EP3508646B1 - Water supply control and washing machine - Google Patents

Description

The invention relates to a water supply control and a washing machine. In particular, the invention relates to a water supply control for wet washing with an automatic washing machine, which has a tub for holding water, a washing drum rotatably mounted in the tub for holding laundry, and a circulation system for conveying the water from a first area of the tub to a second area of the tub Having the tub and a sensor device for sensing a filling level of the water in the tub, and a corresponding washing machine.

In a washing method referred to as damp washing, with the moisture content of the laundry lying below the saturation moisture level, the water present in the washing process is essentially completely bound in the laundry. Due to a low fill level of the water in the tub that does not contact the washing drum, water introduced into the laundry is expelled by centrifugal centrifuges to achieve uniform moisture penetration and distribution of detergent and sprayed back into the laundry via a centrifugal circulation system.

In the water intake process for the washing method referred to as wet washing, water quantities therefore run in which are at a saturation state below the full saturation of the laundry, which is also referred to as drip saturation.

According to a prior art that is not documented in writing, it is common in the water intake process for wet washing that the amount of water let in in a water intake step results in a fill level in the tub that is above a lower edge of the washing drum. The laundry absorbs water until the fill level reaches the lower edge of the washing drum, with the washing drum preferably being reversed during this time. From this filling level, the laundry no longer touches the water and can therefore not absorb any water. If the reverse is continued, the time elapses unused and the water standing in a sump of the tub is not distributed in the laundry.

The document DE 10 2014 106275 A1 discloses a water supply controller according to the preamble of independent claim 1.

The invention therefore faces the problem of providing a water supply control and an automatic washing machine that have an improved washing effect. According to the invention, this problem is solved by a water supply control with the features of patent claim 1 and a washing machine with the features of Patent claim 8 solved. Advantageous refinements and developments of the invention result from the following dependent claims.

The advantages that can be achieved with the invention consist not only in an optimized distribution of the water intake quantity in the water intake process of wet washing, but also in a time saving. On the one hand, the water that is available is sucked up, so that items of laundry in an area close to the base of the drum are also soaked through. On the other hand, the circulation system supports the distribution of the water when the water level has dropped to the level of the lower edge of the washing drum, in that a so-called sump liquor, i.e. the lye in the sump from this point onwards, is fed directly into the laundry via the circulation system is sprayed.

The washing machine can be a pure washing machine or a combination device such as a washer-dryer. Information on position and direction relates to the operating position of the washing machine.

1. a) eine Wassersmenge bis zu einer vorbestimmten Füllhöhe in den Laugenbehälter oberhalb einer Unterkante der Waschtrommel bei ausgeschaltetem Umflutungssystem zugeführt wird; und
2. b) wenn die Sensoreinrichtung sensiert, dass der Wasserstand im Laugenbehälter von der vorbestimmten Füllhöhe auf eine Füllhöhe gleich oder unterhalb der Unterkante der Waschtrommel sinkt, das Umflutungssystem eingeschaltet wird.

According to the invention it is provided that

1. a) a quantity of water up to a predetermined filling level is fed into the tub above a lower edge of the washing drum with the circulation system switched off; and
2. b) when the sensor device senses that the water level in the tub drops from the predetermined filling level to a filling level equal to or below the lower edge of the washing drum, the flooding system is switched on.

This makes it possible to distribute water in the laundry by suction for as long as possible, so that laundry items lying further back are soaked. If it is no longer possible to absorb the water from the laundry because the water level has dropped to the level of the lower edge of the washing drum, the flooding system is activated. This allows the remaining water to be sprayed into a core of the laundry so that this area can also absorb water quickly. The water and detergent are evenly distributed throughout the batch of laundry more quickly, which leads to an improved washing effect, since the detergent can reach all the dirt faster and more evenly.

The filling level at the lower edge of the washing drum therefore represents a switch-on threshold value. That is, if the filling level of the water in the tub drops from the predetermined filling level to a filling level equal to or less than the switching-on threshold value, the flooding system is activated.

The term “water” is understood to mean water that can also contain detergents in addition to pure water. It can therefore also be a lye in particular. In a preferred embodiment, the fill level is sensed using a pressure sensor as a sensor device, which is positioned at a predetermined height in the tub. As a result, a change in pressure from a level above the lower edge of the washing drum to a level equal to or lower than the lower edge of the washing drum can be sensed. The flooding system is then controlled depending on the pressure.

Alternatively or additionally, the fill level is sensed using a temperature sensor as a sensor device, which is positioned at a predetermined height in the tub. In this embodiment, the flooding system is controlled as a function of temperature. The sensor device is preferably positioned in a sump of the tub. The sump is a lower area of the tub. The fill level in millimeters of water column is preferably determined using the sensor device positioned in the sump.

In a preferred embodiment, the flooding system is only switched off again after it has been switched on according to b) if a fill level of the water is sensed which is less than a predetermined switch-off threshold value. More preferably, the predetermined turn-off threshold is a level that is in the sump. The predetermined turn-off threshold is preferably in the range of 0 to 147 Pa (0 to 15 mmHg), more preferably in the range of 0 to 98 Pa (0 to 10 mmHg), still more preferably in the range of 0 to 49 Pa (0 to 5 mmHg). ).

The invention also relates to an automatic washing machine, which has a tub for holding water, a washing drum rotatably mounted in the tub for holding laundry and a circulation system for conveying the water from a first area of the tub to a second area of the tub, a sensor device for sensing a filling level of the water in the tub and a control device which is designed and set up to control a water supply control according to one or more of the embodiments described above. The statements made about the water supply control apply equally to the washing machine and vice versa.

The sensor device is preferably a pressure and/or temperature sensor. More preferably, the sensor device is arranged in the sump of the tub. For example, the pressure sensor can be an analog pressure sensor that determines a pressure that forms in an air trap.

The flooding system is preferably designed to convey water from a lower area of the tub into an upper area of the tub. That Flooding system preferably comprises a flooding pipe connected to the lower portion of the tub, wherein the flooding pipe is further connected to a flooding pump adapted to pump the water into a bypass line where it is pumped out at the top of the tub. For example, the water is sprayed into the upper area of the tub by means of a nozzle which is arranged at one end of the bypass line.

Fig. 1

eine skizzierte Teil-Darstellung eines Waschautomaten;

Fig. 2

eine vergrößerte Teil-Darstellung des in Fig. 1 gezeigten Waschautomaten; und

Fig. 3a und 3b

einen zeitlichen Verlauf einer Füllhöhe und eines Schaltungszustands im Umflutungssystem während einer Wasserzulaufperiode.

An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows schematically and not to scale

1

a sketched partial representation of a washing machine;

2

an enlarged partial representation of the in 1 washing machines shown; and

Figures 3a and 3b

a time course of a fill level and a circuit state in the flooding system during a water intake period.

1 shows a sketched partial representation of a washing machine. The washing machine has a tub 1 for holding water (not shown) and a washing drum 2 rotatably mounted in the tub 1 for holding laundry 6 . The tub 1 is coupled to a water inlet which has a dispenser box 7 and a hose 8 connecting the dispenser box 7 and the tub 1 . Furthermore, the tub 1 is coupled to a drain device 4 via which water can be removed from the tub 1 .

The drain device 4 has a drain pipe 41 which is connected to a drain pump 42 which is designed to pump water into the drain line 43 which usually opens into a sewer. Furthermore, a sensor device 5 is arranged in the lower area of the tub 1, based on the operational set-up position of the washing machine, the so-called sump 11, so that a level of water in the tub 1 can be determined.

The washing machine also has a circulation system 3 which is designed to convey water from a lower area of the tub 1 into an upper area of the tub 1 . The flooding system 3 has a flooding pipe 31 which is connected to the lower area of the tub 1 . The circulation pipe 31 is also connected to a circulation pump 32, which is designed to pump water into the circulation line 33, where it is sprayed into the laundry 6 in the upper area of the tub 1, for example by means of a nozzle (not shown). Furthermore, the automatic washing machine has a control device (not shown) which is designed and set up to control a water supply.

When the water is supplied, water is supplied to the tub 1 via the flushing-in dispenser 7 and the hose 8, as indicated by the in 1 shown arrow indicated.

2 shows an enlarged partial representation of the in 1 washing machine shown in section II. In the water intake process of wet washing, an amount of water is supplied to the tub 1 so that a predetermined fill level h ₂ is reached, which is above a lower edge of the washing drum 3 . The flooding system 3 is switched off. The laundry 6 absorbs water until the water drops from the predetermined fill level h ₂ to a fill level h ₁ , which is at the lower edge of the washing drum 3 . From this filling level h ₁ , the laundry 6 no longer touches any water and can therefore no longer absorb any.

The controller (not shown) is designed and set up to control the drainage system 3 depending on the pressure in such a way that water is absorbed by the laundry 6 by suction until the filling level h ₁ is reached and from this level the drainage system 3 is switched on so that the water is conveyed from the lower area of the tub 1 to the upper area (not shown) of the tub 1 so that the laundry 6 can absorb water. If the water level is below a predetermined switch-off threshold value, for example a level h ₃ +49 Pa (5 mm water column), the level h ₃ corresponding to a position of the sensor device 5 in the tub 1, the flooding system 3 is switched off.

Figures 3a and 3b show a time course of a fill level and a switching state in the flooding system during a water intake period of in 1 and 2 washing machines shown. First, water is supplied to the tub until the predetermined level h ₂ is reached. In this case, the flooding system is switched off, with the unit of the circuit status in the flooding system being chosen arbitrarily. The laundry in the washing drum sucks up the water until the water drops to the fill level h ₁ , so that one can also speak of a negative slope. Then the filling level of the water in the tub is so low that the laundry cannot absorb the water. When the water has dropped from the filling level h ₂ to the filling level h ₁ , the flooding system is switched on, so that the filling level of the water in the tub is reduced relatively quickly. As soon as a level of 49 Pa (5 mmWs) is sensed, the flooding system is switched off. The level of water in the tub rises to a level greater than 49 Pa (5 mmWc).

reference list

h1

lower edge of the washing drum

h2

predetermined level

h3

Height of the sensor device

1

tub

11

swamp

2

washing drum

3

flooding system

31

flood pipe

32

circulation pump

33

bypass line

4

drain device

41

drain pipe

42

drain pump

43

drain line

5

pressure sensor

6

Laundry

7

flushing box

8th

Hose

Claims (10)

1. Water supply control for wet washing with a washing machine which has a suds container (1) for holding water, a washing drum (2) for holding laundry (6), which drum is rotatably mounted in the suds container (1), and a flooding system (3) for conveying the water from a first region of the suds container (1) into a second region of the suds container (1), and a sensor device (5) for sensing a fill level of the water in the suds container (1),

   a) an amount of water up to a predetermined fill level being fed into the suds container (1) above a lower edge of the washing drum (2) when the flooding system (3) is switched off; characterised in that,

   b) when the sensor device (5) senses that the water level in the suds container (1) drops from the predetermined fill level to a fill level which is equal to or below the lower edge of the washing drum (2), the flooding system (3) is switched on.
2. Water supply control according to claim 1, characterised in that the fill level is sensed using a pressure sensor as the sensor device (5), which pressure sensor is positioned at a predetermined level in the suds container (1).
3. Water supply control according to either claim 1 or claim 2, characterised in that the fill level is sensed using a temperature sensor as the sensor device (5), which temperature sensor is positioned at a predetermined level in the suds container (1).
4. Water supply control according to any of the preceding claims, characterised in that the sensor device (5) is positioned in a sump (11) of the suds container (1).
5. Water supply control according to any of the preceding claims, characterised in that after being switched on according to b), the flooding system (3) is only switched off again when a fill level of the water is sensed which is lower than a predetermined threshold value.
6. Water supply control according to claim 4, characterised in that the predetermined threshold value is a fill level in the sump (11).
7. Water supply control according to either claim 5 or claim 6, characterised in that the predetermined threshold value is in the range of from 0 to 147 Pa (0 to 15 mmWc), more preferably in the range of from 0 to 98 Pa (0 to 10 mmWc), even more preferably in the range of from 0 to 49 Pa (0 to 5 mmWc).
8. Washing machine which has a suds container (1) for holding water, a washing drum (2) for holding laundry (6), which drum is rotatably mounted in the suds container (1), and a flooding system (3) for conveying the water from a first region of the suds container (1) into a second region of the suds container (1), a sensor device (5) for sensing a fill level of the water in the suds container (1) and a control device, characterised in that the control device is designed and configured to control a water supply control according to any of the preceding claims.
9. Washing machine according to claim 8, characterised in that the sensor device (5) is a pressure and/or temperature sensor.
10. Washing machine according to either claim 8 or claim 9, characterised in that the sensor device (5) is arranged in a sump (11) of the suds container (1).

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