EP3612002B1 - Cooking hob and method for controlling a heating device of a cooking hob - Google Patents

Description

Field of application and state of the art

The invention relates to a method for controlling a heating device of a hob and a corresponding hob. The hob has a number of heating devices under a hob plate and pot detection means for detecting a position of a cooking vessel on the hob plate.

From the EP 2 211 591 A1 It is known that in the case of an induction hob with a large number of induction heating coils as heating devices under a hob plate, those induction heating coils that are completely or at least 50% covered by the cooking vessel take on the task of heating an erected cooking vessel or its contents. If the cooking vessel is moved, for example deliberately into a new position, for example because more space is required on the hob plate or the cooking vessel is in the way at this point, a previous power level is taken along as a predetermined first surface power density for heating the cooking vessel. The shifted cooking vessel is also heated in the new position with this predetermined first areal power density. Thus, an operator is spared the expense of re-entering the previous power level or surface power density for the cooking vessel at its new position.

From the EP 3 297 397 A1 a method for operating a hob with a plurality of heating devices is known. Different heat outputs for a cooking vessel placed on the hob can be set by moving the cooking vessel on the hob and assigning different power densities to different positions. If the hob is moved, the performance actually changes. However, it is possible that an operator receives an option for a while after the shift to change a surface power density and thus a heating power for the cooking vessel according to his own choice. It is possible to deviate from the position-dependent heating.

From the FR 2 863 039 A1 an induction hob is generally known in which a plurality of heating devices are arranged under the hob plate. A cooking vessel placed on the hob plate is usually heated by several of these heating devices. Depending on how the heating device is covered by the cooking vessel, the heat output generated by this heating device can vary; in particular, it becomes smaller with less coverage.

task and solution

The invention is based on the object of creating a method as mentioned at the outset and a hob as mentioned at the outset, with which problems of the prior art can be avoided and in particular it is possible to control the hob in a practical and advantageous manner or to enable comfortable use, in particular when moving a cooking vessel.

This object is achieved by a method having the features of claim 1 and by a hob having the features of claim 13. Advantageous and preferred configurations of the invention are the subject matter of the other claims and are explained in more detail below. Some of the features are only described for the process or only for the hob. However, independently of this, they should be able to apply independently both to the method and to the hob.

The hob that can be operated with the method according to the invention and that is designed to carry it out has a hob plate and at least two heating devices under the hob plate. These are advantageously induction heating coils that can be operated individually or together in order to be able to heat a cooking vessel that has been set up. Furthermore, the hob has pot detection means to be able to detect a position of a cooking vessel on the hob plate. These pot detection means can be of general design, for example, be formed by the induction heating coils mentioned themselves or by additional sensor coils, for example according to FIG DE 10 2014 224 051 A1 . Alternatively, a camera or the like. be arranged above the hob and optically record the status or processes on the hob. Finally, the hob also has an operating device with operating elements and at least one display and a controller for the hob.

The method according to the invention can be carried out particularly well with such a hob. In this method, a cooking vessel is placed over a first heating device of the hob, possibly also over a number of heating devices or over a number of heating elements, which together can form a heating device corresponding to the cooking vessel. It is heated by this heating device with a relatively high first power, this relatively high first power being at least 50% of the permanently maximum possible power of the first heating device, ie at least 50% of a continuous rated power. This is important above all in the case of induction heating coils, which can also be operated in a so-called boost mode with a power that is higher than this rated continuous power, for example with up to 50% more. With this power, however, they can only be operated for a few minutes. However, the relatively high first power mentioned can also be such a boost power.

Provision can even be made for the stated first power to be at least 70% of the permanently maximum possible power. In the case of cooking levels, this can be from level 8.

Then the cooking vessel is shifted by at least 4 cm, possibly so far that it no longer covers this first heating device at all. This shifting is detected by a control of the cooktop, advantageously with the aid of the aforementioned pan detection means.

As a result of the detection of this displacement, the cooking vessel is heated with a second power, this second power being reduced in comparison to the first power. This second power is advantageously at least 10% to 50% lower than the first power. These Reducing the power for heating the cooking vessel from the first power to the lower second power is optically and/or acoustically signaled to an operator that they are actually doing this. Otherwise you could possibly assume that there is an error here, for example because the cooking image or the status in the cooking vessel has changed.

At the same time as the power is reduced, a counter starts counting down a predetermined decision time. This counting is optically and/or acoustically signaled to an operator as a process so that he can see it clearly. Advantageously, counting down a time is displayed visually as a countdown. In a first case, the operator does not react during the decision time, which in this case means that he does not change the heating power for this cooking vessel or at the previous first heating device or a new heating device that is now covered by the cooking vessel by moving . Provision can therefore be made for the operator to make an operator input for other cooking vessels or other hotplates formed for the cooking vessels, but this should then not count for the cooking vessel that has been moved. In a second case, the operator reacts during the decision time and changes the power, advantageously to a third power. This third service is particularly advantageously reduced in comparison to the first service, but this does not necessarily have to be the case. It can be at least 10% to 50% less.

Then, according to the invention, in the first case the cooking vessel is heated again permanently with the first power after the decision time has elapsed, this advantageously being done in such a way that the cooking vessel is heated again in absolute terms with the same power as before according to the first power. It is irrelevant whether this is done by just one heating device or by several, especially in the case of induction heating coils.

In the second case, the cooking vessel is permanently heated with the changed power after the power has changed, in particular to the third power mentioned, or after the decision time has elapsed, ie either immediately or only after the decision time has elapsed. This is preferably even with the third power.

This means that in a special application, namely the heating of a cooking vessel with a relatively high first power according to the above definition, when the cooking vessel is moved by an amount that actually means safe moving and can be recognized as such, the heating of the cooking vessel is initially reduced at the new position. Above all, this covers the case where there is water and food to be cooked, such as pasta or potatoes, in the cooking vessel. located. This requires high power, for example power level 9. When the water boils over, the operator's instinctive reaction is often to move the cooking vessel immediately, as with old cooktops with cast-iron hotplates. This displacement also has the advantage that the cooking vessel is then not only no longer or only slightly above the previously heating heating device, but with a certain probability is also standing on a cold area of the hob plate. This makes it a little cooler, so that the water stops boiling relatively quickly, which corresponds to the operator's instinctive reaction. The goal can thus be achieved here that the water in the cooking vessel stops boiling or boiling over as quickly as possible. However, if the operator then wants the water to continue to boil, this takes place automatically after the decision time has elapsed, for example after a few seconds. The operator then does not have to do anything else for this; he may be able to remove a lid from the cooking vessel, which means that boiling over can also be reliably avoided.

However, if the operator has not moved the cooking vessel because they want to stop or avoid annoying boiling over, but for other reasons, i.e. consciously and purposefully, for example due to lack of space, they can still change the power during the decision-making time so that no longer the original first service is available. In terms of content, this may be related to the fact that she moved the cooking vessel. It is possible that she fried or boiled something at high power in the cooking vessel in the front area of the hob for a short time, which then needs to be further cooked at a lower power in the rear area of the hob to which the cooking vessel has been moved. Possibilities for setting such a different or lower power are explained in more detail below.

Thus, with the invention, an operator can be informed on the one hand about the change or reduction in power. At the same time, she is asked to do so or has it in her hands to make the service valid again without intervention. Alternatively, through direct intervention, it can determine the power setting.

The minimum displacement path mentioned can advantageously be greater than 4 cm, particularly advantageously greater than 10 cm. This means that a very slight displacement of the cooking vessel, for example by 1 cm to 4 cm, which can also happen unintentionally, should have no effect or the cooking vessel is then heated as before without the intervention of a hob controller. A displacement direction can generally be neglected. It can thus be taken into account that several cooking vessels can stand on the hob plate when in use and shifting is not always only possible or takes place to the rear, which is probably the most common and simplest case, but may also have to be carried out diagonally to the rear, possibly also to the front.

The method is particularly advantageous when the cooking vessel is clearly displaced in such a way that the cooking vessel is completely removed from the first heating device and is moved over at least one second heating device. At this point, the cooking vessel should then be heated by at least the second heating device with the second output, at least for the decision time.

A third case can also be provided in the invention, namely that the operator reacts during the decision time, ie before it expires, and actuates an operating element. This can advantageously be a specific operating element that is precisely provided for this purpose. The decision time is then aborted immediately, i.e. it is no longer counted. Furthermore, the cooking vessel is then immediately heated again with the original first output. This covers the aforementioned option that the operator wants the cooking vessel to continue to be heated at the first power. Furthermore, in this third case, the possibility should also be covered that the operator moves the cooking vessel back to its original position, that is to say shifts the cooking vessel again, so to speak.

Furthermore, it can advantageously be provided that the second power is reduced by approximately 25% to 40% compared to the first power. It is therefore not reduced quite as much, but is nevertheless strong enough to briefly interrupt the process of boiling water in the cooking vessel, for example, and thus prevent it from boiling over.

In an embodiment of the invention, it can be provided that the aforementioned relatively high power is a surface power density of more than 3.5 W/cm ² . It can also be more than 5 W/cm ² or even more than 7 W/cm ² corresponding to a level 8 or 9 as the power level or cooking level.

In a further embodiment of the invention, it is advantageous to visually display to the operator the counting of the decision time as a process during the process. This can be done every second, for example. A decreasing or also an increasing number on a display of the hob can be used for this purpose. Likewise, alternatively or additionally, a decreasing or increasing progress bar can be used for the display. For this purpose, for example, so-called bar displays for sliders can be used as control elements for setting the power, as is particularly the case in DE 10 2004 044 355 are known.

A visual display of counting down as the decision time has elapsed can also be done by flashing. An aforesaid number or a aforesaid progress bar can flash, which ensures particularly well that the operator notices this.

In a further embodiment of the invention, it can be provided that, in a fourth case, the operator reacts during the decision-making time and, by actuating a control element, in particular a control element specially provided for this purpose, sets the power permanently to the second power in order to continue heating the cooking vessel . The operator can thus set the second service as a permanent additional service before the decision time has elapsed, for example because the operator considers this service to be advantageous.

In yet another embodiment of the invention, it is provided that the power currently used for heating the cooking vessel is displayed as a number or as a power display. This then advantageously corresponds to a power level. In this way, the operator always knows at a glance how intensely the cooking vessel is being heated at any given time.

Within the scope of the invention, a heating device can be understood in such a way that it does not have just a single heating element. Thus, for example, two to four induction heating coils can be used together to heat a single cooking vessel and can then be viewed as a heating device with the same power, at least the same surface power and/or absolute power.

A hob with which the above-described method can be carried out advantageously has more than the usual four or six heating devices for four or six discrete hotplates. For example, at least two times three or two times four heating devices can be provided, in particular three times four heating devices. their arrangement should be regular so that a good coverage of the hob plate is achieved.

These and other features emerge not only from the claims but also from the description and the drawings, with the individual features being realized individually or in combination in the form of subcombinations in one embodiment of the invention and in other areas and are advantageous and protectable in themselves Designs may represent for which protection is claimed here. The subdivision of the application into individual sections and subheadings do not limit the general validity of the statements made thereunder.

Brief description of the drawings

Fig. 1

eine Draufsicht auf ein Induktionskochfeld mit mehreren Induktionsheizspulen, zwei darüber aufgesetzten Kochgefäßen und einer Bedieneinrichtung mit Slidern und Anzeigen,

Fig. 2

eine vergrößerte Darstellung des linken vorderen Bereichs der Bedieneinrichtung mit Einstellung einer ersten Leistung für das linke Kochgefäß vor einem Verschieben,

Fig. 3

eine vergrößerte Darstellung des linken vorderen Bereichs der Bedieneinrichtung mit reduzierter zweiter Leistung für das linke Kochgefäß nach einem Verschieben,

Fig. 4

das Darstellen des Abzählens der Entscheidungszeit an einem Slider mit einzelnen Leuchtsegmenten und an einer Sieben-Segment-Anzeige mit Ziffern,

Fig. 5

der linke vordere Bereichs der Bedieneinrichtung mit erneuter Einstellung der ersten Leistung für das weitere Beheizen für das linke Kochgefäß nach einem Ablauf der Entscheidungszeit ohne Reaktion der Bedienperson.

Exemplary embodiments of the invention are shown schematically in the drawings and are explained in more detail below. In the drawings show:

1

a top view of an induction hob with several induction heating coils, two cooking vessels placed above it and a control device with sliders and displays,

2

an enlarged representation of the left front area of the operating device with a first power setting for the left cooking vessel before it is moved,

3

an enlarged view of the left front area of the operating device with reduced second power for the left cooking vessel after being moved,

4

the display of counting down the decision time on a slider with individual light segments and on a seven-segment display with digits,

figure 5

the front left area of the operating device with renewed setting of the first output for further heating for the left cooking vessel after the decision time has elapsed without a reaction from the operator.

Detailed description of the exemplary embodiments

In the 1 1 shows a plan view of an induction hob 11 according to the invention, described at the outset, for carrying out the method according to the invention, which has a hob plate 12 . The rear and by far the largest part of the hob plate 12 forms a heating area 13 in order to be able to heat cooking vessels or pots that have been set up therewith. Eight induction heating coils 15 are arranged under the heating area 13, here designated by HE10 to HE23. The left half of the heating area 13 has four induction heating coils 15 and the right half as well. However, this division is not absolutely necessary; fewer and, above all, even more induction heating coils could be provided for the entire heating area 13 .

A pot T1 as a cooking vessel is placed on the induction hob 11 at the front left. It largely covers the front left induction heating coil HE10. A larger oval pot T2 is set up on the right as a cooking vessel corresponding to a roaster, specifically approximately in the middle between the two induction heating coils HE20 and HE23 and on top of them.

In front of the heating area 13, the induction hob 11 has an operating device 17, advantageously arranged below the same hob plate 12 and implemented with touch switches, advantageously with capacitive sensor elements and illuminated displays or LEDs. The operating device 17 has four horizontally running so-called sliders 19a to 19d in a special distribution, which, however, does not play a significant role here. Each slider has ten luminous segments 20, with a separate sensor element also being provided on each luminous segment 20. Such a slider 19 is thus a type of illuminated touch strip. A display 21 is arranged to the right of each slider 19, so four displays 21a to 21d are also provided. The displays 21 each have two seven-segment displays for showing corresponding numerals and letters or symbols, as will be seen below Figures 2 to 4 is good to see.

In the 2 shows how the set target powers are shown on the operating device 17 by way of example. For the pot T1, the target output with the output level 8 is set on the lower left slider 19a. The power specification or power setting in stages is usual for hobs. This can be done by swiping with a finger above the slider 19a, alternatively by direct operation. If a finger is placed on the slider 19a over the second light segment 20a from the right, which is the ninth light segment seen from the left, power level 8 can also be set directly. In any case, the display 21a with the right digit indicates the power level 8 by lighting up, advantageously by lighting up constantly. The eight left-hand light segments 20a light up on the slider 19a itself and thus also illustrate the set high power level as the target power for the pot T1. The setting up of pots T1 and T2 may have been detected by the induction heating coils HE themselves. Alternatively, other sensors may have detected it.

Power level 8 corresponds to a surface power density of approximately 5 W/cm ² for pot T1. So this first achievement is a great achievement. If the first power was significantly less than 3.5 W/cm ² or less than 3 W/cm ² or less than a power level of “7” or “6” or below, the method according to the invention would not start and in particular no reduction in power in the new second position.

In a corresponding manner, a target power can be set for the right-hand pot T2 and displayed on the slider 19d and on the display 21a.

At any time, for example because water with noodles in it, which is to be cooked in the pot T1, is just boiling, the pot T1 is pushed backwards by the operator into the new second position T1'. This is intended as a quick response to the fact that the water in the pot T1 is about to boil over or is already boiling over, which is not desired by the operator. Displacement of the pot T1 is then at least subjectively or intuitively faster and more direct and more reliable for many operators than reducing the power using the operator control device.

In the new second position T1′, which is the distance d away from the original first position, this distance d being greater than a predetermined minimum displacement path of, for example, 4 cm or 10 cm, this position of the pot T1′ is first recognized again as before also the position T1. If the distance d were smaller than the minimum displacement path mentioned at the outset, no action would take place.

According to the invention, pot T1' is then operated with reduced power as the new second power. As a result, performance is reduced, and significantly so. This is done here at power level 4, which is again shown on the slider 19a by four luminous light segments 20a. The display 21a shows the power level 4 with the right digit. Advantageously, there is also an acoustic signal to the operator.

At the same time, a predetermined decision time begins to elapse or is counted down on a counter in the mentioned controller of the induction hob 11 . Here it is advantageously chosen to be 10 seconds. The expiry of this decision time is supposed to be displayed visually to an operator, this is in the 4 clarified. In each case on the left it is shown how only ten of these light segments light up on a slider 19 with the ten light segments 20, as shown at the very top. Only nine light segments then light up, then eight light segments 20, etc. Advantageously, one further light segment is extinguished per second, so that the decision time is optically counted down.

Alternatively or additionally, but advantageously only alternatively, the numerical counting of the decision time can be displayed as a kind of countdown on the display 21 with the seven-segment displays. At the very bottom, if the slider 19 shown on the left no longer lights up a light segment 20, then a "0" would light up on the right. Alternatively, the reduction in power can be shown on the display 21, for example by a letter like a "U". Again alternatively, the reduced second power can be shown on the display 21, ie the number 4 accordingly 3 , than the power actually used. For this reason, the decision time is advantageously counted off optically on the slider 19 . The expiry of the decision time can according to the 4 can also be displayed by flashing on the slider 19 or on its light segments 20 and/or on the display 21.

Within the elapsing decision time, the operator can now react as previously described. If it does not react at all within the decision time, the pot T1' in the new position is immediately operated again with the original first power, i.e. with power level 8, after the decision time has expired. This is shown in FIG. 6.

In the second case mentioned above, the operator reacts during the decision time of 10 seconds and changes the power to a third power with a control element or with the slider 19, which is still active despite displaying the end of the decision time. This third performance can be reduced compared to the first performance, but it need not be so. The third service can also correspond to the second service. Then, in this second case, the pot T1' in the new position is permanently heated with this third power immediately after the change to the third power. Alternatively, this can also only take place after the decision time has elapsed, but this is regarded as disadvantageous.

If the operator reacts while the decision time is being counted down, then in the third case mentioned he can actuate an operating element, advantageously a specific operating element provided for this purpose. This causes the immediate termination of the decision time and the counting of the decision time, with pot T1' then immediately being heated again with the first output.

In a fourth case mentioned above, the operator also reacts while the decision time is being counted down and actuates an operating element, advantageously an operating element specially provided for this purpose. In this way she can set the power permanently to the second power for heating the pot T1', for example because she has seen that this corresponds to the desire to heat the pot T1' in the new position.

The same applies to the pot T2 as previously described when it is moved to the new position T2'. It covers two induction heating coils in both positions, namely the induction heating coils HE20 and HE23 as pot T2, and the induction heating coils HE21 and HE22 as pot T2' in the shifted position. Here, too, if the pot is heated with a correspondingly high first power, the power is initially reduced after displacement by the distance d. The two induction heating coils are treated as one. It would be the same if a pot were moved from previously two induction heating coils to a single one, or if a pot were moved from previously a single induction heating coil to two. Seen in terms of the absolute power or a power level, it should change for the pot just as described above, regardless of the number of induction heating coils required. This applies at least as long as the desired service can be provided.

Claims (13)

1. Method for controlling a heating device (HE) of a cooktop (11), comprising the steps:

   - a cooking vessel (T) is placed over a first heating device (HE) of the cooktop (11) and is heated at a relatively high first power by said first heating device, wherein the relatively high first power is at least 50 % of the permanently maximum possible power of the first heating device (HE),

   - if the cooking vessel (T) is shifted by at least 4 cm,

   - the cooking vessel (T) is heated at a second power which is reduced in comparison to the first power,

   - this reduction in the power for heating the cooking vessel (T) from the first power to the second power is optically and/or acoustically indicated to an operator,

   - upon the reduction in power, a counter starts counting down a predetermined decision time, and this countdown is optically and/or acoustically indicated to an operator as an expiration,

   - wherein, in a first case, the operator does not react during the decision time,

   - wherein, in the first case, the cooking vessel (T) is again permanently heated at the first power after expiry of the decision time,

   - wherein, in a second case, the operator does react during the decision time and changes the power to a third power,

   - wherein, in the second case, the cooking vessel (T) is permanently heated at the third power after the change to the third power or after expiry of the decision time.
2. Method according to claim 1, characterized in that the cooking vessel (T) has to be shifted by at least 10 cm, preferably by at least the diameter of the cooking vessel (T), so that the shifting is identified as movement and is evaluated as such.
3. Method according to claim 1 or 2, characterized in that the cooking vessel (T) is removed from the first heating device (HE) and is moved over a second heating device (HE), and is then heated at the second power by at least the second heating device (HE).
4. Method according to any of the preceding claims, characterized in that, in a third case, the operator reacts during the decision time and by actuating an operator control element (19), preferably of a specific operator control element intended for that purpose, causes immediate termination of the decision time and the countdown of the decision time, wherein the cooking vessel (T) is then immediately heated again at the first power.
5. Method according to any of the preceding claims, characterized in that the second power is at least 10 % to 50 % lower than the first power, preferably it is 25 % to 40 % lower.
6. Method according to any of the preceding claims, characterized in that the third power is reduced in comparison to the first power.
7. Method according to any of the preceding claims, characterized in that the counting down in the form of an expiration of the decision time is optically displayed to the operator during the expiration, preferably in seconds, in particular by a decreasing or increasing number or by a decreasing or increasing progress bar.
8. Method according to claim 7, characterized in that the optical display of the counting down in the form of an expiration of the decision time is by flashing, preferably by a flashing representation of the number or the progress bar.
9. Method according to any of the preceding claims, characterized in that, in a fourth case, the operator reacts during the decision time and by actuating a specific operator control element sets the power permanently to the second power for heating the cooking vessel (T).
10. Method according to any of the preceding claims, characterized in that the respective currently used power for heating the cooking vessel (T) is displayed as a number or as a power display.
11. Method according to any of the preceding claims, characterized in that the heating device comprises two to four heating elements (HE) which are jointly operated at the same power density and/or power.
12. Method according to any of the preceding claims, characterized in that the heating device and the heating elements of the heating device, respectively, is/are induction heating coils (HE).
13. Cooktop (11) for carrying out the method according to any of the preceding claims, characterized in that the cooktop comprises:

    - a cooktop plate (12),

    - at least two heating devices (HE) below the cooktop plate (12),

    - pot identification means (HE) for identifying a position of a cooking vessel (T) on the cooktop plate,

    - an operator control device (17) having operator control elements (19) and displays (20, 21), and

    - a controller for the cooktop (11), wherein the controller is configured for carrying out the method according to any of the preceding claims.

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