EP2930261B1 - Method for operating a washing machine and washing machine - Google Patents

Description

Method of operating a washing machine and washing machine
The invention relates to a method for operating a washing machine with a tub for holding washing liquid for treating laundry, a rotatably mounted in the tub drum for receiving the laundry, a radiator and a Umfluteinrichtung for conveying washing liquid from a lower portion of the tub in a Upper area, based on the operating position of the washing machine. The method includes performing a wash program at a predetermined dial temperature. The washing program comprises a heating step and a subsequent washing step, wherein a washing liquid level is formed in the tub during the heating step so that the heating body is below the washing liquid level and the drum is above the washing liquid level based on the operating position of the washing machine and steam by operating the heating body is produced. The post-washing step is carried out after the heating step. During the post-washing step, the laundry is moved in the drum.

At the end of the heating step, warmed up scrubbing liquid is located in the lower portion of the tub, which is unused during the post-washing because it does not come into contact with the laundry in the drum. The heating of washing liquid that is not used for washing is not efficient.

The EP 2 348 151 A1 describes a method in which, in a post-heating step following the heating step, flooding only takes place when a desired temperature has been reached.

The invention thus faces the problem of providing a method of operating a washing machine and a washing machine which are more efficient.

According to the invention, this problem is solved by a method having the features of patent claim 1 and a washing machine having the features of patent claim 9. Advantageous embodiments and further developments of the invention will become apparent from the following subclaims.

In the method, the flooding device is activated during the subsequent washing step, depending on the selection temperature. The circulating device is activated, in particular, when it is efficient, the washing liquid heated in the lower region of the tub to promote in the upper region of the tub and thereby ensure a thorough mixing of the washing liquid with the laundry.

The achievable with the present invention consist in addition to improved efficiency is that when activated the Umfluteinrichtung a better mixing of washing liquid and laundry achieved and thereby the washing effect can be increased. On the other hand, if it is not efficient to activate the flooding device, the post-wash step is performed without activating the flooding device. The activation of the flooding device as a function of the selection temperature during the subsequent washing step therefore enables the process to be carried out in such a way that a good washing effect and energy balance can be achieved.

For the purposes of the present invention, the term "dialing temperature" means the temperature that a washing machine user sets by selecting a washing program to be performed. Washing programs are usually associated with a dial and laundry temperature, e.g. Easy to clean 30 ° C or coloreds 60 ° C. By selecting the dialing temperature, the washing machine user sets the laundry temperature at which he wishes to wash the laundry. The term "laundry temperature" refers to the temperature at which the laundry is washed in the post-wash step, i. the actual temperature measurable in the washing machine during the final washing. The dial temperature is in this sense the target temperature during the Nachwaschschritts, while the wash temperature represents the actual temperature during the Nachwaschschritts. The post-washing step is carried out according to the specifications of the set washing program, regardless of whether the circulating device is activated or not. During the Nachwaschschritts the laundry is moved by means of a rotating drum over a specified by the wash program Nachwasch period.

During the heating step, the washing liquid covers the radiator disposed in the tub, but is below the drum. That is, before the heating step washing liquid has been introduced into the tub, wherein it has moistened the laundry located in the drum. The laundry has taken up washing liquid, but there is no free liquor in the drum. During the heating step, the washing liquid is heated by means of the radiator to the predetermined by the washing program wash temperature. When the radiator is turned on, a temperature stratification sets in, which leads to microsolation occurring on the radiator surface after a period of time. Because of the short distance to the surface, the vapor bubbles manage to persist there, and they exit as vapor. Since energy can be transferred via the natural propagation behavior of the steam in principle into the wet laundry, the laundry is on the heated by the selection temperature predetermined wash temperature. After reaching the predetermined laundry temperature or a predetermined heating step for the heating step, the heating of the washing liquid is stopped. After the heating step, the post-washing step is carried out.

Depending on the selection temperature, washing liquid is conveyed from the lower region of the tub into the upper region of the tub. The lower portion of the tub is within the meaning of the present invention, the bottom of the washing machine. The sump is the lower part of the washing machine, in which the washing liquid introduced into the tub accumulates by gravity and is located below the drum. The upper portion of the tub in the context of the present invention, the area of the tub, which is located above the bottom. By means of the activation of the circulating device, the washing liquid located in the sump is conveyed into the upper region of the suds container and thus withdrawn from the sump.

According to the flooding device is activated during the Nachwaschschritts if the selection temperature is less than or equal to a limit temperature. The relation of the temperature of the washing liquid at the lower region of the tub to the selection temperature plays a particular role in the decision as to whether the activation of the circulating device makes sense or not. The limit temperature therefore depends on the theoretically expected or measured during the heating step temperature of the washing liquid located in the lower region of the tub.

The limit temperature is equal to the temperature of the washing liquid located in the lower region of the tub or preferably up to 5 ° C higher.

The limit temperature is selected in a temperature range which is between the temperature of the washing liquid located in the lower region of the tub and a temperature which is higher by 5 ° C. For example, the temperature of the washing liquid located in the lower region of the tub is about 45.degree. In washing programs with a selection temperature up to 45 ° C, it is then efficient to activate the Umfluteinrichtung because the funded by the Umfluteinrichtung fluid can on the one hand contribute to increase the laundry temperature and on the other hand ensures better mixing of laundry and washing liquid. If the selection temperature is equal to or up to 5 ° C higher than the temperature of the washing liquid located in the lower part of the tub, ie in the above example to 50 ° C, then probably the laundry temperature is not increased but rather slightly reduced, but an increase in the washing liquid in the laundry by activation of the flooding device can contribute to the improvement of the washing effect.

The limit temperature is preferably between 40 ° C and 60 ° C, more preferably between 45 ° C and 50 ° C. Depending on the washing machine type and, for example, the dimensions of the radiator and the dimensions of the lower region of the tub and the set selection temperature, the temperature of the washing liquid located in the lower region of the tub may vary at the end of the heating step. In a household washing machine, in which 1.0 to 2.0 liters or an average of about 1.5 liters of washing liquid are at the bottom of the tub at the end of the heating step, the temperature of the washing liquid located in the lower region of the tub is in the range of 35 to 55 ° C, more in the range of 40 to 45 ° C.

In a preferred embodiment, the flooding device is deactivated after activation as a function of the washing liquid level and / or time-dependent. If no washing liquid can be pumped out of the sump, the circulating device is preferably deactivated so that it does not become damaged. For this purpose, the method may include a time control of the circulating device and / or a control fluid level-dependent control for determining the time of deactivation of the circulating device. For example, the method may be deactivated after activation of the flooding device after a predetermined deactivation period. Alternatively, or in addition to the timing of the deactivation of the Umfluteinrichtung the Umfluteinrichtung can also be deactivated depending on the washing liquid level in the lower portion of the tub, which can be determined for example by means of sensor means.

Preferably, the flooding device is deactivated as a function of the washing liquid level when the amount of washing liquid to be conveyed by the flooding device is below a predetermined washing liquid quantity threshold value. Whether the amount of scrubbing liquid to be conveyed is below the predetermined scrubbing liquid amount threshold value depends on the level of scrubbing liquid in the lower area of the scrubber and can be determined, for example, by means of a sensor. The predetermined washing liquid quantity threshold value is preferably chosen such that the circulatory device is not damaged during the delivery due to an insufficient amount of washing liquid available to the washing liquid and / or its operation is ineffective.

In a preferred embodiment, after deactivation, the flooding device is reactivated when the wash liquid level in the lower portion of the tub is above a predetermined wash liquid level threshold. In this case the circulating device can be operated at intervals. Whether this makes sense can be determined for example by means of sensors which measure the washing temperature and the washing liquid temperature in the lower region of the tub. If the ratio of wash temperature and wash liquid temperature in the lower portion of the tub indicates that activation of the purge means contributes to the efficiency of the process, the purge means will be activated, otherwise not.

Preferably, the method is such that, in the case of activation of the flooding device, the flooding device at the beginning of the post-washing step, i. after the end of the heating step, is activated. As a result, the additional washing effect during the Nachwaschschritts be optimally utilized. The circulating device is deactivated during the Nachwaschschritts when the circulating device is no longer sufficient to be pumped washing liquid available and / or when a predetermined activation period has expired. In the case of an activation, the circulating device is preferably activated and deactivated once during the subsequent washing step, and the subsequent washing step is continued after the single-use operation of the circulating device. A one-time activation of the flooding device is sufficient in the case of a selection temperature suitable for activating the flooding device, in order to achieve an improved efficiency of the washing method in a simple manner.

In the case of a multiple activation and deactivation of the circulating device, although an improved mixing of laundry and washing liquid can be achieved, however, this is precluded by an increased procedural and constructional effort. The advantages and disadvantages of a single activation and deactivation of the circulating device are therefore to be weighed against a repeated activation and deactivation of the circulating device, in particular depending on the washing program selected by the washing machine user.

In a preferred embodiment, an amount of energy expended for operating the radiator during the heating step is adjusted such that the laundry temperature corresponds to the selection temperature. Upon selecting the dial temperature, the washing machine user sets the target temperature for washing the laundry in the post-washing step. The washing temperature, ie the actual temperature during the subsequent washing step, essentially depends on 3 input variables: 1. the selection temperature, 2. the amount of washing liquid and 3. the mixing temperature of washing liquid and laundry. The mixture of washing liquid and laundry results from the fact that the laundry absorbs the washing liquid introduced before the heating step. However, since the filled amount of washing liquid is adjusted so that no free liquor is present in the drum, the amount of washing liquid to be heated is in Bottom of the tub, so that it covers the radiator, but is below the drum. Selecting the selection temperature sets the temperature to be reached. Depending on the amount of washing liquid filled before the heating step and the mixing temperature of the laundry and the washing liquid, the amount of energy required during the heating step is adjusted such that the laundry temperature corresponds to the selection temperature.

The invention further relates to a washing machine with a tub for receiving washing liquid, a rotatably mounted in the tub drum for receiving laundry to be treated, a radiator, a Umfluteinrichtung and a control device for controlling a washing program. The control device is adapted to operate the washing machine during the implementation of the method described above. In order to provide an energy-efficient method, the control device is in particular configured to adjust the amount of washing liquid required for the selected wash program such that no free liquor is present in the drum, that the heating element generates steam during the heating step, and that the circulating device depends on the selection temperature is activated. Preferably, the control device is adapted to disable the Umfluteinrichtung in the case of activation time-dependent and / or washing liquid level dependent. Furthermore, the control device can preferably determine and adjust the amount of energy expended for operating the radiator.

Fig. 1

eine Waschmaschine in einer skizzierten Schnittdarstellung; und

Fig. 2

ein Waschprogramm als Diagramm im zeitlichen Ablauf.

Embodiments of the invention are shown purely schematically in the drawings and will be described in more detail below. It shows

Fig. 1

a washing machine in a sketched sectional view; and

Fig. 2

a washing program as a diagram in chronological order.

Fig. 1 shows a partial view of a washing machine in a sketched sectional view. Shown is the tub 3 a washing machine in which a drum 2 is rotatably mounted. In the drum 2 laundry 5 is filled for washing laundry. During a washing program, the drum 2 may be driven by a motor (not shown) to move the laundry 5 in the drum 2. The drum 2 is provided in the present embodiment of stainless steel and with a plurality of openings for flooding with washing liquid. In the lower region of the tub 3, a radiator 1 is arranged. The radiator 1 can heat in the tub 3 located washing liquid. The radiator 1 is installed in the washing machine in such a way that with an appropriate level of washing liquid, the active heating surface of the radiator 1 is directly below the washing liquid surface, so that in this case steam forms on the surface of the washing liquid, which flows through the drum in the laundry. moreover an inlet valve (not shown) is arranged in the upper area of the washing machine, which provides the washing machine with water from the supply network. The water is passed through a Einspülkasten (not shown) in the tub 3, wherein optionally located in the dispenser detergent is flushed into the tub 3. The tub 3 is connected to a drain device 6, which leads spent washing liquid from the tub 3 when activating a drain pump and usually opens into a sewer. In the lower region of the tub 3 a flooding device 4 is further arranged to promote washing liquid 7 from the lower region of the tub 3 in the upper region of the tub 3. The flooding device 4 has a circulating pump 4a, a circulating line 4b and an outlet 4c. The circulating pump 4a is connected on the inlet or suction side to the lower region of the tub 3, the so-called sump, and can, when the circulating device 4 is activated, wash liquid 7 located therein via the circulating line 4b and an outlet 4c such as a nozzle in the upper region promote the tub 3 and the drum 2 and spray on the laundry 5. A control device (not shown) of the washing machine controls the inlet valve, the activity of the drainage device 6, the activity of the flooding device 4, the motor and the radiator 1. The control device activates the flooding device 4 as a function of the selection temperature. Below a predetermined washing liquid level (not shown), there is the risk that the circulating pump 4 a can no longer completely aspirate washing liquid when the circulating device 4 is activated. In this case, the flooding device 4 is deactivated by means of the control device. Furthermore, the washing machine sensor means, for example, a sensor for detecting the washing liquid level or pressure in the tub 3 have.

Fig. 2 shows by way of example a timing of a washing program WP as a diagram, which in the in Fig. 1 Washing machine shown is carried out and to which reference is made herein. In the following description of the figure mentioned components refer to those in the Fig. 1 described components. On the time axis t, individual phases of the washing program WP are shown. The sequence of the washing program comprises a detection phase ER, a washing phase Wa, a rinsing phase Sp and a spin phase Sc. The washing machine user selects a dialing temperature by setting a washing program. The washing program starts. At the beginning of the washing program, in the detection phase ER, the type and amount of laundry in the tub or in the drum is detected. Subsequently, water is introduced through the inlet valve via the dispenser, whereby the stored in the dispenser detergent is introduced into the tub, so that the washing liquid is in the tub. The scrubbing liquid wets the laundry in the drum while it is being let into the tub while free liquor collects by gravity in the lower region of the tub and covers the arranged in the tub radiator, but is below the drum as a washing liquid. The laundry has therefore added washing liquid, but there is no free liquor in the drum. Then, the washing phase Wa starts. During a heating step Hz of the washing phase Wa, the washing liquid is heated by means of a radiator to the predetermined temperature of the washing program, which may be higher by any K than the selection temperature. When the radiator is turned on, a temperature stratification sets in, which leads to microsolation occurring on the radiator surface after a period of time. Because of the short distance to the surface, the vapor bubbles manage to persist there, and they exit as vapor. Since energy can be transmitted via the natural propagation behavior of the steam in principle into the wet laundry, the laundry is heated to the predetermined by the selection temperature wash temperature. After reaching the predetermined washing temperature or a predetermined time for the heating step, the heating of the washing liquid is stopped and a Nachwaschschritt Na follows. During the Nachwaschschritts Na, the laundry is moved by means of a rotating drum. Depending on the selection temperature, the circulating device is activated or not activated. In particular, the circulating device is activated during the subsequent washing step, if the highest possible process efficiency can be achieved with the washing liquid conveyed from the lower region of the liquor container into the upper region of the liquor container. The circulating device is activated in particular if the selection temperature is less than 45 ° C. In the case of activation, the circulating device is deactivated when a predetermined period of time has elapsed and / or when the washing liquid level in the lower region of the tub has dropped to a level such that the circulating pump can no longer completely draw in washing liquid. If the dialing temperature is more than 45 ° C, the post-washing step Na is carried out without activating the circulating device. The washing phase Wa is terminated by pumping out the washing liquid from the tub, wherein the drainage device is activated and the washing liquid is removed from the tub as far as possible. If necessary, the drum is operated at a high speed in order to remove the washing liquid present as a bound liquor from the textile fibers of the laundry as much as possible. Subsequently, fresh washing liquid, which consists essentially of water, is introduced into the tub. Then, a rinsing phase Sp starts, in which the drum moves the laundry in the washing liquid. Optionally, during the rinsing phase Sp, the flooding device can be activated. At the end of the rinsing phase Sp, the rinsing liquid is pumped off and removed via the drainage device. Subsequently, a spin phase Sc is performed, which is used to drain the laundry serves. In this case, the drum is rotated at a speed, so that the laundry is applied to the drum shell and the washing liquid is pulled out of the laundry through the openings of the drum due to the centrifugal force. The drain device is activated so that the washing liquid is removed from the tub.

LIST OF REFERENCE NUMBERS

HE

acquisition phase

Hz

heating step

N / A

post wash

sc

spinning phase

sp

rinsing phase

Wa

washing phase

1

radiator

2

drum

3

tub

4

Umfluteinrichtung

4a

Umflutpumpe

4b

Umflutleitung

4c

outlet

5

Laundry

6

off device

7

washing liquid

Claims (8)

1. Method for operating a washing machine comprising a suds container (3) for receiving washing liquid for treating laundry (5), a drum (2) which is rotatably mounted in the suds container (3) and intended for receiving the laundry (5), a heating member (1) and a recirculation device (4) for conveying washing liquid out of a lower region of the suds container (3) into an upper region, based on the operational installation position of the washing machine, the method comprising carrying out a washing programme which comprises a heating step and a post-washing step carried out after the heating step has been completed, a washing liquid level being formed in the suds container (3) during the heating step such that the heating member (1) is below the washing liquid level and the drum (2) is above the washing liquid level, based on the operational installation position of the washing machine, and steam being generated by operating the heating member (1), characterised in that the recirculation device (4) is activated during the post-washing step if the selection temperature of the washing programme is less than or equal to a limit temperature which is equal to or up to 5°C higher than the temperature of the washing liquid in the lower region of the suds container.
2. Method according to the preceding claim, characterised in that the limit temperature is between 40°C and 60°C, preferably between 45°C and 50°C.
3. Method according to either of the preceding claims, characterised in that, after activation, the recirculation device (4) is deactivated depending on the washing liquid level and/or time.
4. Method according to claim 3, characterised in that the recirculation device (4) is deactivated depending on the washing liquid level if the amount of washing liquid to be conveyed by the recirculation device is below a predetermined washing liquid amount threshold.
5. Method according to either claim 3 or claim 4, characterised in that, after deactivation, the recirculation device (4) is reactivated if the washing liquid level in the lower region of the suds container (3) is above a predetermined washing liquid level threshold and/or if a predetermined period of time has passed.
6. Method according to any of the preceding claims, characterised in that, when the recirculation device (4) is activated, the recirculation device (4) is activated at the beginning of the post-washing step.
7. Method according to any of the preceding claims, characterised in that an amount of energy to be expended in order to operate the heating member (1) is set during the heating step such that the laundry temperature corresponds to the selection temperature.
8. Washing machine comprising a suds container (3) for receiving washing liquid, a drum (2) which is rotatably mounted in the suds container (3) and intended for receiving laundry to be treated (5), a heating member (1), a recirculation device (4) and a control device for controlling and/or regulating a washing programme, characterised in that the control device is designed to operate the washing machine in accordance with a method according to any of claims 1 to 8 while carrying out the heating and post-washing steps.

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