Detecting physical parameters

Abstract

A mechanism for estimating a value of a physical parameter at a sensing location. The pulsed electromagnetic wave is received by a sensing element at a sensing location. The sensing element includes a capacitive element and a resistive element connected in a loop. The impedance of the capacitive element and / or the resistive element changes in response to a change in the physical parameter at / near the sensing element. The loop generates an oscillating electromagnetic wave that varies in response to the impedance of the capacitive / resistive element (s), thus in response to the physical parameter. The detection element monitors the oscillating electromagnetic waves to produce an estimate of the physical parameter at the sensing location.

Description

Technical Field

[0001] The present invention relates to the field of monitoring physical parameters, and in particular to remote monitoring of physical parameters. Background Art

[0002] Many cooking and baking devices (such as air fryers) use interactive recipes to ensure that the cooked food is optimally flavored and healthy. For these devices, it is often important to measure or monitor one or more physical parameters of the food item and / or its surroundings. Example parameters include temperature, moisture, humidity, pressure, force, etc. For example, it is often considered important to monitor the temperature of a steak during cooking in order to achieve the desired doneness (e.g., medium, rare, etc.).

[0003] Even in the absence of an interactive recipe, information about such parameters is useful to the operator of the cooking / baking device. For example, providing such information helps the operator control or monitor cooking progress or completion.

[0004] There is a continuing desire to improve the accuracy and flexibility of monitoring one or more parameters of a food or its environment.

[0005] International patent application with publication number WO2021 / 058390A1 discloses a device for sensing the temperature of an object.

[0006] International patent application publication number WO2022 / 072316A1 discloses a cooking appliance having a temperature sensing probe for performing temperature feedback. Summary of the invention

[0007] The invention is defined by the claims.

[0008] According to an example in accordance with one aspect of the present invention, a device for sensing the value of a physical parameter at a sensing location is provided. The device includes: a transmitter element, which is configured to generate and transmit a pulse electromagnetic wave; a sensing element, which is electrically isolated from the transmitter element and configured to be placed at or near the sensing location. The sensing element includes a capacitive element and a resistive element, which are connected in a loop so that in response to the sensing element receiving the pulse electromagnetic wave, the sensing element generates an oscillating electromagnetic wave that changes in response to the impedance of the resistive element. The resistive element is configured so that the impedance of the resistive element changes in response to changes in the physical parameter near the sensing element. The device also includes a detection element, which is electrically isolated from the sensing element and is configured to detect the oscillating electromagnetic wave and process the detected oscillating electromagnetic wave to estimate the value of the physical parameter at the sensing location.

[0009] The present disclosure provides a mechanism for performing remote (short-range) detection of physical parameters at a sensing location (e.g., the location of a food item). A sensing element at the sensing location receives a pulsed electromagnetic wave. The sensing element includes a capacitive element (i.e., a capacitor) and a resistive element (i.e., a resistor), which are connected in a loop, such as side by side with a coil. This generates a resonant signal that oscillates. The oscillation depends on the impedance of the capacitive element and the impedance of the resistive element. At least the impedance of the resistive element (and optionally the capacitive element) is configured to change in response to changes in a physical parameter (e.g., temperature, humidity, strain, pressure, pH value, etc.), so that the oscillation will change. The oscillation generates an oscillating electromagnetic wave, which can be detected by a detection element. Then, the detected oscillation can be processed to derive or determine the value of the physical parameter.

[0010] Thus, the proposed technique provides a mechanism for performing remote detection of a physical parameter at a sensing site located within a device that requires direct power (eg, using a wired power source). This increases the flexibility of placement or use of the sensing element.

[0011] The detection element can be configured to measure the speed or time of decay of the detected oscillating electromagnetic wave, and process the measured speed or time of decay to estimate the value of the parameter at the sensing location. Different speeds or times of decay are associated with different values ​​of the parameter at the sensing location. The speed or time of decay is independent of the signal strength of the oscillating electromagnetic wave, so that accurate determination of the value can be achieved at any distance.

[0012] The detection element can be configured to calculate a time damping constant of the detected oscillating electromagnetic wave, and process the calculated time damping constant to estimate the value of the parameter at the sensing location. Different values ​​of the time damping constant are associated with different values ​​of the parameter at the sensing location. The time damping constant is independent of the signal strength of the oscillating electromagnetic wave, so that accurate determination of the value can be achieved at any distance. The time damping constant is an example of a speed or time measurement of decay.

[0013] The detection element may be configured to integrate the reference signal between two time points defined by the upper or lower envelope of the detected oscillating electromagnetic wave to produce an integrated value of the oscillating electromagnetic wave, and process the integrated value to estimate a parameter value at the sensing location.

[0014] In particular, the time points at which the upper or lower envelope intersects two (different) predetermined thresholds may be identified. The integral value may be generated by integrating the reference signal between these two time points. The integral value is another example of a speed or time measure of decay.

[0015] In some examples, the transmitter element includes a transmitter coil for transmitting pulsed electromagnetic waves; and the detection element includes a detector coil for detecting oscillating electromagnetic waves.

[0016] In some examples, the transmitter coil and the detection coil are formed together by a single coil for transmitting pulsed electromagnetic waves and detecting oscillating electromagnetic waves. This advantageously reduces the number of components required to form the device. This embodiment recognizes that after generating the pulsed electromagnetic wave, the transmitter coil will remain idle during the oscillation of the sensing circuit. Therefore, it has been recognized that the transmitter coil can be reused as a detection coil at this time.

[0017] The resistive element may be a thermistor, such that the physical parameter is temperature. This advantageously provides a temperature sensing system.

[0018] In some examples, the pulsed electromagnetic wave is a square wave pulsed electromagnetic wave. The square wave pulsed electromagnetic wave provides a reliable, repeatable and consistent burst of energy for triggering the oscillation of the sensing element.

[0019] The sensing element may include a sensing coil connected with a capacitive element and a resistive element to form a loop for receiving the pulse electromagnetic wave and outputting an oscillating electromagnetic wave. Using the sensing coil increases the sensitivity of the sensing element to the pulse electromagnetic wave.

[0020] Also proposed is a cooking device comprising any of the apparatus disclosed herein, wherein the sensing element is positioned such that the sensing location is located in or near a food item in the cooking device and / or a food item being cooked (or to be cooked) by the cooking device.

[0021] The cooking apparatus may include a pot for containing food items.

[0022] The transmitter element and the detection element may be positioned outside the pot, and the sensing element may be configured to be housed within the pot.

[0023] Preferably, the pot is non-metallic. Using a non-metallic pot can reduce any attenuation of the pulsed electromagnetic waves or oscillating electromagnetic waves, thereby increasing the signal strength. For example, the pot can be made of ceramic, plastic and / or glass.

[0024] The cooking device may also include a shell and a movable support for supporting the pot, wherein the shell and the movable support are configured so that the movable support can move between the following positions when supporting the pot: a first position, in which any food item contained in the pot is surrounded by the shell, the pot, and the movable support; and a second position, in which the pot is exposed to access any food item contained in the pot.

[0025] In some examples, the transmitter coil and the detector coil, if present, are mounted to a movable support. In some examples, the transmitter coil and the detector coil are integrated into or located on the housing.

[0026] In at least one embodiment, the cookware includes a planar structure configured to support a food item in a cooking device when in use, the planar structure lying in a first plane; and the transmitter coil and the detector coil are positioned to lie in a second plane perpendicular to the first plane.

[0027] These and other aspects will be apparent from and elucidated with reference to the embodiment(s) described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] For a better understanding of the invention, and in order to more clearly show how the same may be put into practice, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0029] Figure 1 The proposed device is illustrated;

[0030] Figure 2 Another proposed device is illustrated;

[0031] Figure 3 A pulsed electrical signal or a pulsed electromagnetic wave is illustrated;

[0032] Figure 4 The diagram shows sensing an electrical signal or an oscillating electromagnetic wave;

[0033] Figure 5 The integral of the envelope of the detected electrical signal is illustrated;

[0034] Figure 6 The proposed cooking device is illustrated;

[0035] Figure 7 A portion of another proposed cooking device is illustrated;

[0036] Figure 8 A first configuration of the transmitter and detector coils of the proposed cooking device is illustrated;

[0037] Fig. 9 illustrates a second configuration of the transmitter and detector coils of the proposed cooking device;

[0038] Fig.10 illustrates the configuration of the emitter-detector coil of the proposed cooking device;

[0039] Fig.11 illustrates another configuration of the transmitter(s) and detector coils of the proposed cooking device; and

[0040] Fig.12 Yet another configuration of the transmitter(s) and detector coils of the proposed cooking device is illustrated. DETAILED DESCRIPTION

[0041] The present invention will be described with reference to the accompanying drawings.

[0042] It should be understood that the detailed description and specific examples indicating exemplary embodiments of the apparatus, system, and method are for illustrative purposes only and are not intended to limit the scope of the invention. These and other features, aspects, and advantages of the apparatus, system, and method of the invention will be better understood from the following description, the appended claims, and the accompanying drawings. It should be understood that the drawings are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used in the drawings to represent the same or similar parts.

[0043] The proposed method provides a mechanism for estimating the value of a physical parameter at a sensing location. A pulsed electromagnetic wave is received by a sensing element at the sensing location. The sensing element includes a capacitive element and a resistive element connected in a loop. The impedance of the resistive element changes in response to changes in the physical parameter at / near the sensing element. The loop generates an oscillating electromagnetic wave that changes in response to the impedance of the resistive element and, therefore, in response to changes in the physical parameter. The detection element monitors the oscillating electromagnetic wave to generate an estimate of the physical parameter at the sensing location.

[0044] Figure 1 A device 100 according to the proposed method is illustrated. The device is designed for sensing a value of a physical parameter at a sensing location.

[0045] The device comprises a transmitter element 110, a sensing element 120 and a detection element 130. In this example, the transmitter element 110 and the detection element 130 are formed as separate, distinct components.

[0046] The transmitter element 110 is configured to generate and transmit pulse electromagnetic waves. More specifically, the transmitter element 110 includes a transmitter coil 111, which acts as an antenna for outputting pulse electromagnetic waves. Any other form of antenna may also be used instead of the transmitter coil 111. The transmitter element also includes a signal generator 112, which generates a pulse (electrical) signal received by the transmitter coil 111. The transmitter coil receives the pulse (electrical) signal and generates a pulse electromagnetic wave.

[0047] The sensing element 120 is electrically isolated from the transmitter element. The sensing element 120 is placed at or near the sensing location. The purpose of the sensing element is to generate an oscillating electromagnetic wave in response to the pulsed electromagnetic wave generated by the transmitter element. More specifically, one or more properties of the oscillating electromagnetic wave change in response to changes in the physical parameter at the sensing location. Therefore, by monitoring the oscillating electromagnetic wave, the value of the physical parameter can be determined.

[0048] To achieve this purpose, the sensing element 120 includes a capacitive element C (e.g., a capacitor) and a resistive element R connected in a loop. The pulsed electromagnetic wave received by the sensing element will thereby oscillate or resonate through the loop formed in the sensing element, thereby generating an oscillating electromagnetic wave. One or more properties of the oscillating electromagnetic wave will change in response to any change in the impedance of the capacitive element and / or the resistive element. At least the impedance of the resistive element and the optional capacitive element is configured to change in response to a change in a physical parameter. In this way, one or more properties of the oscillating electromagnetic wave will change in response to a change in the physical parameter.

[0049] The resistive element is thus configured to change impedance (specifically, resistance) in response to a change in the physical parameter. Preferably, only the resistive element (and not the capacitive element) is configured to change impedance in response to a change in the physical parameter. When designed to do so, the resistance of the resistive element will generally change in proportion to the change in the physical parameter, thereby increasing the convenience of determining the value of the physical parameter.

[0050] In order to improve the sensitivity of the sensing element to the pulsed electromagnetic wave, and to increase the intensity of the oscillating electromagnetic wave, the sensing element 120 may include a sensing coil 121, which is connected to the capacitive element C and the resistive element R in a loop. The sensing coil 121 includes one or more windings or loops around the central axis, and preferably includes a plurality of windings or loops (e.g., at least three). The more windings or loops in the sensing coil, the greater the improvement in the sensitivity of the sensing element to the pulsed electromagnetic wave. The sensing coil 121 acts as an antenna for receiving the pulsed electromagnetic wave and generating the oscillating electromagnetic wave. Any other form of antenna may also be used instead of the sensing coil 121.

[0051] The detection element 130 is electrically isolated from the sensing element 120 and is configured to detect oscillating electromagnetic waves. This can be achieved using a detector coil 131 that detects oscillating electromagnetic waves. The detector coil acts as an antenna to generate an electrical signal in response to the oscillating electromagnetic waves. Any other form of antenna can also be used instead of the detector coil 131.

[0052] The detection element 130 is configured to process the detected oscillating electromagnetic waves to estimate the value of the physical parameter at the sensing location. To this end, the detection element may include a processing circuit 132, which is configured to process the received oscillating electromagnetic waves (e.g., electrical signals generated in response to the oscillating electromagnetic waves) in order to estimate the value of the physical parameter. More specifically, the processing circuit 132 is configured to determine the value of one or more properties of the oscillating electromagnetic waves (i.e., properties that change in response to changes in the physical parameters at the sensing location), and to estimate the value of the physical parameter from these properties. Suitable examples of these procedures will be given later in this disclosure.

[0053] More particularly, the detection element may include a detector coil 131 that generates a detection electrical signal in response to any electromagnetic wave received at the detector coil. This generates the detection electrical signal in response to the oscillating electromagnetic wave. In particular, the amplitude (e.g., voltage) of the detection electrical signal may vary in proportion to the amplitude of the oscillating electromagnetic wave.

[0054] The processing circuit 132 of the sensing element 130 may use analog and / or digital circuitry to process the sensed electrical signal to estimate the value of the physical parameter.

[0055] As previously explained, the resistive element R and optional capacitive element C of the sensing element 120 are configured to change impedance in response to changes in a physical property at the sensing location. A number of suitable examples of suitable capacitive / resistive elements that change impedance in this manner are described below.

[0056] In one example, the resistive element is a thermistor (also known as a resistance thermometer). The resistance of the thermistor will change in response to a temperature change at the sensing location, so that the oscillating electromagnetic wave will change in response to the temperature change. Therefore, the sensed physical parameter can be temperature.

[0057] The capacitive element may be a capacitive temperature sensor, the capacitance of which changes in response to changes in temperature. US Patent No. 4,883,366 provides an example, although other examples are known in the art. In this way, the sensed physical parameter may be temperature.

[0058] In another example, the resistive element is a humistor, i.e. a resistor whose resistance changes in response to humidity. U.S. Patent Nos. US 4,086,556, US 4,464,647 or US 4,751,022 provide suitable examples of humistors. The resistance of the humistor will change in response to changes in humidity at the sensing location, so that the oscillating electromagnetic wave will change in response to the humidity changes. Therefore, the sensed physical parameter can be humidity.

[0059] The capacitive element may be a capacitive humidity sensor. U.S. Patent Nos. US 5,283,711, US 4,651,121 or US 4,164,868 provide examples of such sensors. The capacitance of such a capacitive humidity sensor will change in response to the humidity at the sensing location, so that the oscillating electromagnetic wave will change in response to the change in humidity. Therefore, the sensed physical parameter may be humidity.

[0060] In another example, the resistive element is a strain gauge that changes resistance in response to strain applied to the strain gauge. Thus, the sensed physical parameter can be a measurement of the strain at the sensing location. For example, this can be used to determine a measurement of the weight (e.g., of a placed item) at the sensing location.

[0061] In yet another example, the resistive element may be responsive only to the resistance at the sensing location, e.g., comprising two electrodes to be placed, the resistance between the two electrodes changing in response to the resistance at the resistive location. For example, this may be used to determine or estimate a measurement of moisture content at the sensing location (e.g., moisture content of a placed item) and / or a pH value at the sensing location.

[0062] The examples of potential capacitive or resistive elements that may be used are not exhaustive, and those skilled in the art will readily appreciate that other forms of capacitive and / or resistive elements may be used depending on the desired physical parameter to be detected.

[0063] The values ​​generated by the detection element may need further calibration, mapping or processing to accurately estimate the value of the physical parameter. This can be performed by mapping the values ​​generated by the detection element (e.g., using a lookup table, etc.) to the true value. Other programs may use one or more mapping functions.

[0064] Thus, the sensing element is electrically isolated from the transmitter element and the detection element. This facilitates flexible and wireless positioning of the sensing element away from other elements of the device 100. Avoiding the use of wires to directly power the sensing element advantageously reduces or avoids the need for wires to be connected to the sensing location, for example, wires that might otherwise be worn or damaged during cooking, etc. Thus, more flexible positioning and / or use of the sensing element is achieved.

[0065] Figure 2 An alternative device 200 is illustrated, which is still designed for sensing the value of a physical parameter at a sensing location.

[0066] The device 200 differs from previously described devices in that the emitter element and the detector element are combined into a dual emitter-detector element 210 .

[0067] Thus, the dual emitter-detector element comprises a signal generator 212 for generating an electrical signal which generates a pulsed electromagnetic wave and a processing circuit 213 which processes the electrical signal generated in response to the oscillating electromagnetic wave to determine or derive the value of the physical parameter.

[0068] Of course, the dual transmitter-detector element 210 may include a single coil 211 for transmitting pulsed electromagnetic waves and receiving oscillating electromagnetic waves. This single coil actually represents a combination of the transmitter coil and the detector coil of the previously described embodiment. The coil 211 may be replaced by any other form of antenna.

[0069] The sensing element 220 may be embodied as previously described, for example, including a capacitive element C and a resistive element R connected in a loop, preferably together with a sensing coil 221 .

[0070] In a preferred embodiment, the single coil 211 of the emitter-detector element and the sensing coil 221 are positioned concentrically with respect to each other. This improves the signal-to-noise ratio.

[0071] In a preferred example of any of the devices described herein, all coils of any element are positioned parallel to each other, ie have the same orientation. This improves the signal to noise ratio.

[0072] Any coils or antennas described herein may be formed from any suitable material having suitable electromagnetic properties, such as copper or aluminum.

[0073] Although illustrated in the form of an ellipse or a circle, each coil or antenna may be formed in a different shape, for example, having a square or rectangular cross-sectional shape.

[0074] The following will refer to Figures 3 to 5 A method for estimating a physical parameter value at a sensing location using the proposed technique is described in detail, wherein Figures 3 to 5 Various waveforms are illustrated.

[0075] Figure 3 is a waveform illustrating an exemplary pulsed electromagnetic wave 300 generated by a transmitter element.

[0076] In this example, the pulsed electromagnetic wave is a single square wave pulse. This can be generated by a signal generator that generates a pulsed electrical signal, which is then output in the form of a pulsed electromagnetic wave (eg, via an antenna / coil).

[0077] Therefore, by Figure 3 The waveform shown in the figure may represent the waveform of a pulsed electrical signal (generating a pulsed electromagnetic wave) or the pulsed electromagnetic wave itself.

[0078] Figure 4is a waveform illustrating an exemplary oscillating electromagnetic wave 400 generated by a sensing element in response to a pulsed electromagnetic wave.

[0079] As previously explained, the sensing element includes a capacitive element and a resistive element (optionally, with a sensing coil) connected in a loop. This effectively forms an oscillating circuit. When the pulsed electromagnetic wave is received by the sensing element, the electrical signal ("sensing electrical signal" or "oscillating electrical signal") periodically passes through the loop formed in the sensing ring detection circuit. Each cycle or pass of the loop has less energy, for example, exponential decay. The sensing element thereby generates an oscillating electromagnetic wave that decays over time.

[0080] therefore, Figure 4 The waveform shown in the figure may represent the waveform of the sensed electrical signal in the sensing element loop (generating the oscillating electromagnetic wave) or the oscillating electromagnetic wave itself.

[0081] The decay rate or decay time of the sensed electrical signal and / or oscillating electromagnetic wave will change in response to the impedance of the capacitive and resistive elements, e.g., in proportion. In particular, the amplitude decay rate (over time) will change in proportion to the impedance of the capacitive and resistive elements. For example, the Q factor or quality factor or "half-life" defined from the oscillating electromagnetic wave will change in response to the impedance of the capacitive and resistive elements (and therefore, changes in any physical parameter to be monitored), e.g., in proportion.

[0082] The detection element is configured to receive this oscillating electromagnetic wave, for example, to generate a detection electrical signal in response to the oscillating electromagnetic wave. The detection electrical signal is then processed to determine a measurement or value of the physical parameter. Figure 4 The illustrated waveform may similarly represent the waveform of a detection electrical signal produced by a detection element before the detection element is further processed to estimate the value of the physical parameter.

[0083] In particular, the value of the voltage variation over time of the detection electrical signal is indicative of (eg, proportional to) a measurement or value of the physical parameter.

[0084] In general, the detection element can be configured to generate a value that changes in response to one or more decay parameters of the detection electrical signal. An decay parameter is any parameter that changes in response to the length of time it takes for the detection electrical signal to decay, or the rate of decay. In practice, this represents a measurement of the decay of the oscillating electromagnetic wave in the sensing element.

[0085] As a working example, (a portion of) the upper or lower envelope of the detection electrical signal may be used to define an integration time domain of the detection element (e.g., by an integrating electronic device). In this time domain, integrating the reference signal produces a signal that varies proportionally to the measured value or value of the physical parameter. The portion of the upper or lower envelope may be the portion between two predetermined reference values ​​of the detection electrical signal.

[0086] As another working example, the Q factor of an oscillating electromagnetic wave can be determined from the detected electrical signal. The Q factor will change in proportion to the measured value or value of the physical parameter. The Q factor represents the time damping constant of the detected oscillating electromagnetic wave.

[0087] These two examples provide methods for effectively quantifying or measuring the decay speed or decay time of an oscillating electromagnetic wave generated by a sensing element. Thus, the detection element can be configured to process the detected oscillating electromagnetic wave to estimate a value in response to the decay speed or decay time (e.g., quantify the decay speed or decay time). This value can then be processed to estimate the value of a physical parameter at the sensing location.

[0088] Figure 5 The diagram shows a first waveform 510 and a second waveform 520 generated by integrating a reference signal over a time interval defined by the upper (or lower) envelope of different detection electrical signals generated by different oscillating electromagnetic waves. The value of the signal integrated over the time interval defined by the oscillation envelope is responsive to the decay time of the oscillating electromagnetic wave, and therefore to the impedance of the (one or more) capacitive / resistive element, and therefore to any change in the physical parameter to be monitored.

[0089] More specifically, each waveform can be generated by determining a value representing an exponential decay of the upper / lower envelope of the corresponding detection electrical signal. This can be measured by determining the time interval between two crossings of the detection electrical signal at different reference amplitudes. In order to avoid the use of a timer, a voltage proportional to the time interval can be generated. This can be achieved by integrating a given reference signal along a time interval defined by the detection electrical signal between two predetermined reference amplitudes or values. The predetermined reference values ​​can be associated by a known ratio.

[0090] Thus, each waveform may be determined by time integration over an interval defined by the upper or lower envelope of the corresponding detection electrical signal, which lies between two predetermined amplitude levels of the upper or lower envelope.

[0091] Advantageously, the value of the integration time interval corresponding to the oscillation envelope (or the determined Q factor) between two reference levels will be independent of the amplitude of the oscillating electromagnetic wave. This means that the proposed technique is able to determine or detect the value of the physical parameter even if the signal strength is low and / or the distance between the elements is arbitrary.

[0092] The first waveform 510 and the second waveform 520 are generated by processing detection electrical signals generated using a sensing element (with a thermistor) placed in different temperature environments. The temperature of the environment for generating the first waveform 510 is higher than the temperature of the environment for generating the second waveform 520.

[0093] However, it should be understood that the relationship between the waveform characteristics and temperature (or other measured parameters) will depend on the properties of the capacitive and / or resistive elements. For example, the impedance of some thermistors may increase as the temperature increases, while the impedance of other thermistors may decrease. This will have a corresponding effect on the Q factor of the oscillating electromagnetic wave.

[0094] The processing of the detected electrical signals may be performed using analog processing and / or digital processing.

[0095] In a working example, the detection element may include an analog and / or digital circuit configured to identify the upper envelope of a received oscillating electromagnetic wave; compare the upper envelope with a reference value to identify the crossing of the reference value; calculate the time interval between the crossings of the reference value; express the time interval as a voltage signal and provide a stable output voltage for further processing. The reference value can be related by a known ratio. This method produces an output voltage that changes in response to the Q factor of the oscillating electromagnetic wave, thereby representing a measured value of the physical parameter to be monitored.

[0096] For example, the output voltage may be mapped or correlated to a value of or for a physical parameter, which value may be predetermined using a known quantity or through calibration techniques, for example.

[0097] However, other suitable techniques and methods for extracting a measure of the change in amplitude (of an oscillating electromagnetic wave) over time will be apparent to those skilled in the art.The above technique merely provides one working example of such an approach.

[0098] Any proposed device can be advantageously used in or with a food item processing device such as a cooking device. Examples of cooking devices include air fryers, pressure cookers, rice cookers, halogen ovens, ovens, grills, deep fryers, steamers, stoves, etc. Examples of other food item processing devices include food item processors, blenders, slicers, choppers, grinders, etc.

[0099] Figure 6 An exemplary food item processing device 600 is illustrated, namely a cooking device 600 in the form of an air fryer, which includes the apparatus 100, 200 described herein. The sensing elements 120, 220 are positioned so that the sensing location is in or near the cooking device and / or the food item 690 to be cooked (or being cooked) by the cooking device.

[0100] The cooking device 600 may include a cooking / processing circuit 610 for cooking any food item in the cooking device. Cooking may include controlling the amount of heat provided to the food item, the moisture / water / humidity level provided to the food item, the pressure applied to the food item, etc. A variety of different functions may be used to control the cooking of the food item as will be apparent to those skilled in the art. Preferably, cooking includes at least heating or processing the food item.

[0101] The cooking / processing circuit 610 may be communicatively coupled to the apparatus 100, 200 to receive an estimate of a physical parameter, which here represents a parameter of a food item or a parameter in the vicinity of a food item. The cooking / processing circuit 610 may control the cooking of the food item in response to the estimate. This advantageously provides feedback control of the properties of the food item.

[0102] For example, if the apparatus 100, 200 monitors temperature, the cooking / processing circuitry may be able to use the estimate to monitor the temperature in order to control heating of the food item to or at a particular temperature.

[0103] As another example, if the apparatus 100, 200 monitors pressure near a food item, the cooking / processing circuitry may monitor the pressure using the estimate in order to control or maintain the pressure applied to the food item to or at a particular pressure.

[0104] Of course, the precise control performed by the cooking / processing circuitry 610 (if performed at all) will depend on the capabilities of the cooking / processing circuitry and therefore on the nature / type of the cooking device.

[0105] Methods for controlling the cooking (e.g., heating) of food items in response to monitored physical parameters of the food items or the food item's environment are well established in the art. Non-exhaustive examples include European Patent Nos. EP 3,403,468; EP 3,152,633; EP 3,209,174; EP 3,622,222; EP 3,319,490 or EP 3,993,676; European Patent Application Publication No. EP 3939480A1 or U.S. Patent No. 6,753,027. Various other techniques or procedures will be apparent to the appropriately skilled artisan.

[0106] However, it is not essential that the cooking / processing circuitry controls the cooking of the food item in response to the predicted / estimated value of the physical parameter. Instead, the estimated value may be presented to an operator of the cooking device (e.g., at a user interface) to facilitate manual control of the cooking device, e.g., termination of the cooking process, temperature control, humidity control, etc.

[0107] It will be appreciated that automatic (feedback) control of cooking of a food item using an estimate of a physical parameter and providing a visual representation of the estimate of the physical parameter are not mutually exclusive. Thus, in some examples, a cooking device may be configured to control cooking of a food item using an estimate of a physical parameter and to provide a visual representation of the estimate of the physical parameter, for example, at a display.

[0108] It will therefore be appreciated that cooking apparatus 600 may include a display (not shown) for providing a visual representation of the estimated value of the physical parameter.

[0109] As mentioned previously, it may be necessary to map or further process the values ​​produced by the apparatus 100 , 200 to produce an accurate estimate of the physical parameter. This may be performed by the cooking / processing circuit 610 .

[0110] The cooking apparatus may include a pot 620 for holding food items in the cooking apparatus. In some examples, the pot 620 supports a basket 640 for supporting food items.

[0111] In a preferred example, as shown, the transmitter elements 111, 211 and detection elements 113, 211 of the apparatus 100, 200 are placed outside the pot 620. Of course, the sensing elements 120, 220 are configured to be housed within the pot so that the sensing location is the location of the food item.

[0112] The cooking device 600 may further include a movable support 630 for the pot. The movable support supports the pot and can move the position of the pot, for example, inserting the pot 620 into the cooking device or exposing the pot.

[0113] More specifically, the cooking device may include a housing 650. The housing 650 and the movable support 630 may be configured such that the movable support can move between the following positions when supporting the pot 620: a first position in which any food item contained in the pot is surrounded by the housing, the pot, and the movable support; and a second position in which the pot is exposed to access any food item contained in the pot. The movement between the first position and the second position may be controlled or controllable by an individual.

[0114] This method effectively allows access to the interior of the pot to place the food item (e.g., before cooking) or remove the food item (e.g., after cooking).

[0115] The movable support 630 may include a handle 635 to facilitate movement by an individual.

[0116] Preferably, the pot 630 is non-metallic, for example, made of plastic. This reduces the attenuation of any electromagnetic waves transmitted through the pot, thereby increasing the signal strength of the electromagnetic waves.

[0117] If present, basket 640 is preferably (eg, also) non-metallic, for example, made of plastic. This reduces the attenuation of any electromagnetic waves transmitted to or from the sensing element, thereby increasing the signal strength of the electromagnetic waves.

[0118] In the illustrated example, the pot 620 includes a planar structure 623 that is configured to support a food item in the cooking device during use. The planar structure 623 is configured to be substantially parallel to a horizontal plane (e.g., perpendicular to the direction of gravity) when the cooking device is in use. However, it is not essential that the planar structure actually supports the food item in the cooking device. The planar structure 623 defines a first plane.

[0119] In the illustrated example, the transmitter and detector coil(s) 111, 113, 211 of the apparatus 100, 200 are parallel to the first plane. Thus, the transmitter and detector coils are placed in a substantially horizontal plane.

[0120] The coil(s) may be wound directly around the pot 620 .

[0121] Alternatively and / or in addition, the coil(s) may be mounted to the movable support so that they move with the movable support. In such an embodiment, a specific cable connection may be necessary between the coil(s) and the other element(s) of the device and / or the cooking / processing circuitry that can accommodate changes in position of the movable support without disconnection. The cable connection may be configured to have a spiral and / or harmonica shape. Alternatively, the cable connection may be in the form of a cable reel that automatically extends and / or retracts a length of cable / wire as the movable support moves.

[0122] Figure 7 A portion of a cooking device 700 is illustrated having an alternative arrangement of the transmitter(s) and detector coils 111, 113, 211 for the apparatus 100, 200. The cooking device 700 is otherwise identical to the cooking device 600 described.

[0123] In particular, the transmitter and detector coils 111, 113, 211 can be positioned to lie in a second plane perpendicular to the first plane, i.e., vertically disposed. The coils can be coupled to or positioned on and / or integrated into the housing 650. The vertical orientation of the coils helps achieve this.

[0124] Figure 8 , Fig. 9 and Fig.10 Various configurations and arrangements of transmitter and detector coil(s) 111 , 113 , 211 are illustrated according to different embodiments. Figure 8 , Fig. 9 and Fig.10 Each of provides a cross-sectional top view of the cooking device 700.

[0125] Figure 8 A configuration is illustrated in which the transmitter coil 111 and the detector coil 113 are separate and distinct from each other and are positioned to occupy a single side of the housing. For example, the coils may be positioned on (a portion of) the left wall and (a portion of) the right wall of the housing 650, respectively. The two coils are placed in respective planes and are positioned parallel to each other.

[0126] Each coil can be replaced by another form of antenna.

[0127] Fig. 9 An alternative configuration is illustrated in which the transmitter coil 111 and the detector coil 113 are separate and distinct from each other, but the location of each coil extends to more than one side of the housing. For example, the transmitter coil may be placed on (part of) the left wall and (part of) the back wall of the housing, while the detector coil may be placed on (part of) the right wall and (part of) the back wall of the housing. This increases the range of the coil(s) to improve reliability. Each coil may be replaced with another form of antenna.

[0128] Fig.10 Another alternative configuration is illustrated in which the transmitter coil and the detector coil are formed from a single coil 211. The single coil 211 surrounds three sides of the pot 620. The coil may be replaced by another form of antenna.

[0129] exist Figure 8 , Fig. 9 and Fig.10 In all the illustrated embodiments, the coil(s) are integrated into the housing. In other examples, the coil may be placed on the housing, for example, between the housing 650 and the pot 620.

[0130] Fig.10 and Fig.11 A variation is illustrated in which the transmitter and detector coils 111, 113, 211 are placed around the pot 620. In particular, the coil(s) are placed on a movable support 630 to surround the pot, which is also in Figure 6 is shown in the figure.

[0131] The movable support 630 is configured to move along one or more tracks 1200 so as to be in a first position (eg, Fig.10 ) and a second position (as shown in Fig.11 620 and the movable support 630. In the first position, the housing 650, the pot 620 and the movable support 630 surround any food items contained in the pot. In the second position, any food items contained in the pot are contained, for example, for the operator of the cooking device 600 to take.

[0132] As explained previously, the transmitter coil and the detector coil 111, 113, 211 may be formed by separate dedicated coils. Alternatively, the transmitter coil and the detector coil may be formed by a single coil.

[0133] The skilled person will understand how the proposed device can be adapted to other forms of food item processing equipment. In general, the proposed device can be used to determine the measured values ​​of parameters near a food item to be processed or being processed (e.g., cooking, chopping, slicing, etc.). The determined measured values ​​can be used to control the operation of the food item processing equipment, for example, to achieve the desired food item processing results (e.g., the desired cooking results or slicing results). In particular, the determined measured values ​​can be used as feedback to control parameters during food item processing. As another example, the determined measured values ​​can be displayed on a display. As another example, the determined measured values ​​can be provided to another processing device for further processing, for example, to determine future cooking / processing parameters, etc.

[0134] Those skilled in the art can understand and implement variations to the disclosed embodiments when practicing the claimed invention by studying the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0135] The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0136] If the term "suitable for" is used in the claims or the specification, it should be noted that the term "suitable for" is intended to be equivalent to the term "configured to".

[0137] Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. An apparatus (100, 200) for sensing a value of a physical parameter at a sensing location, the apparatus comprising: a transmitter element (110, 210) configured to generate and transmit a pulsed electromagnetic wave (300); a sensing element (120, 220) electrically isolated from the transmitter element and configured to be positioned at or near the sensing location, wherein: The sensing element comprises a capacitive element (C) and a resistive element (R), the capacitive element and the resistive element being connected in a loop so that in response to the sensing element receiving the pulsed electromagnetic wave, the sensing element generates an oscillating electromagnetic wave (400), the oscillating electromagnetic wave changes in response to the impedance of the resistive element; and The resistive element is configured such that an impedance of the resistive element changes in response to a change in the physical parameter in the vicinity of the sensing element; as well as A detection element (130, 210) is electrically isolated from the sensing element and is configured to detect the oscillating electromagnetic wave and process the detected oscillating electromagnetic wave to estimate a value of the physical parameter at the sensing location.

2. The device (100, 200) according to claim 1, wherein the detection element is configured to calculate a time damping constant of the detected oscillating electromagnetic wave and process the calculated time damping constant to estimate the value of the parameter at the sensing location.

3. An apparatus (100, 200) according to claim 1 or 2, wherein the detection element (130, 210) is configured to integrate a reference signal between two time points defined by an upper envelope or a lower envelope of the detected oscillating electromagnetic wave to produce an integrated value for the oscillating electromagnetic wave, and to process the integrated value to estimate the value of the parameter at the sensing location.

4. The device (100, 200) according to any one of claims 1 to 3, wherein: The transmitter element (110, 210) comprises a transmitter coil (111, 211) for transmitting the pulsed electromagnetic wave; and The detection element (130, 210) comprises a detector coil (131, 211) for detecting the oscillating electromagnetic wave.

5. The device (200) according to claim 4, wherein the transmitter coil and the detection coil are together formed by a single coil (211), the single coil being used to transmit the pulsed electromagnetic waves and to detect the oscillating electromagnetic waves.

6. The device (100, 200) according to any one of claims 1 to 5, wherein the resistive element (R) is a thermistor, so that the physical parameter is temperature.

7. The device (100, 200) according to any one of claims 1 to 6, wherein the pulsed electromagnetic wave (300) is a square-wave pulsed electromagnetic wave.

8. The device (100, 200) according to any one of claims 1 to 7, wherein the sensing element (120, 220) comprises a sensing coil (221), and the sensing coil (221) is connected to the capacitive element and the resistive element to form a loop for receiving the pulsed electromagnetic wave and outputting the oscillating electromagnetic wave.

9. A cooking device (600) comprising the apparatus according to any one of claims 1 to 8, wherein the sensing element (120, 220) is positioned so that the sensing location is located in or near a food item (690) in the cooking device.

10. The cooking device (600) according to claim 9, comprising a pot (620) for containing the food item, The transmitter element (111, 113, 121) and the detection element are positioned outside the pot, and the sensing element (120, 220) is configured to be received within the pot.

11. The cooking device (600) of claim 10, wherein the pot (620) is non-metallic.

12. The cooking device (600) according to claim 10 or 11, comprising a housing (650) and a movable support (630) for supporting the pot, wherein the housing and the movable support are configured such that the movable support can move between the following positions when supporting the pot: a first position in which any food item contained in the pot is surrounded by the housing, the pot, and the movable support; and and a second position in which the pot is exposed to provide access to any food item contained in the pot.

13. A cooking device (600) according to claim 12, when dependent on claim 4, wherein the transmitter coil (111, 211) and the detector coil (131, 211) are mounted to the movable support.

14. The cooking device (600) of claim 12, when dependent on claim 4, wherein the transmitter coil (111, 211) and the detector coil (131, 211) are integrated into or positioned on the housing.

15. The cooking device (600) according to any one of claims 10 to 14, wherein: the pot comprises a planar structure configured, in use, to support the food item in the cooking apparatus, the planar structure lying in a first plane; and The transmitter coil and the detector coil are positioned to lie in a second plane, the second plane being perpendicular to the first plane.

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