Method for controlling a kneading household appliance depending on a determination regarding a work tool

Abstract

The invention relates to a method for controlling a kneading household appliance (1) depending on a determination regarding an employed work tool (2a, 2b, 2c), comprising: - a step of defining a desired work tool (2a, 2b, 2c); - a step of deducing a fundamental frequency (Ff) depending on the desired work tool (2a, 2b, 2c); - a step of attaching an employed work tool (2a, 2b, 2c); - a step of causing the kneading household appliance (1) to operate; - a step of reading a supply current (C) of a main motor; - a step of determining an amplitude (A) of a Fourier transform of the supply current (C) for the fundamental frequency (Ff); - a step of comparing the amplitude (A) with a comparison criterion; - a step of controlling the kneading household appliance (1) depending on the comparison step.

Description

Method for controlling a kneading kitchen appliance based on a determination of a working tool

[0001] The invention relates to the field of kneading household appliances and more particularly to a method for determining a working tool. Prior art

[0002] A kneading appliance consists of a bowl attached to a main body. The bowl holds the ingredients necessary to prepare a food item, hereafter referred to as a "preparation." A preparation comprises one or more ingredients and may be a mixture of dry or liquid ingredients, and may take the form of a dough, a mousse, a powder, etc.

[0003] The kneading appliance is used to work the preparation in order to modify its texture, for example by mixing, whipping or kneading it.

[0004] Mixing means combining several ingredients together to obtain a homogeneous preparation.

[0005] Whisking means the action of vigorously beating the preparation in order to incorporate air and give it a light and frothy consistency.

[0006] Finally, kneading refers to work done on the preparation to make it more elastic by developing the gluten present in said preparation.

[0007] The preparation work is done using specific interchangeable tools including: A dough hook is specially designed for kneading heavy doughs, such as those used for making bread; A mixing sheet allows mixing for lighter preparations, such as cake batters or preparations requiring a finer texture; A whisk allows whipping ingredients such as egg whites or cream, allowing the creation of airy and frothy mixtures.

[0008] Generally, the main body includes a base to ensure the stability of the stand mixer on a work surface. This base extends into a head, which is usually mobile and rotates relative to the base. The attachment is then mounted onto this head. The main body, and more specifically the head of the stand mixer, includes several drive outputs designed to power the attachment at different speeds. Typically, each attachment is designed to be easily removed and attached to a single drive output. In other words, there is a keyed connection between a drive output and a specific attachment.

[0009] However, some household appliances may offer the possibility that the same work tool can be attached to one or the other of the drive outputs depending on the use of the work tool which must be made during the preparation of a culinary product.

[0010] All the drive shafts are rotated by a main motor, located in the main body, for example in the foot. When the dough mixer is switched on, all the drive shafts rotate, whether or not a work tool is attached.

[0011] A user of a stand mixer is not a pastry expert and may make mistakes when positioning the attachment. For example, they might use the dough hook instead of the whisk to prepare whipped cream, which will not produce the desired result.

[0012] Therefore, there is a need for a kneading appliance that detects the attached working tool and determines whether it is suitable for the task to be done on the preparation.

[0013] A known solution for detecting which tool is attached to a dough mixer is to use a near-field communication (NFC) sensor. Such a sensor includes a transmitter located in the head of the main unit and a tag attached to each tool. Each tag on a tool is configured differently from a tag on a different tool, allowing the type of tool attached to the mixer to be identified.

[0014] However, this solution is not entirely satisfactory, particularly in terms of reliability and the cost associated with adding extra sensors to the dough mixer. Furthermore, if the same tool can be attached to multiple drive outputs, a near-field sensor, while able to identify that a particular type of tool is attached to the appliance, cannot reliably determine which drive output it is attached to.

[0015] Therefore, there is a need for a reliable, inexpensive, robust and fast solution that can detect the positioned work tool in order to guarantee an optimum result in the preparation.

[0016] An embodiment relates to a method of controlling a kneading household appliance as a function of a determination of a working tool used, said working tool used being fixed to a drive output among a plurality of drive outputs of a kneading household appliance (1), said working tool being uniquely matched to said drive output, said drive outputs (3) forming an assembly which is rotated by a main motor, said method being implemented by said appliance (1) and comprising at least: a definition step in which at least one desired working tool is defined; a deduction step in which at least one fundamental frequency is determined as a function of at least the desired working tool; a fixing step in which the working tool used is fixed to one of the drive outputs;a step of starting up the kneading appliance in which all the drive outputs are rotated by the main motor; a step of recording the supply current of the main motor over an operating period; a determination step in which a value of the amplitude (A) of a Fourier Transform of the supply current (C) for at least one fundamental frequency is determined; a comparison step in which a suitability parameter is determined based on a comparison of at least one amplitude value with a comparison criterion; a step of controlling the kneading appliance based on the suitability parameter.

[0017] A stand mixer consists of a bowl attached to a main body. Typically, the main body has a foot extending into a head, the head rotating relative to the foot. During use, the foot rests on a work surface. The head rotates about an axis extending horizontally from the work surface during use.

[0018] The dough mixer has multiple drive outlets; each working tool is designed to be attached to a single drive outlet, and each drive outlet can only accommodate one working tool. In other words, there is a pairing between a drive outlet and a working tool.

[0019] The drive outputs are rotated together by a main motor, located in the main body, for example, in the base. The main motor is electrically powered. A user can select different operating speeds corresponding to different rotational speeds of each drive output. In other words, each drive output rotates at a different speed for the same selected operating speed. For a given operating speed selected by a user, each workpiece will have a different rotational speed. This is because the reduction ratio between the motor and the drive output is different for each drive output, so that a selected operating speed corresponds to several rotational speeds depending on the workpiece.

[0020] The working tool could, for example, be a dough hook, a mixing sheet, or a whisk.

[0021] The method according to the invention makes it possible to determine whether the desired working tool is indeed the working tool being used. In other words, the method determines whether the user has positioned the correct working tool. To this end, the method analyzes the amplitude of the Fourier transform of the main motor's supply current at at least one fundamental frequency.

[0022] The Fourier transform is a mathematical tool used to decompose the main motor's supply current into the frequency domain. This decomposition gives the amplitude, or quantity, of each frequency in the supply current for a given time period. Thus, the decomposition allows for the analysis of the current's frequency properties, notably determining the amplitude of the supply current at the fundamental frequency. Several Fourier transforms exist, such as the Discrete Fourier Transform and the Fast Fourier Transform.

[0023] The process includes a definition step in which the desired working tool is defined. The desired working tool corresponds to the working tool that the user wants or needs to use to obtain a desired result on the preparation.

[0024] The process also includes a deduction step in which at least one fundamental frequency is determined based on the desired working tool. At the end of the deduction step, the at least one fundamental frequency is known.

[0025] The fundamental frequency is a function of the rotational speed of the working tool. Therefore, for each rotational speed, a fundamental frequency is determined, which is preferentially detected in a harmonic spectrum of the power supply current—that is, the representation of the power supply current amplitudes as a function of frequency. The harmonic spectrum is obtained by decomposing the power supply current using a Fourier transform. Since each working tool rotates at a different speed, knowing the desired working tool allows us to determine at least one fundamental frequency that must be detected in the harmonic spectrum of the power supply current if this tool is correctly attached to the kneading appliance. In case of error, at least one fundamental frequency will not be present in the harmonic spectrum.

[0026] The process then includes a fixing step in which the working tool being used is fixed to one of the drive outputs. It is during this step that the user can accidentally fix the wrong working tool and attach a different one than the intended one.

[0027] The start-up step involves energizing the main motor to rotate the drive outputs. This sets the working tool in motion to process the prepared material.

[0028] The recording step consists of recording the motor's supply current over an operating period. In other words, when the kneading appliance is in operation, the kneading appliance records the supply current value, for example, by means of a Hall effect sensor placed in series on the motor's power supply terminals.

[0029] The process then includes a determination step in which a value for the amplitude of the Fourier Transform of the supply current is determined for at least one fundamental frequency. During the determination step, the kneading appliance calculates the Fourier Transform of the supply current and deduces the amplitude value at at least one fundamental frequency for the operating period.

[0030] Thus, after the determination step, the amplitude for at least one fundamental frequency is known for the operating period.

[0031] Next, the process includes a comparison step in which a goodness-of-fit parameter is determined based on a comparison of at least one amplitude value with a comparison criterion.

[0032] The suitability parameter can be, for example, a boolean suitability parameter "work tool used identical to the desired work tool" / "work tool used different from the desired work tool".

[0033] The comparison criterion can be a function of the fundamental frequency and / or the desired working tool. The comparison criterion can be a threshold, for example. The comparison step then includes a phase of reading the comparison criterion from memory.

[0034] For example, the amplitude at the fundamental frequency validates the comparison criterion, the working tool used is identical to the desired working tool.

[0035] At the beginning of the mixing process, the amplitude of the fundamental frequency at which the working tool rotates is high because this value is characteristic of the rotational speed of the working tool.

[0036] Analyzing the amplitude of at least one fundamental frequency therefore allows us to determine which working tool is actually fixed on the training output, and to deduce the suitability with the desired working tool.

[0037] Finally, the process includes a control step in which the kneading appliance is controlled according to the suitability parameter.

[0038] The method according to the invention has the advantage of assisting the user during preparation to ensure that the fixed working tool corresponds to the desired working tool in order to obtain an optimum result.

[0039] The subject of this presentation may also exhibit one or more of the following characteristics, taken alone or in combination.

[0040] In some embodiments, during the definition step, a selected operating speed is defined, and during the deduction step, at least one fundamental frequency is also deduced as a function of the selected operating speed.

[0041] Thus, the selected operating speed is known by the kneading appliance and is used to determine at least one fundamental frequency.

[0042] The selected operating speed can be determined by means of a sensor present in the kneading appliance or indicated by the user.

[0043] Information about the desired working tool and the selected operating speed allows us to determine the theoretical rotational speed of the working tool being used, and therefore the value of the fundamental frequency that should be detected in the harmonic spectrum of the supply current. If this fundamental frequency is not detected, the working tool being used is different from the desired working tool.

[0044] According to one embodiment, the definition and deduction step is carried out after the commissioning step but before the survey step.

[0045] In some embodiments, during the deduction step, a plurality of fundamental frequencies are deduced according to the desired working tool, and during the determination step, the value of the amplitude of the Fourier Transform for each fundamental frequency is determined.

[0046] In this case, the kneading appliance has a plurality of predetermined operating speeds. In other words, the kneading appliance can only operate at certain speed values. Therefore, the kneading appliance has a plurality of discrete operating speeds.

[0047] According to one embodiment, the kneading appliance includes between 2 and 15 predetermined operating speeds, preferably between 5 and 10, and in particular 8.

[0048] Thus, knowing the desired working tool, it is possible to determine the tool's rotational speed for each possible operating speed and ultimately a fundamental frequency for each predetermined operating speed. A correspondence between the operating speed, the rotational speed, and the working tool can be recorded in a lookup table.

[0049] Indeed, if the desired working tool is the one actually used, one of these fundamental frequencies will be present in the harmonic spectrum of the supply current. Conversely, if the desired working tool is not the one actually used, none of these fundamental frequencies will be present in the harmonic spectrum of the supply current.

[0050] Determining the value of the amplitude of the Fourier Transform for each fundamental frequency allows us to determine if one of these fundamental frequencies is present in the harmonic spectrum of the supply current.

[0051] In some embodiments, during the definition stage, the desired working tool is defined according to a type of preparation desired or the working tool is specified by a user.

[0052] The type of preparation can be a cooking recipe, or a family of preparations such as "brioche dough", "bread dough", "whipped cream", etc.

[0053] Based on this type of preparation, it is possible to determine the work tool to be used. Alternatively, the user can directly specify the work tool they wish to use.

[0054] In some embodiments, the control step consists of stopping the rotation of the drive outputs and / or issuing an alert signal.

[0055] Depending on the suitability parameter, and more specifically if a discrepancy is detected between the desired working tool and the working tool used, the control step consists of stopping the rotation of the drive outputs and / or issuing an alert signal.

[0056] The warning signal can be audible or visual.

[0057] Stopping the rotation of the training outputs and therefore of the working tool allows the user to change the working tool before the preparation is a failure.

[0058] In some embodiments, during the determination step, the supply current is sampled according to a sampling time.

[0059] In some embodiments, the sampling time is between 0.5ms and 10ms, preferably between 1ms and 5ms, and in particular 2ms.

[0060] The sampling time allows the main motor's supply current to be accurately represented.

[0061] In some embodiments, the operating period is between 10s and 100s, preferably between 15s and 40s, and in particular 20s.

[0062] The chosen operating period allows for the correct representation of the fundamental frequencies of the preparation.

[0063] In some embodiments, the comparison step includes a phase of reading the comparison criterion from a memory.

[0064] The comparison criterion is then defined, for example, by an experiment and recorded in a table as a function of the fundamental frequency.

[0065] One embodiment relates to a kneading appliance comprising at least one preparation working tool which is fixed to a drive output, said drive output being rotated by a main motor, the kneading appliance implementing the process according to the invention.

[0066] The invention will be better understood from the following description, which relates to one or more embodiments of the present invention, given by way of non-limiting examples and explained with reference to the accompanying schematic drawings, in which:

[0067] is a schematic representation of a kneading household appliance according to the invention and two working tools;

[0068] is a curve illustrating a main motor supply current as a function of time during the preparation of brioche dough with a dough hook and a selected operating speed of 4;

[0069] is a harmonic spectrum of the supply current representing a signal amplitude as a function of a frequency for an operating period between 400s and 500s of the curve of the;

[0070] is a harmonic spectrum for an operating period of between 20s and 40s of a supply current recorded during the preparation of whipped cream with a whisk and a selected operating speed of 5.

[0071] Only the elements necessary for understanding the invention have been shown. To facilitate reading the drawings, the same elements bear the same reference numbers from one figure to another.

[0072] An embodiment relates to a method of controlling a kneading appliance 1 during the preparation of a mixture M. The mixture M comprises one or a plurality of ingredients, and may be a mixture of dry or liquid ingredients, and may be in the form of a paste, a foam, a powder, etc.

[0073] The kneading appliance 1, as shown in the figure, comprises a bowl 4 which is attached to a main body 5. The main body 5 is equipped with a foot 5a extending into a head 5b, the head 5b being rotatable relative to the foot 5a. The foot 5a of the kneading appliance 1 rests, in use, on a work surface. The head 5b is rotatable relative to an axis extending horizontally from said work surface, in use.

[0074] A working tool 2a, 2b, 2c is a tool designed to be attached to a drive output 3 of the main body 5, and more specifically to one of the drive outputs 3 of the head 5b of the main body 5.

[0075] The kneading appliance 1 comprises a plurality of drive outputs 3; each working tool 2a, 2b, 2c is designed to be detachably attached to a single drive output 3, and each drive output 3 can only receive one working tool 2a. In other words, there is a pairing between a drive output 3 and a working tool 2a.

[0076] The drive outputs 3 are rotated together by means of a main motor, located in the main body 5, for example in the foot 5a. The main motor is electrically powered by a mains supply. A user can select different operating speeds using a control device 6. Each selected operating speed corresponds to a different rotational speed of the drive output 3. In other words, each drive output 3 of the plurality of drive outputs rotates at a different speed for the same selected operating speed. For a given operating speed selected by a user, each working tool 2a, 2b, 2c will have a different rotational speed.Indeed, a reduction ratio between the motor and the drive output 3 is different for each of the drive outputs so that a selected operating speed corresponds to several rotation speeds depending on the working tool 2a, 2b, 2c.

[0077] The working tool 2a, 2b, 2c can for example be a dough hook 2a, a mixing sheet 2b, or a whisk 2c.

[0078] The table below indicates the rotational speed of the working tool 2a, 2b, 2c in the case of a plurality of drive outputs 3 rotating at different speeds thanks to different reduction ratios:

[0079] [Table 1] Selected operating speed Hook 2a rotation speed (rpm) Whisk 2b rotation speed (rpm) 11 20 19 82 15 72 59 31 90 31 44 22 33 69 52 90 47 96 35 05 78 73 96 65 58 44 07 26

[0080] The method according to the invention makes it possible to determine whether the desired working tool 2a, 2b, 2c is indeed the working tool 2a, 2b, 2c in use. In other words, the method determines whether the user has positioned the correct working tool 2a, 2b, 2c. To do this, the method analyzes the amplitude of a Fourier transform of a supply current C from the main motor at at least one fundamental frequency Ff.

[0081] The process includes a definition step in which the desired working tool 2a, 2b, 2c is defined. The desired working tool 2a, 2b, 2c corresponds to the working tool 2a, 2b, 2c that the user wants or needs to use to obtain a desired result on preparation M.

[0082] In some embodiments, during the definition step, a selected operating speed is defined, and during the deduction step, at least one fundamental frequency Ff is also deduced as a function of the selected operating speed.

[0083] Thus, the selected operating speed is known by the kneading appliance 1 and is used to determine at least one fundamental frequency Ff.

[0084] The selected operating speed can be determined by means of a sensor present in the kneading appliance 1 or indicated by the user.

[0085] Information regarding the desired working tool 2a, 2b, 2c and the selected operating speed allows us to know the theoretical rotational speed of the working tool 2a, 2b, 2c used and therefore the value of the fundamental frequency Ff to be detected in a harmonic spectrum of the supply current C. If this fundamental frequency Ff is not detected, the working tool 2a, 2b, 2c used is different from the desired working tool 2a, 2b, 2c.

[0086] According to one embodiment, the definition step and a deduction step are carried out after an operational step but before a survey step.

[0087] In some embodiments, during the definition step, the desired working tool 2a, 2b, 2c is defined according to a desired preparation type M.

[0088] The preparation type M can be a cooking recipe, or a family of preparations such as "brioche dough", "bread dough", "whipped cream", etc.

[0089] Based on this type of preparation M, it is possible to determine which working tool 2a, 2b, or 2c should be used. Alternatively, the user can directly specify the working tool they wish to use.

[0090] The process also includes a deduction step in which at least one fundamental frequency Ff is determined based on the desired working tool 2a, 2b, 2c. At the end of the deduction step, the at least fundamental frequency Ff is known.

[0091] The fundamental frequency Ff is a function of the rotational speed of the working tool 2a, 2b, 2c. Therefore, for each rotational speed, a fundamental frequency Ff is determined, which is preferentially detected in the harmonic spectrum of the supply current C. This spectrum represents the amplitudes A of the supply current C as a function of frequency, as illustrated in Figures 3 and 4. The harmonic spectrum is obtained by decomposing the supply current C using a Fourier transform. Since each working tool 2a, 2b, 2c rotates at a different speed, knowing the desired working tool 2a, 2b, 2c allows us to determine at least one fundamental frequency Ff that must be detected in the harmonic spectrum of the supply current C if this tool is correctly attached to the kneading appliance 1. In case of error, at least one fundamental frequency Ff will not be present in the harmonic spectrum.

[0092] In some embodiments, during the deduction step, a plurality of fundamental frequencies Ff are deduced as a function of the desired working tool 2a, 2b, 2c. In this case, the kneading appliance 1 comprises a plurality of predetermined operating speeds. In other words, the kneading appliance 1 can only operate at certain speed values. The kneading appliance 1 therefore comprises a plurality of discrete operating speeds.

[0093] According to one embodiment, the kneading appliance 1 comprises between 2 and 15 predetermined operating speeds, preferably between 5 and 10, and in particular 8.

[0094] Thus, knowing the desired working tool 2a, 2b, 2c, it is possible to determine the rotational speed of the working tool 2a, 2b, 2c for each possible operating speed and finally a fundamental frequency Ff for each predetermined operating speed. A correspondence between the operating speed, the rotational speed, and the working tool 2a, 2b, 2c can be recorded in a lookup table, as illustrated in Table 1.

[0095] Indeed, if the desired working tool 2a, 2b, 2c is the one actually used, one of these fundamental frequencies Ff will be present in the harmonic spectrum of the supply current C. Conversely, if the desired working tool 2a, 2b, 2c is not the one actually used, none of these fundamental frequencies Ff will be present in the harmonic spectrum of the supply current C.

[0096] The process then includes a fixing step in which the working tool 2a, 2b, 2c used is fixed to one of the drive outputs 3. It is during this step that the user can make a mistake with the working tool 2a, 2b, 2c and fix a working tool 2a, 2b, 2c different from the desired working tool 2a, 2b, 2c.

[0097] The start-up step consists of switching on the main motor so as to rotate the drive outputs 3. Thus, the working tool 2a, 2b, 2c is set in rotation so as to work the preparation M.

[0098] The recording step consists of recording the motor's supply current C over an operating period as illustrated in. In other words, when the kneading appliance 1 is in operation, the kneading appliance 1 records the value of the supply current C, for example by means of a Hall effect sensor placed in series on the motor's supply terminals.

[0099] In some embodiments, the operating period is between 10s and 100s, preferably between 15s and 40s, and in particular 20s. The chosen operating period allows for the correct representation of the fundamental frequencies of preparation M.

[0100] The process then includes a determination step in which a value of the amplitude A of the Fourier Transform of the supply current C for at least one fundamental frequency Ff is determined. During the determination step, the kneading appliance 1 calculates the Fourier Transform of the supply current C and deduces the value of the amplitude A at at least one fundamental frequency Ff for the operating period. The Fourier Transform is a mathematical tool that allows the supply current C of the main motor to be decomposed in the frequency domain. This decomposition gives the amplitude A, or the quantity, of each frequency F in the supply current C for the considered time period, as illustrated in Figures 3 and 4. Thus, the decomposition makes it possible to analyze the frequency properties of the current, in particular to determine the value of the amplitude A of the supply current C at the fundamental frequency Ff.There are several Fourier transforms such as the Discrete Fourier Transform and the Fast Fourier Transform.

[0101] During the determination step, the value of the amplitude A of the Fourier Transform for each fundamental frequency Ff is determined, once several fundamental frequencies Ff have been deduced. Determining the value of the amplitude A of the Fourier Transform for each fundamental frequency Ff allows us to determine if any of these fundamental frequencies Ff are present in the harmonic spectrum of the supply current C.

[0102] In some embodiments, during the determination step, the supply current is sampled at a sampling time. In some embodiments, the sampling time is between 0.5 ms and 10 ms, preferably between 1 ms and 5 ms, and in particular 2 ms. The sampling time allows for the accurate representation of the supply current C of the main motor.

[0103] For example, Figure 1 illustrates the harmonic spectrum of the supply current C during the preparation of brioche dough with a dough hook and a selected operating speed of 4. The dough hook has a rotational speed, according to Table 1, of 223 rpm when the selected operating speed is four. For this rotational speed, experience indicates that the fundamental frequency Ff found in the harmonic spectrum of the supply current C is 3.95 Hz, as illustrated in Figure 1.

[0104] Furthermore, Figure 1 illustrates the harmonic spectrum of the supply current C during the preparation of whipped cream with a whisk and a selected operating speed of five. The whisk has a rotation speed, according to Table 1, of 479 rpm when the selected operating speed is five. For this rotation speed, experience indicates that the fundamental frequency Ff found in the harmonic spectrum of the supply current C is 8 Hz, as illustrated in Figure 1.

[0105] We also know that when the selected operating speed is five, the rotation speed of the kneading hook is 290rpm, which corresponds to a fundamental frequency of 4.83Hz.

[0106] Thus, if the dough hook had been attached in place of the whisk, with the selected operating speed of five, the harmonic spectrum of the supply current C would not show a line at the frequency 8Hz as illustrated in, but a line at the frequency 4.83Hz.

[0107] Thus, after the determination step, the amplitude A for at least one fundamental frequency Ff is known for the operating period.

[0108] Next, the process includes a comparison step in which a goodness-of-fit parameter is determined based on a comparison of at least one amplitude value A with a comparison criterion.

[0109] The suitability parameter can be, for example, a boolean suitability parameter "work tool used identical to the desired work tool" / "work tool used different from the desired work tool".

[0110] The comparison criterion can be a function of the fundamental frequency and / or the desired working tool 2a, 2b, 2c. The comparison criterion can be a threshold, for example. The comparison step then includes a phase of retrieving the comparison criterion from memory. The comparison criterion is then defined, for example, through experimentation and recorded in a table as a function of the fundamental frequency.

[0111] For example, when the amplitude A at the fundamental frequency Ff validates the comparison criterion, the working tool 2a, 2b, 2c used is identical to the desired working tool 2a, 2b, 2c, as is the case on the.

[0112] At the beginning of the mixing, the amplitude A of the fundamental frequency Ff at which the working tool 2a, 2b, 2c rotates is high because this value is characteristic of the rotation speed of the working tool 2a, 2b, 2c.

[0113] The analysis of the amplitude A of at least one fundamental frequency Ff therefore makes it possible to determine which working tool 2a, 2b, 2c is actually fixed on the drive output 3, and to deduce the suitability with the desired working tool 2a, 2b, 2c.

[0114] Finally, the process includes a control step in which the kneading appliance 1 is controlled according to the suitability parameter. In some embodiments, the control step consists of stopping the rotation of the drive outputs and / or emitting a warning signal. The warning signal may be audible or visual. Stopping the rotation of the drive outputs, and therefore of the working tool 2a, 2b, 2c in use, allows the user to change the working tool 2a, 2b, 2c before the preparation fails.

[0115] The method according to the invention has the advantage of assisting the user during preparation to ensure that the fixed working tool 2a, 2b, 2c corresponds to the desired working tool 2a, 2b, 2c in order to obtain an optimum result.

[0116] Although the present invention has been described with reference to specific embodiments, it is evident that modifications and changes can be made to these examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the various embodiments illustrated / mentioned can be combined in additional embodiments. Therefore, the description and drawings should be considered in an illustrative rather than restrictive sense.

[0117] It is also evident that all the characteristics described with reference to a process are transposable, alone or in combination, to a device, and conversely, all the characteristics described with reference to a device are transposable, alone or in combination, to a process.

Claims

A method for controlling a kneading appliance (1) based on a determination of a working tool (2a, 2b, 2c) used, said working tool (2a, 2b, 2c) being fixed to a drive output (3) from among a plurality of drive outputs of a kneading appliance (1), said working tool being uniquely matched to said drive output, said drive outputs (3) forming an assembly which is rotated by a main motor, said method being implemented by said appliance (1) and comprising at least: a definition step in which at least one desired working tool (2a, 2b, 2c) is defined; a deduction step in which at least one fundamental frequency (Ff) is determined based on at least the desired working tool (2a, 2b, 2c); a fixing step in which the working tool (2a, 2b, 2c) used is fixed on one of the training outputs (3);a step of starting up the kneading appliance (1) in which all the drive outputs (3) are rotated by the main motor; a step of recording the supply current (C) of the main motor over one operating period; a determination step in which a value of the amplitude (A) of a Fourier Transform of the supply current (C) for at least one fundamental frequency (Ff) is determined; a comparison step in which a suitability parameter is determined as a function of a comparison of at least one value of the amplitude (A) with a comparison criterion; a control step of the kneading appliance (1) as a function of the suitability parameter. A method according to claim 1, wherein in the definition step, a selected operating speed is defined, and in the deduction step, at least one fundamental frequency (Ff) is also deduced as a function of the selected operating speed. A method according to claim 1, wherein in the deduction step, a plurality of fundamental frequencies (Ff) are deduced as a function of the desired working tool (2a, 2b, 2c), and in the determination step, the value of the amplitude (A) of the Fourier Transform for each fundamental frequency (Ff) is determined. A method according to any one of the preceding claims, wherein during the definition step, the desired working tool (2a, 2b, 2c) is defined according to a desired preparation type (M) or the working tool (2a, 2b, 2c) is specified by a user. A method according to any one of the preceding claims, wherein the control step consists of stopping the rotation of the drive outputs (3) and / or emitting an alert signal. A method according to any one of the preceding claims, wherein during the determination step, the supply current (C) is sampled according to a sampling time. A method according to any one of the preceding claims, wherein the operating period is between 10s and 100s, preferably between 15s and 40s, and in particular 20s. A method according to any one of the preceding claims, wherein the comparison step includes a phase of reading the comparison criterion from a memory. kneading household appliance (1) comprising at least one working tool (2a, 2b, 2c) for a preparation (M) which is fixed to a drive output (3), said drive output (3) being rotated by a main motor, the kneading household appliance (1) implementing the process according to any one of the preceding claims.

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