EP2010705B1 - Machine for washing and/or drying laundry - Google Patents

Abstract

A machine for laundry has a drum shaft rotatably mounted by a bearing for driving a laundry drum and having a device for determining loading-relevant characteristic variables or an unbalance of the laundry drum or of the drum shaft. The device for determining loading-relevant characteristic variables or an unbalance includes a magnetic field sensor that senses a magnetized region on the drum shaft or the laundry drum.

Description

The invention relates to a machine for washing and / or drying of laundry, in particular according to the front loader principle, and a method for determining and processing load-related characteristics or unbalance parameters of a laundry drum or a drum shaft of the machine in the preambles of claims 1 and 10 specified type.

A problem in the operation of washing machines are the vibrations occurring in particular during the spin phase. This is caused by the unbalanced mass distribution of the laundry in the laundry drum resulting imbalance. This unbalance can already be present from the beginning of the washing process on, but it can also be formed only during a spin operation by different drainage properties of the laundry and change in the course of time. By appropriate suspension of the washing unit with the washing drum occurring unbalance forces are taken into account. When a large imbalance occurs at high speeds, it may still be excessive demand of the suspension of the washing unit, which can lead to a so-called running or hitting the machine. But even when operating the machine within tolerable vibration deflections cause the unbalanced forces not only to unwanted noise, but also to increased wear of the washing machine, especially the moving parts and bearings. The aim of an optimized washing process control must therefore be the most comprehensive possible determination of load-relevant parameters or unbalance parameters and their evaluation to effectively limit and / or completely avoid the imbalance caused by the mass distribution of the laundry.

From the DE 100 22 609 C2 is a method for limiting the imbalance of a washing unit of a washing machine and an apparatus for performing the method to be taken as known. In this case, several sensors are distributed to determine a occurring during the washing process by a moving laundry drum imbalance on the circumference of a tub of the washing machine. These sensors detect the unbalance-induced deflections of the tub as well as the phase shifts between the unbalance deflections. Depending on the detected Deflection values are introduced measures to limit the imbalance. In this case, acceleration sensors, optical and / or electromechanical displacement sensors can be used as sensors.

A disadvantage of this method and this device is the fact that only the unbalance generated by the unbalanced loadings of the laundry dynamic, already acting imbalance is detected by the arranged on the tub sensors and also not all relevant for an effective limitation of this imbalance parameters, such as the total weight of the washing laundry located in the washing drum, are detectable. Furthermore, it is to be regarded as a disadvantage that on the one hand by the need for multiple sensors for carrying out the method increased production costs incurred, on the other hand their attachment to the outer circumference of the tub to constructive limitations of the also arranged in this area components leads.

A washing machine and a sensor arrangement for determining a laundry imbalance is also off EP 856 604 A2 known, wherein for detecting the position of the imbalance, a magnetic sensor unit, namely a Hall sensor, is used. Another measuring device of a washing machine is in WO 2005/059492 A1 disclosed. This measuring device comprises a magnetic field sensor unit for determining rotational parameters.

Object of the present invention is therefore to provide a machine and a method of the type mentioned, by means of which a larger number of relevant parameters for a more efficient limitation of imbalance effects is accessible and by a more compact, flexible and cost-saving design of the machine is possible ,

The object is achieved by a machine for washing and / or drying laundry and a method for determining and processing load-related characteristics or unbalance parameters of a laundry drum or a drum shaft of the machine with the features of claims 1 and 10, respectively.

Advantageous embodiments with expedient and non-trivial developments of the invention are described in the remaining claims.

The machine according to the invention is in particular a washing machine according to the front loader principle, meaning a washing machine with a laundry drum rotatably mounted about a horizontal axis or a slightly inclined axis relative to a horizontal axis, which can be filled with laundry from the front. However, it would also be conceivable tumble dryer or any other machinery for the treatment of garments, where there is the possibility of imbalance caused by imbalance, especially during spin phases. Therefore, the invention relates not only to working on the front loader washing machines, but means all trained with a drum shaft for driving a laundry drum machines for washing and / or drying laundry, so for example washing machines according to the Topladerprinzip, which is a top to be filled laundry drum have, working machines or dry cleaning machines.

According to the invention, the machine for determining and processing load-relevant parameters or an imbalance comprises at least one magnetic field sensor unit with which the magnetic field of a magnetized area moved with the drum shaft or the laundry drum is to be detected. This magnetic field sensor unit has, for example, a plurality of magnetic field sensors, so that, in addition to the determination of parameters correlating with forces and moments, it is also possible, for example, to determine without contact the axial position of the drum shaft. Among other things, a sensor operating according to the Hall principle is suitable as sensor type. In other words, the relevant load characteristics can be determined directly in the vibration system and not only their effect, for example in the form of speed fluctuations of the washing drum. Moreover, it is not necessary to set the washing drum in rotation in order to be able to determine unbalance-related parameters via the deflections that occur only during its rotation. Since the determination of the occurring forces and moments according to the invention takes place contactlessly on the drum shaft, the parameters relevant for the treatment of an existing unbalance can be measured directly and without wear on the component with the most direct load. In addition, the magnetostrictive property of the magnetizable materials preferably used is an inherent, wear-free property.

For the construction of the machine according to the invention, only a sensor unit with a small footprint preferably has to be arranged in the easily accessible area of the drum shaft, so that a more compact and less expensive construction of the machine can be realized.

A particularly simple embodiment of the magnetized region moved along with the drum shaft can be created in that the already present drum shaft itself is made at least in regions from a material having magnetic properties. In this case, all parameters relevant to the treatment of an imbalance of the laundry drum can be detected directly on the drum shaft, since both the forces and moments generated by the laundry in the area of the washing drum on the one hand and the forces and moments generated by the drive unit on the other hand act directly on the drum shaft.

Alternatively, it has proven to be particularly advantageous to drum shafts, which themselves have no or insufficient magnetic properties, for example, positively and / or positively connected to a co-moving component, for example in the form of an externally arranged sleeve. As a result, the magnetized area moved along with the drum shaft can be created in an extremely simple manner by the co-moving component. In addition, it would be conceivable to provide for already developed machines a solution by which the advantages of the invention can be realized later. In addition, the use of an additional magnetizable component allows the drum shaft to be made of a material which can be chosen independently of its magnetic properties. In addition, the required magnetic field for realizing the invention can be lowered to a strictly necessary minimum cost.

For the realization of the magnetic range ferromagnetic materials with the highest possible magnetostriction constant - such as steel no. 1.4057 with the short name X17CrNi16-2 - used, so that according to the invention the forces and moments occurring in and on the drum shaft or its associated component transformed the effect of the inverse magnetostriction into correspondingly large, easily detectable changes in the magnetic field formed by the material can be. This allows the use of less expensive magnetic field sensor units with lower sensitivity.

A structurally particularly useful and compact arrangement results when the magnetic field sensor unit is embodied within the bearing arrangement in such a way that it is arranged in the central region between two bearings forming the rotatable support of the drum shaft. This is also sensible in view of the maximum deflection of the drum shaft between the bearings, which arises, for example when the washing drum is stationary due to the gravity effect of the laundry on the one hand and the pulling action of the drive unit on the other hand, as well as rotating centrifugal force due to the centrifugal force of the circulating imbalance caused by the laundry ,

If the magnetic field sensor unit is connected to a control device of the washing machine, advantageously results in the possibility of evaluating the parameters determined by the sensor unit and specifically intervene in the flow of the wash program, so that a situation-dependent minimization of the occurring imbalance effect can be achieved or preventively completely prevented ,

In a further advantageous embodiment, the dynamic parameter values occurring on the drum shaft are determined by the magnetic field sensor unit. These torque values include, first of all, various torques, such as the torque generated by the drive torque of the drive unit, the torque produced by non-uniform mass distribution in the laundry drum, and the torques resulting from friction in the bearing assembly and friction of the wash drum with the surrounding air or wash liquor, etc. Furthermore, one of these parameter values is a torsional moment, which is formed by the interaction of the drive torque at one end of the drum shaft with the torque produced by the inertia of the loaded laundry drum at the other end within the drum shaft. Another parameter value may be a bending moment of the drum shaft caused by the unbalanced centrifugal force, which rotates with the drum shaft when viewed from the outside. Finally, the arrangement of a further magnetic field sensor in the magnetic field sensor unit, which determines the instantaneous axial position of the drum shaft via the measurement of a permanently magnetized region connected to the drum shaft, and thereby an exact determination, is particularly advantageous the angular velocity and / or the instantaneous angle of rotation of the washing drum allows.

Another important parameter value for targeted unbalance treatment is the total weight of the laundry introduced into the washing drum. This can be inventively determined by direct determination of the static force on the drum shaft bending force, since this is composed only of system design dependent, to be assumed constant values and the variable weight of the laundry. This parameter is proportional to the weight of the laundry and independent of the rotation angle position of the laundry drum. It is therefore particularly suitable for determining the weight of the laundry. It should be noted that the weight of the laundry during the washing process by different degrees of humidity changes over time.

In the method according to the invention, it is provided that the load-relevant parameters or unbalance parameters on the drum shaft or the laundry drum are first determined via the magnetic field sensor unit and corresponding control and / or control parameters for the current washing process are derived as a function of these parameters. Advantageous embodiments of the device according to the invention are to be regarded as advantageous embodiments of the method according to the invention.

In a particularly advantageous embodiment of the method according to the invention, the bending, torsional and / or torsional moments occurring on the drum shaft and the instantaneous angle of rotation or the instantaneous angular speed of the drum shaft are determined in the dynamic process state. This makes it possible to accurately determine the position of the imbalance-causing mass distribution within the laundry drum. In the static process state, the bending force currently acting on the drum shaft, via which the weight of the laundry to be introduced into the washing drum, is preferably determined.

The determined force, torque and / or angular speed values can be evaluated in a preferred manner by the control device of the machine. This evaluation allows the immediate derivation of control and regulation parameters and thus targeted intervention in the washing process to limit and / or preventive avoidance of imbalance.

For the method is further provided as advantageous that targeted by the derived control and regulation parameters, the instantaneous speed and / or the angular velocity of the laundry drum is varied, whereby on the one hand, a limitation of unbalanced, acting on the washing unit forces is achieved, and on the other hand Possibility exists to eliminate the imbalance largely or completely with targeted distribution of unevenly distributed in the washing drum laundry.

Fig. 1

eine schematische Schnittansicht durch eine als Frontladerwaschmaschine ausgebildete Maschine zum Waschen und/oder Trocknen von Wäsche mit einer über eine Trommelwelle angetriebene Wäschetrommel und mit einer im Bereich einer Lageranordnung der Trommelwelle angeordneten Magnetfeldsensoreinheit zur Ermittlung von belastungsrelevanten Kenngrößen bzw. einer Unwucht der Wäschetrommel bzw. der Trommelwelle,

Fig. 2

eine weitere schematische Schnittansicht durch die als Frontladerwaschmaschine ausgebildete Maschine zum Waschen und/oder Trocknen von Wäsche gemäß Fig.1, wobei die Durchbiegung der Trommelwelle schematisch angedeutet ist, welche durch die gemeinsame, schwerkraftbedingte Gewichtskraft der Wäschetrommel und des Waschguts einerseits und der durch die Riemenspannung des Antriebsriemens erzeugten Riemenspannkraft andererseits erzeugt wird,

Fig.

3 eine schematische Vorderansicht auf die Wäschetrommel der Maschine zum Waschen und/oder Trocknen von Wäsche gemäß den Fig. 1 und 2, wobei die schematische Wirkung der Schwerkraft auf eine am Außenumfang der Wäschetrommel befindliche, durch die Ungleichverteilung des Waschguts hervorgerufene Masse schematisch angedeutet ist; und in

Fig. 4

eine schematische Vorderansicht auf die Wäschetrommel sowie eine schematische Schnittansicht durch die Maschine zum Waschen und/oder Trocknen von Wäsche gemäß den Fig. 1 bis 3, wobei die Wirkung einer am Außenumfang der Wäschetrommel wirkenden, durch eine Unwuchtmasse hervorgerufenen Fliehkraft während eines dynamischen Waschprozesses schematisch angedeutet ist.

Further advantages, features and details of the invention will become apparent from the following description of a preferred embodiment and from the drawings; this show in:

Fig. 1

a schematic sectional view of a machine designed as a front loader washing machine for washing and / or drying laundry with a driven drum shaft and a drum arranged in the region of a bearing arrangement of the drum shaft magnetic field sensor unit for determining load-relevant characteristics or an imbalance of the laundry drum or drum shaft .

Fig. 2

a further schematic sectional view of the designed as a front loader washing machine for washing and / or drying of laundry according to Fig.1 wherein the deflection of the drum shaft is schematically indicated, which is generated by the common gravitational weight force of the laundry drum and the laundry on the one hand and the belt tension force generated by the belt tension of the drive belt on the other hand,

FIG.

FIG. 3 is a schematic front view of the laundry drum of the laundry washing and / or drying machine according to FIGS Fig. 1 and 2 , wherein the schematic effect of gravity on a located on the outer circumference of the laundry drum, caused by the unequal distribution of the laundry mass is indicated schematically; and in

Fig. 4

a schematic front view of the laundry drum and a schematic sectional view through the machine for washing and / or drying of laundry according to the Fig. 1 to 3 , wherein the effect of acting on the outer circumference of the laundry drum, caused by an imbalance mass centrifugal force during a dynamic washing process is indicated schematically.

Of a trained in the present embodiment as a front loader washing machine for washing and / or drying of laundry is in Fig. 1 in a schematic sectional view of an arranged within a washing machine housing, not shown washing tub 10, in which a laundry drum 12 is mounted on one side via a bearing assembly 13. The laundry drum 12 is connected via a drum shaft 14 with a pulley 16, which transmits the torque of a drive unit to the drum shaft 14 of the laundry drum 12 via a drive belt, not shown. The drum shaft 14 is held by two bearings 20 of the bearing assembly 13, which are in turn received within a bearing housing 18 at a distance from each other. In the present embodiment, the bearings 20 are formed as ball bearings. The bearing housing 18 is in turn firmly connected to the rear wall of the tub 10.

In a central region between the two bearings 20, a magnetic field sensor unit 22 is accommodated within the bearing housing 18, which comprises one or a plurality of magnetic field sensors. In addition to the preferred arrangement of the magnetic field sensor unit 22 provided here in the middle between the two bearings 20, it would of course also be conceivable to arrange them closer to one of the two bearings 20. The magnetic field sensor unit 22 detects the magnetic field of a magnetized area 24 moved with the drum shaft 14, which in turn is arranged in the area of the magnetic field sensor unit 22. In the present embodiment, the drum shaft 14 itself is at least partially made of a material with corresponding magnetic or magnetostrictive properties. However, in the context of the invention as encompassed with it is to be considered that a drum shaft 14 may be used, for example, even has no or only insufficient magnetic properties and includes a co-moving component, for example in the form of an externally arranged sleeve, which force, for example - and / or positive is connected to the drum shaft 14. The magnetized portion 24 of the drum shaft 14 is preferably made of a ferromagnetic material having a high magnetostriction constant, for example, Steel No. 1.4057, so that an inexpensive magnetic field sensor unit 22 having a relatively low sensitivity can be used. Due to the magnetostrictive properties of the magnetized portion 24 moving with the drum shaft 14, the mechanical deformation of the drum shaft 14 is transformed into a change of the magnetic field formed by the magnetized portion 24. This change in the magnetic field is detected contactlessly by the magnetic field sensor unit 22.

und andererseits durch das Biegemoment M_R der Riemenspannkraft F_R über den Hebelarm I_r des an der Riemenscheibe 16 angeordneten Antriebsriemens nach der Gleichung $${\mathrm{M}}_{\mathrm{R}}\mathrm{=}{\mathrm{F}}_{\mathrm{R}}\mathrm{*}{\mathrm{I}}_{\mathrm{r}}$$

erzeugt. Die Wirkungsrichtungen der Riemenspannkraft und der durch die Gravitationskraft erzeugten Gewichtskräfte sind in diesem Beispiel vereinfachend als parallel angenommen. Da die Riemenspannkraft F_R des Antriebsriemens, die Gewichtskraft der Wäschetrommel F_T und die Hebelarme I_t und I_r für ein Gerät als konstant angesehen werden können, ist bei stehender Waschtrommel 12 die mit der Biegelinie 33 dargestellte Durchbiegung bzw. Biegespannung der Trommelwelle 14 nur noch von der Gewichtskraft F_W des in der Wäschetrommel 12 vorhandenen Waschguts abhängig. Die Richtung dieser Biegespannung ist konstant und unabhängig von der Drehwinkelstellung der Wäschetrommel 12. Fig. 2 shows in a further sectional view through the front loader washing machine according to Fig. 1 The bending is shown on the one hand by the bending moment M _{T of} the jointly acting weight forces F _{T of} the laundry drum 12 and F _{W of} the laundry on the lever arm I _t according to the equation $${\mathrm{M}}_{\mathrm{T}}\mathrm{=}\left({\mathrm{F}}_{\mathrm{T}}\mathrm{+}{\mathrm{F}}_{\mathrm{W}}\right)\mathrm{*}{\mathrm{I}}_{\mathrm{t}}$$

and on the other hand by the bending moment M _{R of} the belt tension F _R on the lever arm I _r of the arranged on the pulley 16 drive belt according to the equation $${\mathrm{M}}_{\mathrm{R}}\mathrm{=}{\mathrm{F}}_{\mathrm{R}}\mathrm{*}{\mathrm{I}}_{\mathrm{r}}$$

generated. The directions of action of the belt tensioning force and the weight forces generated by the gravitational force are assumed to be parallel in this example for simplicity. Since the belt tension F _{R of} the drive belt, the weight of the laundry drum F _T and the lever arms I _t and I _r can be considered as constant for a device, is standing with the washing drum 12, the deflection or bending stress of the drum shaft 14 shown only with the bending line 33 still dependent on the weight F _W of existing in the laundry drum 12 laundry. The direction of this bending stress is constant and independent of the rotational angle position of the laundry drum 12th

An exact determination of the weight of the laundry is thus possible in a simple manner on the basis of the bending line 33 shown bending or bending stress of the drum shaft 14. The central arrangement of the magnetic field sensor unit 22 in the area of the maximum load or deflection of the drum shaft 14 and the correspondingly large changes in the magnetic field formed by the magnetized area due to the effect of the inverse magnetostriction thereby allow easy detectability by the magnetic field sensor unit 22. Accordingly, the use is less sensitive and therefore cost magnetic field sensors possible, whereby the relevant parameters for the treatment of imbalance effects - the torque, the torsional moment, the bending force, the mass of the laundry and the rotation angle of the laundry drum 12 - can be detected without contact and wear.

Fig. 3 shows a schematic front view of the laundry drum 12 of the machine for washing and / or drying of laundry according to the Fig. 1 and 2 , The following explains how torques can be determined which are transmitted from the pulley 16 via the drum shaft 14 to the laundry drum:

The driving torque, which is introduced via the pulley 16 in the drum shaft, while the following torques are opposite: moments of inertia in accelerating or delaying the rotational movement of the laundry drum 12, frictional moments due to friction in the bearings 20 and between the laundry drum 12 and the surrounding air or Washing liquid, and with the drum rotation changing torques due to the acceleration of the laundry drum 12 located on the outer circumference of the laundry.

In Fig. 3 this is the unbalance, acting on the outer circumference 34 of the rotating with a certain speed drum 12 weight F _FG . shown. Upon rotation of the laundry drum 12 at a certain speed or angular velocity ω above the application speed of the laundry can be formed by uneven mass distribution with the mass m _u a resulting imbalance. The application speed is to be understood as the speed at which a force acting on the laundry centrifugal force is equal to or greater than acting on the laundry gravity, so that the laundry is immobilized on the inner wall of the laundry drum. The unbalance causing mass m _u with the weight F _UG must be raised during a complete rotation of the laundry drum 12 in the upward movement against gravity. In the downward course of the rotation of the laundry drum 12, however, it is accelerated by gravity. Due to the cyclically changing lever arm h _t , a sinusoidal torque curve M _UG is produced on the drum shaft 14, which results in a torsional voltage changing with the drum shaft rotational speed or angular velocity ω whose amplitude depends on the magnitude of the resulting imbalance. Thus, the following equation results for the torque curve M _UG : $${\mathrm{M}}_{\mathrm{UG}}\mathrm{=}{\mathrm{F}}_{\mathrm{UG}}\mathrm{*}{\mathrm{H}}_{\mathrm{t}}\mathrm{*}\sin \left(\mathrm{.omega.t}\right)$$

Therefore, the position and size of the imbalance in the washing drum 12 can be determined exactly by the evaluation of the determined load-relevant parameters. By deriving appropriate control and / or regulation parameters, a targeted intervention in the washing process to reduce or even completely eliminate the imbalance effect is possible.

Finally, in Fig. 4 in a schematic front view of the laundry drum 12 and a schematic sectional view through the machine according to the Fig. 1 to 3 another load case of the washing machine and the recoverable parameter values or load-relevant parameters shown. Here, a bending moment M is particularly _UF determined as a result of the washing drum 12 acting at the outer periphery 34 of the centrifugal force of the unbalanced mass m _u. If an imbalance develops during a spin operation with the drum shaft speed or angular velocity ω above the application speed of the laundry due to a mass misalignment, this generates a centrifugal force F _UF acting on the outer circumference 34 (radius r _t ) of the wash drum 12. This centrifugal force F _UF is formed by the equation: $${\mathrm{F}}_{\mathrm{UF}}\mathrm{=}{\mathrm{m}}_{\mathrm{u}}\mathrm{*}{\mathrm{\omega }}^{\mathrm{2}}\mathrm{*}{\mathrm{r}}_{\mathrm{t}}$$

This centrifugal force F _UF generates a bending moment M _UF via the lever arm I _u , which in turn causes a bending stress in the drum shaft 14. Since the direction of this tension relative to the magnetized drum shaft 14 is constant, from the outside seen but with the drum shaft speed or angular velocity ω rotates, the magnetic field sensor unit 22 detects a circulating at the drum shaft speed or angular velocity ω signal, which depends on the size of the mass distribution and its axial location on the outer circumference 34 of the washing drum 12. The bending moment M _UF is the cause of the actual drum shaft load.

On the basis of the load-relevant parameters or unbalance parameters determined by the magnetic field sensor unit 22, control and / or control parameters of the machine can be derived as a function of the determined values in a subsequent method step. The derivation of the control and / or regulation parameters of the machine takes place by means of a control device of the machine which is present anyway and which is present in any case. By way of the control device, which is connected to the drive of the machine, it is possible, for example, to change the rotational speed or the angular speed of the laundry drum as a function of the control and / or regulation parameters and thus to reduce or completely eliminate an imbalance due to an uneven distribution of the laundry , For this purpose, it is conceivable, for example, to change the rotational speed or the angular velocity of the laundry drum 12 abruptly and possibly only for a short period of time, whereby a more even distribution of the laundry can be realized.

Claims (12)

1. Machine for washing and/or drying laundry, particularly according to the principle of front-loading, comprising a drum shaft (14), which is rotatably mounted by means of a bearing arrangement (13), for drive of the laundry drum (12) and a device for determining load-relevant characteristic values or an imbalance of the laundry drum (12) or the drum shaft (14) on the basis of a laundry load, wherein the device for determining load-relevant characteristic values or an imbalance comprises at least one magnetic field sensor unit (22) by which the magnetic field of a magnetised region (24) moved together with the drum shaft (14) or the laundry drum (12) is to be detected, characterised in that the magnetised region (24) consists of a ferromagnetic material with a magnetostrictive constant of such level that forces and moments arising in and at the drum shaft (14) or a component connected with the drum shaft (14) are transformed by the effect of the inverse magnetostriction into correspondingly large, easily detectable changes in the magnetic field formed by the material.
2. Machine according to claim 1, characterised in that the magnetised region (24) is provided at the drum shaft (14) of the laundry drum (12).
3. Machine according to claim 1 or 2, characterised in that the drum shaft (12) itself is made in at least a region from a magnetisable material which forms the magnetised region (24).
4. Machine according to claim 1 or 2, characterised in that the drum shaft (12) comprises a component moved together therewith, particularly a sleeve part surrounding this at the outer circumference, which component consists at least in a region of a magnetisable material forming the magnetised region (24).
5. Machine according to claim 3 or 4, characterised in that the magnetisable material is a ferromagnetic steel with magnetostrictive characteristics.
6. Machine according to any one of the preceding claims, characterised in that the bearing arrangement (13) comprises two bearings (20), between which the at least one magnet field sensor unit (22) is arranged preferably at at least approximately the same spacing from the two bearings (20).
7. Machine according to any one of the preceding claims, characterised in that the at least one magnetic field sensor unit (22) is connected with a control device of the machine, by which the rotational speed or the angular speed (ω) of the laundry drum (12) is to be set.
8. Machine according to any one of the preceding claims, characterised in that by means of the at least one magnetic field sensor unit (22) at least one dynamic parameter value, particularly a rotational and/or torsional moment (M_UG) and/or bending moment (M_UF) and/or the dynamic bending forces (F_UF) and/or the angular speed (ω) of the drum shaft (14), is to be determined.
9. Machine according to any one of the preceding claims, characterised in that by means of the at least one magnetic field sensor unit at least one static parameter value, particularly a static bending force (F_T, F_R, F_W) and/or bending moment (M_T, M_R) arising at the drum shaft (14), is to be determined.
10. Method for determining and processing load-relevant characteristic values or imbalance parameters of a laundry drum (12) or of a drum shaft (14) of a machine for washing and/or drying laundry on the basis of a laundry load, particularly according to any one of claims 1 to 9, comprising the steps:

    a) determining the load-relevant characteristic values or the imbalance parameters by means of at least one magnetic field sensor unit (22), by which the magnetic field of a magnetised region (24) moved together with the drum shaft (14) or the laundry drum (12) is detected; and

    b) deriving control and/or regulating parameters of the machine in dependence on the load-relevant characteristic values or imbalance parameters determined by the magnetic field sensor unit (22),

    characterised in that the magnetic field is formed from a ferromagnetic material with a magnetostrictive constant of such a level that forces and moments arising in and at the drum shaft (14) or a component connected with the drum shaft (14) are transformed by the effect of the inverse magnetostriction into correspondingly large, easily detectable changes in the magnetic field formed by the material.
11. Method according to claim 10, characterised in that in step a) a rotational and/or torsional moment (M_UG) and/or a bending moment (M_UF, M_T, M_R) and/or at least one bending force (F_UF, F_T, F_R, F_W) and/or the angular speed (ω) of the drum shaft or the laundry drum (14) is or are determined by means of the magnetic field sensor unit (22).
12. Method according to claim 10 or 11, characterised in that the derivation of the control and/or regulating parameters in step b) is performed by a control device of the machine.

Images