DE102010029075A1 - Laundry treatment apparatus and method for operating a laundry treatment appliance - Google Patents

Abstract

The laundry treatment device (1) is equipped with at least one heating device (3, 7), the at least one heating device (3, 7) having at least one magnetic material (4) with a predetermined Curie temperature (Tc) and at least one alternating field generating means (7) for generating of an alternating magnetic field (F) at the location of the at least one magnetic material (4). The method is used to operate a laundry treatment device (1), a magnetic material (4) being irradiated by means of an alternating magnetic field (F), so that the magnetic material (4) is heated and its heat loss is at least partially transferred to a process medium (M) to be heated. is transmitted, and / or a magnetic material (24) switches a switch (23) when its Curie temperature (Tc) is reached, which in turn switches at least one heating means (28) of the laundry treatment device (1).

Description

The invention relates to a laundry treatment appliance, in particular a washing machine, tumble dryer or washer-dryer, with at least one heating device and a method for operating a laundry treatment appliance.

Previously known resistance heaters in laundry treatment appliances have, among other things, the following characteristics: The pipe heaters typically used in washing machines for heating wash liquor overheat if they are not in contact with the wash liquor. In order to avoid this overheating and resulting accidents (eg fires), temperature-limiting elements (eg fuses) must be installed. Failed or blown fuses are always a service case. Furthermore, the control of the heating elements must be operated externally. The necessary control electronics cause material costs. The heating elements of the resistance heaters are also discrete components and must be laboriously mounted and tested. You also need a relatively large amount of space.

The associated work steps are associated with costs. There is a risk of assembly errors, which can lead to rework or service costs. In addition, settle on the heating elements over time deposits, eg. As lime or fluff from. These deposits can cause problems over time, such as inferior energy transfer, chipped fragments of deposits, etc. Furthermore, the inclusion of the heater requires a pocket in the tool. The realization of this bag causes not inconsiderable tool costs.

EP 0 418 807 A2 describes magnetic dispersions of ferrite particles with a high magnetic energy product in a flexible highly saturated nitrile rubber and method of making the same. To this end, a flexible magnetic blend composition is provided which consists of high energy magnetic ferrite particles in a flexible, highly temperature resistant and oil resistant polymer binder. The system binder is highly charged, usually 55 to 65 volume percent, charged with the ferrite particles, ie, barium and / or strontium ferrite particles, which have bonded magnets with a maximum energy product of at least 1.0 Mega Gauss oersted, a remanence Br of at least 2000 gauss, a coercive force H0 of at least 1800 oersted and an intrinsic coercive force Hci of at least 2000 oersted. The process for making this system involves mixing the binder system and the ferrite particles, with the ferrite particles being oriented in a preferred direction during processing and then brought to a final geometry before being cured by high voltage electron beam radiation, preferably with over 3 MeV. Solid state electron beam hardening fixes the dimensional stability, magnetic properties, oil, solvent and chemical resistance of the part even when subsequently exposed to unfavorable temperature environments of 125 ° C or more. Any misfolded parts or cuttings that occur in the process prior to radiation curing can be recycled through repeated processing without the risk of premature curing.

US 5,329,085 describes a Curie point heater, primarily for use in a soldering iron and originally designed to operate with currents in the megahertz range, which is redesigned to operate in the kilohertz range. Further, in one embodiment of the heater, the coil that excites the heater is mounted in the handle of the piston.

US 5,182,427 describes a self-regulating heater provided by placing a ferrite body member, which is highly lossy when exposed to a high-frequency magnetic field, and a predetermined Curie temperature, on or around a center conductor connected to or configured with a power source to be connected, which provides the conductor with a high frequency alternating current is provided. The current flowing through the center conductor creates a magnetic field around the conductor which causes the ferrite body to heat up to its Curie temperature due to internal losses. The heater regulates itself at the Curie temperature of the ferrite body itself. The power source is preferably an impedance-matched, constant current power source. The ferrite body element may be ferromagnetic or ferrimagnetic. The ferrite body is preferably ferrite magnetic, such as ferrite beads, rings and the like, which heat up by hysteresis losses.

US 4,303,196 describes a temperature-sensitive valve in which the annular valve seat is made of a thermally sensitive magnetic material having a Curie temperature having a predetermined value. A vertically movable valve plug is positioned below the valve seat and includes a permanent magnet which normally forces the plug up into the valve seat to close the valve, but which allows the valve to open when the temperature of the valve seat is at the Curie temperature exceeds.

US 4,414,519 describes a temperature-sensitive relay equipped with a compliant movable cantilever made of an amorphous ferromagnetic material having a Curie point. The boom is adapted to carry a first contact element. A second contact element is arranged adjacent to the first contact element for at least periodically establishing an electrical contact with the first contact element. The relay is adapted to be connected to a circuit having a power source for providing an electrical current and a switching mechanism for activating the circuit in response to a preselected state. A magnet is arranged and adapted to bias the cantilever to a first position which interrupts electrical continuity between the first and second contact elements. The cantilever is converted from a ferromagnetic phase to a paramagnetic phase when its temperature exceeds the Curie point, whereby the cantilever assumes a second position in which electrical continuity is established. A heating means is connected to the circuit and arranged in the vicinity of the boom for heating the boom to effect the transfer during a preselected period of time following the activation of the circuit.

It is the object of the present invention to at least partially overcome or mitigate the disadvantages of the prior art, and more particularly to provide heating capability in laundry treating appliances which is low maintenance, easy to assemble, compact, reliable and easy to use.

This object is achieved according to the features of the independent claims. Preferred embodiments are in particular the dependent claims.

The object is achieved by a laundry treatment device having at least one heating device, wherein the at least one heating device comprises at least one magnetic (ie, ferromagnetic or ferrimagnetic) material or material volume having a predetermined Curie temperature (Tc) and at least one alternating field generating means for generating an alternating magnetic field at the location of the has at least one (ferro- or ferri-) magnetic material.

Ferromagnets and ferrimagnets are characterized by the so-called Curie temperature. Below this temperature ferromagnets absorb alternating magnetic fields, above this temperature they are inactive for the alternating fields. The absorption of alternating magnetic fields leads to heat generation. This property is particularly pronounced in hard magnetic materials. In technical application, this means that the magnetic material converts the energy of the alternating magnetic field into heat until the Curie temperature is reached. It follows that when applying a (sufficiently strong) alternating electromagnetic field, the ferromagnetic or ferrimagnetic (heating) material is kept at the Curie temperature Tc. The heat generated by the magnetic material can be delivered ("magnetic heating") to a process medium to be heated of the laundry treatment appliance (eg, liquor, fresh water and / or process air). Ferromagnetic or ferrimagnetic materials are commercially available for a wide range of Curie temperatures Tc.

Such a laundry treatment appliance has, inter alia, the following advantages: it is possible to dispense with a temperature-limiting technique. The heater is rather intrinsically safe, because a predetermined set temperature (which correspond to the Curie temperature or, taking into account heat losses, may be less than the Curie temperature Tc) is not exceeded. Damage even at temperatures around 100 ° C does not lead to destructive damage, such as spontaneous combustion, burning through or scaling. The magnetic material can also be integrated directly into components or structures of the laundry treatment appliance, for. B. in a pipe or a tub. This eliminates the need for discrete heating elements, so that a cost of assembly, sealing and wiring is eliminated, as well as related possible assembly errors. This integration also eliminates the space previously required for the separate heating elements, while the alternating field generating means (eg, a coil coupled to a frequency generator) can be designed to be much more compact, so that the laundry treatment appliance can be designed to be particularly compact and flexible in terms of design. In addition, tools for making the components of the laundry treatment device may be simpler. In addition, linting and / or calcification can at least be reduced. Also, because of a potentially lower operating temperature of the 'magnetic heater', for example due to better contact with the process medium, more favorable energy efficiency may be achieved. In addition, the bag can now be optimized in the tool, z. B. on a derivative of a resulting during a spinning liquid. The bag would generally simplify and reduce costs.

It is an embodiment that the laundry treatment appliance has exactly one heating device, for. B. with a field generating agent and one or more of them magnetically irradiated material volumes of the magnetic material. Alternatively, the laundry treating appliance may have a plurality of such heaters whose magnetic material has a different Curie temperature Tc. Thus, the process medium can be heated to different set temperatures. These multiple heaters can be activated individually, for example, depending on a desired setpoint temperature, z. B. by means of a laundry treatment program. The multiple heaters can also be activated in individual groups together.

It is a further embodiment that the laundry treatment device has a washing function and the magnetic material is integrated into a tub. The laundry treatment device can, for. B. be a washing machine or a tumble dryer. The integration into the tub can be dispensed with the space for the previously used separate resistance heating. The alternating field generator, z. As a coil, can be attached directly to the magnetic material-containing component, here: the tub. The tub can z. B. have a plastic surface which shields the magnetic material against the alkali, so that the magnetic material does not corrode. The tub can, for example, at the points that come into contact with the liquor, be made of plastic, in which the (ferromagnetic or ferri-) magnetic material (eg., Via a masterbatch) is fed. Can be made such a tub z. B. by means of a two-shot injection molding process.

It is yet another embodiment that the (ferro-) or ferri-) magnetic material is present as part of a paint and is applied in particular at the points where a heat input is intended.

It is still an embodiment that the magnetic material is integrated into a channel for process medium. As a result, heating of the medium flowing through the channel can be carried out in a particularly compact manner. A channel guide can be designed to be flexible. The channel may be formed at its portion surrounding the magnetic material (i.e., the ferromagnetic or ferrimagnetic material having the predetermined and selected Curie temperature Tc), e.g. B. surrounded by a coil or winding or more straight, have the magnetic material traversing conductor. The tube can z. B. be a plastic tube, in which the magnetic material is fed, z. For example via a masterbatch. The (ferro- / ferri-) magnetic pipe section can, for. B. act as a water heater or be such.

It is a preferred development for effective heat transfer that the channel has an internal structure comprising the magnetic material. Thus, a heat transfer area between the magnetic material and the process medium can be increased. Due to the integral construction of the magnetic material, the inner structure can be designed to be particularly complex and large-area.

It is preferred for a particularly effective heat transfer development that the channel has at least one portion whose flow cross-section for the medium has a plurality of sub-channels whose walls have the magnetic material. Thus, over a short distance in a compact manner, a particularly high amount of heat can be introduced into the process medium flowing through. The number and the flow cross section of the sub-channels can be z. B. depending on the process medium (air, liquid (fresh water, lye)), the amount of heat to be transmitted and / or the volumes to be heated can be adjusted.

It is manufacturing technology advantageous if the sub-channels have a honeycomb structure in cross-section. By this geometry, a very large thermal contact surface for a given flow cross-section can be obtained.

It is yet another embodiment that the laundry treatment appliance has a laundry drying function (eg a tumble dryer or a washer-dryer) and the process medium is air.

It is also an embodiment that the laundry treatment appliance has a washing function (eg a washing machine or a washer-dryer) and the process medium is (wash) liquor.

It is a development that the magnetic material has ferrite. Ferrites are cost-effective "bulk chemicals" and can also be customized to specifications (eg Curie temperature and / or other magnetic parameters). For example, ferrites in a "masterbatch", z. B. as in EP 0418 807 A2 described, are produced. Such masterbatches can be processed by injection molding. A ferrite exhibiting component of the laundry treatment appliance can be made very inexpensive, z. B. by means of a varnish, by means of two-component injection molding or by means of a "two-shot technique" are injected into the component, especially where the application of Heat is intended. This is especially the case if the shell of the component itself is injection-moldable.

It is still a development that the magnetic material comprises a NiFe alloy. NiFe alloys are inexpensive and available for various suitable Curie temperatures and can be processed in the major mass production processes.

However, the invention is not limited to ferrites or NiFs, but may include any magnetic material having a Curie temperature.

Using an injection molding technique to form the magnetic (ferromagnetic or ferrimagnetic) material can have the following advantages: the magnetic material is very complex moldable. The magnetic material as the heat source can be integrated directly where the heat is to be introduced into the process medium, which mates a compact design with high design flexibility and enables effective heat transfer. Furthermore, a large heat contact surface can be realized, so that the process medium can be heated more quickly, which allows a faster temperature control of the process medium. However, other manufacturing methods are possible, for. B. by an integration of films, sheets, rods, moldings, etc. or use of a sintering process. Such components can be used by encapsulation technique or simply as inserted, glued, clamped and / or latched items.

It is also a development that the magnetic material is surrounded by an electrically insulating protective sheath, in particular plastic sheath. As a result, the magnetic material can be irradiated without shielding the alternating magnetic field while at the same time providing a protective sheath or protective layer which protects against chemical and abrasive degradation. Also, the plastic jacket is good to produce together with the magnetic material, for. B. by a two-component injection molding process or use of masterbatches. The application of heat to the place where it is needed can be made possible in particular by the two-shot process, wherein the magnetic substance is preferably introduced only where heat is intended later. However, other manufacturing methods are possible, for. B. making a core of the magnetic material, for. Example by means of injection molding or sintering, and subsequent coating, for. B. by spraying, injection molding, painting, etc.

It is yet another embodiment that the alternating field generating means comprises at least one antenna which is electrically connected to a frequency generator. The frequency generator can feed the antenna with an alternating current, which then emits the magnetic alternating field with at least substantially the same frequency. The antenna may for example be a coil, the z. B. is arranged outside of the magnetic material. The antenna may alternatively z. B. be a straight, guided by the magnetic material conductor. The frequency generator can be an AC voltage z. In a range of kHz or MHz.

In an alternative embodiment, the antenna (without using a frequency generator) can be applied directly to a, possibly reduced amplitude, mains voltage signal.

The object is also achieved by a laundry treatment device having at least one heating device, in particular as described above, wherein the laundry treatment device has at least one Curie switch, which has a magnetic (ferromagnetic or ferrimagnetic) material having a predetermined Curie temperature, so that the Curie switch at or after reaching the Curie temperature of the magnetic material, wherein the magnetic material is in thermal communication with a process medium of the laundry treating appliance. The Curie switch eliminates the need for a combination of temperature sensor and control. In other words, the Curie switch can simultaneously act as a sensor and as a controller or as a switching sensor. The Curie switch switches very precisely and with only small tolerances (eg in contrast to a bimetallic switch).

It may be advantageous for a setting of one of several temperature levels, in particular a wash liquor, that the laundry treatment device has a plurality of switches with different Curie temperatures, wherein the Curie temperatures is in the range of a possible target temperature of the process medium. It is also an embodiment that the Curie switch switches an associated heater for heating the process medium. The heaters can be activated individually as a function of the target temperature to be reached or be switched on or off individually depending on the applied current temperature by the associated Curie switch. This allows an intrinsically safe heating can be achieved, which can be dispensed with a complex temperature sensing and control.

It is a special embodiment that these switches or switching devices are used specifically for a temperature control of selected washing programs.

It is an embodiment that the ferromagnetic or ferrimagnetic material is at least partially surrounded by the process medium to achieve a rapid response to a temperature change.

It is still an embodiment that the (ferro- or ferri-) magnetic material is surrounded by an at least electrically insulating protective jacket, in particular made of plastic. As a result, the magnetic material can be magnetically irradiated without shielding the alternating magnetic field while at the same time providing a protective sheath or protective layer which protects against chemical and abrasive degradation. Also, the plastic jacket is good to produce together with the magnetic material, for. B. by a two-component injection molding process or two-shot process.

The Curie switch can z. B. be a valve or a relay.

It is still an embodiment to use at least one ferromagnetic or ferrimagnetic component, which is in contact with the medium to be heated, as a temperature sensor. The change in magnetizability occurring at the Curie temperature may detune a resonant circuit mounted near but out of the medium. The signal generated from the detuning can be used, for example, to switch a heater.

It is also an embodiment to use a standing with the medium to be heated in thermal contact ferromagnetic or ferrimagnetic substance as a switching plunger of a relay or solenoid valve. For example, supply flows from heaters or a flow of wash liquor, fresh water or dryer air can be controlled.

The object is also achieved by a method for operating a laundry treatment appliance, wherein a ferromagnetic or ferrimagnetic material is irradiated by means of an alternating magnetic field, so that the ferromagnetic or ferrimagnetic material is heated and its heat loss is at least partially transmitted to a process medium to be heated, and / or a ferromagnetic or ferrimagnetic material turns on reaching its Curie temperature a switch which in turn switches at least one heating means of the laundry treating appliance. This also results in the already discussed above advantages and possible embodiments.

In general, the invention thus comprises the use of a material having a predetermined Curie temperature Tc in a laundry treatment appliance, namely for intrinsically safe switching off of heating means and / or for exact and simple temperature control when the Curie temperature Tc is reached.

In the following figures, the invention will be described schematically with reference to exemplary embodiments. In this case, the same or equivalent elements may be provided with the same reference numerals for clarity.

1 shows a sectional view in an oblique view of a component of a laundry treatment device in the form of a channel section for a process medium with a magnetic material;

2 shows a sectional side view of another component of a laundry treatment device in the form of a tub with a further magnetic material; and

3 shows a sectional side view still another component of a laundry treatment device in the form of a tub with a Curie switch.

1 shows a component of a laundry treatment device 1 in the form of a channel section 2 for passing a process medium M. The channel section 2 has a tubular outer wall 3 which is a ferromagnetic material here 4 having, on both sides of a plastic material 5 is sheathed. The flow cross section of the channel section 2 is in several subchannels 6 divided, which are parallel to the longitudinal direction of the pipe section 2 and have a profile in the profile (perpendicular to the longitudinal axis L) is substantially honeycomb-shaped structure with hexagonal wall shapes. Also the walls of the subchannels 6 are surrounded by a plastic lined with a magnetic material (ie, a ferromagnetic or ferrimagnetic material). On its outside is the pipe section 2 from a coil 7 with several windings 8th surround.

During operation of the channel section 2 gets through the coil 7 , which is connected to a frequency generator (not shown), an alternating electric field F at the location of the magnetic material 4 generated because of the plastic sheath 5 is substantially permeable to the alternating magnetic field F. By means of the alternating magnetic field becomes the magnetic material 4 heated up until it reaches its Curie temperature Tc. With Reaching the Curie temperature Tc is the magnetic material 4 for the alternating magnetic field F no longer receptive and thus not further heated. By the operation of the coil 7 can thus be the magnetic material 4 be set exactly to the Curie temperature Tc, without a risk of overheating. The Curie temperature Tc can be accurately specified by an appropriate choice of materials. The heat W generated by the irradiation of the alternating magnetic field F in the magnetic material 4 is at least partly on the plastic shell 5 and further transferred to the process medium M. To avoid heat loss to other than the process medium M, the channel section 2 be surrounded on its outside with a thermally insulating material.

The channel section 2 thus represents a continuous flow heater for the process medium M flowing through. The process medium M can be air or a liquid (for example water or lye). This channel section 2 has the advantage over a continuous flow heater with a conventional resistance heating, that can be dispensed with large-volume resistance heating. The turns 8th the coil 7 take up comparatively little space. It is also possible to have comparatively fine structures, such as the subchannels 6 , to set up a large area for heat dissipation. As a result, a particularly effective and compact possibility for heating the process medium M can be provided. In addition, the pipe section can be 2 comparatively easy to produce, for example in the context of a single manufacturing process, for. B. by a two-component injection molding or two-shot process.

The channel section 2 For example, it can be introduced into a process air duct of a laundry drying device and can heat there, for example, air to be injected into a treatment chamber of the laundry drying device. Alternatively, the channel section 2 be used for example for heating liquor in a laundry treatment device with a washing function. Another application for a laundry treatment appliance is the heating of supplied fresh water.

Alternatively, the pipe section 2 also be a (ferro- or ferri-) magnetic tube without the plastic coating, in particular if the process medium M is a dry gas or the magnetic material 4 is insensitive to corrosion by the process medium M.

2 shows another component of a laundry treatment device 11 in the form of a tub 12 , which is similar to the pipe section 2 one from a plastic 5 sheathed core of a magnetic (ferromagnetic or ferrimagnetic) material 4 having. The tub 12 takes lye L, in which a lower part of a laundry drum (not shown) rotates. The liquor L is typically heated for cleaning, conventionally resisting heating elements on the tub 12 are attached or in a occupied by the liquor L space between the tub 12 and the laundry drum.

In the embodiment shown, however, the tub is 12 itself heated by an externally mounted coil 13 preferably with several turns 14 circular around a region which is also wetted by the liquor L, the bottom of the tub 12 is wrapped around. As a result, first heat W can be discharged into the liquor L very effectively, with the liquor container being for this purpose 12 may be provided on its outside with a heat-insulating material. Furthermore, a gap between the tub 12 and the laundry drum are kept particularly small, whereby an amount of liquor L required for a wash cycle can be reduced. The reduction in liquor L in turn reduces water consumption and energy consumption. In addition, it does not take so much detergent in the liquor L for effective cleaning of the laundry.

When operating the washing machine 11 is similar to the pipe section 2 out 1 , through the coil 13 generates an alternating magnetic field F, which is the magnetic material 4 heated, which in turn the liquor L can be heated. It may be sufficient if the tub 12 only up to a maximum level of the liquor L, the magnetic material 4 having the predetermined Curie temperature Tc, or the magnetic material 4 even an even smaller area at a lower area of the tub 12 occupies.

3 shows a section of a washing machine 21 with a tub 22 , wherein the tub 22 a conventional tub or in 2 shown magnetically heated tubs 12 can be. The tub 22 has a sensor or Curie switch switching at a predetermined Curie temperature Tc 23 on, which is carried out here physically in two parts. This is the Curie switch 23 from a volume of (ferro- or ferri-) magnetic material 24 , which on an inside of the tub 22 is disposed at a position which is typically covered by the liquor L, here: at the lowest point of the tub 22 , To prevent corrosion by the liquor L is the magnetic material 24 surrounded by a plastic sheath.

On the dry outside of the tub 22 and the magnetic material 24 opposite or through the tub 22 separated is a second part of the Curie switch 23 with a coil 25 and an evaluation circuit 26 , About the coil 25 is through the tub 22 through, which at least at this point for that of the coil 25 generated magnetic alternating field is permeable, at the location of the magnetic material 24 generates the alternating magnetic field, wherein an associated field strength is not so high that they cause significant heating of the magnetic material 24 entails.

The magnetic material 24 changes its magnetic property when the liquor L has a predetermined Curie temperature Tc of the magnetic material 24 reached. When the Curie temperature Tc is reached, the "magnetic environment" of the coil thus changes 25 , what by means of the evaluation logic 26 is detectable. For example, by reaching the Curie temperature Tc in the Auswertelogik 26 existing or coupled thereto resonant circuit be detuned, which is sensed with high accuracy. Such sensors are available as integrated circuits and very cost effective. The evaluation logic 26 can then one through the Curie switch 23 switchable heating 28 to warm the liquor L off. For this purpose, for example, an output signal of the evaluation logic 26 be used as a release for a relay or a TRIAC, over which in turn a heating current is switchable. The heating system 28 may be a conventional heater or a 'magnetic heater', in particular as described above.

This Curie switch 23 which is also operable only as a Curie sensor, can reliably detect reaching the Curie temperature Tc from a lower temperature or from a higher temperature. Decreases, for example, by switching off the heating 28 the temperature of the liquor L again becomes the magnetic material 24 Upon reaching the Curie temperature Tc from a higher temperature again absorbing for the alternating magnetic field F, whereby the resonant circuit of Auswertelogik 26 is retuned. Then the Curie switch 23 the heating system 28 turn on again.

Alternatively to the Curie switch shown 23 Other Curie switches (valves, relays, etc.) or Curie sensors can also be used, for example US 4,303,196 and US 4,414,519 known. In this case, the part in contact with the process medium M is preferably of a protective jacket 27 surrounded, in particular, if the process medium M is a corrosive medium. A Curie switch 23 has, for example, the advantage over a bimetal element that it switches very precisely with the Curie temperature and, for example, is also insensitive to thermal cycling. When using a relay or solenoid valve as the Curie switch z. B. a plunger of the relay or the solenoid valve are in direct contact with the liquor L, via a protective sheath or seal.

Of course, the present invention is not limited to the embodiments shown.

LIST OF REFERENCE NUMBERS

1

Laundry treatment device

2

channel section

3

outer wall

4

ferromagnetic material

5

Plastic sheath

6

subchannel

7

Kitchen sink

8th

winding

11

Laundry treatment device

12

tub

13

Kitchen sink

14

convolution

21

Washing machine

22

tub

23

Curie switch

24

magnetic material

25

Kitchen sink

26

evaluation logic

27

mantle

28

heater

L

lye

F

alternating electrical field

M

process medium

S

longitudinal axis

tc

Curie temperature

W

warmth

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0418807 A2 [0004, 0023]
• US 5329085 [0005]
• US 5182427 [0006]
• US 4,303,196 [0007, 0056]
• US 4414519 [0008, 0056]

Claims (15)

Laundry treatment appliance ( 1 ; 11 ) with at least one heating device ( 3 . 7 ; 12 . 13 ), wherein the at least one heating device ( 3 . 7 ; 12 . 13 ) at least one magnetic material ( 4 ) having a predetermined Curie temperature (Tc) and at least one alternating field generating means ( 7 ; 13 ) for generating an alternating magnetic field (F) at the location of the at least one magnetic material ( 4 ) having. Laundry treatment appliance ( 11 ) according to claim 1, wherein the laundry treatment appliance ( 11 ) has a washing function and the magnetic material ( 4 ) in a tub ( 12 ) is integrated. Laundry treatment appliance ( 1 ) according to any one of the preceding claims, wherein the magnetic material ( 4 ) into a channel ( 2 ) is integrated for the process medium (M). Laundry treatment appliance ( 1 ) according to claim 3, wherein the channel ( 2 ) has at least one section whose flow cross section for the process medium (M) has a plurality of subchannels ( 6 ) whose walls are the magnetic material ( 4 ) exhibit. Laundry treatment appliance ( 1 ) according to claim 4, wherein the subchannels ( 6 ) have a honeycomb structure in cross-section. Laundry treatment appliance ( 1 ) according to one of claims 3 to 5, wherein the laundry treatment appliance ( 1 ) has a laundry drying function and the process medium (M) is air. Laundry treatment appliance ( 1 ) according to one of claims 2 to 6, wherein the laundry treatment appliance ( 1 ) has a washing function and the process medium (M) is alkali. Laundry treatment appliance ( 1 ; 11 ) according to any one of the preceding claims, wherein the magnetic material ( 4 ) Has ferrite. Laundry treatment appliance ( 1 ; 11 ) according to any one of the preceding claims, wherein the magnetic material ( 4 ) comprises a NiFe alloy. Laundry treatment appliance ( 1 ; 11 ) according to any one of the preceding claims, wherein the magnetic material ( 4 ) of an electrically insulating protective jacket ( 5 ), in particular plastic sheath, is surrounded. Laundry treatment appliance ( 1 ; 11 ; 21 ) with at least one heating device ( 28 ), in particular according to one of the preceding claims, wherein the laundry treatment appliance ( 21 ) at least one Curie switch ( 23 ) comprising a magnetic material ( 24 ) with a predetermined Curie temperature (Tc), so that the Curie switch ( 23 ) at or after reaching the Curie temperature (Tc), the magnetic material ( 24 ) with a process medium (M, L) of the laundry treatment appliance ( 21 ) is in a thermal connection. Laundry treatment appliance ( 21 ) according to claim 11, wherein the magnetic material ( 24 ) is at least partially surrounded by the process medium (M, L). Laundry treatment appliance ( 21 ) according to claim 12, wherein the magnetic material ( 24 ) of an at least electrically insulating protective jacket ( 27 ), in particular of plastic, is surrounded. Laundry treating appliance according to one of claims 11 to 13, wherein the Curie switch ( 23 ) a heater ( 28 ) for heating the process medium (M). Method for operating a laundry treatment appliance ( 1 ; 11 ; 21 ), wherein - a magnetic material ( 4 ) is irradiated by means of an alternating magnetic field (F), so that the magnetic material ( 4 ) is heated and its heat (W) is at least partially transferred to a process medium to be heated (M), and / or - a magnetic material ( 24 ) upon reaching its Curie temperature (Tc) a switch ( 23 ), which in turn at least one heating means ( 28 ) of the laundry treatment appliance ( 21 ) switches.

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