EP2230985B1 - Water conducting household appliance - Google Patents

Description

The invention relates to a water-conducting household appliance according to the preamble of claim 1.

From the US 5,601,660 A For example, a dishwasher with a filter for filtering circulated water and a container for collecting material filtered out during operation is known.

Another dishwasher with a circulating device and a filter is for example from the US 3,949,578 A known. In this case, the filter is formed as a fine mesh, annular plastic strip and arranged in a pump chamber, the pump should allow an optional promotion of liquid in both directions.

In the US 2006/0219272 A1 For example, a dishwashing machine having a pump disposed in a sump is known which is intended to allow circulation of water in the sump, with both an inlet and an outlet of the pump being arranged in the sump.

The US Pat. No. 6,418,943 B1 discloses a dishwasher with a device for chopping coarse material.

The dishwasher of the US 3,129,711 has in a cavity below a water-collecting sump in the bottom of their washing a pump whose rotating impeller is externally surrounded by a fixed filter cylinder. During operation of the pump, water is forced through openings in the filter cylinder from the inside outwards into the outgoing volute (discharge nozzle) of the pump.

In the dishwasher of US 2,802,477 The impeller of a pump is also surrounded around by a cylindrical filter.

In order to prevent water in household appliances, such as dishwashers, that the conduit system is circulated in the wash liquor is polluted by dirt particles, a filter system is used, which may include a coarse filter, a fine sieve and a micro sieve. The coarse screen is used to retain dirt particles that can lead to a blockage of the drain pump. With a fine sieve, particles with a particle size greater than approx. 1 mm are retained and with a micro sieve particles with a particle size greater than approx. 0.15 mm are retained.

A water-conducting household appliance such. a dishwashing machine has a drain pump, with which at the end of a wash cycle soiled wash liquor can be conveyed out of the dishwasher into a house-side wastewater disposal system. Such lye pumps are designed so that they can promote larger particle sizes unhindered and there is no blockage of the drain pump. Therefore, lye pumps are arranged in such a way that polluted rinsing liquor is only roughly filtered during pumping.

Furthermore, a dishwasher has a circulation pump with which rinsing liquor can be circulated during a cleaning operation, ie, in the sump of a dishwasher collecting liquid is supplied by the circulation pump by a hydraulic system in the interior of the Spülbehälters arranged spray arms, with which a uniform loading of the dishes with Rinsing carried out. The spray arms have relatively small openings, so it is necessary to guide the circulated rinsing liquor through the fine and micro sieve, so that even the smallest particles are retained and the outlet openings of the spray arms can not clog. Accordingly, the circulation pump is designed with respect to the particle size tolerance.

The object of the invention is to provide a water-conducting domestic appliance, in particular a dishwasher or washing machine, whose filters have an increased reliability.

The object of the invention is solved by the features of claim 1. Advantageous developments of the invention are disclosed in the subclaims.

The invention is based on a water-conducting domestic appliance, in particular dishwashing or washing machine, with a hydraulic circuit in which rinsing liquid can be recirculated and in which at least one additional filter is provided for filtering circulated rinsing liquor. The solution according to the invention is characterized in that at least one additional filter for filtering circulated rinsing liquor is provided in the hydraulic circuit, which is arranged in a region of the hydraulic circuit in which recirculated rinsing fluid has a rotation. The rotation of the circulating rinsing liquor or its turbulent flow in this case causes the filter surface of the additional filter is not clogged by forming a filter cake, but an unhindered passage of rinsing liquid or rinsing liquor is guaranteed. This may be a complete rotation or only a partially circular or arcuate rotary or deflection movement, which is caused, for example, by deflecting means such as baffles or a channel guide.

For this purpose, according to the invention, a rotation of circulated rinsing liquor generating means is provided in the area of the hydraulic circuit. These may be stationary baffles or vanes that impart rotation to flowing rinse liquid. However, it is provided according to the invention that the means for generating a rotation of circulated rinsing agent comprise a circulating pump for circulating rinsing liquid.

According to the invention, it is provided that the additional filter is arranged in the circulation pump. Optionally, thus the usual way provided filter combination can be extended in the dishwasher to the additional filter. Alternatively, it is also possible to dispense with a filter arranged in the pump pot, as a result of which the pump pot can be made smaller and thus also the amount of dead water to be heated in the pump pot can advantageously be reduced.

The additional filter is preceded by the sieve combination arranged in the sump in the flow direction of the rinsing liquid, which can carry out at least one coarse and / or fine filtration. The rinsing liquid supplied to the additional filter is thus already precleared, so that the additional filter can be embodied as a microfilter, which is specially designed for filtering off dirt particles which are finely dispersed in the water.

According to the invention, the pump housing of the circulating pump has a paddle wheel space with a paddle wheel conveying the rinsing fluid and a pressure chamber arranged downstream thereof, into which the rinsing fluid delivered by the paddle wheel flows in a high flow rate. The pressure chamber can transition in the flow direction into a flow channel, which leads the rinsing liquid to an outlet-side discharge nozzle of the circulation pump. According to the additional filter is arranged in the pressure chamber, whereby the filter surface is constantly flushed due to the high turbulence of the inflowing into the pressure chamber rinsing liquid and thus can not be added by filter residues.

The pressure chamber according to the invention extends annularly around a central axis of the circulation pump. With a corresponding flow orientation, the rinsing liquid can move the pressure space in a rotational movement, i. H. tangential to a pressure chamber bounding the pump housing wall, flow through. The flow direction can be correspondingly designed by a according to the invention between the Schaufelradraum and the pressure chamber flow guide, such as a stator, according to the circumferential direction. Such a circular cross-flow in the pressure chamber ensures an increased residence time of the rinsing liquid in the pressure chamber and a complete overflow of the entire filter surface of the additional filter.

For a high filter performance, a complete flow through the circulating rinsing liquid through the additional filter is to be ensured. For this purpose, the flow-through pressure chamber from the additional filter according to the invention in an inlet chamber in which the rinsing liquid flows, and are divided into an outlet chamber from which the rinsing liquid flows to an outlet side discharge nozzle of the circulation pump. In terms of flow technology, it is favorable if the inlet chamber of the pressure chamber is located radially outside the outlet chamber of the pressure chamber with respect to the center axis of the circulation pump. The flushing liquid can thus flow over the additional filter in rotational movement along a radial outer wall of the pump housing.

To further increase the filter performance, it is advantageous if the additional filter has at least one, preferably disc-shaped filter means that on a hollow cylindrical filter medium carrier sits, which divides the pressure chamber in the aforementioned inlet and outlet chamber. For the largest possible filter surface, the filter medium provided on the filter medium carrier can protrude into the inlet chamber. However, the outer edge of the filter means is preferably not in contact with a radially opposite pump housing wall, but spaced therefrom by a flow gap in order to ensure the greatest possible flow around the filter medium.

Preferably, a number of filter media spaced filter media sit on the hollow cylindrical filter media carrier. The disc-shaped filter means therefore extend together with these filter spaces in an annular manner about the center axis of the circulation pump within the pressure chamber. In a guided in rotational movement through the pressure chamber liquid flow therefore takes place within these filter chambers, a large surface overflow of the filter surfaces, whereby the filter surfaces are constantly flushed and filter residues can not clog the filter surfaces. The cleaning of the additional filter, d. H. the cleaning of the additional filter upstream inlet chamber can be done by a flow reversal or a backwashing of rinsing liquid, whereby the filter residues are returned to the sump. Alternatively, the filter residues collecting on a side wall of the pressure chamber can be discharged into the pump pot via a separate, valve-controlled channel, from where they can be conducted into the sewage system by means of a drain pump. To support a removal of, the filter surfaces zusetzenenden filter residues can be provided in the above-mentioned filter spaces at least one freely movable cleaning body, which is freely movable in the filter chambers by the circular cross-flow of the rinsing liquid.

In a preferred embodiment, the pressure chamber of the circulation pump is assigned a heating element for heating the rinsing liquid. In the pressure chamber thus not only the additional filter is arranged but also in dual function beyond heats the rinsing liquid. In particular, due to the high turbulence of the high flow rate flowing into the pressure chamber rinsing liquid, the circulating in the hydraulic circuit rinsing liquid is heated accelerated in the pressure chamber.

Hereinafter, an embodiment of the invention with reference to the accompanying figures will be described.

Fig. 1

in einem schematischen Blockdiagramm eine erfindungsgemäße Geschirrspülmaschine; und

Fig. 2

in einer Seitenschnittdarstellung einen Hydraulikkreislauf der Geschirrspülmaschine verwendete Umwälzpumpe.

Show it:

Fig. 1

in a schematic block diagram of a dishwasher according to the invention; and

Fig. 2

in a side sectional view of a hydraulic circuit of the dishwasher used circulating pump.

In the Fig. 1 is a schematic diagram of a dishwasher with washing container 1, in which a not shown items to be washed in dish racks 3, 5 can be arranged. In the washing container 1 shown, two spraying arms 7, 9 provided in different spraying levels are arranged by way of example as spraying devices, with which the washware to be cleaned is supplied with washing liquid. Under the Spülbehälterboden a pump pot 11 is provided with associated circulating pump 13, which is fluidly connected via fluid lines 15, 16 with the spray arms 7, 9. The sump 11 is also connected via connecting pieces with a, connected to the water supply network fresh water supply line 17, and a drain line 18 in conjunction, in which a drain pump 19 is arranged to pump out contaminated rinsing liquid from the washing.

Like in the Fig. 1 indicated, the pump pot 11 is arranged on the upper side with a flat, funnel-shaped fine filter 21, in the center of a hollow cylindrical, cup-shaped coarse filter 22 is inserted. The fine filter 21 and the coarse filter 22 together with one according to the Fig. 2 used in the circulating pump 13 additional filter 23, a three-part filter system. In the filter system, a coarse and fine filtration by means of the fine and coarse filter 21 and 22, while a microfiltration takes place by means of the additional filter 23 described later.

The sump 11 is connected via a fluid line 24 with the downstream circulation pump 13 in connection. The liquid line 24 is, as in the Fig. 2 is indicated, pushed with its line end to an intake manifold 25 of the circulation pump 13, which is here for example coaxial with the central axis 26 of the circulating pump 13. The circulating pump 13 has a rotatable about the central axis 26 paddle wheel 27 which is provided in a Schaufelradraum 28 within a pump housing 29. The paddle wheel 27 is in drive connection via a drive shaft 30 with an only indicated electric motor 31.

The Schaufelradraum 28 is at its radially outer side via an annular gap 32 with an annular pressure chamber 33 in fluid communication. The pressure chamber 33 extends rotationally symmetrically about the central axis 26 and radially outwardly beyond the intake manifold 25 between the Schaufelradraum 28 and the pressure chamber 33 is provided in the annular gap 32 as a flow guide 34, which is non-rotatably mounted on a bearing seat 35 of the pump housing 26. The helically extending baffles of the stator 34 are made so steep that the inflowing rinsing liquid flows through the pressure chamber 33 in a high flow velocity in the radial circumferential direction, d. H. tangentially to the cylindrical pump housing wall 44. Accordingly, the rinsing fluid flow flowing into the pressure chamber 33 has a low velocity component in the axial direction. Downstream of the pressure chamber 33, an annular flow channel 36 connects, through which the rinsing liquid is conveyed tangentially through an outlet-side discharge port 37 into the liquid line 14.

As already mentioned above, the additional filter 23 is arranged in the pressure chamber 33. The additional filter 23 divides the pressure chamber 33 into a radially outer side inlet chamber 38 and into a radially inner side outlet chamber 39. The additional filter 23 has here, by way of example, three disk-shaped filter means 40, which sit on a hollow cylindrical filter medium carrier 41, which extends in the axial direction through the pressure chamber 33. The filter medium carrier 41 may be a pipe section whose front ends abut against opposite boundary walls 48 of the pressure chamber 33. The disk-shaped filter means 40 are spaced with their outer edges over a free flow gap 42 of a housing outer wall 44.

The disc-shaped filter means 40 project radially outwardly into the inlet chamber 38. In the axial direction, the filter means are spaced by annular filter chambers 43 in which, if necessary, cleaning bodies are provided which remove the filter residues from the filter surface.

Like from the Fig. 2 is further apparent, on the outside of the housing outer wall 44, an example here as Dickschichtheizelement 45 is provided which heats the circulating from the circulating pump 13 rinsing liquid.

During a circulation operation, the rinsing liquid is sucked in by the rotating bucket wheel 27 and guided at high flow speed through the bucket wheel space 28 into the pressure space 33. The arranged in the pressure chamber 33 filter means 40 are flowed through by appropriate flow orientation on the stator 34 in a circular cross-flow. Due to the transverse flow, residues are removed from the filter surface of the disk-shaped filter means 40 and forced outward by centrifugal action to the housing outer wall 44. The filter residues accumulate in the lower region of the housing outer wall 44.

The filter residues in the inlet chamber 38 of the pressure chamber 33 can be returned to the sump 11 by a backwash from the circulation pump 13. For this purpose, the paddle wheel 27 can be actuated in a direction opposite to the direction of rotation.

As an alternative to the backwashing, a valve-controlled drain 46 opening into the bottom region of the housing side wall 44 can be provided, as described in US Pat Fig. 1 is shown. Through the derivation 46 filter residues can be removed from the circulation pump. For this purpose, the discharge line 46 as a blocking element to a solenoid valve 47 which can be opened and closed by the control device 35. The derivative 46 is connected to the pump pot 11. The control device 35 can open the solenoid valve 47 simultaneously with the activation of the drain pump 19 in a cleaning operation. In this way, the filter residues collected in the pressure chamber 33 are conducted via the discharge line 46 and the pump pot 11 into the sewage system. <B> LIST OF REFERENCES </ b> 1 rinse tank 43 filters rooms 3, 5 baskets 45 heating element 7.9 spray arms 44 Housing outer wall 11 sump 46 drain line 13 circulating pump 47 blocking element 15 liquid line 48 boundary wall 16 liquid line 17 Fresh water supply 18 derivation 19 Drain pump 21 fine filter 22 coarse filter 23 additional filters 24 liquid line 25 intake 26 central axis 27 paddle wheel 28 Schaufelradraum 29 pump housing 32 annular gap 33 pressure chamber 34 stator 35 bearing seat 36 flow channel 37 pressure port 38 inlet chamber 39 outlet 40 filter means 41 Filter agent carrier 42 flow gap

Claims (11)

1. Water conducting household appliance, in particular a dishwasher or washing machine, having a hydraulic circuit, in which washing fluid can be circulated and in which at least one additional filter (23) is provided to filter circulated washing liquor, wherein at least one additional filter (23) for filtering circulated washing liquor is provided in the hydraulic circuit and is disposed in a region of the hydraulic circuit, in which circulated washing liquor is rotated, wherein means generating a rotation of circulated washing liquor are provided in the region of the hydraulic circuit, said means comprising a circulation pump (13) to circulate washing fluid, in which the additional filter (23) is disposed and which has an impeller chamber (28) with an impeller (27) that conveys the washing fluid and a pressure chamber (33) disposed downstream therefrom, wherein the additional filter (23) is disposed in the pressure chamber (33), wherein the additional filter (23) divides the pressure chamber (33) into an inlet chamber (38), into which the washing fluid flows, and an outlet chamber (39), from which the washing fluid flows to an outlet-side pressure connection (37) of the circulation pump (13) and wherein the pressure chamber (33) and/or the inlet chamber (38) and the outlet chamber (39) extend in an annular manner about the centre axis (26) of the circulation pump (13), characterised in that the inlet chamber (38) of the pressure chamber (33) is located radially outside the outlet chamber (39) of the pressure chamber (33) in relation to a centre axis (26) of the circulation pump (13), a flow routing element (34) is connected between the impeller chamber (28) and the pressure chamber (33) and the flow routing element (34) introduces the washing fluid tangentially along a pump housing wall (44).
2. Water conducting household appliance according to claim 1, characterised in that a pump sump (11) is connected upstream of the circulation pump (13) with a coarse and/or fine filter (21, 22) disposed therein.
3. Water conducting household appliance according to claim 2, characterised in that the coarse and/or fine filter (21, 22) has/have a bigger mesh width than the additional filter (23).
4. Water conducting household appliance according to one of claims 1 to 3, characterised in that the additional filter (23) has at least one, preferably disk-shaped filter means (40), which is positioned on a hollow cylindrical filter means support (41), which divides the pressure chamber (33) into the inlet and outlet chambers (38, 39).
5. Water conducting household appliance according to claim 4, characterised in that the hollow cylindrical filter means support (41) extends coaxially to the circulation pump centre axis (26) between opposing boundary walls (43) of the pressure chamber (33).
6. Water conducting household appliance according to claim 4 or 5, characterised in that the filter means (40) project into the inlet chamber (38) and at least one filter chamber (43) is bounded between the filter means (40) or housing walls, preferably extending in an annular manner about the centre axis (26) of the circulation pump (13).
7. Water conducting household appliance according to claim 4,5 or 6, characterised in that the filter means (40) is kept at a radial distance from a pump housing wall (44) in a radial direction outward by way of a flow gap (42).
8. Water conducting household appliance according to claim 6 or 7, characterised in that at least one preferably freely movable cleaning unit is disposed in the filter chamber (43).
9. Water conducting household appliance according to one of claims 1 to 8, characterised in that a heating element (44) for heating the washing fluid is assigned to the pressure chamber (33) of the circulation pump (13).
10. Water conducting household appliance according to one of the preceding claims 1 to 9, characterised in that the circulation pump (13) is connected to a pump sump (11) by way of a discharge line (46).
11. Water conducting household appliance according to claim 10, characterised in that a blocking element (47) is disposed in the discharge line (46), which preferably opens the discharge line (46) when a washing liquor pump (19) discharges washing fluid from the pump sump (11).

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