EP0962576A1 - Washing machine with a device for determining the nature of the laundry - Google Patents

Abstract

The washer or washer/drier incorporates a system for calculating the quantity of water absorbed by the wash load by measuring the initial water level and the level after a set absorption time and uses a memorized table of data to determine the nature of the load and vary the washing cycle accordingly. The washer or washer/drier incorporates a system for calculating the quantity of water absorbed by the wash load by measuring the initial water level and the level after a set absorption time and uses a memorized table of data to determine the nature of the load and vary the washing cycle accordingly. The system incorporates extensometric gauges (1,2) mounted on parts of the machine supporting the load, e.g. beneath feet, on shock absorbers or the drum. The gauges supply data on the weight of the wash load and water through amplifier and filter circuits (4,5) to a computing unit (6) controlling the washing and drying cycles, and halting the drying cycle, for example, when the weight of the dried load is the same as the weight put into the machine.

Description

The present invention relates to a washing machine or a washing and drying machine with a washing device determination of the nature of the laundry. It applies in particular to top loading machines than top loading machines frontal. It applies to washing machines only or to machines which wash and dry at the same time.

It is known to control the rotation cycles of the drum a washing machine or washer / dryer depending on the nature of the laundry, with the particular aim of not damaging certain delicate fabrics. The user then initializes the washing command according to a predefined choice of types of linen. One problem is that some users do not take not take into account the nature of the laundry in the drying order, or that they don't always know how to determine it. It is therefore interesting that a machine who dries the laundry can determine the nature of the laundry. Another disadvantage of current solutions is that controlling the cycles of washing is defined only according to a few broad types of pre-established natures. It is therefore not possible to refine the order of the cycles according to a large choice of types of laundry.

Weighing laundry is also an important step in washing process of a washing machine or machine washer / dryer. Knowledge of the weight of laundry makes it possible to manage washing recipes adapted for example in duration, quantity of water and energy. It is thus possible to optimize in particular the quantity of water and the energy required for a washing phase.

Several weighing methods are known. The so-called method “Automatic variable capacity” takes into account the absorption of water by Laundry. The greater the quantity of laundry, for a given nature, for example cotton or sponge, the more water is absorbed high. It is then known to use a low differential pressure switch which makes water reminders at the start of the cycle until the laundry is perfectly soaked. If the load is very low, there is no water booster, resulting in a gain in water, then in energy to heat it. A derived method consists of shake the load well at the start of filling with a normal pressure switch higher level. The agitation of the linen notably allows absorption faster depending on the amount of laundry.

Other known methods consist in measuring the inertia of the assembly consisting of the linen and the drum by speed measurements at different times and with different acceleration ramps. The weight of the whole being thus determined, a priori knowledge of the weight of the drum lets you know that of the laundry. Electric current measurement consumed by the drum drive motor also gives a indication of the laundry load, because this current depends on the torque applied by the motor to drive the drum filled with laundry, so in fact the inertia of the whole.

The previous methods are certainly economical, but they offer little or no measurement reliability. Indeed, it is very difficult, by these methods, to distinguish better than two load levels. We actually distinguishes a low load, which is characterized by a lower weight or equal to 2.5 kg, and a heavy load, which is characterized by a weight 2.5 kg or more. In addition, it often happens that the measurement mistaken between these two load categories. This system being unreliable, we prefer in fact the heavy load to avoid the bad washing of a heavy load.

When using a pressure switch, the unreliability of the measurement comes in particular from the architecture of a machine. The measure of the pressure in the tank of a washing machine is done at a compression chamber itself connected to the bottom of the tank by a pipe. The pressure of the compressed air in the compression chamber is the picture the water level in the tank. Now this compression chamber contains usually foam which distorts pressure measurements without consequences for an approximate water level measurement, but prohibitive when it comes to deducting an amount of water absorbed. Of machines have a tank in which the compression. There is no longer any foam but the presence of waves at the interior of this room still distorts the measurements too much for a estimation of water absorption by the laundry.

This lack of reliability in measuring the load of laundry can elsewhere prove to be even more troublesome for washing / drying machines. These machines can only dry half their rated load generally equal to 5 Kg, or 2.5 Kg. The user must then remove a part of the machine's laundry after the washing phase, the laundry washed in front be dried twice. However, the user does not have a precise notion the weight of the laundry. It can therefore remove too much laundry, which results in loss of time and wasted energy. He can also leave too much, which leads to poor drying, not homogeneous and also liable to crease the laundry. If the machine is substantially filled at its expense nominal before its washing phase, there is actually a good chance that a user does not distribute the two parts of laundry well, and there is both a wasted energy, for overestimated load, and poor drying for the underestimated charge.

Furthermore, the above methods do not allow measurement than the weight of the laundry. However, for a washer / dryer or a drying machine, it is useful to know the amount of water present in the laundry throughout the washing phase, and before the drying phase. This allows in particular to optimize this drying phase by depends on the amount of water actually present in the laundry, which not allow for example a timer device determining a priori the drying time required. In this case, the laundry is still too wet at the end of the drying cycle, or too dry, at the risk of degrading it and suddenly safe at the cost of extra energy. It is known to determine the quantity of water present in the laundry by measuring the electrical resistance of the laundry. This solution requires a rotating contact for the machines washer / dryer with front opening and two rotary contacts for top loading washing / drying machines. This solution is therefore difficult to implement. Added to this are quality issues electrical contacts which must withstand very high rotational speeds high. It is also necessary to provide galvanic safety insulation because the user has access to the basket. Rotary contacts connected to a device measurement electronics must therefore be isolated from the 230 Volt sector. Of the more the measurement is not perfect because the resistance of the linen varies in particular with the water used and detergents such as for example fabric softeners or detergents. There are therefore dispersions.

It is still possible in particular to limit the duration strictly necessary for drying, stop drying as soon as the amount of water detected in the laundry has become substantially zero. He is certainly known use humidity sensors, drying being interrupted when these sensors give information corresponding to a dry cloth. However in this case, we do not directly measure the amount of water contained in the laundry, but the humidity. It is therefore necessary to use calibrations and complex algorithms to implement and a reliability that remains limited.

There are also methods for detecting imbalances in the drum filled with linen. The advantage of the unbalance measurement is to highlight poor distribution of laundry inside the drum which can result in a lower quality spin and very heavy loads important of the structure. When an imbalance is detected, the drum for example several turns in one direction, then several turns in the other sense at sufficient speed to distribute the laundry and remove the imbalance. Of known imbalance detection methods are based on the variation of basket speed in acceleration or knowledge of the current supply of the drum drive motor. These various solutions are satisfactory for the detection of imbalance but do not allow the drum yaw detection. However, the existence of a lace corresponds to a significantly unevenly distributed load of laundry on both sides of the symmetry of the drum perpendicular to its axis of rotation. This asymmetry can cause lateral movements of the tank of the machine. Side shocks are then possible between this tank and the machine casing during the spinning phases.

An object of the invention is in particular to allow the determination automatic nature of the linen introduced into a drying machine laundry or washing and drying the laundry. To this end the invention relates to a washing machine, characterized in that it includes gauges of extensometry and calculation means, the extensometry gauges being placed on parts of the machine that support the laundry, such so that the gauges deliver measurement signals depending on the weight of these elements, the calculation means determining the weight of the laundry in making the difference between the measurement provided by the gauges of extensometry and the weight of the memorized elements.

The main advantages of the invention are that it allows the machine to adapt to a wide variety of laundry types, whether it allows a reliable measurement of the weight of the laundry introduced into a machine, that it determines the amount of water present in the laundry during the drying phase, that it optimizes the phases of washing and drying, in water, time and energy, which it allows determine the yaw of a drum, which it determines the resonance of a machine, that it is simple and economical to implement, in the especially measure where it allows to perform several functions essential with the same components or possibly some additional components.

• la figure 1, une illustration de la détermination de la quantité d'eau absorbée par le linge dans une machine selon l'invention, selon plusieurs courbes fonction de la nature du linge ;
• la figure 2, par un synoptique, une machine à laver selon l'invention ;
• les figures 3, 4 et 5, des exemples de dispositions de jauges d'extensométrie dans une machine à laver selon l'invention ;
• la figure 6, une illustration du taux d'essorage en fonction du temps.

Other characteristics and advantages of the invention will become apparent with the aid of the description which follows given with reference to the appended drawings which represent:

• Figure 1, an illustration of the determination of the amount of water absorbed by the laundry in a machine according to the invention, according to several curves depending on the nature of the laundry;
• Figure 2, a block diagram, a washing machine according to the invention;
• Figures 3, 4 and 5, examples of arrangements of strain gauges in a washing machine according to the invention;
• Figure 6, an illustration of the spin rate versus time.

According to the invention, from a dry measurement of the linen introduced in a machine, before washing, it is possible to define the nature of the linen introduced into this machine. By equipping, for example, the machine with pressure sensor in the tank, the invention makes it possible to determine this nature. This sensor measures the level of water in the tank, while other means of measuring the water level that can be used. The washing machines are generally equipped to allow precisely control of the tank water level. Pressure can thus be measured by means of a compression chamber connected for example to the tank by a pipe. The pressure in the compression chamber is the image pressure in the tank and as a corollary the image of the water level in the tank. Measuring the pressure in the compression chamber can be performed by a pressure switch. A saved conversion table gives the correspondence between the measurements made by the pressure switch and the water level in the tank. The nature of the laundry is defined by its water absorption. A memorized table can indeed give the correspondence between the amount of water absorbed by the laundry and the weight of the dry laundry on the one hand, and the nature of the laundry on the other. Figure 1 illustrates the determination of the amount of water absorbed by the laundry.

To this end, Figure 1 shows several curves 51, 52, 53 representative of the amount of water absorbed by the linen according to its nature. The N level of water in the tank is shown along the ordinate axis. The time t is represented along the abscissa axis. Up to a time t ₀ , the tank is filled to its nominal level N ₀ . Then, depending on the nature of the laundry, the water level drops to an asymptote parallel to the abscissa axis, the level of which depends on the nature of the laundry, for a given quantity of laundry, therefore a given laundry weight. This asymptotic level is obtained from a time t absorption _gave. The difference Δ _N between the nominal level and the final level of an asymptote indicates the amount of water absorbed by the laundry. The nominal and final levels are for example determined by means of the pressure sensor in the tank. The values of these levels are for example supplied to calculation means, by means of representative signals developed in a known manner. Knowing the quantity of water absorbed by the laundry as well as the dry weight of the latter, these calculation means can then deduce the nature of the laundry by means of the aforementioned table. The table obviously does not contain all the possible values of quantities of water and weight of laundry. It nevertheless contains discrete values, the difference between two successive values is small enough to provide sufficient reliability on the nature of the laundry, while treating a wide variety of types of laundry. The table is for example a table with two series of entries, a series of entries for the quantity of water absorbed and a series of entries for the weight of dry laundry. It includes a series of outputs which are the types of linen. The calculation means knowing a quantity of water absorbed and a weight of dry laundry, for example define the discrete input values of the table as close as possible. This table then gives the quantity of laundry from the input values retained by the calculation means.

Knowledge of the nature of the linen improves the economic and energy performance of washing. She permits including improving the quality. The duration of the washing cycle and its characteristics can be exactly, or almost, adapted to the type of laundry. The same is true for the drying cycle, which can also take into account the nature of the laundry. The means of calculation provide information on the nature of the laundry to the cycle cycle control means washing and / or drying.

Figure 2 shows, by a block diagram, a machine comprising at least one strain gauge to allow the measurement of laundry to dry. Figure 2 shows an example with two gauges 1, 2. These gauges are placed on elements of the machine that supports loaded laundry. The gauges are for example part each of a complete bridge with three resistors R1, R2, R3, powered by a DC voltage 3, for example rectified from alternating current of the supply network by known means not shown. A deformation of the element on which a gauge is placed modifies the electrical resistance of the latter so that the output voltage of the corresponding bridge is modified. A correspondence table is carried out to determine the weight of the element on which a gauge from the latter's deformations, and therefore in particular as a function of the bridge output voltage. This output voltage is by example shaped by means 4, 5 comprising for example amplification and filter circuits. Tensions, images of deformation of the element on which the gauges are placed, are taken into account, by example via the formatting means 4, 5 by calculation means 6. These calculation means are, for example, those used for determining the nature of the laundry. They include for example the tables of correspondence giving the weight of the element (s) supporting the gauges as a function of the deformations of these gauges, more precisely as a function voltages supplied for example by complete bridges. In addition, calculation means 6 have in memory the weight of one or more elements supporting the laundry, in the absence thereof, that is to say the actual weight of these elements. By making the difference between the measured weight, by through gauges 1, 2, in the presence of laundry, and the actual weight, stored, elements supporting the laundry, the calculation means determine the weight of the laundry, which is the result of this difference.

Figure 3 illustrates, in a partial and schematic view, a example of arrangement of strain gauges 21, 22, 23, 24 in a washing machine 25. In this example, the strain gauges are located under the machine feet. In this case, the whole machine is weighing. The means of calculation, knowing in memory, the weight of the machine, can then determine the weight of the loaded laundry. The figure 2 illustrates a case of using four strain gauges. It is possible also to use only two, for example two at the front, 21, 22, or two at the rear 23, 24. In this case, an economy of realization is then carried out, possibly however at the cost of less precision. It is still possible to provide an embodiment with two gauges 21, 22 at the front, and a single strain gauge at the rear, but centered, this situation can be reversed by placing the two gauges at the back.

Figure 4 illustrates, in a partial and schematic view, another possible embodiment of a machine according to the invention, with regard to particularly concerns the arrangement of strain gauges. Figure 3 shows the tank 31 of a washing machine and one of its dampers 32. These last, located between the tank 31 and the machine casing, allow particular to the tank to absorb the mechanical shocks to which it is subject. In this embodiment, the strain gauges 1 are by example located under the shock absorbers 32, between the latter and the bottom of the carcass 33 of the machine. The elements supporting the laundry include in this case the shock absorbers 32, the tank 31, the drum and the ballast, these last two elements not being shown. The gauges measure the weight of these items and the laundry in the drum. The weight of the laundry is determined by the calculation means in subtracting from the total weight measured by the gauges, the weight of the elements mentioned above stored by the calculation means 6.

Figure 5 shows another embodiment where the gauges of extensometry 1 are placed on the axis 41 of the drum 42. A gauge is placed on each side of the drum, for example at the bearings to marbles. These strain gauges then measure the drum 42 filled with linen. Knowledge of the weight of the drum by calculation means 6 allows the latter to determine the weight of the laundry.

In combination with the washing cycle control means and possibly drying, the calculation means 6 can determine the weight of dry laundry, but also the amount of water contained in this laundry. Thus, the calculation means 6, which are for example integrated into the circuits machine controls, determine the weight of the laundry before filling the tank with water. It is the determination of the weight of the laundry dry. From this information, the quantity of water strictly necessary for washing can be set. The washing cycle control means, not represented, therefore take this information into account to define optimally the amount of water needed for washing and the duration of this latest. For this purpose, a memorized table indicates according to the quantity of laundry, cycle times and the amount of water associated. This results in a saving water, but also saving time and energy.

After spinning, the laundry weight measurements made by the strain gauges and the means of calculation actually give the weight of the laundry and the amount of water it contains. Calculation means 6 having memorized the weight of the dry laundry, they can deduce the weight of the quantity of water, and therefore by knowing the density of water, the amount of water in the laundry. The means of calculation determine the amount of water at a given time by the difference between the current measurement the weight of laundry at this time and the weight of dry laundry, memorized. So if the washing machine is also drying, it is possible to stop drying as soon as the weight of laundry detected corresponds to the weight of dry laundry, i.e. the amount of water in the laundry is zero or substantially zero. The drying time can thus be optimized. Information on the quantity of water is then for example provided by the means calculation 6 to the control means of the drying phase not represented. The calculation means send for example a signal when the weight of laundry measured is approximately equal to the weight of dry laundry, for that the drying control means notably stop the cycle. This determination of the humidity level of the laundry can still obviously be used for drying machines only.

Washing / drying machines can only dry half the nominal laundry load. It may happen that a user only loads his machine at half the rated load without the know. The conditions to chain the automatic drying are therefore filled, without the need to remove part of the washed load. According to the invention, a load display indicates the weight of the laundry present in the machine. This display could for example be visible on the open door of top loading washing machine or dryer. This display is connected by known interfaces to the calculation means 6 who deliver the weight of laundry measured. These deliver the weight continuously measured so that the user can see as as it loads the laundry into the machine, the weight of laundry loaded, a loading limit, for drying, being displayed elsewhere for the user. The drying control means follow automatically the drying phase after washing if the displayed weight is less than or equal to a given threshold, i.e. in fact the loading limit previous, for example half the nominal load of the machine. Through example, if the user does not take it into account, the control means of the drying cycle, also connected to the calculation means which deliver the weight of laundry, do not automatically sequence the drying cycle, but wait for the user to remove laundry from the machine to go into below the maximum load limit for drying. This limit can hold account of the nature of the linen. In this case, the control means of the drying phase take into account for example the indication given by the user via the programmer, for example cotton, synthetic, blend, etc ... These means can still take into account the nature of the textile as defined above from the absorption of water by the laundry. Of even, the limit value displayed for the user can take into account the nature of the laundry introduced into the machine.

For a washing machine, the invention also saves time during the spin phase. This advantage is illustrated in FIG. 6. This figure shows a curve 61 representative of the spinning rate of the laundry Te as a function of time t. The duration of the spin phase is generally predetermined up to a time t _f when it is certain to have reached the final spin rate Te _f . However, this final spin rate can be reached well before the predetermined time t _f , in fact at a time t _f - Δt _i . The additional spin duration Δt _i is therefore unnecessary. It is a waste of time, but also of energy. The spin rate Te is given by the following relationship: Te = Ch (dry laundry) + Qeau Ch (dry laundry) where Ch (dry laundry) represents the load of dry laundry and Qeau represents the amount of water.

The final spin rate Te _f is therefore given by the following relation: You f = Ch (dry laundry) + Qeau r Ch (dry laundry)

Qeau _r being the quantity of residual water corresponding to the final spin rate. This quantity of water is then defined by the following relation: Qeau r = Ch (dry laundry) [Te f - 1]

Te _f being predefined, Te _f - 1 can then be memorized by the calculation means of the machine. The load of dry laundry having been determined before the washing phase and then stored by these calculation means, as soon as they measure a quantity of water less than or equal to the value Q water _r as defined by relation (3) previous, for example they send information to the means for controlling the washing phase, which in particular control the spinning phase. On receipt of this information, these means stop the spin. The amount of residual water in the laundry is defined in particular as explained above, by difference between the weight of wet laundry measured and the weight of dry laundry. By notably noting Pv the density of water, the quantity of residual water in the laundry is then obtained according to the following relationship: Qeau r = P wet laundry - P dry laundry P v where P _{wet linen} and P _{dry linen} represent respectively the weight of wet linen and the weight of dry linen.

The weight of laundry measured during the spinning phase being in fact the weight of wet laundry, the calculation means recognize that the final spin rate is reached when the weight of wet laundry responds to the following relationship, by combining the relationships (3) and (4): P wet laundry = Te f × P dry laundry

The calculation means then send to the control means of the washing phase, a signal indicating that the final spin rate is achieved.

The invention also makes it possible to easily detect unbalances in the drum but also the laces. Regarding unbalances, several detection methods are known. They are generally based on the variation of drum speed during acceleration or current measurement of the latter's drive motor. These solutions are satisfactory, but they do not make it possible to determine the yaw of the drum. A lace important can cause significant lateral displacements of the drum and tank. Such a yaw does not cause a speed variation of the drum, or variation of the current of the drive motor of the latter. Extensometry gauges, located for example under the shock absorbers in accordance with the arrangement of Figure 3 allow in particular to determine the movements of the tank, more specifically the difference vertical displacements between the two sides of the tank, and therefore the laces. A maximum allowable yaw is for example defined in relation to maximum displacement deviation between strain gauges arranged on each side of the tank. Information relating to extension gauges are delivered as electrical signals to means of calculation. The latter can therefore include a program of verification of the differences between the different signals received. So an imbalance and / or a maximum admissible yaw being defined in relation to a deviation of signal between strain gauges 1, 2, 21, 22; 23, 24 arranged on each side of the tank, information relating to the extension of the gauges are delivered in the form of electrical signals to the calculation means 6, the latter including a program for verifying the differences between the different signals received.

The invention also makes it possible to detect the resonant frequency of the machine in the spin phase. Depending on the load of laundry, the distribution of this laundry in the drum and the speed of rotation of the drum, it can produce a particular resonance. The strain gauges are also sensitive to vibrations, which can detect a level of vibration not acceptable, corresponding to a resonant frequency. When there are vibrations, the gauges undergo repeated extensions, which results in an oscillatory signal supplied to the calculation means. These the latter can then run a verification program of the frequency of received signals. If a vibration level is detected not acceptable, i.e. when the frequency of the signals received exceeds a given threshold, the calculation means send for example a information to the control means of the spinning phase so that they control a change in spin speed, in order to exit the regime of resonance. So, if for example the user has programmed a speed of spinning 600 rpm, the phase control means spin can then control a speed of 650 rpm.

The invention therefore shows all its effectiveness, since to the extent the weight of the laundry itself, it allows the realization of functions of primary importance, without significantly complicating the Implementation. In particular, the additional functions do not require an additional software adaptation, and possibly some additional interfaces or components, generally at low cost, to the extent where the strain gauges are the foundation for achieving most of these functions.

Finally, the invention shows that it makes it possible to improve the energy performance of all types of washing machines, drying machines or washing and drying machines. In particular it saves water, in particular by allowing to use the quantity of water strictly necessary by an acquaintance exact weight of dry laundry. It also saves time and energy, by a permanent knowledge of the quantity of water present in the laundry throughout the washing cycle and / or the drying.

Claims (18)

Washing machine or washing and drying machine, characterized in which, comprising means for measuring the water level, means for calculation define the amount of water absorbed by the laundry by difference of water level initially filled and the water level reached from a given absorption time, a memorized table giving the correspondence between the amount of water absorbed by the laundry and the weight of the dry laundry of a on the other hand, and the nature of the laundry. Machine according to claim 1, characterized in that the calculating means (6) provide information on the nature of the linen to the means for controlling the washing and / or drying cycle. Machine according to any one of the claims previous, characterized in that it includes gauges extensometry (1, 2, 21, 22, 23, 24) and calculation means (6), the gauges of extensometry being placed on elements (25, 31, 32, 41, 42) of the machine that supports the laundry, so that the gauges deliver measurement signals depending on the weight of these elements, the means of calculation determining the weight of dry laundry before the washing cycle by performing the difference between the measurement provided by the strain gauges and the weight memorized items. Machine according to claim 3, characterized in that the strain gauges (21, 22, 23, 24) are arranged under his feet, the weight of the machine (25) being stored as an element supporting the laundry. Machine according to any one of claims 3 and 4, characterized in that the strain gauges (1) are placed under the shock absorbers (32), the elements supporting the laundry comprising the shock absorbers (32), the tank (31), the drum and the ballasting devices. Machine according to any one of claims 3 to 5, characterized in that the strain gauges (1) are placed on the axis (41) of the drum (42), on each side of the latter, the element supporting the laundry being the drum. Machine according to any one of the claims above, characterized in that the calculation means (6) determine the amount of water in the laundry, by difference between the measurement current laundry weight and the stored dry laundry weight measurement. Machine according to claim 7, characterized in that the water quantity information is supplied to the control means of the drying phase. Machine according to claim 8, characterized in that the calculation means (6) send a signal when the measured laundry weight is substantially equal to the weight of dry laundry, so that the means of drying control stop the cycle. Machine according to any one of the claims previous, characterized in that it comprises a display, connected to the calculation means (6), which indicates the weight of laundry loaded in the machine. Machine according to claim 10, characterized in that the machine being top-loading, the display is visible when the machine door is open. Machine according to any one of claims 10 or 11, characterized in that the machine being washing and drying, the means of drying control automatically follow the drying phase after washing if the displayed weight is less than or equal to a given threshold. Machine according to claim 12, characterized in that the given threshold depends on the nature of the laundry. Machine according to claim 12, characterized in that the given threshold is half the nominal weight of laundry for the machine. Machine according to any one of the preceding claims, characterized in that when the calculation means determine a weight of wet _laundry P _{wet laundry} verifying: P wet laundry = Te f × P dry laundry where Te _f is the final spin rate and P _{dry laundry} is the weight of dry laundry, they send a signal to the control means of the spin phase indicating that the final spin rate has been reached. Machine according to one of the preceding claims, characterized in that a maximum allowable unbalance and / or yaw being defined in relation to a signal gap between the gauges extensometry (1, 2, 21, 22; 23, 24) arranged on each side of the tank, the information relating to the extension of the gauges is delivered in the form electrical signals to the calculation means (6), the latter comprising a program for checking the differences between the different signals received. Machine according to any one of the claims above, characterized in that the calculation means include a program to check the frequency of signals received from strain gauges (1, 2, 21, 22; 23, 24). Machine according to claim 17, characterized in that when a measured frequency is equal to a known value of the control as being a resonant frequency of the structure of the machine, the calculating means (6) send a signal to the means of spin phase control to change the rotation speed of the drum.

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