DE102010037284A1 - Method for carrying out a cooking process - Google Patents

Abstract

The present invention relates to a method for carrying out a cooking process in at least one cooking chamber of a cooking device with at least temporary circulation of the cooking chamber atmosphere by means of a circulating device, wherein at least one first fan wheel of the circulating device is driven about a first axis of rotation during at least one cooking process step in such a way that at least one first change of direction of rotation from a first state of rotation, in which the first fan wheel is rotated in a first direction of rotation, to a second state of rotation, in which the first fan wheel is rotated in a direction of rotation opposite to the first, and then a second change of direction of rotation from the second state of rotation be carried out in the first rotational state, the duration of a cycle comprising at least two first changes in direction of rotation, between which a second change in direction of rotation is carried out, as a function of at least one egg a first parameter of the cooking process is set, this cycle duration being selected to be longer than a predetermined first minimum cycle duration of more than zero seconds and shorter than a predetermined first maximum cycle duration, and the first minimum cycle duration and the first maximum cycle duration are predetermined independently of the first parameter.

Description

The present invention relates to a method for carrying out a cooking process in at least one cooking chamber of a cooking appliance under at least temporary circulation of the cooking chamber by means of a circulating device, wherein at least one first impeller of the circulating device is driven about a first axis of rotation during at least one cooking process step of the cooking process such that at least one first rotational direction change from a first rotational state in which the first fan is rotated in a first rotational direction, in a second rotational state in which the first fan in a first rotational direction opposite, second rotational direction is rotated, and then a second rotational direction change from the second rotational state be carried out in the first rotational state.

Various methods for carrying out a cooking process in which an atmosphere is circulated through a cooking chamber are known from the prior art. For example, the US 6,346,691 B2 a method for controlling a convection fan of a microwave oven. It is provided that for the entire cooking process, a direction of rotation of the convection fan is set in dependence on a selection of Gargutart, in particular a flow direction of an atmosphere is determined by a cooking chamber depending on Gargutart. The disadvantage here, however, is that it can lead to uneven temperature distributions in the cooking chamber when performing a cooking process.

To overcome this disadvantage proposes, for example, the WO 84/01266 A1 a method and an oven for treating products with a heated air flow. In the oven two fan wheels are provided which are each driven alternately in opposite directions. To be able to reverse a flow of a cooking chamber atmosphere through the cooking chamber during a cooking process, one of the two fans is operated alternately, with a reversal of the flow direction by switching between the fans with a fixed frequency.

Similarly, the DE 24 03 294 C2 a furnace for heat treatment of food, in which a mutual switching on and off of two counter-rotating rotors is performed, wherein in a temporal overlap area both rotors are driven, while in the remaining period of one of the rotors is mechanically decoupled from a drive means. Again, the switching takes place at a predetermined frequency.

In addition, the reveals DE 30 31 041 C2 a gas or electrically heated circulating air oven, in which two impellers are provided. The directions of rotation are changed periodically and the impellers are periodically reciprocally operated but at a fixed frequency.

In addition, the reveals US 2003/0000515 A1 a convection oven having different air flow patterns. For this purpose, two fans are provided, wherein it is proposed that both a fan speed and a fan rotation direction be changed periodically or at any random frequency. A disadvantage of this method, however, is that still no adequate adjustment of the flow of the cooking chamber through the cooking chamber for producing a uniform temperature distribution within the oven while optimally adapting to the various parameters of the cooking process is possible.

For this the beats US 4,467,777 a gas or electrically heated convection oven for baking food. In this cooking appliance, two fan wheels are provided, with a periodic reversal of direction of rotation of the fan wheels takes place, in a first alternative with a predetermined frequency, for example, two minutes, and in a second alternative with a manually adjustable or one of a cooking space temperature dependent Frequency.

Finally, the reveals DE 103 16 503 B3 a generic method. The DE 103 16 503 B3 relates to an oven and a method for operating a baking oven, which has a baking chamber in which the baked goods to be baked can be received, and with at least two fans for circulating the air in the baking chamber. During the baking process, a synchronizing phase is provided between the fans, during which the fans are driven in the same direction circumferentially, while in addition at least one mating phase is provided, in which the fans are driven in opposite directions, wherein in addition still the direction of the respective fans is reversed. It is proposed that the respective phase length be determined by dividing the total duration of the cooking process by a multiple of four. Furthermore, the synchronous and countercurrent phases may have different lengths.

A disadvantage of this generic method, however, is that at least two fans must be used for equalization and, although the uniformity based on a Gar result and a browning is positively influenced by a reversal of Lufterrädern, but sufficient adjustment of the cycle times of the change of direction to the different cooking operations is possible and so an optimally cooked and browned food is not always obtained. In particular, too low cooking times due to the high alternating frequency overuse, z. As overheating, a drive device of the circulation device arise. Due to the heat radiation, an increased alternating frequency also leads to heating in the region of a space in which a drive unit of the circulation device is arranged, as a result of which a temperature gradient is generated in the adjacent cooking space. Also, the increased alternating frequency leads to an increase in energy consumption, which is generally undesirable. On the other hand, too long cooking times can lead to the formation of temperature gradients in the cooking chamber and thus to a deterioration of the cooking result, in particular with regard to uniformity in the case of large items to be cooked and / or a plurality of simultaneously due to the resulting comparatively long cycle or phase lengths Food, come.

It is therefore an object of the present invention to further develop the generic method such that the disadvantages of the prior art are overcome, in particular the cycle times of changes of direction of a circulation device are adapted to different cooking courses, so as to provide an optimally uniformly cooked and browned food for each cooking process receive.

This object is achieved in that the duration of a cycle comprising at least two first direction of rotation between which a second change of rotation is performed, is set in response to at least a first parameter of the cooking process, said cycle longer than a predetermined first minimum cycle time of more is selected as zero seconds and shorter than a predetermined first maximum cycle duration, and the first minimum cycle duration and the first maximum cycle duration are set independently of the first parameter.

It may be provided in particular that at least a second fan of the circulating means is at least temporarily rotated about a, in particular substantially parallel to the first axis of rotation extending second axis of rotation during the cooking process, wherein at least a third rotational direction change of a third rotational state in which the second Fan is rotated in a third rotational direction, which corresponds in particular to the first rotational direction is rotated in a fourth rotational state in which the second fan in a third rotational direction opposite, fourth rotational direction, which corresponds in particular to the second rotational direction, and a fourth direction of rotation from the fourth rotation state to the third rotation state.

It is also proposed with the invention that during at least a first cooking process step the first impeller and / or the second impeller is not reversed, wherein the first cooking process preferably a preheat, a cooling, a load detection and / or a holding phase, in the preferably no food is arranged in the cooking chamber, comprises and / or during at least a second Garprozessschrittes, which includes in particular a Beschwadung, the direction of rotation of the first fan and / or the second fan is not changed and maintained for the duration of the second Garprozesschrittes.

In the aforementioned embodiments, it is particularly preferred that a recirculation state is defined in each case by a single rotational state or a combination of at least two different rotational states, and that the recirculation conditions are repeated periodically.

In the method, it may be provided that the first rotation state is maintained for a first time period, the second rotation state is maintained for a second time period, the third rotation state is maintained for a third time period, and the fourth rotation state is maintained for a fourth time period in that the cycle duration corresponds at least to the sum of the first time span and the second time span, optionally additionally to the sum of the third time span and the fourth time span.

In the aforementioned embodiment, it is preferred that the first period of time and the second time period and / or the first time period and the second time period, in particular for setting different long Umwälzzustände, different lengths and / or can be selected in dependence on a second parameter of the cooking process, wherein preferably the first time period and the second time period is greater than a first predetermined and deviating from zero seconds first minimum value, for example 1 minute or 2 minutes, and less than a predetermined first maximum value, for example 2 minutes or 4 minutes, and / or preferably the third Period of time and the fourth period of time greater than a predetermined and deviating from zero seconds second minimum value, for example, 1 minute, and less than a predetermined second maximum value, for example, 2 minutes are set, in particular the first minimum value, the first maximum value, the second minimum value and / or the second maximum value is / are predetermined independently of the first parameter and / or the second parameter, and / or in particular the second minimum value equal to the first minimum value and / or the second maximum value is set equal to the first maximum value, and / or in particular the minimum cycle duration is twice the first minimum value and / or twice the second minimum value, for example 4 minutes, and / or the maximum cycle duration is twice the first maximum value and / or twice the second maximum value, for example 8 minutes, corresponds or correspond.

A method according to the invention can also be characterized in that the cycle comprises at least a third rotation direction change and a fourth rotation direction change, preferably two third rotation direction changes are included.

It is also proposed with the invention that the third change of direction ( 9 ) is delayed by a first time offset to the second direction of rotation change and / or the fourth direction of rotation change by a second time offset is performed to the first rotation direction change, and the first time offset and / or the second time offset determined in dependence on a third parameter of the cooking process will or will be.

It is preferred that the first time offset (t ₃ -t ₂ ) deviate from the half of the first time span (Δt ₁ ) and / or the second time offset (t ₁ ) deviates from the half of the second time span (Δt ₂ ). for setting different long Umwälzzustände, wherein preferably the third parameter is representative of an asymmetry of a loading of the cooking chamber with food to be cooked.

An alternative to the aforementioned embodiment provides that the first time offset is equal to the second time offset, the first time offset is equal to half of the first period of time, and / or the second time offset is equal to half of the second period of time to set equally long recirculation conditions.

Also, a method according to the invention may be characterized in that a plurality of second fan wheels is used, wherein two third rotational direction changes of two second fan wheels delayed by a third time offset to each other and / or two fourth direction of rotation of two second fan wheels delayed by a fourth time offset performed wherein preferably the third time offset corresponds to the first time offset and / or the fourth time offset and / or the fourth time offset corresponds to the second time offset, and / or preferably the third time offset and / or the fourth time offset depending on at least a fourth parameter of the cooking process , which preferably corresponds to the third parameter, is set or be.

It is also proposed that the third time offset is selected equal to half of the third time period and / or the fourth time offset is selected equal to half of the fourth time period for setting equally long Umwälzzustände, or, in particular depending on the asymmetry of a load of the cooking chamber with fourth food parameter representative of the food, the third time offset from the half of the third period of time and / or the fourth time offset deviates from the half of the second period or deviate to set different periods Umwälzzustände.

• • zumindest ein Garparameter, insbesondere eine Dauer des Garprozesses, eine Dauer des Garprozessschrittes, eine Restdauer des Garprozesses, eine Restdauer des Garprozessschrittes, eine Temperatur, eine Garraumtemperatur, eine Umgebungstemperatur des Gargerätes, eine Feuchte, eine Garraumfeuchte und/oder eine Umgebungsfeuchte des Gargerätes, ein Beladungsgrad, eine Beladungsverteilung in dem Garraum, eine Dichte einer Umgebungsatmosphäre, eine geodätische Höhe eines Aufstellungsortes des Gargerätes und/oder eine Öffnungszeit einer Garraumtür, und/oder
• • zumindest ein Gargutparameter, insbesondere eine Gargutart, eine Gargutgröße, ein Gargutausgangszustand, eine Garguttemperatur, ein Garegrad und/oder ein Hygienegrad, und/oder
• • ein Soll-Wert des Garparameters und/oder Gargutparameters, ein Ist-Wert des Garparameters und/oder Gargutparameters und/oder ein Differenz-Wert zwischen dem Soll-Wert und dem Ist-Wert

ausgewählt wird.A method according to the invention can also be characterized as the first parameter, the second parameter, the third parameter and / or the fourth parameter of the cooking process

• At least one cooking parameter, in particular a duration of the cooking process, a duration of the cooking process step, a remaining time of the cooking process, a remaining time of the cooking process step, a temperature, a cooking chamber temperature, an ambient temperature of the cooking appliance, a humidity, a cooking space moisture and / or an ambient humidity of the cooking appliance, a degree of loading, a loading distribution in the cooking chamber, a density of an ambient atmosphere, a geodetic height of a place of installation of the cooking appliance and / or an opening time of a cooking chamber door, and / or
• At least one cooking product parameter, in particular a type of cooking product, a size of the product to be cooked, a starting state of the cooking product, a temperature of the product, a degree of cooking and / or a degree of hygiene, and / or
• A setpoint value of the cooking parameter and / or cooking product parameter, an actual value of the cooking parameter and / or the cooking product parameter and / or a difference value between the setpoint value and the actual value

is selected.

It is particularly preferred that the minimum cycle duration, the maximum cycle duration, the first minimum value, the second minimum value, the first maximum value and / or the second maximum value depend on the presence and / or the number of second fan wheels, an operating parameter and / or a characteristic of the cooking appliance and / or the circulation device, preferably an energy intake, a heat release, an electrical resistance, an impedance, an ohmic resistance, a sound level and / or a period of time for the first direction of rotation change, second direction of rotation change, third direction of rotation change and / or fourth change of direction, is given or will be.

It is also proposed that an operating parameter and / or a parameter of a drive unit of the first fan wheel and / or the second fan wheel is selected and / or the operating parameters and / or the characteristic during a first rotation direction change, second rotation direction change, third rotation direction change and / or fourth Direction of rotation change is determined.

Furthermore, the invention proposes that the cycle duration is selected equal to the minimum cycle duration if the total duration of the cooking process and / or the cooking process step falls below a predetermined minimum duration, and / or the cycle duration is selected equal to the maximum cycle duration, if the total duration of the cooking process and / or the Cooking process step exceeds a predetermined maximum duration.

A method according to the invention can also be characterized in that the cycle duration, the first time span, the second time span, the third time span and / or the fourth time span are / is set such that a predetermined value is set during the entire cooking process and / or the entire cooking process step Number of cycles is passed if the duration of the cooking process and / or the cooking process step, a period greater than the predetermined number of cycles multiplied by the minimum cycle duration and less than the predetermined number of cycles multiplied by the maximum cycle duration is specified.

It is also proposed that the cycle duration, the first time span, the second time span, the third time span and / or the fourth time span be reduced, in particular the cycle duration equal to the minimum cycle duration and / or the first time span and / or the second time span the first minimum value and / or the third time period and / or the fourth time period is set equal to the second minimum value when the first parameter, the second parameter, the third parameter and / or the fourth parameter during the cooking process and / or the Garprozesschrittes is changed , the difference value of the temperature exceeds a first threshold value, the setpoint value of the temperature exceeds a second threshold value and / or the duration of the cooking process and / or the cooking process step is shortened.

In an alternative to this, it is proposed that the cycle duration, the first time span, the second time span, the third time span and / or the fourth time span be increased, in particular the cycle duration equal to the maximum cycle duration and / or the first time span and / or the second time span the first maximum value and / or the third time period and / or the fourth time period is set equal to the second maximum value when the first parameter, the second parameter, the third parameter and / or the fourth parameter during the execution of the cooking process and / or the Garprozesschrittes is changed because the difference value of the temperature falls below a third threshold, the target value of the temperature falls below a fourth threshold and / or the duration of the cooking process and / or the cooking process step is extended.

Finally, it can be provided that the rotational speed of the first fan wheel and / or the second fan wheel is changed in dependence on the first parameter, the second parameter, the third parameter and / or the fourth parameter.

The invention is therefore based on the surprising finding that by determining a minimum cycle duration and a maximum cycle duration for a cycle in which all Umwälzzuständen a circulation device are passed through, so for a uniform food treatment, especially cooking, all necessary directions of rotation of the or the fan wheels of the circulating device are, regardless of the specific circumstances and requirements for a cooking process or a Garprozessschritt, can ensure that overuse of a drive unit of the fan is avoided and at the same time the best possible homogenization of the cooking atmosphere to achieve optimum cooking results for all cooking processes can be ensured. Although the predetermination of the minimum cycle duration and the maximum cycle duration takes place independently of the respective cooking process to be carried out, it preferably depends on parameters and / or operating parameters of the cooking appliance, preferably the circulation device, in particular a drive unit. Suitable for this purpose are, for example, an energy consumption, resistance, degree of heating, degree of wear or noise level of the circulation device, for example in the case of a change of direction, ie a reversal of a direction of rotation of a fan wheel of the circulation device. With comparatively long cooking processes or cooking process steps, a cycle duration of the cycle and thus the respective duration of rotation of a fan in a first direction of rotation is only extended up to a predetermined value, while longer cooking processes a number of cycles and thus the changes of direction or reversals, at more consistent maximum duration of the cycles and time periods for rotations in the respective directions of rotation is increased.

It is thus achieved that during the maximum cycle time a sequence of recirculation conditions, in particular all possible recirculation conditions, are traversed, ie during each cycle for the desired cooking result a best possible cooking chamber atmosphere is provided and this due to the increasing during longer cooking cycles number of cycles over the entire Length of the cooking process. On the other hand, the limitation of the cycle time to the minimum cycle time ensures that, with comparatively short cooking times, a maximum number of circulation states is passed through in order to provide the best possible cooking chamber atmosphere, but at the same time avoid overstress which can lead to premature wear.

Thus, the method according to the invention makes it possible to achieve the best possible equalization of the cooking chamber atmosphere even by using a single fan wheel, and thus a uniformity with respect to a cooking result, in particular a browning, can be achieved.

In accordance with a preferred embodiment of the method according to the invention, an adaptation of the respective time periods for rotation in a corresponding direction of rotation for each cooking process step is determined independently of the other cooking process steps and thus an optimum cooking chamber atmosphere is provided for each individual cooking process step.

According to the invention, a minimum or maximum cycle duration, for example four minutes or eight minutes, is specified. In this case, a cycle duration describes the time span in which the respective circulation states of the circulation device are traversed, in particular two changes of direction of rotation take place. Thus, this minimum cycle duration can be, for example, 4 minutes and the maximum cycle duration 8 minutes.

In the case of the use of a single impeller two Umwälzzustände, namely a left-hand rotation and clockwise for the respective period before, while at a larger number of fan wheels, for example, two fan wheels, a total of at least four Umwälzzustände may be present, namely a left-hand rotation and a clockwise, at which the fan wheels are rotated in the same direction, in particular synchronously, and a left-right run or right-left run, that is, that the fan wheels are rotated in opposite directions. In the case of a single fan wheel, therefore, a cycle initially comprises a first change in direction of rotation from a first rotation state into a second rotation state and then a second rotation direction change from the second into the first rotation state and is concluded with a renewed first rotation direction change or begins again with this first first rotation direction change new cycle.

By changing the cycle times thus results in a change in the time span for a rotation of the respective fan in one of the respective directions of rotation. By specifying the minimum cycle duration and the maximum cycle time, the number of fan impellers and the resulting number of recirculation states result in respective minimum values and maximum values for the time periods. In this case, the minimum values and maximum values are dimensioned such that a sufficiently long discharge of the circulation device takes place during this time, for example, this can cool sufficiently, so that there is no overburden, for example a further heating, in a subsequent change of direction. In the case of short cooking times, ie cooking processes or cooking process steps with a short duration, for example a duration of one second to, for example, 32 minutes, the fan wheel is reversed based on the minimum cycle duration or the minimum value for the time span. A minimum duration for the cooking process or the cooking process step is thus for example 32 minutes.

If the cooking time, ie the duration of the cooking process and / or the duration of the cooking process step longer, followed by a dynamic adjustment by the number of cycles is indeed maintained, the cooking time or the duration of the cooking process step but divided by the number of cycles and thus the cycle time and from it the respective periods are or will be determined. However, if a maximum duration of the cooking time or the duration for the cooking process and / or the cooking process step is reached, the maximum cycle time is reversed or the time span for the rotation in the respective rotation direction is set to the maximum value. The maximum duration is thus for example 64 minutes.

Since it is important for the uniformity of the cooking atmosphere that the respective reversing cycle is completed as completely as possible during a cooking process and / or a cooking process step, the aim is always that the minimum cycle time or the minimum value is as low as possible, so that all circulation conditions are passed through even with short cooking times become. As a parameter of the cooking process for setting the cycle time or periods, for example, the duration of the cooking process or the cooking process step is used.

Too short cycle times or periods, however, it could lead to an overload of a Drive unit come, so that by the minimum cycle duration overloading of the drive unit, in particular as a function of a drive power, could occur. The minimum cycle duration or the respective minimum value is therefore selected to be correspondingly large in order to avoid this overuse.

For long cooking times or for a long duration of a cooking process step, the different phases of cooking are run through on the other side, so that the cycle time can be limited to a maximum and also all states during a phase, especially a tanning phase, are run through.

According to the invention, the adjustment of the cycle duration or the respective time periods is carried out both when carrying out a manual cooking process or cooking process, as well as a programmed cooking process. Thus, the cooking process step in a manual cooking, the entire cooking process, which is determined only by the specification of a temperature and a cooking time include, while in a programmed cooking, an adjustment of the cycle time or the respective time periods in the individual cooking process steps, substantially independent of a Gesamtgardauer or Gesamtgarprozessdauer is performed.

This also makes it possible for the reversing behavior to be adapted to the special requirements in the case of automatic or programmed cooking processes.

Thus, in certain first cooking process steps reversing completely be dispensed with, for example, in an empty cooking chamber, which is also referred to as steady state, in which state also a rotational speed of the fan wheels can be reduced in a preheating, with this a fixed direction of rotation can be specified, a cooling of the cooking appliance, which in this also a direction of rotation of the fan wheels can be specified, as well as a load detection, in which also a predetermined direction of rotation of the fan wheels can be prescribed.

It is also particularly preferred that during a second cooking process step, such as steaming, that is to say spraying of a heating device, which is arranged in particular in the region of the fan wheel, a fan wheel is likewise driven in a predetermined direction of rotation and without reversing. It should be noted that for the purposes of the invention, a designation with the adjectives "first" and "second" no, especially temporal, sequence defined, but only for distinctive designation, for example, different Garprozessschritte used.

A further adaptation of the cycle duration or time periods can be achieved by adjusting the cycle duration or the time span as a function of a cooking chamber temperature, ie using a cooking parameter such as a temperature as parameter of the cooking process for setting the time periods. It can thus be provided that in the case of a strong increase in a desired cooking chamber temperature, for example in the case where a desired value of the cooking parameter, for example the setpoint temperature, is at least 50 Kelvin above an actual value of the cooking parameter, for example an actual cooking temperature. Temperature is, ie exceeds a first threshold value or when exceeding a second threshold for a desired cooking space temperature, for example 120 ° C, reversing is performed with high frequency, in particular the cycle time to the minimum cycle time or the time periods are reduced to the minimum values.

In contrast, in the case of a strong drop below the setpoint temperature by an actual temperature, for example by a third threshold value, and / or in a strong reduction of the set cooking space temperature, for example, when falling below a fourth threshold, a cycle duration can be increased, for example except for the maximum cycle time. An adaptation of the cycle duration or time periods in the range between the minimum value and the maximum value or the minimum cycle duration and the maximum cycle duration can also take place if during the execution of the cooking process an adaptation of the duration of the cooking process or of the cooking process step is lengthened or shortened, in particular by to achieve the desired number of cycles during the cooking process and / or cooking process step.

Furthermore, the invention provides that in the case in which a door of the cooking chamber is opened during the execution of a cooking process step, whereby the fan wheel is stopped, is detected after closing the door, if the remaining time for rotation in the respective direction of rotation, So the rest of the time, sufficient to start the fan again, or if the fan is rotated directly in the opposite direction.

According to the invention, a further adaptation can take place in that the time intervals for opposite directions of rotation are chosen to be different or the time offsets between changes in direction of rotation of different fan wheels are chosen such that one direction of rotation of one fan wheel does not occur after one half of the time span for a rotation of another fan wheel Time offenses for the different direction of rotation change are chosen to be different lengths. This ensures that the Umwälzzustände be different lengths, for example, to compensate for a non-uniform, in particular asymmetric loading of the cooking chamber.

In summary, it is thus achieved by the invention that the best possible uniformity, in particular based on a browning or a degree of cooking, even with different cooking processes and ambient and cooking conditions is achieved because at long cooking a rare reversing the fan wheels is made and beyond a conservation a drive unit is achieved.

Further advantages and features of the invention will become apparent from the following description, are explained in the preferred embodiments of the invention by way of examples.

Showing:

1 a graphical application of a rotational speed over the time of rotational movements of a circulation device of a cooking appliance according to the invention with two fan wheels;

2 a graphical plot of a rotational speed over time of rotational movements of a circulating means with a fan for different cooking times;

3 a plot of a rotational speed over time of rotational movements of a circulating device with two fan wheels with a change in temperature;

4 a graphical representation of a rotational speed over time of rotational movements of a circulating device with a fan in detail for different cooking process steps; and

5 a graphical application of a rotational speed over the time of a rotational movement of a circulating device with a fan at a change in duration during a cooking process.

In 1 the rotational speeds v _{d of} a circulation device in accordance with the method according to the invention are shown graphically over time t, the circulation device comprising two fan wheels. In 1 shows a first graph shown in a solid line 1 the rotational speed of a first fan while a graph shown with a broken line 3 represents the rotational speed of the second fan wheel.

As it turned out 1 results, at a time t ₀ = 0 sec. a first change of direction 5 of the first fan wheel is performed from a first direction of rotation in a second direction of rotation and in a period t ₀ to t ₁ in a first circulating state z _{1 of} the circulating device, the first fan and the second fan wheel are rotated in the same direction. At a time t ₁ , the direction of rotation of the second fan wheel is reversed, so that a second circulating state z _{2 is} established, in which the fan wheels are rotated in opposite directions. At a time t ₂ is replaced by a second change of direction 7 reverses the direction of rotation of the first fan from the second direction of rotation in the first direction of rotation, so that a third Umwälzzustand z ₃ sets by this, to the first circulation condition z ₁ and the second Umwälzzustand z ₂ different combination of rotational states of the air wheels, said third Umwälzzustand z ₃ is characterized in that the fan wheels are rotated in the same direction, but in an opposite direction in comparison to the state z. ₁ At time t _{3, there} is a renewed reversal of the direction of rotation for the second fan wheel, which is the third change of direction of rotation 9 is designated, so that due to this combination of other rotational states, a circulating state z ₄ sets, in which the fan wheels are rotated in opposite directions, but with opposite direction of rotation in comparison to the Umwälzzustand z ₂ . The time period t ₂ to t ₄ identifies a first period Δt ₁ and the period t ₄ to t ₆ , which corresponds to the period t ₀ to t ₁ , a second period Δt ₂ , In addition, the period t ₁ to t _{3 determines} a third Period of time .DELTA.t ₃ , while the addition of the time periods t ₃ to t ₄ and t ₀ to t ₁ and a period t ₃ to t _5, a fourth time period .DELTA.t ₄ represent. At time t ₄ , a renewed first change of direction occurs 5 ' , during the change of direction 9 at time t ₃ as the third and at time t ₁ as a fourth change of direction 11 referred to as.

In the in 1 shown operating state, the first time period .DELTA.t ₁ , second time period .DELTA.t ₂ , third time period .DELTA.t ₃ and fourth time period .DELTA.t _{4 are the} same length and correspond to a minimum value, in this example two minutes. It follows that a total cycle time, that is, a passage through the states z ₁ , z ₂ , z ₃ and z _{4 takes} a total of four minutes. In this cycle, the sequence of Umwälzzustände z ₁ , z ₂ , z ₃ and z _{4 is} run through. This duration also represents the minimum cycle duration.

After passing through this first cycle is by another first change of direction 5 ' at time t _4, a new cycle is started, so that at time t _5, the second fan by a fourth change of rotation again 11 ' is reversed, at time t _6, the first fan by a second change of direction again 7 ' and at time t ₇ , the second fan again by a third change of direction 9 ' is reserved. During a cycle, therefore, a reversal of the direction of rotation takes place in both directions, so there are two directions of rotation change with each fan. Thus, the circulating means passes through the sequence of Umwälzzustände z ' ₁ , z' ₂ , z ' ₃ , z' ₄ , with corresponding Umwälzzustände are designated the same, but simply deleted. Subsequently, a new cycle begins by passing through the states z '' ₁ , z '' ₂ , z '' ₃ and z '' ₄ by corresponding reversion of the direction of rotation at the times t ₈ , t ₉ , t ₁₀ , t ₁₁ and t ₁₂ ,

As mentioned above, the time t ₁ to t ₃ , in which the second fan is rotated in a first direction of rotation, the time period t ₃ to t ₅ , ie the period during which the second fan is rotated in the opposite direction. In addition, the time periods t ₀ to t ₁ (because of t ₀ = 0 sec equal to t ₁ ), t ₁ to t ₂ (ie t ₂ - t ₁ ), etc. are also the same length, so in particular there is a reversal of the direction of rotation second fan at the time t ₁ , which corresponds to half the time period between t ₀ and t ₂ . The time offset between a reversal of rotation of the first fan and the second fan thus corresponds to half the period of rotation in a respective direction of rotation.

In 2 is graphically over time the rotational speed v _{d of} a circulating device comprising a single fan, shown, however, for different cooking periods or durations of a Garprozessschrittes. A first graph 10 Graphically shows the rotational speed for a cooking time of 12 minutes, while a graph 12 represents the rotational speed for a cooking process with a duration of 48 minutes and the graph 14 the speed of rotation for a cooking time longer than 48 or more than 64 minutes. For the graph 10 As a result, a cycle duration that corresponds to a minimum cycle duration, since only two cycles are run through, was chosen to be four minutes. The cooking time of 12 minutes is therefore below a maximum duration, for example 32 minutes. If the cooking time is increased, in particular extended to 48 minutes, ie greater than the minimum duration of 32 minutes but less than a maximum duration of, for example, 64 minutes selected, the first and second time period is evenly extended so that a total cycle time of 6 minutes results. This cycle time is achieved by dividing the entire cooking time of 48 minutes by eight cycles, resulting in a cycle time of six minutes and thus a first and a second period of three minutes each. If the cooking time is further extended, the cycle time is also increased to a point where a maximum cycle time, in this case eight minutes, is reached, that is, the first and second time periods reach four minutes. Then the maximum duration of 64 minutes is exceeded. If there is a further increase in the cooking time, the number of cycles is further increased. However, the time period is not further increased so that, since there is only one fan wheel, a state change occurs every four minutes and a cycle of eight minutes each is passed through.

In 3 are graphically the rotational speeds v _{d of} a circulating device, which also includes two fan wheels shown. The dates corresponding to those of 2 represented by the same application, bear the same reference number, but deleted twice. At time t _{4 ''} is a by a graph 16 '' Desired target cooking temperature GT _{setpoint is} changed such that either a threshold value, for example 120 ° C, is exceeded or the temperature change, that is, the difference between a cooking space actual temperature and a cooking space setpoint temperature, exceeds a threshold. As is apparent from the graph 3 '' and 16 '' results, until the time t _{4 ''} a cycle time passes through, which corresponds to a maximum cycle time, while at time t _{4 ''} due to the temperature change minimizes the cycle time, in particular to the minimum cycle time, is reduced. It follows that for a passage of Umwälzzuständen z ₅ to z ₈ a longer time elapses than for a passage through the Umwälzzustände z ₉ to z ₁₆ .

In 4 Over time, a rotational speed v _{d of} a circulating device comprising a single fan wheel is shown. A graph 18 describes the rotational speed v _d . There are shown different cooking process steps and beyond an actual temperature GT _is a cooking space as a graph 20 shown graphically. Again 5 can be seen, during a cooking process step, which includes in particular a preheating, no reversing of the fan made during a loading phase rotation of the fan completely off and during a load detection also no reversing the rotational movement of the fan is made. However, this changes during a searing phase, which is so short that the minimum value is selected as the cycle time or as the time span. On the other hand, in the subsequent cooking phase, which involves cooking, a cooking process step is carried out so long that the maximum cycle time is set and, in particular, the number of cycles is increased beyond the number eight.

Finally, in 5 as a graph 22 graphically the rotational speed v _{d of} a circulating device comprising a single fan shown, wherein at a time t = 12 minutes, an adaptation of a cooking time in the form that the cooking time is extended, with the result that at the same time the cycle time of 4 minutes to 6 minutes or the time period for the respective directions of rotation of 2 Minutes is increased to 3 minutes.

The features disclosed in the foregoing description, in the claims and in the figures may be essential to the invention in its various embodiments both individually and in any combination.

LIST OF REFERENCE NUMBERS

1, 1 ''

graph

3, 3 ''

graph

5, 5 ', 7, 7', 9, 9 ', 11, 11'

Change of direction

10

graph

12

graph

14

graph

16 ''

graph

18

graph

20

graph

t _0, t _1, t _2, t _3, t _4, t _5, t _6, t _7, t _8, t _9, t _10, t _11, t ₁₂

time

t ₀ ", t ₁ ", t ₂ ", t ₃ ", t ₄ ", t ₅ ", t ₆ ", t ₇ ", t ₈ ", t ₉ ", t ₁₀ ", t ₁₁ ", t ₁₂ "

time

z ₁ , z ₂ , z ₃ , z ₄ , z ₁ ', z ₂ ', z ₃ ', z ₄ ', z ₁ ", z ₂ ", z ₃ ", z ₄ "

Umwälzzustand

z ₅ , z ₆ , z ₇ , z ₈ , z ₉ , z ₁₀ , z ₁₁ , z ₁₂ , z ₁₃ , z ₁₄ , z ₁₅ , z ₁₆

Umwälzzustand

Δt ₁ , Δt ₂ , Δt ₃ , Δt ₄

Period of time

v _d

rotation speed

GT _is

Actual oven temperature

GT _should

Actual oven temperature

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 6346691 B2 [0002]
• WO 84/01266 A1 [0003]
• DE 2403294 C2 [0004]
• DE 3031041 C2 [0005]
• US 2003/0000515 A1 [0006]
• US 4467777 [0007]
• DE 10316503 B3 [0008, 0008]

Claims (15)

Method for carrying out a cooking process in at least one cooking chamber of a cooking appliance with at least temporary heating of the cooking chamber by means of a circulation device, wherein during at least one cooking process step of the cooking process at least a first impeller of the circulating device is driven about a first axis of rotation such that at least one first change of direction ( 5 . 5 ' ) from a first rotational state, in which the first fan wheel is rotated in a first rotational direction, to a second rotational state, in which the first fan wheel is rotated in a second rotational direction opposite to the first rotational direction, and then a second rotational direction change (FIG. 7 . 7 ' ) are performed from the second rotational state to the first rotational state, characterized in that the duration of a cycle comprising at least two first rotational direction changes ( 5 . 5 ' ), between which a second change of direction ( 7 ), is set in response to at least a first parameter of the cooking process, this cycle time being selected to be longer than a predetermined first minimum cycle duration of more than zero seconds and less than a predetermined first maximum cycle duration, and the first minimum cycle duration and the first maximum cycle duration independent of be given the first parameter. A method according to claim 1, characterized in that at least one second impeller of the circulating means is rotated at least temporarily, at least temporarily, over a second rotation axis, in particular substantially parallel to the first axis of rotation, during the cooking process, at least one third change of direction ( 9 . 9 ' ) of a third rotational state in which the second fan is rotated in a third rotational direction, which corresponds in particular to the first rotational direction, in a fourth Drehzzustand in which the second fan in a third rotational direction opposite, fourth rotational direction, in particular the second Corresponds to the direction of rotation, is rotated, and a fourth change of direction ( 11 . 11 ' ) from the fourth rotation state to the third rotation state. A method according to claim 1 or 2, characterized in that during at least a first cooking process step, the first fan and / or the second fan is not reversed, the first Garprozessschritt preferably a preheating, cooling, load detection and / or a holding phase in which preferably no food in the oven is arranged , includes and / or during at least a second cooking process step, which includes in particular a Beschwadung, the direction of rotation of the first fan and / or the second fan is not changed. A method according to claim 2 or 3, characterized in that the third change of direction ( 9 ) by a first time offset (t ₃ - t ₂ ) delayed to the second direction of rotation change ( 7 ) and / or the fourth change of direction ( 11 ) by a second time offset (t ₁ ) delayed to the first change of direction ( 5 ) Is carried out or will be, and the first time offset (t ₃ - t ₂₎ and / or the second time offset (t ₁₎ in response to a third parameter of the cooking process is determined, or are. A method according to claim 4, characterized in that the first time offset (t ₃ - t ₂₎ from the half of the first period of time (At ₁₎ and / or the second time offset (t ₁₎ of half of the second period of time (At ₂₎ is deviated or deviate, wherein preferably the third parameter is representative of an asymmetry of a loading of the cooking chamber with food to be cooked. Method according to one of claims 2 to 5, characterized in that a plurality of second fan wheels is used, wherein two third direction of rotation of two second fan wheels to a third time delay delayed each other and / or two fourth directions of rotation of two second fan wheels by a fourth time delay delayed from each other, are performed, wherein preferably the third time offset corresponds to the first time offset and / or the fourth time offset and / or the fourth time offset corresponds to the second time offset, and / or Preferably, the third time offset and / or the fourth time offset depending on at least a fourth parameter of the cooking process, which preferably corresponds to the third parameter, is set or be. A method according to claim 6, characterized in that the third time offset is selected equal to half the third time span and / or the fourth time offset is chosen equal to half of the fourth time period or in particular as a function of the fourth parameter representative of an asymmetry of a loading of the cooking chamber with food to be cooked, the third time offset deviates from the half of the third time span and / or the fourth time offset deviates from the half of the second time span. Method according to one of the preceding claims, characterized in that as the first parameter, the second parameter, the third parameter and / or the fourth parameter of the cooking process • at least one cooking parameter, in particular a duration of the cooking process, a duration of the cooking process step, a remaining time of Cooking process, a residual duration of the cooking process step, a temperature, a cooking chamber temperature, an ambient temperature of the cooking appliance, a humidity, a Garraumfeuchte and / or ambient humidity of the cooking appliance, a degree of loading, a load distribution in the oven, a density of ambient atmosphere, a geodetic height of a site the cooking appliance and / or an opening time of a cooking chamber door, and / or • at least one Gargutparameter, in particular a Gargutart, Gargutgröße, a Gargutausgangszustand, a Garguttemperatur, a degree of cooking and / or a degree of hygiene, and / or • a desired value of the Garparameters and / or Gargutpara meters, an actual value of the cooking parameter and / or cooking product parameter and / or a difference value between the desired value and the actual value is selected. Method according to one of the preceding claims, characterized in that the minimum cycle duration, the maximum cycle duration, the first minimum value, the second minimum value, the first maximum value and / or the second maximum value depending on the presence and / or the number of second fan wheels, an operating parameter and / or a parameter of the cooking appliance and / or the circulation device, preferably an energy intake, a heat output, an electrical resistance, an impedance, an ohmic resistance, a sound level and / or a time period for the first change of direction ( 5 . 5 ' ), second change of direction ( 7 . 7 ' ), third change of direction ( 9 . 9 ' ) and / or fourth change of direction ( 11 . 11 ' ), is given or will be. A method according to claim 9, characterized in that an operating parameter and / or a parameter of a drive unit of the first fan and / or the second fan is selected and / or the operating parameters and / or the characteristic during a first change of direction ( 5 . 5 ' ), second change of direction ( 7 . 7 ' ), third change of direction ( 9 . 9 ' ) and / or fourth change of direction ( 11 . 11 ' ) is determined. Method according to one of the preceding claims, characterized in that the cycle duration equal to the minimum cycle duration is selected if the total duration of the cooking process and / or the cooking process step falls below a predetermined minimum duration, and / or the cycle duration equal to the maximum cycle duration is selected if the total duration of the cooking process and / or the cooking process step exceeds a predetermined maximum duration. Method according to one of the preceding claims, characterized in that the cycle duration, the first period of time (Δt ₁ ), the second period of time (Δt ₂ ), the third period of time (Δt ₃ ) and / or the fourth period of time (Δt ₄ ) is set or, during the entire cooking process and / or the entire cooking process step, a predetermined number of cycles are passed if the duration of the cooking process and / or the cooking process step exceeds a time duration greater than the predetermined number of cycles multiplied by and less than the minimum cycle duration predetermined number of cycles multiplied by the maximum cycle duration is given. Method according to one of the preceding claims, characterized in that the cycle duration, the first period of time (Δt ₁ ), the second period of time (Δt ₂ ), the third period of time (Δt ₃ ) and / or the fourth period of time (Δt ₄ ) is reduced or reduced , in particular the cycle duration equal to the minimum cycle duration and / or the first time span (Δt ₁ ) and / or the second time span (Δt ₂ ) equal to the first minimum value and / or the third time span (Δt ₃ ) and / or the fourth time span ( Δt ₄ ) is set equal to the second minimum value, when the first parameter, the second parameter, the third parameter and / or the fourth parameter is changed during the cooking process and / or the cooking process step, the difference value of the temperature exceeds a first threshold value, the desired value of the temperature exceeds a second threshold value and / or the duration of the cooking process and / or the cooking process step is shortened. Method according to one of claims 1 to 12, characterized in that the cycle duration, the first time period (At ₁ ), the second time period (At ₂ ), the third time period (At ₃ ) and / or the fourth time interval (At ₄ ) increases is, in particular the cycle duration equal to the maximum cycle duration and / or the first time period (.DELTA.t ₁ ) and / or the second time period (.DELTA.t ₂ ) equal to the first maximum value and / or the third time period (.DELTA.t ₃ ) and / or the fourth time period (.DELTA.t ₄ ) is set equal to the second maximum value when the first parameter, the second parameter, the third parameter and / or the fourth parameter is changed during the execution of the cooking process and / or the cooking process step, since the difference value of the temperature is a third threshold falls below, the target value of the temperature falls below a fourth threshold and / or the duration of the cooking process and / or the cooking process step is extended. Method according to one of the preceding claims, characterized in that the rotational speed of the first fan wheel and / or the second fan wheel in dependence on the first parameter, the second parameter, the third parameter and / or the fourth parameter is changed.

Images