EP3246451B2 - Method and device for operating a washing machine - Google Patents

Description

The invention relates to a method for operating a washing machine.

Some laundry care appliances may have induction heating. For laundry care appliances, for example, a comfort smoothing function with a small amount of free liquor can also be provided below a drum casing of a laundry drum. For example, heating by means of radiators can only be carried out if there is a free liquor available. Here, the free liquor can be heated and heat can be transferred to the laundry when the liquor is exchanged.

The DE 10 2014 208 514 A1 and the DE 10 2008 043281 A1 describes a laundry treatment device with induction heating. The EP 2 540 896 A1 describes a laundry treatment device with a flooding device.

The object of the invention is to provide an improved method for operating a washing machine.

According to the invention, this object is achieved by a method for operating a washing machine with the features of the main claim. Advantageous refinements and developments of the invention result from the following dependent claims.

The advantages that can be achieved with the invention consist, in addition to induction heating for washing machines and washer-dryers, in particular for washing machines and washer-dryers with a circulation function, for example, among other things, that water, detergent and energy are saved. In particular, heating without free liquor can also be made possible and damp laundry can be heated without additional consumption of additional water. In addition, switching the heating on and off in the heating step can be avoided, particularly when steam is used. No free liquor needs to be heated, which can lead to energy savings. This can be achieved in a cost-effective and structurally advantageous manner, with an electrical coil being arranged above or to the side of a tub and a drum being able to be heated evenly. In this case, the drum can be temperature-controlled, warmed up or heated up directly and as uniformly or evenly as possible. Thus, the drum can act as a heating element for tempering or heating laundry.

• Induzieren von Wirbelströmen in mindestens einer Trommelwand, um die Trommel zu erwärmen; und
• Umwälzen von aus der Wäsche ausgetriebener Waschlauge durch die Trommel, um die Wäsche mit Waschlauge zu sättigen.

A method for washing laundry is not claimed, the method being executable in connection with a washing machine, the washing machine having a drum for receiving the laundry, the drum having at least one drum wall made of a ferromagnetic material, the method having at least the following steps:

• inducing eddy currents in at least one drum wall to heat the drum; and
• circulating wash suds expelled from the laundry through the drum to saturate the laundry with wash suds.

The method can be carried out in connection with or using a non-claimed embodiment of a washing machine mentioned below. The eddy currents can be induced by means of an electrical signal applied to the at least one electrical coil. The automatic washing machine can be designed as a washing machine, a washer-dryer or the like. A drum wall can represent a drum shell. The at least one electric coil can be arranged outside of the drum. The drum may be rotatable relative to an electrical coil.

According to an embodiment not claimed, the circulating step can be carried out once or repeatedly during the inducing step. Such an embodiment offers the advantage that by heating the drum wall combined with a circulation, a uniform heat distribution in the laundry can be realized in an energy- and water-saving manner, even with large batches of laundry.

The circulating step can also be carried out once or repeatedly before and additionally or alternatively after the inducing step. In addition, the inducing step can be carried out repeatedly before, during and additionally or alternatively after the circulating step. Such an embodiment, which is not claimed, offers the advantage that the laundry can be washed with reduced or minimized use of heating energy and washing suds.

A method for operating a washing machine is presented, the washing machine having a drum for receiving laundry, the drum having at least one drum wall made of a ferromagnetic material, at least one electrical coil arranged adjacent to the drum and a flooding unit, the method has at least the following steps:
applying an electrical signal to the at least one electrical coil to induce eddy currents in the at least one drum wall to heat the drum; and issuing a flood signal to the flood unit to circulate wash suds expelled from the laundry through the drum to flood the laundry with wash suds to saturate the laundry with wash suds.

The method can be carried out in connection with or using an embodiment of a washing machine mentioned below. The method can in particular be executable by an embodiment of a device mentioned below or by a control unit.

Furthermore, according to the invention, in the application step, an electrical signal is applied which is suitable for generating a heating output which is dependent on the amount of laundry (280) loaded in the drum and on the temperature of the drum. Such an embodiment offers the advantage that the drum and thus also the laundry located therein can be heated quickly, efficiently and depending on the load.

Furthermore, the dispensing step can be carried out repeatedly before, during and additionally or alternatively after the applying step. Such an embodiment offers the advantage that by heating the drum wall combined with activated circulation, while saving energy and water, an even heat distribution can be realized in the laundry, even with large batches of laundry.

According to an embodiment that is not claimed, a high-frequency electrical alternating voltage can be applied as an electrical signal in the application step in order to generate an alternating magnetic field with which the at least one drum wall can be applied. Additionally or alternatively, the electrical signal can be pulse width modulated. Such an embodiment offers the advantage that the drum and thus also the laundry located therein can be heated quickly and efficiently.

The approach presented here also creates a device for controlling an automatic washing machine, which is designed to carry out, control or implement the steps of a variant of a method presented here in corresponding devices. The device can have an embodiment of a washing machine which is not claimed below. The object on which the invention is based can also be achieved quickly and efficiently by this embodiment variant of the invention in the form of a device.

The device can be designed to read in input signals and to determine and provide output signals using the input signals. An input signal can, for example, be read in via an input interface of the device Display sensor signal. An output signal may represent a control signal or a data signal that may be provided at an output interface of the device. The device can be designed to determine the output signals using a processing specification implemented in hardware or software. For example, the device can include a logic circuit, an integrated circuit or a software module and can be implemented as a discrete component, for example, or can be comprised of a discrete component.

• eine Trommel zum Aufnehmen der Wäsche, wobei die Trommel zumindest eine Trommelwand aus einem ferromagnetischen Material aufweist;
• zumindest eine benachbart zu der Trommel angeordnete elektrische Spule zum Induzieren von Wirbelströmen in der zumindest einen Trommelwand, um die Trommel zu erwärmen;
• eine Umflutungseinheit zum Umwälzen von aus der Wäsche ausgetriebener Waschlauge durch die Trommel zum Umfluten der Wäsche mit Waschlauge, um die Wäsche mit Waschlauge zu sättigen; und
• eine Ausführungsform der vorstehend genannten Vorrichtung, wobei die Vorrichtung ausgebildet ist, um mindestens die Trommel, die zumindest eine elektrische Spule und die Umflutungseinheit zu steuern.

A non-claimed automatic washing machine for washing laundry is also presented, the automatic washing machine having at least the following features:

• a drum for receiving the laundry, the drum having at least one drum wall made of a ferromagnetic material;
• at least one electrical coil disposed adjacent the drum for inducing eddy currents in the at least one drum wall to heat the drum;
• a flooding unit for circulating wash suds expelled from the laundry through the drum to flood the laundry with wash suds to saturate the laundry with wash suds; and
• an embodiment of the device mentioned above, wherein the device is designed to control at least the drum, the at least one electrical coil and the flooding unit.

Together with the flooding, a large contact area for heat transfer to the laundry can be provided by means of the drum as a heating element. As a result, heat can be transferred quickly to the laundry, so that the heating-up time can be kept short.

According to an embodiment not claimed, all of the drum walls of the drum can be formed from the ferromagnetic material. For example, the drum can be formed entirely of the ferromagnetic material. Such an embodiment offers the advantage that the drum can be heated uniformly and over a large area.

In particular, the at least one electrical coil can be formed flat and additionally or alternatively from copper. In this case, the at least one electrical coil can be operated with high-frequency electrical alternating voltage. Such an unclaimed Embodiment offers the advantage that a space-saving and efficient heating of the drum and thus the laundry is made possible.

Furthermore, the washing machine can have a tub, it being possible for the drum to be arranged inside the tub. In this case, the at least one electrical coil can be arranged on the tub. The tub can be drum-shaped. Such an embodiment, which is not claimed, offers the advantage that the at least one electrical coil can be positioned adjacent to the drum in a simple and defined manner.

In addition, the at least one electric coil can be arranged in the washing machine outside of a floor area arranged between the drum and a floor of the washing machine. More specifically, the at least one electric coil may be arranged at the top or side relative to the drum with respect to an orientation in an installed, set up or in-use state of the washing machine. Such an embodiment, which is not claimed, offers the advantage that a simple construction of the washing machine and uncomplicated access to the at least one coil can be implemented.

The automatic washing machine can also have at least one shielding element for shielding a magnetic field generated by the at least one electric coil in the direction away from the drum. Such an embodiment, which is not claimed, offers the advantage that propagation of the magnetic field outside the drum can be minimized or the magnetic field can be concentrated on the drum. The surrounding facilities of the washing machine can be protected from the magnetic field.

In this case, the at least one shielding element can have at least one ferrite plate and additionally or alternatively at least one aluminum plate. For example, magnetic fields that arise can be shielded by means of ferrite plates, with any remaining magnetic fields being additionally shielded by means of an aluminum plate, with ferrite plates being able to be arranged between the drum and the aluminum plate. Such an embodiment, which is not claimed, offers the advantage that reliable and effective magnetic shielding can be achieved.

Figur 1

eine schematische Darstellung eines Waschautomaten gemäß einem Ausführungsbeispiel der Erfindung;

Figur 2

eine schematische Darstellung eines Teilabschnittes eines Waschautomaten gemäß einem Ausführungsbeispiel der Erfindung;

Figur 3

eine schematische Darstellung eines Teilabschnittes eines Waschautomaten gemäß einem Ausführungsbeispiel der Erfindung;

Figur 4

ein Ablaufdiagramm eines Verfahrens zum Waschen gemäß einem Ausführungsbeispiel der Erfindung;

Figur 5

ein Ablaufdiagramm eines Verfahrens zum Betreiben gemäß einem Ausführungsbeispiel der Erfindung; und

Figur 6

ein Ablaufdiagramm eines Prozesses zum Waschen gemäß einem Ausführungsbeispiel der Erfindung.

An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows

figure 1

a schematic representation of a washing machine according to an embodiment of the invention;

figure 2

a schematic representation of a section of a washing machine according to an embodiment of the invention;

figure 3

a schematic representation of a section of a washing machine according to an embodiment of the invention;

figure 4

a flowchart of a method for washing according to an embodiment of the invention;

figure 5

a flowchart of a method for operating according to an embodiment of the invention; and

figure 6

a flowchart of a process for washing according to an embodiment of the invention.

figure 1 shows a schematic representation of a washing machine 100 for washing laundry according to an embodiment of the invention. The automatic washing machine 100 is designed here as a washing machine, a washer-dryer or the like. The washing machine 100 can also be referred to as a laundry treatment device or laundry care device.

The washing machine 100 has a drum 110 for receiving the laundry. The drum 110 is rotatably mounted in the automatic washing machine 100 . At least one wall or drum wall of the drum 110 is formed from a ferromagnetic material. Optionally, all of the drum walls of drum 110 are formed from the ferromagnetic material.

Furthermore, the automatic washing machine 100 has, for example, only one electric coil 120 . The electrical coil 120 is used to induce eddy currents in the at least one drum wall of the drum 110 . The drum 110 is heated by the eddy currents. The electrical coil 120 is arranged adjacent to the drum 110 so that an alternating magnetic field generated by the coil 120 acts on at least one section of the drum 110 .

According to the figure 1 The exemplary embodiment of the invention illustrated in the embodiment shown, the electric coil 120 is arranged outside of a floor area in the washing machine 100 which is arranged between the drum 110 and a floor of the washing machine 100 . According to one embodiment, the electrical coil 120 is shaped as a flat coil or planar. According to one embodiment, the electrical coil has 120 turns of copper. According to an exemplary embodiment, the automatic washing machine 100 can have a plurality of electrical coils 120 .

The washing machine 100 has according to in figure 1 shown exemplary embodiment of the invention also has a flooding unit 130 . The flooding unit 130 is designed to circulate wash suds through the drum 110 for flooding the laundry with wash suds. In this case, the circulation unit 130 is designed, for example, to circulate the wash suds intermittently through the drum 110 in order to keep the laundry in a damp state.

In addition, the washing machine 100 according to in figure 1 illustrated embodiment of the invention also has a tub 140 on. Inside the tub 140, the drum 110 is arranged. In this case, the electric coil 120 is arranged on the tub 140 , for example. A wall section of the tub 140 is arranged between the electric coil 120 and the drum 110 .

According to the figure 1 shown embodiment of the invention, the washing machine 100 also has only one shielding element 150 by way of example. The shielding element 150 is designed to shield or dampen a magnetic field or magnetic field generated by the electric coil 120 in the direction away from the drum 110 . The electrical coil 120 is arranged between the shielding element 150 and the drum 110 or the tub 140 .

The washing machine 100 also has an operating device 160 or device 160 for operating the washing machine 100 . The operating device 160 is, for example, a control unit or the like. According to the figure 1 In the exemplary embodiment of the invention shown, the shielding element 150 is arranged between the electric coil 120 and the operating device 160, so that components of the operating device 160 that are sensitive to magnetic fields can be protected by the shielding element 150 from the magnetic fields generated by the coil 120.

The operating device 160 has an application device 162 . The application device 162 is designed to apply an electrical signal 172 for inducing eddy currents in the at least one drum wall to heat the drum 110 to the electrical coil 120 . The electrical signal 172 can be a high-frequency alternating electrical voltage.

The operating device 160 has according to in figure 1 shown embodiment of the invention also has an output device 164. The output device 164 is designed to apply a flooding signal 174 to the flooding unit 130 in order to cause wash suds to be circulated through the drum for flooding the laundry with wash suds.

figure 2 shows a schematic representation of a section of a washing machine according to an embodiment of the invention. figure 2 shows the section of the washing machine in a schematic sectional view. The in figure 2 shown washing machine from the washing machine figure 1 . From the washing machine are in figure 2 Here, the drum 110, the electric coil 120 and the tub 140 are shown. Laundry 280 is also shown in the drum 110 by way of example.

The electrical coil 120 has according to in figure 2 shown embodiment of the invention has a curved sectional profile. A curvature of the electrical coil 120 follows a curvature of the drum 110 and the tub 140.

In other words, shows figure 2 a schematic diagram of induction heating for a washing machine. The electrical coil 120 is mounted on an upper side or on the side of the tub 140 in relation to an orientation in a mounted state or operating state. The drum 110 can be inductively heated by means of the electrical coil 120 .

figure 3 shows a schematic representation of a section of a washing machine according to an embodiment of the invention. while showing figure 3 the section of the washing machine in a sectional view. the inside figure 3 washing machine shown corresponds to or resembles the washing machine figure 1 . From the washing machine are in figure 3 here the electric coil 120 and the tub 140 are shown. The electrical coil 120 is arranged on the tub 140 .

figure 4 shows a flowchart of a method 400 for washing laundry according to an embodiment of the invention. The method 400 for washing is in connection with the automatic laundromat figure 1 , figure 2 or. figure 3 or a similar washing machine executable.

The method 400 for washing has a step 410 of inducing eddy currents in the at least one drum wall to heat the drum.

According to the figure 4 In the illustrated embodiment of the invention, the method 400 of washing also includes a step 420 of circulating wash suds through the drum to flood the laundry with wash suds. The circulating step 420 can be carried out before, during and/or after the inducing step 410 . The step 420 of circulating can also be carried out repeatedly.

In other words, step 410 of inducing and step 420 of circulating can be carried out, for example, parallel to one another and/or at different times and/or at least temporarily intermittently.

figure 5 shows a flowchart of a method 500 for operating according to an embodiment of the invention. The method 500 can be implemented to operate a washing machine. More specifically, the method 500 is executable to turn off the automatic laundromat figure 1 , figure 2 or. figure 3 or to operate a similar washing machine.

Thus, the method 500 of operating in conjunction with the automatic laundromat is over figure 1 , figure 2 or. figure 3 or a similar washing machine executable. In this case, the method 500 for operating by means of or using the operating device is off figure 1 or a similar operating device. In other words, the operating device is off figure 1 configured to perform method 500 of operating.

The method 500 for operating has a step 510 of applying an electrical signal to the electrical coil. The electrical signal applied causes eddy currents to be induced in the at least one drum wall by means of the electrical coil in order to heat the drum. The electrical signal is, for example, a high-frequency electrical AC voltage. Thus, in step 510 of application, the high-frequency electrical AC voltage is applied as an electrical signal, for example, in order to generate an alternating magnetic field with which the at least one drum wall of the drum is applied.

Additionally or alternatively, according to one exemplary embodiment, in step 510 of application, the electrical signal is pulse-width modulated depending on a load of laundry in the drum or a duty cycle or duty cycle of the electrical signal is modulated depending on the load.

According to an exemplary embodiment, the method 500 for operating also has a step 520 of outputting a flooding signal to a flooding unit. In step 520 of outputting, the flooding signal is output or made available for output to the flooding unit. The flood signal is adapted, when used by the flood unit, to cause wash suds to be circulated through the drum to flood the laundry with wash suds.

In this case, step 520 of dispensing can be carried out before, during and/or after step 510 of creating. The step 520 of outputting can also be carried out repeatedly. In other words, step 510 of applying and step 520 of outputting can be carried out, for example, in parallel with one another and/or at different times and/or at least temporarily intermittently.

figure 6 FIG. 6 shows a flow diagram of a process 600 for washing according to an embodiment of the invention. The process 600 for washing is off in connection with the washing machine figure 1 , figure 2 or. figure 3 or a similar washing machine executable. Also, the process 600 for washing associated with the method 400 for washing is off figure 4 and/or with the method 500 for operating figure 5 or similar procedures.

In a block 602, laundry is brought to a target saturation with wash suds or to a target amount of water. Subsequently, in a block 604, a flooding is started in order to bring residual water into the laundry. As a result, there is no longer any free liquor and the water or washing lye is completely or at least approximately completely absorbed in the batch of laundry.

In a block 606, an induction, in particular with a setting of a so-called booster operation, for example with an output of 2.5 kilowatts or the like, is started until a temperature rise of 10 Kelvin or a starting energy calculated as a function of the tied fleet is reached. The so-called booster operation can be selected to quickly get up to temperature.

Subsequently, in a block 608, the induction is adjusted in normal operation. The output can be set depending on the load so that the heating energy that is brought in can be optimally absorbed by the laundry. In normal operation, heating energy of, for example, 1.0 kilowatts can be introduced with a small load, heating energy of, for example, 1.5 kilowatts with a medium load, and heating energy of, for example, 2.0 kilowatts with a large load. A flow of heat can be increased by the flooding, and heat can also enter a core of the laundry.

Thereafter, in a block 612, circulation is carried out continuously until a target temperature Tsoll is reached. With a small load or load amount, the flooding can be carried out, for example, every 5 minutes, with a medium load, for example, every 2 minutes, and with a large load, for example, every 30 seconds. A rotational speed of the drum is hereby adapted to the circulation sequences or to the loading. If a current speed is greater than a circulation speed n _circulation , flooded. The circulation speed n _circulation can be in the range from 60 to 100 ^rpm , for example. Speeds of more than 60 ^rpm can expel lye, which can then be flooded or circulated to flood.

The induction mode is then switched off in a block 614 when the target temperature Tsoll has been reached. Thereafter, the process 600 proceeds to a decision block 616 where it is checked whether or not a post heat function is active. If the decision block 616 determines that the post heat function is active, the process 600 proceeds to a block 618 .

In block 618, the induction mode is switched over to a post-heating mode. In this case, a power level is set as a function of the target temperature Tsoll. The higher the setpoint temperature Tsoll, the higher the energy requirement. A power input can be between 0.3 kilowatts and 0.7 kilowatts, for example. In this case, the circulation can be carried out continuously, for example every minute, regardless of the load if a current speed is over 60 min ^-1 . An energy requirement for maintaining a temperature depends on the temperature level, with the load quantity or laundry load playing a subordinate role.

After that, in a block 622, a further program or sequence of a washing program is processed. If it is determined at decision block 616 that the post heat function is not active, then the process 600 transfers directly from decision block 616 to block 622.

In the following, with reference to the Figures 1 to 6 Backgrounds and advantages of exemplary embodiments of the invention are summarized again and/or briefly explained in other words.

An induction heating is implemented, in which the at least one drum wall or drum casing of the drum 110 can be heated or tempered by means of the electrical coil 120 .

As a result, heating energy can be supplied at an early stage even in an operating mode of the automatic washing machine 100 referred to as stepped refueling. The drum 110 is warmed up for the actual heating process. After the laundry 280 is sufficiently damp, the actual heating process begins.

The laundry 280 is, for example, in a normal washing cycle, z. B. a ramp rhythm or the like rotated. In phases, the wash 280 optionally becomes short thrown at. Such an expulsion of lye activates a pressure-dependent flooding. The heat from the drum wall or the drum casing is transferred to the suds and is brought directly into the laundry 280 by the introduction of the washing suds by means of circulation.

This process can be carried out depending on the load. The larger a batch or batch of laundry, the more often the suds can be expelled by spinning or the like. Furthermore, a speed of the drum 110 can be set to be increased. In the case of small batches of laundry, there is no need to spin the laundry completely because there is sufficient contact between the laundry 280 and the drum 110 even with normal washing rhythms.

Thus, in the case of a large batch of laundry or a large load of laundry 280, the circulation can be activated, for example, once a minute or the like. In the case of a medium batch of laundry, the circulation can be activated every two minutes or the like, for example. With a small batch of laundry, the flooding can optionally be omitted.

A permanent direct contact of the drum 110 with the items to be washed or the laundry 280 is given at a drum speed equal to or higher than the so-called contact speed.

By processing the heating process in this way, it is possible, for example, to at least partially avoid switching on and off until a desired selection temperature or a desired heating energy is reached.

Furthermore, a power output targeted for the process step can be set by means of the electrical signal 172 through a regulated power output of the induction heating, similar to a hob. The output can be set in such a way that the laundry 280 can absorb the heating energy that has been introduced. A load of laundry 280 can also be taken into account.

In a normal heating process, a heating output of, for example, 1.2 kilowatts can be introduced with a small load, a heating output of, for example, 1.8 kilowatts with a medium load, and a heating output of, for example, 2.1 kilowatts with a large load. A heating output of 1.0 kilowatts, for example, can be introduced for post-heating, and a heating output of 3.0 kilowatts, for example, can be introduced for rapid heating (booster).

A washing drum 110 or drum 110 with a drum wall made of ferromagnetic material is used for such an induction heating. A flat copper coil 120 that can be operated, for example, with high-frequency alternating voltage is attached outside the drum wall. This generates an alternating magnetic field, which generates eddy currents in the drum wall. The drum wall heats up due to Joule losses. In this way, the entire drum is heated by the induction heating.

For example, the resulting magnetic fields can be shielded using ferrite plates. The remaining magnetic fields can additionally be shielded by an aluminum plate adjacent to the ferrite plates. In this case, the ferrite plates can be arranged between the aluminum plate and the electric coil 120 . Thus, the ferrite plates and the aluminum plate represent shielding elements 150 of the washing machine 100.

With induction heating, there is no longer any need for free liquor to start a heating process. Since no free liquor is required for the heating, the water consumption of the automatic washing machine 100 can also be reduced. The consequence of this is that a detergent concentration in the water can also be increased and additionally or alternatively the addition of detergent can be reduced. Even with very small loads, no free liquor needs to be heated and unwanted heating of surrounding components of the automatic washing machine 100 can also be minimized. Furthermore, heating can be started at an early stage, which can have a positive effect on the washing effect.

In a washing method with active circulation, in which the laundry 280 is at least temporarily only brought into a damp state, heating can be made possible before, during and/or after the respective water supply processes, a so-called graduated refueling. In this way, warming can already be achieved with a staged refueling. Furthermore, for example, a cumbersome heating process by means of steam can be avoided. In addition, however, a steam smoothing function can be implemented quickly and reliably.

Claims (3)

1. Method (500) for operating a washing machine (100), the washing machine (100) having a drum (110) for receiving laundry (280) and a flooding unit (130), the method (500) comprising at least the following step of:

   outputting (520) a flooding signal (174) to the flooding unit (130) in order to circulate washing suds expelled from the laundry (280) through the drum (110) to flood the laundry (280) with washing suds in order to saturate the laundry (280) with washing suds,

   the drum (110) having at least one drum wall made of a ferromagnetic material and at least one electrical coil (120) arranged adjacent to the drum (110), and in that the method also comprises the step of:

   applying (510) an electrical signal (172) to the at least one electrical coil (120), in order to induce eddy currents in the at least one drum wall, in order to heat the drum (110),

   characterised in that,

   in the application step (510), an electrical signal (172) is applied, which is suitable for generating a heat output which is dependent on a load quantity of laundry (280) in the drum (110) and on a temperature of the drum (110).
2. Method (500) according to claim 1, wherein the outputting step (520) is carried out repeatedly before, during and/or after the application step (510).
3. Device (160) for controlling a washing machine, which is designed to carry out the steps of the method (500) according to either claim 1 or claim 2.

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