(19)
(11) EP 1 166 016 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
09.06.2004 Bulletin 2004/24

(21) Application number: 00909059.8

(22) Date of filing: 06.03.2000
(51) International Patent Classification (IPC)7F24C 7/08
// (F24C7/02, 15:02, H05B6:80)
(86) International application number:
PCT/DK2000/000093
(87) International publication number:
WO 2000/052392 (08.09.2000 Gazette 2000/36)

(54)

A DEVICE FOR TERMINATING COOKING AND INDICATING STATUS

EINRICHTUNG ZUM ANZEIGEN DES ENDES EINES KOCHZYKLUSSES UND KOCHZUSTANDES

DISPOSITIF PERMETTANT DE SIGNALER LA FIN DE LA CUISSON AU FOUR ET D'INDIQUER L'ETAT DUDIT FOUR


(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

(30) Priority: 04.03.1999 DK 31399

(43) Date of publication of application:
02.01.2002 Bulletin 2002/01

(73) Proprietor: Aktiebolaget Electrolux
105 45 Stockholm (SE)

(72) Inventors:
  • ESKILDSEN, Christian
    DK-5591 Gelsted (DK)
  • JEANNETEAU, Laurent
    F-60200 Compiègne (FR)

(74) Representative: Svahn, Göran et al
AB Electrolux Group Intellectual Property
105 45 Stockholm
105 45 Stockholm (SE)


(56) References cited: : 
GB-A- 2 302 188
US-A- 5 767 493
JP-A- 9 033 051
   
  • PATENT ABSTRACTS OF JAPAN & JP 09 033 051 A (SANYO ELECTRIC CO LTD) 07 February 1997
   
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description


[0001] The invention relates to a device for terminating cooking and indicating the status at the finishing time of a cooking programme in an oven for the preparation of food comprising an oven cavity and an oven door.

[0002] Ovens which are set by a timer to a finishing time are well known and they exist in simple user-set versions or in more elaborate versions where the finishing time is calculated internally in the oven control circuitry, e.g. by measured parameters. Simple ovens may be set to switch-off the power supply at the finishing time, and more elaborate ovens may calculate the remaining heat in the oven and perform the switching-off before the actual finishing time. The parameters measures may be temperature, humidity or composition of fumes developed within the cavity, and advanced data processing may be used in order to determine the development of cooking in each particular instance.

[0003] The known methods are not suitable for all cooking/baking, in particular for food which is designed to be taken out of the hot cavity at the correct instant. In such cases, it is not a question of programming the oven to switch off but to programme the user to act, either at a given time or when a specific condition of done-ness has been established in the oven. The reaction of a user - or the non-reaction, as the case may be - is an impredictable parameter, and hence known ovens do not give the impression of functioning properly at all times. Simply put, if the user forgets to take the food out of the oven at the correct time, it will be overcooked. There is hence a need to provide technical means to minimise the consequences of lack of user cooperation. There is a further need to communicate to the user by other means than the activation of a sounder, such as the ringing of a bell.

[0004] JP-A-9-33051 discloses a device for terminating cooking and indicating the status in an oven for the preparation of food comprising an oven cavity and an oven door. The advent of the finishing time triggers the release of the oven door so that it opens positively.

[0005] It is the purpose of the invention to provide an oven in which the above disadvantages and limitations have been eliminated in an efficient and economic manner.

[0006] This is achieved in an oven which has obtained the characterizing features indicated in claim 1.

[0007] In an advantageous embodiment the primary opening of the door is only partial. This has the advantage of preserving child safety, preventing access to the escaping steam and fumes. Such a positive partial opening may be followed by a full opening after an optional cooling-off period.

[0008] A further embodiment is particular in that the triggering of the door opening is obtained by means of signals from smoke detecting means. This has the added advantage that an erroneous adjustment of the cooking parameters at the initiation of cooking will not result in charred food, because the door opens and the oven switches off. As a minimum result of this provision, the need for cleaning of the cooking vessels and oven are simplified, and there is an increased chance of re-cooking and obtaining useful cooked food in spite of the original erroneous adjustment.

[0009] A further embodiment is particular in that the triggering of the door opening is obtained by means of signals representative of a reduction of the amount of steam developed over time. This feature is food dependent and would represent e.g. cakes and bread.

[0010] The fundamental aspect of the invention is the combination of creating a fast normalisation of the cooked food with advertising that it is finished. This is brought about by the means defined in the claims. A further aspect is that of safety, in particular for children, when a kitchen appliance which stores a large amount of thermal energy, suddenly releases it. Hence the provision of a gradual opening of the door in order to prevent children from obtaining direct access to large areas of hot surface. The triggering of the door release is obtained by a signal which represents that cooking has finished, and a number of signals may be used to this end. The door will not only be released, but it will be opened positively, i.e. by means of the release of energy stored in a spring or by means of a motor. The latter is the choice when the door is actually made like the front of a drawer which slides out from the oven.

[0011] The invention will be described more fully in the following with reference to the drawings in which

Fig. 1 shows a spring-loaded door with a trigger device and two-stage opening, and

Fig. 2 shows the cavity light intensity as a function of time and closure, respectively opening, of the oven door in the cases that a manual operation is performed or a triggered operation.



[0012] In Fig. 1 is shown an oven door which is closed shut against a spring force as a storage device, or a motor creating a suitable resistance. The oven door I is closed against the cavity 2 when it is at 0° opening angle. The spring arrangement 3 acts on a lever 5 at the bottom of the door (however, many practical, similar embodiments are possible) in order to open it against the resistance of the dashpot 6. The oven door is indicated in 3 positions: 0°, 15°, and fully open at 90°. The position of the door is linked to the level of light emitted by a suitably fitted lamp 7. A blower is connected to the space S and may through openings 8 blow a stream of air along the oven door 1 to draw fumes out and to cool the door when it is in the limited opening position at 15°. A humidity sensor 9 is connected to the control electronics 10 which in turn controls the blower and release means for the door C.

[0013] As shown in Fig. 2, upon closing the light in the cavity will gradually decrease, which is shown at the middle part of the graph (t3 - t4). If the oven is to be opened manually, this does not occur by pulling a handle, but by pushing a control button which is suitably linked to a catch C. The acutal opening does not occur until the light has increased gradually from zero (t1 - t2), and then the door opens, driven by a spring force or a motor but at a slow speed commensurate with the perceived speed in increasing the light. This is shown in the left-hand part of the graph. A suitable combination of the two speeds which will be easily determined by the skilled person will create a sense of elegance, of luxuriousness, thereby adding value to the product. Similarly, the closing of the door does not need to be performed manually but may occur through motor drive in conjunction with the changing light level.

[0014] In case the door opens because a cooking operation has finished, it has been found expedient to make a decided contrast in the manner in which the light inside the cavity changes, i.e. to let the opening be accompanied by a sudden increase in light. Alternatively, the light may be set to flash at an insistent rate, at least for the time that the oven door is only partly open, and changing for a stable light when the oven door is manually activated in order to remove the cooked food. This is shown in right-hand part of Fig. 2, in which it is seen that for the chosen opening angle of the oven door, in casu 15 °, the light flashes insistently until the time t6, whereupon it changes to normal combined opening and light change. During the time from t5 to t6 a blower fitted into the oven door drive compartment blows cooling air taken from outside the oven cavity over the inside of the door as well as carrying the smell of finished food into the living quarters.

[0015] The skilled person will be able to devise any suitable combination of light and opening according to special needs.


Claims

1. A device for terminating cooking and indicating the status at the finishing time of a cooking programme in an oven for the preparation of food comprising an oven cavity and an oven door, wherein the advent of the finishing time triggers the release of the oven door so that it opens positively, characterised in that the opening of the door is accompanied by a turning on of the oven cavity light and the oven door and oven cavity light are linked such that any manual closure or opening of the oven door causes a gradual change in light intensity from full light to dark and from dark to full light, respectively, whereas a cooking status triggered door operation causes a sudden light intensity change.
 
2. A device according to claim 1, characterised in that the triggering of the door opening is obtained by means of signals from smoke detecting means.
 
3. A device according to claim 1, characterised in that the triggering of the door opening is obtained by means of signals representative of a reduction of the amount of steam developed over time.
 
4. A device according to any of the preceding claims, characterised in that the advent of finishing time releases the door to a limited opening which is less than full opening.
 
5. A device according to claim 4, characterised in that a blower blows air taken from outside the oven cavity over the inside of the door in order for it to exit through the limited opening.
 


Ansprüche

1. Vorrichtung für die Beendigung des Kochvorganges und die Anzeige des Zustandes zum Zeitpunkt der Beendigung des Kochprogramms in einem Herd für die Zubereitung von Speisen, welcher eine Herdröhre und eine Herdklappe umfasst, wobei zum Endzeitpunkt die Freigabe der Herdklappe ausgelöst wird, so dass diese automatisch öffnet, dadurch gekennzeichnet, dass das Öffnen der Klappe vom Einschalten des Lichtes der Herdröhre begleitet wird und die Klappe und das Licht der Herdröhre dergestalt gekoppelt sind, dass jegliches manuelles Schließen oder Öffnen der Herdklappe eine allmähliche Veränderung der Lichtintensität von voller Helligkeit bis hin zur Dunkelheit bzw. von der Dunkelheit bis zur vollen Helligkeit bewirkt, wohingegen eine durch den Kochzustand ausgelöste Klappenbetätigung eine plötzliche Veränderung der Lichtintensität bewirkt.
 
2. Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, dass die Auslösung des Öffnens der Klappe mit Hilfe von Signalen erreicht wird, welche von Rauchdetektoren stammen.
 
3. Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, dass die Auslösung des Öffnens der Klappe mit Hilfe von Signalen erreicht wird, welche für eine Abnahme der Menge des im Verlauf der Zeit entwickelten Dampfes repräsentativ sind.
 
4. Vorrichtung gemäß einem beliebigen der vorangegangenen Ansprüche, dadurch gekennzeichnet, dass zum Endzeitpunkt die Klappe für ein beschränktes Öffnen frei gegeben wird, welches geringer als das vollständige Öffnen ist.
 
5. Vorrichtung gemäß Anspruch 4, dadurch gekennzeichnet, dass ein Gebläse Luft von außerhalb der Herdröhre über die Innenseite der Klappe bläst, so dass sie durch die beschränkte Öffnung austritt.
 


Revendications

1. Dispositif permettant de signaler la fin de la cuisson au four et indiquant l'état à la fin d'un programme de cuisson au four pour la préparation de nourriture comprenant une cavité de four et une porte du four, dans lequel l'arrivée à l'heure de fin déclenche le déblocage de la porte du four afin qu'elle s'ouvre de manière positive, caractérisé en ce que l'ouverture de la porte s'accompagne de l'activation de la lumière de la cavité du four et en ce que la porte du four et la lumière de la cavité du four sont liées de telle sorte qu'une fermeture ou ouverture manuelle de la porte du four entraîne un changement progressif de l'intensité de la lumière allant de l'éclairage complet au noir et du noir à l'éclairage complet, respectivement, alors qu'une action de la porte déclenchée par l'état de la cuisson entraîne un changement soudain d'intensité de la lumière.
 
2. Dispositif selon la revendication 1, caractérisé en ce que le déclenchement de l'ouverture de la porte est obtenu à l'aide de signaux provenant des moyens de détection de fumée.
 
3. Dispositif selon la revendication 1, caractérisé en ce que le déclenchement de l'ouverture de la porte est obtenu au moyen de signaux représentatifs d'une réduction du volume de vapeur développée dans la durée.
 
4. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que l'arrivée à l'heure de fin débloque la porte à une ouverture limitée qui est inférieure à l'ouverture complète.
 
5. Dispositif selon la revendication 4, caractérisé en ce qu'un ventilateur souffle de l'air de l'extérieur de la cavité du four vers l'intérieur de la porte afin de l'évacuer à travers l'ouverture limitée.
 




Drawing