EP1800065B1 - Method for controlling a cooking process in a cooking device - Google Patents

Abstract

A method for controlling a cooking process in a cooking appliance includes determining, from a gas concentration detected during the cooking process, a set of function values corresponding to a shape of a function that depends on the gas concentration from a starting time t0 to a current time tn during a cooking process. Respective sets of comparison values for a comparison at the time tn are determined from the sets of reference values. A plurality of the sets of comparison values coming closest to the set of function values is automatically selected, and a set of parameters including at least an ending time of the cooking process is generated. The selected set of parameters is used for an electrical controller of the cooking appliance until a next comparison is made at a time tn+1. The method is automatically stopped as soon as the ending time of the cooking process has been reached.

Description

The invention relates to a method for controlling a cooking process in a cooking appliance.

For example, a generic method for controlling a cooking process in a cooking appliance from the EP 0 074 764 B1 known. The known method can be used for various food items. In order to close the cooking food currently being cooked, the output signal of a gas sensor arranged in the cooking chamber is evaluated at two different times at the beginning of the cooking process in an electrical control of the cooking appliance, wherein the type of food by means of the quotient formed from two sensor output signals is determined. The cooking process is terminated as soon as the sensor output signal has reached a value dependent on the type of food.

From the DE 103 00 465 A1 a method for controlling a cooking process in a cooking appliance is known. For this purpose, the cooking appliance, for example, a sensor designed as a humidity sensor, which is in signal transmission connection with an electrical control of the cooking appliance. The electrical control has a memory and an evaluation circuit, wherein in the memory a plurality of reference value quantities is stored, each of which parameter sets are assigned for the electrical control. In the known method, a value set is generated from the gas concentration detected during the cooking process in the evaluation circuit, which corresponds to the time profile of a function dependent on the gas concentration from the starting time t ₀ to a current time t _n during the cooking process. In the evaluation circuit, a comparison value set for the comparison at time t _n is respectively generated from the reference value sets, the plurality of comparison value sets being compared with the value set. The set of values that is closest to the value set is automatically selected by means of the evaluation circuit and the set of parameters assigned to this set of reference values is transformed to the time t _n via a calculation rule. In this way, the cooking process is controlled by means of the electrical control until the end of the cooking time.

From the EP 1 382 260 A2 Furthermore, a method is known in which a cooking device, in particular for baking, is controlled as a function of the output signal of a gas sensor. For this purpose, individual baking mixtures assigned reference value quantities of the gas sensor are stored in a memory of the device control. Via an input device selects the User of one of the stored baking mixes and thus a reference value set whose associated parameters are taken over by the controller for the cooking process. If, during the cooking process controlled in this way, deviations occur between the values detected by the gas sensor and the reference values, the baking process is changed or stopped.

The US 5,681,496 A discloses another method for controlling a cooking process using a humidity sensor. Similar to the one from the DE 103 00 465 A1 In this case too, the comparison between a measured set of values and a multiplicity of stored comparison value sets is carried out only once. The parameters determined above are determined for the further cooking process, which is regulated after the comparison, independently of the further development of the moisture in the cooking chamber.

Finally, out of the US 5,349,163 A a method for controlling a cooking process is known, in which a carbon dioxide sensor is used. Depending on how the concentration of carbon dioxide on the sensor changes during the cooking process, the further course of the cooking process is determined.

The invention thus raises the problem of providing a method for controlling a cooking process, which is also applicable to a variety of very similar in kind cooking goods with different cooking times.

According to the invention, this problem is solved by a method having the features of patent claim 1. Advantageous embodiments and expansions of the invention will become apparent from the following dependent claims.

The achievable with the present invention consist in particular in the provision of a method for controlling a cooking process, which is applicable to a variety of very similar cooking goods with different cooking times.

Although is out of the US 4,281,022 a method for controlling a cooking appliance is known in which the cooking time is determined by means of a comparison between one of the output signals of a arranged in a cooking moisture sensor value set and stored in a memory of an electrical control reference value quantity. Since the course of a current cooking process is influenced by the ambient conditions, provides the known method to estimate the cooking end time for the current cooking process by the above procedure. In contrast to the invention the known method is applicable only to a single type of cooking product, namely a thin piece of meat.

Furthermore, from the DE 196 09 116 A1 a method is known in which is determined for determining the Garendezeitpunkts determined during a current cooking process course of the core temperature in a larger piece of meat with stored in a memory of an electrical control temperature curves.

A particularly advantageous embodiment of the method according to the invention provides that in the comparison, the determination of the similarity of a comparison value set with the associated end time t _z to the set of values in dependence on the difference between the time t _n and the respective end time t _z . In this way, the quality in the selection of the most similar comparison value sets is improved since it is assumed that the farther the end time t _{Z of} the respective reference value set or reference value set from the current time t _{n is} removed, the comparison value set of the current set of values is increasingly dissimilar.

An advantageous development provides that at least the concentration of carbon dioxide is detected by the sensor and the value set generated in the evaluation circuit corresponds to the time course of the carbon dioxide concentration. Carbon dioxide is generated, for example, during each baking process.

Another advantageous development provides that at least the concentration of oxygen is detected by the sensor and the value set generated in the evaluation circuit corresponds to the time profile of the first derivative of the oxygen concentration after the time. The oxygen concentration is changed characteristically by the vapor during each cooking process.

A further advantageous embodiment provides that at least the concentration of an oxidizable gas is detected by the sensor. In this way, the use of low-cost semiconductor sensors is possible.

A particularly advantageous development of the teaching according to the invention provides that the sensor detects the concentrations of at least two different gases and each reference value quantity stored in the memory has in each case as many partial value quantities as gases have been detected. This further improves the quality of the results in the comparisons according to the invention. The selectivity between similar and not similar comparison value quantities in the comparison with the value set is increased because not only a single gas or its concentration is used for the comparison, but a plurality of gases or concentrations. The comparison is so multidimensional and includes as many partial comparisons as gases or gas concentrations are detected and are stored for the data in each reference value set.

In principle, the predetermined response of the electrical control to the comparison can be selected according to type and scope within wide suitable limits. Expediently, the residual cooking time is / are displayed on a display of the cooking appliance by means of the generated parameter set and / or the heating source for heating the cooking space is automatically switched off and / or an acoustic cooking signal is triggered.

A particularly advantageous embodiment of the teaching according to the invention provides that by means of the parameter set generated, the type of food in the current cooking process is determined and the operating mode and the cooking chamber temperature for the cooking process are selected and / or displayed. In this way, a largely automated cooking process is possible.

Another advantageous development provides that the output signal of the sensor in the evaluation circuit is processed only after expiry of a predetermined lead time after the start time t ₀ . As a result, the quality of the comparison is further improved because, after a lead time, the value set for the comparison is larger and therefore more meaningful.

In principle, it is possible that the set of values at any time t _n sets of comparison values generated with all of the stored sets of reference values are compared. Appropriately, in response to an input via an operating element of the cooking appliance or a pre-comparison carried out by means of the evaluation between the set of values and the plurality of comparison value sets at a predetermined time t ₁ , with t ₁ greater than t ₀ and less than t _n , for the comparison at time t _n preselected a subset of the plurality of comparison value sets.

Figur 1

eine Vorderansicht eines Gargeräts mit einem Garraum,

Figur 2

eine Seitenansicht des Gargeräts aus Fig. 1 in teilweise geschnittener Darstellung,

Figur 3

eine Seitenansicht eines anderen Gargeräts analog zu Fig. 2,

Figur 4

beispielhafte Gaskonzentrationen-Zeit-Verläufe zu einem Zeitpunkt t_n,

Figur 5

beispielhafte Gaskonzentrationen-Zeit-Verläufe zu einem Zeitpunkt t_n+1,

Figur 6

einen anderen beispielhaften Gaskonzentration-Zeit-Verlauf und einen Temperatur-Zeit-Verlauf,

Figur 7

weitere beispielhafte Gaskonzentrationen-Zeit-Verläufe, nicht normiert und

Figur 8

die Gaskonzentrationen-Zeit-Verläufe aus Fig. 7, zweifach normiert.

An embodiment of the invention is shown purely schematically in the drawings and will be described in more detail below. It shows

FIG. 1

a front view of a cooking appliance with a cooking chamber,

FIG. 2

2 a side view of the cooking appliance from FIG. 1 in a partially cutaway view,

FIG. 3

a side view of another cooking appliance analogous to FIG. 2,

FIG. 4

exemplary gas concentration-time profiles at a time t _n ,

FIG. 5

exemplary gas concentration time profiles at a time t _{n + 1} ,

FIG. 6

another exemplary gas concentration-time course and a temperature-time course,

FIG. 7

Further exemplary gas concentration-time profiles, not normalized and

FIG. 8

the gas concentration-time profiles of FIG. 7, twofold normalized.

In Fig. 1 a designed as an oven cooking device is shown. The cooking appliance has a cooking chamber 4 closable by a door 2 with a viewing window 6 and a control panel 8, wherein a display 10 and two control knobs 12 are arranged on the control panel 8.

Fig. 2 shows the cooking appliance of Fig. 1 in a partially sectioned side view. In the cooking chamber 4 designed as a carbon dioxide sensor sensor 14 is arranged for detecting the carbon dioxide concentration in the cooking chamber 4 and a rgutträger parked on a Ga 16 food inserted. Furthermore, the cooking appliance has an electrical control 18 which contains an evaluation circuit with a timer and a memory and is in signal transmission connection with the carbon dioxide sensor 14 and a heating source 20 designed as a resistance heating for heating the cooking chamber 4.

During operation of the cooking appliance, the vapor is discharged from the cooking chamber 4 in a manner known to those skilled in the art via a catalyst 22 and a vapor channel 24. This is symbolized in FIG. 2 by arrows 26. Thus, a current gas concentration is detected by the sensor 14, since the gases resulting from the cooking process are continuously removed from the cooking chamber 4. There is no concentration of these gases in the cooking chamber. 4

The inventive method is not limited to cooking appliances with catalyst 22, but the cooking appliance for carrying out the method according to the invention can be optionally equipped with or without catalyst 22, wherein the catalyst 22 is arranged on the specialist in known manner on or in the vapor channel 24.

As an alternative to the carbon dioxide concentration, other gas concentrations known to the person skilled in the art and suitable for the process according to the invention, such as, for example, the oxygen concentration, can also be used. If this is a cooking appliance with a catalytic converter 22, as already explained in the present exemplary embodiment, it is fundamentally advantageous to arrange the sensor 14, which is then designed as an oxygen sensor, in the flow direction downstream of the catalytic converter 22, since in this way it is connected to the evaluation circuit forwarded output signal of the sensor 14 is amplified. See Fig. 3. This is because the gas molecules escaping from the feed 16 and oxidizable by the action of the catalyst 22 oxidize, thus increasing the number of gas molecules displacing the oxygen after the catalyst 22. This oxygen is consumed. So if an oxygen sensor is used as a sensor 14, so is the Oxygen concentration is reduced to a greater extent than when installed in the flow direction before the catalyst.

If sensors 14 are used which detect gases which are produced during the cooking process and are emitted by the feed 16, their output signal is likewise amplified due to the increase in the number of gas molecules. As a result, on the one hand, the evaluation of the output signal of the sensor 14 and thus the control of the cooking process is further improved. On the other hand, it is possible to use a less sensitive and therefore less expensive sensor 14. The same applies to the use of a humidity sensor.

The above-described arrangement of the sensor 14 is not possible if with the sensor 14, the concentration of at least one oxidizable gas or, as in the present embodiment, to take place of carbon dioxide. In contrast, the arrangement of the sensor 14 in the flow direction in front of the catalyst 22 shown in FIG. 2 is possible in all gases suitable for the process according to the invention.

The method according to the invention is explained in more detail below with reference to the figures:

The food 16 is inserted into the cooking chamber 4 and the door 2 is closed. If the cooking process by means of one of the control knob 12 is started, that is, the heat source 20 is turned on, the course shown in Fig. 4 results.

FIG. 4 shows exemplary gas concentration-time profiles, the course of the gas concentration detected by the sensor 14 during the current cooking process being shown as a solid line a. The dashed lines b and c represent by way of example two reference value quantities stored in the memory. In fact, a multiplicity of reference value quantities are stored in the memory, each time curve of a reference function from a start time t ₀ to an end time t _{Z of} a reference cooking operation correspond and each of which parameter sets for the electrical control 18 are assigned. All curves a, b and c shown in FIG. 4 start at the start time t ₀ . The circular ring at the other end of the line a symbolizes the time t _{n of} the currently running cooking process. The square symbols at the other ends of the lines b and c symbolize the end time t _Z respectively stored in the memory. As clearly shown in FIG. 4, the reference value set b corresponds to a reference function with a short cooking duration, while the reference value set c corresponds to a reference function with a long cooking time. At the time t _n , the end time t _{Z of} the reference function represented by b has already expired.

As is apparent from Fig. 4, the carbon dioxide concentration increases in the cooking chamber 4 after the start time t _{0 of} the cooking process to a maximum value and then decreases until it reaches the current time t _n again. The time course of the carbon dioxide concentration of the currently running cooking process is detected in a manner known to those skilled in the art from the start time t ₀ to the time t _n and stored in the memory. The value set a generated in this way in the evaluation circuit of the electrical control 18 can not be directly compared with the stored reference value sets b and c at the time t _n , since the reference value sets, as already explained, at least partially correspond to reference functions whose end time t _{Z is} not coincides with the time of the current comparison t _n . Therefore, a comparison value set for the comparison at time t _{n is} generated from the reference value quantities b and c in the evaluation circuit before the comparison.

In order to compensate for the abovementioned differences in the transit time of the value set a to the individual reference value sets b and c, the values of the reference value sets of reference functions with an end time t _{Z become} smaller than t _n , that is, for example, from the reference value set b, by means of a calculation rule of t _{Z is} supplemented until the time t _n to allow in this way a comparison with the value set a. The calculation rule could be that the values of the reference value set b are set from the time t _Z to t _n equal to the values of the value set a in this time interval. An alternative to this is to set the values of the reference value set b equal to 0 in this time interval. A further alternative provides that the values of the reference value set b in this time interval is set equal to the product of a number between 0 and 1 and the maximum value of the reference value set b in the time interval t ₀ to t _Z. The last alternative thus represents a middle ground between the first and the second calculation rule. In this way, a corresponding comparison value set has been generated from the reference value set b, which can then be compared in the evaluation circuit with the value set a. The same applies to reference value sets of reference functions with an end time t _Z greater than t _n , that is, for example, from the reference value set c. Here, however, the value set a is supplemented by means of a calculation rule from t _n to the time t _Z instead of the reference value set c.

For reference value sets whose end time t _{Z is} identical to the instantaneous comparison time t _n , the reference value set does not necessarily have to be converted into a comparison value set. However, a fundamental transformation may still be useful, for example, to be able to perform the comparison at an earlier time during the current cooking process. This will be explained later in the text.

Subsequently, the value set a in the evaluation circuit is compared with the plurality of reference value quantities, for example b and c, associated comparison value quantities in a manner known to the person skilled in the art.

In the present embodiment now the three values of the quantity at time t _n similar sets of comparison values by means of the evaluation circuit automatically selected. In order to increase the quality of the comparison according to the invention, the similarity of a comparison value set with the associated end time t _Z to the set of values as a function of the difference between the time t _n and the end time t _{Z is} made. For example, it is possible that the distance between the end time t _Z and the current comparison time t _n itself is used for the comparison. Another possibility is to use the above-explained calculation rules for generating the comparison value quantities for this purpose.

In the example shown in FIG. 4, therefore, the reference value set b would be more similar to the set of values a than the reference value set c. Although both reference value quantities b and c in the initial phase of the current cooking process are approximately equal to the value set a, these differ very greatly by their end times t _Z. If one were now, as stated above, the distance between the respective end times t _Z and the current comparison time t _n using itself for the comparison, the reference values b of values a would be the current comparison time t _n similar in result than the reference values c.

In the example of FIG. 5, which shows the same reference value sets b and c, it would be exactly the opposite if the same criteria as in the example of FIG. 4 were used to determine the similarity of the respective reference value set b, c with the set of values a would. At the later time t _{n + 1} shown in FIG. 5, the value set a has advanced further, so that now the reference value set c is more similar to the set of values a than the reference value set b.

In this way, the three of the set of values a of the most similar comparison value sets are selected. These selected reference value sets are assigned corresponding reference value sets with parameter sets.

From these three parameter sets, a single set of parameters is generated via a predetermined calculation rule, which is used for the electrical control 18 until the next comparison at the time t _{n + 1} . The parameter set generated in this way contains at least the cooking end time for the currently running cooking process, which has been determined from the individual end times t _{Z of} the three parameter sets. This can be done, for example, by the formation of the arithmetic mean value from the end times t _{Z of} the selected reference value sets or reference value sets. Other mathematical methods known and suitable to the person skilled in the art are also conceivable.

As already explained, the method according to the invention is repeated continuously during the currently running cooking process. It is automatically ended as soon as a cooking end time determined by means of the evaluation circuit and as a function of the comparisons made has been reached during the cooking process currently taking place.

In principle, the parameter sets assigned to the individual reference value sets and thus the parameter set used for the control of the current cooking process can contain a multiplicity of suitable parameters. Expediently, the display of the remaining cooking time on the display 10 of the cooking appliance and / or the automatic switching off of the heating source 20 for heating the cooking chamber 4 and / or an acoustic cooking signal is triggered by means of the parameter set generated in the manner explained above.

A preferred embodiment of the method according to the invention provides that by means of the generated parameter set the type of feed 16 is determined in the instantaneous cooking process and the operating mode and the cooking space temperature are selected for the cooking process. For this purpose, it is necessary that the comparison according to the invention takes place already in the initial phase of the current cooking process. Up to this point in time, for example, an operating program of the cooking appliance identical for all dishes 16 or for individual groups of dishes 16 is used in order to produce a suitable set of values for the comparison.

Alternatively or in addition thereto, the output signal of the sensor 14 in the evaluation circuit is processed in the manner according to the invention only after a predetermined lead time has elapsed after the start time t ₀ . This ensures that disturbances of the output signal during an initial period after the start of the cooking process can not undesirably affect the processing of the output signal ssignals. For example, disturbances in the output signal can be caused by rapid heating, ie heating with the maximum heating power, or by switching on a circulating air fan, not shown. The result is local extreme values, ie local minimum and maximum values of the set of values. It can the Time duration for the lead time can be determined and determined for example by experiments. The lead time can be stored in the simplest case even in the memory. Alternatively, it is conceivable that the duration of the lead time is determined only during the current cooking process. For example, the end of the lead time can be determined as a function of the course of the gas concentration detected by the sensor 14. For this purpose, by means of the sensor 14 easily detectable changes in the course of the gas concentration, such as extreme values or turning points are suitable.

It should be noted that the terms extreme value and maximum or minimum value are not strictly mathematical. In the present invention, this is also to be understood as a plateau, that is to say when the gas concentration remains constant for a period at the highest or lowest value.

If instead of a sensor 14, which detects only a single gas, a sensor 14 is used, which detects a plurality of gases, it is possible, in an alternative embodiment to the present embodiment of the method according to the invention, this plurality of gases in the electrical control 18th evaluate and use for the comparison according to the invention. For this purpose, a plurality of respectively multidimensional reference value sets would thus be compared with a multidimensional set of values at the comparison time t _n in the manner explained above. In this case, the number of dimensions in the reference value quantities is identical to the number of dimensions in the value set and is equal to the number of gases detected by the sensor 14. Instead of dimensions one could also speak of subvaluations.

In experiments, it was found that the output signals of such a sensor 14 forwarded to the evaluation unit of the electrical control 18 are then particularly suitable for evaluation and thus for the comparison according to the invention, if the stored multidimensional reference value quantities and the value set of the currently running cooking operation depend on a previous one fixed and repetitive temperature profile have been generated at the sensor 14 or in its surroundings. Such a temperature profile is shown by way of example in FIG. 6.

The temperature cycle shown in Fig. 6 is repeated continuously during the entire duration of the current cooking process. The duration of a temperature cycle may be equal to the time interval between two consecutive comparison times t _n and t _{n + 1} . In the alternative embodiment discussed herein, the duration of a single temperature cycle is much shorter than the time interval between two successive comparison times t _n and t _{n + 1} . For reasons of clarity, only a single temperature cycle d with the concentration curve e associated with it was shown in FIG. During the temperature cycle d, measured values are recorded with the sensor 14 at mutually different times. In this case, the concentrations of mutually different gases are detected by the sensor 14 in at least two different time points in the present embodiment. In this way, an artificial curve, which is shown by way of example in FIG. 6, results. The values of the curve e correspond to the concentrations of at least two different gases detected with the sensor 14 during the temperature cycle d. If, for example, four different gases were detected by the sensor 14, the concentration of each of the four gases would be detected by the sensor 14 alternately at the times of the measured value recording. From the individual values recorded in this way, a time profile would then be generated in the electrical control 18 in a manner known to the person skilled in the art. The further processing is as already explained. The number of dimensions or partial value quantities of the value set generated thereby and the stored reference value quantities would be four in this case.

In the case of a very large number of reference value quantities, it may make sense that, depending on an input via the operating elements 12 of the cooking device or a pre-comparison carried out by means of the evaluation circuit, between the value set and the multiplicity of comparison value sets at a predetermined time t ₁ , with t _{1 being} greater as t ₀ and smaller than t _n , a subset of the plurality of comparison value sets is preselected for the comparison at time t _n . This pre-selection can be effected, for example, by preselecting those whose maximum value or their first maximum value fall within a predetermined time interval by the time of the maximum value or of the first maximum value of the value set from the total quantity of reference value sets or comparison value sets.

A supplementary or alternative possibility of reducing the amount of data to be processed in the electric control 18 in the case of a large number of reference value sets is to normalize the value set before the comparison and compare it later with likewise standardized reference value sets. Basically, it is possible to simply normalize the set of values and the stored reference value sets. Conveniently, this is a two-fold normalization used, which is explained in more detail with reference to FIGS. 7 and 8.

FIG. 7 shows by way of example a set of values f and a stored reference value quantity g generated from the detected carbon dioxide concentration during a current cooking process. The two curves are not normalized and each have a maximum value, f _max and g _max , on.

FIG. 8 shows the set of values f and the reference value set g from FIG. 7 in a two-standard representation, wherein in this example the maximum value of the set of values f _max and the time t _{max associated} with this maximum value have been set to 1. For courses with several local maximum values, it is also possible to normalize to the temporally first maximum value and the time allocated to it. Other standardizations known to the person skilled in the art are also conceivable.

A further advantageous development of the aforementioned embodiment provides that, in each case, a derivative according to time, for example the first derivative with respect to time, is generated from the curves of FIG. 7 before their normalization. This allows extremes and inflection points to be used for normalization to be generated at an even earlier point in time during the current cooking process. Thus, the evaluation in the electrical control 18 can be started earlier, as a result of which information from the cooking appliance to the user can be generated early on in an already explained manner.

However, the teaching of the invention is not limited to the present embodiment. For example, the plurality of most similar comparison value sets are freely selectable within appropriate limits and are not limited to a number of three. Furthermore, other computation instructions known to the person skilled in the art for generating the comparative value sets and for carrying out the comparison as well as generating the parameter set used for the controller 18 until the respective next comparison are conceivable. In addition, the type of sensor 14 and the gas types detectable with it can be selected within wide suitable limits. For example, the evaluation of the oxygen concentration or the concentration of individual oxidizable gases is possible. Furthermore, the method according to the invention is not restricted to a selection of recipes, operating modes or cooking chamber temperatures.

Claims (10)

1. Method of controlling a cooking process for a cooking device with a cooking chamber (4), at least one sensor (14) for detecting a gas concentration in the cooking chamber (4) and an electric control means (18), which includes a recognition circuit with a timing element and a storage means and is connected to the sensor (14) so as to transfer signals, wherein a plurality of reference value quantities are stored in the storage means, the said reference value quantities each corresponding to the time development of a reference function from a start time point t₀ to a respective end time point t_z of a cooking process and in each case parameter sets for the electric control means (18) being associated with the said reference value quantities , characterised in that the method includes the following method steps:

   - from the gas concentration detected during the cooking process a value quantity is created in the recognition circuit, the said value quantity corresponding to the time development of a function dependent on the gas concentration from the start time point t₀ to a current time point t_n during the cooking process,

   - in each case a comparative value quantity is created in the recognition circuit from the reference value quantities for the comparison at the time point t_n,

   - the value quantity is compared in the recognition circuit with the plurality of comparative value quantities,

   - a plurality of comparative value quantities nearest the value quantity is automatically selected by means of the recognition circuit and, via a calculation specification, the parameter set, which is used for the electric control means (18) up to the next comparison at the time point t_n+1 and contains at least the cooking end time point for the currently elapsing cooking process, is created from the associated parameter sets and

   - the method is automatically terminated as soon as a cooking end time point, determined by means of the recognition circuit in dependence on the comparisons carried out, has been reached.
2. Method according to claim 1, characterised in that during the comparison, the determining of the likeness of a comparative value quantity with the associated end time point t_z to the value quantity is effected in dependence on the difference between the time point t_n and the respective end time point t_z.
3. Method according to one of claims 1 or 2, characterised in that at least the concentration of carbon dioxide is detected by the sensor (14) and the value quantity created in the recognition circuit corresponds to the time development of the carbon dioxide concentration.
4. Method according to one of claims 1 or 2, characterised in that at least the concentration of oxygen is detected by the sensor (14) and the value quantity created in the recognition circuit corresponds to the time development of the first removal of the oxygen concentration with respect to time.
5. Method according to one of claims 1 or 2, characterised in that at least the concentration of an oxidizable gas is detected by the sensor (14).
6. Method according to at least one of claims 3 to 5, characterised in that the sensor (14) detects the concentrations of at least two gases that are different from each other and each reference value quantity stored in the storage means in each case has just as many part value quantities as gases that have been detected.
7. Method according to at least one of claims 1 to 6, characterised in that through the intermediary of the parameter set created, the display of the remaining cooking time is triggered on a display (10) of the cooking device and/or the automatic switching-off of a heat source (20) that is heating the cooking chamber (4) is triggered and/or an acoustic cooking end signal is triggered.
8. Method according to at least one of claims 1 to 7, characterised in that through the intermediary of the parameter set created, the type of meal in the current cooking process is determined, and the type of operation and the temperature of the cooking chamber for the cooking process is/are selected and/or is/are displayed.
9. Method according to at least one of claims 1 to 8, characterised in that the output signal of the sensor (14) is not processed in the recognition circuit until a previously established delay time after the start time point to has elapsed.
10. Method according to at least one of claims 1 to 9, characterised in that in dependence on an input made via a control element (12) of the cooking device or on a preliminary comparison carried out through the intermediary of the recognition circuit between the value quantity and the plurality of comparative value quantities at a previously established time point t₁, where t₁ is greater than t₀ and smaller than t_n, a part quantity is preliminarily selected for the comparison at the time point t_n from the plurality of comparative value quantities.

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