intake line 19 serves to connect a lower spray arm 41 to the supply line 11 in terms of flow in the flushing operation. Like this 9 can be seen, is conveyed in the washing operation by the circulation pump 9 in accordance with the arrows 35 sucked washing liquor not only via the supply line 11 to the upper spray arm 7, but also via the second intake line 19 to a lower spray arm 41.

The second intake line 19 has a first section 36 and a second section 37 which are arranged telescopically relative to one another. The second section 37 can move translationally in the vertical direction 40 relative to the first section 36 . In the exemplary embodiment shown, a coupling element 38 is provided for connecting the second section 37 to the first section 36 , which coupling element provides through bores 39 .

In rinsing mode as shown in 9 is shown, the pump pressure caused by the circulating pump 9 ensures that the second, ie the upper section 37 of the intake line 19 moves upwards in the vertical direction 40 relative to the lower section 36 . In this upwardly moved position of the second section 37, the bores 39 are closed in a fluid-tight manner. The washing liquor circulated by the circulating pump 9 can therefore be conveyed to the lower spray arm 41 via the suction line 19 .

10 indicates the backwash operation. In the case of backwash operation, the second intake line 19 is not pressurized by the washing liquor conveyed by the circulating pump 9 . As a result, the second section 37 lowers downwards in the height direction 40 in relation to the first section 36 . As a result, the bores 39 are released, so that the washing liquor in the collection pot can be sucked in by the circulating pump 9 during backwash operation.

The opening or blocking of the bores 39 can be achieved in a structurally simple manner in that a screen element provided on the inside of the bores 39 opens or blocks the bores 39, depending on whether the two sections 36 and 37 of the second intake line 19 are in the vertical direction 40 moved up or down.

Reference sign

1

dishwasher

2

Housing

3

flush tank

4

dishwashing room

5

collection pot

6

spray device

7

spray arm

8th

spray arm

9

circulation pump

10

first intake line

11

supply line

12

drain pump

13

sewer line

14

Arrow

15

Arrow

16

loading opening

17

scullery door

18

Arrow

19

second intake line

20

check valve

21

Arrow

22

Arrow

24

floor

25

flat sieve

26

recess

27

filter unit

28

coarse screen

29

fine screen

30

intake section

31

intake port

32

filter cake

33

area

34

particles

35

Arrow

36

first section

37

second part

38

coupling element

39

drilling

40

height direction

41

lower spray arm

Claims (9)

1. Dishwasher, in particular a domestic dishwasher, comprising a washing container (3) that provides a washing chamber (4) and is intended to receive washware to be cleaned, a spray device (6) for applying washing solution to the washware to be cleaned, a collection pot (5) into which the washing container (3) fluidically opens, and a circulating pump (9), which is fluidically connected to the collecting pot (5) by means of a first suction line (10) and which can be operated in a first running direction, in which washing solution is suctioned from the collecting pot (5), via the first suction line (10), by means of the circulating pump (9) and flows from there via a supply line (11) to the spray device (6)

   and collects in the collection pot (5) after passing through a sieve device inserted in the collection pot (5), characterised in that

   the circulating pump (9) is an axial pump and that a second suction line (19) is provided, by means of which the circulating pump (9) is fluidically connected to the collection pot (5),

   the running direction of the circulating pump (9) being reversible,

   it being possible in the reversed second running direction of the circulating pump (9) for washing solution to be suctioned from the collecting pot (5), via the second suction line (19), by the circulating pump (9) and to be discharged back into the collecting pot (5) via the first suction line (10).
2. Dishwasher according to claim 1, characterised in that the second suction line (19) has a suction portion (30) which projects into the collection pot (5).
3. Dishwasher according to claim 2, characterised in that the suction portion (30) provides a suction opening (31) which lies above the connection point of a waste water line (13) connected to the collection pot (5).
4. Dishwasher according to any of the preceding claims, characterised in that the circulating pump (9) is directly connected to the second suction line (19).
5. Dishwasher according to any of the preceding claims 1 to 3, characterised in that the second suction line (19) opens into the supply line (11).
6. Dishwasher according to any of the preceding claims, characterised by a check valve (20) which interacts with the second suction line (19).
7. Dishwasher according to any of the preceding claims, characterised in that the second suction line (19) is formed by a line portion of a feed line which projects through the collection pot (5) and is connected to a spray arm (6, 7).
8. Method for operating a dishwasher according to any of the preceding claims, in which, in the washing operation, washing solution is suctioned by means of the circulation pump (9), via the first suction line (10), in which for a backflush operation the direction of rotation of the circulation pump is reversed by comparison with the washing operation, so that washing solution is suctioned by means of the circulating pump, via the second suction line (19).
9. Method according to claim 8, characterised in that the second suction line (19) is blocked during a flushing operation.

Images