DE102008021598A1 - Clothes drying apparatus and method for controlling a drying operation of the laundry drying apparatus - Google Patents

Abstract

The dryer (W) has a control unit (C) for controlling a drying process based on sensor data of a magnetic field sensor unit and a three dimensional hall sensor (31), which is arranged at the dryer in a fixed manner. The magnetic field sensor unit is arranged at a shaft stub at a rear wall of a laundry drum (2) of the dryer. A permanent magnet is arranged at the laundry drum. The magnetic field sensor unit is arranged to sense deflection of a drum shaft (23). A drum housing (1), in which the laundry drum is rotatably supported for receiving clothes (3). An independent claim is also included for a method for controlling a drying process.

Description

The Invention relates to a laundry drying apparatus, in particular washer-dryer, and a method for controlling a Drying process of a clothes drying machine, especially washer dryers.

Prior art washer-dryers show the documents WO 2007/138019 A1 such as EP 0 636 732 B1 . DE 44 27 361 A1 and DE 195 22 307 C2 , The three last-mentioned documents primarily each describe a washer-dryer which has a water-cooled condenser for drying wet laundry by means of a circulating process air stream.

A sensor unit comprising magnetic field sensors in a machine for washing and / or drying laundry emerges from US Pat WO 2007/118512 A1 , This sensor unit can also be referred to as a "magnetic field sensor unit". It serves to determine load-relevant parameters or imbalance parameters of a laundry drum. For this purpose, these parameters are detected by the sensor unit and fed to a control unit of the machine, where control or regulation parameters for the operation of the machine, in particular in a spin process, are derived from these parameters. The sensor unit can be designed such that it can detect load-relevant parameters in three dimensions. It can then be called a "3D sensor". A method for controlling a spin cycle in a washing machine and a correspondingly improved washing machine are apparent from the WO 2008/006675 A1 ,

at a simple washer-dryer or clothes dryer a drying period set directly by a user. One advanced washer-dryer or tumble dryer and sets the duration of the drying cycle automatically. At a pure tumble dryer is a conductivity measurement on the dried becoming the most widespread procedure. Also included are temperature measurements to determine the moisture content of the laundry used. Also known is the use of an air humidity sensor for measuring the air humidity of the process air leaving the drum. However, the use of such a humidity sensor is expensive, yes because the production of such a sensor is expensive.

A modern washing machine can in particular according to WO 2007/118512 A1 be equipped with a working according to a magnetic principle sensor unit to monitor the system movements during spin and thereby avoid attacks of the vibration system on the housing and overloading of the system by imbalance. In addition, such a sensor is used to carry out a weighing of the filled laundry after loading the washing machine, also to warn him against overcharging the machine and to issue recommendations for the amount of detergent to be dispensed. The operating principle is that the suspension system suspended on springs changes its position as a function of the charged load. It sinks down by gravity. The degree of system lowering is a measure of the amount of filled laundry. The designed as a 3D sensor sensor unit detects this movement and the controller calculates from this with the help of the spring constant of the suspension, the load. The 3D sensor, which operates as a load sensor in this way, is mounted in the upper area on the rear wall of the oscillating system and designed as a 3D Hall sensor. On the movably suspended part of the oscillating system, a permanent magnet is attached. The 3D Hall sensor measures the direction and field strength of the magnetic field caused by the permanent magnet. The pairing of these values is clearly attributable to a relative position to the permanent magnet. As a result, the position of the magnet relative to the Hall sensor can be determined.

Also is for determining a loading weight of a washing machine One-dimensional displacement sensor known in a vibration damper is housed and also for said weighing can be used.

It The object of the present invention is a possibility for inexpensive and relatively inexpensive laundry moisture dependent To provide control of a drying process, in particular to determine a duration of the drying process.

These Task is by means of a clothes dryer and a method according to the respective independent claim solved. In particular, preferred embodiments are The dependent claims can be removed.

The laundry drying apparatus, in particular a washer-dryer or a pure laundry dryer, is equipped with a control unit for controlling a drying operation, which is adapted to control the drying operation on the basis of sensor data of a loading sensor, in particular a magnetic field sensor unit, in particular a 3D sensor. The signal of the loading sensor is thus optionally used in addition to the known functions for monitoring and controlling the drying process. In this case, different measured values can be obtained and control information derived.

By Using the signals of one to monitor the spin process In a washing machine known 3D sensor now also for control a drying process, including a pure clothes dryer, In particular, one of the humidity of the laundry to be dried can be directly dependent control especially for one Realize washer-dryer without additional sensor technology. Appropriate Measurements can also be made with other measuring methods (conductance measurement, temperature measurement) combine to increase the detection accuracy of the data to be dried Increase laundry and as targets of a drying process each desired Endrestfeuchten with improved accuracy to reach.

Of the Loading sensor may be any type of loading sensor, for. B. a one-dimensional displacement sensor. However, it is preferred if the loading sensor is a magnetic field sensor unit, in particular a Hall sensor. The magnetic field sensor unit is flexible and without major conversions can be used and also wear-resistant and accurate.

It is preferred for particularly easy attachment when the load sensor comprises a Hall sensor which is stationary on the laundry drying device is arranged, for. B. backward to the laundry drum, in particular on a rear wall of the laundry drying device, and a permanent magnet disposed on the laundry drum is.

It may also be preferred if the magnetic field sensor unit to is arranged and arranged to sense a deflection of a drum shaft.

Also for use on a simple clothes dryer according to the invention Use of a magnetic field sensor unit taught. As it is a simple Tumble usually no problem with imbalances as with a washing machine in the case of a spin process, is the storage of a laundry drum in a tumble dryer easier and without complex oscillating system executable. In general, the laundry drum is a tumble dryer on a stub shaft on a rear wall of the laundry drum stored and in addition via rollers, on a flanged edge of the filling opening the laundry drum run, supported. It can a magnetic field sensor unit - especially in one opposite a 3D sensor simplified version - on attached to the stub shaft and for weighing the Wäschepostens to be used.

The Method for controlling a drying process of such a laundry drying device has at least the step of detecting a loading weight (a weighing) by means of the loading sensor.

there The weighing can be carried out with the washing drum stopped be, for example, before the beginning of a drum rotation or during a reversing of the drum.

It is used to avoid the influence of static friction in one Vibration damper, however, preferred when weighing performed on a rotating laundry drum becomes. For this purpose, advantageously, the load weight by means of Load sensor several times (i.e., at least twice) in time sensed and then averaged. Preferably is a period of time consecutive Sensing (measuring time) a multiple of one for one revolution of the laundry drum required time since so the influence of a laundry-related imbalance in the drum is reduced.

It is further preferred if the method further comprises the step of Detecting one, in particular maximum, spin speed during a preceding to the drying process wash and from it Determining a residual moisture content (only with washer-dryer). Of the Relationship between the achievable residual moisture in dependence The spin speed is typically device-specific Parameters (eg design, speed curve during spin, esp. Spinning time)) and is therefore preferred determined experimentally for each device type. The maximal Spin speed has the biggest impact on the achieved residual moisture. It is preferably in every washing process redetermined as it is due to user preferences or occurrence of unbalance-dependent reductions in spin speed can be influenced.

It may be preferred when determining the residual moisture from the spin speed calculating the residual moisture from a corresponding Calculation function with spin speed as calculation parameter includes.

It may be preferred when determining the residual moisture Determining the residual moisture from the spin speed by means of a corresponding table of values.

It is further preferred if the method comprises the step of determining a lot of moisture in the laundry to be dried the residual moisture and the loading weight has.

It is further preferred if the method further comprises the step of Determine one needed for the drying process Duration of the previously determined amount of moisture and a known Has drying rate.

It is used to account for changes in process variables preferred when the method comprises the step of determining a Energy required for the drying process from the previously determined amount of moisture and a known device effectiveness index having.

Then it is particularly preferred if the method further comprises the step determining a required for the drying process Duration from the previously determined amount of energy and under determination a cumulative introduced by a heater in the process Has amount of energy.

It but may also be preferred if the method further comprises the step determining a required for the drying process Duration of the previously determined amount of moisture and a means the load sensor measured weight loss of the laundry having.

Then it is preferred when measuring a weight of the laundry in the Reversierpausen with standing laundry drum or with rotating drum and calculation of the mean over several Drum rotations takes place, z. B. as stated above, especially if the incurred immediately before weighing Condensation in the drum area removed by the pumping device becomes.

Generally For example, a process may be preferred in which to control the drying process Weight loss per unit time is monitored, in particular, if for controlling the drying process a residual moisture level, in particular of about 15%, from a reduction in weight loss per unit time is determined. From the vorbestimm th residual moisture level, in particular of about 15%, then the drying process z. B. by another Procedure be continued, z. B. as described above or z. On the basis of a conductance. Preferably this time of reaching the predetermined residual moisture level directly used to switch to the cooling phase, if the laundry should be slightly damp at the end (8-10%), z. B. for ironing ("ironing"). If a dryer laundry is desired, then preferably a time-controlled further drying section whose duration is constant or depends on the until time required at this time (eg large Loading - long time up to 15% - long dry period; small load - short time up to 15% - short drying time).

In The following figures illustrate the invention with reference to exemplary embodiments described in more detail schematically. It can for better clarity identical or equivalent elements with the same reference numerals be provided.

1 shows a sectional view in cross-sectional view designed as a front loader washing machine for washing and / or drying of laundry;

2 shows a flowchart for determining a drying time according to a first embodiment;

3 shows a flowchart for determining a drying time according to a second embodiment;

4 shows a flowchart for determining a drying time according to a third embodiment;

5 shows a flowchart for determining a drying time according to a fourth embodiment;

6 shows a schematic sectional view through the machine designed as a front loader washing machine for washing and / or drying of laundry 1 with the laundry drum driven by a drum shaft and with a magnetic field sensor unit arranged in the region of a bearing arrangement of the drum shaft for ascertaining load characteristics or an imbalance of the laundry drum or the drum shaft;

7 shows a further schematic sectional view through the machine according to 6 wherein the deflection of the drum shaft is schematically indicated, which is generated by the common, gravitational weight 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;

8th shows a schematic front view of the laundry drum of the machine for washing and / or drying of laundry according to the 6 and 7 , 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

9 shows a schematic front View of the laundry drum and a schematic sectional view through the machine for washing and / or drying laundry according to the 6 to 8th , 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.

1 shows components of a designed as a front load washer dryer W with air condensation cooling, which is in the state after a wash and before a drying cycle. The washer-dryer has a drum housing or tub 1 in which a laundry drum 2 (Inner drum) for receiving laundry 3 is rotatably mounted. By means of a fresh water supply line 4 put in a dispenser dish 5 opens with water, with or without detergent additive to the drum housing 1 (Outer drum, tub) supplied and forms there the free fleet 6 , The over a heater 7 warm up free fleet 6 can by means of a drain pump 8th through a drainage channel 9 be drained to the outside.

Additionally is on the tub 1 a circulating air or process air duct 10 connected to the process air. The upper part 11 of the process air channel 10 is with the pressure side of a process air blower 12 connected and opens with its other end in the drum housing 1 above the filling opening (not shown here) the Wäschetrom mel 2 , The lower part 13 of the process air channel 10 is to the suction side of the process air blower 12 connected and opens in a lower area in the drum housing 1 , This estuary 14 but still above the level ever reached by the wash or rinse liquor. In the upper part of the canal 11 is typically still arranged a heater, not shown here for heating the process air. In drying operation, the process air is blown by the blower 12 blown through the heater, heated there and then mixed in the laundry drum with the wet laundry. There, the heat energy is used to evaporate the water in the laundry. The air is then in a condensation device 15 cooled and returned to the blower 12 directed.

For this purpose, the designed as a heat exchanger condensation device 15 which is essentially a cooler 16 has, in a lower part 13 of the process air channel 10 appropriate. The cooler is cooled by fresh air coming from the environment of the washer dryer W from a cooling fan 17 sucked in and over the cooling air inlet channel 18 the radiator 16 is supplied. After flowing through the radiator 16 and absorption of heat energy from the process air, the cooling air through a cooling air outlet channel 19 to an exhaust air outlet 20 guided. When condensing the process air in the cooler accumulating condensate is via a downpipe 21 from the radiator housing to the drum housing 1 derived and pumped from there by means of a draining device for the dirty water from time to time in the sewage system. The downpipe 21 is here as part of the process air channel 10 executed. During drying, this results in a transport of water from that in the drum 2 located laundry 3 outward. This reduces the weight of the laundry 3 and with it the power on the vibration system. The programs of the washer-dryer W are controlled by means of a control unit C.

The washer-dryer W is further provided with a magnetic load sensor attached to the rear 31 equipped, which is designed as a 3D Hall sensor, while on the movably suspended oscillating system, an unillustrated permanent magnet is mounted. As is well known, the 3D Hall sensor measures 31 a magnetic field direction and a magnetic field strength. The pairing of these values is clearly attributable to a relative position to the permanent magnet. This allows the position of the magnet relative to the Hall sensor 311 determine, and thus the loading weight.

In the case of a pure tumble dryer are only for washing the laundry 3 required elements, such as fresh water supply 4 and dispenser tray 5 , unavailable.

2 shows a flowchart for device-side determination of a drying time from a determination of the amount of water to be evaporated.

at This process is first in a step S10 a load the machine with a laundry item to be dried.

This is followed in a step S11 by a weighing of the inserted laundry item, ie, that a loading weight of the laundry item is detected, by means of the loading sensor. This can be done in a variant in the state standing internal drum. In a further, alternative or additional variant, the weighing takes place with the inner drum rotating. As the drum rotates, multiple readings are taken over a predetermined period of time and then averaged. By averaging the measured values, the problem of possible static friction in the vibration dampers, to which, among other things, the tub is suspended, can be overcome. The predetermined period of time is preferably a multiple of the time required for a drum rotation. The determined weight is the sum of dry laundry and the water contained in the wash.

In a subsequent step S12 is from a at last preceding (eg following the previous ones Wash cycle performed) spin cycle achieved maximum Spin speed to the residual moisture reached during the last spin, d. H. the relative proportion of remaining in the laundry Water, closed. It is assumed that this laundry item, or part of it, to be dried.

Of the Conclusion on the residual moisture from the spin speed is based on previously determined empirical values or preliminary tests. A correlation between spin speed and residual moisture can by means of a suitably formulated calculation function or via a table with known pairs of values from spin speed and Time (characteristic) done.

In Step S12 or a subsequent step S13 becomes from the residual moisture and the known load weight to be removed Amount of water determined. Will also be the one for a device known drying rate in g of removed water per min considered (which does not have to be constant), so will from this a time required for drying calculate and then controlled the drying program.

The Drying speed can, however, by external Influences be variable. So z. B. in an air condensation dryer, the condensation performance and thus the drying rate due to the temperature in the Storage room to be influenced. A better control parameter is therefore the amount of energy spent in drying.

3 shows a further flow chart for determining a device-side drying time from a determination of the amount of water to be evaporated.

In contrast to the expiration of 2 Now, after step S12, a step S21 of a determination of the amount of energy required for the drying follows. In this case, in the case of a known amount of water to be removed (step 12) and using the amount of energy known per device series, which is to be expended per g of water to be removed (device efficiency index Wh), the amount of energy required for the drying is calculated.

to Determination of the duration of the drying process in 822 now needs only during the drying program by observation the switching state of the heater using the known heating power the heating device introduced by the heater in the process Amount of energy to be summed up and with the pre-calculated amount of energy to be compared. Upon reaching the pre-calculated amount of energy is the drying process ended. The determination of the duration takes place Here therefore not at the beginning of a drying process, but will determined during the drying process in a timely manner. Thereby also changes in the process parameters, such as a change the ambient temperature, etc., taken into account.

4 shows a flowchart for determining a device-side drying time by measuring the amount of water removed. After step S12, in which now the weight of the dried laundry is calculated, in step S31 a new weighing is carried out regularly by means of the loading sensor, and indeed, as already described for step S11, standing in the state internal drum during a Reversierpause and / or at rotating inner drum. Subsequently, in step S32, the previously measured loading weight is compared with the weight of the dried laundry calculated in step S12. If the measured loading weight has decreased so far that it has reached the weight of the dried laundry, the drying process is terminated.

Around a measurement error due to condensed water collected in the drum system is prevented, in step S33 immediately before weighing the accumulated condensation water removed by the pumping device. So for such a weighing has a synchronization the sub-processes drum reversion, pumping down and measured value acquisition to be done.

5 shows a flow chart for determining a device-side drying time by measuring the temporal change (the gradient) of the removed amount of water. In this process, no knowledge about a residual moisture of the invited laundry item is needed.

After the start of the program, the system waits until the system has heated up and a relatively constant process state is established (step 41). This initially leads to a constant drying rate, which is essentially limited by the dryer performance, and thus to a time uniform weight reduction. At the end of drying, the evaporation rate and thus also the amount of condensate per unit of time decrease. This allows a conclusion on the residual moisture of the laundry: in cotton textiles z. B. at about 15% residual moisture of the laundry evaporates the water located on the surface of the fibers. The evaporation of the in The capillary water stored in the fibers requires more time and energy. The drying process slows down. This reduction of the condensate flow (the amount of condensate removed per unit of time) is thus an indicator of the attainment of a residual moisture content of about 15%. This is evident in a reduction in the gradient of the weight curve or a reduction in the gradient of weight reduction.

In the illustrated sequence, a weighing is performed at regular intervals in step 42. In step S43, a reduction in the weight reduction per unit time or the gradient of the weight reduction is observed. If the weight reduction per unit of time or the gradient of the weight reduction falls below a certain threshold value - relative or absolute - then the attainment of a residual moisture content of about 15% can be recognized and responded to on the control side. The weighing in step S42 is preferably done after the step of pumping out the accumulated water in step S44. In the 5 sketched method is suitable for both pure dryers and washer-dryers. When using a pure tumble dryer it is equipped with a loading sensor, eg. B. a 3D loading sensor whose attachment is particularly simple.

6 shows in a sectional view of the tub or drum housing 1 in which the laundry drum 2 via a bearing arrangement 22 arranged on one side. The laundry drum 2 is over a drum shaft 23 with a pulley 24 connected via a drive belt, not shown, the torque of a drive unit on the drum shaft 23 the laundry drum 2 transfers. The drum shaft 23 is by two bearings 25 the bearing arrangement 22 held, which in turn within a bearing housing 26 are recorded at a distance from each other. In the present embodiment, the bearings 25 designed as a ball bearing. The bearing housing 26 is in turn stuck to the back wall of the tub 1 connected.

In a central area between the two camps 25 is inside the bearing housing 26 a magnetic field sensor unit 30 which includes one or a plurality of magnetic field sensors. In addition to the preferred arrangement of the magnetic field sensor unit provided here 30 in the middle between the two camps 25 Of course, it would be conceivable to bring these closer to one of the two bearings 25 to arrange. Through the magnetic field sensor unit 30 the magnetic field becomes one with the drum shaft 23 moving magnetized area 27 detected, which in turn in the field of magnetic field sensor unit 30 is arranged. In the present embodiment, this is the drum shaft 23 itself at least partially made of a material with corresponding magnetic or magnetostrictive properties. However, in the context of the invention as encompassed, it is to be considered that also a drum shaft 23 can 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 circumferentially arranged sleeve which, for example, non-positively and / or positively with the drum shaft 23 connected is. The magnetized area 27 the drum shaft 23 is preferably made of a ferromagnetic material with a high magnetostriction constant - for example steel No. 1.4057 - designed so that a cost-effective magnetic field sensor unit 30 can be used with a relatively low sensitivity. Due to the magnetostrictive properties of the drum shaft 23 moving magnetized area 27 becomes the mechanical deformation of the drum shaft 23 in a change of the through the magnetized area 27 transformed magnetic field formed. This change in the magnetic field is caused by the magnetic field sensor unit 30 detected without contact.

7 shows in a further sectional view through the front loader washing machine according to 6 schematically the one with the bending line 28 illustrated deflection of the drum shaft 23 , The deflection is on the one hand by the bending moment M _{T of} the jointly acting weight forces F _{T of} the laundry drum 2 and F _{w of} the laundry over the lever arm I _t according to the equation M T = (F T + F w ) · I t and on the other hand by the bending moment M _R of the belt clamping force F _R on the lever arm I _r of the on the pulley 24 arranged drive belt according to the equation M R = F R · I 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 2 the one with the bend line 28 illustrated bending or bending stress of the drum shaft 23 only from the weight F _W in the laundry drum 2 depending on existing laundry. The direction of this bending stress is constant and independent of the rotational angle position of the laundry drum 2 ,

An exact determination of the weight of the laundry is thus easy on the basis of the bending line 28 illustrated bending or bending stress of the drum shaft 23 possible. The central arrangement of the magnetic field sensor unit 30 in the area of the maximum load or deflection of the drum shaft 23 as well as by the effect of the inverse magnetostriction correspondingly large changes in the magnetic field formed by the magnetized area allow easy detection by the magnetic field sensor unit 30 , Accordingly, the use of insensitive and therefore inexpensive magnetic field sensors is possible, whereby the parameter values relevant 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 2 - Can be detected contactless and wear-free.

8th shows a schematic front view of the laundry drum 2 the machine for washing and / or drying laundry according to 6 and 7 , The following explains how torques can be determined from the pulley 24 over the drum shaft 23 be transferred to the laundry drum:
The drive torque, which via the pulley 24 is introduced into the drum shaft, while the following torques are opposite: moments of inertia in accelerating or retarding the rotational movement of the laundry drum 2 Frictional moments due to friction in the bearings 25 and between the laundry drum 2 and the surrounding air or washing liquid, and with the drum rotation changing torques due to the acceleration of the outer circumference of the laundry drum 2 located laundry.

In 8th this is the unbalance caused, on the outer circumference 29 the laundry drum rotating at a certain speed 2 acting weight F _ug shown. During rotation of the laundry drum 2 With a certain rotational speed or angular velocity ω above the application speed of the laundry, a resulting imbalance can be formed by uneven mass distribution with the mass m _u . 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 imbalance mass m _u with the weight F _ug must be during one complete revolution of the laundry drum 2 be raised in the upward movement against gravity. In the downward course of the rotation of the laundry drum 2 however, it is accelerated by gravity. Due to the cyclically changing lever arm h _t arises at the drum shaft 23 a sinusoidal torque curve M _ug which results in a torsional strain varying with the drum shaft speed ω whose amplitude depends on the magnitude of the resulting imbalance. Thus, the following equation results for the torque curve M _ug : M ug = F ug ·H t * Sin (.omega.t)

Therefore, the position and size of the imbalance in the washing drum can be determined by the evaluation of the determined load-relevant parameters 2 be determined exactly. 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 9 in a schematic front view of the laundry drum 2 and a schematic sectional view through the machine according to the 6 to 8th another load case of the washing machine and the recoverable parameter values or load-relevant parameters shown. In this case, in particular a Biegemo element M _UF due to a on the outer circumference 29 the washing drum 2 acting centrifugal force of imbalance m _u ascertainable. If, during a spin process with the drum shaft speed or angular velocity ω above the application speed of the laundry, an imbalance develops due to a mass misalignment, this creates an imbalance on the outer circumference 29 (Radius r _t ) of the washing drum 2 acting centrifugal force F _UF . This centrifugal force F _UF is formed by the equation: F UF = m · ω 2 · r t

This centrifugal force F _UF generates a bending moment M _UF via the lever arm 1 _u , which in turn generates a bending stress in the drum shaft 23 caused. Because the direction of this voltage relative to the magnetized drum shaft 23 is constant, but seen from the outside with the drum shaft speed or angular velocity ω rotates, detects the magnetic field sensor unit 30 a circulating with the drum shaft speed or angular velocity ω signal, which depends on the size of the mass distribution and its axial position on the outer circumference 29 the washing drum 2 depends. The bending moment M _UF is the cause of the actual drum shaft load.

Due to the magnetic field sensor unit 30 determined load-related parameters or unbalance parameters can be derived in a subsequent process step control and / or control parameters of the machine as a function of the determined values. 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, the rotational speed or the angular velocity of the laundry drum 2 Abruptly and possibly only for a short period of time to change, which can be realized a more uniform distribution of the laundry.

In particular, it is possible to determine from the characteristics of the magnetic field sensor unit 30 determine the weight F _{w of} the laundry and use to control the drying process, as already detailed by way of example with respect to the 1 to 5 described. Of course, the present invention is not limited to the embodiments shown.

Thus, the processes and sub-processes shown in the above embodiments can be applied individually or combined to achieve higher reliability. These processes can also be combined with other methods for controlling a drying process, for. B. based on a conductivity measurement or temperature measurements. For example, the processes, in particular the process can be 5 , be combined with a determination of the drying progress, in particular the residual moisture, from the performance of the process air / cooling air heat exchanger. These processes can also be used for certain areas of the residual moisture or drying time and can be supplemented or replaced by other processes in sections. The degree of drying to be achieved can be chosen variably, z. B. ironed, cupboard dry, etc. and may depend on a selected textile.

In particular, the loading sensor can also be used in a pure tumble dryer, in particular to determine the drying process. It can be as in the above 6 to 9 described loading sensor can be used, or any other loading sensor, for. B. a one-dimensional displacement sensor. In this case, the invention makes use of the fact that the laundry introduced into the laundry drum of the tumble dryer loads and shifts the laundry drum and / or exerts a measurable bending moment on the drum shaft driving the laundry drum.

1

drum housing

2

washing drum

3

Laundry

4

Fresh water supply

5

dispenser tray

6

free fleet

7

heater

8th

Drain pump

9

drain channel

10

Process air duct

11

upper Part of the process air duct

12

Process air fan

13

lower Part of the process air duct

14

muzzle

15

condensation device

16

cooler

17

Cooling fan

18

Cooling air inlet channel

19

Cooling air outlet channel

20

exhaust air outlet

21

penstock

22

bearing arrangement

23

drum shaft

24

pulley

25

camp

26

bearing housing

27

magnetized Area

28

elastic line

29

outer periphery

30

Magnetic field sensor unit

C

control unit

F _R

Belt tension force

F _T

weight force the laundry drum

F _UF

centrifugal

F _ug

weight force

F _w

weight force of the laundry

I _t

lever arm

I _r

lever arm

l _u

lever arm

M _R

Bending moment

M _UF

Bending moment

M _ug

torque curve

r _t

radius the laundry drum

S10-S54

process steps

W

Laundry drying device

ω

angular velocity

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 2007/138019 A1 [0002]
• - EP 0636732 B1 [0002]
• - DE 4427361 A1 [0002]
• DE 19522307 C2 [0002]
• - WO 2007/118512 A1 [0003, 0005]
• - WO 2008/006675 A1 [0003]

Claims (17)

Laundry drying device (W) with a control unit (C) for controlling a drying process, characterized in that the control unit (C) is adapted to the drying operation on the basis of sensor data of a load sensor ( 30 ; 31 ) to control. Laundry drying apparatus (W) according to claim 1, characterized in that the loading sensor is a magnetic field sensor unit ( 30 ; 31 ), in particular a Hall sensor ( 31 ). Laundry drying apparatus (W) according to claim 2, characterized in that the loading sensor is a Hall sensor ( 31 ), which is arranged stationarily on the laundry drying apparatus (W), and a permanent magnet attached to the laundry drum ( 2 ) is arranged. Laundry drying apparatus (W) according to claim 2, characterized in that the magnetic field sensor unit ( 30 ) is arranged and arranged, a deflection of a drum shaft ( 23 ) to be felt. Clothes drying device (W) after one of claims 1 to 4, characterized in that the Clothes dryer (W) a clothes dryer is. Laundry drying apparatus (W) according to claims 2 and 5, characterized in that the magnetic field sensor unit ( 30 ) is arranged on a stub shaft on a rear wall of a laundry drum of the tumble dryer. Method for controlling a drying process of a laundry drying apparatus (W) according to one of claims 1 to 6, characterized in that the method comprises the following step: (a) detecting a loading weight (F _w ) by means of the loading sensor (S11). A method according to claim 7, characterized in that step (a) in a standing laundry drum ( 2 ) is carried out. A method according to claim 7, characterized in that step (a) in a rotating laundry drum ( 2 ), wherein the detection of the loading weight (S11) comprises a chronologically successive sensing and subsequent averaging of a plurality of measured values of the loading weight (F _W ). A method according to claim 9, characterized in that a time duration of the temporally successive sensing of the plurality of measured values is a multiple of one for one revolution of the laundry drum ( 2 ) time required. Method according to one of claims 7 to 9 for controlling a drying process of a clothes dryer (W) according to one of claims 1 to 4, characterized that the method further comprises the following step: (B) Detecting a, in particular maximum, spin speed during a preceding to the drying process wash and from it Determining a residual moisture. A method according to claim 11, characterized in that the method further comprises the following step: (c) determining an amount of moisture from the residual moisture and the loading weight (F _W ) (S12). Method according to claim 12, characterized in that that the method further comprises the following step: (D) Determine a needed for the drying process Duration of the previously determined amount of moisture and a known Drying rate (S13). A method according to claim 12, characterized in that the method further comprises the steps of: (d) determining an amount of energy required for the drying process from the predetermined amount of moisture and a known device efficiency index (S21); (e) determining a time period required for the drying process from the previously determined amount of energy and determining one by a heating ( 7 ) Cumulated energy amount introduced into the process (S22). A method according to claim 12, characterized in that the method further comprises the following step: (d) determining a time required for the drying process from the previously determined amount of moisture and a by means of the loading sensor ( 30 ) measured weight decrease of the laundry (S31, S32). A method according to claim 15, characterized in that immediately before the weighing accrued condensation by the pumping device ( 8th ) is removed (S33, S44). A method according to any one of claims 7 to 16, characterized in that the method of controlling the drying process comprises the steps of: (f) monitoring a weight loss per time unit (S42); and (g) determining a residual moisture level, in particular about 15%, from a decrease in weight loss per unit time (S43).