Food processing device

Abstract

A food processing apparatus is disclosed which comprises a drive assembly comprising a motor and a drive shaft connected to the motor, and comprising a food processing tool attached to the drive shaft so as to extend into a food processing bowl in use for processing food ingredients. A sensor is provided in the apparatus, the sensor being configured to measure a characteristic of the drive assembly and to generate a signal indicative of the characteristic. A processor is also provided in the apparatus, the processor being configured to identify a repeated variation of the characteristic relative to a moving average of the characteristic based on the signal received from the sensor, and to control the food processing apparatus based on the identification.

Description

Technical Field

[0001] This invention relates to a food processing apparatus and its control method. Background Technology

[0002] Food processing devices, such as stand mixers (also known as kitchen machines), can be required to apply relatively large forces for extended periods, especially when processing dough for making bread, pizza, cakes, or similar ingredients. This processing is typically performed using removably attached food processing tools such as dough hooks, paddles, blades, augers, or similar rotary motor-driven tools. This can be driven from below (as in a mixer) or from above (as in a hand mixer or stand mixer).

[0003] However, some elements of manual processing can be difficult to replicate using motor-driven appliances. This includes determining how food processing should change over time, when it should be performed to avoid over- or under-processing, and how and when to communicate the food's condition to the user. Therefore, there is a need to find a solution for more efficient and effective use of motor power to provide users with convenient and efficient food processing.

[0004] One known method of controlling food processing equipment is to use a proportional-integral-derivative (PID) controller or a similar controller using a closed-loop motor control algorithm to control the food processing equipment motor to operate at a continuous speed selected by the user by automatically changing the voltage / current applied to the motor, regardless of changes in the motor load. However, these cannot be used to predict changes in the motor load or even before they occur, or to compensate well for periodic changes in the motor load.

[0005] The existing solution proposes using the derivative of the moving average of the current drawn by the motor to determine the state of the food being processed. However, this is affected by the following drawback: the moving average smooths out and suppresses periodic changes during processing, meaning the system cannot make adaptive adjustments to it.

[0006] Periodic variations in the motor load in food processing equipment can cause positively reinforced wobbling of the machine relative to the surface it sits on or of machine components relative to the machine's base. For example, in a stand mixer acting on a heavy load of dough, a side-to-side bending of the mixer head relative to the support and / or base can be observed. This is unsightly, noisy, and can lead to fatigue (e.g., metal fatigue) of the repeatedly bending components. Adding metal reinforcing elements (e.g., dampers) to the structure of the device can suppress this bending, but this results in greater weight and cost and is relatively ineffective for vibrations transmitted through them.

[0007] The present invention aims to at least partially improve the aforementioned problems of the prior art. Summary of the Invention

[0008] In one aspect of the invention, a food processing apparatus is disclosed, comprising a drive assembly including a motor and a drive shaft connected to the motor; and a food processing tool attached to the drive shaft for extending into a food processing container in use for processing food ingredients therein. A sensor is provided, configured to measure a characteristic of the drive assembly, and the sensor generates a signal indicative of the characteristic. A processor is provided, configured to identify repetitive variations in the characteristic relative to a moving average value based on the signal received from the sensor, and to control the food processing apparatus based on the identification.

[0009] In this way, food processing equipment can detect and account for periodic changes relative to the rolling average.

[0010] Preferably, the characteristic is at least one of the following: - The torque acting on the drive assembly - The speed of the driving components.

[0011] Any one of these can be a useful measure for assessing the state of the driving component.

[0012] Optionally, the processor is configured to control the food processing apparatus to perform at least one of the following: a) The control user interface sends device status indications to the user. b) Control the user interface to display ingredient type indications to the user. c) Control the user interface to display an indication of the type of food processing tool to the user. d) The wireless communication module of the food processing apparatus controls the transmission of wireless signals indicating the apparatus status to external electronic devices. e) Control the motor to stop. f) Control the motor to change its speed. g) Control the motor to continue running until the repetitive changes stop. h) Control the heating or cooling elements of the food processing apparatus to change the temperature of the container.

[0013] These can all provide users with convenient and enhanced functionality.

[0014] Alternatively, the frequency of the repetition of periodic changes is determined by the rotation cycle of the food processing tool within the food processing container. This can have the advantage of allowing the identification of repetitive interactions between the food processing tool and the food.

[0015] Preferably, the frequency of the periodic variation is at least 1 Hz, and more preferably between 1 Hz and 50 Hz. These correspond to the normal operating frequency of the rotation of the drive components and allow for the identification of repetitive impacts on the tool.

[0016] Preferably, the processor is configured to use a periodic perturbation suppression algorithm to identify recurring variations. This allows for fast and accurate identification.

[0017] Optionally, the processor includes: an averaging module configured to obtain a moving average of the characteristic; and a band-stop filter configured to generate a disturbance signal based on the difference between the moving average and the characteristic. The processor is configured to generate a control signal based on the disturbance signal for controlling the food processing apparatus. This allows for compensation of short-cycle periodic variations.

[0018] Preferably, the control signal is generated based on the derivative of the disturbance signal. This can enhance the predictive control of the food processing equipment.

[0019] Optionally, the control signal is a compensation signal, and the processor also includes a long-period variation controller configured to generate a long-period variation control signal based on the sensed long-period variation, and the processor is configured to add the compensation signal to the long-period variation control signal to obtain a true control signal for the long-period variation.

[0020] Preferably, the actual control signal is a motor control signal, and more preferably, it is the voltage applied to the motor. In this way, the motor can be controlled to at least partially suppress periodic variations.

[0021] Preferably, the motor control signal is the voltage applied to the motor, and the compensation signal is limited to no more than 5% to 50% of the maximum voltage that the processor can apply to the motor. In this way, excessive voltage can be avoided.

[0022] Optionally, the frequency of this long-period variation is less than 1 Hz.

[0023] Preferably, the band-stop filter includes a low-pass filter configured to exclude high-frequency noise, and more preferably, the low-pass filter is configured to exclude noise at a frequency that is a multiple of the expected maximum value due to the expected normal operation of the device, more preferably 10 times the expected maximum value. In this way, noise can be reduced and control enhanced.

[0024] Preferably, the averaging module includes a buffer having at least 5 slots, and more preferably between 5 and 100 slots.

[0025] In another aspect of the present invention, a method for controlling a food processing apparatus is disclosed, comprising the following steps: (i) A food processing apparatus having a drive assembly and a food processing tool, the drive assembly including a motor and a drive shaft connected to the motor, the food processing tool being attached to the drive shaft so as to extend into a food processing container in use for processing food ingredients therein. (ii) Measure the characteristics of the drive component and generate a signal based on the measured characteristics. (iii) Calculate the moving average of the stated characteristic. (iv) Identify the periodic changes of the characteristic relative to the moving average. (v) Controlling the food processing apparatus based on the identification.

[0026] Preferably, step (iv) includes applying a periodic perturbation algorithm to the measured characteristics.

[0027] In another aspect of the invention, a benchtop mixer is disclosed, comprising a head unit and a support unit hingedly attached to the head unit, and further comprising a mechanical damper positioned between the head unit and the support unit. In this way, when the head of the benchtop mixer is hinged closed downward toward the support unit, the movement and vibration transmission between the two can be reduced.

[0028] Preferably, the mechanical damper is a pad made of an elastic material (preferably synthetic rubber or natural rubber).

[0029] In another aspect of the invention, a household appliance, such as a washing machine or kitchen appliance, is disclosed. This appliance includes a drive assembly comprising a motor and a drive shaft connected to the motor, and includes a tool driven by the drive shaft to perform work in use. A sensor is provided, configured to measure characteristics of the drive assembly, and the sensor generates a signal indicative of these characteristics. A processor is provided, configured to identify recurring changes in the characteristics based on the signals received from the sensor, and to control the household appliance based on this identification.

[0030] Any device feature described herein can also be provided as a method feature, and vice versa. As used herein, device plus functional features can alternatively be expressed according to their corresponding architecture, such as a properly programmed processor and associated memory.

[0031] Any feature of one aspect of the invention can be applied to other aspects of the invention in any suitable combination. In particular, a method aspect can be applied to an apparatus aspect, and vice versa. Furthermore, any, some, and / or all features of one aspect can be applied to any, some, and / or all features of any other aspect in any suitable combination.

[0032] Although the invention has been described in the field of household food processing and preparation machinery, it can also be implemented in any field of use where efficient, effective, and convenient preparation and / or processing of materials is desired, whether on an industrial scale and / or in small quantities. Fields of use include the preparation and / or processing of the following substances: chemicals; paints; building materials; clothing materials; agricultural and / or veterinary feed and / or processing agents, including fertilizers, grains, and other agricultural and / or veterinary products; oils; fuels; dyes; cosmetics; plastics; tars; finishing materials; waxes; varnishes; beverages; solders; alloys; effluents; and / or other substances, and any reference to “food” herein may be replaced by such working media.

[0033] The invention described herein can be used in any kitchen appliance and / or as a standalone device. This includes any household food processing and / or preparation machine, including top-driven machines (e.g., countertop mixers) and bottom-driven machines (e.g., blenders). It can be implemented in heating and / or cooling machines. It can be used in machines built into countertops or work surfaces, or in standalone devices. The invention can also be provided as a standalone device.

[0034] As used herein, “food processing” should be considered to include chopping, beating, mixing, kneading, shredding, grinding, shaping, shredding, milling, cooking, freezing, making ice cream, juicing (centrifugal or screw), or other food processing activities, including the physical and / or chemical transformation of food and / or beverage ingredients by mechanical, chemical, and / or thermal means. “Food processing accessories” include, for example, any attachable parts configured to perform any of the aforementioned food processing tasks when rotated and / or powered. Attached Figure Description

[0035] One or more schemes will now be described by way of example only, with reference to the accompanying drawings having the same reference numerals, wherein: Figure 1 This is a side view of a food processing apparatus according to an embodiment of the present invention; Figure 2 yes Figure 1 A top view of the container of a food processing device in a plan view; Figure 3a It is a description Figure 1 A graph of the composite characteristics sensed by the food processing equipment; Figure 3b It is a description Figure 3a The curves of the signal components with composite characteristics; Figure 3c It is a description Figure 3a The curve of another signal component of the composite characteristics; Figure 4 It is shown in Figure 1A schematic diagram illustrating the operation of the algorithm running on the processor of a food processing device; Figure 5 It is shown Figure 4 A schematic diagram of the operation of the processor's filter; Figure 6a It is shown Figure 4 The graph showing the operation of the processor's low-pass filter; and Figure 6b It is shown Figure 4 The graph shows the operation of the processor's notch filter. Detailed Implementation

[0036] Figure 1 An exemplary food processing apparatus 100 according to the present invention is depicted. In this case, the food processing apparatus 100 is a countertop mixer (also known as a kitchen machine), but it should be understood that the invention is equally applicable to other food preparation apparatuses. The term "food processing apparatus" should be understood herein to also cover beverage preparation apparatuses.

[0037] The food processing apparatus 100 has a horizontally extending base 110, at one end of which a container attachment point is formed, to which a bowl-shaped object 200 having a carrying handle 201 can be attached. A support portion 120 extends vertically from the end of the base 110 opposite to the end where the bowl-shaped object 200 is located. The support portion 120 is connected by a hinge 121 to a head 130 supported by the support portion 120. The head 130 extends horizontally away from the support portion 120, extends rearward along the horizontal extension direction of the base 110, and supports a drive outlet 140 that overhangs above the bowl-shaped object 200 on its lower surface. When the head 130 is on the base 110, the hinge 121 allows the head 130 to be lifted away from and lowered toward the bowl-shaped object 200, such that a tool 150, removably attached to the drive outlet 140, is removed from and inserted into the bowl-shaped object 200 by moving upward and downward, respectively.

[0038] To suppress vibration and movement between the head 130 and the support 120, particularly their relative left-right pivoting about hinge 121, a mechanical damper 122 is positioned between them. This damper 122 is preferably made of a vibration-damping elastic material, such as a flexible polymer, like synthetic rubber. The damper 122 may be fixed (e.g., glued) to either or both of the head 130 or the support 120. Alternatively, the damper 122 may be removably attached to either or both of the head 130 and the support 120 using, for example, clips or straps.

[0039] The drive output terminal 140 is preferably a planetary drive output terminal, that is, the drive output terminal drives the tool 150 around its own central axis (by...). Figure 1 The line YY in the diagram represents rotation, and also drives tool 150 (which is eccentrically attached to drive output 140) to rotate around the center of drive output 140 (by...). Figure 1 In this context, line XX represents the line YY (which is offset from but parallel to line YY). To achieve this, the food processor 100 applies rotational drive power from the motor 160 to the drive output 140 via a suitable gear mechanism 170 (e.g., a sun gear arrangement). Figure 1 As shown, the motor 160 can be located directly above the drive output terminal 140, or it can be located within the support portion 120, while providing a suitable drive transmission device (e.g., belt drive or gear system) to transmit drive to the drive output terminal 140. Power is supplied to the motor 160 via a cable connected to mains power or via a battery provided with the food processing apparatus 100.

[0040] To enable user control of the food processing apparatus 100, a user interface 180 is provided on the support portion 120. The user interface 180 may be a control knob, a touchscreen interface, or other form of user interface capable of receiving user commands and providing feedback to the user. A control module 190 is also disposed in the food processing apparatus 100, for example, in the support portion 120, and communicates electronically with the motor 160, the user interface 180, and any other electronic components of the food processing apparatus 100 to receive feedback (including sensor data) from them and send control signals to them. The control module 190 may include suitable memory on which algorithms and routines (including motor control algorithms and routines) can be stored, and suitable processing chips for executing these algorithms and routines. The control module 190 may also include a wireless communication module for communicating with mobile devices and external servers, including, for example, a suitable device control application running on the user's mobile device. The control module 190 may include a general-purpose programmable processor and memory, or it may simply include components arranged on a printed circuit board (PCB) to execute specific pre-arranged routines and algorithms.

[0041] To allow the motor 160 to operate only when the head 130 is lowered toward the support portion 120 and hinged around the hinge 121, a push rod 131 is provided that actuates an interlock switch (not shown) in the support portion. The control module 190 communicates electronically with the interlock switch and allows the motor 160 to be energized only when the switch is actuated.

[0042] The food processing apparatus 100 may include, for example, heating and / or cooling elements in the base portion 110 to heat and / or cool the contents of the bowl 200 when it is attached to the base portion 110. Heating and / or cooling can be controlled using the user interface 160 to achieve a desired temperature, and heating and / or cooling can be automatically controlled by the control module 190 according to routines / algorithms.

[0043] A sensor 161 is provided in electronic communication with the control module 190 to provide sensor feedback. The sensor 161 is associated with the drive output 140 and / or tool 150 and / or motor 161 and / or gear mechanism 170 (collectively, the “drive assembly”) to sense characteristics of its operation. The sensor 161 is preferably a speed sensor (e.g., a Hall sensor that senses the changing magnetic field of an 8-pole toroidal magnet mounted on the drive shaft of the motor as it rotates), which senses the rotational speed of any part of the drive assembly. Direct speed sensing is particularly advantageous because, compared to other characteristics that are proportional to speed but do not always represent the true speed (e.g., the current drawn by the motor), direct speed sensing can inexpensively, simply, and most directly represent the current behavior of the drive assembly. Alternatively, it could be a sensor that measures another characteristic, such as a torque sensor that senses the torque (i.e., torsional force) acting on a part of the drive assembly. An example of such a torque sensor would be a non-contact strain gauge sensor.

[0044] Figure 2 The diagram illustrates an operational scenario of the food processing apparatus 100, where dough being processed by the tool 150 in the bowl 200 has already formed into a block or ball as the tool 150 drives around a circular path r. As the tool 150 moves around the rotational axis xx of the drive output 140, the dough is only located within a portion of the circular trajectory r of the tool 150, and the repeated collisions between the tool 150 and the dough cause periodic variations in the operating characteristics of the food processing apparatus 100. Both the bowl 200 and the tool 150 are preferably dishwasher-safe and made of food-safe materials, such as stainless steel.

[0045] Due to the repeated collisions between the tool 150 and the dough, the speed sensed by the sensor 161 changes periodically. This can be the rotational speed of any element of the drive assembly, including the rotational speed of the tool 150 around its own axis yy or around the rotational axis xx of the drive output terminal 140. Feedback related to this characteristic is transmitted by the sensor 161 to the control module 190.

[0046] Figures 3a to 3c The figures show graphs depicting the effects of different temperatures on food processing machines, such as 100... Figure 2The images show feedback related to time-varying characteristics (in this case, the speed of motor 160) sensed by sensor 161 during dough handling. On the Y-axis, they show the change in the rotational speed W of the drive shaft of motor 160 sensed by a Hall sensor, in revolutions per minute (RPM). Figure 3a and Figure 3b The speed shown is the absolute speed, while Figure 3c The velocities in the figures show the velocity variation relative to the long-term average velocity. On the X-axis, they represent the time t that has elapsed during the mixture, in seconds. Figure 3a The composite signal 300 received by the control module 190 is shown, which consists of the sum of two components (long-period component 301 and short-period repetitive signal component 302).

[0047] like Figure 3b As shown, the long-period component 301 of the composite signal 300 is a long-term variation (e.g., on the order of minutes) and has a relatively large amplitude. The long-period component 301 shows a speed that starts slowly, followed by a relatively rapid increase (e.g., on the order of tens of seconds), and then a relatively slow decrease (on the order of tens of seconds to minutes) asymptotically approaching a specific speed value (e.g., a speed selected by the user using user interface 180). The motor 160 can be controlled by the control module 190 to perform such a long-period speed variation, or it can simply be an overshoot of the motor 160 to a target speed or other such unintentional long-period variation.

[0048] like Figure 3c As shown, the short-period variation component 302 of the composite signal 300 consists of short-period (e.g., second-level or less) velocity variations relative to the long-term average. The short-period component 302 has a higher frequency and lower amplitude than the long-period component 301, and therefore conventional low-pass filtered PID controllers struggle to adapt speed control to compensate for it while still compensating for the long-period variation, as the short-period variation is effectively masked by the larger amplitude of the long-period variation. This short-period variation is undesirable because it can lead to unpleasant noise and vibration, and is caused by the repetitive interaction between the tool 150 and the dough in the bowl 200, as referenced above. Figure 2 As already described.

[0049] To suppress the short-period, low-amplitude velocity change component 302, the control module 190 will... Figure 4 The periodic disturbance suppression (PDR) algorithm 400 shown is applied to its speed control.

[0050] In PDR algorithm 400, an error signal e representing the low-frequency, high-amplitude variation of velocity relative to the target velocity is generated at summation point 401 as input to controller C (which can be a PID controller or other suitable controller). Summation point 401 is obtained from the filtered velocity signal (W┬). The error signal e is generated by subtracting the target speed w' set on, for example, the user interface 180. The error signal e is generated by filter F by applying a filter to the measured speed signal W to remove high-frequency variations. The filter F can, for example, filter out frequencies above 100 Hz and 1000 Hz (preferably around 500 Hz). It can filter out high-frequency variations by applying a gain of 1 to frequencies below 1 / 10 of the filtering frequency (e.g., below 10-100 Hz, and preferably 50 Hz) and a gain of 0.01 at the filtering frequency. The gain can gradually decrease from the frequency where the gain of 1 is applied to the filtered frequency, resulting in a steady increase in the degree of filtering. The controller C then generates a duty cycle control signal v' to compensate for the low-frequency error signal e by, for example, modulating the voltage supplied to the motor control P. In this way, the controller C can compensate for long-period speed variations, such as the long-period speed variation component 301, and this control is unaffected by noise in the measured speed W.

[0051] To accommodate typical short-period, low-amplitude, periodic variations 302, additional processing is required. This is provided by the short-period variation compensator 402, shown by the dashed line. The short-period variation compensator 402 has a measured speed W as its input and includes a filter H and a compensator R.

[0052] like Figure 5 As shown, the measured velocity W is received by an averaging module A, which is equipped with a sampler for sampling the value of W at a specific frequency and a buffer with multiple slots (e.g., at least 5 slots, and preferably between 5 and 100 slots) for temporarily storing and then discarding the sampled values, and generating a moving average across the sampled values. This results in a moving average WAV of the measured velocity over a previous time period (e.g., 1 second). This moving average WAV is then used to tune a notch filter (or a similar band-stop filter) N, which filters out the signal from the measured velocity W within a narrow frequency band.

[0053] The operation of notch filter N is in Figure 6a and Figure 6b The graph depicts the frequency f (in Hertz) along the X-axis and the signal gain along the Y-axis. Here, the frequency represents, for example, the frequency of the change in the magnetic field sensed by the Hall sensor used as sensor 161. Figure 6aThe diagram illustrates a signal that has been fitted with a standard low-pass filter, which filters out high-frequency signals by applying a gain that decreases as the frequency increases after frequency fL. The short-period variation compensator 402 could include such a filter to prevent its output from being affected by high-frequency noise. Figure 6b A frequency band lower than fL is shown, where a notch filter has been applied to signal W at frequency fP, based on the moving average of velocity WAV, and the gain of the signal at this frequency is significantly reduced, whereas signals outside this frequency have a higher gain applied. This results in a perturbation signal d generated by the notch filter. The expected value of fP can be between 1 Hz and 50 Hz, corresponding to the expected time for tool 150 to complete its rotation around bowl 200. As a result of the high or low gain applied to the perturbation signal d, the velocity variation relative to WAV is compensated, and it represents a significant periodic change in velocity. The frequency band representing the velocity band centered at fp and centered at WAV can have a width between 1 Hz and 50 Hz. The notch filter N can apply a gain of 0.01 to 0.0001 within the frequency band centered at fp.

[0054] The compensator R identifies repetitive periodic changes based on the disturbance signal d. For example, the compensator R may include a buffer with more than five slots storing the values ​​of d, which are periodically sampled by a sampler. The compensator R can identify repetitive, regular changes in speed relative to a moving average of the speed and predictively compensate for them. Based on the disturbance signal d, the compensator R generates a compensation signal v'', the value of which will cancel out and reduce the detected periodic changes. A minimum amplitude of d can be set, below which the compensator R does not compensate, or no minimum value can be set. To predictively detect and prevent speed changes of motor 160 before they occur, the disturbance signal d is processed. This processing may include generating the first derivative of the disturbance signal d. Generating the first derivative of d proportional to the motor speed means effectively generating a signal proportional to the motor's acceleration, i.e., a signal proportional to the second derivative of the motor's displacement. Since this represents the motor's acceleration, it can be used to predict the final speed if the acceleration continues. Higher-order derivatives may be generated where appropriate. The compensation signal v'' can then be generated based on this derivative. For example, when the value of d exceeds a certain value (e.g., depending on the task being performed, above 5 RPM, or even above 500 RPM), the derivative can be amplified by a negative gain to offset the increased rate, preferably in the range of -0.01 to -0.0001, or otherwise the gain is zero, so that no compensation signal v'' is generated.

[0055] Other alternative or additional options for signal processing by the compensator R to generate the compensation signal v'' include measuring the period and amplitude between peaks in the disturbance signal d, and generating the compensation signal v'' at a frequency and amplitude configured to counteract the periodic disturbance. For example, the compensation signal v'' could be generated at the same frequency as the frequency at which the peaks in the disturbance occur, with an equal but opposite amplitude, and possibly with an offset to compensate for the time lag when the disturbance is sensed. An example of this would be detecting a periodic deceleration matching the rotation of tool 150 around bowl 200, indicating a recurring impact between tool 150 and the food being processed; in this case, the compensator R would generate an output increasing the motor speed at the same frequency. Again, this approach intervenes in advance, rather than waiting for the periodic disturbance to recur before it is counteracted.

[0056] The maximum value of the compensation signal v'' is preferably limited to between 5% and 50% of the maximum voltage that can be applied to the motor. In this way, excessive load can be avoided.

[0057] Then, at point 403, a compensation signal v'' is added to the duty cycle control signal v' or the compensation signal v'' is subtracted from the duty cycle control signal v' to obtain the true control signal v. For example, if v' is the duty cycle that will cause the motor to overspeed, then v'' will be the negative voltage that will compensate for the overspeed. Both v and v' can be dimensionless signals, representing the percentage of the maximum voltage that must be supplied to the motor by the motor control P.

[0058] The actual control signal v is then applied to the motor control P (e.g., modulating the voltage supplied to the motor) and at least partially compensates for the periodic variations. The motor control P then causes the motor 160 to change its speed, thereby generating a torque tm applied to the dough in the bowl 200. This results in a resistance torque tl, which at point 404 generates the resulting torque t acting on the drive shaft G of the motor 160, and the motor 160 is then sensed to rotate at the resulting speed Wr.

[0059] Although the identification of periodic changes in the characteristics of the drive components according to algorithm 400 has been described as being used to control the speed of motor 160, algorithm 400 can be additionally or alternatively used to control food processing apparatus 100 in different ways. Since the occurrence of periodic changes is caused by the asymmetrical load on motor 160 during each rotation of tool 150 around bowl 200, it can be regarded as an indication of the state of the food being processed therein.

[0060] Examples of foods that can form asymmetric loads include dough that has formed into spheres, ice cream that has solidified into blocks under the action of cooling elements, chocolate that has not yet melted under the influence of heating elements, frosting that has not yet been mixed to form a smooth consistency, and meringue that has not yet been properly mixed. Other things can also be indicated by the occurrence of periodic changes by attaching different tools 150, such as food processing attachments (e.g., slicers or grinders), including repeated cutting of an object by rotating blades, grinding coffee using a disc grinder, asymmetric grinding of meat by a meat grinder's auger, asymmetric juicing of fruit by a screw press, etc. In each case, depending on the food being processed, the occurrence of asymmetric loads can indicate a specific state of the food. The control module 190 can identify the food being processed by user input, by recognizing the food-specific tool 150 attached to it (e.g., in the case of a dough hook attached, the food being processed may be dough), or by using appropriate sensors (e.g., a camera associated with suitable image recognition software, or a chromatograph associated with a pre-stored chemical profile of the food, etc.). It is even possible to identify food products partially or completely from the periodic changes in their properties, where the properties match the specific consistency of a particular ingredient, and to display the identification results to the user.

[0061] Based on the food, the control module 190 can transmit specific states of the food to the user using a user interface 180 or via an application on a mobile device associated with the user (to which the control module 190 communicates wirelessly). For example, the disappearance of a periodic change can indicate that the food being processed has reached a smooth consistency and is therefore ready, and the motor 160 can even stop at that point to avoid overprocessing. In another example, a periodic change can indicate the need for further processing, where processing continues until no more periodic changes are detected. Alternatively, the control module 190 can change the temperature of the bowl 200, for example, by heating to melt any lumps detected within the food being mixed.

[0062] Periodic changes can also indicate information about the status of the food processing apparatus 100 itself or the tools 150 attached to it. For example, it can indicate that the wrong tool 150 is attached, or the absence of such periodic changes can indicate that the food is not being processed by the tool 150. In this case, the control module 190 can notify the user of this as described above.

[0063] Although the aforementioned food processing device 100 has been described as a countertop mixer, the core principles of this invention can be applied to other devices, including beverage makers, coffee grinders, ice cream makers, food processors, handheld mixers, hand blenders, and cooking food processors. In fact, other household appliances, particularly those involving asymmetrical loads (e.g., washing machines), can also benefit from this invention. Washing machines are an example of such machines where noise / vibration from asymmetrical loads is a problem because the clothes being washed may also form "clumps," which the ribs of the washing machine drum periodically encounter, similar to what has been discussed above.

[0064] It should be recognized that the identification of periodic changes relative to the moving average is advantageous compared to existing technical solutions because the system can respond quickly to periodic changes without allowing them to be masked or covered by changes over longer periods with higher amplitudes.

[0065] As used herein, the term "removable attachment" (and similar terms such as "removably attached") used with respect to attachments between a first object and a second object preferably means that the first object is attached to the second object and can be detached (and preferably repeatedly reattached, detached, etc.), and / or the first object can be removed from the second object without damaging either the first or the second object; more preferably, the term means that the first object can be reattached to the second object without damaging either the first or the second object, and / or the first object can be removed from the second object by hand and / or without the use of tools (e.g., screwdrivers, wrenches, etc.) (and optionally also reattached to the second object). In this regard, mechanisms such as snap-fit, bayonet connection, and manually rotatable locking nuts can be used.

[0066] In this context, "food safety" means any substance that, if ingested, would not release substances harmful to human health in clinically significant amounts. For example, it should be BPA-free.

[0067] "Dishwasher safe" means that it should be physically and chemically stable during prolonged exposure to the conditions inside a dishwasher machine. For example, it should be able to withstand exposure to a mixture of water and typical dishwasher substances (e.g., washing with Fairy™ or Finish™ dishwasher tablets and water at 82°C for up to 8 hours without significant degradation (e.g., cracking)).

[0068] It should be understood that the invention has been described above by way of example only, and modifications to the details are possible within the scope of the invention.

[0069] Each feature disclosed in the specification and (where appropriate) the claims and drawings may be provided independently or in any suitable combination.

[0070] Reference numerals appearing in the claims are for illustrative purposes only and should not limit the scope of the claims.

Claims

1. A food processing apparatus (100), comprising: - A drive assembly comprising a motor (160) and a drive shaft connected to the motor (160), and a food processing tool (150) attached to the drive shaft for extending into a food processing container (200) in use for processing food ingredients therein. - A sensor (161) is configured to measure the characteristics of the drive component and generate a signal (300) indicating the characteristics. - A processor (190) is configured to identify repeated changes in the moving average of the characteristic relative to the characteristic based on the signal received from the sensor (161), and to control the food processing apparatus (100) based on the identification.

2. The food processing apparatus according to claim 1, wherein, The characteristic is at least one of the following: - The torque acting on the drive assembly - The speed (W) of the driving component.

3. The food processing apparatus according to any one of the preceding claims, wherein, The processor (190) is configured to control the food processing apparatus (100) to perform at least one of the following: a) The control user interface (180) sends a device status indication to the user. b) Control the user interface to display ingredient type indications to the user. c) Control the user interface to display an indication of the type of food processing tool to the user. d) The wireless communication module of the food processing apparatus controls the transmission of wireless signals indicating the apparatus status to external electronic devices. e) Control the motor to stop. f) Control the motor to change its speed. g) Control the motor to continue running until the repetitive changes stop. h) Control the heating or cooling elements of the food processing apparatus to change the temperature of the container.

4. The food processing apparatus according to any one of the preceding claims, wherein, The frequency of the repetition of the periodic changes is determined by the rotation cycle of the food processing tool within the food processing container.

5. The food processing apparatus according to claim 1, wherein, The processor includes: an averaging module (A) configured to obtain a moving average of the characteristic; and a band-stop filter (N) configured to generate a perturbation signal based on the difference between the characteristic and the moving average, and the processor is configured to generate a control signal for controlling the food processing apparatus based on the perturbation signal (d), preferably wherein the control signal is generated based on the derivative of the perturbation signal.

6. The food processing apparatus according to claim 5, wherein, The control signal is a compensation signal, and the processor further includes a long-period variation controller configured to generate a long-period variation control signal based on sensed long-period variations, and the processor is configured to add the compensation signal to the long-period variation control signal to obtain a true control signal.

7. The food processing apparatus according to claim 6, wherein, The actual control signal is a motor control signal (V), preferably the voltage applied to the motor.

8. The food processing apparatus according to any one of claims 5-7, wherein, The band-stop filter includes a low-pass filter configured to exclude high-frequency noise, preferably a low-pass filter configured to exclude noise at a frequency that is a multiple of the expected maximum value generated by the characteristics due to the expected normal operation of the device, more preferably 10 times the expected maximum value.

9. A method for controlling a food processing apparatus, comprising the following steps: (i) A food processing apparatus having a drive assembly and a food processing tool, the drive assembly including a motor and a drive shaft connected to the motor, the food processing tool being attached to the drive shaft so as to extend into a food processing container in use for processing food ingredients therein. (ii) Measure the characteristics of the drive component and generate a signal based on the measured characteristics. (iii) Calculate the moving average of the stated characteristic. (iv) Identify the periodic changes of the characteristic relative to the moving average. (v) Controlling the food processing apparatus based on the identification.

10. The method according to claim 9, wherein, Step (iv) involves applying a periodic perturbation algorithm to the measured characteristic.

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