Method and device for operating a hob, cookware and hob

Description

[0001] The invention relates to a method for operating a hob, as well as to a cookware and a system comprising a cookware and a hob.

[0002] Induction-compatible cookware can have a heat-insulating base to allow it to be used in conjunction with a cooktop featuring a cooking surface made of a material with lower temperature resistance and thermal shock resistance than glass ceramic. Lower temperature resistance compared to glass ceramic means that the material will discolor or experience other damage such as deformation, blistering, cracking, etc. at temperatures above 250°C. The term temperature resistance also includes thermal shock resistance. Glass ceramics, on the other hand, can withstand temperatures of over 500°C.

[0003] DE 10 2006 014 818 A1 describes such a cookware with a heat-insulating base. EP2 757 660 A1 describes a method for operating a hob according to the preamble of claim 1.

[0004] From the publications CH 711 124 A2 and DE 10 2008 054 911 A1, as well as JP 2007134257 A, it is known to arrange a temperature sensor for detecting the temperature of the food being cooked in the cookware. The temperature of the food being cooked can be used as a control variable for the power provided by the hob in an automated or monitored cooking process. The publication EP 3 225 918 A1 shows a table with a sensor for detecting the temperature of the food being cooked in the cookware.

[0005] The invention has for its object to provide an improved method for operating a hob, an improved device for operating a hob, as well as an improved cookware and an improved hob.

[0006] According to the invention, this object is achieved by a method for operating a hob, as well as a cookware and a system comprising a cookware and a hob according to the main claims. Advantageous embodiments and further developments of the invention emerge from the following subclaims.

[0007] The advantages achievable with the invention are that the installation temperature of a cookware item can be detected in order to control a function of a cooktop depending on the installation temperature. This is advantageous for limiting the temperature at the bottom of the cookware when the cooking surface of the cooktop is not made of a material with high thermal shock resistance, such as glass ceramic, but rather of wood or natural stone, for example. Advantageously, a variety of materials can be used for the cooking surface of the cooktop.

[0008] Although the approach described is based on a household appliance, the approach described here can be used accordingly in the context of a commercial or professional appliance.

[0009] A method for operating a cooktop is presented. The method comprises a reading step and a providing step. In the reading step, a temperature signal representing a current set-up temperature of a piece of cookware is read. In the providing step, a control signal is provided that is designed to control a function of the cooktop. The control signal is provided using a comparison of the set-up temperature represented by the temperature signal with a reference value.

[0010] The hob can be an induction hob, for example. A cooking surface of the hob can be formed from natural stone or wood, for example. The cookware can be a cooking container such as a pot or pan that is suitable for use on such a hob. For this purpose, the cookware can have, for example, an insulating outer wall or an insulating shell. Additionally or alternatively, the cookware can have an intrinsic temperature limit or a temperature monitoring mechanism, for example an overtemperature switch. The temperature signal can represent a sensed temperature value and additionally or alternatively a voltage of a temperature-sensitive element. The installation temperature of the cookware can be detected on a heat-insulating element such as the outer wall of the cookware.The control signal can be designed to adjust the power of the hob, for example, to reduce the power. The reference value can be, for example, a maximum temperature value, which can be set depending on the temperature resistance of the cooking surface, for example. The method presented here can be carried out using appropriately designed cookware. Additionally or alternatively, the method can be carried out using an appropriately designed hob. Furthermore, the method can also be carried out on a system comprising a hob and cookware. Embodiments of the appropriately designed cookware and hob are described in more detail below.

[0011] According to one embodiment, a cooking temperature signal can additionally be read in during the reading step. The cooking temperature signal can represent a temperature of the contents of the cookware. In the providing step, the control signal can be provided using the cooking temperature signal. This is advantageous for monitoring a cooking process in the cookware and thus on the hob.

[0012] In addition, according to one embodiment, a recognition signal can be read in during the reading step. The recognition signal can represent a type of cookware. In the providing step, the control signal can be provided using the recognition signal. In addition to the type of cookware, a size of the cookware can also be recognized in order to control the function of the hob depending on the type and size of the cookware. Recognizing the type of cookware is advantageous in order to ensure that cookware suitable for the hob is used. The cookware can be recognized, for example, as cookware with a cold wall, i.e., as cookware with an outer wall that is colder than an inner wall of the cookware when the cookware is in operation. This advantageously prevents damage to the hob due to the use of unsuitable cookware.

[0013] Alternatively or additionally, a unique ID for the cookware can also be recognized. This makes it possible to distinguish between cookware of the same type and size.

[0014] In the providing step, the control signal can be designed, according to one embodiment, to control switching on the hob and, additionally or alternatively, switching off the hob. Additionally or alternatively, the control signal can be designed to control setting a power level of the hob. Furthermore, the control signal can also be designed to control output of a warning signal. If the installation temperature is above the reference value, for example, the control signal can be designed to switch off the hob or reduce the power level of the hob. The warning signal can be output, for example, as an acoustic or visual signal from the hob. Additionally or alternatively, the warning signal can also be output using a warning device of the cookware.

[0015] According to one embodiment, the method can further comprise a step of sensing the current set-up temperature of the cookware. The result of the sensing can be provided as the temperature signal. For this purpose, the cookware and additionally or alternatively the hob can comprise, for example, a temperature measuring device designed to detect the temperature signal. To detect the set-up temperature, a sensor element, for example a temperature sensor, can be arranged on the heat-insulating outer wall of the cookware. Advantageously, the set-up temperature can be detected quickly and reliably in this way. Furthermore, the set-up temperature can also be monitored in this way over a period of time, for example during operation of the hob.

[0016] A device for operating a cooktop is also presented. The device comprises a reading device and a providing device. The reading device is designed to read a temperature signal representing a current set-up temperature of a piece of cookware. The providing device is designed to provide a control signal for controlling a function of the cooktop. The control signal is provided using a comparison of the set-up temperature represented by the temperature signal with a reference value.

[0017] The device presented here can also be configured to perform, control, or implement the steps of a variant of the method presented here in corresponding devices. This embodiment of the invention in the form of a device also allows the problem underlying the invention to be solved quickly and efficiently.

[0018] The device can be designed to read in input signals and to determine and provide output signals using the input signals. An input signal can, for example, represent a sensor signal that can be read in via an input interface of the device. An output signal can represent a control signal or a data signal that can be provided at an output interface of the device. The device can be designed to determine the output signals using a processing rule implemented in hardware or software. For example, the device can comprise a logic circuit, an integrated circuit, or a software module and can, for example, be implemented as a discrete component or be comprised of a discrete component.

[0019] Also advantageous is a computer program product or computer program with program code that can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory, or an optical memory. If the program product or program is executed on a computer or device, the program product or program can be used to carry out, implement, and / or control the steps of the method according to one of the embodiments described above.

[0020] This approach also presents a cookware item. The cookware comprises an embodiment of the aforementioned device for operating a hob. In this way, when the cookware is used in conjunction with a hob with a cooking surface made of a material with limited thermal shock resistance, such as wood or natural stone, it is advantageously possible to maintain a specific bottom temperature of the cookware.

[0021] The cookware has an outer wall designed to be thermally insulated. The cookware has an inner wall designed to be heated by electromagnetic induction.

[0022] The cookware can, for example, have a heat-insulating base as the outer wall. The cookware can also be formed in two parts, for example, with a stainless steel inner container that can be inserted into a heat-insulating cover.

[0023] In addition, according to one embodiment, the cookware can also comprise an induction coil. The induction coil can, for example, be arranged as a heating element in a space between an outer wall and an inner wall on the bottom of the cookware. If the reference value of the temperature signal is reached or exceeded, the coil can, for example, be short-circuited or disconnected. In this case, the control signal can, for example, represent a change in impedance. Additionally or alternatively, the cookware can comprise a temperature measuring device. The temperature measuring device can, for example, comprise a sensor element designed to detect the set-up temperature of the cookware. Optionally, the temperature measuring device can also be designed to detect a temperature in or on the cooking container of the cookware in order to monitor a cooking process.The cookware may additionally or alternatively also comprise a communications interface. The communications interface may be designed for the wireless transmission of an electrical signal. Additionally or alternatively, the communications interface may be designed for the transmission of an acoustic and / or visual signal. The communications interface may also be designed to connect the cookware to the hob in a signal-transmitting manner. The control signal may, for example, be provided from the cookware to the hob via the communications interface. If the control signal is designed to trigger the warning signal, it may, for example, be transmitted as an acoustic signal. Alternatively, the cookware may also comprise a sound generating device and, additionally or alternatively, a display element.In this case, if the reference value is reached or exceeded, the cookware can be designed to emit an acoustic and / or visual warning to warn a user of the cookware.

[0024] A cooktop is also presented using this approach. The cooktop comprises an embodiment of the aforementioned device for operating the cooktop. The cooktop can be used, for example, in conjunction with an embodiment of the described cookware.

[0025] According to one embodiment, the cooktop can further comprise a cooktop communication interface for wirelessly transmitting an electrical and / or acoustic and / or visual signal. The cooktop communication interface can be similar to or equivalent to the communication interface of the cookware described above. Furthermore, the communication interface can be configured to connect the cooktop to the cookware in a signal-transmitting manner.

[0026] Embodiments of the invention are shown purely schematically in the drawings and are described in more detail below. Figure 1 shows a schematic representation of a device for operating a hob according to an embodiment; Figure 2 shows a schematic representation of a piece of cookware and a hob with a device for operating the hob according to an embodiment; Figure 3 shows a schematic representation of a piece of cookware with a device for operating a hob according to an embodiment; Figure 4 shows a schematic representation of a piece of cookware according to an embodiment; Figure 5 shows a schematic representation of a piece of cookware according to an embodiment; Figure 6 shows a schematic representation of a piece of cookware according to an embodiment; Figure 7 shows a flowchart of a method for operating a hob according to an embodiment.

[0027] In the following description of advantageous embodiments of the present approach, the same or similar reference numerals are used for the elements shown in the various figures and having a similar effect, whereby a repeated description of these elements is omitted.

[0028] Figure 1shows a schematic representation of a device 100 for operating a cooktop according to an exemplary embodiment. The device 100 comprises a reading device 105 and a providing device 110. The reading device 105 is designed to read in a temperature signal 115. The temperature signal 115 represents a current set-up temperature of a cooking utensil 120. The providing device 110 is designed to provide a control signal 125 for controlling a function of the cooktop. The control signal 125 is provided using a comparison of the set-up temperature represented by the temperature signal 115 with a reference value.

[0029] The temperature signal is provided here, for example, by the cookware 120. The device 100 shown here can be arranged in the cookware 120 or in the hob. The control signal 125 is optionally provided to the hob or to the cookware 120.

[0030] According to one embodiment, the reading device 105 is additionally configured to read in a cooking temperature signal 130. The cooking temperature signal 130 represents a temperature of a content of the cookware 120. In this case, the providing device 110 is configured to provide the control signal 125 using the cooking temperature signal 130.

[0031] Furthermore, according to one embodiment, the reading device 105 is configured to read in a recognition signal 135. The recognition signal 135 represents a type of cookware 120. The providing device 110 is then configured to provide the control signal 125 using the recognition signal 135.

[0032] According to one embodiment, the control signal 125 is configured to control, as a function of the hob, switching on and additionally or alternatively switching off the hob. Furthermore, the control signal 125 is configured to control setting a power level of the hob and additionally or alternatively outputting a warning signal.

[0033] This is advantageous when alternative surfaces to glass ceramic, such as wood or natural stone, are used for the cooktop. Monitoring the bottom temperature of the cookware 120 and limiting the temperature are required, which can be implemented using the device 100 shown here. This prevents excessively high temperatures and / or large temperature gradients occurring during induction cooking, coupled with the thermal conductivity of the material, from causing tension in the cooktop material, which could potentially damage the material. Reading the detection signal 135 is advantageous in identifying the cookware 120 suitable for such a cooktop. Only after successful identification is the power of the cooktop controlled by means of the control signal 125.The cookware 120 is recognized, for example, using a unique identifier transmitted by radio or by identifying an operating feature of the cookware 120. To recognize the type of cookware 120, it is detected, for example, whether the cookware 120 has insulation, an intrinsic temperature limitation, or a temperature monitoring feature.

[0034] Figure 2 shows a schematic representation of a cooking utensil 120 and a cooking hob 205 with a device 100 for operating the cooking hob 205 according to an embodiment. The cooking hob 205 has a cooking surface 210 and comprises the device 100, which is similar to the one shown in FIG. Fig. 1 The device described is similar to or corresponds to the one described. A cooking pot is shown as an example of cooking utensil 120. The cooking surface 210 can be formed from wood or natural stone, for example.

[0035] According to the exemplary embodiment shown here, the cookware 120 has an outer wall 215 designed to provide thermal insulation. Accordingly, this layer of the cookware 120, the outer wall 215, is also referred to as a thermal insulator or "cold outer wall insulation." For thermal insulation, the outer wall 215 comprises, for example, a thermal insulation material, or the Curie temperature of the outer wall 215 is reduced. The cookware 120 also has an inner wall 220 designed to be heated by means of electromagnetic induction. The cookware 120 here, for example, has a cooking container with the inner wall 220 and a thermal insulator with the outer wall 215. The cooking container is accordingly formed from an active material for induction. The cookware 120 can also be designed in two parts: In this case, the outer wall 215 is shaped as a heat-insulating shell, and the cooking container is shaped so that it can be removed from the shell.

[0036] According to the exemplary embodiment shown here, the cookware 120 also comprises a temperature measuring device 225 and a communication interface 230 for wirelessly transmitting an electrical and / or acoustic and / or visual signal. The temperature measuring device 225 has, for example, four sensor elements embodied as thermocouples: A first temperature sensor 240 is arranged on a support surface, i.e., the bottom of the cookware 120. The first temperature sensor 240 is accordingly referred to as the "insulation - support surface temperature sensor." The first temperature sensor 240 is designed to detect the current support temperature of the cookware 120 in order to provide the temperature signal. A second temperature sensor 241 is arranged on an outer side of the inner wall 220 toward the support surface of the cookware 120 and is also referred to as the "pot bottom temperature sensor."A third temperature sensor 242 and a fourth temperature sensor 243 are also arranged on a lateral section of the inner wall. The third temperature sensor 242 and the fourth temperature sensor 243 are also referred to as "pot wall temperature sensors." Temperatures in or on the inner wall 220, and thus in or on the cooking container of the cookware 120, are detected by the second temperature sensor 241, the third temperature sensor 242, and the fourth temperature sensor 243. The measured temperature is then transmitted, together with the other temperatures related to the cooking process, to the cooktop 205 via the communication interface 230 and evaluated to provide the control signal.

[0037] The hob 205 is designed to execute a function of the hob 205 in response to the control signal, for example to reduce the power, to switch off the hob 205, or to emit a warning signal.

[0038] In addition, according to one embodiment, the cooktop 205 may include a cooktop communication interface that is similar or equivalent to the communication interface 230 shown here.

[0039] Figure 3 shows a schematic representation of a cookware item 120 with a device 100 for operating a cooktop according to an exemplary embodiment. In the exemplary embodiment shown here, the cookware item 120 comprises the device 100, which is arranged, for example, between the inner wall 220 and the outer wall 215. The cookware item also comprises the communication interface 130 and the second, third, and fourth temperature sensors 241, 242, 243.

[0040] Furthermore, the cookware according to the exemplary embodiment shown here comprises an overtemperature switch 305, which is arranged instead of the first temperature sensor on an inner side of the outer wall 215 in the direction of the installation surface of the cookware 120. The overtemperature switch 305 can be designed as a bimetallic switch and is designed to switch when the reference value of the installation temperature is reached or exceeded. In this case, the temperature signal represents a discrete value, i.e., 0 or 1. The overtemperature switch 305 and the temperature sensors 241, 242, 243 are connected here, for example, to the communication interface 130. The communication interface is designed to transmit the control signal to the cooktop.

[0041] Figure 4shows a schematic representation of a cookware item 120 according to an exemplary embodiment. The cookware item 120 shown here is similar or corresponds to the cookware described with reference to previous figures. According to the exemplary embodiment shown here, the outer wall 215 is designed to be thermally insulated, and the inner wall 220 is designed to be heatable by means of electromagnetic induction. Furthermore, the cookware item 120 has the temperature measuring device with the first temperature sensor 241, the second temperature sensor 242, and the third temperature sensor 243, as well as the communication interface 230 and the overtemperature switch 305.

[0042] According to the exemplary embodiment shown here, the cookware 120 also comprises an induction coil 405. The induction coil 405 is designed here to supply the communication interface 230 with voltage, which is energy-saving and can also be referred to as energy harvesting. Furthermore, the overtemperature switch 305 is connected to the induction coil 405 and designed to interrupt the voltage supply between the induction coil 405 and the communication interface 230 when the reference value of the installation temperature is reached or exceeded, in order to control the cooktop to switch off or reduce its power. The control of the cooktop function occurs in response to a lack of communication between the communication interface 230 and the cooktop.

[0043] Figure 5shows a schematic representation of a cooking utensil 120 according to an exemplary embodiment. The cooking utensil 120 shown here is similar to or corresponds to the cooking utensil described with reference to previous figures and here comprises the overtemperature switch 305 and the induction coil 405. As a communication interface, the cooking utensil 120 here comprises, for example, an acoustic module 505 for sound generation, which may, for example, comprise a loudspeaker. Additionally or alternatively, the cooking utensil can also comprise a visual module, which may, for example, have a light-emitting diode. According to the exemplary embodiment shown here, the overtemperature switch 305 is connected to the acoustic module 505 and is designed to switch the voltage applied to the acoustic module 505 when the reference value of the setup temperature is reached or exceeded in order to trigger the output of a warning signal.For this purpose, the overtemperature switch 305 is connected to a coil such as the induction coil 405 shown here. The acoustic module 505 is arranged, for example, in the outer wall of the cookware 120 and can also be referred to as a warning signal generator. The output of an acoustic warning signal by means of the acoustic module 505 and additionally or alternatively a visual warning signal by means of the visual module can be designed to indicate to a user of the cookware 120 or the cooktop that the cooktop has been switched off or reduced in power.

[0044] Figure 6shows a schematic representation of a cookware item 120 according to an exemplary embodiment. The cookware item 120 shown here is similar to or corresponds to the cookware described with reference to previous figures and comprises the excess temperature switch 305 and the induction coil 405, which are connected to one another and are arranged, for example, in the region of the pot base between the inner wall and the outer wall of the cookware item 120. The excess temperature switch 305 is designed to short-circuit the induction coil 405 or to disconnect the connection to the induction coil 405 when the reference value of the setup temperature is reached or exceeded. This influences a coupling between the induction coil 405 shown here and another coil, which is arranged, for example, in the cooktop, whereby an impedance change occurs that can be detected by the cooktop.In this case, the control signal is designed to control the function of the hob in response to the impedance change in order to switch the hob off or reduce the power of the hob.

[0045] Figure 7 shows a flowchart of a method 700 for operating a cooktop according to an exemplary embodiment. The method 700 shown here can be executed in conjunction with the device described above. The method 700 comprises a reading step 705 and a providing step 710. In reading step 705, a temperature signal representing a current set-up temperature of a piece of cookware is read in. In providing step 710, a control signal designed to control a function of the cooktop is provided. The control signal is provided using a comparison of the set-up temperature represented by the temperature signal with a reference value.

[0046] According to one embodiment, method 700 further includes a step 715 of sensing the current set-up temperature of the cookware. The result of the sensing is provided as the temperature signal. Sensing step 715 is optionally performed before reading step 705.

[0047] If an embodiment includes an "and / or" link between a first feature and a second feature, this should be read as meaning that the embodiment according to one embodiment has both the first feature and the second feature and according to another embodiment has either only the first feature or only the second feature.

Claims

1. Method (700) for operating a hob (205), the method (700) comprising the following steps: reading (705) a cooking temperature signal (130) which represents a temperature of a content of the cooking utensil (120); and providing (710) a control signal (125) which is designed to control a function of the hob (205), the control signal (125) being provided using the cooking temperature signal (130), characterised in that in the reading step (705), a temperature signal (115) from a temperature sensor (240) of the cooking utensil (120) is additionally read, which signal represents a current placement temperature of a cooking utensil (120); and in the providing step (710), the control signal (125) is provided by comparing the placement temperature represented by the temperature signal (115) with a reference value.

2. Method (700) according to any of the preceding claims, wherein, in the reading step (705), a recognition signal (135) is read, which represents a type of cooking utensil (120), wherein, in the providing step (710), the control signal (125) is provided using the recognition signal (135).

3. Method (700) according to either of the preceding claims, wherein, in the providing step (710), the control signal (125) is designed to control switching on of the hob (205) and / or switching off of the hob (205) and / or an adjustment of a power of the hob (205) and / or an output of a warning signal as a function of the hob (205).

4. Method (700) according to either of claims 1 or 2, comprising a step (715) of sensing the current placement temperature of the cooking utensil (120), wherein the result of the sensing is provided as the temperature signal (115).

5. Cooking utensil (120) having a temperature measuring device (225) and an apparatus (100), the apparatus (100) comprising a reading device (105) which is designed to read a temperature signal (115), and the apparatus (100) comprising a providing device (110) which is designed to provide a control signal (120) for controlling a function of the hob (205), characterised in that the temperature signal (115) represents a current placement temperature of a cooking utensil (120), and the control signal (125) is provided by comparing the placement temperature represented by the temperature signal (115) with a reference value, the cooking utensil (120) has an outer wall (215) which is designed to thermally insulate, and with an inner wall (220) which is designed to be heatable by means of electromagnetic induction, and the temperature measuring device (225) has a temperature sensor (240) which is arranged on the thermally insulating outer wall (215) of the cooking utensil (120).

6. System comprising a hob (205) and a cooking utensil (120) which has an apparatus (100), comprising the following features: the apparatus (100) comprising a reading device (105) which is designed to read a temperature signal (115), and the apparatus (100) comprising a providing device (110) which is designed to provide a control signal (120) for controlling a function of the hob (205), characterised in that the temperature signal (115) represents a current placement temperature of a cooking utensil (120), and the control signal (125) is provided by comparing the placement temperature represented by the temperature signal (115) with a reference value, and in that the cooking utensil (120) has an outer wall (215) which is designed to thermally insulate, and with an inner wall (220) which is designed to be heatable by means of electromagnetic induction, and in that the temperature measuring device (225) has a temperature sensor (240) which is arranged on the heat-insulating outer wall (215) of the cooking utensil (120).

7. Cooking utensil (120) according to the preceding claim 5, wherein a second temperature sensor (241) is arranged on an outer side of the inner wall (220).

8. Cooking utensil (120) according to any of the preceding claims or 7, wherein the cooking utensil (120) is formed in two parts and has an inner container made of stainless steel, which can be inserted into a heat-insulating casing.

9. Cooking utensil (120) or system according to any of the preceding claims 5, 7 or 8, wherein the method according to any of claims 1 to 4 is carried out by means of the apparatus (100).

10. Cooking utensil (120) according to any of the preceding claims 5 or 7 to 9, having an induction coil (405) and / or having a communication interface (230) for wirelessly transmitting an electrical and / or acoustic and / or visual signal.

11. Cooking utensil (120) according to any of the preceding claims 5 or 7 to 10, wherein the induction coil (405) is arranged in a space between the outer wall (215) and the inner wall (220) at the bottom of the cooking utensil (120).

12. Cooking utensil (120) according to any of the preceding claims 5 or 7 to 11, wherein the induction coil (405) is short-circuited or disconnected when the reference value of the temperature signal (115) is reached or exceeded.

13. System according to the preceding claim 6, wherein the hob (205) has a cooking surface (210) made of a material which has a limited thermal shock resistance compared to glass ceramics, for example the cooking surface (210) is formed from wood or a natural stone.

14. System according to any of the preceding claims or 13, wherein the hob (205) has a hob communication interface for wirelessly transmitting an electrical and / or acoustic and / or visual signal.