ES2363817T3 - APPLIANCES FOR THE TREATMENT OF TEXTILE MATERIALS WITH DISPLACEMENT SENSOR. - Google Patents

Abstract

The present invention relates to a household appliance for treating soft goods, in particular a laundry washing machine, comprising a swinging assembly elastically constrained to a frame by means of a suspension system comprising a pair of elements telescopically coupled together through two respective ends, wherein the first of said two ends comprises ferromagnetic material and the second end comprises a coil (9). The household appliance also comprises an electronic detection module (6) comprising an oscillator circuit (12), the oscillation frequency of which depends on the impedance of the coil (9), and processing means operationally connected to the oscillator circuit (12) and adapted to measure the oscillation frequency and to determine, as a function of said oscillation frequency, at least one piece of information which can be associated with said relative displacement.

Description

The present invention relates to an appliance for the treatment of textile materials according to the preamble of claim 1.

In particular, the present invention relates to domestic machines for washing clothes.

The term "laundry machine" is used herein to indicate a machine suitable for at least one washing treatment on textile materials. A machine for washing clothes can be a so-called "washing machine" (intended only for washing) or a so-called "washing machine / dryer machine", which can also perform a drying process of textile materials (in particular, by hot air blown towards the casting tank by means of a blowing system).

The known appliances for the treatment of textile materials comprise an oscillating assembly in which the elements to be treated are loaded. The oscillating assembly is elastically fixed against a structure by means of a suspension system.

In machines for washing clothes, the oscillating assembly comprises a tank, in which the textile materials are washed.

Textile materials can be loaded from the front, through an opening made in the front wall of the machine, or from the top, through an opening made in the upper wall of the machine.

Various types of sensor devices for household appliances are available on the market to determine the relative displacement of the oscillating assembly with respect to the structure of the appliance, in order to detect, for example, the mass or weight of the clothes present inside of the appliance and / or the value of any load imbalance during operation of the appliance and / or the amount of rinse water supplied to the tank.

Such sensing devices are often arranged in one of the mechanical elements of the appliance.

If the appliance is a machine for washing clothes, the sensing devices used to determine the relative displacement of the oscillating assembly with respect to the structure of the appliance can be suitably arranged in one of the dampers that are in the appliance's suspension system. In that case, the relative displacement between the piston and the shock absorber cylinder is used to detect the relative displacement of the oscillating assembly with respect to the structure. It should be noted that the terms commonly used "cylinder" and "piston" refer respectively to the outer and inner elements of a shock absorber, which adapt to a telescopic displacement.

The DE 4319614 patent describes a machine for washing the front loading laundry washing machine with an oscillating assembly suspended in two spring elements and connected the structure by means of two dampers. In one of the two dampers a Hall effect sensor device is installed in the piston and a permanent magnet is arranged in the cylinder. The relative displacement between the cylinder and the piston thus translates into the corresponding relative displacement between the magnet and the Hall sensor, such that the output of the latter is a voltage value that is proportional to said relative displacement.

This solution has the disadvantage that an accurate reading of the displacement requires the use of very expensive permanent magnets (of the lanthanide type). Likewise, these sensors do not allow a very precise detection, since the small relative displacements between the piston and the cylinder translate into imperceptible variations in the amplitude of the voltage signal. The detection of these movements requires very expensive electronics, which are rarely available in household appliances for the treatment of textile materials.

Patents EP1220961 and EP1094239 disclose a shock absorber for a machine for washing clothes, in which a coil is applied to one of the two mobile elements (cylinder and piston), while a ferromagnetic element is applied to the other element which can affect the inductance value of the coil depending on its position in the latter. When alternating current having a predetermined amplitude is applied to the coil, the amplitude of the voltage across the coil is proportional to the relative displacement between the cylinder and the piston of the damper. By reading the amplitude of the voltage in the coil it is therefore possible to obtain the relative displacement value.

Although to a lesser extent than the solution, in which a Hall sensor is used, this solution also suffers from some limitations that affect the detection of displacement, which are related to the ability of the electronics to detect small voltage variations.

According to both solutions described above, in fact, the determination of the relative displacement between the piston and the cylinder of the shock absorber translates into a direct voltage that is obtained by processing, by means of a suitable electronic circuit, the signal generated by the associated sensor, the latter being a Hall effect sensor or a coil, respectively.

The worst drawback of this procedure is that the electronic circuit used to process the signal generated by the displacement sensor is of the analog type and, therefore, is characterized by the limitations of said technology, which are a consequence of both the tolerances and the thermal drifts of its elements as a low immunity to electrical noise. Therefore, such a solution turns out to be very expensive, since it implies that it is necessary to use elements of a higher quality characterized by very strict tolerances and a low thermal drift.

Solutions known in the art, in which an analog signal is transmitted, also require the presence of electromagnetic shielding systems capable of preventing readings from being affected by electromagnetic noise.

An analog electrical circuit that can be used in the signal processing generated by a displacement sensor based on a coil and a ferromagnetic element, arranged respectively in two movable elements of a damper for a laundry machine, is described, by example, in patent EP654140.

The objective of the present invention is to overcome the above mentioned limitations of the prior art.

In particular, an objective of the present invention is to provide a solution, preferably a low cost one, to accurately determine the relative displacement between two telescopically coupled elements (in particular, the cylinder and the piston of a damper) of a suspension system. of an appliance for the treatment of textile materials.

These and other objectives of the present invention are achieved by an appliance that incorporates the characteristics set forth in the appended claims, which are intended to be part of the present description.

The present invention is based on the general idea of providing an electronic module comprising an oscillator circuit, whose frequency of oscillation depends on the impedance of a coil disposed in one of the two elements telescopically coupled.

The relative displacement between the two elements (coinciding with the relative displacement between the oscillating assembly and the structure of the appliance) is thus determined by an electronic detection module based on the oscillation frequency of said oscillator circuit, which is determined, for example, by a microcontroller comprised in said electronic module. The relative displacement S is therefore determined by taking advantage of the fact that the value of the coil inductance L depends on the axial penetration x of one of the two elements in the volume of the coil itself. As a result, the value of the frequency f of the signal, preferably a square wave signal, generated by the oscillator circuit (which incorporates the coil) depends on said value of the inductance L and, therefore, is related to said relative displacement S.

Advantageously, in addition to determining the relative displacement S of the two mobile elements, the present invention also provides the determination of one or more quantities associated with said relative displacement S (such as, for example, the weight of the textile materials found in the drum of the washing machine and / or the amount of water supplied to the tank and / or the imbalance of the laundry load) determining the value of the frequency instead of the value of the amplitude of the voltage as in the prior art. Advantageously, a microcontroller comprised in the electronic module according to the present invention processes the output signal locally by means of the oscillator circuit to obtain, based on its frequency f, the relative displacement value S between the two elements and / or of any other physical quantity. associated with said relative displacement S (such as the weight of the laundry arranged in the drum of the washing machine or washer / dryer): in the present embodiment, the microcontroller sends the result of said processing to the electronic control system of the appliance in a suitable digital communication line. According to an advantageous embodiment of the present invention, which aims to ensure greater measurement accuracy and reliability over time, said local processing may take into account one or more external interference factors that impair the quality of the displacement reading. relative S.

The appliance according to the present invention will become apparent, together with its additional advantages, from the following detailed description and the accompanying drawings, which are provided by way of non-limiting example, in which:

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Figure 1 is a sectional view of a shock absorber of an appliance according to a first embodiment of the present invention;

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Figure 2a is a functional scheme of an electronic detection module known in the art, which is used to detect the relative displacement between the cylinder and the piston of a damper of a laundry machine by determining the variation in voltage amplitude. through a coil disposed in the cylinder of the shock absorber;

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Figure 2b is a functional scheme of an electronic detection module according to the present invention, which is adapted to detect the relative displacement between the cylinder and the piston of a damper of a machine for washing clothes by frequency determinations;

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Figure 3 is an overall view of a damper, an electronic detection module and an electronic control system of an appliance according to the present invention;

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Figure 4 is a sectional view of a shock absorber of an appliance according to a second embodiment of the present invention.

In the following description, reference will be made to a machine for washing clothes from a preferred, but not limiting example of application of the present invention.

Figure 1 represents a shock absorber 1 comprised in the suspension system of a machine for washing clothes according to the present invention.

Said laundry machine, which can be a washer or washer / dryer machine, comprises a structure and an oscillating assembly, the latter comprising a drum adapted to accommodate textile materials to be treated and rotated on its axis by means of a device of motor, and a tank adapted to contain the water or the detergent used to carry out the treatment. A suspension system connects the oscillating assembly with the structure while maintaining it suspended elastically. Said appliance also comprises an electronic control system with a central controller and possibly an interface device capable of providing information to the user of the appliance. Said interface device may be a luminous device, for example, an electronic display or an array of LEDs, or an acoustic device, for example, a bell or voice synthesizer.

To improve the operation of the machine for washing clothes, it is useful to determine the relative displacement between the oscillating assembly and the structure. In fact, said determination allows, under static conditions, to know some characteristics of the load that is present in the appliance, while in dynamic conditions it allows quantifying the imbalance of the load inside the drum and / or the vibration of the oscillating assembly, or determine the maximum allowable spin speed. Particularly interesting is the possibility of using the relative displacement of the oscillating assembly with respect to the structure under static conditions to obtain the mass or weight of the clothes that are in the drum, preferably the mass or the weight of the clothes loaded in the drum by the user before starting a wash treatment.

A laundry machine, which is the objective of the present invention, comprises, in its suspension system, shock absorbers attached to the oscillating assembly (i.e., the tank assembly) by means of a top fixing and to the structure by a lower fixing articulated to a pin. The dampers perform a very important function damping the oscillations of the oscillating assembly, mainly during the centrifugation phases. Said dampers comprise a cylinder, that is, a cylindrical tubular element, in which a piston slides, which is usually also a cylindrical tubular element, and is braked by a brake element that can generate proper friction between the outer surface of the piston and the inner surface of the cylinder.

The shock absorber shown in Figure 1, which is suitable for installation in an appliance according to the present invention, comprises two elements (the piston 4 and the cylinder 3) joined together telescopically by two ends. Said elements are capable of reciprocating, in particular, the first element is capable of sliding relative to the second element in a substantially straight direction. Both the piston 4 and the cylinder 3 preferably have an axially symmetrical shape, in particular a cylindrical shape, and both are preferably hollow.

A brake element 5, preferably made of a material having a high coefficient of friction, is fixed against one of the two elements of the shock absorber 1 (for example, the cylinder 3), to come into contact with the other element (for example , the piston 4), thereby counteracting the relative sliding between the two elements.

The seats 10A and 10B are made at the ends of the shock absorber 1 for the upper and lower fasteners of the shock absorber 1.

A coil 9, comprising a cable made of an electroconductive material, is coaxially wound around the cylinder 3 along a length P, such that an end of the piston 4, made at least partially of ferromagnetic material and which is axially slides in the cylinder 3 under the effect, for example, of the weight of the laundry loaded in the drum of the washing machine, alters the magnetic field flow generated by the coil 9, when the alternating current flows through it, changing thus the value of the inductance L of the coil 9 as a function of the penetration x of the piston 4 in the cylinder 3, the correlation between the inductance L and the penetration x being expressed by a linear or nonlinear mathematical expression.

An electronic detection module 6, electrically connected to the coil 9 by the wiring 8, is fixed against the cylinder 3 by a head 13 fixed to the cylinder 3 with the screws 7A and 7B. The electronic detection module 6 is electrically connected to the central controller of the appliance via wiring 14 (which can also act as a digital communication line). In the preferred embodiment, the electronic detection module is powered by the central controller. The wiring 14 can present its welded cables to the electronic module 6 or, according to a technically equivalent solution, you can use a suitable connector in the electronic module 6, which allows the electrical cables connecting the electronic module 6 to the central controller to be connected. Figure 2a represents a schematic diagram of an analog electrical circuit, known in the art because it is described in detail, for example, in EP654140, whereby the relative displacement value between the two moving elements (cylinder and piston) of a damper of a machine for washing clothes, properly processing the voltage signal detected along the impedance coil Z3, whose inductance L depends on the relative displacement between the cylinder and the piston. For this purpose, the coil is arranged, by means of a generator G, with a sinusoidal alternating voltage of Vac frequency having a fixed frequency f0 by means of two impedances Z1 and Z2 in series, which for the sake of simplicity it is assumed herein that they are simply resistive, so that the current Iac = Vac / (Z1 + Z2 + Z3) flows through the coil. As the value of the inductance L of the coil changes, its impedance Z3 also changes according to the known ratio Z3 = R + jω0L (in which ω0 = 2πf0), as well as the decrease in voltage V3 to along its terminals. The sinusoidal signal V3, which has a fixed frequency f0, is read by a special analog detection module AM which, by means of the AC-DC suitable analog conversion, performing the filter and scale adjustment stages in the output signal, transforms the latter in a direct signal Vdc, whose value depends on the value of the coil inductance L and, therefore, also on the relative position of the two moving elements of the damper, which depends on said inductance L. In summary, the known procedure that is commonly used to determine the variations of the inductance of the coil L is characterized by the following three steps:

1) application of a sinusoidal voltage Vac, once the amplitude and frequency f0 are known, to an electrical circuit comprising a series of impedances, among which the impedance Z3 of the coil with inductance L, which changes depending on the relative displacement of the two moving elements of the shock absorber;

2) determination of the decrease in voltage V3 at the coil terminals;

3) analog processing of the sinusoidal signal V3 and generation of the direct voltage output signal Vdc, which represent the relative displacement of the two moving elements of the damper.

Figure 2b represents a schematic diagram of an electrical circuit according to the present invention, whereby it is possible to obtain the value of the relative displacement between the cylinder S 3 and the piston 4 of the damper 1 of a laundry machine. The circuit diagram of Figure 2b is based on a new procedure for detecting the displacement S provided as an alternative to that known in the art and is characterized by the following steps:

1) use of an oscillator circuit, preferably of the square wave type (for example, a "non-stable multivibrator"), whose oscillation frequency f depends on the value of the coil inductance L;

2) determination of the oscillation frequency of said oscillator circuit;

3) determination of the relative displacement S of the two moving elements based on said oscillation frequency.

Using a non-stable multivibrator or an equivalent oscillator circuit, the displacement determination is performed in a fully digital way by the following steps:

a) digital measurement of the frequency f of the square wave signal generated by said oscillator circuit, carried out by means of a suitable CNT input of an MC microcontroller;

b) digital transformation of the frequency value f read by means of the MC microcontroller and generation of a digital data representative of the relative displacement S of the two moving elements of the damper.

Of course, the measurement of the oscillation frequency also makes it possible to determine any other physical quantity related to the relative displacement S.

In the procedure known in the art (Figure 2a), a sinusoidal signal with a constant frequency f0 is passed through the voltage generator G and the decrease in voltage V3 through the coil terminals is determined; The method according to the present invention (Figure 2b), on the other hand, does not use a fixed frequency voltage generator, but a stable oscillator OSC with square wave signal and variable frequency f, the frequency f depending on the inductance value of the coil L and the frequency f is determined digitally.

It follows that said two procedures, although referring to the same shock absorber architecture intended for use in a washer or in a washer-dryer machine, such as that shown in Figure 1, detect the value of relative displacement between two moving elements of the shock absorber measuring two completely different magnitudes: a sinusoidal voltage V3 in the first case and a frequency f in the latter case.

Furthermore, if we consider the preferred embodiment of the present invention, which uses a non-stable multivibrator, the measured quantity is processed in a purely analogical way in the first case, while it is processed in a totally digital way in the latter case. The use of digital processing techniques allows to reduce the cost of the solution according to the present invention: all measurements, calibration and data processing operations can be performed using a low cost MC microcontroller (for example, a commercial microcontroller of 8 sideburns, which typically costs approximately $ 0.4 to $ 0.5).

An additional advantage of the solution according to the present invention is that the electronic detection module 6 can provide the central controller of the appliance, directly and in digital format (for example, on a serial channel), the quantity value (for example , the weight of the laundry loaded on the drum of the washing machine) associated with the relative displacement S of the two moving elements of the shock absorber. On the other hand, the output of the data by means of the analogue detection module AM in the known solutions (Figure 2a) cannot be used directly by the microcontroller: the output variable, which comprises the voltage Vdc, must be subsequently converted to the digital format and process by means of the control system of the appliance in order to obtain the value of the intended quantity (for example, the weight of the laundry loaded in the drum of the appliance).

A more detailed analysis of the present invention will be provided below with reference to Figure 3, which schematically represents the following:

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a possible embodiment of the electronic detection module 6 according to the present invention,

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the coil 9, located in the shock absorber 1 of the appliance and is used to determine the relative displacement capacity S between the cylinder 3 and the piston 4 of the shock absorber 1, and

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the serial connection, schematically represented by wiring 14, with the electronic control system, in particular, with the central controller 17 of the appliance.

The piston 4 is represented with a continuous line in a first position and with a dotted line in a second position, said first position being the position of the piston 4 before a relative displacement S occurs with respect to the cylinder 3 (and, therefore, with respect to the coil 9, which forms a part with the cylinder 3), and said second position being the position of the piston 4 once a relative displacement has occurred S.

The value of the relative displacement S between the piston 4 and the cylinder 3 is determined by the difference between the initial value x0 of the axial penetration of the piston 4 in the inner volume of the coil 9 and the final value x1 of the axial penetration of the piston 4 on the inner volume of the coil 9. xs and xi indicate, respectively, the upper and lower fill limits of the inner volume of the coil 9, where xs -xi = P.

As shown in Figure 3, the coil 9 is electrically connected (via wiring 8) to an oscillator circuit 12 and determines, depending on its inductance value L, the oscillation frequency f of the alternating signal generated by said oscillator circuit 12. The value of said frequency f can therefore be expressed by a mathematical function such as f = F (L), in which the inductance L is an independent variable. In the example of FIG. 3, the alternating signal generated by the oscillator circuit 12 comprises a square wave that has a voltage oscillation between a low voltage level (associated with logic level 0) and a high voltage level (associated with logical level 1). The signal generated by the oscillator circuit is sent to a digital input of the microcontroller 16 which, by means of a suitable CNT digital counter, determines the number of oscillations per second of the signal, that is, determines the oscillation frequency f of the oscillator circuit 12. Based on the reading of the frequency value f, the microcontroller 16 calculates the relative displacement S of the piston 4 with respect to the cylinder 3 of the damper 1 and, thus also, for example, the weight of the drum contents of the washing machine. The relationship between the value of the oscillator frequency and the weight of the clothes present in the drum of the washing machine is determined experimentally and can be expressed by a mathematical algorithm or data tables managed by the microcontroller control program 16.

The appliance intended for the treatment of textile materials, in particular the laundry machine according to the present invention, is of the electronically controlled type and comprises a central controller 17 capable of controlling the appliance by adjusting and controlling the various phases of the treatment of laundry for washing based on the instructions received by the user and the data detected by the sensor means, among which are the data provided by the electronic detection module 6.

As mentioned earlier, the appliance comprises a structure and an oscillating assembly. The oscillating assembly is connected to the structure by a suspension system, which comprises a pair of elements telescopically coupled to each other by two corresponding ends, a first of said two ends comprising a ferromagnetic material and a second of said two ends comprising a coil 9 .

According to the present invention, the appliance comprises an electronic detection module 6 capable of detecting a relative displacement S, of said two ends. Said electronic detection module 6 comprises an oscillator circuit 12 having an oscillation frequency f that depends on the impedance L of the coil 9, and processing means, functionally connected to said oscillator 12 and capable of detecting said oscillation frequency f and to determine, as a function of said oscillation frequency f, at least a part of the information that can be associated with the relative displacement S. Such fragment of information can also be associated, in particular in static conditions, in which it is not produced relative displacement S between the cylinder 3 and the piston 4, to the absolute position of the oscillating assembly with respect to the structure, which can be deduced from the absolute value of the axial penetration x of the end of the piston 4, made from ferromagnetic material, in the internal volume of the coil 9.

According to the embodiment of Figure 1, the coil 9 is located in the cylinder 3 of the shock absorber, while the piston 4 comprises at least a part of ferromagnetic material that travels with the cylinder 3, thereby changing the inductance of the coil 9.

Said embodiment can be modified, without departing from the scope of the present invention, according to an alternative configuration of a totally equivalent technical point of view, associating the coil 9 with the piston 4 and making the cylinder 3 from ferromagnetic material, such as It is represented in figure 4.

Figure 4 uses the same numerical references of Figure 1 to indicate the means that are identical or equivalent to those already represented in Figure 1.

According to this embodiment, the piston 4 has an end 41 telescopically coupled to one end of the cylinder 3. The end 41 is hollow and is wound with a coil 9 connected to the electronic detection module 6 by means of a wiring 8.

In turn, the cylinder 3 has an end 31 made at least partially of ferromagnetic material, which is telescoped into the cavity of the end 41 of the piston 4.

The relative displacement of the end 31 with respect to the end 41 causes a variation in the inductance of the coil 9. Said variation, as described above, determines a variation in the oscillation frequency f of an oscillator 12 comprised in the module of electronic detection 6.

Said electronic detection module 6 comprises a microcontroller 16 which, when equipped with a suitable CNT counter, determines the oscillation frequency f of the oscillator circuit 12 and determines the relative displacement between the cylinder 3 and the piston 4. The CNT counter is connected functionally to the oscillator circuit 12 and is capable of counting the phase transitions of the output signal generated by the oscillator circuit 12. According to the present invention, the microcontroller 16 is capable of transmitting to the central controller 17, via a digital communication line, a piece of information that can be associated with the relative displacement S of the oscillating set with respect to the structure.

The digital communication line between the microcontroller 16 and the central controller 17 comprises the appropriate transmission means, usually of an electrical type, and the transmission of suitable digital signals is managed by appropriate communication protocols.

Based on said fragment of information that can be associated with the relative displacement S, the central controller 17 can therefore exercise at least one control action on the appliance.

In particular, said information may be a determination of the mass or weight of the content of the oscillating assembly or of a portion of the content of the oscillating assembly.

More precisely, said piece of information is the value of the mass or weight of the textile materials loaded in the oscillating assembly before a washing treatment is initiated: the central controller 17 can use this measure of mass or weight of the textile materials loaded in the oscillating assembly to calculate at least one parameter related to a subsequent washing treatment, said parameter being preferably the appropriate amount of water or the appropriate amount of washing agents. Alternatively, said piece of information that can be associated with the relative displacement S of the oscillating assembly with respect to the structure may be the measurement of the mass or weight of the water or detergent in the oscillating assembly during operation of the appliance.

According to a preferred embodiment, the microcontroller 16 is an auxiliary unit of the central controller 17, to which it is connected by wiring 14, and the microcontroller 16 can receive instructions from the central controller

17.

It is clear that the microcontroller 16 can be arranged interchangeably in the same housing of the oscillator circuit PCB or at a certain distance from said circuit.

In the preferred embodiment, the entire electronic module 6 is arranged in the vicinity of the coil 9 in order to minimize the length of the connections between the microcontroller 16, the oscillator circuit 12 and the coil 9, thereby guaranteeing the maximum immunity to electromagnetic noise.

Advantageously, a calibration step can be performed, for example, during the final test of the appliance, so that the microcontroller 16 can associate any possible reading of the frequency f of the square wave signal generated by the oscillator 12 to a digital signal that it is interpreted by the central controller 17 as representative of a particular value of the relative displacement of the oscillating assembly with respect to the structure and / or of a particular value of one or more physical quantities related to said relative displacement (such as mass or weight of the textile materials found in the drum).

The microcontroller 16 transmits a digital signal to the central controller 17 via the communication line comprising the wiring 14.

It should be noted that the digital transmission from the microcontroller 16 to the central controller 17 is much stronger than a simple analog connection between the analog module AM (shown in Figure 2a) and the central controller 17, since it is substantially immune to noise and does not require no special protection for the wiring 14 that connects the electronic module 6 to the central controller 17. This guarantees high reliability and forecast of the measurements made using the frequency value f of the square wave signal generated by the oscillator 12, which corresponds to the measurement of the relative displacement of the oscillating set with respect to the structure and the measurements of the mass or the weight of the content of the oscillating set.

The microcontroller 16, which is adapted to generate, by measuring the frequency f of the alternating voltage signal generated by the oscillator circuit 12, a digital signal representative of the relative displacement S of the oscillating assembly with respect to the structure and / or of any other physical quantity related to said relative displacement S (among them, for example, the mass or weight of the textile materials found in the drum), is also suitable for processing the measured value of the frequency f of the signal of the square wave voltage generated by oscillator circuit 12 to compensate for errors caused by external interference. For example, the microcontroller 16 submits the measured value of the frequency fa to a digital processing stage in order to compensate for any error due to external environmental factors (e.g. temperature) or wear of the mechanical elements of the appliance's suspension system. .

Said compensation will be made based on the signals sent by the sensor means suitable for detecting parameters of the operation of the appliance (for example, according to the output signal of a thermal sensor 18 disposed in the head 13 to detect the temperature in the vicinity of the damper 1 , said head being conveniently fixed thereto), or based on algorithms that consider the variation with time of elasticity and / or the damping characteristics of the appliance's suspension system. More accurately, said algorithms comprise parts of software code created based on the experimentally obtained data and are capable of counteracting the loss of precision and reliability over time both of the measurement of the relative displacement of the oscillating set with respect to the structure of the appliance as of the measurement of any other physical quantity that can be obtained from said relative displacement.

According to a particularly advantageous embodiment of the present invention, the laundry machine comprises sensor means functionally connected to the microcontroller 16 and capable of detecting the operating parameters of the appliance, at least one of said sensor means being able to be incorporated into the module electronic 6. The electronic module 6 shown in FIG. 3 also comprises a thermal sensor 18, which is preferably an NTC type sensor, used to determine the temperature value in the head area 13. The thermal sensor 18 can be interconnected conveniently with an analog channel of the microcontroller 16 or incorporated into the microcontroller 16 (since low-cost microcontrollers having a built-in thermal sensor are currently available in the market). During operation of the home appliance, said area is in fact subjected to the action of the nearby brake element 5, which dissipates a part of the kinetic energy of the oscillating assembly in the form of heat: in particular, said action of the brake element 5 of the damper 1 is captured as a temperature value higher than the ambient temperature, which can cause deviations that alter the measurement of the relative displacement of the oscillating assembly with respect to the structure of the appliance.

In addition, such temperature variation can affect the friction of the shock absorber, thereby changing the laws that regulate the relationship between displacement and other associated quantities, such as the weight of textile materials loaded in a washing machine.

The thermal sensor 18 generates an auxiliary electrical signal that is representative of the temperature in the area of the head 13 and then sends it to the microcontroller 16. The microcontroller 16 takes into account the auxiliary electrical signal received from the thermal sensor 18 to generate the information to be sent to central controller 17 via a digital communication line.

The microcontroller 16 compensates the measurement value of the relative displacement of the oscillating assembly with respect to the structure of the appliance (or any other physical quantity related to said displacement) based on the value of the temperature detected by the thermal sensor 18, taking into account how the electrical characteristics of the coil 9 and the oscillator circuit 12 change depending on the temperature.

In the example of Figure 3, the thermal sensor 18 is incorporated into the architecture of the electronic module 6.

Advantageously, different sensor means can be conveniently associated with the electronic module 6 in order to detect different physical quantities: for example, a humidity sensor (relative or absolute) capable of detecting the humidity of the air surrounding the electronic module 6 and preventing said electronic module 6 suffers damage due to excessive humidity, or a microphone capable of detecting the noise produced by the laundry machine in order to provide a warning in case there is a risk of imminent failure of the damper 1 or any Other elements of the laundry machine according to the present invention. Preferably, the microcontroller 16 may also be able to counteract the effects caused by the wear of the appliance, which result in variations in the elasticity time and the damping characteristics of the hanger system of the laundry machine and, therefore, in the frequency of the signal generated by oscillator 12.

Said variations in elasticity and / or damping characteristics are detected as the number of operating cycles of the appliance increases and due to wear and tear that occurs over time. For example, if the electronic module 6 according to the present invention is to be used to detect the mass or weight of the content of the oscillating assembly of the laundry machine, it should be taken into account that, as time passes, it is produced a relative displacement other than the oscillating set, the mass or weight of the content of the oscillating set being equal.

In this case, it is possible that the microcontroller 16 can compensate for the effect exerted by the variations in the elasticity time and / or the damping characteristics of the suspension system of the laundry machine in the detection of the mass or of the weight of the oscillating set content. For this purpose, the microcontroller 16, by way of non-limiting example, can counteract the number of operating cycles performed by the machine and then, based on that number, associate the value of the frequency f of the signal generated by the oscillator 12 to one of the various experimentally obtained correction factors, stored in the internal memory of the microcontroller 16. In this way, the microcontroller 16 performs a compensation action that allows a sufficiently accurate and reliable measurement of the mass or weight to be obtained. of the content of the oscillating set in time.

More preferably, the information referring to the treatment cycles performed by the appliance, as well as any other information related to the wear suffered by the appliance, can be transmitted to the microcontroller 16 via the central controller 17.

In comparison with the measuring system according to the prior art, the present invention has the additional advantage of significantly reducing the workload of the electronic control system of the appliance, in particular of the central controller 17.

In fact, the information sent by the microcontroller 16 of the electronic module 6 can be used directly by the central controller 17, without the need for any additional processing, since said processing has already been carried out in a position before the central controller 17. The latter only You have to decode the digital signal sent by the microcontroller 16 to have the information included in it to control the appliance.

The transmission of the above information from the microcontroller 16 to the central controller 17 can be provided using well-known communication techniques.

The communication between the microcontroller 16 and the central controller 17 via the wiring 14 can be a unidirectional communication (for example, according to the PWM technique, in which the information is coded by acting on the duty cycle of the digital signal, which comprises, therefore, a series of pulses having a constant amplitude and frequency and a variable amplitude) or, preferably, a two-way communication (by way of non-limiting example, a two-way asynchronous series UART communication can be used).

On the transmission lines T, the microcontroller 16 transmits to the central controller 17, in the form of a digital signal, a fragment of information that can be associated with the relative displacement of the oscillating assembly with respect to the structure of the apparatus (i.e. reading of the relative displacement or of any other physical quantity related to said relative displacement) and that is conveniently compensated for the temperature and wear of the mechanical elements of the appliance.

On the receiving line R, the microcontroller 16 receives from the central controller 17 useful data for the microcontroller 16. For example, the central controller 17 can transmit to the microcontroller 16 the value of the rotational speed of the laundry machine drum , so that the microcontroller 16 can take into account the same when assessing the variation in the elasticity time and / or the damping characteristics of the suspension system. Or, still by way of example, the central controller 17 can send information about the dynamic state of the system to the microcontroller 16, so that the microcontroller 16 can more easily discern if the current measurement is a static measurement (such as a determination of the mass or weight of the laundry found in the drum before starting the washing treatment) or a dynamic measurement (such as a measure of load imbalance during operation of the appliance).

The information indicating the value of the mass or weight of the laundry for washing can be used by the machine for the treatment of textile materials in order to provide useful information for the user through its own interface device (for example, the laundry machine can warn the user when the maximum load of laundry that the appliance can treat has been reached, depending on the type of fabric, or it can indicate the appropriate amount of washing agents to be used for a certain amount of laundry clothes loaded on the drum, or can advise on the most appropriate washing program) how to automatically adapt the characteristic parameters of the treatment, in particular, the washing treatment, to the amount of laundry clothes loaded on the drum by the user, so that the consumption of the appliance is optimized (if the laundry machine is equipped with a dispensing device dor of a large capacity washing agent, if the value of the mass or weight of the laundry to be loaded on the drum is known, an optimum dosage of the washing agents may be carried out).

In order to allow the electronic detection of the module 6 according to the present invention to make accurate and reliable measurements of the mass or the weight of the content of the oscillating assembly or a part thereof, the central controller 17 transmits to the microcontroller 16 (assuming the existence of a two-way communication line between the two) at least one data that can be used by microcontroller 16 as a synchronization signal.

If the measurement refers to the mass or weight of the laundry to be loaded on the drum of the laundry machine, it is useful to adopt a synchronization signal indicating a vacuum condition within the oscillating assembly of the appliance, which allows that the microcontroller 16 relates the mismatch detected when the synchronism signal is received with the value of the tare.

Said synchronization signal transforms the measurements of the mass or weight of the content of the oscillating assembly of the laundry machine into differential measurements, thereby calculating the value of the mass or weight of the laundry clothes loaded on the drum. by the microcontroller 16 as a difference between the value of the mass or the weight corresponding to the value of the frequency instantly associated with the square wave signal generated by the oscillator circuit 12 and the value of the mass or weight corresponding to the value of the frequency associated with the square wave signal generated when the synchronism signal is sent.

In the most advantageous embodiment of the present invention, in which the communication between the central controller 17 and the microcontroller 16 is bidirectional, the synchronization signal can be provided by the signal indicating that the door of the machine for washing the clothing has been opened, which is sent to the microcontroller 16 via the central controller 17 after receiving it from the door locking device.

Alternatively, a dedicated calibration button arranged inside the interface device can be arranged, that is, a button available to the user intended to notify the central controller 17 of the vacuum condition within the oscillating assembly: in this case, the Synchronization signal can be supplied by a signal indicating that said button has been pressed.

By operating differential measurements, the electronic detection module 6 according to the present invention can also function as a sensor for the amount of water or detergent. In fact, using the start-up signal of the laundry machine as a synchronization signal once the laundry has been loaded into the drum, it is possible to measure the mass or weight of the water or detergent inside the assembly oscillating In fact, the mass and weight of the water or detergent can be calculated by the microcontroller 16 as a difference between the value of the mass or the weight obtained instantaneously during the operation of the laundry machine and the value of the mass or of the weight obtained when the synchronism signal is sent, that is, when the laundry machine has been put into operation.

When working as a sensor of the amount of water or detergent, the electronic detection module 6 allows the central controller 17 to control the means of entry and / or drainage of the water from the laundry machine (determining the opening times and closing it) only based on the information related to the mass or weight of the water or detergent present inside the oscillating assembly.

If the appliance according to the present invention is a washer / dryer machine, the electronic detection module 6 can also be used to control the drying treatment.

During the drying treatment, the microcontroller 16 can transmit to the central controller 17, at all times, the information related to the mass or weight of the oscillating assembly, and the central controller 17 can use said information to control the drying treatment. Similarly, the microcontroller 16 can determine the amount of water progressively removed from the laundry by calculation based on the reduction of the mass or the weight of the content of the oscillating assembly, and the central controller 17 can stop the drying treatment when the Amount of water removed from clothing reaches a predetermined percentage of the amount of water that is inside the oscillating assembly at the end of the wash treatment.

From the present description, it is evident that the appliance according to the present invention, in addition to overcoming the drawbacks inherent in the prior art mentioned above, also provides the additional advantage of allowing the use of the electronic module 6 to control many phases of the operation of the appliance without increasing the workload of the central controller 17.

The present invention has been described, with particular reference to some examples of specific embodiments, but it is clear that those skilled in the art can make many changes without thereby departing from the scope defined by the appended claims.

For example, the detection of the relative displacement of the oscillating assembly with respect to the structure can be provided using a pair of telescopically coupled elements that do not necessarily comprise the piston and the cylinder of a damper. These two elements may be a pair of elements specifically designed for such detection but, nevertheless, do not play any role as a buffer.

Claims (14)

1. Appliances for the treatment of textile materials, in particular, a machine for washing clothes, comprising: An oscillating assembly elastically fixed to a structure by means of a suspension system comprising a pair of elements telescopically coupled to each other by two respective ends, in which a first of said two ends comprises ferromagnetic material and a second of said two ends. comprises a coil (9), and - an electronic detection module (6) capable of detecting a relative displacement of said two ends, characterized in that said electronic module (6) comprises an oscillator circuit (12), whose oscillation frequency depends on the impedance of said coil (9), and processing means functionally linked with said oscillator and capable of measuring said oscillation frequency and determine, depending on said oscillation frequency, at least a piece of information that may be associated with said relative displacement and because said processing means comprise a microcontroller (16) comprising counting means (CNT) suitable for counting transitions phase of an output signal by said oscillator to determine the oscillation frequency thereof, and because said microcontroller (16) is able to determine said relative displacement according to a law that depends on said frequency, and because said home appliance comprises a central controller (17) capable of controlling said home appliance and functionally connected with said microcontroller (16) to receive a piece of information associated with said displacement, said central controller (17) being able to transmit to said microcontroller (16) the control parameters that are useful for the determination of said fragment of information that may be associated with said displacement, said control parameters comprising a synchronism signal indicating a vacuum condition within the oscillating assembly.

2.

An appliance according to the preceding claim, characterized in that said oscillator circuit (12) is capable of generating a square wave signal.

3.

An appliance according to any of the preceding claims, characterized in that said oscillator is a non-stable multivibrator.

Four.

An appliance according to any one of claims 1 to 3, characterized in that it comprises sensor means functionally connected to said microcontroller (16) and capable of detecting the operating parameters of said appliance.

5.

An appliance according to claim 4, characterized in that said sensor means comprise a thermal sensor sensor (18), preferably an NTC type sensor.

6.

Appliance according to claim 1, characterized in that said control parameters comprise information regarding the wear of the appliance.

7.

Appliance according to claim 1 or 6, characterized in that said control parameters comprise information relating to the operating phases of said appliance.

8.

An appliance according to any one of claims 1 or 6 or 7, characterized in that said microcontroller

(16) is capable of transmitting said information to said central controller (17) via a digital communication line.

9.

An appliance according to any one of the preceding claims, characterized in that said electronic detection module (6) is located in one of said two elements.

10.

An appliance according to any one of claims 1 or 6 or 7 or 8 or 9, characterized in that said information is the measurement of the mass or weight of the content of said oscillating assembly or of a portion of said content of said oscillating assembly.

eleven.

An appliance according to any one of claims 1 or 6 or 7 or 8 or 9, characterized in that said information is the measurement of the mass or weight of the textile materials loaded in said oscillating assembly before subjecting said textile materials to a treatment, in particular , to a wash treatment.

12.

An appliance according to any one of claims 1 or 6 or 7 or 8 or 9, characterized in that said central controller (17) uses said information to calculate at least one parameter related to a subsequent washing treatment, said parameter being preferably the appropriate amount of water or the right amount of washing agents.

13.

Appliance according to any of the preceding claims, characterized in that it comprises an interface device through which said appliance communicates said information and / or parameter to a user.

14. An appliance according to any one of the preceding claims, characterized in that said coil (9) is located at one end of the cylinder (3) of a damper (1) and that said end comprising ferromagnetic material is an end of a piston (4) of said shock absorber (1). 15. Appliance according to any of claims 1 to 14, characterized in that the coil (9) is 10 located at one end (41) of the piston (4) of a shock absorber (1) and because said end (31) comprising ferromagnetic material is an end of a cylinder of said shock absorber (1).