EP3320138B1 - Laundry care apparatus and laundry care method - Google Patents

Description

The present invention relates to a laundry care device and a laundry care method.

In the context of the present invention, a laundry care appliance is in particular a washing machine, but can also be, for example, a machine for rinsing and / or impregnating laundry items. These additional functions can also be integrated in a washing machine.

The disclosure EP 2 703 537 A1 shows a washing machine.

The disclosure EP 2 161 365 A2 shows a washing machine.

The disclosure EP 1 867 773 A1 shows a washing machine.

As part of a laundry care program of a laundry care device, such as a washing machine, a detergent from a detergent receptacle together with fresh water is washed into the laundry drum of the laundry care device during a washing-in process by means of a washing-in device, in order to wash the laundry items in the laundry drum with the mixture of detergent and fresh water is also referred to herein as alkali or washing liquid. In order to ensure an in-depth and as uniform as possible wetting or moistening of the laundry items with the washing liquid, it is eg from the DE3401899A1 known to discharge washing liquid from the laundry drum or a tub connected to the laundry drum by means of a pumping device and to apply it again to the laundry items in the laundry drum via a nozzle. In the DE3401899A1 a heating element is also described, which is arranged on the bottom of the tub and with which the washing liquid can be heated to a target temperature.

At the in the DE3401899A1 described washing machine, however, the problem may arise that the heating element is exposed during a pumping process and can be damaged. A solution to this problem is in the EP1204792B1 described. At the in the EP1204792B1 However, the solution described uses technically relatively complex means.

The disclosure DE 10 2013 106 091 A1 shows a washing method and a washing machine.

The disclosure EP 2 246 469 A1 shows a washing machine.

The disclosure EP 0 464 776 A1 shows a protective mechanism for a heating element of a washing machine.

It is the object on which the invention is based to specify a laundry care appliance and a laundry care method which, in particular in the light of the disadvantages described above, enable more efficient care of laundry items.

This object is achieved by objects with the features according to the independent claims. Advantageous embodiments of the invention are the subject of the figures, the description and the dependent claims.

According to a first aspect of the invention, the object is achieved by a laundry care device with a rotatably mounted laundry drum for receiving items of laundry, a drive motor for rotating the laundry drum, a pumping device for recirculating washing liquid out of the laundry drum and back into the laundry drum, and a heating element for Heating the washing liquid and a control device for controlling the drive motor, the pumping device and the heating element in accordance with a laundry care program running on the control device during operation. The control device is designed to deactivate the pumping device when the heating element is activated as soon as the amount of washing liquid in the washing drum or in a tub in which the washing drum is rotatably mounted falls below a minimum amount threshold. This has the advantage according to the invention that a protective mechanism is provided which protects the heating element against overheating, since it is always covered by a minimum amount of washing liquid.

In an advantageous embodiment, the control device is designed, as part of the laundry care program, which provides phases in which the laundry drum is rotated at a speed in the range of the application speeds and the Pumping device is active to activate the pumping device only when the speed of the laundry drum is ramped up when the speed of the laundry drum exceeds a first speed threshold value. This achieves the technical advantage, for example, that it can be ensured without great technical effort that the amount of washing liquid in the washing drum or a tub in which the washing drum is rotatably mounted is always large enough for the pump of the pumping device to operate without problems can be, in particular no air. At speeds of the laundry drum below the first speed threshold, it can happen that the majority of the washing liquid is bound in the items of laundry.

In an advantageous embodiment, the control device is designed to deactivate the pump-around device when the speed of the laundry drum is reduced when the speed of the laundry drum falls below a second speed threshold value. This also achieves the technical advantage, for example, that it can be ensured without great technical effort that the amount of washing liquid in the laundry drum or in a tub in which the washing drum is rotatably mounted is always large enough for the pump of the pumping device to be fault-free can be operated, in particular no air is drawn.

The first speed threshold can be equal to the second speed threshold. Studies have shown that the first and / or the second speed threshold value should preferably be greater than approximately 50 rpm. An application speed can be, for example, in a range from approximately 80 to approximately 500 rpm.

In an advantageous embodiment, the control device is designed to continuously adapt the first and / or the second speed threshold value to the amount of washing liquid in the washing drum, the first and / or the speed threshold value being lowered for a larger amount of washing liquid and for a smaller amount the washing liquid the first and / or the second speed threshold value is increased. This has the technical advantage, for example, that the laundry care program is better suited to a particular wash cycle essentially defined by the type and amount of laundry items can be customized.

In an advantageous embodiment, the laundry care device further comprises a pressure sensor, which is designed to detect the pressure of the washing liquid in the laundry drum or the tub in which the laundry drum is rotatably mounted, the control device being designed to, when the heating element is activated, the pumping device deactivate as soon as the pressure detected by the pressure sensor falls below a pressure threshold. This has the advantage, for example, that technically simple means provide an additional protective mechanism which protects the heating element from overheating.

In an advantageous embodiment, the control device is designed to cycle at least two cycles in which the rotation of the laundry drum is raised to a placement speed and lowered again, the pumping device is activated above the first speed threshold value and deactivated below the second speed threshold value, and the heating element is activated Times in a row. This has the advantage, for example, that a more uniform temperature distribution is generated in the washing liquid and the laundry items.

In an advantageous embodiment, the control device is designed to activate the cycle in which the rotation of the laundry drum is raised to a placement speed and then lowered again, the pumping device is activated above the first speed threshold value and deactivated below the second speed threshold value, and the heating element is activated as long as repeat until a substantially uniform temperature distribution is achieved at a desired target temperature. This has the advantage, for example, that an even temperature distribution is generated in the washing liquid and the laundry items.

In one embodiment, as soon as a substantially uniform temperature distribution at the desired target temperature has been reached, the control device is designed to deactivate the heating element and at least once more to rotate the laundry drum up to a contact speed and again drive down, the pumping device being activated above the first speed threshold and the pumping device being deactivated below the second speed threshold. This has the advantage, for example, that an even temperature distribution is generated in the washing liquid and the laundry items.

In one embodiment it is provided that the control device is designed to operate the pumping device continuously when the heating element is activated. This means that the pumping device is operated continuously until the amount of washing liquid in the laundry drum falls below the minimum amount threshold. This results in efficient pumping, for example.

Continuously means the opposite of impulsive. This means that the pumping device remains activated until the amount of washing liquid in the laundry drum falls below the minimum amount threshold.

According to a second aspect of the invention, the object is achieved by a laundry care method for a laundry care device with a rotatably mounted laundry drum for receiving items of laundry, a drive motor for rotating the laundry drum, a pumping device for recirculating washing liquid out of the laundry drum and back into the laundry drum, a heating element for heating the washing liquid and a control device for controlling the drive motor, the pumping device and the heating element according to a laundry care program running on the control device during operation. The laundry care method comprises the step that the control device deactivates the pump-around device when the heating element is activated as soon as the amount of washing liquid in the laundry drum or a tub in which the laundry drum is rotatably mounted falls below a minimum amount threshold. This achieves the advantage according to the invention that a protective mechanism is provided which protects the heating element against overheating.

In an advantageous embodiment, the control device activates as part of the laundry care program, which provides phases in which the laundry drum with a Rotation speed in the range of application speeds is rotated and the pumping device is active, the pumping device when the speed of the laundry drum is ramped up only when the speed of the laundry drum exceeds a first speed threshold value. This achieves the technical advantage, for example, that it can be ensured without great technical effort that the amount of washing liquid in the washing drum or a tub in which the washing drum is rotatably mounted is always large enough for the pump of the pumping device to operate without problems can be, in particular no air. At speeds of the laundry drum below the first speed threshold, it can happen that the majority of the washing liquid is bound in the items of laundry.

In an advantageous embodiment, the control device deactivates the pump-around device when the speed of the laundry drum is reduced when the speed of the laundry drum falls below a second speed threshold. This also achieves the technical advantage, for example, that it can be ensured without great technical effort that the amount of washing liquid in the laundry drum or in a tub in which the washing drum is rotatably mounted is always large enough for the pump of the pumping device to be fault-free can be operated, in particular no air is drawn.

The first speed threshold can be equal to the second speed threshold. Studies have shown that the first and / or the second speed threshold value should preferably be greater than approximately 50 rpm. An application speed can be, for example, in a range from approximately 80 to approximately 500 rpm.

In an advantageous embodiment, the control device continuously adjusts the first and / or the second speed threshold value to the amount of washing liquid in the washing drum or the tub, the first and / or the speed threshold value being lowered for a larger amount of washing liquid and for a smaller one Amount of washing liquid the first and / or the second speed threshold value is increased. This has the technical advantage, for example, that the laundry care program is better suited to a particular wash cycle essentially defined by the type and amount of laundry items can be customized.

In an advantageous embodiment, the laundry care method further comprises the step of detecting the pressure of the washing liquid in the laundry drum or the tub in which the laundry drum is rotatably mounted, the control device deactivating the pumping device when the heating element is activated as soon as the detected pressure falls below a pressure threshold falls. This has the advantage, for example, that technically simple means provide an additional protective mechanism which protects the heating element from overheating.

In an advantageous embodiment, the control device carries out a cycle in which the rotation of the laundry drum is raised to a placement speed and lowered again, the pumping device is activated above the first speed threshold value and deactivated below the second speed threshold value, and the heating element is activated, at least twice in succession , This has the advantage, for example, that a more uniform temperature distribution is generated in the washing liquid and the laundry items.

In an advantageous embodiment, the control device repeats the cycle in which the rotation of the laundry drum is ramped up to a feed speed and is lowered again, the pumping device is activated above the first speed threshold value and deactivated below the second speed threshold value, and the heating element is activated until an im Substantially uniform temperature distribution is achieved at a desired target temperature. This has the advantage, for example, that an even temperature distribution is generated in the washing liquid and the laundry items.

In one embodiment, the control device deactivates the heating element as soon as an essentially uniform temperature distribution is achieved at the desired target temperature, and the rotation of the laundry drum is at least once again increased and decreased to a contact speed, the pumping device being activated above the first speed threshold value and the pumping device is deactivated below the second speed threshold. This will For example, the advantage is achieved that a uniform temperature distribution is generated in the washing liquid and the laundry items.

In one embodiment it is provided that the control device operates the pumping device continuously when the heating element is activated. This means that the pumping device is operated continuously until the amount of washing liquid in the laundry drum falls below the minimum amount threshold. This results in efficient pumping, for example.

Continuously means the opposite of impulsive. This means that the pumping device remains activated until the amount of washing liquid in the laundry drum falls below the minimum amount threshold.

Technical functionalities of the laundry care method result directly analogously from corresponding technical functionalities of the laundry care device and vice versa.

In one embodiment it is provided that the laundry care method is carried out or carried out by means of the laundry care device.

In one embodiment, the laundry care device is designed or set up to carry out or carry out the laundry care process.

Further exemplary embodiments of the invention are shown in the drawings and are described in more detail below.

Fig. 1

eine schematische Ansicht eines Wäschepflegegeräts;

Fig. 2

ein beispielhaftes schematisches Diagramm, das den zeitlichen Verlauf mehrerer Größen bei einem Wäschepflegeverfahren veranschaulicht;

Fig. 3

eine Detailansicht eines Ausschnitts des schematischen Diagramms von Figur 2;

Fig. 4

ein beispielhaftes schematisches Diagramm, das den zeitlichen Verlauf mehrerer Größen während einer Einspülphase eines Wäschepflegeverfahrens veranschaulicht; und

Fig. 5

ein beispielhaftes schematisches Diagramm, das den zeitlichen Druckverlauf für zwei unterschiedliche Beladungen während einer Einspülphase eines Wäschepflegeverfahrens bei einem Wäschepflegegerät in Form einer Waschmaschine gemäß einer Ausführungsform und einer herkömmlichen Waschmaschine veranschaulicht.

Show it:

Fig. 1

a schematic view of a laundry care device;

Fig. 2

an exemplary schematic diagram illustrating the temporal course of several sizes in a laundry care process;

Fig. 3

a detailed view of a section of the schematic diagram of Figure 2 ;

Fig. 4

an exemplary schematic diagram illustrating the temporal course of several variables during a washing phase of a laundry care method; and

Fig. 5

an exemplary schematic diagram illustrating the pressure over time for two different loads during a wash-in phase of a laundry care method in a laundry care device in the form of a washing machine according to one embodiment and a conventional washing machine.

Figure 1 shows a schematic representation of a washing machine representative of a general laundry care device 100. The laundry care device 100 in the form of a washing machine is used to wash items of laundry and similar laundry items with a detergent. In this case, the washing machine can optionally also be configured as a washer dryer in order to wash and dry laundry or similar laundry items. In the context of the invention, in addition to conventional detergents, the term “detergent” also includes treatment additives such as fabric softener, rinse aid or odor-improving agent in various forms (liquid, gel-like, pasty or also powder-like).

The washing machine 100 from Figure 1 contains in a machine housing 102 a tub 104 fixed in the machine housing. A laundry drum 106 is rotatably mounted in the tub 104 about a horizontal axis of rotation and can be set in rotation at different speeds by means of a drive motor 105 which can be controlled by an electronic control device 118. In the laundry drum 106, items of laundry 108 are indicated, which are lifted when the laundry drum 106 is rotated by carriers 110 on the inside of the laundry drum 106 and fall down again. As a result, the laundry items 108 are constantly rearranged when the laundry drum 106 rotates.

Fresh water can be fed from a fresh water line 112 through a detergent container 116, for example in the form of an inlet valve, through a detergent dispenser 116, which can be designed, for example, as a induction bowl and in addition to conventional ones Detergents can also contain treatment additives such as fabric softener, rinse aid, odor improver or other laundry treatment agent in various forms (liquid, gel-like, pasty or also powder-like), either directly (as in the Figure 1 schematically shown) or be introduced into the laundry drum 106 via the tub 104. The mixture of fresh water and detergent is referred to herein as washing liquid or lye. To control the fresh water supply, the induction device 114 is also connected to the electronic control device 118.

The tub 104 is provided at its lower end with a downwardly shaped trough 128 which forms a heating chamber 130. An electrical heating element 132 is arranged in the heating chamber 130, preferably a tubular heating element with which the washing liquid in the tub 104 can be heated. To control the electrical heating element 132, this is also connected to the electronic control device 118, as shown in FIG Figure 1 is shown schematically.

At the bottom of the depression 128 of the tub 104, a tub drain 134 is provided, which is connected on the one hand to a pumping device 120 and on the other hand to a pumping device 144.

The pumping device 120, which serves in particular to flood the laundry items 108 several times with the washing liquid, comprises a pump 122, a suction line 124 on the suction side and a pressure line 126 on the pressure side of the pump 122 the lower end of the tub 104 can be recirculated back into the laundry drum 106 onto the laundry items 108. The washing liquid supplied via the pressure line 126 to the pumping device 120 is applied to the laundry items 108 in the laundry drum 106 via a nozzle. To control the pumping device 120, in particular the pump 122, this is also connected to the electronic control device 118, as shown in FIG Figure 1 is shown schematically.

The pumping device 144, which is used in particular to pump out washing liquid located in the tub 104 and to discharge it from the washing machine 100, comprises a pump 142 with a suction line 140 and a pressure line 146 Activation of the pumping device 144, in particular the pump 142, can also be connected to the electronic control device 118.

An embodiment of the electronic control device 118 according to the invention and its interaction with the components of the laundry care appliance 100 described above is described in detail below in the context of an inventive laundry care method with further reference to FIG Figures 2 and 3 described.

Figure 2 shows a schematic diagram that illustrates the time course of several variables in a laundry care method according to the invention, namely the time course of the activity of the pump 122 of the pumping device 120 (ie pump 122 on or off), the speed of the laundry drum 106 and the temperature of the washing liquid.

According to the invention, the control device 118 is designed to deactivate the pumping device 120 as part of the laundry care program when the heating element 132 is activated as soon as the amount of washing liquid in the laundry drum 106 or the tub 104 falls below a minimum amount threshold. This has the advantage, for example, that an additional protective mechanism is provided which protects the heating element 132 against overheating.

In an advantageous embodiment, the control device 118 is designed, in the context of the laundry care program, which provides phases in which the laundry drum 106 is rotated at a speed in the range of the application speeds and the pumping device 120 is to be activated, the pumping device 120 when the speed of the Only activate the laundry drum 106 when the speed of the laundry drum 106 exceeds a first speed threshold.

In Figure 2 Two such phases are shown in which the laundry drum 106 is rotated at a speed in the range of the application speeds and the pumping device 120 is active. A detailed view of section A from Figure 2 is in Figure 3 shown. By means of the configuration according to the invention, the pumping device 120 is only activated when the rotational speed of the laundry drum 106 is increased when the rotational speed of the Washing drum 106 exceeds a first speed threshold value, the technical advantage is achieved, for example, that it can be ensured without great technical effort that the amount of washing liquid in the suds container 104 is always large enough that the pump 122 of the pumping device 120 can be operated without problems, that is especially no air. At speeds of the laundry drum 106 below the first speed threshold value, it can happen that the majority of the washing liquid is bound in the items of laundry.

In an advantageous embodiment, the control device 118 is designed to deactivate the pumping device 120 when the speed of the laundry drum 106 is reduced when the speed of the laundry drum 106 falls below a second speed threshold value. This also achieves the technical advantage, for example, that it can be ensured without great technical effort that the amount of washing liquid in the suds container 104 is always large enough that the pump 122 of the pumping device 120 can be operated without problems, in particular that it does not draw air.

The first speed threshold can be equal to the second speed threshold. Studies have shown that the first and / or the second speed threshold value should preferably be greater than approximately 50 rpm. An application speed can be, for example, in a range from approximately 80 to approximately 500 rpm.

In an advantageous embodiment, the control device 118 is designed to continuously adapt the first and / or the second speed threshold value to the amount of the washing liquid in the washing drum 106 and / or the tub 104, the first and / or the for a larger amount of the washing liquid Speed threshold is lowered and the first and / or the second speed threshold is increased for a smaller amount of washing liquid. In this way, for example, the technical advantage is achieved that the laundry care program can be better adapted to a particular wash cycle, which is essentially defined by the type and amount of the laundry items 108.

In an advantageous embodiment, the laundry care device 100 further comprises a pressure sensor, which is designed to detect the pressure of the washing liquid in the laundry drum 106 or in the tub 104, the control device 118 being designed to deactivate the pumping device 120 when the heating element 132 is activated , as soon as the pressure detected by the pressure sensor falls below a pressure threshold. This achieves the advantage, for example, that an additional protective mechanism is provided using technically simple means, which protects the heating element 132 against overheating.

In an advantageous embodiment, the control device 118 is designed to perform a cycle in which the rotation of the laundry drum 106 is ramped up and down again to a contact speed, the pumping device 120 is activated above the first speed threshold value and deactivated below the second speed threshold value, and the heating element 132 is activated is to perform at least twice in a row. This has the advantage, for example, that a more uniform temperature distribution is generated in the washing liquid and the laundry items 108.

In an advantageous embodiment, the control device 118 is designed to activate the pumping device 120 above the first speed threshold value and below the second speed threshold value, and activate the heating element 132, and the heating element 132 is activated, the cycle in which the rotation of the laundry drum 106 is raised to a feed speed and lowered again is to be repeated until an essentially uniform temperature distribution is achieved at a desired target temperature. This has the advantage, for example, that an even temperature distribution is generated in the washing liquid and the laundry items 108.

In one embodiment, as soon as a substantially uniform temperature distribution at the desired target temperature is reached, the control device 118 is designed to deactivate the heating element 132 and to increase and decrease the rotation of the laundry drum 106 at least once more to a contact speed, above the first speed threshold pumping device 120 is activated and below the second speed threshold the pumping device 120 is deactivated. This has the advantage, for example, that an even temperature distribution is generated in the washing liquid and the laundry items 108.

Figure 4 shows a schematic diagram which illustrates the course over time of several variables in a laundry care process, namely the course over time of the amount of water supplied via the dispenser 114, the activity of the pump 122 of the pumping device 120, the speed of the laundry drum 106 and the temperature of the washing liquid. How this is recognized by the expert shows in Figure 4 Diagram shown shows a washing-in phase of the laundry care method, in which fresh water or washing liquid is added to the washing drum 106 in several successive washing-in processes, as described above, for example, from the fresh water line 112 via the washing-in device 114 and the detergent container 116 Washing-in processes separated by periods in which no further fresh water is added to the washing drum 106 via the washing-in device 114, ie the washing-in device 114 is deactivated or closed.

By way of example, the control device 118 is designed to, at the end of one of the FIGS Figure 4 illustrated washing processes of the laundry care program, in which fresh water and detergent are flushed into the washing drum 106 by means of the washing device 114, to control the drive motor 105 of the washing drum 106 in such a way that the drive motor 105 drives the washing drum 106 reversibly over a first reversing period, and after the drive motor 105 when the pumping device 120 is deactivated, the laundry drum 106 has reversed at least once during the first reversing period, ie has rotated in one direction of rotation and in the opposite direction of rotation, to activate the pumping device 120 and to deactivate it at the end of a second pumping period 120. The laundry drum 106 can first be brought up to a speed of, for example, 55 rpm in one direction of rotation and then to a speed of, for example, 55 rpm in the opposite direction of rotation. In this way it is achieved that in particular the items 108 lying on the inside of the laundry drum 106 are wetted with washing liquid via the jacket of the laundry drum 106.

In Figure 4 the reversing of the laundry drum 106 can be recognized, for example, by the two peaks and valleys of the speed curve before the rest phases identified by the numbers "1", "2", "3" or "4". In Figure 4 a second pumping period in which the pumping device 120 is active falls with a part of the in FIG Figure 4 periods marked with the letters "B", "C", "D" and "E".

In one embodiment, the control device 118 can be designed to, in the context of the first flushing-in process in FIG Figure 4 shown to substantially simultaneously activate the induction device 114 and the pumping device 120. The corresponding first pumping period over which pumping device 120 is operated by control device 118 is shown in FIG Figure 4 marked with the letter "A". The duration of the in Figure 4 The first pumping period marked with the letter "A" can only be a few seconds. The duration of the first pumping period can be shorter than the duration of the first flushing period.

The essentially simultaneous rinsing and pumping ensures that detergent residues which have not been dissolved so far are actively mixed with the washing liquid and less detergent residues which have not been dissolved so far are deposited in parts of the laundry care appliance 100, in particular on the bottom of the suds container 104 and / or in the tub-shaped suds container drain 134 , It is known from practice that the major portion of the detergent is flushed into the tub 104 together with the first four liters of fresh water.

The control device 118 can furthermore be designed to control the drive motor 105 of the laundry drum 106 in such a way that the laundry drum 106 is at least temporarily rotated at the application speed during the second pumping-over period described above. Such a rotation of the laundry drum 106 at the application speed is shown in FIG Figure 4 shown in the period "D". The application speed can be, for example, in a range from approximately 80 to approximately 500 rpm. The rotation of the laundry drum 106 at this time, that is to say with simultaneous pumping, at the application speed leads to the items of laundry lying against the inside of the laundry drum due to the centrifugal forces and the washing liquid introduced into the laundry drum 106 by the pumping device 120 directly onto the washing liquid on the inside of the Laundry drum 106 fits adjacent jacket of laundry items 108. This ensures uniform wetting or moistening of almost all items of laundry 108 (even when the laundry drum 106 is fully loaded). Due to the centrifugal forces that occur during rotation at the application speed, the washing liquid is also pressed out of the laundry items 108 and is returned to the laundry drum 106 via the active pumping device 120 for further wetting of the laundry items 108.

In one embodiment, both the above-described first reversing period and the above-described second pumping period end essentially simultaneously, as can be seen in FIG Figure 4 from the end of the respective periods "B", "C", "D" and "E". In a preferred embodiment, a respective rest phase begins with the simultaneous end of a first reversing period and a second pumping period. Four such periods of rest are in Figure 4 marked with the digits "1", "2", "3" and "4". In a preferred embodiment, the induction device 114 is also inactive during the respective resting phases "1" to "4".

In one embodiment, the control device 118 is designed to, after the end of a first reversing period and a second pumping period, that is to say during a rest phase following the first reversing period and the second pumping period, for example in FIG Figure 4 shown rest phases "1", "2", "3" or "4", to detect the pressure of the washing liquid in the laundry drum 106 or the tub 104 and to adjust parameters of the laundry care program running on the control device 118 on the basis of this pressure. This has the technical advantage, for example, that parameters of the laundry care program can be adapted to the actual load, for example in order to reduce energy consumption. For the detection of the pressure of the washing liquid in the tub 104, for example, a pressure sensor can be provided in the depression 128 of the tub 104, which is connected to the control device 118.

Figure 5 FIG. 3 shows an exemplary schematic diagram that shows the pressure curve over time for two different loads, namely a full load and a half load, during part of the process shown in FIG Figure 4 illustrated washing phase in a laundry care device in the form of a washing machine 100 according to one embodiment (on the upper side) and a conventional washing machine (on the lower side). The uniform parts of the respective curve shape which initially rise sharply and then flatten out correspond to those in FIG Figure 4 illustrated rest phases, whereby in Figure 5 two rest phases are shown. How the Figure 5 With a laundry care device in the form of a washing machine 100 according to one embodiment, which is operated, for example, as described above, a minimum pressure delta required for load differentiation is reached at an earlier point in time t ₀ than in a conventional washing machine, in which this is done for load differentiation required minimum pressure delta is only reached at a later time t ₀ '. A washing machine 100 operated as described above, for example, thus permits a faster and better estimate of the load than conventional washing machines, as a result of which the overall duration of the laundry care program can be reduced and the laundry care program can be adapted more quickly and better to the actual load, which in turn improves the washing result and energy consumption can be reduced.

Alternatively or additionally, the control device 118 can be designed to operate the pumping device 120 during the second pumping period in such a way that the volume flow conveyed by the pumping device 120 is not less than a dripping speed of the laundry items 108. This has the technical advantage, for example, that already at the beginning of the rest phase initiated by the deactivation of the drive motor 105 and the pumping device 120, for example at the beginning of FIG Figure 4 shown rest phases "1", "2", "3" or "4", the loading of the laundry care device 100 by the laundry items 108 can be estimated from the pressure of the washing liquid in the tub 104.

All of the features explained and shown in connection with individual embodiments of the invention can be provided in different combinations in the subject matter of the invention in order to simultaneously realize their advantageous effects.

The scope of the present invention is given by the claims and is not limited by the features explained in the description or shown in the figures.

LIST OF REFERENCE NUMBERS

100

Laundry care device

102

machine housing

104

tub

105

drive motor

106

washing drum

108

laundry

110

takeaway

112

Fresh water pipe

114

Flushing device

116

detergent container

118

control device

120

Umpumpvorrichtung

122

pump

124

suction

126

pressure line

128

trough

130

heating chamber

132

heating element

134

Tub drain

140

suction

142

pump

144

pumping device

146

pressure line

Claims (15)

1. Laundry care appliance (100) with a rotatably mounted laundry drum (106) for receiving laundry items (108), a drive motor (105) for rotating the laundry drum (106), a repumping apparatus (120) for recirculating wash liquid out from the laundry drum (106) and back into the laundry drum (106), a heating element (132) for heating the wash liquid and a control device (118) for actuating the drive motor (105), the repumping apparatus (120) and the heating element (132) in accordance with a laundry care program running on the control device (118) during operation,
   characterised in that
   the control device (118) is embodied, when the heating element (132) is activated, to deactivate the repumping apparatus (120) as soon as the amount of wash liquid in the laundry drum (106) falls below a minimum amount threshold value, so that a protection mechanism is provided which protects the heating element (132) from overheating by always covering it with a minimum amount of wash liquid.
2. Laundry care appliance (100) according to claim 1, wherein the control device (118) is embodied, as part of the laundry care program, which provides phases in which the laundry drum (106) is rotated with a rotational speed in the range of setting speeds and the repumping apparatus (120) is active, to then activate the repumping apparatus (120) while ramping up the rotational speed of the laundry drum (106) when the rotational speed of the laundry drum (106) exceeds a first rotational speed threshold value.
3. Laundry care appliance (100) according to claim 2, characterised in that the control device (118) is embodied to then deactivate the repumping apparatus (120) while ramping down the rotational speed of the laundry drum (106) when the rotational speed of the laundry drum (106) falls below a second rotational speed threshold value.
4. Laundry care appliance (100) according to claim 2 or 3, characterised in that the control device (118) is embodied to adapt the first and/or the second rotational speed threshold value to the amount of wash liquid in the laundry drum (106), wherein for a larger amount of wash liquid, the first and/or the second rotational speed threshold value is lowered and for a smaller amount of wash liquid, the first and/or the second rotational speed threshold value is increased.
5. Laundry care appliance (100) according to one of the preceding claims, characterised in that the laundry care appliance (100) further comprises a pressure sensor, which is embodied to record the pressure of the wash liquid in the laundry drum (106), wherein the control device (118) is embodied, when the heating element (132) is activated, to deactivate the repumping apparatus (120) as soon as the pressure recorded by the pressure sensor falls below a pressure threshold value.
6. Laundry care appliance (100) according to one of the preceding claims, characterised in that the laundry care appliance (118) is embodied to perform a cycle, in which the rotation of the laundry drum (106) is ramped up to a setting speed and ramped down again, the repumping apparatus (120) is activated above the first rotational speed threshold value and deactivated below the second rotational speed threshold value and the heating element (132) is activated, at least two times in succession.
7. Laundry care appliance (100) according to claim 6, characterised in that the control device (118) is embodied to repeat the cycle until a substantially even temperature distribution at a desired target temperature is achieved.
8. Laundry care appliance (100) according to claim 5 or 6, characterised in that the control device (118) is embodied, as soon as a substantially even temperature distribution at the desired target temperature is achieved, to deactivate the heating element (132) and to ramp up the rotation of the laundry drum (106) at least one more time to a setting speed and ramp it down again, wherein the repumping apparatus (120) is activated above the first rotational speed value and the repumping apparatus (120) is deactivated below the second rotational speed value.
9. Laundry care method for a laundry care appliance (100) with a rotatably mounted laundry drum (106) for receiving laundry items (108), a drive motor (105) for rotating the laundry drum (106), a repumping apparatus (120) for recirculating wash liquid out from the laundry drum (106) and back into the laundry drum (106), a heating element (132) for heating the wash liquid and a control device (118) for actuating the drive motor (105), the repumping apparatus (120) and the heating element (132) in accordance with a laundry care program running on the control device (118) during operation,
   characterised in that
   the laundry care method comprises the step that, when the heating element (132) is activated, the control device (118) deactivates the repumping apparatus (120) as soon as the amount of wash liquid in the laundry drum (106) falls below a minimum amount threshold value, so that a protection mechanism is provided which protects the heating element (132) from overheating by always covering it with a minimum amount of wash liquid.
10. Laundry care method according to claim 9, characterised in that as part of the laundry care program, which provides phases in which the laundry drum (106) is rotated with a rotational speed in the range of setting speeds and the repumping apparatus (120) is active, to then activate the repumping apparatus (120) while ramping up the rotational speed of the laundry drum (106) when the rotational speed of the laundry drum (106) exceeds a first rotational speed threshold value.
11. Laundry care method according to claim 10, characterised in that the control device (118) then deactivates the repumping apparatus (120) while ramping down the rotational speed of the laundry drum (106) when the rotational speed of the laundry drum (106) falls below a second rotational speed threshold value.
12. Laundry care method according to claim 10 or 11, characterised in that the control device (118) adapts the first and/or the second rotational speed threshold value to the amount of wash liquid in the laundry drum (106), wherein for a larger amount of wash liquid, the first and/or the second rotational speed threshold value is lowered and for a smaller amount of wash liquid, the first and/or the second rotational speed threshold value is increased.
13. Laundry care method according to one of claims 9 to 12, characterised in that the laundry care method further comprises the step of recording the pressure of the wash liquid in the laundry drum (106) by means of a pressure sensor, wherein the control device (118), when the heating element (132) is activated, deactivates the repumping apparatus (120) as soon as the pressure recorded by the pressure sensor falls below a pressure threshold value
14. Laundry care method according to one of claims 9 to 13, characterised in that the control device (118) performs a cycle, in which the rotation of the laundry drum (106) is ramped up to a setting speed and ramped down again, the repumping apparatus (120) is activated above the first rotational speed threshold value and deactivated below the second rotational speed threshold value and the heating element (132) is activated, at least two times in succession.
15. Laundry care method according to one of claims 9 to 14, characterised in that the control device (118), as soon as a substantially even temperature distribution at the desired target temperature is achieved, deactivates the heating element (132) and ramps up the rotation of the laundry drum (106) at least one more time to a setting speed and ramps it down again, wherein the repumping apparatus (120) is activated above the first rotational speed value and the repumping apparatus (120) is deactivated below the second rotational speed value.

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