EP2710947B1 - Water-bearing household device with a fill level detection device and leakage prevention unit combined in a single measuring device - Google Patents

Description

The invention relates to a water-conducting household appliance, in particular a dishwasher, which has at least one operating space leading liquid for cleaning rinse or laundry, wherein the processing space is assigned a detection unit for determining the level of the wet area, and wherein a safety unit below the wet area for Detection of unwanted fluid supply is provided.

In such water-conducting household appliances, for example, the filling of a rinsing or similar treatment chamber is often determined by impeller or similar detection units, which are arranged in the inlet, which is usually quite high up on the respective household appliance, to said wet area.

It is also known to provide below a wet area a float coupled to a microswitch or similar sensor as a safety unit from which an unwanted liquid intrusion, i. a leakage fluid from the wet area is detectable. In this case, by flooding into this area, which is below the wet area, a floating of the float causes, so that this can cause, for example, the microswitch.

The aforementioned detection and safety units are located apart from each other and each require its own wiring, so that the assembly and material costs are high and thus considerable costs.

The document DE 36 32 001 A1 shows a mechanically controllable valve for the water inlet in water-bearing household appliances, such as dishwashers. For this the only figure of the DE 36 32 001 A1 a solenoid valve consisting of a magnetic drive and a valve body with its water outlet. Between the valve body and the spout is the mechanically controllable valve in the water inlet looped, which consists essentially of a membrane with a pressure equalization bore and a plunger. The plunger closes and opens the pressure compensation hole depending on the position of a permanent magnet. The permanent magnet is part of a floating body, which is arranged in a housing. About an inlet opening of the container of the dishwasher is connected via a raised hose connection with the interior of the housing such that when a predetermined water level in the housing, the plunger is raised by the permanent magnet and the valve is closed.

In the document DE 36 25 243 A1 is a liquid-conducting, electrically operated device described in which a controllable shut-off valve is placed with a liquid container in a supply line. Under the liquid container and other water-bearing components of the device is a collecting tray for leak water. In the collecting trough a sensor is arranged, which controls the shut-off valve in the presence of leakage in the closed state. In order to achieve that a shut-off of the shut-off valve is achieved not only at a working level but also when exceeding a safety level with a simple protection system, the control device for evaluating the predetermined filling level comprises the sensor associated with the sump and a level detecting the working level. Furthermore, a liquid overflow is provided on the liquid container, which is associated with a lying above the working level safety level and opens into the drip tray, so that the sensor also works as Sicherheitsniveaufühler.

In the document DE 42 20 718 C2 a water-conducting household appliance is described, which has a container for liquid, which is filled via a disposed in a liquid supply electromagnetically controllable valve, and at least one arranged under this container container, each container influenced by the liquid level in the respective container level sensor, the a switch acted upon, is assigned. To reduce the effort is associated with simple means the containers arranged one another only a switch. The level sensors are designed as floats and the switch is operated independently of the floats.

The invention is based on the problem of achieving an improvement here.

The invention solves this problem by a water-conducting household appliance, in particular a dishwasher, with the features of claim 1. Accordingly, a water-conducting household appliance, in particular dishwasher, proposed, which has at least one leading in operation liquid processing space for cleaning rinse or laundry, wherein the processing space is associated with a detection unit for determining the respective actual level of the wet area, and wherein a security unit for detecting an unwanted fluid admission below the wet area is provided, wherein the detection unit and the security unit are combined to form a common measuring device. In this case, the measuring body of the detection unit is designed as a common structural unit with the measuring body of the safety unit.

With the invention, a water-conducting household appliance, such as a dishwasher, created, which makes it possible to detect during operation both a liquid filling a wet area and an unwanted liquid supply below at least one wet area or monitor, without requiring two different, each separately cabling measuring devices would have to be provided. The material and assembly costs are significantly reduced by the fact that the at least one detection unit and the at least one safety unit are combined to form a common measuring device. Thus, a water-conducting domestic appliance is provided with a filling detection device and leakage safety unit combined to form a common measuring device, which saves functional components compared with conventionally designed water-conducting domestic appliances.

According to one embodiment, the common measuring device comprises a common sensor unit. If advantageously the common measuring device comprises a common sensor unit, it is sufficient to interrogate this, only one sensor unit, in order to obtain both information about the level in the wet area, such as in the washing, as well as information about an unwanted liquid supply underneath. For this, the cabling is minimized. In particular, only one set of cables is required, which significantly reduces costs.

As a result of the fact that the actual level of the wet area, for example a washing compartment (in the case of a dishwasher), is determined directly, an indirect determination via, for example, an impeller counter is dispensable. In addition, events in the washing container of a dishwasher, such as overturning glasses or increased foaming, can also be detected.
Preferably, the common measuring device comprises a, in particular analog, displacement sensor, which can give a, preferably linear, signal dependence to the liquid level in the wet area and / or in the area below.

According to a further embodiment, the displacement sensor is set up in a double function to detect both a deflection of the detection unit for determining the actual level of the wet area and a deflection of the safety unit below the wet area.

If both a deflection of the detection unit for a liquid filling and a deflection of the safety unit below the wet area can be detected by the displacement sensor in a double function, the wiring complexity and the control effort for the signal detection and signal evaluation are minimized.

In this case, the detection unit for determining the actual level of the wet area preferably comprises a membrane with a measuring body extending downwardly therefrom with a component, which may, for example, have a pen-like outline shape and thereby form a light, long and narrow body.

Additionally or independently thereof, the safety unit may comprise a float having a measuring body extending upwardly therefrom with a component. In the case of leakage, ie when the at least one wet area, in particular the washing compartment of a dishwasher, loses liquid and drips down from the bottom area of the container of the domestic appliance, in particular the washing compartment, the upward movement of the float can be caused by the upward movement of the measuring body coupled to the float be properly detected by a detection unit such as a coil assembly in a simple manner.

To save material and simplify the design and installation of the measuring body of the detection unit is designed as a common unit with the measuring body of the safety unit. A single measuring body then suffices to fulfill both monitoring functions mentioned above.

With the said pin-like measuring body whose movement can be easily detected without contact, in particular, the pin can be moved in a coil interior, so that its movement is detected magneto-inductively.

In terms of manufacturing, it is favorable if the detection unit comprises a membrane arranged in a bottom section of the wet region and connected to the measuring body of the detection unit, so that the membrane movement can be converted into a movement, in particular vertical movement, of the measuring body.

In this case, for an inexpensive production, the measuring body may expediently be formed in one piece with the membrane.

In particular, the safety unit can comprise a float arranged below a bottom section of the wet area and connected to the measuring body of the securing unit, so that there a liquid admission would lead to an upward movement of the measuring body.

As stated above, the measuring body of the detection unit is designed as a common structural unit with the measuring body of the safety unit. The measuring body of the detection unit for determining the actual level of the wet area and the measuring body of the safety unit for detecting an unwanted liquid supply below the wet area act in an identical direction, in particular in the positive z-direction of the household appliance. The positive z-direction corresponds to an upward movement of the measuring body.

Both with a volume increase of the level of the wet area as well as with an increase in volume of the liquid below the wet area is the common Building unit of the detection unit and the safety unit trained measuring body moves in an identical direction.

Both a liquid supply in the wet area and a liquid supply below the wet area lead to an upward movement of the measuring body. Consequently, the evaluation of the detected sensor signal, for example a coil pair, through which the measuring body is guided, can be easily designed.

In accordance with a further embodiment, the detection unit comprises a membrane arranged in a bottom section of the wet area and connected to the measuring body of the detection unit, and a space sealed below the membrane and with a further membrane, which has a pressure port which leads to a pressure line arranged in the wet area the pressure in the positive z-direction can be coupled to the membrane. Through the further membrane of the measuring body is guided.

Through the space provided, the discharge nozzle and the pressure line connected to the pressure line, it is possible to redirect the pressure of the wet area such that it is guided from below to the membrane. By using the pressure hose is a high flexibility of the positioning of the detection unit and thus the common measuring device in the household appliance, in particular in the sump or sump of the household appliance, possible.

Consequently, the positioning of the measuring device in the floor area is made more flexible. In particular, the measuring device does not have to be arranged at the lowest point of the sump. As a result, space can be optimized depending on the design of the household appliance.

Other developments of the invention are given in the dependent claims.

The above-explained and / or reproduced in the subclaims advantageous embodiments and refinements of the invention can - in addition to z. B. in cases of clear dependencies or incompatible alternatives - individually or in any combination with each other.

• In den Figuren zeigen:

  Fig. 1

  ein beispielhaftes wasserführendes Haushaltsgerät, hier als Geschirrspülmaschine ausgebildet, in schematischer und teilweise aufgebrochener Seitenansicht, wobei ein Spülbehälter vorgesehen ist, der in seinem unteren Bereich einen sog. Pumpentopf als Vertiefung ausbildet und im Bodenbereich dieses Pumpentopfes eine Membran enthält, die mit einem Messkörper funktional verbunden ist;

  Fig. 2

  eine herausgezeichnete und beispielhafte Detaildarstellung eines Pumpentopfes (etwa entsprechend dem Detail II in Fig. 1), der in seinem Boden eine mit einem nach unten ragenden Messkörper verbundene Membran aufweist, wobei der Messkörper auch mit einem außerhalb des Spülbehälters liegenden Schwimmer verbunden ist; und

  Fig. 3

  eine zu Fig. 2 alternative Ausgestaltung der gemeinsamen Messeinrichtung.

The invention and its advantageous embodiments and further developments and their advantages will be explained in more detail with reference to exemplary embodiments illustrative drawings. They show, in each case in a schematic outline sketch:

• In the figures show:

  Fig. 1

  an exemplary water-conducting household appliance, here designed as a dishwasher, in a schematic and partially broken side view, wherein a rinsing container is provided which forms a so-called. Pump pot in its lower portion as a recess and in the bottom region of this pump pot contains a membrane which is functionally connected to a measuring body is;

  Fig. 2

  a detailed and exemplary detail of a sump (approximately corresponding to the detail II in Fig. 1 ) having in its bottom a membrane connected to a downwardly projecting measuring body, wherein the measuring body is also connected to a float located outside the washing container; and

  Fig. 3

  one too Fig. 2 alternative embodiment of the common measuring device.

In the figures, elements with the same function and mode of operation are each provided with the same reference numerals. In this case, only those components of a household appliance are provided with reference numerals and explained, which are required for the understanding of the invention.

In the Fig. 1 Dishwasher 1 shown schematically is a water-conducting household appliance and designed here as an example as a household dishwasher. It has as a wet area at least one liquid-tight washing container 2 for receiving ware to be processed, such as dishes, pots, cutlery, glasses, cooking utensils u. on.

The washing container 2 is in particular on its front side of a door 3 tightly closed. This door 3 is in Fig. 1 shown in the closed position and, for example, to a lower horizontal axis 3a, which in the embodiment perpendicular to the image plane of Fig. 1 runs, swung forward and down. Also, the door 3 may be attached to the washing container 2 or a bottom assembly below the washing container 2, if necessary be that another, deviating from pivoting about a horizontal axis opening movement of the door 3 is possible.

The rinse tank 2 can be acted upon by a fresh water inlet with fresh water FW, for which an inflow determination, such as an impeller, is dispensable. The fresh water FW may optionally be provided in its circulation with cleaning, drying and / or brightening agents. It can flow into a sump 5 in the region of the bottom 4. The sump 5 is a region of the bottom of the washing container 2, in which liquid collects because it is lower than the remaining areas of the bottom of the washing container 2. From there it passes through a circulating pump 6 again as a rinse S into circulation and can, for example via one or more sprayers 7, 8, here two rotatable spray arms in different levels of the interior of the washing compartment 2, again for loading in the Spülkörben 9, 10 halterbaren items to be used. It is expediently pumped out of the device 1 as wastewater AW at the end of the respective liquid-conducting partial rinse cycle, in particular at the end of the rinse cycle and / or drying cycle of a dishwashing program to be carried out.

The rinsing container 2 thus forms, by way of example, a wet area leading in operation liquid FW, S. As in particular in Fig. 2 becomes clear, at least a portion of the wet areas, namely here the rinse tank 2, a designated generally by 11 detection unit for determining a level or a liquid filling this wet area 2 is assigned and described in more detail below. In addition, a security unit, generally designated 12, for detecting an undesired application of liquid below at least one wet area 2 is also provided. The safety unit 12 is thus located under the bottom or bottom part 4 of the washing container 2.

Both functional units, namely the detection unit 11 and the safety unit 12, are combined to form a common measuring device 13.

In this case, the common measuring device 13 comprises a common sensor unit 14, which in turn has at least one pin-like, narrow, upstanding measuring body 15 and a coil assembly 16 encompassing it. By means of this coil arrangement 16, the movement of the measuring body 15 upwards or downwards (positive or negative height direction) is detected without contact, in particular magneto-inductively.

In particular, the common measuring device 13 here contains an analog displacement sensor 14, in which the deflection of the pin 15 is directly proportional to the amount of water located above it in the wet region 2. On the other hand, the measuring body 15 is also one with, i. connected below the bottom part 4 of the washing compartment 2 float 17, so that a floating of this float 17 upwards (positive height direction) would also be detected by this sensor unit 14.

This means that of the only one sensor unit 14 in a double function, both a deflection of the detection unit 13 for determining the level or a liquid filling the wet area 2 and a deflection of the safety unit 12 as a signal for an unwanted liquid intrusion below the wet area 2 can be detected.

In order to make this possible, a liquid-tight membrane 18 made of elastic or flexible material is attached to the sump 5 in its lowermost region, for example directly molded, provided that the sump 5 is made of plastic. Clipping or other connection of the membrane 18 to the sump 5 is possible. From the movable by water pressure membrane 18 of the movable, pin-like measuring body 15, which may be attached directly to the membrane 18 or molded, extends with a component downwards. The membrane 18 is inserted or inserted in a liquid-tight manner in particular into an opening or through opening of the inner wall of the pump pot 5 and forms a partial surface of the inner wall thereof. Preferably, it is provided in the region of the bottom 4, ie the lowest lying zone of the sump 5. When viewed in its undeflected state, it preferably covers the opening or the passage opening (viewed from the interior of the sump 5) largely flush with the edge of the inner wall of the sump 5 surrounding the aperture. As a result, a largely smooth, continuous inner wall surface of the pump pot 5 is provided, which makes it insensitive to the adhesion or settling of dirt particles.

For the simultaneous formation of the safety unit 12, the measuring body 15 is connected in its lower region to the float 17, which is made of styrofoam, for example, and extends from there with a component upwards. Thus, the measuring body 15 is also movable by the float 17. In the normal state, in which there is no water below the washing container 2, the float 17 rests on the surface of a base support or a base assembly 19 on which or the washing container 2 is placed from above.

Thus, the measuring body 15 of the detection unit 11 forms a common structural unit with the measuring body 15 of the safety unit 12. The sensor unit 14 operates as an analog switch and detects the vertical movement of the measuring body 15 as a function of the quantity of liquid located above it in the wet area 2, in particular in the sump 5. If fresh water FW and / or rinsing liquor is introduced into the rinsing tank 2, the membrane 18 with the measuring body 15 fastened to it deflects downwards and thus transmits via the sensor unit 14 a signal which is directly proportional to this amount of liquid. This is an actual value, so that water remaining in pots or glasses that are open at the top is not detected. If, however, a glass tilts and discharges its previously stored liquid into the washing container 2, this can be detected via the detection unit 11, so that the controller can respond very finely. Also, e.g. Foaming is detectable or detectable via this direct detection of the actual liquid level. Even minimal inflow water volumes FW (eg due to a slightly leaky aquastop inlet valve for fresh water) can be detected. This results in significantly reduced technical error rates.

Because the measuring body 15 is also connected as part of the safety unit 12 to the float 17 arranged underneath the bottom portion 4 of the wet area 2, its floating would lead to vertical lifting of the measuring body 15, so that an opposing signal is generated by the sensor unit 14 would and, for example, an emergency shutdown, or an immediate pumping in particular by a sewage pump (not shown in Fig. 1 ) could be used.

In particular, the unification or combination of the detection unit 11 and the safety unit 12 according to the invention results in a considerable amount in particular Cost savings by reducing the required components and by reducing the assembly effort and the assembly time. A big part of this has the reduction of the previously required two cable sets to only one set of cables.

The embodiment of the Fig. 3 is based on the embodiment of Fig. 2 and differs, however, in the embodiment of the detection unit 11 and thus the common measuring device 13th

In the embodiment of the Fig. 3 the measuring body 15 of the detection unit 11 is designed as a common structural unit with the measuring body 15 of the safety unit 12. With an increase in volume of the fill level of the wet area 2 and with an increase in volume of the liquid below the wet area 2, the measuring body 15 designed as a common structural unit of the detection unit 11 and the safety unit 12 is moved in the positive z-direction, ie, upwards.

For this purpose, the detection unit 11 has a sealed space 21 underneath the membrane 18. The sealed space 21 is sealed by a further membrane 20 for the passage of the measuring body 15 and comprises a pressure port 22. The pressure port 22 is connected to a pressure line 23 arranged in the wet area 2 Passing the pressure in the positive z-direction coupled to the membrane 18. In order for a liquid supply and thus an increase in pressure in the wet area 2 is guided to the membrane 18 so that it undergoes an increase in pressure from below. Thus, the membrane 18 is moved upward.

As a result of this upward movement of the membrane 18, the measuring body 15 connected to the membrane 18 moves upwards. This can be detected by the coil arrangement 16. In the same way, the membrane 18 is then moved upwards when the float 17 of the safety unit 12 buoys through liquid below the wet area 2. Thus, both the detection unit 11 and the safety unit 12 of the Fig. 3 at a respective increase in volume in an identical direction, namely upwards.

LIST OF REFERENCE NUMBERS

1

dishwasher

2

rinse tank

3

door

3a

swivel axis

4

Bottom of the washing container

5

swamp

6

circulating pump

7

spray arm

8th

spray arm

9

wash rack

10

wash rack

11

acquisition unit

12

security unit

13

measuring device

14

sensor unit

15

measuring body

16

coil assembly

17

swimmer

18

membrane

19

base support

20

membrane

21

room

22

pressure port

23

pressure line

FW

fresh water

AW

sewage

S

rinsing

Claims (14)

1. Water-bearing household device (1), in particular dishwasher, which has at least one processing chamber (2) bearing liquid (FW;S) in operation for cleaning items to be rinsed or washed, wherein a detection unit (11) for determining the respective actual fill level of the processing chamber (2) is associated with the processing chamber (2), and wherein a safety unit (12) for detecting an unwanted admission of liquid is provided underneath the processing chamber (2), wherein
   the detection unit (11) and the safety unit (12) are combined to form a single measuring unit (13), wherein a measuring body (15) of the detection unit (11) is formed as a single assembly with a measuring body (15) of the safety unit (12).
2. Household device (1) according to claim 1, characterised in that
   the single measuring device (13) comprises a single sensor unit (14).
3. Household device (1) according to one of claims 1 or 2, characterised in that
   the single measuring device (13) comprises a path sensor (14), in particular an analogue path sensor (14).
4. Household device (1) according to claim 3, characterised in that
   the path sensor (14) is arranged in a double function to provide both a displacement of the detection unit (11) to determine the actual fill level of the processing chamber (2) and also to detect a displacement of the safety unit (12) underneath the processing chamber (2).
5. Household device (1) according to one of the preceding claims, characterised in that
   the detection unit (11) comprises a membrane (18) having a movable measuring body (15) extending downwards out of said membrane (18) with a component.
6. Household device (1) according to one of the preceding claims, characterised in that
   the safety unit (12) comprises a float (17) having a measuring body (15) extending upwards out of said float (17) with a component.
7. Household device (1) according to one of the preceding claims, characterised in that
   the movement of the measuring body (15) can be detected contactlessly.
8. Household device (1) according to one of the preceding claims, characterised in that
   the movement of the measuring body (15) can be detected magnetoinductively.
9. Household device (1) according to one of the preceding claims, characterised in that
   the detection unit (11) comprises a membrane (18) arranged in a base section (4) of the processing chamber (2) and connected to the measuring body (15) of the detection unit (11).
10. Household device (1) according to one of the preceding claims, characterised in that
    the safety unit (12) comprises a float (17) arranged underneath a base section (4) of the processing chamber (2) and connected to the measuring body (15) of the safety unit (12).
11. Household device (1) according to one of the preceding claims, characterised in that
    the measuring body (15) has a pin-like, upright embodiment.
12. Household device (1) according to one of the preceding claims, characterised in that
    the measuring body (15) of the detection unit (11) for determining the actual fill level of the processing chamber (2) and the measuring body (15) of the safety unit (12) for detecting an unwanted admission of liquid act in an identical direction, in particular in a positive z direction, underneath the processing chamber (2).
13. Household device (1) according to claim 12, characterised in that
    the detection unit (11) comprises a membrane (18) arranged in a base section (4) of the processing chamber (2) and connected to the measuring body (15) of the detection unit (11), and a chamber (21) sealed underneath the membrane (18) with a further membrane (20), said chamber (21) having a pressure joint (22) which can be coupled to a pressure line (23) that can be arranged in the processing chamber (2) for guiding the pressure prevailing in the processing chamber (2) in the positive z-direction to the membrane (18).
14. Household device (1) according to claim 13, characterised in that
    the measuring body (15) is connected in the chamber (21) to the membrane (18) and is guided by the further membrane (20) into the chamber (21).

Images