WO2015018886A1

WO2015018886A1 - Cooking device and method for operating a cooking device

Info

Publication number: WO2015018886A1
Application number: PCT/EP2014/066978
Authority: WO
Inventors: Volker Backherms; Eduard Sailer; Holger Ernst; Sonja Schöning
Original assignee: Miele & Cie Kg
Priority date: 2013-08-09
Filing date: 2014-08-07
Publication date: 2015-02-12
Also published as: EP3031298A1; DE102013108646A1

Abstract

The cooking device comprises a cooking hob with a cooking point and a heating device for heating a cooking area. A sensor device for detecting a characteristic variable which directly depends on temperatures of the cooking area and a control device are provided. The control device is designed and is suitable for controlling the heating device as a function of the variable detected by the sensor device. A sensor module for detecting a variable which indirectly depends on temperatures of the cooking area is associated with the sensor device.

Description

description

"Cooking device and method for operating a cooking device"

The present invention relates to a cooking device and a method of operating such. The cooking device is used in particular for the preparation of food. The

Cooking device comprises at least one hob with at least one cooking point and at least one heating device provided for heating at least one cooking area.

In the prior art cooking appliances have become known that offer automatic functions. A prerequisite for such an automatic operation of a cooking device is sometimes a detection of various parameters that are characteristic of the cooking process, such. B. the temperature of the food container and in particular the pot bottom. Depending on the detected parameters then the automatic function and in particular the heating power of the cooking device are controlled. The heat source must be controlled so that z. B. an undesirable overheating of the food is avoided. Therefore, the reliability or accuracy of the detected parameters is crucial to the functionality of the automatic function.

In the prior art, for example, devices have become known for determining temperatures during cooking and cooking processes, which determine the temperature on the underside of a food container without contact. This is how z. B. the WO 2008/148 529 A1 a heat sensor below a hob plate before, which detects the radiated heat radiation and determines the temperature of the Gargutbehälters or the pot bottom.

The known devices and methods are suitable for use

Automatic functions of cooking appliances, such. As a stove, but still capable of improvement. For example, an automatic boil-up of milk without overcooking the milk places very high demands on the corresponding devices and methods with regard to the reproducibility and the accuracy. Furthermore, should for the

Automatic function reliably detected certain phases of a cooking or cooking process, for example, when a aufkochende food begins to boil.

It is therefore the object of the present invention to provide a cooking device and a method which allow reliable monitoring of a cooking process.

This object is achieved by a cooking device with the features of claim 1 and by a cooking device with the features of claim 10 and a method having the features of claim 11. Preferred features are the subject of the dependent claims. Further advantages and features will become apparent from the general description of the invention and the description of the embodiments.

The cooking device according to the invention comprises at least one hob with at least one cooking point and at least one heating device for heating at least one

Cooking area. At least one sensor device is provided for detecting at least one characteristic variable directly dependent on temperatures of the cooking region and at least one control device. The control device is designed and suitable for controlling the heating device as a function of the at least one variable detected by the sensor device. In this case, the sensor device is associated with at least one sensor module for detecting at least one size indirectly dependent on temperatures of the cooking area.

The cooking device according to the invention has many advantages. A significant advantage is that at least one sensor module is provided for detecting at least one size dependent indirectly on temperatures of the cooking area. The sensor module allows at least partially redundant determination of temperature conditions of the cooking area, which cooking processes can be monitored very reliable.

A reliable and reproducible capture of sizes directly with the

Temperature correlate, z. B. with the in the unpublished font

DE 10 2013 10 21 19.0 described cooking device possible. There, temperatures of the cooking area are determined by means of thermal radiation, wherein the detected heat radiation depends directly on the temperatures in the cooking area. However, it is advantageous to record further parameters in the monitoring of cooking processes necessary for automatic functions. The present invention therefore detects at least one variable dependent on the temperature and thus has the advantage that an even better monitoring of cooking processes is possible.

For example, it can be determined so reliably whether a food boils or not. The indirect size, d. H. the indirectly dependent on temperatures of the cooking area size, it can be z. B. characteristic of a boiling noise. The sensor device also detects a directly dependent on temperatures of the cooking area size, z. B. via a heat sensor. Although this direct size can usually be reliable

Conclusion on the temperature to be taken in the cooking area, however, is the

Cooking state of a food, so whether it is boiling, for example, but usually not alone based on the temperature reliably determined because z. B. the boiling point of

Water content and the surrounding air pressure is affected. By taking into account the indirect size, ie z. B. the Siedgeräusches, can now be closed much more reliable on the cooking state. The sensor module assigned to the sensor module may be a separate sensor module. But it is also possible at least partially integrated into the sensor device

Sensor module. It is possible that the sensor module is part of an electronic circuit, wherein the part of the electronic circuit is adapted to output a parameter suitable as an indirect variable. This is particularly advantageous because no additional sensor module is needed, but the indirect size in an electronic

Circuit, z. As a microcontroller, can be "tapped" at a suitable location.

The sensor module can also be any sensor of the heating device and / or a

Safety device and / or other device of the cooking device. The sensor module can be operatively connected to the sensor device. However, it can also not be in operative connection with the sensor device and, for example, be in operative connection with a control device, which in particular also with the sensor device in

Active compound is. The feature that the sensor module is assigned to the sensor device here means, in particular, a consideration of the values detected by the sensor module during a processing of the values detected by the sensor device. The assignment therefore does not have to be a physical assignment, but rather can be an assignment related to the processing of the detected quantities.

In particular, the variable detected by the sensor module does not correlate directly with the temperature and / or is preferably independent of it. For example, this is the case for a size describing a vibration in the cooking area or a voltage of a heating source. However, it is possible that the indirect size changes depending on a temperature or a temperature change. But regardless of such a dependency, no particular temperature value can be determined from the indirect variable. For example, the boiling noise of a liquid of unknown composition, such as. As a soup, although dependent on the temperature, since the temperature must correspond to the boiling point. However, since the boiling point of the liquid does not depend only on the temperature, it is not possible to directly determine the temperature of the liquid from the boiling noise. In contrast, from a directly dependent on the temperature size, z. As the value of the electrical resistance of a PT100 sensor, the temperature of an unknown fluid can be determined directly, even if the liquid to be measured is not known.

The cooking area can also include a food container placed there.

For example, the detected variables are then used to determine the temperature of the food container in the cooking area and in particular its underside and / or its contents. In particular, the control device is suitable and designed to control the heating device at least partially as a function of the size detected by the sensor module. This is particularly advantageous because the control of the heater below

Considering at least one indirect size particularly well to the respective

Cooking state can be adjusted. For example, the heating device by the controller to the boiling point with increased power and then with

be operated according to adapted power. Such an embodiment many reliable cooking functions are reliably possible, such. B. an automatically controlled cooking in hot water just below the boiling point (so-called simmering).

The control device, which is provided in particular for the registration and processing of the indirect and / or direct size, can be a central control device of the cooking device. It is also possible that the control device is assigned to certain devices of the cooking device, such. B. the sensor device or heater. It can also be several, shared or separately trained,

Be provided control devices.

It is preferred that the control device is suitable and designed to determine at least one characteristic temperature range of a cooking process on the basis of at least one variable detected by the sensor device and / or the sensor module. The characteristic temperature range is z. As the temperature range of a silent boiling, bubbling or film boiling of food such as water. It is also possible a boiling range of oil or fat or other food. Also the temperature range for a sharp searing or a cooking below the boiling point may be a characteristic temperature range of the cooking process. Any other are possible

Temperature ranges that characterize a cooking process.

It is also preferred that the control device is suitable and designed for this purpose

Dependence of a change of the detected indirectly dependent variable over time to recognize at least one characteristic temperature range of a cooking process. In particular, the control device is suitable and designed to detect a boiling plateau and / or a boiling point and / or temperature ranges outside and / or in the region of a boiling point. For example, vibrations and / or sounds can be detected and registered over time. On the basis of the change in vibration and / or noise over time can thus z. B. the transition from still boiling to Blasensieden be recognized.

Particularly preferably, the sensor module is suitable and designed to detect at least one electrical parameter of the heating device. Preferably, the electrical

Parameter is a quantity that is indirectly dependent on the temperatures of the cooking area. Of the electrical parameters is in particular an electrical power consumption and / or an electrical power output. The sensor module can at least one

Voltage sensor and / or comprise a current sensor and / or a resistance sensor or be designed as such. Also possible are other sensors for detecting electrical and / or magnetic parameters. In this case, the control device can be suitable and designed to compare the electrical parameter with the direct variable detected by the sensor device.

Preferably, the heating device comprises at least one induction device. The

Induction device is designed in particular as an induction heating source and comprises at least one induction coil. It is possible that the induction device comprises a plurality or a plurality of smaller induction coils. Then it is possible that the cooking area, for example, results flexibly by placing a Gargutbehälters. It is also possible that fixed hotplates are specified.

Such configured cooking device, wherein the sensor module has an electrical

Detected parameters of the induction device as an indirect variable, can be used particularly advantageous for detecting a temperature range of cooking operations.

For example, as parameters the voltages in different areas of the

Resonant circuit of the induction device are detected. It can be calculated in a conventional manner, the permeability of a Gargutbehälters in the cooking area, including in particular the control device is formed. Since the permeability of the Gargutbehälters usually decreases with increasing temperature, by changing the

Permeability over time to be closed to a change in temperature. The permeability is therefore in particular an indirectly dependent on temperatures of the cooking area size.

In particular, the sensor module comprises at least one vibration sensor and / or at least one acceleration sensor and / or at least one noise sensor and / or at least one voltage sensor and / or at least one current sensor and / or at least one magnetic field sensor. The sensor module may also comprise at least one piezoelectric sensor element and / or microphone and / or at least one

having electroacoustic transducer. The piezoelectric sensor element can

For example, output a pressure, an acceleration and / or a force as a corresponding voltage signal. Also possible are two or more identical and / or different sensors. In this case, two or more identical or different indirect variables can also be detected.

The hob can have at least one carrier device for positioning at least one food container. The carrier device may, for example, a glass ceramic plate or the like. In this case, the sensor module is preferably arranged in the installed position of the hob at least partially below the support means. In particular the

Vibration sensor or the noise sensor may be arranged below the cooking surface. This is particularly advantageous for detecting the boiling point. The sensor module can also be provided positionable in a food container. Preferably, the detected variable is transmitted as a radio signal to the control device.

In a particularly advantageous embodiment, at least two sensor modules

provided, wherein at least one sensor module is adapted and configured to detect at least one electrical parameter of the heater and at least one further sensor module, a vibration sensor and / or acceleration sensor and / or

Sound sensor includes. Such a combination of sensor modules has the advantage that at least two indirect variables can be detected redundantly, resulting in a particularly high reliability in the monitoring of a cooking process. Also possible are two or more identical and / or different sensor modules. For example, at least one sensor module may be provided for an induction device and / or for a cooking location.

The further cooking device according to the invention comprises at least one hob with at least one cooking point and at least one heating device for heating at least one cooking area. At least one sensor device is provided for detecting at least one characteristic variable directly dependent on temperatures of the cooking region and at least one control device. The control device is designed and suitable for controlling the heating device as a function of the at least one variable detected by the sensor device. In this case, the sensor device is associated with at least one sensor module, which is taken from a group of sensor modules. This group includes vibration sensors, acceleration sensors, noise sensors, voltage sensors, current sensors, magnetic field sensors.

This cooking device according to the invention has many advantages. A considerable advantage is the at least one sensor module which is assigned to the sensor device and enables a redundant sensory detection. At least one further variable can be detected by the sensor module in addition to the quantity which is detected by the sensor device and is directly dependent on temperatures of the cooking region. It is particularly advantageous that the sensor module is taken from a group of sensor modules which detect an indirectly dependent on temperatures size, such. B. a noise or a voltage. For example, the cooking device can determine a temperature of the cooking area and redundantly monitor whether there is also a characteristic boiling sound. Thus, the boiling point can be detected particularly reliably during a cooking process. This cooking device can be designed in such a way as previously described for the first-mentioned cooking device.

The inventive method is suitable for operating a cooking device with at least one hob with at least one cooking point and at least one

Heating device for heating at least one cooking area. At least one

Sensor device detects at least one directly dependent on temperatures of the cooking area characteristic size. At least one control device controls the

Heating device at least partially and at least temporarily as a function of at least one of the sensor device detected size. In this case, by means of at least one sensor module associated sensor module at least one indirectly dependent on the temperatures of the cooking area size detected.

The method according to the invention is very advantageous. A particular advantage is that at least one indirectly dependent on temperatures of the cooking area size is detected. Together with the size, which depends directly on the temperature of the cooking area, a cooking process can be monitored very reliably. For example, it can be concluded that the food has boiled, if by means of the direct size a corresponding one

Temperature is determined. The sensor module increases the reliability, for example, by additionally detecting a characteristic boiling sound.

The control device preferably also controls the heating device as a function of the variable detected by the sensor module. This has the advantage that the heater in

Dependence of redundant parameters is controlled and thus can be better adapted to the particular cooking situation. The control device preferably controls the

Heating device at least partially and at least temporarily as a function of detected by the sensor device direct size and detected by the sensor module indirect size.

The characteristic temperature range of a cooking process is preferably determined as a function of the indirectly dependent variable detected by the sensor module and depending on the directly dependent variable detected by the sensor device by means of the control device. As a result, a determined temperature value with an indirectly standing for a temperature value, z. B. a power consumption of the heater to be compared, from which, for example, a boiling plateau can be detected in the cooking process. It is also possible that the characteristic temperature range of a cooking process is determined only as a function of the indirect or the direct size.

It is also preferred that at least one electrical parameter of the heating device is detected by means of the sensor module. In particular, an electrical parameter of a Induction device and / or detected at least one resonant circuit of an induction device. The parameter is in particular an electrical power consumption and / or

Power output and / or an electrical voltage and / or current and / or resistance and / or other electrical or magnetic parameters. The parameter is detected in particular over time and stored at least temporarily. It is also possible that two or more parameters are detected and this particular of the

Control device are charged to another parameter.

In particular, the permeability of the cooking area for a magnetic field is determined as a function of the electrical parameter by means of the control device. The permeability corresponds to the so-called permeability. In particular, at least one cooking product container may be located in the cooking region, wherein preferably also its permeability is determined. Preferably, depending on the permeability over time, a change in temperature of the cooking area or of the food container erected there is determined at least approximately. For this purpose, acquired and / or determined values are stored over at least one period. Based on a decreasing permeability z. B. be closed to an increasing temperature.

In an advantageous embodiment of the method, the characteristic

Temperature range of a cooking process characterized in that at least one value for the permeability with at least one value for a power consumption and / or

Power output of the heater is compared. In particular, a temporal change of the values is considered. The characteristic temperature range is preferably registered as a function of a predetermined deviation of the compared values from one another. For example, the temperature range of a boiling plateau can be registered in this way.

Preferably, the detected direct dependent variable and the detected indirectly dependent variable are weighted differently. In particular, the indirect and the direct size are considered weighted in the control of the heater. But it is also possible that the corresponding sizes are considered equally. In particular, the control device can compare the at least two sizes with each other.

It is also possible that at least one vibration and / or at least one acceleration and / or at least one noise of the cooking area is detected, which characterizes a temperature range of a cooking process and in particular a boiling range. Preferably, at least one sensor module is provided for this purpose.

In a particularly preferred embodiment, the sensor device is designed and suitable for detecting at least a portion of the radiant heat emanating from the cooking area without contact. For this purpose, the sensor device may comprise at least one sensor unit have, for. B. a thermopile or a thermopile. The direct variable is then in particular an output voltage and / or an output current of the sensor unit.

Further advantages and features of the invention will become apparent from the embodiments, which will be explained below with reference to the accompanying figures.

In the figures show:

Figure 1 is a schematic representation of a cooking device according to the invention on a cooking appliance in a perspective view;

Figure 2 is a schematic cooking device in a sectional view;

3 shows a further cooking device in a schematic, sectional view;

4 shows a cooking device with sensor module in a schematic,

cut view; and

Figure 5 is a schematic cooking device with sensor modules in a cut

View.

FIG. 1 shows a cooking device 1 according to the invention, which is here part of a

Cooking appliance 100 is executed. The cooking appliance 1 or the cooking appliance 100 can be designed both as a built-in appliance and as a self-sufficient cooking appliance 1 or stand-alone cooking appliance 100.

The cooking device 1 here comprises a hob 1 1 with four burners 21. Each of the cooking zones 21 here has at least one heated cooking area 31 for cooking food. In order to heat the cooking area 31, a heating device 2, not shown here, is provided in total for each hotplate 21. The heating devices 2 are designed as induction heating sources and each have an induction device 12 for this purpose.

However, it is also possible that a cooking area 31 is not assigned to any particular cooking area 21, but rather represents an arbitrary location on the hob 1 1. In this case, the cooking area 31 may have a plurality of induction devices 12 and in particular a plurality of induction coils and be formed as part of a so-called full-surface induction unit. For example, in such a cooking area 31 simply a pot can be placed anywhere on the hob 1 1, wherein during cooking only the corresponding induction coils are driven in the pot or are active. Other types of heaters 2 are also possible, such. As gas, infrared or

Widerstandsheizquellen. The cooking device 1 can be operated here via the operating devices 105 of the cooking appliance 100. The cooking device 1 can also be designed as a self-sufficient cooking device 1 with its own operating and control device. Also possible is an operation via a

touch-sensitive surface or a touchscreen or remotely via a computer, a smartphone or the like.

The cooking appliance 100 is here designed as a stove with a cooking chamber 103, which can be closed by a cooking chamber door 104. The cooking chamber 103 can be heated by various heat sources, such as a Umluftheizquelle. Other heat sources, such as a

Upper heat radiators and a lower heat radiator, and a Mikrowellenheizquelle or a vapor source and the like may be provided.

Furthermore, the cooking device 1 has a sensor device 3, not shown here, which is suitable for detecting at least one directly dependent on temperatures of the cooking region 31 characteristic size. For example, the sensor device 3 can detect such a direct variable, via which the temperature of a pot can be directly determined, which is turned off in the cooking area 31.

In addition, the sensor device 3 is a sensor module 500 (not illustrated here) for detecting at least one indirectly dependent on temperatures of the cooking region 31

associated with characteristic size. In this case, a sensor device 3 and / or at least one sensor module 500 can be assigned to each cooking area 31 and / or each cooking area 21. It is also possible that a plurality of cooking areas 31 and / or hobs 21st

are provided, but not all of which have a sensor device 3 or a sensor module 500.

The sensor device 3 and the sensor modules 500 are operatively connected to a control device 106 here. The controller 106 is adapted to the heater 2 in

To control dependence of the detected by the sensor device 3 direct size and the detected by the sensor module 500 indirect size.

The cooking device 1 is preferably designed for an automatic cooking operation and has various automatic functions. For example, with the automatic function, a soup can be boiled briefly and then kept warm, without a user having to supervise the cooking process or set a heating level. For this he sets the pot with the soup on a hob 21 and selects the corresponding automatic function via the operating device 105, here z. As a boil with subsequent keeping warm at 60 ° C or 70 ° C or the like.

When using the automatic function is by means of the sensor device 3 during the

Cooking process determines the temperature of the bottom of the pot .. To make it even more reliable To ensure monitoring of the cooking process, for example, the noise development in the cooking area 31 is detected by the sensor module 500. So a boiling of the food can be detected by a characteristic Siedigeräusches. The

Control device 106 registers the noise during the cooking process as well as the temperature of the pot bottom and adjusts the heating power of the heater 2 in

Dependency of the existing values accordingly. When the desired temperature is reached or when the soup boils, the heating power is reduced.

For example, it is also possible by the automatic function to perform a longer cooking process at one or more different desired temperatures, for. B. to slowly let rice pudding draw.

In FIG. 2, a cooking device 1 is strong in a sectional side view

shown schematically. The cooking device 1 here has a carrier device 5 designed as a glass ceramic plate 15. The glass ceramic plate 15 can in particular as

Ceran field or the like may be formed or at least include such. Also possible are other types of support means 5. On the glass ceramic plate 15 is here a cookware or food containers 200, such as a pot or a pan, in which food or food can be cooked.

Furthermore, a sensor device 3 is provided which detects heat radiation in a detection region 83 here. The detection area 83 is in the installed position of

Cooking device 1 is provided above the sensor device 3 and extends upward through the glass ceramic plate 15 to the food container 200 and beyond, if there is no food container 200 is placed there. Below the glass ceramic plate 15 is a

Induction device 12 for heating the cooking area 31 attached. The

Induction device 12 is here annular and has in the middle a recess in which the sensor device 3 is mounted. Such an arrangement of

Sensor device 3 has the advantage that even with a not centrally located on the cooking surface 21 Gargutbehälter 200 this still in the detection range 83 of

Sensor device is.

FIG. 3 shows a schematized cooking device 1 in a sectional side view. The cooking device 1 has a glass ceramic plate 15, below which the

Induction device 12 and the sensor device 3 are mounted.

The sensor device 3 has a first sensor unit 13 and another sensor unit 23. Both sensor units 13, 23 are suitable for non-contact detection of thermal radiation and designed as a thermopile or thermopile. The sensor units 13, 23 are each equipped with a filter device 43, 53 and provided for detecting heat radiation emanating from the cooking area 31. The heat radiation goes for example From the bottom of a Gargutbehälters 200, penetrates the glass ceramic plate 15 and reaches the sensor units 13, 23. The sensor device 3 is advantageously mounted directly below the glass ceramic plate 15 in order to capture as large a proportion of emanating from the cooking area 31 heat radiation without great losses. Thus, the sensor units 13, 23 are provided close to below the glass ceramic plate 15.

Furthermore, a magnetic shielding device 4 is provided, which consists of a ferrite body 14 here. The ferrite body 14 is designed here essentially as a hollow cylinder and surrounds the sensor units 13, 23 in an annular manner

Shielding device 4 shields the sensor device 3 against electromagnetic

Interactions and in particular against the electromagnetic field of the

Induction device 12 from. Without such shielding, the magnetic field generated by induction device 12 during operation could undesirably heat parts of sensor device 3 as well, resulting in unreliable temperature sensing and inferior measurement accuracy. The magnetic shielding device 4 thus considerably improves the accuracy and reproducibility of the temperature detection.

The magnetic shielding device 4 may also consist at least in part of at least one at least partially magnetic material and an at least partially electrically non-conductive material. The magnetic material and the electrically non-conductive material may be arranged alternately and in layers. Also possible are other materials or materials which have at least partially magnetic properties and also have electrically insulating properties or at least low electrical conductivity.

The sensor device 3 has at least one optical screen device 7, which is provided to shield radiation influences and in particular heat radiation, which act on the sensor units 13, 23 from outside the detection zone 83. For this purpose, the optical shield device 7 is designed here as a tube or a cylinder 17, wherein the cylinder 17 is hollow and the sensor units 13, 23 surrounds approximately annular. The cylinder 17 is made of stainless steel here. This has the advantage that the cylinder 17 has a reflective surface which reflects a large proportion of the much heat radiation or absorbs as little heat radiation as possible. The high reflectivity of the surface on the outside of the cylinder 17 is particularly advantageous for the shield against

Thermal radiation. The high reflectivity of the surface on the inside of the cylinder 17 is also advantageous in order to direct thermal radiation from (and in particular only out) the detection area 83 to the sensor units 13, 23. The optical screen device 7 can also be configured as a wall, which surrounds the sensor device 13, 23 at least partially and preferably annularly. The cross section may be round, polygonal, oval or rounded. Also possible is a configuration as a cone. Furthermore, an insulation device 8 for thermal insulation is provided, which is arranged between the optical shield device 7 and the magnetic shielding device 4. The insulation device 8 consists here of an air layer 18, which is between the ferrite 14 and the cylinder 17. Preferably, there is no exchange with the ambient air to avoid convection. But it is also possible an exchange with the ambient air. By the insulation device 8 in particular a heat conduction from the ferrite 14 to the cylinder 17 is counteracted. In addition, the cylinder 17, as already mentioned above, equipped with a reflective surface to counteract heat transfer from the ferrite 14 to the cylinder 17 by heat radiation.

Such an onion-bowl-like arrangement with an external magnetic

Shielding device 4 and an inner optical shield device 7 and an intermediate insulation device 8 provides a particularly good shielding of

Sensor units 13, 23 against radiation from outside of the detection range 83. This has a very beneficial effect on the reproducibility or reliability of

Temperature detection off. The insulation device 8 has, in particular, a thickness of between approximately 0.5 mm and 5 mm and preferably a thickness of 0.8 mm to 2 mm and particularly preferably a thickness of approximately 1 mm.

The isolation device 8 may also be at least one medium with a correspondingly low heat conduction, such. B. include a foam material and / or a polystyrene plastic or other suitable insulating material.

The sensor units 13, 23 are arranged here on a thermal compensation device 9 thermally conductive and in particular thermally conductive with the thermal

Balancing device 9 coupled. The thermal compensation device 9 has for this purpose two coupling devices, which are formed here as depressions, in which the

Sensor units 13, 23 are embedded accurately. This ensures that the sensor units 13, 23 are at a common and relatively constant temperature level. In addition, the thermal compensation device 9 ensures a homogeneous

Own temperature of the sensor unit 13, 23, when heated in the operation of the cooking device 1. An unequal own temperature can in particular as a thermopile

trained sensor units 13, 23 lead to artifacts in the detection. To avoid heating the thermal compensation device 9 by the cylinder 17, a spacing between cylinder 17 and thermal compensation device 9 is provided. The copper plate 19 may also be provided as the bottom 27 of the cylinder 17.

To enable a suitable thermal stabilization, the thermal

Compensation device 9 is formed here as a solid copper plate 19. It is possible also at least partly another material with a correspondingly high heat capacity and / or a high thermal conductivity.

The sensor device 3 here has a radiation source 63, which can be used to determine the reflection properties of the measuring system or the emissivity of a food container 200. The radiation source 63 is here designed as a lamp 1 1 1, which emits a signal in the wavelength range of the infrared light and the visible light. The radiation source 63 may also be formed as a diode or the like. The lamp 1 1 1 is used here in addition to the reflection determination for signaling the operating state of the cooking device 1.

In order to focus the radiation of the lamp 1 1 1 on the detection area 83, a portion of the thermal compensation device 9 and the copper plate 19 is formed as a reflector. For this purpose, the copper plate 19 has a concave-shaped depression, in which the lamp 1 1 1 is arranged. The copper plate 19 is also coated with a gold-containing coating to increase the reflectivity. The gold-containing layer has the advantage that it also protects the thermal compensation device 9 from corrosion.

The thermal compensation device 9 is executed on a plastic holder

Holding device 10 attached. The holding device 10 has a connecting device, not shown here, by means of which the holding device 10 can be latched to a support means 30. The support device 30 is formed here as a printed circuit board 50. On the support means 30 and the circuit board 50 also other components may be provided, such. As electronic components, control and computing devices and / or mounting or mounting elements.

Between the glass ceramic plate 15 and the induction device 12 is a

Sealing device 6 is provided, which is designed here as a micanite layer 16. The micanite layer 16 is used for thermal insulation, so that the induction device 12 is not heated by the heat of the cooking area 31. In addition, a micanite layer 16 for thermal insulation between the ferrite body 14 and the glass-ceramic plate 15 is provided here. This has the advantage that the heat transfer from the hot in the glass ceramic plate 15 to the ferrite 14 is severely limited. This goes from the

Ferrite body 14 hardly heat, which could be transferred to the isolation device 8 or the optical shield device. The micanite layer 16 thus counteracts an undesirable heat transfer to the sensor device 3, which increases the reliability of the measurements. In addition, the micanite layer 16 seals the sensor device 3 dust-tight against the remaining regions of the cooking device 1. The micanite layer 16 has

in particular a thickness between about 0.2 mm and 4 mm, preferably from 0.2 mm to 1, 5 mm and particularly preferably a thickness of 0.3 mm to 0.8 mm. The cooking device 1 has on the underside a cover 41, which is designed here as an aluminum plate and the induction device 12 covers. The

Covering device 41 is connected to a housing 60 of the sensor device 3 via a

Screw 122 connected. Within the housing 60, the sensor device 3 is arranged elastically relative to the glass ceramic plate 15. For this purpose, a damping device 102 is provided, which here has a spring device 1 12.

The spring device 1 12 is connected at a lower end to the inside of the housing 60 and at an upper end to the circuit board 50. In this case, the spring device 1 12 presses the printed circuit board 50 with the ferrite 14 and the attached thereto micanite 16 up against the glass ceramic plate 15. Such an elastic arrangement is particularly advantageous because the sensor device 3 may be arranged as close as possible to the glass ceramic plate 15 for metrological reasons should. This directly adjacent arrangement of

Sensor device 3 on the glass ceramic plate 15 could cause damage to the glass ceramic plate 15 in the event of impacts or impacts. Due to the elastic reception of the sensor device 3 relative to the carrier device 5, shocks or impacts are damped on the glass ceramic plate 15 and thus reliably prevent such damage.

An exemplary measurement in which the temperature of the bottom of a on the

Glass ceramic plate 15 standing pot to be determined with the sensor device 3 is briefly explained below:

During the measurement, the first sensor unit 13 detects outgoing from the bottom of the pot

Heat radiation as mixed radiation together with the heat radiation, which is emitted from the glass ceramic plate 15. In order to be able to determine therefrom a radiation power of the pot bottom, the proportion of the emanating from the glass ceramic plate 15

Radiation power out of the mixed radiation power. In order to determine this proportion, the other sensor unit 23 is provided to detect only the heat radiation of the glass-ceramic plate 15. For this purpose, the other sensor unit 23 has a

Filter device 53, which substantially only radiation with a wavelength greater than 5 μηη to the sensor unit 23 durchläset. The reason for this is that radiation with a wavelength greater than 5 μηη is not or hardly transmitted by the glass ceramic plate 15. The other sensor unit 23 thus essentially detects the heat radiation emitted by the glass ceramic plate 15. With the knowledge of the portion of the heat radiation, which of the

Glass ceramic plate 15 is emitted, can be determined in per se known, the proportion of heat radiation, which emanates from the bottom of the pot.

For a good measurement result, it is desirable for as much of the heat radiation emanating from the bottom of the pot to reach the first sensor unit 13 and to be detected by it. For radiation in the wavelength range of about 4 μηη has the Glass ceramic plate 15 here has a transmission of about 50%. Thus, in this wavelength range, a large part of the heat radiation emanating from the bottom of the pot can pass through the glass-ceramic plate 15. Detection in this wavelength range is therefore particularly favorable. Accordingly, the first sensor unit 13 is equipped with a filter device 43 which is very permeable to radiation in this wavelength range, while the filter device 43 substantially reflects radiation from other wavelength ranges. The filter devices 43, 53 are each designed here as an interference filter and in particular as a bandpass filter or as a longpass filter.

The determination of a temperature from a specific radiant power is a known method. The decisive factor is that the emissivity of the body is known, from which the temperature is to be determined. In the present case, therefore, the emissivity of the pot bottom must be known or determined for a reliable temperature determination. The sensor device 3 here has the advantage that it is designed to determine the emissivity of a Gargutbehälters 200. This is particularly advantageous, since thus any cookware can be used and not just a specific food container whose emissivity must be known in advance.

In order to determine the emissivity of the pot bottom, the lamp 1 1 1 emits a signal which has a proportion of heat radiation in the wavelength range of the infrared light. The radiation power or the thermal radiation of the lamp 1 1 1 passes through the

Glass ceramic plate 15 on the bottom of the pot and is there partially reflected and partially absorbed. The reflected radiation passes through the glass ceramic plate 15 back to the sensor device 3, where it from the first sensor unit 13 as mixed radiation from

Pot bottom and is detected by the glass ceramic plate 15. At the same time as the reflected signal radiation, therefore, the own thermal radiation of the pot bottom and the glass ceramic plate also reaches the first sensor unit 13. Therefore, the lamp 11 is then switched off and only the thermal radiation of the pot bottom and the glass ceramic plate is detected. The proportion of the reflected signal radiation then results in principle from the previously detected total radiation minus the thermal radiation of the pot bottom and the glass ceramic plate.

With knowledge of the proportion of reflected from the bottom of the pot signal radiation of the

Absorbency of the pot bottom and thus its emissivity can be determined in a known manner, since the absorption capacity of a body in principle the

Emissivity of a body and the proportion of absorbed by the pot

Radiation equals 1 minus reflected radiation.

The emissivity is redetermined here at certain intervals. This has the advantage that a subsequent change in the emissivity does not lead to a falsified measurement result. A change in the emissivity can occur, for example, when the Cookware tray has different emissivities and is moved to the hob 21. Different emissivities are very common in cookware trays observed because z. B. already light soiling, corrosion or even different coatings or coatings can have a major impact on the emissivity.

The lamp 1 1 1 is used here in addition to the determination of the emissivity or the determination of the reflection behavior of the measuring system for signaling the operating state of the cooking device 1. In this case, the signal of the lamp 1 1 1 also includes visible light, which is perceptible by the glass ceramic plate 15. For example, the lamp 1 1 1 indicates to a user that an automatic function is in operation. Such an automatic function can, for. B. be a cooking operation, in which the heater 2 is controlled automatically in dependence of the determined pot temperature. This is particularly advantageous because the lighting of the lamp 1 1 1 does not confuse the user. The user knows from experience that the lighting is an operation indicator and the normal appearance of the

Cooking device 1 belongs. He can therefore be sure that a flashing of the lamp 1 1 1 is not a malfunction and the cooking device 1 may not work properly.

The lamp 1 1 1 can also light up in a certain duration and at certain intervals. It is possible z. As well as that over different flashing frequencies

different operating states can be output. Different signals are also possible via different on / off sequences. Advantageously, a sensor device 3 with a radiation source 63, which is suitable for displaying at least one operating state, is provided for each cooking point 21 or each (possible) cooking region 31.

At least one arithmetic unit may be provided for the necessary calculations for determining the temperature and for the evaluation of the detected variables. The arithmetic unit can be at least partially provided on the circuit board 50. However, it is also possible, for example, for the control device 106 to be designed accordingly, or at least one separate arithmetic unit is provided.

FIG. 4 shows a development in which a sensor module 500 and a safety sensor 73 are arranged below the glass-ceramic plate 15. The safety sensor 73 is formed here as a temperature-sensitive resistor, such as a thermistor or an NTC sensor, and thermally conductively connected to the glass ceramic plate 15. The safety sensor 73 is provided here to be able to detect a temperature of the cooking area 31 and in particular of the glass ceramic plate 15. If the temperature exceeds a certain value, there is a risk of overheating and the heaters 2 are switched off. For this purpose, the safety sensor 73 with a not shown here Safety device operatively connected, which can trigger a safety state depending on the detected temperature. Such a security condition has z. B. the shutdown of the heaters 2 and the cooking device 1 result.

In addition, the safety sensor 73 is here as another sensor unit 33 of

Sensor device 3 assigned. In this case, the values detected by the safety sensor 73 are also taken into account for the determination of the temperature by the sensor device 3. In particular, when determining the temperature of the glass-ceramic plate 15, the values of the safety sensor 73 are used. So z. B. the temperature, which was determined by means of the other sensor unit 23 on the detected thermal radiation, are compared with the temperature detected by the safety sensor 73. This adjustment can on the one hand serve to control the function of the sensor device 3, but on the other hand can also be used for a tuning or adjustment of the sensor device 3.

The task of the other sensor unit 23 can also be taken over by the safety sensor 73 in an embodiment not shown here. The safety sensor 73 serves to determine the temperature of the glass ceramic plate 15. For example, with knowledge of this temperature from the heat radiation, which detects the first sensor unit 13, the proportion of a pot bottom can be determined. Such a configuration has the advantage that the other sensor unit 23 and an associated filter device 53 can be saved.

The sensor module 500 is embodied here as a vibration sensor 502 and likewise arranged below the glass-ceramic plate 15. Through this positioning vibrations and noises can be detected which are particularly good from a food container 200 in the

Cooking area 31 go out. For example, the vibration sensor 502 has one

piezoelectric sensor, which converts the applied vibrations into a voltage. The voltage is passed as an output to the controller 106 and charged by this to detect a characteristic vibration of the cooking process, for. B the sound of a bubble boiling.

FIG. 5 schematically shows a cooking device 1 with two sensor modules 500 in a sectional side view. On the glass ceramic plate 15 is a

Gargutbehälter 200. Below the glass ceramic plate 15 is an induction device 12 which has a recess in the middle, in which a sensor device 3 is arranged. The induction circuit unit 32 together with the induction coil 22 forms the resonant circuit for generating the electromagnetic alternating field. In addition, the induction circuit unit 32 controls the oscillation circuit according to the requirements of the cooking process. The one sensor module 500 is designed as a vibration sensor 502, as has already been described in FIG. The further sensor module 500 detects here an electrical parameter of the induction device 12 and is designed as a voltage sensor 501. The output signals of the sensor modules 500 are registered by the control device 106 and charged. The control device 106 takes this information into account in the regulation of the heating power of the induction device 12.

Here, the voltage sensor 501 is a sensor which is regularly provided in the induction device 12, for example to be able to monitor the voltage in the oscillating circuit and accordingly regulate the heating power or also to detect whether or not a food container 200 is located in the cooking area 31 (so-called pan detection) ). This can save costs for an additional voltage sensor. Of the

Voltage sensor 501 is integrated here in an electronic circuit of the induction circuit unit 32. Two or more voltage sensors 501 and / or other sensors for detecting electrical and / or magnetic parameters in the induction circuit unit 32 may also be provided. It is also possible for corresponding values for the voltage and for other variables to be tapped at different points in the induction circuit unit 32, which values are at least partially used as an indirect quantity

Find use.

On the basis of the detected voltage and corresponding further electrical parameters of the resonant circuit, the permeability to a magnetic field (the so-called permeability) of a cooking utensil 200 positioned in the cooking region 31 or its pot bottom is determined. The permeability changes depending on the temperature of the pot bottom. As a result of the variable detected by the voltage sensor 501, temperatures or a temperature change in the cooking region 31 can be indirectly deduced.

The calculated permeability can also be advantageously used to monitor the cooking process, for example, to determine whether the food boils or not.

In particular, aqueous food items are characterized by a boiling plateau at the boiling point. In a Siedeplateau further power is supplied to the food, the temperature does not change or only barely. The boiling plateau is then recognized by the fact that the temperature and thus the permeability does not change substantially over time or compared to a previous period, while the power output of the induction device 12 remains substantially the same over time. To determine the power output, further electrical parameters of the induction device 12 can be tapped or sensed.

A Siedeplateau can also be recognized that the power output over time with the detected by the sensor device 3 direct size, eg. B. the heat radiation, and the temperature determined therefrom of the cooking area 31 is compared. Give the Induction device 12 continues power from and while the temperature in the cooking area 31 is substantially unchanged, a boiling plateau can be assumed.

The presented cooking device 1 provides reliable monitoring of automatically controlled cooking or frying. A sensor device 3 allows an accurate and reproducible determination of the temperature of the cooking area 31 during the

Cooking. In this case, the sensor device 3 detects outgoing from the bottom of the pot

Heat radiation, which depends directly on the temperature of the pot bottom. In addition, by means of sensor modules 500 still vibrations, Siedigeräusche and

Permeability changes of the pot bottom as well as other characteristics of a cooking phase, such. B. a Siedeplateau determined. This information is all brought together and taken into account in the regulation of the heating power of the induction device. Due to the manifold and partially redundant information, automatic operation is particularly practicable and reliable.

LIST OF REFERENCE NUMBERS

1 cooking facility

2 heating device

3 sensor device

4 magnetic shielding device

5 carrier device

6 sealing device

7 optical screen device

8 insulation device

9 thermal compensation device

10 holding device

1 1 hob

12 induction device

13 sensor unit

14 ferrite bodies

15 glass ceramic plate

16 Micanite shift

17 cylinders

18 air layer

19 copper plate

21 hotplate

22 induction coil

23 sensor unit

27 floor

30 support device

31 cooking area

32 induction circuit unit

33 sensor unit

41 Covering device

43 Filter device

50 circuit board

53 Filter device

60 housings

63 radiation source

73 safety sensor

83 detection area

100 cooking appliance

102 damping device 103 cooking space

104 cooking chamber door

105 Operating device

106 control device

1 1 1 lamp

1 12 spring device

122 screw connection

200 food containers

500 sensor module

501 voltage sensor

502 vibration sensor

Claims

claims

1. cooking device (1) with at least one hob (1 1) with at least one

Cooking area (12) and with at least one heating device (2) for heating at least one cooking area (31)

and at least one sensor device (3) for detecting at least one characteristic variable directly dependent on temperatures of the cooking region (31), and at least one control device (106) being provided,

which is designed and suitable for controlling the heating device (2) as a function of the at least one variable detected by the sensor device (3),

characterized in that

at least one sensor module (500) is associated with the sensor device (106) for detecting at least one variable which is indirectly dependent on temperatures of the cooking region (31).

2. Cooking device (1) according to the preceding claim, characterized in that the control device (106) is suitable and designed to control the heating device (2) also in dependence of the detected by the sensor module (500) size.

3. Cooking device according to one of the preceding claims, characterized in that the control device (106) is suitable and designed, based on at least one of the sensor device (3) and / or the sensor module (500) detected size at least a characteristic temperature range of a cooking operation determine.

4. cooking device (1) according to one of the preceding claims, characterized

characterized in that the control device (106) is suitable and designed to recognize at least one characteristic temperature range of a cooking process and in particular a boiling plateau in dependence on a change in the detected indirectly dependent variable over time.

5. cooking device (1) according to one of the preceding claims, characterized

in that the sensor module (500) is suitable and designed to detect at least one electrical parameter of the heating device (2).

6. cooking device (1) according to one of the preceding claims, characterized

in that the sensor module (500) has at least one vibration sensor (502) and / or at least one acceleration sensor and / or at least one Noise sensor and / or at least one voltage sensor (501) and / or at least one current sensor and / or at least one magnetic field sensor.

7. cooking device (1) according to one of the preceding claims, characterized

in that the hob (1 1) has at least one carrier device (5) for positioning at least one food container (200) and that the

Sensor module (3) in installation position of the hob (1 1) at least partially below the support means (5) is arranged.

8. cooking device (1) with at least one hob (1 1) with at least one

characterized in that

the sensor device (3) is associated with at least one sensor module (500) which is taken from a group of sensor modules comprising vibration sensors (502), acceleration sensors, noise sensors, voltage sensors (501), current sensors, magnetic field sensors.

9. A method for operating a cooking device (1) having at least one hob (1 1) with at least one cooking point (12) and at least one heating device (2) for heating at least one cooking area (31)

and at least one sensor device (3) which detects at least one characteristic variable directly dependent on temperatures of the cooking region (31), and wherein at least one control device (106) controls the heating device (2) at least partially and at least temporarily as a function of the at least one of the Sensor device (3) detects detected size,

characterized in that

by means of at least one of the sensor device (3) associated sensor module (500) at least one indirectly of temperatures of the cooking area (31) dependent size is detected.

10. The method according to the preceding claim, characterized in that the control device (106) controls the heating device (2) as a function of the size detected by the sensor module (500).

1 1. The method according to any one of the preceding claims, characterized in that in dependence of the indirectly dependent variable detected by the sensor module (500) and / or depending on the directly dependent size detected by the sensor device (3) by means of the control device (106) characteristic temperature range of a cooking process is determined.

12. The method according to the preceding claim, characterized in that by means of the sensor module (500) at least one electrical parameter of the heating device (2) is detected.

13. Method according to the preceding claim, characterized in that the permeability of the cooking area (31) for a magnetic field is determined in dependence on the electrical parameter by means of the control device (106).

14. Method according to the preceding claim, characterized in that

in dependence on a comparison of at least one value for the permeability with at least one value for a power consumption and / or power output of the heating device (2), the characteristic temperature range of a cooking process is determined.

15. The method according to any one of the preceding claims, characterized in that the detected directly dependent variable and the detected indirectly dependent variable are weighted differently.

16. The method according to any one of the preceding claims, characterized in that at least one vibration and / or at least one acceleration and / or at least one noise of the cooking area is detected, which / which characterizes a temperature range of a cooking process and in particular a boiling range.