BAKING OVEN

Description

[0001] The present invention relates to an oven, particularly a household baking oven, according to the preamble of claim 1. The present invention further relates to a method for operating an oven according to the preamble of claim 12.

[0002] Household baking ovens are usually equipped with several heating elements in order to provide the user the opportunity to run baking, roasting, broiling, frying or grilling oven programs for using a preparation process adapted to the respective food to be prepared. In general, there are ring-shaped heating elements known, which are operated in combination with a fan for oven programs using air recirculation for the distribution of heat within on oven compartment. Further, there are heating elements known for food treatment from above or from below, which are usually formed as tubular resistance heaters and which are operated, in that electric power being converted into heat energy.

[0003] Said heating elements for heating from above or from below are individually designed, each one in a way that the heat emitted from said heating elements is intended to be evenly distributed over the entire horizontal cross-sectional area of the oven compartment, either top-down by the top heat heating element or bottom-up by the bottom heat heating element. In order to realize said even distribution, particularly the top heat heating element comprises an outer and an inner loop-shaped heating rod or resistance heater, usually designed as tubular heating element, wherein said outer and inner loops comprise both bordering and inscribed loop portions.

[0004] It is an object of the present invention to provide an oven, particularly a household baking oven as well as a method for operating an oven, particularly a household baking oven, with particularly even heat distribution, especially when operating the oven with a grilling program or function considering particularly high energy efficiency.

[0005] The object is achieved for an oven, particularly a household baking oven, according to the preamble of claim 1 by means of the characterizing features of claim 1.

[0006] According to an aspect of the invention, an oven, particularly a household baking oven, comprises an oven compartment, an oven door closing the oven compartment at a front opening and a heating element arranged on a top side of the oven compartment for top heat food preparation, in particular for baking, roasting, broiling, frying and/or for grilling. The oven compartment is defined by a top wall, a bottom wall, a rear wall and side walls. The heating element comprises at least a first loop-shaped heating rod or resistance heater, particularly of tubular design, which first loop-shaped heating rod or resistance heater is preferably arranged in parallel to the top wall, and a second loop-shaped heating rod or resistance heater, particularly of tubular design, which second loop-shaped heating rod or resistance heater is preferably arranged in parallel to the top wall. Each of the first loop-shaped heating rod and the second loop-shaped heating rod is designed as a single-loop unit of at least essentially rectangular loop shape. The first loop-shaped heating rod frames an at least essentially rectangular first area and the second loop-shaped heating rod frames an at least essentially rectangular second area. The at least essentially rectangular first area is larger than the at least essentially rectangular second area. Preferably, the at least essentially rectangular second area is kept free from heating element sections or components.

[0007] In particular, the first loop-shaped heating rod encompasses the second loop-shaped heating rod. Preferably, the first loop-shaped heating rod and the second loop-shaped heating rod are arranged in the same plane.

[0008] The first loop-shaped heating rod and the second loop-shaped heating rod (15b') may have different geometries, but preferably they are geometrically similar parts.

[0009] According to specific embodiments, the first loop-shaped heating rod and the second loop-shaped heating rod are shaped as rounded-corner rectangles.

[0010] The oven compartment is particularly of an at least approximately cuboid shape and preferably comprises rounded-corner vertical side edges.

[0011] Each of the first loop-shaped heating rod and the second loop-shaped heating rod may comprise

• a front bar portion or rod portion arranged at least approximately in parallel to the oven door,
• left and right bar portions or rod portions arranged at least approximately in parallel to the side walls of the oven compartment, and
• at least one rear bar portion or rod portion arranged at least approximately in parallel to the rear wall of the oven compartment.

[0012] Each one of the front, the left and right and of the rear bar portions or rod portions of the first loop-shaped heating rod may be at least approximately equally spaced from one of the oven door, the side walls and the rear wall at a first distance, and each one of the front, the left and right and of the rear bar portions or rod portions of the second loop-shaped heating rod may be at least approximately equally spaced from one of the oven door, the side walls and the rear wall at a second distance. With such equal spacings, the heat portions emitted into directions towards the surrounding walls (including the door wall) may be similarly reflected and an even heat distribution within the oven compartment can be supported.

[0013] In a specific embodiment, the first and second loop-shaped heating rods or resistance heaters are individually controllable.

[0014] In particular, the second loop-shaped heating rod or resistance heater is concentrically arranged to the first loop-shaped heating rod or resistance heater, particularly differing only in the dimensions.

[0015] As mentioned above, the second loop-shaped heating rod or resistance heater frames an at least approximately rectangular second area, which is preferably kept free from heating element sections or components. "Kept free" in this context not only means that the second loop-shaped heating rod or resistance heater no longer comprises any indentation or recess entering into the at least essentially rectangular second area, as known from the prior art solution, but there is also no further heating element part or component, such as a third heating rod or third resistance heater, implemented in said at least essentially rectangular second area. The inventor has surprisingly found that, contrary to a skilled person's expectations, said keeping the interior of the heating element free from sections or components rather improves the even heat distribution over the entire horizontal cross-sectional area of the oven compartment, which results in the specific geometric conditions inside and adjusted constructions of the oven compartment. An example of a household baking oven with rectangular shaped heating elements is disclosed in EP2068083 A2.

[0016] A specifically preferred embodiment is characterized in that the at least essentially rectangular second area covers the centre zone of a horizontal cross-sectional area of the oven compartment, the at least essentially rectangular second area framing a ratio of at least 30%, particularly at least 35%, more particularly at least 40% of the horizontal cross-sectional area.

[0017] In particular, the first loop-shaped heating rod or resistance heater is operable with an electrical power having a value of between 50% and 80%, preferably of between 55% and 70%, more preferably of about 60%, in relation to the second loop-shaped heating rod or resistance heater.

[0018] The oven may comprise a first loop-shaped heating rod or resistance heater, which is operable with an electrical power between 0.9 and 1.7 kW, preferably between 1.1 and 1.5 kW, more preferably of about 1.3 kW. The oven may further comprise a second loop-shaped heating rod or resistance heater, which is operable with an electrical power between 0.5 and 1.1 kW, preferably between 0.65 and 0.95 kW, more preferably of about 0.8 kW.

[0019] The object is achieved for a method for operating an oven, particularly a household baking oven, which oven is designed according to anyone of the above-described embodiments, by means of the characterizing feature of claim 12.

[0020] According to a further aspect of the invention, a method for operating an oven, particularly a household baking oven, which oven is designed according to anyone of the above-described embodiments, comprises a control unit, which operates the heating element during a top heat food preparation operating program, in particular a baking, a roasting, a broiling, a frying and/or a grilling operating program.

[0021] A specific embodiment of the method provides for at least one of the first and the second loop-shaped heating rods or resistance heaters, which is operated during said top heat food preparation operating program. At least one of the first and the second loop-shaped heating rods or resistance heaters is preferably operated during a top heat baking, roasting, broiling and/or frying operating program and both the first and the second loop-shaped heating rods or resistance heaters are preferably operated during a grilling operating program.

[0022] Novel and inventive features of the present invention are set forth in the appended claims.

[0023] The present invention will now be described in further detail with reference to the drawings, in which

Fig. 1

illustrates a perspective partial view of a built-in oven with both a casing top wall and an oven compartment top wall being cut-away according to a prior art solution; and

Fig. 2

illustrates a similar perspective partial view of a built-in oven according to the present invention.

[0024] In Fig. 1, an electric household built-in oven 1 of the prior art is partly shown in a perspective view. In order to better illustrate the interior of a compartment 3 of the oven 1, a top wall of the compartment 3 as well as a top wall of an oven casing 5 surrounding the compartment 3 are cut away.

[0025] The compartment 3 is of a cuboid shape, comprising the cut-away top wall, a bottom wall 7, a rear wall 9 and two side walls 11a, 11b. On its front side, the compartment 3 is open for providing a loading opening for the food to be prepared in the oven 1. However, said loading opening is closed by the user by means of an oven door 13, which is pivotally arranged at the bottom side of the loading opening, after the loading of food.

[0026] Due to the top walls of the casing 5 and the compartment 3 being cut away, a top heat heating element 15 is visible. Said top heat heating element 15 is arranged inside of the compartment 3 close to the top wall of the compartment 3 in a parallel alignment thereto.

[0027] In the interior of the compartment 3, the oven 1 further comprises insertion supports 17 attached at the side walls 11a, 11b (only insertion support 17 at left side wall 11a shown) for receiving baking trays and supporting them during the cooking process.

[0028] The top heat heating element 15 comprises an outer loop-shaped heating rod 15a and an inner loop-shaped heating rod 15b, which are individually operable for modifiable heat emission. Therefore, terminals L, N are provided in order to connect the heating rods 15a, 15b for supply of electrical energy. A controller of the oven 1 can operate either the outer heating rod 15a or the inner heating rod 15b or both of them in a joint operation, depending on the needed heat input.

[0029] Both inner and outer heating rods 15a, 15b comprise inner and outer heat portions hp_i, hp_o, wherein the inner heating portion hp_i is Ω-shaped and the outer heating portion hp_o surrounds the inner heating portion hp_i with rectangular shape. That way, a radiant panel heating with uniform two-dimensional heat emission shall be simulated.

[0030] The top heat heating element 15 is supported by a supporting rod 21, which forms a horizontal support strut fixed between the side walls 11a, 11b and supporting the heating element 15 from below. Centrically, the supporting rod 21 comprises a fastening lug 23 for its further fixation at the top wall.

[0031] Finally, the oven 1 is also equipped with a temperature sensor 19 penetrating the compartment 3 at the upper left corner of the rear wall 9.

[0032] The oven 1' according to Fig. 2 is nearly identically constructed as the prior art oven 1. The two ovens 1, 1' illustrated in Figs. 1 and 2 only differ in the design of their heating elements 15, 15'. Also the heating element 15' of the oven 1' comprises an outer heating rod 15a' and an inner heating rod 15b'. However, according to the invention, both outer and inner heating rods 15a', 15b' are of a mere rectangular shape and do not comprise any inner heat portion.

[0033] The rectangular shapes of the outer and the inner heating rods 15a', 15b' are performed in a way that geometrical similarity is provided, so that the outer heating rod 15a' equidistantly surrounds the inner heating rod 15b'. More specifically, the outer and the inner heating rods 15a', 15b' comprise front, left side, right side and rear heating rod portions f, ls, rs, r, wherein the front heating rod portion f of the outer heating rod 15a' is arranged in parallel to the front heating rod portion f of the inner heating rod 15b' and both front heating rod portions f are spaced from each other in the same way as the left side heating rod portions ls as well as the right side heating rod portions rs of the outer heating rod 15a' and the inner heating rod 15b'. The same applies to the rear heating rod portions r, which, however, are divided in the middle for the branch of the terminals L', N' .

[0034] Like the heating element 15 of the prior art oven 1, also the heating element 15' of the oven 1' according to the invention is supported by a supporting rod 21', which supporting rod 21' and its centric fastening lug 23' are also fixed to the side walls 11a, 11b and to the top wall as it is in the prior art oven 1.

[0035] The front, left side and right side heating rod portions are designed with a dimension of at least 220 mm and the outer heating rod 15a'is operable with a power of 0.8 kW and the inner heating rod 15b' is operable with a power of 1.3 kW.

[0036] Although an illustrative embodiment of the present invention has been described herein with reference to the accompanying drawing, it is to be understood that the present invention is not limited to that precise embodiment, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope of the invention. All such changes and modifications are intended to be included within the scope of the invention as defined by the appended claims.

List of reference numerals

[0037] 

1

oven

3

compartment

5

casing

7

bottom wall

9

rear wall

11a, 11b

side walls

13

door

15, 15'

heating element

15a, 15a'

outer heating rod

15b, 15b'

inner heating rod

17

insertion support

19

temperature sensor

21, 21'

supporting rod

23, 23'

fastening lug

hp_i

inner heater portion

hp_o

outer heater portion

L, L', N, N'

terminals

f, ls, rs, r

front, left side, right side and rear heating rod portions

Claims

1. An oven (1), particularly a household baking oven, comprising

- an oven compartment (3) defined by a top wall, a bottom wall (7), a rear wall (9) and side walls (11a, 11b),

- an oven door (13) closing the oven compartment (3) at a front opening, and

- a heating element (15') arranged on a top side of the oven compartment (3), preferably in parallel to the top wall, for top heat food preparation, in particular for baking, for roasting, for broiling, for frying and/or for grilling, the heating element (15') comprising at least a first loop-shaped heating rod (15a') or resistance heater, particularly of tubular design, and a second loop-shaped heating rod (15b') or resistance heater, particularly of tubular design,

wherein each of the first loop-shaped heating rod (15a') and the second loop-shaped heating rod (15b') is designed as a single-loop unit of at least essentially rectangular loop shape, the first loop-shaped heating rod (15a') framing an at least essentially rectangular first area and the second loop-shaped heating rod (15b') framing an at least essentially rectangular second area, wherein the at least essentially rectangular first area is larger than the at least essentially rectangular second area and wherein the at least essentially rectangular second area is preferably kept free from heating element sections or components, characterized in that

the first loop-shaped heating rod (15a') or resistance heater is operable with an electrical power having a value of between 50% to 80%, preferably of between 55% and 70%, more preferably of about 60%, in relation to the second loop-shaped heating rod (15b') or resistance heater.

2. The oven (1) according to claim 1
characterized in that
the first loop-shaped heating rod (15a') encompasses the second loop-shaped heating rod (15b'), the first loop-shaped heating rod (15a') and the second loop-shaped heating rod (15b') preferably being arranged in the same plane.

3. The oven (1) according to claim 1 or 2,
characterized in that
the first loop-shaped heating rod (15a') and the second loop-shaped heating rod (15b') are geometrically similar parts.

4. The oven (1) according to anyone of the preceding claims, characterized in that
the first loop-shaped heating rod (15a') and the second loop-shaped heating rod (15b') are shaped as rounded-corner rectangles.

5. The oven (1) according to anyone of the preceding claims, characterized in that
the oven compartment (3) is of an at least approximately cuboid shape, preferably comprising rounded-corner vertical side edges.

6. The oven (1) according to anyone of the preceding claims, characterized in that
each of the first loop-shaped heating rod (15a') and the second loop-shaped heating rod (15b') comprise

- a front bar portion or rod portion (f) arranged at least approximately in parallel to the oven door (13),

- left and right bar portions or rod portions (ls, rs) arranged at least approximately in parallel to the side walls (11a, 11b) of the oven compartment (3), and

- at least one rear bar portion or rod portion (r) arranged at least approximately in parallel to the rear wall (9) of the oven compartment (3).

7. The oven (1) according to claim 6,
characterized in that

each one of the front (f), the left (ls) and right (rs) and the rear (r) bar portions or rod portions of the first loop-shaped heating rod (15a') is at least approximately equally spaced from one of the oven door (13), the side walls (11a, 11b) and the rear wall (9) at a first distance, and

each one of the front (f), the left (ls) and right (rs) and the rear (r) bar portions or rod portions of the second loop-shaped heating rod (15b') is at least approximately equally spaced from one of the oven door (13), the side walls (11a, 11b) and the rear wall (9) at a second distance.

8. The oven (1) according to anyone of the preceding claims, characterized in that
the first and second loop-shaped heating rods (15a', 15b') or resistance heaters are individually controllable.

9. The oven (1) according to anyone of the preceding claims, characterized in that
the second loop-shaped heating rod (15b') or resistance heater is concentrically arranged to the first loop-shaped heating rod (15a') or resistance heater.

10. The oven (1) according to anyone of the preceding claims, characterized in that
the at least essentially rectangular second area covers the centre zone of a horizontal cross-sectional area of the oven compartment (3), the at least essentially rectangular second area framing a ratio of at least 30%, particularly at least 35%, more particularly at least 40% of the horizontal cross-sectional area.

11. The oven (1) according to anyone of the preceding claims, characterized in that
the first loop-shaped heating rod (15a') or resistance heater is operable with an electrical power between 0.5 and 1.1 kW, preferably between 0.65 and 0.95 kW, more preferably of about 0.8 kW, and the second loop-shaped heating rod (15b') or resistance heater is operable with an electrical power between 0.9 and 1.7 kW, preferably between 1.1 and 1.5 kW, more preferably of about 1.3 kW.

12. A method for operating an oven (1), particularly a household baking oven, according to anyone of the preceding claims,
characterized in that
a control unit of the oven (1) operates the heating element (15') during a top heat food preparation operating program, in particular a baking, a roasting, a broiling, a frying and/or a grilling operating program.

13. The method according to claim 12,
characterized in that
at least one of the first and the second loop-shaped heating rods (15a', 15b') or resistance heaters is operated during the top heat food preparation operating program, preferably at least one of the first and the second loop-shaped heating rods (15a', 15b') or resistance heaters is operated during a top heat baking, roasting, broiling and/or frying operating program and both the first and the second loop-shaped heating rods (15a', 15b') or resistance heaters are operated during a grilling operating program.

Ansprüche

1. Ofen (1), insbesondere Haushaltsbackofen, umfassend

- ein Ofenfach (3), das durch eine obere Wand, eine untere Wand (7), eine Rückwand (9) und Seitenwände (11a, 11b) definiert ist,

- eine Ofentür (13), die das Ofenfach (3) an einer vorderen Öffnung verschließt, und

- ein Heizelement (15'), das auf einer oberen Seite des Ofenfachs (3), vorzugsweise parallel zur oberen Wand, zur Lebensmittelzubereitung mit Oberhitze, insbesondere zum Backen, zum Rösten, zum Braten, zum Frittieren und/oder zum Grillen, angeordnet ist, wobei das Heizelement (15') mindestens einen ersten schleifenförmigen Heizstab (15a') oder Widerstandsheizer, insbesondere mit rohrförmiger Ausgestaltung, und einen zweiten schleifenförmigen Heizstab (15b') oder Widerstandsheizer, insbesondere mit rohrförmiger Ausgestaltung, aufweist,

wobei sowohl der erste schleifenförmige Heizstab (15a') als auch der zweite schleifenförmige Heizstab (15b') als eine Einzelschleifeneinheit mit zumindest im Wesentlichen rechteckiger Schleifenform ausgestaltet ist, wobei der erste schleifenförmige Heizstab (15a') einen zumindest im Wesentlichen rechteckigen ersten Bereich umrahmt und der zweite schleifenförmige Heizstab (15b') einen zumindest im Wesentlichen rechteckigen zweiten Bereich umrahmt, wobei der zumindest im Wesentlichen rechteckige erste Bereich größer als der zumindest im Wesentlichen rechteckige zweite Bereich ist und wobei der zumindest im Wesentlichen rechteckige zweite Bereich vorzugsweise von Heizelementabschnitten oder -komponenten frei gehalten ist,

dadurch gekennzeichnet, dass

der erste schleifenförmige Heizstab (15a') oder Widerstandsheizer mit einer elektrischen Leistung betreibbar ist, die einen Wert zwischen 50 % bis 80 %, vorzugsweise zwischen 55 % und 70 %, stärker bevorzugt von etwa 60 %, in Relation zu dem zweiten schleifenförmigen Heizstab (15b') oder Widerstandsheizer aufweist.

2. Ofen (1) nach Anspruch 1
dadurch gekennzeichnet, dass
der erste schleifenförmige Heizstab (15a') den zweiten schleifenförmigen Heizstab (15b') umschließt, wobei der erste schleifenförmige Heizstab (15a') und der zweite schleifenförmige Heizstab (15b') vorzugsweise in derselben Ebene angeordnet sind.

3. Ofen (1) nach Anspruch 1 oder 2,
dadurch gekennzeichnet, dass
der erste schleifenförmige Heizstab (15a') und der zweite schleifenförmige Heizstab (15b') geometrisch ähnliche Teile sind.

4. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
der erste schleifenförmige Heizstab (15a') und der zweite schleifenförmige Heizstab (15b') als Rechtecke mit abgerundeten Ecken geformt sind.

5. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
das Ofenfach (3) zumindest annähernd quaderförmig ist, wobei es vorzugsweise vertikale Seitenkanten mit abgerundeten Ecken umfasst.

6. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
sowohl der erste schleifenförmige Heizstab (15a') als auch der zweite schleifenförmige Heizstab (15b') Folgendes umfassen

- einen vorderen Stangenabschnitt oder Stababschnitt (f), der zumindest annähernd parallel zur Ofentür (13) angeordnet ist,

- linke und rechte Stangenabschnitte oder Stababschnitte (ls, rs), die zumindest annähernd parallel zu den Seitenwänden (11a, 11b) des Ofenfachs (3) angeordnet sind, und

- mindestens einen hinteren Stangenabschnitt oder Stababschnitt (r), der zumindest annähernd parallel zur Rückwand (9) des Ofenfachs (3) angeordnet ist.

7. Ofen (1) nach Anspruch 6, dadurch gekennzeichnet, dass

jeder der vorderen (f), der linken (ls) und rechten (rs) und der hinteren (r) Stangenabschnitte oder Stababschnitte des ersten schleifenförmigen Heizstabs (15a') zumindest annähernd gleichmäßig von einem der Ofentür (13), der Seitenwände (11a, 11b) und der Rückwand (9) in einem ersten Abstand beabstandet ist, und

jeder der vorderen (f), der linken (ls) und rechten (rs) und der hinteren (r) Stangenabschnitte oder Stababschnitte des zweiten schleifenförmigen Heizstabs (15b') zumindest annähernd gleichmäßig von einem der Ofentür (13), der Seitenwände (11a, 11b) und der Rückwand (9) in einem zweiten Abstand beabstandet ist.

8. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
die ersten und zweiten schleifenförmigen Heizstäbe (15a', 15b') oder Widerstandsheizer einzeln steuerbar sind.

9. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
der zweite schleifenförmige Heizstab (15b') oder Widerstandsheizer konzentrisch zu dem ersten schleifenförmigen Heizstab (15a') oder Widerstandsheizer angeordnet ist.

10. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
der zumindest im Wesentlichen rechteckige zweite Bereich die mittlere Zone eines horizontalen Querschnittsbereichs des Ofenfachs (3) bedeckt, wobei der zumindest im Wesentlichen rechteckige zweite Bereich einen Anteil von mindestens 30 %, insbesondere mindestens 35 %, genauer gesagt mindestens 40 % des horizontalen Querschnittsbereichs einrahmt.

11. Ofen (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass
der erste schleifenförmige Heizstab (15a') oder Widerstandsheizer mit einer elektrischen Leistung zwischen 0,5 und 1,1 kW, vorzugsweise zwischen 0,65 und 0,95 kW, stärker bevorzugt von etwa 0,8 kW, betreibbar ist und der zweite schleifenförmige Heizstab (15b') oder Widerstandsheizer mit einer elektrischen Leistung zwischen 0,9 und 1,7 kW, vorzugsweise zwischen 1,1 und 1,5 kW, stärker bevorzugt von etwa 1,3 kW, betreibbar ist.

12. Verfahren zum Betreiben eines Ofens (1), insbesondere eines Haushaltsbackofens, nach einem der vorhergehenden Ansprüche,
dadurch gekennzeichnet, dass
eine Steuereinheit des Ofens (1) das Heizelement (15') während eines Betriebsprogramms zur Lebensmittelzubereitung mit Oberhitze, insbesondere eines Betriebsprogramms zum Backen, Rösten, Braten, Frittieren und/oder Grillen, betreibt.

13. Verfahren nach Anspruch 12,
dadurch gekennzeichnet, dass
mindestens einer der ersten und der zweiten schleifenförmigen Heizstäbe (15a', 15b') oder Widerstandsheizer während des Betriebsprogramms zur Lebensmittelzubereitung mit Oberhitze betrieben wird, wobei vorzugsweise mindestens einer der ersten und der zweiten schleifenförmigen Heizstäbe (15a', 15b') oder Widerstandsheizer während eines Betriebsprogramms zum Backen, Rösten, Braten und/oder Frittieren mit Oberhitze betrieben wird und sowohl die ersten als auch die zweiten schleifenförmigen Heizstäbe (15a', 15b') oder Widerstandsheizer während eines Betriebsprogramm zum Grillen betrieben werden.

Revendications

1. Four (1), en particulier un four de cuisson ménager, comprenant

- un compartiment de four (3) délimité par une paroi de dessus, une paroi de dessous (7), une paroi arrière (9) et des parois latérales (11a, 11b),

- une porte de four (13) fermant le compartiment de four (3) au niveau d'une ouverture avant, et

- un élément chauffant (15') agencé sur un côté de dessus du compartiment de four (3), préférablement en parallèle à la paroi de dessus, pour la préparation d'aliments à chaleur de dessus, en particulier pour cuire, pour rôtir, pour faire cuire sur le gril, pour frire et/ou pour griller, l'élément chauffant (15') comprenant au moins une première tige chauffante en forme de boucle (15a') ou un premier dispositif de chauffage à résistance, en particulier de conception tubulaire, et une deuxième tige chauffante en forme de boucle (15b') ou un deuxième dispositif de chauffage à résistance, en particulier de conception tubulaire,

dans lequel chaque tige parmi la première tige chauffante en forme de boucle (15a') et la deuxième tige chauffante en forme de boucle (15b') est conçue en tant qu'une unité à boucle unique en forme de boucle essentiellement rectangulaire, la première tige chauffante en forme de boucle (15a') encadrant une première zone au moins essentiellement rectangulaire et la deuxième tige chauffante en forme de boucle (15b') encadrant une deuxième zone au moins essentiellement rectangulaire, la première zone au moins essentiellement rectangulaire étant plus grande que la deuxième zone au moins essentiellement rectangulaire et la deuxième zone au moins essentiellement rectangulaire étant préférablement maintenue exempte de sections ou de composants d'élément chauffant,

caractérisé en ce que

la première tige chauffante en forme de boucle (15a') ou le premier dispositif de chauffage à résistance peut fonctionner avec une puissance électrique ayant une valeur comprise entre 50 % et 80 %, préférablement comprise entre 55 % et 70 %, plus préférablement d'environ 60 %, relativement à la deuxième tige chauffante en forme de boucle (15b') ou au deuxième dispositif de chauffage à résistance.

2. Four (1) selon la revendication 1
caractérisé en ce que
la première tige chauffante en forme de boucle (15a') englobe la deuxième tige chauffante en forme de boucle (15b'), la première tige chauffante en forme de boucle (15a') et la deuxième tige chauffante en forme de boucle (15b') étant préférablement agencées dans le même plan.

3. Four (1) selon la revendications 1 ou la revendication 2,
caractérisé en ce que
la première tige chauffante en forme de boucle (15a') et la deuxième tige chauffante en forme de boucle (15b') sont des pièces géométriquement similaires.

4. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
la première tige chauffante en forme de boucle (15a') et la deuxième tige chauffante en forme de boucle (15b') sont en forme de rectangles à coins arrondis.

5. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
le compartiment de four (3) est de forme au moins approximativement cuboïde, comprenant préférablement des bords latéraux verticaux à coins arrondis.

6. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
chaque tige parmi la première tige chauffante en forme de boucle (15a') et la deuxième tige chauffante en forme de boucle (15b') comprend

- une portion de barre avant ou portion de tige (f) agencée au moins approximativement en parallèle à la porte de four (13),

- des portions de barre ou portions de tige gauche et droite (ls, rs) agencées au moins approximativement en parallèle aux parois latérales (11a, 11b) du compartiment de four (3), et

- au moins une portion de barre ou portion de barre tige (r) agencée au moins approximativement en parallèle à la paroi arrière (9) du compartiment de four (3).

7. Four (1) selon la revendication 6,
caractérisé en ce que

chacune des portions de barre ou portion de tige avant (f), gauche (ls) et droite (rs) et arrière (r) ou de la première tige chauffante en forme de boucle (15a') est au moins approximativement espacée de manière égale d'au moins un élément parmi la porte de four (13), les parois latérales (11a, 11b) et la paroi arrière (9) à une première distance, et

chacune des portions de barre avant (f), gauche (ls) et droite (rs) et arrière (r) de la deuxième tige chauffante en forme de boucle (15b') est au moins approximativement espacée de manière égale d'au moins un élément parmi la porte de four (13), les parois latérales (11a, 11b) et la paroi arrière (9) à une deuxième distance.

8. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
les première et deuxième tiges chauffantes en forme de boucle (15a', 15b') ou premier et deuxième dispositifs de chauffage à résistance peuvent être commandé(e)s individuellement.

9. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
la deuxième tige chauffante en forme de boucle (15b') ou le deuxième dispositif de chauffage à résistance est agencé(e) de manière concentrique par rapport à la première tige chauffante en forme de boucle (15a') ou au premier dispositif de chauffage à résistance.

10. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
la deuxième zone au moins essentiellement rectangulaire recouvre la zone centrale d'une zone de section transversale horizontale du compartiment de four (3), la deuxième zone au moins essentiellement rectangulaire encadrant un rapport d'au moins 30 %, en particulier d'au moins 35 %, plus particulièrement d'au moins 40 % de la zone de section transversale horizontale.

11. Four (1) selon l'une quelconque des revendications précédentes,
caractérisé en ce que
la première tige chauffante en forme de boucle (15a') ou le premier dispositif de chauffage à résistance peut fonctionner avec une puissance électrique comprise entre 0,5 et 1,1 kW, préférablement entre 0,65 et 0,95 kW, plus préférablement d'environ 0,8 kW, et la deuxième tige chauffante en forme de boucle (15b') ou le deuxième dispositif de chauffage à résistance peut fonctionner avec une puissance électrique comprise entre 0,9 et 1,7 kW, préférablement entre 1,1 et 1,5 kW, plus préférablement d'environ 1,3 kW.

12. Procédé de fonctionnement d'un four (1), en particulier un four de cuisson ménager, selon l'une quelconque des revendications précédentes,
caractérisé en ce que
une unité de commande du four (1) fait fonctionner l'élément chauffant (15') pendant un programme de fonctionnement de préparation d'aliments à chaleur de dessus, en particulier un programme de fonctionnement de cuisson, de rôtissage, de cuisson sur le gril, de friture et/ou de grillade.

13. Procédé selon la revendication 12,
caractérisé en ce que
au moins un élément parmi les première et deuxième tiges chauffante en forme de boucle (15a', 15b') ou les premier et deuxième dispositifs de chauffage à résistance est mis en fonctionnement pendant le programme de fonctionnement de préparation d'aliments à chaleur de dessus, préférablement au moins un élément parmi les première et deuxième tiges chauffantes en forme de boucle (15a', 15b') ou les premier et deuxième dispositifs de chauffage à résistance est mis en fonctionnement pendant un programme de fonctionnement de cuisson, de rôtissage, de cuisson sur le gril et/ou de friture à chaleur de dessus et les première et deuxième tiges chauffantes en forme de boucle (15a', 15b') ou les premier et deuxième dispositifs de chauffage à résistance sont mis en fonctionnement pendant un programme de fonctionnement de grillade.

Drawing