Method for setting microwave power

Abstract

The invention relates to a method of setting microwave power, in particular to a method of setting microwave power in a cooking appliance (10), the method comprising the steps of: specifying a microwave factor; introducing thermal energy into a cooking chamber (14) of the cooking appliance (10); determining a heat consumption of thermal energy in the cooking chamber (14); and setting the microwave power based on the microwave factor and the thermal energy consumption in the cooking chamber (14). The invention also relates to a cooking appliance (10).

Description

Field of the Invention

[0001] The present invention relates to a method for setting the microwave power in a cooking appliance. The present invention also relates to a cooking appliance. Background Art

[0002] In a professional kitchen or a canteen kitchen, cooking appliances are used that are suitable for cooking cooking products in different ways, and the cooking products are present in the cooking chamber of the cooking appliance. In addition to the conventional methods of using hot air and / or steam to cook the cooking products, modern cooking appliances usually also use a microwave source that introduces energy into the cooking products by means of electromagnetic radiation to (additionally) heat the cooking products. Vacuum tubes (e.g., magnetrons) and semiconductor components can be used as microwave sources.

[0003] In many conventional cooking appliances, the user must specify the microwave power for each cooking process. For example, the user can set the microwave power on the appliance in stages between 0% and 100%. A setting at the maximum level or 100% usually causes the microwave source to radiate into the cooking chamber at its full nominal power (e.g., 2 kW).

[0004] During the setting, the user must decide for themselves which microwave power is optimal for the cooking process. The user must consider influencing factors such as the load quantity and the degree of heating based on their experience and / or their own assessment. Therefore, setting the optimal microwave power involves a great deal of effort and is also error-prone.

[0005] If the microwave power is too low, the cooking process may take an unnecessarily long time. However, if the microwave power is set too high, this may result in drying out, insufficient crust formation, and / or poor energy efficiency of the cooking process. Summary of the Invention

[0006] Therefore, an object of the present invention is to provide a simple and cost-effective possibility of preventing incorrect setting of the microwave power during cooking, especially during a manual cooking process, and thus ensuring good and reproducible cooking results.

[0007] According to the present invention, this object is achieved by a method for setting the microwave power in a cooking appliance. The method comprises the following steps:

[0008] - specifying a microwave factor M;

[0009] - introducing thermal energy into the cooking chamber of the cooking appliance;

[0010] - determining the heat consumption of the thermal energy in the cooking chamber; and

[0011] - setting the microwave power P based on the microwave factor M and the heat consumption in the cooking chamber MW .

[0012] The term "heat consumption" (also known as heat loss) refers to the consumption of thermal energy in the cooking chamber, such as the consumed part of the thermal energy introduced into the cooking chamber or the part caused by the introduction of cooled (frozen) cooking products. In particular, it can also be the part consumed in or by the cooking chamber within a certain time. Heat consumption can also occur due to the absorption of thermal energy by the cooking products. This is a typical situation during operation, provided that no additional cooking products are introduced.

[0013] The basic idea of the present invention is to set the microwave power as a relative value depending on the heat consumption in the cooking chamber, rather than as an absolute value.

[0014] Thus, a user-friendly and self-regulating system is created that is suitable for dynamically reacting to the amount of load and / or changes in the load in the cooking chamber.

[0015] It is also possible to reliably avoid unnecessary high microwave power and / or temperature in the cooking chamber that may cause damage to components (especially in the case of small loads) through the amount of microwave radiation related to heat consumption.

[0016] Since it is set as a relative value, microwave power can also be automatically considered when controlling the temperature in the cooking chamber. Therefore, the microwave power can increase or decrease synchronously with the heating power of other components of the cooking appliance, which also helps to improve the cooking quality and / or avoid unsuccessful cooking processes. These components can also introduce energy into the cooking products. The components involve, for example, an infrared heat source, a hot air source, and / or a steam source also known as a steam generator.

[0017] In particular, a control and / or evaluation unit is provided that determines the heat consumption and sets the microwave power P based on the microwave factor M and the heat consumption of the cooking products in the cooking chamber in particular. MW 。

[0018] One aspect of the present invention provides that the heat consumption is characterized by the heat consumption power P Abs . The part of the heat consumption power P Abs directly absorbed by the cooking products is also referred to as the power P absorbed in the cooking products GG . In other words, the focus is not on the total amount of energy consumed, but on how much energy or heat is consumed in or by the cooking products within a certain time. It has been shown that the heat consumption power is very suitable as a reference value for setting the microwave power because, on the one hand, the heat consumption power contains important information about the cooking state of the cooking products (cooler cooking products usually absorb heat faster than hotter cooking products), and on the other hand, the heat consumption power can be determined in a reliable and reproducible manner.

[0019] In a preferred embodiment, the microwave power is set to a value corresponding to the product of the heat consumption power, in particular the power P absorbed by the cooking product GG and the microwave factor (P MW = M * P GG ). This is technically particularly easy to implement and less error-prone.

[0020] The heat consumption, in particular the heat consumption power, can be determined based on the average heating power of at least one heating device of the cooking appliance. In this context, it is conceivable that during the cooking operation, the cooking chamber temperature remains at least approximately constant over a certain period of time. Then, the total average heating power applied by the radiant heating device during this period (apart from any power losses) directly corresponds to the heat consumption power.

[0021] Additionally or alternatively, the heat consumption or the heat consumption power can also be determined based on the temperature change and / or humidity change in the cooking chamber. For this purpose, temperature and / or humidity sensors that are usually provided anyway in a conventional cooking appliance can be used in particular. Thus, no additional specific hardware is required.

[0022] Ideally, the heat consumption is determined based on a combination of the heating activity and the changes in temperature and / or humidity.

[0023] In a variant of this method, it is provided to determine the heat consumption or the heat consumption power based on the heating power introduced into the cooking chamber.

[0024] Based on the heat consumption power of the cooking chamber with the existing load, in turn, the power absorbed by the cooking product can be determined by taking into account any power losses. The power losses can be a part of the introduced power that causes the heating of the cooking chamber housing (also referred to as housing losses below) and thus is no longer available for heating the cooking product.

[0025] In short, the heat consumption or the heat consumption power used as a reference value for setting the microwave power can thus be the part of the introduced heat power actually absorbed by the cooking product.

[0026] The power losses considered in this method can be specified and / or experimentally determined values.

[0027] In particular, the housing losses can be determined in an independent test depending on the appliance and / or can be stored in the memory of the cooking appliance. Then, the experimentally determined power loss value can be simply obtained from the memory to determine the heat consumption.

[0028] Of course, more than one power loss value can be stored in the memory of the cooking appliance.

[0029] In particular, it can be thought that the power loss is a value that depends on the cooking chamber temperature process. For example, in the case of heating the cooking chamber (dynamic case), a power loss value is expected. In such a case, a large part of the introduced energy causes heating of the cooking chamber itself, especially the cooking chamber housing, and thus is not available for directly heating the cooking product. The power loss depends on the previously set cooking chamber temperature and / or the temperature change. However, in a stationary or static situation, that is, when maintaining a specified cooking chamber temperature and assuming a heated housing, the thermal power loss only depends on the temperature-dependent heat transfer coefficient of the housing and the difference between the cooking chamber temperature and the ambient temperature.

[0030] Taking this into account, a plurality of power loss values at different expected cooking chamber temperatures can be stored in the memory of the cooking appliance.

[0031] Another aspect of the present invention provides for taking into account the operating state of one or more fan impellers of the cooking appliance when determining the heat consumption.

[0032] In many modern cooking appliances, a change in the rotation direction of the fan is provided to equalize the cooking chamber climate. They can cause a changed air flow and thus a change in the measured cooking chamber temperature and / or a changed heat consumption of the cooking product. By correspondingly taking into account the operating state of the fan impeller, such as the current rotation direction and / or the change in the rotation direction, the accuracy of the method can be improved.

[0033] In a further variant of the method, the microwave factor can be specified by the user. It is conceivable that the user inputs the microwave factor as a numerical value via the input device or can select the microwave factor from a specified selection. In this way, the user maintains control over the cooking process. At the same time, it is ensured that no significant overuse or underuse of the microwave power occurs.

[0034] For certain cooking processes, the microwave factor can be fixed because the cooking appliance manufacturer has experimentally determined the optimal microwave factor specific to the cooking product during a previous development process. Such cooking processes can be so-called intelligent cooking processes or cooking processes specific to the cooking product.

[0035] Furthermore, the present invention relates to a cooking appliance that includes a cooking chamber and at least one microwave module, the at least one microwave module being configured and arranged to feed electromagnetic radiation into the cooking chamber to cook a cooking product introduced into the cooking chamber by means of microwave energy. The cooking appliance has a control and / or evaluation unit that is configured and arranged to execute a computer program that has program code means for performing the method according to the present invention. The advantages discussed with respect to the method are correspondingly applicable to the cooking appliance. Description of the Drawings

[0036] Additional features and advantages of the present invention will become apparent from the following description and from the accompanying drawings, in which:

[0037] - Figure 1 a schematic representation of a cooking appliance loaded with a cooking product according to the present invention is shown; and

[0038] - Figure 2 a graphical illustration of a microwave power curve relative to a heat consumption power is shown. DETAILED DESCRIPTION

[0039] Figure 1 An exemplary embodiment of a cooking appliance 10 loaded with a cooking product 12 to be cooked according to the present invention is shown. The cooking appliance 10 has a cooking chamber 14 and at least one (preferably a plurality of) microwave modules 16. For simplicity, only one microwave module 16 is shown in Figure 1 .

[0040] At least one microwave module 16 includes a solid state microwave generator (SSMG) and is configured and arranged to feed a microwave beam into the cooking chamber 14. The microwave beam may have a frequency suitable for heating the cooking product 12 present in the cooking chamber 14. This frequency is, for example, between 2.1 GHz and 2.8 GHz, particularly between 2.4 GHz and 2.5 GHz, preferably about 2.45 GHz.

[0041] To feed into the cooking chamber 14, at least one microwave module 16 may be equipped with an antenna and a directional coupler (not shown). However, several antennas and directional couplers may also be provided for each microwave module 16.

[0042] In addition, at least one microwave module 16 may include additional components or parts, such as a modulator, an amplifier, a demodulator, and / or a controller (not shown).

[0043] In the exemplary embodiment, the cooking appliance 10 is a combination appliance, which, in addition to at least one microwave module 16, also has different additional components for cooking the cooking product 12, particularly a thermal heating device 18, such as an infrared heating source 20, and a hot air and / or steam source 22. Of course, this should not be understood in a restrictive way. Other types of heating devices 18 are also conceivable.

[0044] Furthermore, the cooking appliance 10 includes: at least one temperature sensor 24 by means of which the cooking chamber temperature can be detected; an optional humidity sensor 25 for detecting the humidity in the cooking chamber 14; and a reversibly operable fan impeller 26 by means of which the cooking chamber atmosphere can be mixed.

[0045] Furthermore, Figure 1 the cooking appliance 10 shown has an input device 28, such as a touch display, by means of which the user can make inputs, in particular (manually) select a cooking program or set and / or adjust desired cooking parameters.

[0046] In addition, the cooking appliance 10 in the exemplary embodiment has a control and / or evaluation unit 30 connected to at least one microwave module 16, and a memory 32 in which a computer program with program code means is stored. When the computer program is executed by a processor unit (not shown) of the cooking appliance 10, the computer program causes the control and / or evaluation unit 30 to implement a method for setting the microwave power. This method is described in more detail below.

[0047] At the start of the method, the cooking product 12 is introduced into the cooking chamber 14 of the cooking appliance 10 or the cooking product 12 is already present in the cooking chamber 14 of the cooking appliance 10.

[0048] In a first step of the method, a microwave factor M is specified. This can be done in particular by a user input by means of the input device 28. The microwave factor M is, for example, a value manually entered by the user or selected from a plurality of specified values.

[0049] The user can make the input in particular before the start of the cooking process. Alternatively, it is also conceivable to make the input during an ongoing cooking process.

[0050] For certain cooking processes, the microwave factor M can be fixed because the cooking appliance manufacturer has (experimentally) determined the optimal microwave factor specific to the cooking product during a previous development process. These specific cooking processes can be so-called intelligent cooking processes or cooking processes specific to the cooking product.

[0051] In a second step of the method, thermal energy is introduced into the cooking chamber 14 of the cooking appliance 10 by means of the thermal heating device 18. Of course, not all of the above heating devices 18 must be activated simultaneously. For example, it is sufficient if only the infrared heating source 20 or only the hot air and / or steam source 22 introduces thermal energy into the cooking chamber 14.

[0052] In a third step of the method, the control and / or evaluation unit 30 determines the thermal consumption of the thermal energy in the cooking chamber 14.

[0053] In the exemplary embodiment, the control and / or evaluation unit 30 determines a thermal consumption power P characterizing the thermal consumption in the cooking chamber 14 for this purpose Abs .

[0054] In short, the control and / or evaluation unit 30 thus determines, for example, the part of the introduced thermal energy that is consumed in or by the cooking chamber 14 over a certain period of time.

[0055] In an exemplary embodiment, the heat consumption or heat consumption power is determined based on the average heating power of the activated heating devices 18 of the cooking appliance 10. For this purpose, for example, the electrical energy absorbed for operating the infrared heating source 20 and / or the hot air or steam source 22 is detected and evaluated (depending on which of the heating devices 18 are activated).

[0056] Alternatively, the heat consumption or heat consumption power can also be determined based on the temperature and / or humidity change in the cooking chamber 14, which can be determined by means of the temperature sensor 24 or the humidity sensor 25.

[0057] It is also possible to combine the two variants for determining the heat consumption in the cooking chamber 14.

[0058] In an exemplary embodiment, the control and / or evaluation unit 30 determines the power P V absorbed by the cooking product 12 based on the heat consumption power of the cooking appliance 10 and the power loss P GG .

[0059] The power loss is the part of the total thermal power introduced into the cooking chamber 14 that does not directly contribute to the cooking of the cooking product 12 (e.g., housing losses).

[0060] In an exemplary embodiment, the power loss depends on the cooking chamber temperature. Thus, in this method, the control and / or evaluation unit 30 takes into account the power loss as a function of the temperature in the cooking chamber. For this purpose, experimentally determined power loss values for different cooking chamber temperatures are stored in the memory 32 of the cooking appliance 10. Depending on the currently prevailing cooking chamber temperature or the cooking chamber temperature measured by the temperature sensor 24, an appropriate power loss value is obtained from the memory 32.

[0061] Then, the power P Abs absorbed by the cooking product 12 can be calculated in particular based on the following formula as the difference between the heat consumption power P V and the power loss P GG : P GG = P Abs - P V .

[0062] In addition, when determining the heat consumption or heat consumption power, the operating state of the fan impeller 26 (e.g., change in the rotation direction or agitation power) can also be explicitly considered. However, the operating state of the fan impeller 26 can also be indirectly considered, in particular, by the influence of the fan impeller operation on the heat consumption in the cooking chamber 14. By means of the fan impeller 26, the air layer surrounding the cooking product 12, i.e., the so-called microclimate in the cooking chamber 14, can be vortexed.

[0063] In the fourth step of the method, the control and / or evaluation unit 30 sets the microwave power P based on the microwave factor M and the heat energy consumption or heat consumption power in the cooking chamber 14, in particular the power absorbed by the cooking product 12. MW .

[0064] In an exemplary embodiment, the control and / or evaluation unit 30 calculates, for this purpose, according to the formula P MW = M * P GG a value corresponding to the product of the power P GG absorbed by the cooking product 12 and the microwave factor M, and adjusts the power of at least one microwave module 16 such that at least one microwave module 16 radiates microwaves into the cooking chamber 14 with the calculated power value.

[0065] Figure 2 Schematically shows possible microwave power curves varying with the heat consumption power for different microwave factors.

[0066] In an exemplary embodiment, the microwave power P MW is proportional to the power P GG absorbed by the cooking product 12. The proportionality factor is the microwave factor M. For example, the following formula relationship can be given: P MW = M * P GG = M * P Abs - M * P V . As already explained above, P Abs is the heat power absorbed in the cooking chamber 14, and P V is the power loss.

[0067] In this case, Figure 2 the slope of the shown microwave power curve corresponds to the microwave factor.

[0068] Figure 2 Shows a first microwave power curve 34 where the microwave factor is 1. Shows a second microwave power curve 36 where the microwave factor is 0.5. In the shown third microwave power curve 38, the microwave factor is 0.25, in the shown fourth microwave power curve 40, the microwave factor is 0.1, and in the shown fifth microwave power curve 42, the microwave factor is 0.05.

[0069] As can be seen from Figure 2 it, the user can thus determine how quickly or strongly the microwave power can increase during the cooking process by specifying the microwave factor M.

[0070] Of course, this increase cannot occur in an unlimited manner. In Figure 2 it, the microwave power curve is limited at the upper part by the nominal power 44 (for example, 2 kW) of at least one microwave module 16.

[0071] As Figure 2 shown, a threshold value 46 can also be set for the microwave power at the lower part. Thus, it can be conceived that, for technical and / or energy efficiency reasons, at least one microwave module 16 will only feed microwaves into the cooking chamber 14 when the lower threshold 46 is exceeded.

[0072] In an exemplary embodiment, this can be achieved in practice because at least one microwave module 16 is only activated when the product of the microwave factor and the heat consumption power produces a value higher than the threshold 46. Alternatively, microwave power below the threshold can also be achieved by the timing of a suitable microwave module 16.

Claims

1. A method for setting microwave power in a cooking appliance (10), the method comprising the following steps: -Specify microwave factors; - introducing thermal energy into the cooking chamber (14) of the cooking device (10); - determining the heat consumption of said thermal energy in said cooking chamber (14); as well as - setting the microwave power based on the microwave factor and the thermal energy consumption in the cooking chamber (14).

2. The method according to claim 1, wherein: The heat dissipation is characterized by heat dissipation power.

3. The method according to claim 2, wherein: The microwave power is set to a value corresponding to a product of the heat consumption power and the microwave factor.

4. A method according to any one of the preceding claims, wherein: The heat consumption is determined based on an average heating power of at least one heating device (18) of the cooking appliance (10) and / or based on a temperature change in the cooking chamber (14).

5. A method according to any one of the preceding claims, wherein: The heat consumption is determined based on the heating power introduced into the cooking chamber (14) and the power consumption of the cooking appliance (10).

6. The method according to claim 5, wherein: The power consumption is an experimentally determined value and / or a specified value which can in particular be obtained from a memory (32) of the cooking appliance (10).

7. The method according to claim 5 or 6, wherein: The power loss is a value that depends on the cooking chamber temperature.

8. A method according to any one of the preceding claims, wherein: An operating state of at least one fan impeller (26) of the cooking appliance (10) is taken into account when determining the heat consumption.

9. A method according to any one of the preceding claims, wherein: The microwave factor is specified by the appliance manufacturer for a particular cooking process or is suitable for being specified by the user and can in particular be adjusted by the user only to a small extent.

10. A cooking utensil, comprising: Cooking room (14); At least one microwave module (16) configured and arranged to feed electromagnetic radiation into the cooking chamber (14) for cooking a cooking product (12) introduced into the cooking chamber (14) by means of microwave energy; and a control and / or evaluation unit (30) configured and arranged to execute a computer program having program code means for executing the method according to any one of claims 1 to 9.

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