Method for operating a washing machine and washing machine

Abstract

The present invention relates to a method for operating a washing machine (1), the washing machine (1) comprising a tub (2), a washing drum (4), a drum drive, a circulation pump (5) for conveying liquid located in the tub (2) onto textiles (6) located in the washing drum (4), at least one level sensor (8) for detecting information concerning the fill level of the tub (2) with liquid and a control device (9).

Description

[0001] The invention relates to a method for operating a washing machine according to claim 1. Furthermore, the present application relates to a washing machine for washing textiles according to claim 12.

[0002] The washing machine comprises a tub in which a washing drum is mounted so as to be rotatably driven. The washing machine also has a drum drive by means of which the washing drum can be driven so as to rotate about its axis of rotation. The washing machine further comprises a circulation pump by means of which liquid in the tub can be circulated into the tub, wherein the circulation pump is configured such that the liquid can be conveyed onto textiles located in the washing drum. For this purpose, the circulation pump can cooperate in particular with a liquid line by means of which the liquid conveyed by the circulation pump can be guided to an upper end of the washing drum, so that during operation of the circulation pump, the liquid, which is typically drawn near the bottom of the tub or at the bottom of the tub, can be directed from above onto the textiles located in the washing drum.The washing machine further comprises at least one fill level sensor. This sensor is suitable for detecting information regarding the liquid fill level of the tub. To process this information, the washing machine further comprises a control device that is connected to the fill level sensor in a data-transmitting manner, so that the detected information can be transmitted to the control device and processed by it.

[0003] DE 10 2016 212490 A1 discloses a laundry care appliance with a tub, a laundry drum, a controller, and a pumping device. The controller is designed to determine the laundry load in the laundry drum based on the detected duration of the pumping time.

[0004] It is already known in the art to determine the saturation level of the textiles in the washing drum. This is important for a water supply control system, which is intended to automatically control how much water is introduced into the tub for a particular wash cycle. To determine the saturation level of the textiles, it is first necessary to determine the volume flow that can be or is expelled from the textiles during a specific expulsion period.

[0005] To determine this volumetric flow, it is known to activate the circulation pump and simultaneously increase the speed of the washing drum until a previously defined pressure level is reached at a pressure sensor installed in the tub. This process usually requires the washing drum's expulsion speed to be raised to a very high level, which is associated with both high mechanical stress on the washing machine's components and high noise emissions. Increasing the expulsion speed to this high level is necessary to expel enough water from the textiles so that a pressure increase can be reliably measured at the pressure sensor. If water is to be expelled at a lower speed instead, the volumetric flow cannot always be reliably determined. This is especially true when the washing drum is loaded with relatively little laundry, for example 1 kg or 2 kg.

[0006] The present application is based on the object of being able to determine the volume flow of liquid expelled from the textiles more reliably.

[0007] The underlying object is achieved according to the invention by means of the method having the features of claim 1. Advantageous embodiments emerge from the associated subclaims.

[0008] The method according to the invention is carried out as follows: The washing drum is driven to rotate about its axis of rotation. This can be done, in particular, such that the washing drum has a constant base speed. Simultaneously, the circulation pump is operated so that liquid in the tub is pumped onto the textiles. This operating state is maintained until the tub fill level reaches a previously defined value. The fill level is monitored by the fill level sensor, which records the corresponding information.

[0009] Preferably, the information is continuously recorded by the fill level sensor. "Continuously" in this context means recording the information at a specific sampling frequency. The latter is advantageously at least 50 Hz, preferably at least 100 Hz.

[0010] Once the fill level in the tub has reached the defined value, the circulation pump is switched off. The defined value that leads to this break can be, for example, 0 mm water column. In this scenario, the circulation pump is therefore only switched off after all of the liquid in the tub has been pumped onto the textiles by the circulation pump, so that no liquid remains in the tub. It can be assumed that, due to the rotary drive of the washing drum, liquid will constantly escape from the textiles into the tub. However, this liquid is immediately circulated back onto the textiles by the circulation pump. Alternatively, it is also conceivable that the defined fill level value, after which the circulation pump is switched off, corresponds to the tub being filled with a certain volume of liquid that is different from zero.The washing drum is driven at its base speed until the circulation pump is switched off.

[0011] In the context of the present application, switching off the circulation pump "after reaching the defined value" can, on the one hand, mean an immediate shutdown at the moment the defined value is reached. On the other hand, it is conceivable that the circulation pump is only switched off after a certain grace period after reaching the defined value, for example, after a few seconds. Thus, it is conceivable that the fill level of the lye container reaches the defined value, for example, 0 mm water column, and the circulation pump is not switched off until, for example, five seconds after this point in time.

[0012] In any case, the washing drum continues to rotate, with the liquid expelled from the textiles gradually collecting in the tub because the circulation pump is no longer active. In order to increase the volume flow of the liquid expelled from the textiles (particularly when the washing drum is lightly loaded) and thus improve the measurability of the volume flow, the speed of the washing drum is increased from the base speed to a higher expulsion speed after the circulation pump has been switched off. The washing drum can therefore be driven at the expulsion speed, for example, for the duration of a defined expulsion period over which the volume flow is to be determined. For example, the base speed can be 400 rpm and the higher expulsion speed can be 500 rpm.

[0013] While the washing drum is being rotated in the manner described, information regarding the fill level of the suds container is recorded by the fill level sensor. This information is sent to the control device and processed by it. The volume flow of the expelled liquid is then determined. For this purpose, the information from the fill level sensor is processed; for example, a respective fill level of the suds container can correspond to a known volume of expelled liquid. The relationship between the fill level and the volume of expelled liquid that is in the suds container when the fill level is present is given by the geometry of the suds container. Since this geometry is known, the volume of expelled liquid can be directly derived from a respectively recorded fill level.It is conceivable that the volume of expelled liquid can be represented as a function of the fill level of the suds container with liquid. Furthermore, it is conceivable that the volume of liquid present in the suds container is known for at least one defined fill level, which is detected by means of at least one fill level sensor. Preferably, the information that a certain volume of liquid is present in the suds container at a defined fill level is known for several different fill levels, wherein the different fill levels can be or are detected by means of different fill level sensors or by means of a single fill level sensor. The volume of expelled liquid corresponds to the difference between the volumes of liquid present in the suds container that existed at the two fill levels.

[0014] With the known volume of expelled liquid, the volume flow rate must be divided by the expulsion period over which the volume was expelled from the textiles to determine the volume flow rate. The result describes the volume flow rate, for example, in liters per minute [I / m], that was expelled from the textiles on average during the expulsion period.

[0015] The method according to the invention has many advantages. In particular, it is not necessary, as in the prior art, to increase the speed of the washing drum to a very high level for an extended period of time (in the prior art, over 1000 rpm are regularly required). Instead, the volume flow of the expelled liquid can generally be determined using a much lower base speed of the washing drum, for example, 350 rpm. The invention also provides for the case where only a comparatively small volume flow escapes from the textiles at the base speed. This can be the case in particular if the washing drum is filled with only a small amount of textiles, for example, 1 kg or 2 kg. In this case, as described, the speed of the washing drum is increased - preferably temporarily - to the expulsion speed, so that the volume flow is increased.The correlation here is that the higher the washing drum speed, the more liquid escapes from the textiles, i.e., the larger the volume flow. The expulsion speed is preferably still significantly below the values ​​​​typical in the state of the art, so that the mechanical stress on the washing machine components is reduced, as is the noise emissions from the washing machine during the process. If necessary, the expulsion speed can easily be well above 1000 rpm, for example, at 1600 rpm.

[0016] In a particularly preferred embodiment, the expulsion period extends between two points in time at which the volume of liquid with which the suds container was filled is known. In this case, a first point in time can in particular be the point in time at which the circulation pump is switched off, at which point in time, according to the above explanation, the fill level of the suds container can be, for example, 0 mm water column. The second point in time can in particular be a point in time at which a specific fill level of the suds container, different from zero, is detected by means of the at least one fill level sensor. In this embodiment, the volume that was expelled from the textiles during the expulsion period corresponds to the volume that results from the fill level detected by the fill level sensor at the second point in time.

[0017] The duration of the expulsion period advantageously corresponds to the time difference between the two specified times. This means that all values ​​for the above-described division of the volume by the duration of the expulsion period are known, allowing the average volume flow of the expelled liquid to be determined.

[0018] According to the above explanation, it is advantageous if the points in time that define the beginning and end of the expulsion period are those at which the liquid level of the lye container has reached a previously defined value. This procedure has the advantage that the volume of expelled liquid can be determined particularly easily at known fill levels, since the fill levels, whose values ​​are determined, can be linked to the volumes of liquid in the lye container. This can be achieved, in particular, by pre-filling the lye container with liquid up to a specific fill level, after which the volume of liquid admitted into the lye container is measured ("calibration"). This can, of course, also be determined digitally using appropriate design models.

[0019] Accordingly, it can be particularly advantageous if the volume of liquid expelled over the duration of the expulsion period is determined based on fill levels that existed at the times between which the expulsion period extends. The fill levels each correspond to a filling of the lye container with a specific volume of liquid. The resulting advantages have already been explained above.

[0020] It is also conceivable that the fill levels, which define the expulsion period, are not determined in advance, but rather the expulsion period itself, i.e. the two points in time that define the start and end of the expulsion period. At these defined points in time, the fill level of the lye container with liquid is determined using at least one fill level sensor, whereby the fill levels each correspond to a volume of liquid that was in the lye container at the respective times. The volume of liquid expelled during the expulsion period is calculated from the difference between the volumes of the liquid at the start and end of the expulsion period. The duration of the expulsion period is also known (time difference between the start and end of the expulsion period), so that all values ​​for determining the average volume flow are available.

[0021] Preferably, both the beginning and end of the expulsion period are selected such that the washing drum is rotated at the expulsion speed throughout the entire expulsion period. This ensures that the volume flow of the liquid escaping from the textiles is as large as possible and can be measured accordingly.

[0022] In a particularly advantageous embodiment of the method, the method comprises a preparation phase, which, in the structure of claim 1, is carried out chronologically before the first-mentioned method step a). The method steps mentioned in claim 1 can be regarded, within the meaning of the present application, as belonging to a measuring phase of the method, wherein - if present - the preparation phase is carried out chronologically before the measuring phase.

[0023] During the preparation phase, the washing drum speed can be increased to the base speed before the circulation pump is switched on. Starting from a starting value, for example, 300 rpm, the washing drum is gradually accelerated. Due to the deactivated circulation pump, liquid is expelled from the fabrics and collected in the tub.

[0024] Preferably, the speed is increased until a previously defined value for the fill level of the tub is detected by the fill level sensor. Once this value is reached, the speed of the washing drum is no longer increased. The speed then reached forms the "base speed" of the process. The circulation pump is then activated, allowing the measuring phase of the process to begin.

[0025] Furthermore, it can be particularly advantageous to determine the mass of all textiles in the washing drum. This can be done, in particular, using a mass inertia method, with the mass of the textiles preferably being determined while they are in a dry state. The parameter of the mass of the textiles, preferably in a dry state, can also be used as an input parameter for further evaluations.

[0026] If the mass is determined, it can be particularly advantageous if the control device automatically selects the ejection speed based on the mass of all the textiles in the washing drum. As already indicated, the method is particularly useful when only a small mass of textiles is present in the washing drum. The extent to which the washing drum speed should be increased from the base speed, i.e., the amount by which the ejection speed should be set, is preferably determined by the mass of textiles present. The rule here is that the lower the mass, the higher the ejection speed.By measuring the mass of the textiles, the automatic selection of the ejection speed, for example according to a previously defined function between the mass of textiles and the ejection speed, is particularly useful so that the washing machine can be operated optimally regardless of the user.

[0027] It can also be particularly advantageous to measure the amount of liquid introduced into the tub, preferably using an inlet sensor. Such a sensor can be formed, for example, by an impeller meter, which measures the volume of liquid introduced into the tub. This makes it possible to determine the total amount of liquid in the tub while the process is being carried out.

[0028] If the amount of liquid introduced into the tub is determined, it can be particularly advantageous if the expulsion speed is automatically selected by the control device depending on the amount of liquid. This procedure follows the consideration that if the total amount of liquid introduced into the tub is small, the volume flow of liquid expelled from the textiles will presumably also be small and correspondingly more difficult to measure. The extent to which the speed of the washing drum should be increased from the base speed, i.e. the amount by which the expulsion speed should be, is therefore preferably made dependent on the amount of liquid present. The rule here is that the smaller the amount, the higher the expulsion speed.By measuring the amount of liquid, the automatic selection of the ejection speed, for example according to a previously defined function between the amount of liquid and the ejection speed, is particularly useful so that the washing machine can be operated optimally regardless of the user.

[0029] If both the mass of the textiles and the amount of liquid introduced are determined, it is particularly advantageous if the expulsion speed is automatically determined by the control device depending on both the amount of liquid introduced into the tub and the mass of all textiles in the washing drum. This automatically determines the expulsion speed for each individual case, allowing the average volume flow to be determined with particular reliability. The function of the expulsion speed as a function of the mass of the textiles and the amount of liquid can be determined in advance based on empirical studies.

[0030] The underlying problem is further solved by means of a washing machine having the features of claim 12. Advantageous embodiments emerge from the associated subclaims.

[0031] The control device of the washing machine according to the invention is provided and configured to operate the drum drive and the circulation pump depending on the information detected by the fill level sensor such that the method steps of the method according to the invention are carried out. The washing machine is therefore particularly well suited to carrying out the method according to the invention. The resulting advantages have already been explained above. In particular, a volume flow of liquid expelled from the textiles in the washing drum over the duration of an expulsion period can be determined particularly reliably, even when the mass of textiles in the washing drum is comparatively low.

[0032] The washing machine is particularly advantageous if it has at least one inlet sensor for detecting information regarding the amount of liquid introduced into the tub. The inlet sensor can, in particular, be designed to determine the volume of all liquid introduced into the tub. For this purpose, the inlet sensor can be formed, for example, by an impeller meter.

[0033] Furthermore, such a washing machine can be advantageous in which at least one fill level sensor is formed by a pressure sensor or a contact sensor. In particular, if the fill level sensor is designed as a pressure sensor, it can preferably be assigned to a base of the tub, i.e. act in particular in the base of the tub. In this way, a hydraulic pressure of liquid in the tub can be determined using the fill level sensor, whereby a conclusion can be drawn about the fill level of the tub, measured from the base. Accordingly, the fill level of the tub can be determined particularly well using such a fill level sensor. With knowledge of the geometry of the tub, the volume of liquid in the tub can also be determined based on this information.

[0034] If the fill level sensor is formed by a contact sensor, it is advantageous if it is arranged at a vertically measured distance from the bottom of the lye container. With this configuration, the information from the fill level sensor can be interpreted to mean that at the moment the fill level sensor comes into contact with liquid, the lye container is filled with a specific volume of liquid, which corresponds to a fill level of the lye container with liquid corresponding to the distance of the fill level sensor from the bottom of the lye container. Knowing the geometry of the lye container, the volume of liquid in the lye container is thus known.

[0035] Furthermore, it can be particularly advantageous if the washing machine comprises a plurality of fill level sensors arranged at different distances from the bottom of the tub. In this way, at different times during the expulsion of liquid from the textiles in the washing drum, the volumes of liquid that were in the tub at these times can be determined. In this embodiment, the times can be defined in particular by the fact that the fill level sensors each came into contact with the liquid for the first time. From this, it can be concluded that the tub is or was filled at these times with a volume of liquid that corresponds to a fill level of the tub that corresponds to the distance of the respective fill level sensor from the bottom of the tub.The times at which the fill level sensors come into contact with the liquid are particularly well suited to defining the beginning and end of the expulsion period, while the volumes corresponding to the detected fill levels are particularly well suited to determining the volume expelled from the textiles during the expulsion period. In this embodiment, the fill level sensors are preferably contact sensors.

[0036] An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows: Figure 1A schematic representation of a washing machine according to the invention, Figure 2A speed curve of a washing drum during operation of the washing machine according to Figure 1 .

[0037] An example of implementation that is shown in the Figures 1 and 2illustrated, comprises a washing machine 1 which has a tub 2 and one inside the tub 2 rotating washing drum 4 The washing drum 4 is around an axis of rotation 3 mounted for rotation, whereby the washing drum 4 is rotatably driven by a drum drive not shown in the figure. In the washing drum 4 are textiles 6 stored, which can be washed by means of the washing machine 1 should be washed.

[0038] Furthermore, the washing machine includes 1 a circulation pump 5, which is intended and equipped to be placed in the lye container 2 liquid in the washing drum 4 textiles 6 To do this, the circulation pump 5 with a liquid line 7together, which directs the circulated liquid to an upper end of the washing drum 4 so that the circulated liquid flows from above onto the textiles 6 can fall. At one of the circulation pump 5 opposite end of the liquid line 7 For this purpose, a nozzle (not shown in the figure) can be arranged. The suction of the liquid from the tub 2 using the circulation pump 5 takes place in the area of ​​the floor 13 of the lye container 2, so that the circulation pump 5 all in the lye container 2 liquid from the lye container 2 can be seen.

[0039] Furthermore, the washing machine includes 1 a supply line 14, by means of the liquid from a liquid supply not shown in the figure into the tub 2can be introduced, whereby to convey the liquid into the tub 2 in the example shown a pump 15 is provided. In the supply line 14 In the example shown, an inlet sensor 10 which is formed here by a vane wheel meter. The inlet sensor 10 is therefore suitable for storing information concerning a volume of 2 introduced liquid.

[0040] Furthermore, the washing machine includes 1 a level sensor 8. This is the ground 13 of the lye container 2 assigned. The level sensor 8is formed here by a pressure sensor designed and configured to continuously detect information regarding a hydraulic pressure applied to a sensor surface, which acts on the pressure sensor in the form of a water column. The detected hydraulic pressure directly determines the height of the liquid level within the tub. 2, at which the liquid is located at any given time. In other words, the filling level of the lye container 2.

[0041] This information becomes a control device 9 of the washing machine 1 so that the control device 9 which is measured by the level sensor 8 information collected to ensure the operation of the washing machine 1 to control. The control device 9In the example shown, it is also connected to the inlet sensor in a data-transmitting manner 10 connected so that the inlet sensor 10 recorded information to the control device 9 conductive and can also be processed by means of them.

[0042] When carrying out the method according to the invention, before introducing liquid into the lye container 2 using an inertia method a mass of all textiles 6 which, when dry, can be stored in the washing drum 4 In the example shown, the washing drum is loaded with 2.0 kg of laundry. The pump then 15 Liquid through the supply line 14 into the lye container 2 The inlet sensor is used to 10 the total volume of liquid introduced is recorded. Furthermore, the washing drum 4around its axis of rotation 3 driven by the drum drive and at the same time the circulation pump 5 operated to inject the liquid into the textiles 6 Then, in a preparatory stage of the process, the circulation pump 5 initially deactivated, so that as a result of a further rotation drive of the washing drum 4 Liquid from the textiles 6 is expelled and in the lye container 2 To determine a base speed 11 for the washing drum 4 the speed of the washing drum 4 successively increased, for example with an acceleration of 20 rpm per second. This is Figure 2 particularly good using a speed curve 16 recognizable, which in a coordinate system the x-axis 17 time in seconds with on its y-axis 18worn revolutions of the washing drum 4 per minute. Using the level sensor 8 The filling level of the lye container is continuously 2 As soon as the fill level reaches a pre-set value, the speed of the washing drum 4 The achieved speed level will henceforth form the base speed 11. The circulation pump is then 5 reactivated, completing the preparatory phase of the procedure.

[0043] This is followed by a measuring section of the process. In this measuring section, the washing drum 4 initially continue with its previously determined base speed 11 rotationally driven. By means of the circulation pump 5 the solution in the tub 2 liquid via the liquid line 7 on the washing drum4 textiles 6 In the example shown, this process is maintained until the level sensor 8 It is detected that the filling level of the tub is 20 mm water column. In other words, at this point in time, all the liquid in the tub is 2 is located in the textiles 6 After a waiting time of five seconds, the circulation pump is then 5 deactivated while the washing drum 4 continue with the base speed 11 The speed of the washing drum is then 4 starting from the base speed 11 to a previously defined ejection speed 12 accelerated.

[0044] Due to the continuous rotation of the washing drum 4 with the increased ejection speed 12 liquid is released from the textiles6 expelled, which then settle in the lye container 2 The volume flow of the expelled liquid is due to the comparatively high expulsion speed of 400 rpm of such a magnitude that a change in the fill level by means of the fill level sensor 8 is easy to detect. Since the fill level of the lye container 2 is continuously recorded, here at a frequency of 200 Hz, information is available regarding a change in the fill level over time. At a defined time after the circulation pump is switched off 5, For example, after 20 seconds, the filling level of the lye container at that time is 2 recorded.

[0045] To determine the average volume flow, a corresponding volume of the liquid in the lye container is determined at the fill level that existed at the defined time. 2is or was at this time. The value of this volume, which corresponds to the fill level of the lye container 2 corresponds, can be known in particular from a previous determination. Since at the time the circulation pump is switched off 5 the fill level of the suds container 2 was zero, the volume determined at the defined time corresponds to the volume that has been measured since the circulation pump was switched off 5 from the textiles 6 was expelled. The corresponding times, ie the time of switching off the circulation pump 5 on the one hand and the defined time 20 seconds after switching off the circulation pump 5 on the other hand, mark the beginning and end of an expulsion period, over the duration of which the determined volume from the textiles 6was expelled. The expulsion period in this case is 20 seconds. The average volume flow is finally determined by dividing the measured volume by the expulsion period.

[0046] In the example shown, the ejection speed 12 by means of the control device 9 automatically adjusted, whereby the selection of the expulsion speed 12 depending on both the volume or the amount of the solution in the tub 2 introduced liquid, which is measured by the inlet sensor 10 was recorded, as well as the mass of the 4 textiles 6. The selection of the expulsion speed 12 is based on empirical models based on the control device 9 are deposited. List of reference symbols

[0047] 1 Washing machine 2 Tub 3 Rotation axis 4 Washing drum 5 Circulation pump 6 Textiles 7 Liquid line 8 Fill level sensor 9 Control unit 10 Inlet sensor 11 Base speed 12 Expulsion speed 13 Floor 14 Supply line 15 Pump 16 Speed ​​curve 17 x-axis 18 y-axis

Claims

1. Method for operating a washing machine (1), the washing machine (1) comprising - a suds container (2), - a washing drum (4) arranged in the suds container (2) and rotationally drivable about an axis of rotation (3), - a drum drive for rotationally driving the washing drum (4) about its axis of rotation (3), - a circulation pump (5) for pumping liquid in the suds container (2) onto textiles (6) in the washing drum (4), - at least one level sensor (8) for capturing information relating to a fill level of liquid in the suds container (2), - a control device (9), the method comprising the following method steps: a) the washing drum (4) is rotationally driven about its axis of rotation (3) at a base rotational speed (11); b) the circulation pump (5) is operated to pump liquid in the suds container (2) onto the textiles (6) until the information captured by the level sensor (8) indicates that the fill level of the suds container (2) has reached a previously defined value; c) after the fill level has reached the defined value, the circulation pump (5) is switched off; d) the washing drum (4) continues to be rotated, whereby liquid is expelled from the textiles (8) and collects in the suds container (2), wherein the speed of the washing drum (4) is increased from the base rotational speed (11) to an expulsion rotational speed (12); e) information relating to the fill level of the suds container (2) is captured by means of the level sensor (8) and transmitted to the control device (9); f) the information is processed by means of the control device (9) in such a way that a volume of expelled liquid, which is determined on the basis of at least one fill level, is divided by a duration of an expulsion period, whereby a volume flow of the expelled liquid averaged over the expulsion period is determined.

2. Method according to claim 1, characterised in that the fill level at which the circulation pump (5) is switched off is 0 mm water column.

3. Method according to either claim 1 or 2, characterised in that the expulsion period begins at the same time as when the circulation pump (5) is switched off, or after the circulation pump (5) is switched off.

4. Method according to claim 3, characterised in that the washing drum (4) is operated at the expulsion rotational speed (12) at least during part of the expulsion period, preferably during the entire expulsion period.

5. Method according to any of the preceding claims, characterised by a preparation stage in which the rotational speed of the washing drum (4) is gradually increased to the base rotational speed (11) with the circulation pump (5) switched off.

6. Method according to claim 5, characterised in that the rotational speed of the washing drum (4) at which the fill level of the suds container (2) reaches a previously defined value is defined as the base rotational speed (11), wherein the increase in the rotational speed is preferably terminated at the moment the value is reached, so that the rotational speed of the washing drum (4) remains at least temporarily at the level of the base rotational speed (11).

7. Method according to any of the preceding claims, characterised in that a mass of all textiles (6) in the washing drum (4) is determined, in particular by means of a mass inertia method, wherein the mass of the textiles (6) is determined preferably while they are in a dry state.

8. Method according to claim 7, characterised in that the expulsion rotational speed (12) is automatically selected by means of the control device (9) depending on the mass of all textiles in the washing drum (4).

9. Method according to any of the preceding claims, characterised in that a quantity of the liquid introduced into the suds container (2) is detected, in particular by means of an inlet sensor (10).

10. Method according to claim 9, characterised in that the expulsion rotational speed (12) is automatically selected by means of the control device (9) depending on the quantity of liquid introduced into the suds container (2).

11. Method according to claims 8 and 10, characterised in that the expulsion rotational speed (12) is automatically selected by means of the control device (9) depending on both the mass of all textiles in the washing drum (4) and the quantity of liquid introduced into the suds container (2).

12. Washing machine (1) for washing textiles (6), comprising - a suds container (2), - a washing drum (4) arranged in the suds container (2) and rotationally drivable about an axis of rotation (3), - a drum drive for rotationally driving the washing drum (4) about its axis of rotation (3), - a circulation pump (5) for pumping liquid in the suds container (2) onto textiles (6) in the washing drum (4), - at least one level sensor (8) for capturing information relating to a fill level of liquid in the suds container (2), - a control device (9), wherein the control device (9) is connected to the level sensor (8) in a data-transmitting manner, wherein the control device (9) is provided and configured to operate the drum drive and the circulation pump (5), depending on the information captured by the level sensor (8), as follows: a) the washing drum (4) is rotationally driven about its axis of rotation (3) at a base rotational speed (11); b) the circulation pump (5) is operated to pump liquid in the suds container (2) onto the textiles (6) until the information captured by the level sensor (8) indicates that the fill level of the suds container (2) has reached a previously defined value; c) after the fill level has reached the defined value, the circulation pump (5) is switched off; d) the washing drum (4) continues to be rotated, whereby liquid is expelled from the textiles (8) and collects in the suds container (2), wherein the speed of the washing drum (4) is increased from the base rotational speed (11) to an expulsion rotational speed (12); e) information relating to the fill level of the suds container (2) is captured by means of the level sensor (8) and transmitted to the control device (9); f) the information is processed by means of the control device (9) in such a way that a volume of expelled liquid, which is determined on the basis of at least one fill level, is divided by a duration of an expulsion period, whereby a volume flow of the expelled liquid averaged over the expulsion period is determined.

13. Washing machine (1) according to claim 12, characterised by at least one inlet sensor (10) for capturing information relating to a quantity of liquid introduced into the suds container (2).

14. Washing machine (1) according to claim 12 or 13, characterised in that the level sensor (8) is a pressure sensor, wherein the level sensor (8) is preferably arranged in a base region of a base (13) of the suds container (2).

Images