(19)
(11) EP 2 001 266 A1

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication:
10.12.2008 Bulletin 2008/50

(21) Application number: 07011312.1

(22) Date of filing: 08.06.2007
(51) International Patent Classification (IPC): 
H05B 3/74(2006.01)
H05B 6/12(2006.01)
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR
Designated Extension States:
AL BA HR MK RS

(71) Applicant: Electrolux Home Products Corporation N.V.
1930 Zaventem (BE)

(72) Inventor:
  • Herzog, Michael
    91610 Insingen (DE)

(74) Representative: Hochmuth, Jürgen 
c/o AEG Hausgeräte GmbH Group Intellectual Property
90327 Nürnberg
90327 Nürnberg (DE)

   


(54) Cooking hob


(57) The invention relates to a Cooking hob (2), wherein the hob (2) has a plurality of heating elements (3, 3', 3", 3"', 3"") and wherein the heating elements (3, 3', 3", 3"', 3"") have a rectangular shape. To improve the flexibility of the hob, the invention is characterized in that each heating element (3, 3', 3", 3"', 3"") is controlled separately by a controlling device (4, 4', 4", 4"', 4"") and groups of adjacent heating elements can be switched together and/or activated by the controlling device.




Description


[0001] The invention relates to a cooking hob, wherein the hob has a plurality of heating elements and wherein the heating elements have a rectangular shape.

[0002] Hobs of this kind are known for example from EP 0 921 711 A1. Here, an induction oven is disclosed which has a hob which is divided into separate,hob parts. All hob parts are equipped with rectangular induction coils. To reduce the space required for cooking using a certain number of cooking pots the disclosed induction oven supplies each hob part with two induction coils which are controlled together, i. e. dependently from each another.

[0003] It has been found that it is beneficial to improve such a hob so that a higher degree of flexibility can be obtained. The different cooking pots should be heated up in an optimal way dependent on their size. Also the introduction of heating energy should take place in an efficient way depending on the geometry of the cooking pots.

[0004] Therefore, it is an object of the invention to further develop a cooking hob according to the above mentioned kind, so that a plurality of cooking pots of different sizes can be heated up in an optimised way in term of energy consumption. So, the flexibility of the hob in the daily practice should be improved.

[0005] The solution of this object according to the invention is characterized in that each heating element is controlled separately by a controlling device and groups of at least two adjacent heating elements can be switched together and/or activated by the controlling device.

[0006] By designing a cooking hob in this way it becomes possible to focus or adapt the action of the different heating elements on the specific size of a cooking pot or utensil in which food is to be heated up, namely by selecting the group of heating elements on which the pot stands or which are closest to the pot by means of the controlling device.

[0007] Preferably a detection device, e.g. an inductive or capacitive detection device, is provided to detect on which of the heating elements the pot or cooking utensil is standing or is closest to and these heating elements are grouped together as a cooking zone or activated to heat the pot.

[0008] Preferably the heating elements are induction heating elements or coils. I this case the heating elements themselves can be part of an inductive detection device for detecting the presence and size of a cooking utensil or pot.

[0009] It is also possible that the heating elements are resistance heating elements.

[0010] The hob is preferably divided into at least two rows of hob parts which are arranged along a direction from the front side to the rear side of the hob, wherein each hob part has one heating element. Also it is beneficial that the hob is divided into at least four columns of hob parts which are arranged along a direction transversely to the direction from the front side to the rear side of the hob, wherein each hob part has one heating element.

[0011] The extension of the hob parts in the direction from the front side to the rear side is advantageously between 200 mm and 250 mm. The extension of the hob parts in the direction transversely to the direction from the front side to the rear side is preferably between 130 mm and 160 mm.

[0012] Preferably, the extensions of all hob parts are equal in the direction from the front side to the rear side; also the extensions can be equal in the direction transversely to the direction from the front side to the rear side.

[0013] In a preferred embodiment of the invention four or five hob parts are arranged along the direction transversely to the direction from the front side to the rear side and two hob parts are arranged along the direction from the front side to the rear side.

[0014] Preferably, each heating element is switchable on and off by a separate switch which is part of the controlling device. Also, a preferred embodiment comes up with each heating element being adjustable in its energy consumption by a separate switch which is part of the controlling device.

[0015] By this design of a cooking hob the flexibility is enhanced when using cooking devices of different sizes. It can be made sure that only the required area is heated up, depending on the specific geometry of the cooking dish.

[0016] In the drawings an embodiment of the invention is depicted.
Fig. 1
shows schematically a domestic oven in perspective view,
Fig. 2
shows a top plan view of the empty hob of the oven and
Fig. 3
shows the top plan view of the hob of the oven with different cooking pots.


[0017] Fig. 1 shows a domestic oven 1. On the upper surface of the oven 1 a cooking hob 2 is located. The hob is supplied with a plurality of heating elements 3. A selection of heating elements are numbered with 3', 3", 3"' and 3"". Each heating element 3 has a rectangular shape in the top view. As can be seen in fig. 2 each heating element 3 forms with regard to its extensions a respective part of the hob 2, i. e. a hob part.

[0018] It is an important feature of the present invention that each heating element 3, 3', 3", 3"', 3"" is controlled separately by a controlling device 4, 4'; 4", 4"', 4"". The switching on and off as well as the adjustment of the heating power is done by a number of switches 7, which are arranged in the front side 5 of the oven 1.

[0019] Each individual switch 7', 7", 7"', 7"" is connected to a separate controlling device 4, 4', 4", 4"', 4"" as illustrated in fig. 2.

[0020] So, it becomes possible to switch and to adjust each individual heating element 3', 3", 3"' and 3"" by a separate switch 7', 7", 7"' and 7"".

[0021] The arrangement and the relative size of the heating elements 3 are apparent from figures 2 and 3.

[0022] In the direction T from the front side 5 to the rear side 6 of the oven 1 two rows of heating elements 3 or hob parts are arranged.

[0023] In the direction B transversely to the direction T five columns of heating elements 3 or hob parts are arranged.

[0024] Consequently, the depicted embodiment of the hob 2 has 2 x 5 = 10 separate heating elements 3 which can be switched and/or adjusted separately.

[0025] The advantage of this design becomes apparent from fig. 3, which shows an example only for using the hob 2. Here, different cooking pots or cooking dishes are schematically depicted which are placed on the hob 2.

[0026] A big pot 8 is arranged on two of the hob parts or heating elements 3', 3" respectively. So, by activating the heating elements 3' and 3" the big pot 8 can be heated up'.

[0027] The hob part or heating element in the left upper corner is used when a small pot 9 is to be heated up.

[0028] The middle hob part or heating element in the upper row of heating elements is used when a pan 10 is to be heated up.

[0029] Finally, the four heating elements in the upper and lower row, which are located on the right side of the hob 2, are used to heat up a roasting tray 11. Here, the energy of four heating elements is employed.

[0030] So, the placement of cooking dished on the hob is more flexible compared with pre-known solutions.

[0031] The pot/dish/tray can be placed so that one heating element is covered - specifically the centre of it - and the boarder line between the different heating elements is not passed.

[0032] An alternative positioning is to place the pot/dish/tray so that more than one heating element is covered. Here, the common boarder line of two or more adjacent heating elements is not passed.

[0033] There is no fix zone or zone size on the hob; the effective area of the hob used for heating up a specific pot is adjusted and therefore optimized.

[0034] A preferred embodiment of the invention has a width of the oven 1 (in direction B) of about 80 cm. The effective width of the hob 2 (in direction B) is e. g. 715 mm. Here a single hob part or heating element 3 has a width of 143 mm.

[0035] The extension of the heating element or hob part in the direction T can be 227.5 mm, so that the total extension is 455 mm.

[0036] The cooking hob 2 can also be a built-in cooking hob instead of being part of an oven 1.

Reference Numerals



[0037] 
1
Domestic oven
2
Hob
3
Heating element
3', 3"
3"',
3""
Heating element
4
Controlling device
4', 4"
4"'
4""
Controlling device
5
Front side
6
Rear side
7
Switch
7', 7"
7"'
7""
Switch
8
Big pot
9
Small pot
10
Pan
11
Roasting tray
T
Direction
B
Direction



Claims

1. Cooking hob (2) having a plurality of heating elements (3, 3', 3", 3"', 3"") and wherein the heating elements (3, 3', 3", 3"', 3"") have a rectangular shape,
characterized in that
each heating element (3, 3', 3", 3"', 3"") is controlled separately by a controlling device (4, 4', 4", 4"', 4"") and groups of adjacent heating elements can be switched together and/or activated by the controlling device.
 
2. Cooking hob according to claim 1, characterized in that the heating elements (3, 3', 3", 3"', 3"") are resistance heating elements.
 
3. Cooking hob according to claim 1, characterized in that the heating elements (3, 3', 3", 3"', 3"") are induction heating elements.
 
4. Cooking hob according to at least one of claims 1 to 3, characterized in that the hob is divided into at least two rows of hob parts which are arranged along a direction (T) from the front side (5) to the rear side (6) of the hob, wherein each hob part has one heating element (3, 3', 3", 3"', 3"").
 
5. Cooking hob according to at least one of claims 1 to 4, characterized in that the hob is divided into at least four columns of hob parts which are arranged along a direction (B) transversely to the direction (T) from the front side (5) to the rear side (6) of the hob (1), wherein each hob part has one heating element (3, 3', 3", 3"', 3"").
 
6. Cooking hob according to claim 4 or 5, characterized in that the extension of the hob parts in the direction (T) from the front side (5) to the rear side (6) is between 200 mm and 250 mm.
 
7. Cooking hob according to at least one of claims 4 to 6, characterized in that the extension of the hob parts in the direction (B) transversely to the direction (T) from the front side (5) to the rear side (6) is between 130 mm and 160 mm.
 
8. Cooking hob according to at least one of claims 4 to 7, characterized in that the extensions of all hob parts are equal in the direction (T) from the front side (5) to the rear side (6).
 
9. Cooking hob according to at least one of claims 4 to 8, characterized in that the extensions of all hob parts are equal in the direction (B) transversely to the direction (T) from the front side (5) to the rear side (6).
 
10. Cooking hob according to at least one of claims 4 to 9, characterized in that four or five hob parts are arranged along the direction (B) transversely to the direction (T) from the front side (5) to the rear side (6) and that two hob parts are arranged along the direction (T) from the front side (5) to the rear side (6).
 
11. Cooking hob according to at least one of claims 1 to 10, characterized in that each heating element (3, 3', 3", 3"', 3"") can be switched on and off by a separate switch (7, 7', 7", 7"', 7"") which is part of the controlling device (4, 4', 4'', 4"', 4"").
 
12. Cooking hob according to at least one of claims 1 to 11, characterized in that each heating element (3, 3', 3", 3"', 3"") is adjustable in its energy consumption by a separate switch (7, 7', 7", 7"', 7"") which is part of the controlling device (4, 4', 4", 4"', 4"").
 
13. Cooking hob according to any of the preceding claims, comprising a detection device to detect on which of the heating elements the pot or cooking utensil is standing or is closest to, wherein the controlling device groups together or activates these adjacent heating elements as a cooking zone to heat the pot.
 
14. Cooking hob according to claim 13, wherein heating elements in each pair of adjacent hob parts in rows or columns can be jointly activated or switched on by the controlling device.
 




Drawing










Search report










Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description