EP2380393B2 - Intelligent food preparation device - Google Patents

Description

The invention relates to an attachment for food preparation, in particular cookware, with a transmitter and an energy absorber for powering the transmitter and an operating device for operating the attachment for food preparation.

EP 0 098 491 A2 discloses a remote measuring device which has at least one interrogation station and at least one measuring station, which are equipped with at least one information transmitter or modulator and with one information receiver and one antenna each. The measuring station is provided with a measuring device for carrying out the measurements. The interrogation station is equipped with an energy transmitter that emits the energy required for the measuring station. The measuring station has an energy receiver, which is followed by a rectifier that is provided for the entire current or voltage supply of the measuring station. If several measuring stations are to transmit their measured values to an interrogation station at the same time, each measuring station is provided with an additional memory which contains a special opening code. The addressed measuring station only provides its information if the opening code sent by the interrogation station matches the opening code contained in the memory. The measuring station can have a microcomputer belonging to a signal processing and control unit of the measuring station. Measurement data processed by the microcomputer reach the modulator via its output in the form of a control signal, which is connected downstream of the microcomputer and which is connected to the antenna. The modulator changes the resistance of the antenna according to the signal fed to it. The measuring station can be accommodated in a knob of a lid of a cooking container.

EP 1 037 508 A1 discloses an inductive cooker for heating food to be cooked, which contains means for controlling the heat output and at least one sensor for measuring the temperature. The output signal from the sensors is used as a manipulated variable for the control means. The sensors are attached directly in or near the food to be cooked. The output signal from the sensors is displayed visually using a display unit on the inductive cooker.

WO 99/41950 A2 discloses a cooking utensil for use with induction cooktops that includes all of the input elements for controlling the induction heating in, for example, a handle of the cooking utensil. Power is obtained by converting ELF radiation used to heat the cookware and the control knobs, temperature sensing means and transmission means to the power control unit for the induction coils all fit within the handle.

US 3,742,178 A1 discloses an induction cooker with a shelf that supports cookware containing food. The dishes are heated by the cooker's induction coil, which operates at a high frequency. The induction cooking range includes a temperature sensing unit having a temperature detecting unit and a temperature receiving unit. The former unit is built into the cookware, while the latter unit is remote from it in the induction cooker. The aforesaid temperature receiving unit receives radio frequency transmissions of temperature data from the temperature sensing unit in the harness. The temperature sensing unit in the dishes is powered by the main field generated by the induction coil.

U.S. 6,504,135 B2 discloses temperature self-regulating food delivery systems having magnetic induction heating and an associated food container equipped with a substantially permanent ferromagnetic heating element. The induction heater and heating elements are designed to heat the heating element to a user-selected control temperature when the heating elements are coupled to the heater's magnetic field, and the temperature is maintained near the control temperature indefinitely. The temperature control is adjusted by periodically determining at least two parameters of the resonant heating circuits of the induction heating based on the amplitude of the resonant current flowing through during heating. The value of the resonant circuit amplitude and the rate of change of the amplitude are preferably determined.

DE19743253A1 discloses a method for protecting circuit components of an integrated circuit against excessive operating temperatures and a correspondingly designed protective circuit.

It is the object of the present invention to provide a possibility for efficient, flexible and fail-safe communication between a food preparation attachment and an operating device set up for its operation.

This object is achieved by means of a food preparation attachment according to claim 1 and an operating device for operating the food preparation attachment according to claim 12. Preferred embodiments can be found in particular in the dependent claims.

The food preparation attachment has at least one transmitter for the wireless transmission of data to an external unit. A transmitter is generally understood to mean a transmission device for access to a transmission channel to an external unit. The food preparation attachment also has at least one integrated circuit for processing data and for outputting data to the transmitter based on processing. The integrated circuit can thus process data, e.g. B. read, change, link, cache, format, etc., and output this data or data derived from it to the transmitter for transmission to an external unit. Data to be processed can be sent from another entity, e.g. B. a sensor, be supplied data or data stored in or on the integrated circuit, z. B. an identifier or property of the food preparation attachment. The transmitter of the food preparation attachment is not battery operated, but draws its energy essentially from an electromagnetic excitation field. For this purpose, the food preparation attachment has at least one energy absorber for the continuous absorption of energy from the electromagnetic excitation field. Energy absorbed from the electromagnetic excitation field is used to power the cooking appliance (operation of a heating element, etc.) and is also used to feed at least the integrated circuit and the transmitter, and possibly other low-voltage components. The heating element can therefore be supplied with energy for its operation by means of the at least one energy absorber. For this purpose, the energy absorber can be followed by a switching regulator, which rectifies energy decoupled from the power supply to a voltage level suitable for operating the low-voltage components. In other words, the food preparation attachment including the heating element as well as the integrated circuit and the transmitter are powered by the energy absorber for their operation.

The integrated circuit can thus be provided with a high level of electrical power over the long term, which enables the use of particularly powerful and comparatively inexpensive electronic components. To protect against short power interruptions, energy storage devices can be present, e.g. B. powerful capacitors such as gold caps. By using a powerful integrated circuit, the scope of the transmitted data can be significantly higher than, for example, with RFID (radio tag) systems without their own power supply or even with low-energy electronics. Data can also be processed flexibly. For example, the use of a powerful integrated circuit enables intelligent power management of the operational performance depending on the food preparation device and process parameters of the attached devices, e.g. B. a power distribution to several energy transfer areas (z. B. cooking zones) depending on a maximum power consumption of the attached devices. Furthermore, electronic components are available for higher temperatures than RFIDs, which increases reliability.

The integrated circuit can be in the form of an analog integrated circuit, a digital integrated circuit or a mixed analog and digital integrated circuit (“mixed signal IC”). The integrated circuit can be configured as an ASIC, DSP, FPGA, or microcontroller, for example. The integrated circuit can have a data memory and/or be connected to a data memory, e.g. B. an EEPROM.

The food preparation attachment also has a self-temperature determination unit for determining a self-temperature of the integrated circuit. The integrated circuit is set up to process intrinsic temperature data determined by the intrinsic temperature determination unit and to output the intrinsic temperature data to the transmitter based on the processing of the intrinsic temperature data. As a result, temperature values that are harmful to the operation of the integrated circuit can be detected early and subsequently avoided.

The energy absorber has a coil with corresponding power windings, in particular for tapping off energy from an electromagnetic excitation field in the form of an alternating magnetic field. By using a coil as an energy absorber, the food preparation attachment can be used in particular for inductive or transformer energy transmission (energy transmission between two inductors using an alternating magnetic field), in which the electromagnetic excitation field is generated using an external primary coil. The principle of the transformational energy transfer is, for example, in DE 10 2006 017 800 A1 described.

The transmitter can be at least partially integrated into the integrated circuit. This achieves a particularly compact design. Alternatively, the transmitter is a separate device from the integrated circuit.

The transmitter can have a modulator and an antenna connected downstream of the modulator. With such a construction of the transmitter, for example, the modulator may be integrated into the integrated circuit, but not the antenna.

The modulator can modulate the data signals by means of amplitude shift keying (ASK) onto a carrier signal for wireless transmission of the modulated carrier signal via the antenna. So-called "on-off keying" (OOK) can be used as a particularly simple form of amplitude shift keying, but several amplitude values (levels) can also be selected. Other possible, preferably digital, types of modulation can be, for example, frequency shift keying (FSK, e.g. in the form of "Gaussian Minimum Shift Keying", GMSK) and phase shift keying (PSK, e.g in the form of a binary phase modulation, BPSK, or a quadrature amplitude modulation, QPSK) Multi-carrier methods such as orthogonal frequency division multiplex, OFDM, or coded orthogonal frequency division multiplex, COFDM, can also be used.

The data is advantageously transmitted using a high-frequency carrier signal, with a frequency difference between the carrier signal and a frequency of the electromagnetic excitation field for feeding the food preparation attachment being selected such that the frequencies of energy transmission (power transmission) and signal transmission do not interfere with one another. This is advantageously done taking into account an interference spectrum of the energy transmission. The power transmission is preferably in a range between 0 kW and 4 kW.

The antenna can be embodied as a coil-like winding(s), particularly in the case of a transformer energy transmission, since the operating device and the attachment for food preparation are already set up there for an inductive coupling via corresponding coils and already have a sufficiently small distance. The signal transmission can be carried over the same windings over which the power is transmitted, e.g. B. from a secondary coil to the primary coil in unidirectional data transmission and between the two coils in bidirectional data transmission. This eliminates the need for a separate antenna. To reduce the susceptibility to faults, the signal can be transmitted via inductively coupled signal windings in the operating device and food preparation attachment, which are designed separately from the power windings for power transmission. The signal winding(s) may in particular be coplanar with the power windings, e.g. B. the power turns on the outside circumferentially. In general, however, the data can also be transmitted in other ways, e.g. B. over a radio air link, an optical data transmission channel, an IR data transmission channel and so on.

The processor clock of the integrated circuit can advantageously serve as the carrier frequency.

The food preparation set-top box can be equipped with only one transmitter, which simplifies the construction of the food preparation set-top unit and reduces the cost (simplification of the electronics of the food preparation set-top unit). The communication is then unidirectional from the food preparation attachment to the operating device (base station).

However, the food preparation attachment can also have a receiver function for particularly flexible treatment of the food to be cooked. Communication can then take place bidirectionally between the food preparation attachment and the operating device. The food preparation attachment can be equipped with a separate receiver (receiver). The receiver can then have a demodulator connected downstream of a receiving antenna, it also being possible for the demodulator to be integrated into the integrated circuit. In order to save on components, the transmitter can advantageously be designed as a transceiver (transmitter/receiver). The transceiver can have a modem connected downstream of a transmit/receive antenna, it also being possible for the modem to be integrated into the integrated circuit. The data received can be processed by the integrated circuit in the food preparation attachment.

The data transmission from the food preparation attachment to the operating device can, for example, be initiated cyclically and/or upon request of the operating device in the case of bidirectional data transmission, but not upon request in the case of unidirectional data transmission. In the case of bidirectional data transmission, some data (e.g. measurement data or device status data) can also be transmitted cyclically and other data (e.g. identification data) can be transmitted on request from the food preparation attachment.

For bidirectional communication, modems can be present both on the operating device and on the food preparation attachment. A modulator on the food preparation attachment and a demodulator on the operating device are sufficient for bidirectional communication.

Data can be exchanged both in full duplex mode and in half duplex mode.

The food preparation attachment can also have at least one sensor unit for sensing at least one physical measured variable, the at least one integrated circuit being set up to process sensor data from the at least one sensor unit and to output data to the transmitter based on this processing. In particular, a measured variable can be sensed as a physical measured variable which is used to set or control a cooking process, such as the temperature of the food to be cooked, a pressure (e.g. in a pressure cooker), a moisture content, a fill level and so on. A corresponding temperature control, pressure control, humidity control, etc. is made possible by transmitting the physical measured variable(s).

However, other data can also be output from the integrated circuit via the transmitter to the outside, such as identification data for identifying the attached device and/or device status data about a device status. The identification data can, for example, contain information about a device type (e.g. pot, pan, small household appliance), a system affiliation (e.g. to a specific series of devices), a design, a type and number of sensors, control parameters, material properties (e.g. B. a thermal conductivity of a cookware bottom), coefficients (z. B. PID coefficients for a PID control) etc. of the food preparation attachment include. The device status data can contain, for example, information about a device's presence, an on/off state, a power consumption, a centering of the food preparation attachment with respect to a power transmission area (cooking zone or the like), and so on. For example, the information about the centering of the food preparation attachment can be used to readjust the energy transmission when the pot is not centered enable or be used for efficient energy transfer (adjustment of the parameters of the electromagnetic excitation field). It is also possible to adapt the power control to an attached food preparation attachment depending on the identification data (properties of the food preparation attachment, etc.) and/or device status data. A user interface of the operating device can also be individually adapted to the food preparation attachment using the identification data.

In general, the transmitted data, in particular the measurement data, can be used to identify food states, such as the cooking states of cooking utensils or the end of food preparation with a toaster (toast ready) or a coffee machine (coffee has run through), etc. The data transmission also enables cooking programs to be carried out possible for different foods.

In order to sense an inherent temperature of the integrated circuit, the inherent temperature determination unit can have an (inherent) temperature sensor. This can be arranged outside the integrated circuit, e.g. B. in a region of space representative for determining the intrinsic temperature (e.g. on a surface of the integrated circuit or at some distance from it), and connected to the integrated circuit. Alternatively or additionally, the intrinsic temperature determination unit can be integrated in the integrated circuit; the intrinsic temperature sensor does not need to be a separate sensor, but can also determine the temperature indirectly, e.g. B. via a temperature-dependent runtime determination, voltage level determination, resistance value determination, clock rate determination, etc.). In general, a self-temperature determination unit is understood to be a unit that is able to infer the self-temperature from a sensed primary variable (voltage, resistance, etc.).

The processing of the inherent temperature data takes place in the integrated circuit, in the operating device or partly in the integrated circuit and partly in the operating device. In particular, the integrated circuit can process the intrinsic temperature data for transmission to the operating device, e.g. B. Format while the control gear uses the intrinsic temperature data to control the food preparation attachment.

The processing of the intrinsic temperature data can include a comparison of the intrinsic temperature with at least one intrinsic temperature threshold value. The intrinsic temperature threshold value can be predetermined, for example, and stored in a memory connected to the integrated circuit or integrated therein. Depending on the fact that a self-temperature threshold has been reached or exceeded and, if applicable, which of several self-temperature thresholds has been reached or exceeded, a warning can be issued, the excitation field can be specifically weakened and, in extreme cases, even switched off.

In particular, the intrinsic temperature can be compared to a number of intrinsic temperature threshold values, and different actions can be taken depending on the level of the threshold value. For example, in the event that the processing of the intrinsic temperature data takes place in the operating device, if the intrinsic temperature value transmitted by the food preparation attachment reaches or exceeds a first, lower intrinsic temperature threshold value coming from below, the operating device can emit an acoustic and/or optical warning signal output that indicates the critical condition to an operator and can prompt him to take countermeasures. Reaching or exceeding the first, lower intrinsic temperature threshold value can be an indication of a low water level in a cooking utensil ('threatening to boil empty'), to which the operator can react, for example, by refilling the cooking utensil with water. In addition to the warning signal, the operating device causes the electromagnetic excitation field to be reduced by 25%, for example, in order to prevent overheating and an interruption in the cooking process. If the intrinsic temperature value reaches or exceeds a second, higher intrinsic temperature threshold value (e.g. after boiling dry for a long time), the operating device switches off the excitation field in order to prevent damage to the integrated circuit (and possibly other temperature-sensitive components).

Also, different intrinsic temperature thresholds may be associated with different levels of reduction (e.g., a 5%, 10%, 25%, etc. reduction) in the strength of the excitation field. In this case, the reduction can turn out to be all the greater, the higher the self-temperature threshold value that has been reached or exceeded.

In general, certain reactions can also be reversed when the intrinsic temperature decreases, e.g. B. the warning signal can be switched off when the lower threshold value is reached and/or a higher strength, e.g. B. the full strength of the excitation field can be adjusted.

In the event that the processing of the intrinsic temperature data takes place in the integrated circuit, if the intrinsic temperature reaches or exceeds the intrinsic temperature threshold value, the integrated circuit can output a corresponding intrinsic temperature threshold exceeded signal to the transmitter. Such an intrinsic temperature threshold exceeding signal can include a warning signal, a turn-down signal for reducing the electromagnetic excitation field and/or a switch-off signal for switching off the electromagnetic excitation field.

The food preparation attachment can be designed in particular as a cooking utensil, z. B. as a pot, pan, etc.

The operating device is set up to operate such a food preparation attachment and for this purpose has at least one excitation field generating means, in particular a coil ('primary coil') for transformative energy transmission, in order to generate an electromagnetic excitation field, in particular an alternating magnetic field. The operating device has a receiver which is set up to receive data from the transmitter of the food preparation attachment. The operating device also has a control unit for adjusting a strength of the excitation electromagnetic field based on the received data.

The control unit is also set up to carry out a comparison of the intrinsic temperature with at least one intrinsic temperature threshold value when intrinsic temperature data is received.

If the intrinsic temperature reaches or exceeds an intrinsic temperature threshold value, the operating device can then give a warning signal and/or reduce a strength of the electromagnetic excitation field, including switching off.

The operating device can reduce a strength of the electromagnetic excitation field depending on a level of one of a plurality of self-temperature threshold values.

However, the control unit can also be set up to react accordingly when it receives a signal that it has exceeded its own temperature threshold value. In particular, the control unit can (a) output a visual and/or acoustic warning when receiving a warning signal from the food preparation attachment, (b) reduce the electromagnetic excitation field when receiving a down regulation signal, in particular regulate it down, and/or (c) when receiving a switch-off signal the switch off the electromagnetic excitation field. The control unit can thus counteract an impending overheating of the integrated circuit.

In order to prevent the attachment device from heating up, it is preferred if a power of no more than 10 watts is consumed for data communication, specifically no more than 5 watts, in particular no more than 3 watts. In this case, the power can also be required to operate an electronic system of the add-on device, which uses the signal coil as an antenna.

To suppress crosstalk between a power signal and a data signal, it is preferred if a minimum frequency of the power signal or the data signal is at least ten times higher than a maximum frequency of the data signal or the power signal. The data signal can preferably have a frequency in the MHz range or higher, preferably in a range from a frequency of 4 MHz or z. B. a frequency in the frequency range between 4 MHz and 32 MHz.

The power signal advantageously has a frequency of no more than 400 KHz, in particular a frequency in the frequency range between 100 KHz and 400 KHz. Alternatively or additionally, data signals may be transmitted at frequencies below the power transmission frequency band.

In order to prevent the attachment device from heating up, it is preferred if a power of no more than 10 watts is consumed for data communication, specifically no more than 5 watts, in particular no more than 3 watts. In this case, the power can also be required to operate an electronic system of the add-on device, which uses the signal coil as an antenna.

A method for operating such a food preparation attachment can, for example, have the following steps: monitoring an intrinsic temperature (by means of the integrated circuit of the food preparation attachment and/or by means of the operating device) and, if the intrinsic temperature reaches or exceeds a predetermined intrinsic temperature threshold value, outputting a Warning signal and / or turning down (if necessary including switching off) the electromagnetic excitation field.

Fig. 1

zeigt ein System aus einem Betriebsgerät zum Betreiben eines Gargeschirrs mittels transformatorischer Energieübertragung und einem darauf angeordneten Topf als Gargeschirr;

Fig. 2

zeigt eine Skizze einer vereinfachten Regelstruktur des Systems aus Fig. 1.

In the following figures, the invention is described schematically in more detail using an exemplary embodiment. For the sake of clarity, elements that are the same or have the same effect can be provided with the same reference symbols.

1

shows a system consisting of an operating device for operating a cooking utensil by means of transformer energy transmission and a pot arranged thereon as cooking utensil;

2

shows a sketch of a simplified control structure of the system 1 .

1 shows an intelligent cooking utensil 101, which is designed as an "electric pot and represents an electrical consumer. The cooking utensil 101 has a base body 102 with a lid and handles and an energy absorber 114 designed as a drive unit. The cooking utensil 101 is on a surface of a worktop 105 an operating device 106 for operating the cooking utensil 101. An energy transmission unit 107 is mounted under the worktop 105. It has a housing 108 with an actuating element 109 for switching the energy transmission unit 107 on and off and a power generation unit 112 for supplying an alternating current to the excitation field generation means 111. In this exemplary embodiment, the power generation unit 112 is designed as an inverter Field generating agent 111 is wound in the form of a spiral coil. When operating the power transmission unit 107 and the pot 101, the excitation field generating means 111 is fed with the alternating current and generates an excitation field designed as an alternating magnetic field. By means of a field flux of this excitation field, the excitation field generating means 111 transmits energy to the energy absorber 114 by induction, which is arranged in an energy transmission area 113 drawn on the surface of the worktop 105 . The energy absorber 114 is designed as a secondary winding which is wound in the form of a spiral winding. The energy transfer area 113 is indicated by a line 115 on the worktop 105 . A secondary voltage is induced in the energy absorber 114 by the excitation field flow, which is used as the operating voltage for operating the cooking utensil 101 . The cooking utensil 101 can be removed from the transmission area 113, as a result of which the energy absorber 114 is separated from the excitation field generating means 111. In the transmission area 113 then more electrical consumers can be brought such. B. a coffee maker, a blender, a charger, a fryer, a toaster, a kettle, etc. (also referred to as 'small household appliances'), each of which has an energy absorber and obtain operating energy from a wireless interaction of the respective energy absorber with the excitation field generating means 111 .

In addition, a control panel in the form of a touch-sensitive screen 104 is embedded in the worktop 105, on which display elements and actuating elements can be freely programmed. The touch-sensitive screen 104 can be, for example, a liquid crystal or LED screen covered by a touch-sensitive film, e.g. B. an ITO film is covered. As a result, a large number of different actuating elements such as buttons, circular sliders, linear sliders can be displayed essentially arbitrarily on the control panel, which allows for very flexible operator guidance.

The cooking utensil 101 is equipped with an integrated circuit 116 for processing data and for outputting data to a transmitter. A temperature sensor (inherent temperature sensor) 117 for determining an inherent temperature of the integrated circuit 116 is connected to an input of the integrated circuit 116 . The integrated circuit 116 cyclically senses the intrinsic temperature sensor 117, processes the sensed intrinsic temperature signals into a predetermined data and protocol structure, and transmits the intrinsic temperature data so processed to a transmitter. The transmitter has a modulator (not shown) and a downstream transmission antenna. The secondary winding 114 is used here as a transmitting antenna for power transmission. The data signals emitted by the secondary winding 114 are received by the primary winding 111, which also serves as a receiving antenna of the operating device 106, are demodulated in a demodulator (not shown) of the operating device 106 and forwarded to a control unit 110 of the operating device 106. The control unit ("oven electronics") 110, which here comprises a microcontroller, controls the power generation unit 112 using the intrinsic temperature data, among other things.

When the transmitted value of the intrinsic temperature reaches or exceeds a first, lower intrinsic temperature threshold value coming from below, the control unit 110 emits an acoustic and optical warning signal that indicates a critical condition to an operator and can prompt him to take countermeasures. Reaching or exceeding the first intrinsic temperature threshold value can be an indication of a low water level ('threatening to boil empty'), to which the operator can react, for example, by refilling water, switching down a power level or removing the cookware. In addition to the warning signal, the control unit 110 causes the electromagnetic excitation field to be reduced by, for example, 25% ("reduction level") in order to prevent overheating and an interruption in the cooking process. If the intrinsic temperature value reaches or exceeds a second, higher intrinsic temperature threshold value (e.g. after boiling dry for a long time), the control unit 110 switches off the power generation unit 112 and thus the excitation field in order to prevent damage to the integrated circuit (and possibly other temperature-sensitive components). to prevent.

2 shows a sketch of a simplified control structure of a system consisting of an intelligent cooking utensil 201 and an operating device 206.

The intelligent cooking utensil 201 is in the form of a pot in which food 221 to be cooked can be placed in a base body 202 which is closed off at the bottom by a pot base 220 . A heating track 222 in the form of an intertwined resistance thick-film track runs on the underside of the pot base 220 , which is heated up when energized and thus heats up the pot base 220 to heat the food 221 to be cooked. For its power supply, the heating track 222 is connected to an energy absorber 214 in the form of a spiral-shaped secondary winding and represents its load. For this purpose, the electronic pot 223 has a switching regulator 224, which converts the AC power voltage output by the energy absorber 214 into a low-voltage DC voltage. The remaining parts of the pot electronics 223 are operated by means of the low-voltage direct voltage, of which analog measuring electronics 225, an integrated circuit 216 and a modulator 226 are shown here. Measurement signals from various sensors of the cooking utensil 201 are sensed and digitized by means of the analog measurement electronics 225 . For the sake of simplicity, only three temperature sensors 227 attached to the underside of the pot base 220 are shown here, but other sensors can also be connected to the analog measurement electronics 225, e.g. B. pressure sensors or humidity sensors. Furthermore, an inherent temperature sensor 217 is present directly at a measurement input of the analog measurement electronics 225 . This thus measures the temperature in the area of this measurement input of the analog measurement electronics 225; since the pot electronics 223 are accommodated in a comparatively compact manner on a shared circuit board (not illustrated), the temperature at this measurement input is also considered to be representative of the temperature at the integrated circuit 216.

The analog measuring electronics 225 is connected on the output side to an input side of the integrated circuit 216, so that temperature data are forwarded from the analog measuring electronics 225 to the integrated circuit 216 for subsequent processing. The integrated circuit 216 has an A/D converter (not shown) for processing the analog temperature data transmitted by the measurement electronics 225 . In the integrated circuit 216, the digital "raw data" supplied by the analog measurement electronics 225 are reformatted into a format compatible for communication with the operating device 206. In particular, raw data is converted into a predetermined data format and log format. The formatted measurement data is then sent by the integrated circuit 216 cyclically, e.g. B. every 10 ms, forwarded to the modulator 226, where they are modulated onto a carrier signal to then be transmitted from the modulator 226 via an antenna 228 to the operating device 206. The antenna 228 is designed here as a signal winding running parallel to the bottom 220 of the pot. However, other measurement data can also be processed by the integrated circuit 216 and forwarded to the modulator 226, such as a measurement signal of a power voltage on the secondary side. In addition, other data can also be processed by the integrated circuit 216 and forwarded to the modulator 226, such as identification data (Identcode, etc.) and device status data, specifically cyclically or—in the case of bidirectional communication—on request. The operating device 206 has a receiving antenna 229 which is also designed as a signal winding which is essentially opposite the signal winding of the transmitting antenna 228 of the cooking utensil 201 . The receiving antenna 229 receives the modulated carrier signal emitted by the transmitting antenna 228 and forwards it to a demodulator 230, in which the data modulated onto the carrier signal is extracted and output again as readable digital data. Thus, both the data sensed by the analog measurement electronics 225 and the identification data or device status data supplied by the integrated circuit 216 are now present in the operating device. This data is further processed in a control unit ("stove electronics") 210 and evaluated for the operation of the cooking utensil 201 .

The temperature data sent by the cooking utensil 201, including the intrinsic temperature measurement data, can be present in the form of resistance values of the temperature sensors used if they are designed as resistance temperature sensors. From this, the actual temperature on the underside of the pot base 220 can be determined in the control unit 210 by looking up corresponding resistance/temperature characteristics in a look-up table and the temperature of the food to be cooked can be derived therefrom. For example, the temperature on the underside of the pot base 220 can be equated with the temperature of the food to be cooked, or an empirically determined temperature difference can be added, which can also depend on the level of the measured temperature. The control unit 210 also receives inputs from a control panel 204, for example via a target cooking product temperature for temperature regulation. For this purpose, an operator has previously set the target cooking product temperature on the control panel 204 directly or via a cooking program. Other controlled variables such as PID coefficients can also be sent to the control unit from the control panel 204 - unnoticed by the operator. In the case of temperature regulation, a control deviation between the setpoint cooking product temperature and the actual cooking product temperature can be determined in the control unit 210, as well as a manipulated variable of the control loop, from which a control voltage for controlling a power generation unit 212 in the form of power electronics is calculated and output. The control voltage is in a range between 0 V (switched off) and 4 V (maximum). For this purpose, a digital/analog converter 231 is inserted between the control unit 210 and the power generation unit 212 . An excitation field generating means 211 in the form of a spiral power winding is operated by means of the power generation unit 212, as already with reference to FIG figure 1 has been executed. For this purpose, the power generation unit 212 generates an alternating power voltage applied to the excitation field generation means 211, here for example between 10 VAC and 230 VAC at a frequency between 400 KHz and 100 KHz. The excitation field generating means 211 generates an alternating magnetic field as the excitation field, which in turn is picked up by the energy absorber 214 . In other words, an energy transfer based on induction results between the excitation field generating means 211 and the energy absorber 214 .

The control unit 210 also compares the transmitted value of the intrinsic temperature with at least one intrinsic temperature threshold value, as already described in more detail above. Depending on whether one of the intrinsic temperature thresholds has been reached or exceeded and, if applicable, which of several intrinsic temperature thresholds has been reached or exceeded, a warning can be issued or the excitation field generated by excitation field generation means 211 can be specifically weakened by reducing a control voltage for power generation unit 212 and In extreme cases it can even be switched off.

If the cooking utensil 201 is placed on the operating device 206, for example on the in figure 1 Worktop 105 shown, energy can be transmitted from the operating device 206 to the cooking utensil 201 and data signals can be transmitted from the cooking utensil 201 to the operating device 206. Due to the transformer or inductive coupling between Excitation field generating means 211 and energy absorber 214, however, energy transmission is only possible in a field close to the excitation field generating means 211 for operating the cooking utensil 201. Typical maximum distances between operating device 206 and cookware 201 are 3 to 10 cm. If the cooking utensil 201 is further removed from the excitation field generating means 211, the transmitted power is no longer sufficient to operate the cooking utensil 201. Then the transmitted energy is no longer sufficient to operate the pot electronics, which then stop working.

When the cooking utensil 201 approaches an operating device 206, it can re-enter the near field of the excitation field generating means 211 and thus be supplied with energy again. In this case, the top electronics 223 again emit signals which are recognized by the operating device 206 .

Of course, the present invention is not limited to the embodiment shown.

There can also be bidirectional communication between the cookware and the operating device. A device that can be operated by the operating device is not limited to cooking utensils, but can include any other food preparation device that can be operated electrically, such as a small household appliance. Reference List 101 cookware 222 heating track 102 body 223 pot electronics 104 control panel 224 switching regulator 105 countertop 225 analog measurement electronics 106 control gear 226 modulator 107 power transmission unit 227 temperature sensor 108 Housing 228 transmitting antenna 109 actuator 229 receiving antenna 110 control unit 230 demodulator 111 excitation field generating means 231 D/A converter 112 power generation unit 113 energy transfer area 114 energy absorber 115 line 116 integrated circuit 117 intrinsic temperature sensor 201 cookware 202 body 206 control gear 210 control unit 211 excitation field generating means 212 power generation unit 214 energy absorber 216 integrated circuit 217 intrinsic temperature sensor 220 pot bottom 221 food

Claims (14)

1. Food preparation attachment device (101; 201), having

   - at least one transmitter (226; 228) for transmitting data to an external unit (106; 206),

   - at least one integrated circuit (116; 216) for processing data and for outputting data to the transmitter (226; 228) based on the processing,

   - at least one energy absorber (114; 214) in the form of a coil for the transformer absorption of energy from an electromagnetic excitation field for the power supply of the integrated circuit (116; 216) and the transmitter (226; 228) and

   - a heating element,

   characterised in that

   - the heating element can be supplied with energy for its operation by means of the at least one energy absorber (114; 214),

   - the food preparation attachment device (101; 201) has an intrinsic temperature determination unit (117; 217) for determining an intrinsic temperature of the integrated circuit (116; 216) and

   - the integrated circuit (116; 216) is designed for processing intrinsic temperature data determined by the intrinsic temperature determination unit (117; 217) and for outputting the intrinsic temperature data to the transmitter (226; 228) based on the processing of the intrinsic temperature data.
2. Food preparation attachment device (101; 201) according to claim 1, in which the transmitter (226; 228) is at least partially integrated into the integrated circuit (116; 216).
3. Food preparation attachment device (101; 201) according to claim 1 or 2, in which the transmitter (226; 228) has a modulator (226) and an antenna (228) connected downstream of the modulator (226), in particular with at least one signal winding.
4. Food preparation attachment device according to one of the preceding claims, in which the transmitter is a transceiver.
5. Food preparation attachment device (101; 201) according to one of the preceding claims, in which at least partially analogue measuring electronics (225) are integrated into the integrated circuit (216).
6. Food preparation attachment device (101; 201) according to one of the preceding claims, further having at least one sensor unit (217; 227) for sensing at least one physical measured variable, wherein the at least one integrated circuit (216) is designed for processing sensor data of the at least one sensor unit (217; 227) and for outputting data to the transmitter (226; 228) based on this processing.
7. Food preparation attachment device (101; 201) according to one of the preceding claims, which is designed as cookware.
8. Food preparation attachment device (101; 201) according to claim 7, wherein the integrated circuit (116; 216) and the transmitter (226; 228) are arranged underneath a saucepan bottom (220) of a food preparation device (101; 201) embodied as a saucepan.
9. Food preparation attachment device (101; 201) according to claim 8, wherein the heating element is embodied as a heating track (222) running on an underside of a saucepan bottom (220) and upon application of current is heated and then heats up the saucepan bottom (220).
10. Food preparation attachment device (101; 201) according to one of the preceding claims, in which a power output of not more than 10 watts is provided for data communication, specifically not more than 5 watts, in particular not more than 3 watts.
11. Food preparation attachment device (101; 201) according to one of the preceding claims, in which the intrinsic temperature determination unit (117; 217) has an intrinsic temperature sensor (117; 217) connected to or integrated in the integrated circuit (116; 216).
12. Operating device (106; 206) for operating a food preparation attachment device (101; 201) according to one of the preceding claims, having at least one excitation field generating means (111; 211), in particular a coil, for generating the electromagnetic excitation field, characterised in that the operating device (106; 206) has a receiver (229; 230) for receiving data which has been transmitted by the transmitter (226; 228) of the food preparation attachment device (101; 201), as well as a control unit (110; 210) for setting a strength of the electromagnetic excitation field on the basis of the received data, wherein the control unit (110; 210) is designed to carry out a comparison of the intrinsic temperature with at least one intrinsic temperature threshold value upon receipt of intrinsic temperature data.
13. Operating device (106; 206) according to claim 12, which, when the intrinsic temperature reaches or exceeds an intrinsic temperature threshold value, outputs a warning signal and/or reduces a strength of the electromagnetic excitation field.
14. Operating device (106; 206) according to claim 13, which reduces a strength of the electromagnetic excitation field as a function of a level of one of a plurality of intrinsic temperature threshold values.

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