DETECTION AND ADJUSTMENT OF GARMENT CLOTHING FOR AN AUTOMATIC WASHING MACHINE DESCRIPTION OF THE INVENTION The invention relates to a method for detecting the degree of piling of articles in an automatic laundry washing machine. Automatic clothes washers can be found anywhere. Such appliances clean cloth items efficiently, allowing the owner to complete other tasks or to engage in more satisfying activities while washing clothes. Modern clothes washers provide a large number of options to adjust a selected cleaning operation to the type of fabric comprising the wash load and the degree of soiling of the wash load. This includes setting a liquid level appropriate for the size and type of fabric of the wash load. Modern clothes washers also include sophisticated controllers that are programmed to maximize cleaning efficiency while minimizing water and energy consumption. However, despite the capabilities of modern clothes washers, the apparatus remains limited in its ability to detect clutter and then adjust the wash cycle based on the real-time information related to the cloth items being washed. . A type of automatic clothes washers
conventional can be provided with a drive motor, generally electrically driven, which can be used to propel a cylindrical perforated basket during a centrifugation cycle, and a clothes stirrer during the washing and rinsing cycles to stir the charge of washing inside the basket. In an automatic washing machine for conventional clothing, the cleaning of cloth items can be attributed mainly to three factors: chemical energy, thermal energy and mechanical energy. These three factors can be varied within the limits of a particular automatic washing machine to obtain the desired degree of cleanliness. Chemical energy refers to the types of washing aids, for example, detergent and bleach, applied to cloth articles. Under normal conditions, the more cleaning aids are used, the greater the cleaning effect will be. Thermal energy refers to the temperature of cloth articles. The temperature of the washing liquid typically constitutes the source of thermal energy. However, other heating sources can be used. For example, a known form uses steam to heat cloth articles. Under normal conditions, the higher the thermal energy, the greater the cleaning effect. Mechanical energy can be attributed to contact
between the clothes stirrer and the fabric articles, the contact between the cloth articles themselves, and the passage of the washing liquid through the cloth articles. In washing machines with a clothes stirrer, the clothes stirrer tends to cause the fabric articles to contact each other, and for the washing liquid to pass through the fabric articles. Under normal conditions, the greater the amount of mechanical energy, the greater the cleaning effect. These three factors can be adjusted to obtain the desired cleaning effect. For example, although direct contact between the clothes stirrer and the fabric articles can be beneficial for washing, it also causes greater physical wear of the fabric articles than the other two factors. In this way, for example, for more delicate clothes, you want to reduce direct contact. However, with contemporary washing machines, it has not yet been possible to determine the mechanical energy imparted to the fabric articles during the washing process. In this way, contemporary solutions are based on estimates or empirical data, of which both are typically determined based on a set of standard test conditions. Unfortunately, it is not guaranteed that these standard test conditions will be repeated when the consumer uses the clothes washer, which results in compromised cleaning.
It may be advantageous for the overall cleaning performance if the mechanical energy imparted to the fabric articles could be determined during the washing process. A method and apparatus for determining the degree of stacking of the fabric articles during a washing process. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: Figure 1 is a partially sectioned elevational view of an automatic laundry washing machine according to the invention illustrating the relevant internal components thereof, including a laundry basket and a laundry stirrer. clothes . Figure 2 is a partially sectioned perspective view of the laundry basket and the clothes stirrer illustrated in Figure 1. Figure 3 is an enlarged partially sectioned view of the laundry basket and the clothes stirrer illustrated in FIG. Figure 2, which shows an article of clothing in a first configuration in relation to the clothes agitator. Figure 4 is a view of the laundry basket and clothes stirrer illustrated in Figure 3, showing the laundry article in a second configuration in relation to the laundry stirrer.
Figure 5 is a view of the laundry basket and clothes stirrer illustrated in Figure 3, showing the laundry article in a third configuration in relation to the laundry stirrer. Figure 6 is a schematic representation of cloth items in a non-stacked condition in the laundry basket. Figure 7 is a schematic representation of cloth articles in a state stacked in the laundry basket. Figure 8 is a first graphical representation of engine speed and engine current for the automatic laundry washing machine illustrated in Figure 1, which contains only liquid during a single cycle of the clothes stirrer consisting of a forward rotating stroke followed by a rotating race backwards. Figure 9 graphically depicts engine speed and engine current for the automatic laundry washing machine illustrated in Figure 1, which contains liquid and a wash load without stacking during a single cycle of the clothes stirrer consisting of a rotating stroke forward followed by a rotating race backwards. Figure 10 graphically represents engine speed and motor current for the washer
clothing automatic illustrated in Figure 1, which contains liquid and a wash load with stacking during a single cycle of the clothes stirrer consisting of a forward rotating stroke followed by a reverse rotary stroke. The invention relates to a method for determining the degree of piling of articles in a clothes washer based on the mechanical energy imparted to the cloth articles by the coupling of a clothes stirrer with cloth articles in a washing load. The invention may also include a method for adjusting a wash cycle based on the given stacking. The method utilizes operational characteristics of a drive motor, such as current and speed, to determine the degree of clutter of the fabric articles. The degree of stacking of the fabric articles can be compared with the predetermined threshold for the degree of stacking to control the operation cycle by the introduction of liquid into the clothes washer, by setting the stroke of the agitator, or by stopping the cycle. Conventional clothes washers allow a user to select one of several washing options based on the type of laundry load that is placed in the laundry washer. For example, eligible options may include "normal," "delicate," "wool," and the like.
These are typically referred to as "cycles." As used herein, "the wash cycle" will refer to a specific cycle, such as "normal", which extends from the beginning of the cycle to its completion. A wash cycle consists of at least one wash cycle, a rinsing cycle and a centrifugation cycle. The washing cycle, the rinse cycle and the centrifugation cycle may consist of several stages, such as a filling stage, a drain stage, a pause stage, a stirring stage and the like. The invention can be used with any cycle independently of the types and the combination of stages. Figure 1 illustrates an embodiment of the invention consisting of an automatic vertical clothes washing machine 10 comprising a cabinet 12 having a control panel 14, and enclosing a liquid-tight tub 16 that defines a washing chamber in which can be placed a perforated basket. In this way, the cloth items placed in the basket 18 are placed in the washing chamber. A clothes stirrer 20 adapted to impart movement to a wash load contained within the basket 18 can be arranged in the lower part of the basket 18. The laundry stirrer 20 is illustrated as a low profile vertical shaft driver. However, the clothes stirrer 20 can also be a shaft agitator
vertical, with or without an endless screw, or a basket adapted with peripheral vanes. The clothes stirrer 20 and the basket 18 can be aligned coaxially with respect to a vertically oriented oscillation axis 22. Although the invention will be illustrated with respect to a low profile impeller, other garment agitators may be used without departing from the scope of the invention. For example, it has been contemplated that the invention has applicability for horizontal axis washers as well as for vertical axis washers. For purposes of this application, horizontal axis washer refers to those types of washers that move cloth items primarily by lifting fabric articles and dropping them by gravity, regardless of whether the axis of rotation is primarily horizontal, and washing machine Vertical axis refers to those types of washing machines that move cloth items by means of a clothes stirrer, regardless of whether the axis of rotation remains mainly vertical. The clothes stirrer 20 can be operatively coupled with a drive motor 28 via an optional drive 26 and a drive belt 30. One or more well-known sensors 31 for monitoring the angular velocity, current, voltage and the like, can be operatively coupled with the motor 28. The results of the
sensors 31 may be sent to a controller 32 of the machine in the control panel 14. In many applications, the sensors 31 are part of an engine controller coupled with the controller 32 of the machine. The controller 32 of the machine can be adapted to send and receive signals to control the operation of the clothes washer 10, receive data from the sensors 31, process the data, display information of interest to a user, and the like. The laundry washer 10 can also be coupled with a water source 34 which can be distributed to the tub 16 through a nozzle 36 controlled by a valve 38 operatively coupled to the controller 32 of the machine. The valve 38 and the controller 32 of the machine can allow a precise volume of water to be distributed to the tub 16 for washing and rinsing. Figure 2 illustrates an embodiment of the invention with the laundry basket 18 and the laundry stirrer 20 in alignment coaxial with the oscillation axis 22. The laundry stirrer 20 may be a sheet-like, somewhat circular body having a plurality of radially extending vanes 40 extending upwardly thereof. The pallets 40 can be adapted to make contact and interact with the cloth articles and the liquid in the rack 18 to agitate the cloth articles and the liquid. During a wash cycle and a rinse cycle,
the laundry stirrer 20 can be propelled by the drive motor 28 for movement inside the washing chamber. The basket 18 can be braked to remain stationary during the movement of the laundry stirrer 20, or the basket 18 can rotate freely during the movement of the laundry stirrer 20. The drive motor 28 can propel the clothes stirrer 20 in an oscillating manner, first in a forward direction, referred to herein as a forward stroke, then in a backward direction, referred to herein as a "backward stroke". . The clothes stirrer 20 can move in a forward direction through a preselected angular displacement, for example, ranging from 180 ° to 720 °. The clothes stirrer 20 can be moved in a backward direction through a preselected angular displacement. A full forward and reverse race are referred to herein as an oscillation cycle. For clothes agitators that move in a revolving manner, the forward and backward runs are usually referred to as clockwise and counterclockwise. Although typically the forward race constitutes the race in the clockwise direction and the race backwards constitutes the
In a counter-clockwise direction, these relationships can easily be reversed. In a typical wash cycle, multiple fabric articles, which collectively form a wash load, are placed in the basket on top of the laundry stirrer 20. Some of the cloth items will be in direct contact with the clothes stirrer 20 and some will not. As the clothes stirrer 20 moves, the individual fabric articles will be moved directly or indirectly by the clothes stirrer 20 to impart mechanical energy to the articles, which will move the cloth items around the interior of the washing chamber . In Figure 3, one embodiment of the invention shows a single fabric article 50 in a lower portion of a wash load that will be in contact with the laundry agitator 20. The illustration does not include liquid for clarity; however, it should be understood that the liquid exists and can be found at any level from just moistening the fabric articles to completely submerging the fabric articles. The article 50 of fabric can be represented by a weight factor 52 directed in descending order. The vanes 40 terminate at an upper vane edge 54. All or part of the pallet 40 can make contact with the fabric article 50 during the forward and backward runs of the clothes stirrer 20. As the clothes stirrer 20 rotates
in a forward stroke, represented by the movement vector 42, a pallet 40 may come into contact with the fabric article 50. Figure 4 shows an embodiment where the contact of the pallet 40 with the fabric article 50 tends to move the fabric article 50 in the direction of rotation of the garment agitator 20, represented by a traction vector 56. The illustration does not include liquid for clarity; however, it should be understood that the liquid exists and can be found at any level from just moistening the fabric articles to completely submerging the fabric articles. Due to the weight of the fabric article 50, the weight of the underlying fabric articles, the friction ratio between the fabric article 50 and the blade edge 54, the degree of wetting of the fabric article 50, and other factors, there may be intermittent gripping and sliding by the pallet 40 in relation to the fabric article 50, which will be reflected in the movement of the fabric article 50 which may not be the same rotational distance as that of the clothing agitator 20, resulting in the relative movement between the article 50 of cloth and the clothes stirrer 20. As illustrated in Figure 5, if there is sufficient slip, at some point during the forward stroke, the paddle 40 can be separated from the fabric article 50.
The intermittent gripping and sliding of the pallet 40 with respect to the laundry agitator 20 results in an intermittent application of the weight of the fabric article 50 towards the laundry agitator 20, which amounts to a loading and unloading of the laundry agitator 20. The loading and unloading present themselves as a change in the speed of the clothes stirrer 20, which can be detected by the sensors 31. In response, the controller 32, which typically attempts to move the motor 28 at a set speed predetermined during the given cycle, will increase or decrease the current to the motor 28 to try to maintain the set speed. The magnitude and frequency of grip and slip can be affected by several factors, of which only some will now be described. The greater the size of the wash load, the greater the weight of the load of the other fabric articles in the fabric article in direct contact with the laundry stirrer 20. The increased volume of the higher wash load will also tend to inhibit free movement of the fabric articles within the wash chamber. Wet cloth items tend to create a greater frictional resistance with the clothes stirrer than with dry fabric articles. However, as the level of liquid in the wash chamber increases to the
At the point where the cloth articles are totally submerged, the additional liquid carries out the flotation of the cloth articles, which has an opposite effect to that of the weight force of the cloth articles. In some cases, the liquid may be deep enough and the laundry stirrer may sufficiently agitate the liquid part of or all the fabric articles are suspended in the liquid on the clothes stirrer 20, which will significantly reduce the load of the clothes stirrer 20 using the cloth articles. In this way, under normal conditions, the deeper the liquid, the more the degree of loading and unloading will be reduced. Additional washing liquid also tends to interfere with the ability of the clothes stirrer 20 to reverse the direction of the fabric articles when the fabric stirrer 20 changes direction between the forward and backward strokes. For example, when the clothes stirrer 20 moves in a forward stroke, it causes not only that the fabric articles move in the forward direction of travel, but also that the liquid in the washing chamber moves in one direction. of forward race. By reversing backwards, fabric articles in direct contact with the clothes stirrer 20 will tend to follow the reverse stroke direction of the laundry stirrer 20. However, the liquid, especially the liquid above the clothes stirrer 20, will tend to maintain
the movement in the direction of race back due to its moment. In this way, the inversion of the clothes stirrer 20 does not necessarily result in all fabric and liquid articles in the reversing direction of the washing chamber at the same time as the laundry stirrer 20. Figure 6 is a schematic representation of a fabric load comprising fabric articles 2 shown in a non-piled state. The fabric articles 2 are considered non-stacked where they are distributed relatively uniformly in the washing liquid 4 in the laundry basket 18. Uniform distribution can be desired for optimal efficiency and effective cleaning. Uniform distribution allows the clothes stirrer 20 to move forward and backward and allows uplift of the fabric articles. The outcrop is the overturning of the fabric articles in the wash load and is desired since it promotes uniform cleaning of the fabric articles. A common form of outcrop occurs when cloth items move between the bottom of the basket and up to the top of the liquid. The movement may also include cloth articles that move in and out radially from the center of the basket to the peripheral wall of the basket. In Figure 7, the fabric articles 2 can
pile up during the wash cycle. During the wash cycle, the stacked fabric items 3 are piled on one side and no longer distributed evenly within the laundry basket. The stacking can be thought of as several fabric articles operatively coupled so that they effectively behave as a single mass. This can cause an asymmetric load on the clothes stirrer. The operative coupling may arise for one or more reasons, examples include: the cloth articles may be in an overlapping condition and their weight and / or friction resistance tends to keep the condition overlapped; cloth items can be interwoven or rolled together; and the cloth items can be twisted together. The stacking of the fabric articles in the laundry basket 18 can have several different disadvantageous effects in the laundry machine 10. For example, a common disadvantage may be that the mechanical energy imparted to the fabric articles by the laundry stirrer 20 may be focused primarily on the outside of the stacked laundry articles, which minimizes the cleaning effect on the interior fabric articles. . The cleaning effect can be reduced because the washing liquid 4 may not pass through the cloth items 3 stacked as easily as if the clothes were distributed more evenly. The cleaning effect can also
reduce because the piled cloth items 3 are not able to move relative to each other and impart mechanical energy to each other. Piled-up clothing can also move asymmetrically within the laundry basket even though the clothes shaker typically rotates at the same distance for forward and backward strokes. The phenomena of asymmetrically moving clothing occurs because the heaped load of clothing has a greater inertia than a uniformly distributed load and may be less likely to change direction of rotation along with the laundry agitator. Phenomena can occur more easily when the level of liquid filling increases in the washing chamber due to the increase in the flotation force decreases the weight of the laundry that acts on the clothes stirrer, which makes it easier than clothes piled up separate from the clothes stirrer. The increased liquid also increases the likelihood of asymmetrical movement of the clothing because the liquid rises further on the clothes stirrer, the liquid may be less sensitive to the movement of the clothes stirrer. For example, the liquid immediately adjacent to the clothes stirrer may be more sensitive to the movement of the clothes stirrer and tends to follow its direction. The farther the liquid may be from the clothes stirrer, the less sensitive it may be since the liquid
of intervention must transfer the forces from the clothes agitator. The liquid also has its own inertia. In this way, once movement is established by the clothes stirrer, the liquid as it moves further away from the clothes stirrer will not be affected mainly by the change of direction of the clothes stirrer. While heaped garments or deeper filling can cause asymmetrical movement of clothing, the combined effect of garments heaped in deeper filling wash cycles makes it more likely that piled clothing does not follow the movement of the garment shaker. In some cases, the effect may be large enough so that the clothes piled up generally move in only one direction in the wash tub. When piled clothing does not respond to the clothes agitator, the cleanliness of piled clothes can be reduced since there may be less mechanical energy imparted to clothes piled up from the impeller, reduced fluid flow through clothing, and less contact from clothes to clothes. The pile-up can be more disadvantageous since during the washing operations, where the laundry shaker oscillates or centrifugation operations, where the washing basket rotates, but especially during the centrifugation operations, the piled-up clothes can cause an imbalance condition what large enough for the wash basket to lose its suspension and / or contact a
Cabinet portion 12, which can be very undesirable. The stacking can also lower the speed of the motor since the pallets of the impeller of the clothes agitator contact the stacked fabric articles. In response, the controller 32, which typically attempts to move the motor 28 at a predetermined set speed for the given cycle, will increase the current to the motor 28 to try to increase the motor torque and maintain the set speed. The additional motor current results in increased costs for the customer. Figure 8 graphically illustrates a waveform of the engine speed 70 and the engine current 72 during an oscillation cycle of the clothing agitator 20 through a forward stroke, represented by a forward direction region 74, followed by the movement in a backward stroke, represented by a region 76 of backward direction. The waveforms of Figure 8 are generated by sampling the engine speed 70 and the engine speed stream 72 at a predetermined interval or sampling rate, which in this case constitutes 20 milliseconds. As illustrated, in the forward direction region 74, the laundry stirrer 20 can accelerate rapidly at a predetermined set speed 74a, stay at the predetermined set speed 74b, and then
decelerate quickly 74c, which may include braking, before the investment. The regions 74b can often be referred to as the stagnation period. The backward direction region 76 may similarly be divided into an acceleration stage 76a, a stagnation period 76b and a deceleration stage 76c. In this way, when the clothes stirrer 20 is changed from the forward stroke to the backward stroke, the motor current 72 decreases to a null value 94, and the motor speed 70 responsibly decreases to a null value 96. or almost nil. While the decrease in velocity may not be shown to go to zero in Figure 8, this results from the sampling ratio for the data points-the null velocity was not sampled-in any indication that the velocity is not reduced to zero. In reality, whenever the clothes stirrer changes direction, there must necessarily be a point, which can be instantaneous, where the speed is equal to zero. During the forward and backward runs as illustrated in Figure 8, the controller controls the engine speed in an attempt to maintain engine speed at a predetermined set speed, which for the example in Figure 8 constitutes 110 rpm. . In this way, the speed of the clothes stirrer 20 remains essentially constant at approximately the set speed of 110 rpm in the period 74b, 76b of
is curve anchor 70. There are nominal variations or fluctuations in the magnitude of the motor current and the motor speed in the stalling period 74b, 76b due to the nominal charge and discharge of the liquid in the clothes stirrer 20 associated with the coupling of the laundry stirrer 20 with the liquid as the laundry stirrer 20 moves through the liquid. This loading and unloading is transmitted through the clothes stirrer 20 and the transmission 26 to the drive motor 28 where it can be detected by the speed sensor 31. The loading and unloading causes temporary changes in the speed of the clothes stirrer 20 in relation to the set speed. In response, the controller 32 adjusts the current to the motor 28 in an attempt to maintain the set speed, which results in the motor current carrying the velocity as easily seen in Figure 8. Figure 9 graphically illustrates the shapes of wave for the signals of the motor current 72 and the speed 70 of the motor that can be attributed to the loading and unloading of the clothes stirrer 20 when there is a load of fabric articles 50 generally well distributed in the washing chamber during a oscillation cycle of the clothes stirrer 20. Figure 9 illustrates the waveforms of engine speed 70 and engine current 72 where the set point of the engine speed constitutes 120 rpm and the proportion
Sampling is equal to 20 milliseconds. The intermittent gripping and sliding of the cloth articles 50 with the blades of the laundry agitator 20 is transmitted through the clothes stirrer 20 and the transmission 26 to the drive motor 28, where it manifests as fluctuations in the wave forms of the clothes. Engine speed and motor current. These fluctuations define a waveform that has multiple peaks. The peaks have greater magnitude than those fluctuations in Figure 8 due to the larger force associated with the wash load when compared to the liquid only. A peak in the waveform is an indication of the coupling between the clothing and the impeller and does not illustrate stacking. Looking more closely at the fluctuations of the motor speed waveform at an approximately well distributed load, the fluctuations can be separated into peaks comprising peaks 82a-d, 86a-d positive and peaks 84a-d, 88a-d negative . The amplitude of magnitude of the fluctuations can be determined by comparing the peaks with the set point of the motor speed. For example, the difference between the positive speed amplitude 82 and the target rotation speed can be a first amplitude value. Similarly, the difference between the negative speed amplitude 84 and the target rotation speed, expressed as an absolute value, can
be a second amplitude value. The average frequency of fluctuations can be determined by counting the number of positive / negative peaks during a given period of time or by taking the velocity of the wave and dividing by its wavelength. The waveforms of the motor speed and the motor current have a quasi-sinusoidal waveform for which a frequency can be determined using the positive / negative peaks during the time of stagnation period 74b, 76b. The current waveform of the motor in a roughly distributed load shows a waveform similar to the speed of the motor with the current tending to drive the speed. The conduction of the current in relation to the motor speed results from the controller that tries to maintain the motor speed at the set speed. Because the magnitude of the current depends on the controller trying to maintain the set speed, the motor current has no corresponding set point in the way that the motor speed has a set point. The amplitude values and the frequency values for either or both of the motor speed and the motor current can be stored by the controller 32 of the machine as individual data values as well as a cumulative value. The amplitude values can be averaged
and, more preferably, an accumulated average of the amplitude values can be determined and stored by the controller 32 of the machine. The frequency values can also be averaged and, more preferably, a moving average of the frequency values can be determined and stored by the controller 32 of the machine. The averages can be calculated over a set or variable time or established or variable amount of movement of the clothes agitator. The averages can be temporary averages or cumulative averages. Figure 10 shows an example of current and velocity waveforms that are indicative of stacking. Looking more closely at the fluctuations of the motor current waveform of Figure 10, the forward run 74 has four positive peak points 92a-d while the backward race 76 has eight points 95a-h peak positive. It has been determined that the inconsistency between the number of peaks indicates that there is stacking. This is because in the forward stroke the load is pushed in a forward or clockwise motion by the clothes stirrer 20. However, when the clothes stirrer 20 is in the backward stroke, the piled clothes may not be effectively pushed by the backward stroke. In fact, the clothes stirrer 20 jumps under the
stacked fabric articles 3 and stacked fabric articles 3 do not immediately follow the clothes shaker * and may continue in the forward direction. This asymmetry in the clothes and the movement of the basket manifests as asymmetry in the motor current waveforms between the forward and backward strokes. More specifically, it is believed that the increased frequency of the backward stroke can be caused due to the fact that the stacked fabric articles are not traveling with the clothes stirrer to the same degree as in the forward stroke, which results in a greater number separations and contacts between the piled clothes and the agitator blades clothing, which load / correspondingly download agitator clothes at a higher frequency, causing the engine to respond by increasing / decreasing the current / speed in an attempt to maintain established speed Thus, the agitator clothing can be thought as jumping under items piled fabric, with the jump resulting in an increased number of peaks in the backward stroke of the motor current and the waveforms of engine speed and as a reduction in the magnitude of the peaks. While the increased frequency in the backward run relative to the forward run indicates stacking, it has been determined that the
Frequency can be used to quantify the degree of stacking in addition to the existence of stacking. The degree of stacking of the fabric articles can be determined from the data of the motor current in real time. In this way, the use of the data by making a real-time sensor placed in the wash chamber to determine the degree of stacking. Such a sensor has never been available before. Applicants have also determined that the amplitude of the motor current can provide an accurate estimate of the degree of clutter of the fabric articles, thereby allowing an action to be carried out in a corrective action. The degree of stacking of the fabric articles in the wash load can be determined from the sample data of the forward and backward racing waveforms, more specifically by comparing the determined amplitudes of the forward and reverse runs. backward. For example, the sample data can essentially be compared on a point-by-point basis between the corresponding points for the forward and backward runs. The corresponding points can be thought of as even points. The comparison can be made by determining the difference in amplitude between the corresponding pairs points for the forward and backward runs. This difference can
determine for all points in pairs or some of the points in pairs. The difference can be determined on one or several cycles of oscillation. The difference can be traced as a simple difference, an accumulated total that can be weighed or not, or as a maximum difference trapped. The difference in amplitude can then be compared to a predetermined threshold and the degree of stacking can then be determined. The default threshold can be a range of values or a simple value. In most cases, it can be a simple value representing the threshold between acceptable and unacceptable stacking for the given washing machine. Applicants have also determined that one type of difference that can precisely determine the degree of stacking is the symmetry between the forward and backward runs of the motor current waveform. This asymmetry can be calculated from sample data of waveforms for both forward and backward runs. This can be done using the entire waveform for the race as part of the waveform. The asymmetry can be traced as a simple value, a cumulative total that can be weighted or not, or as a trapped maximum value. The asymmetry can provide an estimate of the degree of clutter of the fabric articles, which consequently allows for a
corrective action. The more symmetrical the waveforms are, the greater the degree of stacking estimated. A more detailed appearance in an implementation to determine the difference using the points in pairs should be useful to further understand the invention. It should be noted that the following implementation has been based on a quadratic means difference method, which has been found to provide the desired resolution to determine the degree of stacking for the contemplated washer; however, it can be seen that other mathematical methods can also be used. Observing Figure 10 as an example, the sample data of the clothes agitator motor current for the forward run in the twenty-fifth sample is represented as A. The sample data of the clothes agitator motor current for the backward stroke in the twenty-fifth sample is represented as B. The points A and B represent a set of points in pairs in the waveform of the motor current since each corresponds to the twenty-fifth sample during its respective stroke . In this way, the magnitude of each point in the forward stroke of the waveform can be compared to its counterpart in the backward stroke. In Figure 10, the sampling ratio results in that there are fifty sets of pairs of points. The mean square differenceit can be taken between such points in pairs. ? n = N n = 1. { J (CW, n) -I (CCW, n)} 2 where: I is the current signal; MSD_I is the mean square difference for the current signal; CW is a race in a clockwise direction of the clothes agitator; CCW is the anti-clockwise run of the clothes agitator; nN "is the total number of data points in pairs, and wn" is the data points in pairs of interest in the total number N of the data points in pairs. The number of points in N pairs can be through a complete oscillation cycle. Alternatively, it may be through more than one cycle or less than one cycle. The MSD_I value can then be compared to a threshold T to determine the degree of stacking. The following formulas represent the comparison made between MSD_I and the threshold value. (2) MSD_I > = T = Clothes pile up. { 3) MSD_I < T = Clothing does not stack The threshold value T will typically be determined empirically for different clothes washers, and
It will be established based on such factors as type of fabric, the size of the washing load, the washing cycle, the configuration of the clothes stirrer, the type of motor, the type of transmission, and the like. An MSD_I greater than or equal to the threshold value G indicates that the laundry is piled up. An MSD L less than the threshold value T indicates that clothes do not stack. Another implementation takes the average of the mean square difference determined by formula (1) for a number of mean square difference determinations, which can be represented by the formula:? m = M m = 1 MSD_I (m) where: represents the number of mean square difference determinations used to calculate the average; and m is the current mean square difference determination. It is currently contemplated that M will represent the number of oscillation cycles and the mean square difference MSD_I will be calculated for points of pairs that correspond to a complete oscillation cycle. In that way, MSD_IA will be an average of the mean square difference for multiple oscillation cycles. However, when the MSD I determination does not need to be on a base
of oscillation cycle, MSD_IA also does not need to be on an oscillation cycle basis. This MSD_IA can then be compared to its own value TA to determine the degree of stacking. The formulas in the following represent the comparison made between MSD_IA and the threshold value. (5) MSD_IA > = TA = Clothes are stacked (6) MSD_IA < TA = Clothing is not stacked An MSD_IA greater than or equal to the threshold value TA indicates that clothing is piled up. An MSD_IA less than the threshold value TA indicates that the laundry does not pile up. The methods represented by Formulas (l) and (4) can also be implemented as a moving average over a predetermined set of values, sets of points of pairs or determinations of mean square difference according to the case to be made. For example, a moving average using formula (1) could be calculated continuously using the most recent specific number of points of pairs such as the most recent 5 points, 50 points, 500 points or any number that is selected. The number of points of pairs can probably be based on the number of points of pairs required by a particular washing machine platform to provide the degree of stacking at a resolution necessary for the operation of the particular platform of the washing machine. For the
Formula (4), an average calculation of movement can also be implemented by collecting a predetermined number and the sequence of the quadratic mean difference terminations of formula (1), such as the last quadratic mean difference determination 5, 10 or 15. The number of mean square difference determinations will likely be based on the number required by a platform particular washing machine to provide the degree of stacking at a resolution necessary for the operation of the particular platform of the washing machine. An illustrative example of the use of stacking detection during the operation of the washing machine should be useful in understanding the stacking detection within the washing operation. During a filling stage in a wash cycle. The laundry stirrer 20 can be rotated through a preselected number of preliminary oscillation cycles., for example five, while the water is added to the washing chamber, or after an initial filling of the washing machine 10. In this way, the clothes stirrer 20 rotates through five strokes forward and five strokes backwards while the machine controller 32 is aware of the degree of stacking using the previously described method. This can be achieved by the machine controller that receives data samples of the motor current from the sensor 31, which stores the
values of the magnitude in the same time d $ specific sampling for each of the races forward and backward in the oscillation cycle, determine the mean square difference between the two points and maintain an average of the quadratic mean differences. At the end of a cycle, the average of the mean square difference, MSD_I can be compared with a preselected threshold value, T. Alternatively or additionally, a comparison can also be made at the end of the multiple cycles, where the value can be either moving average or not. The controller 32 of the machine uses the determination of the degree of stacking to control the operation of the laundry washer. Specifically, the controller 32 of the machine will take a corrective action to separate the stacked clothing if the quadratic difference equals or exceeds the threshold. It should be noted that other types of threshold comparisons may exist. As described, the determined value of the mean square difference is compared to one greater than or equal to the base. However, the threshold could be taken in such a way that the comparison can be made in a larger than the base, smaller than the base, or less than or equal to the base. The type of comparator can usually be controlled by how the threshold number is quantified. The default threshold value can represent a level of
optimal uniform distribution that reflects an optimal combination of cleaning effort and cleaning efficiency. An optimum level has been reached when the mean square difference or the average of the mean square difference reaches the preselected threshold value. Another way in which the motor current and speed information can be used to determine the degree of clutter is by using the jitter frequency of the current and motor speed waveforms. One way to use the frequency is to use an average frequency, which can include determining the average frequency for each of the forward and backward runs after comparing the determined average frequencies of the forward and backward runs. For example, the average frequency can be compared between the corresponding samples for the forward and backward runs. The corresponding samples can be thought of as sections in pairs of each race. The comparison can be made by determining the difference in the average fluctuation frequency between the forward and backward runs. This difference can be determined for any useful time segment or operation segment, such as: multiple oscillation cycles, a whole oscillation cycle, a whole oscillation cycle, or a portion of an oscillation cycle. The
Difference can be traced as a simple difference, an accumulated total that can be weighed or not, or as a maximum difference trapped. The difference of the frequencies can then be compared to a predetermined threshold and the degree of stacking can then be determined. The default threshold can be a range of values or a simple value. In most cases, it will be a simple value representing the threshold between acceptable and unacceptable stacking for the given washing machine. A more detailed observation in an implementation for determining the difference using frequency data should be useful to further understand the invention. It should be noted that the following implementation has been based on an average fluctuation frequency difference method, which has been found to provide the desired resolution to determine the degree of stacking for the contemplated washing machine; however, it can be seen that other mathematical methods can also be used. When using the data in Figure 10 for example, the frequency data of the motor speed of the clothes stirrer for the forward stroke is represented as 74. The motor current can also be used to determine the degree of stacking but this explanation will use only the engine speed. The frequency data of the speed of the clothes stirrer motor
for the backward run it is represented as 76. The longer wavelengths in forward run 74 correlate with race 74 forward which has a smaller frequency than race 76 backward which has a much higher frequency big and much shorter wavelengths. In this way, the average frequency for those samples can be determined from the waveform and can be compared as their counterpart in the forward or backward travel. Using the data in Figure 10 for the example, the average can be calculated on a per-run basis and then compared by taking the difference between the average frequencies for the forward and backward runs. In Figure 10, the sampling ratio was approximately fifty data points per run, resulting in fifty pairs of corresponding data points for the forward and backward runs. The difference in the average frequency difference can be taken between such even values using the formula: (l) delta_F = (Avg_F (W (CW, n)) -Avg_F (W (CCW, n).}. Where: W is already be the speed or the current signal; Delta_F is the difference between the average frequencies of the signal;
CW is a race in a clockwise direction of the clothes agitator; CCW is the race in the anti-clockwise direction of the clothing agitator; wn "is the number of samples used to determine the average frequency in each of the races in a clockwise and counterclockwise direction, and Avg_F is the average frequency of one of the races towards forward or backward for the samples "n" taken The delta value F can then be compared with a threshold T to determine the degree of clutter The following formulas represent the comparison made between delta_F and the threshold value deltaJF > = T = Clothing is piled up delta_F < T = Clothes do not stack The threshold value T will typically be determined empirically for different clothes washers, and will be established based on factors such as type of fabric, the size of the load washing, washing cycle, clothes shaker configuration, type of motor, type of transmission, and the like, a delta_F greater than or equal to the threshold value T indicates that the Opa piles up. A delta_F less than the threshold value T indicates that the clothing is not
pile up Another implementation takes the average of the mean square difference determined by the formula (1) for a number of frequency difference determinations, which can be represented by the formula: ^ - m = M (4) delta_FA = l / í _ m = 1 delta_F (m) where: M represents the number of frequency difference determinations used to calculate the average; and m is the speed or determination of current frequency difference. It is currently contemplated that M will represent the number of oscillation cycles and the frequency difference delta_F will be calculated for a sample that corresponds to a complete oscillation cycle. That way, delta_FA will be an average of the frequency difference for multiple oscillation cycles. However, when the delta_F determination does not need to be on an oscillation cycle basis, delta_FA does not need to be on an oscillation cycle basis either. This delta_FA value can then be compared to its own threshold TA to determine the degree of clutter. The following formulas represent the comparison made between delta FA and the threshold value.
(5) Delta FA > = TA = Clothes are stacked (6) delta_FA < TA = Clothes do not pile up A delta_FA greater than or equal to the threshold value TA indicates that clothes are piled up. A delta_FA less than the threshold value TA indicates that the laundry does not pile up. This implementation has two adjustable parameters that include M which represents the number of frequency difference determinations used to calculate the average and can be varied to include a greater or lesser number of determinations. A greater number of determinations can show the stacking for a longer period of time while a smaller number can be averaged over a shorter period of time. further, TA the threshold level can be adjusted to allow the clutter to be determined by the invention in smaller or larger amounts. By adjusting these parameters, the best performance can be extracted using this algorithm. Adjustable parameter values may also differ between speed based and current based algorithms. Although independent of the signal used, the underlying algorithmic metric and the concept are the same. The main reason for choosing a moving average as a way to filter the data is to minimize the integrated costs of the software implementation (ie, memory / CPU usage); otherwise, a more expensive filter can
used to improve detection accuracy. The methods represented by formulas (1) and (4) can also be implemented as a moving average over a predetermined set of samples, any parts of an oscillation cycle or multiple cycles of oscillation as the case may be. For example, a moving average using formula (1) could be calculated continuously using the most recent specific number of samples for each of the forward and backward runs such as the 5 most recent samples, 50 samples, 500 samples , or any number that is selected, from each of the races forward and backward. The number of samples can probably be based on the number of samples required by a particular washing machine platform to provide the degree of stacking at a resolution necessary for the operation of the particular platform of the washing machine. For formula (4), an average calculation in motion could also be implemented by taking a predetermined number and the sequence of the frequency difference terminations of formula (1), such as the last determinations of frequency difference 5, 10 or 15. The number of frequency difference determinations will likely be based on the number required by a particular washing machine platform to provide the degree of
stacking at a resolution necessary for the operation of the particular platform of the washing machine. An illustrative example of the use of the clutter detection during the operation of the washing machine may be useful in understanding the clutter detection within the washing operation. During a filling step in a washing cycle, the laundry stirrer 20 can be rotated through a preselected number of preliminary oscillation cycles, for example five, while in addition to the water that takes place in the washing chamber, or after of an initial filling of clothes washer 10. In this way, the clothes stirrer 20 rotates through five strokes forward and five strokes backwards while the machine controller 32 is aware of the degree of stacking using the previously described method. This can be achieved by the machine controller that receives data samples of the motor speed and the motor current from the sensor 31, which stores the values of the average frequency for each of the strokes forward and backward in the oscillation cycle, determine the frequency difference between the two average frequencies and maintain differences of the average frequencies. At the end of a cycle, the frequency difference, delta_F can be compared to a preselected threshold value T. Alternatively or additionally, you can also
make a comparison at the end of the multiple cycles, where the value can be either an average moving or not. The controller 32 of the machine uses the determination of the degree of stacking to control the operation of the laundry washer. Specifically, the controller 32 of the machine will take a corrective action to separate the heaped laundry if the difference in frequency equals or exceeds the threshold. It should be noted that other types of threshold comparisons may exist. As described, the determined value of the frequency difference can be compared with a value greater than or equal to the base. However, the threshold could be taken in such a way that the comparison can be made in a larger than the base, smaller than the base, or less than or equal to the base. The type of comparator can usually be controlled by how the threshold number can be quantified. The predetermined threshold value can represent an optimum uniform distribution level that reflects an optimal combination of cleaning effort and cleaning efficiency. An optimum level has been reached when the difference between the average frequencies or the average of the difference between the average frequencies reaches the preselected threshold value. The ability to determine or detect the degree of stacking benefits the improvement of washing performance
as actions can be taken to reduce stacking. Once you have the ability to determine the degree of stacking, one can then manipulate the wash cycle accordingly to control the degree of stacking. Controlling the level of liquid in the clothes washer is one way in which the degree of stacking can be controlled. When the liquid level increases in the wash chamber, the fabric articles can be submerged further. Even if the items are not completely submerged, the additional liquid is added to the flotation effect of the fabric items. This has an opposite effect than the weight force of the fabric articles. In some cases, the liquid may be sufficiently deep and the laundry shaker may be sufficiently agitated with the liquid so that part or all of the fabric articles do not bunch up which will greatly reduce the load of the clothes shaker 20 by the articles of cloth. This in turn allows the garment shaker to move freely and increase its speed compared to when the cloth items were piled up. This allows the controller to reduce the motor current. In this way, the determined degree of stacking can be used to adjust the liquid level and consequently control the degree of stacking. Another way to control the degree of stacking
it constitutes changing the length and speed of the forward or backward movement of the clothes stirrer in the clothes washer. First, the speed of the clothes stirrer can be controlled. Additionally, the clothes stirrer can be controlled to increase or decrease the length of the stroke forward or backward. The shorter and faster runs of the clothes stirrer can easily disintegrate from the stacked fabric items. Once the fabric articles are separated further, they can then continue to disperse more evenly in the wash chamber by the forward and backward loads of the laundry stirrer. Shorter runs can also be used in combination with the increased liquid levels in the wash chamber to reduce the amount of stacking of the fabric articles. In this way, the determined degree of stacking can be used to adjust the length and speed of the run of the clothes stirrer and consequently control the degree of stacking. In addition, the machine can also stop if it happens that the degree of stacking is high enough for safety reasons and in such a way that the damage will not be done in the machine. In addition, if the mean square difference value or the mean square difference of the moving average becomes smaller than the threshold, the addition of current to the liquid for the washing chamber is
it will stop. Or if the mean square difference value or the average root mean square motion difference becomes smaller than the threshold, runs can be lengthened and reduced in speed when necessary. The fluid level and the length of the stroke and speed settings can be carried out at any time during the wash cycle. For example, it may be part of the filling step or it may be part of the washing or rinsing steps. In this way, the fabric articles can be demagnited as soon as the stacking detection occurs. This also acts as a safety step if the fabric articles are irreparably stacked immediately when a user loads the laundry into the washing machine. The machine may stop immediately before damage to the machine occurs. The invention described herein provides an optimized wash cycle by establishing a liquid level, stroke length and stroke speed that are sufficient to satisfactorily clean a wash load, thereby causing the stacking of the laundry items. Fabric in the load. In this way, the items that are washed are cleaned more efficiently and cleaned better thereby saving costs for the customer related to the cleaning and repeated cleaning. Finally, the use of the motor current to determine aoptimum liquid level and the length of the stroke and speed does not require additional instrumentation, therefore minimizing additional cost. The invention simply uses readily available information in a new form to control an operation to optimize the washing performance of a clothes washer. While the invention has been specifically described together with certain specific embodiments thereof, it is understood that it constitutes an illustration and not a limitation. A reasonable variation and modification are possible within the scope of the foregoing description and the drawings without departing from the spirit of the invention defined in the appended claims.