[0001] The present invention refers to a kitchen oven with an air cooled closing door.
[0002] Kitchen ovens are known to have closing doors provided with parallel glass panes
in order to form at least one gap through which air flows, and the continuous removal
of said air during oven operation makes it possible to avoid heating of the external
glass pane, so that users may not inadvertently get burned during oven operation when
coming into contact with the external glass pane.
[0003] For this purpose fans are used, which generate an air flow which is tangential to
the glass panes, in order to remove the air flowing out at the upper side of the gap.
Ovens of this type are known, e.g., from
US 5,918,589 and
EP 0 900 984 A1, respectively. Another prior art oven is known from
FR 2 655 132 A1.
[0004] Document
US 5 918 589 discloses the preamble of claim 1.
[0005] Generally, the fan is placed on the inside of the oven and generates an air flow
perpendicular to the plane of the door, when the door is closed. Such an air flow
typically passes through a generally horizontal conduit with an outlet section positioned
at the top of the gap.
[0006] The air flow generated by the fan passes along the upper end of said door in order
to generate an a depression which draws a certain flow of air to pass through the
same gap in a upwards direction.
[0007] Naturally, in this case, the gap communicates with the outside through a lower air
inlet opening.
[0008] However, such ovens of the prior art, even if avoiding excessive heating of the outermost
glass pane of the door, do not always avoid reaching temperatures, measured on the
external glass pane of the door, sufficient to cause a slight contact burn.
[0009] This drawback occurs primarily when the oven operates at its maximum temperature
for a long period of time.
[0010] Therefore, there is a need for an oven with an air cooled door which guarantees a
more efficient and faster air replacement in the door gap, where, at the same time,
the oven maintains a relatively low temperature, in order to avoid any type of burning
to the user who touches the external face of the external pane of the door, during
normal oven operation, using a simple and rational construction.
[0011] The object of the present invention consists in providing an oven with an air cooled
door, having structural and functional characteristics which meet the above said need,
to overcome functional and constructional disadvantages of the prior art and to offer
an oven with a more simple and more cost effective construction.
[0012] This object is achieved by an oven with an air cooled door according to claim 1.
[0013] The dependent claims comprise preferred and especially advantageous embodiments of
the oven according to the invention.
[0014] Further characteristics and advantages of the invention will become apparent from
the following description, which is intended to be only illustrative and non limitative,
in connection with the attached figures, in which:
Fig. 1 shows a front view of an oven according to the present invention,
Fig. 2 shows a view along line II-II of fig. 1,
Fig. 3 shows a view along line III-III of fig. 1,
Fig. 4 shows part of a view along line IV-IV of fig. 1,
Fig. 5 and 6 show a respective enlarged detail of fig. 2.
[0015] With reference to figs. 1-3, 1 generally indicates an oven according to the present
invention.
[0016] In the example shown, the oven 1 is a built-in oven mounted inside a cupboard.
[0017] As can easily be seen in fig. 2, the oven 1 comprises, generally, a support structure
which defines a cooking chamber 2, known as a muffle, provided with an opening on
one side, for accessing a cooking cavity 3 inside, a door 4 for closing the chamber
2, means for moving air, which will be described in greater detail later, and means
for heating the inside of the cavity 3.
[0018] In particular the closing door 4 is hinged by means of two invisible struts to the
chamber 2, so that it can be rotated between a closed position, in which the door
4 is disposed in a substantially vertical plane in order to close the opening and
avoid access to the cavity 3, and an open position in which said door 4 is, for instance,
inclined with respect to the vertical plane, in order to allow access to the cooking
cavity 3 through said opening.
[0019] In the example shown, the means for heating the inside of the cavity 3 comprise a
pair of electric resistors 10, one of which is placed inside the cavity 3 near the
upper wall and the other is positioned in a slot 11 adjacent to the lower wall of
chamber 2.
[0020] The air moving means comprise a blower 5, mounted above chamber 2, and positioned
on the side opposite to where the door 4 is mounted, in order to generate an air flow
perpendicular to the plane of door 4 when in the closed position.
[0021] In particular, the blower 5 communicates with a suction duct 6, through which a first
air flow is drawn, in a way which will be described later, and with an expulsion duct
7, through which said first air flow, drawn through the suction duct 6, is expelled.
[0022] The suction duct 6 and the expulsion duct 7 are overlapping and separated by a common
separation wall 67 and are formed by a respective flared conduit, which is substantially
horizontal.
[0023] In particular, the conduit in the suction duct 6 has an inlet section 6a, positioned
above the opening of chamber 2 and which preferably spans the whole width of door
4. The conduit of expulsion duct 7 has an outlet section 7a positioned above the inlet
section 6a of the suction duct 6 and preferably spans the whole width of door 4.
[0024] The cross-section of the suction duct 6 increases starting from the inlet section
6a, towards the bottom where the blower 5 is positioned, whereas the cross-section
of expulsion duct 7, in the upper position, decreases starting from blower 5 up to
the outlet section 7a.
[0025] In the example shown, the cross-section measured at the inlet section 6a is smaller
than the outlet cross-section 7a.
[0026] According to the present invention, the door 4 comprises an external plate 41, an
internal plate 42 and two further plate-like elements, reference numeral 43, all of
which are opposed and parallel to each other in order to form three gaps, wherein
the outermost is indicated by 51 and the other two internal gaps are indicated by
52 and 53.
[0027] The plates 41, 42 and the plate-like elements 43 are held together to form the door
4, by a support frame comprising a pair of lateral struts 8 formed by a hollow profile.
On each strut 8 a shaped element is attached, in order to form guiding channels 8a
(fig. 4) in which the plate-like elements 43 may slide.
[0028] In particular, the guiding channels 8a are formed in a direction generally parallel
to the longitudinal extension of struts 8.
[0029] Plates 41 and 42 are mounted on two opposed faces of the struts 8. In particular,
the outermost plate 41 is supported on the lower side by a pair of small brackets
12 (fig. 6) which are fixed to the lower ends of the two struts 8 by means of screws,
whereas the innermost plate 42 is supported by a profile 9 (fig. 6), which is laterally
fixed to the two brackets 12 by means of screws.
[0030] The two brackets 12 isolate the outermost plate 41 from the two struts, avoiding
direct heat transfer between the strut and the respective plate.
[0031] The profile 9 has three seats 9a at its ends for holding the lower edges of the innermost
plate 42 and the edges of the two plate-like elements 43.
[0032] On the external face of the outermost plate 41 a gripping handle 50 is attached,
which extends along the whole width of door 4 near its upper edge.
[0033] According to the present invention, the supporting frame of the door 4 further comprises
a terminal body 20 (fig. 5) associated to the two struts 8, and positioned along the
upper edge of door 4.
[0034] In particular, said body 20 has a first portion 21 which forms a deflector which,
when the door is in its closed position, forms an extension of the separating wall
67 of the two ducts 6 and 7, reducing the flow section for the air flow blown to the
outside through the expulsion duct 7, and a second separating portion 22, which separates
and seals off the two innermost gaps 52 from the outermost gap 51.
[0035] More in particular, the deflector 21, when the door 4 is in its closed position,
forms a passageway 70 with a variable cross-section, which decreases towards the direction
of expulsion of the air flow; the deflector forms a sort of terminal opening for the
expulsion duct 7 with an overhanging horizontal portion 23 of the oven supporting
structure.
[0036] Effectively, the air flow through the expulsion duct 7 is forced to pass through
a further narrowing 70 before being completely expelled.
[0037] The second separating portion 22 is formed by a flat profile integral with the deflector
21, which is inserted into the central gap 53, directly contacting the outermost plate-like
element 43 along its whole width, inhibiting the flow of air from the innermost gaps
52, 53 towards the outermost one 51.
[0038] Obviously, said second portion 22 may be put into contact with the outermost face,
as long as it ensures a seal which inhibits the air from flowing from the two innermost
gaps 52, 53 towards the outermost gap 51 and vice versa.
[0039] The fixing of the terminal body 20 to the struts 8 is obtained by interposing the
two lateral blocking portions 24, associated to the free ends of the body 20, which
are shaped in such a way as to cooperate with the terminal body 20 and the two struts
8.
[0040] In particular, teeth 25 protrude from each lateral blocking portion 24, which correspond
to the gaps 51, 52, 53.
[0041] According to the present invention, the two innermost gaps 52, 53 isolated from the
outermost gap 51, communicate with the suction duct 6, whose inlet section 6a is aligned
to the upper edge of the innermost plate 42 and to the innermost plate-like element
43 when the door 4 is in its closed position.
[0042] In particular, the lower wall of the suction duct 6 is horizontally positioned at
a height such that it is aligned to the upper edge of the innermost plate 42, when
the door 4 is closed.
[0043] In this example, the edge of the innermost plate-like element 43 reaches a level
lower than that of the innermost plate 42, whereas the rest of the outermost plate-like
element 43 reaches a height greater than the one reached by the innermost plate 42.
[0044] The outermost gap 51, when the door 4 is in its closed position, is connected to
the expulsion duct 7 at the narrowing 70.
[0045] In particular, the outermost gap 51 opens at the top directly behind the deflector
21 of the terminal body 20, with respect to the flow direction.
[0046] Obviously, all gaps 51, 52, 53 are connected to the outside through an opening which
preferably spans the whole width of the door 4, which is left free at the lower edge
of the same door 4.
[0047] Regarding operation, when the oven 1 is switched on, the blower 5, whose rotational
axis is horizontal and parallel to the plane of door 4, draws a first air flow to
rise through the two innermost gaps 52, 53, via the suction duct 6, which is connected
only to the two gaps 52, 53.
[0048] Said first air flow is immediately expelled by the same blower 5, through the expulsion
duct 7, which is positioned above the suction duct 6. Before leaving the oven 1, said
first air flow passes through the narrowing 70, which lies directly behind the expulsion
duct 7.
[0049] The first horizontal air flow, due to a Venturi effect, draws a second air flow upwards,
which rises through the outermost gap 51, at the narrowing 70 formed by the deflector
21, and finally leaves the oven, as shown by the arrows in fig. 5.
[0050] In other words, at the narrowing 70 a sort of suction effect is applied to the second
air flow which, therefore, is drawn together with the first air flow exiting from
the expulsion duct 7, immediately after the latter has left the outermost gap 51 at
its upper side.
[0051] In this way, the rate at which hot air is replaced in the outermost gap 51, i.e.
the one adjacent to the outermost plate 41, is extremely high, so that excessive heating
of the outermost plate 41 is avoided.
[0052] According to a preferred embodiment of the present invention, the oven 1 is provided
with a chimney 80 for extracting exhaust gases from the cooking chamber 2, which is
connected to the expulsion duct 7.
[0053] Moreover, the blower 5 is connected to a shirt 90 adjacent to the back of the chamber
2, in which a motor 91 for a common radial ventilator 92 is provided, in order to
generate a replacement of air inside the shirt 90 as well.
[0054] Further air inlets, communicating with the blower 5, are provided underneath and
on the sides of the oven.
[0055] In the present description, all the definitions regarding spatial positions of elements
forming the door 4 refer to the door 4 in its closed position, i.e. in a generally
vertical position.
[0056] Although reference has been explicitly made to a door 4 having three gaps 51, 52,
53 it is possible to provide a door 4 with any number of gaps separated by plate-like
elements, as long as the innermost gaps are isolated from the outermost gap and are
connected to the suction duct 6.
[0057] In its simplest form, not illustrated, the door 4 may comprise only two gaps, connected
to the suction duct 6 and narrowing 70, respectively.
[0058] As can be appreciated by the above description, the oven with an air cooled door
according to the present invention meets the requirements and overcomes the disadvantages
referenced in the introduction of the present invention, with reference to the prior
art.
[0059] In fact, the oven according to the present invention allows a continuous replacement
of the hot air which is in direct contact with the outermost glass pane of door 4,
maintaining a suitable temperature and ensuring the thermal security requirements
for users.
[0060] Obviously, those skilled in the art will readily introduce various modifications
and variants to the described oven with air cooled door, in order to meet any contingent
and specific need, which by the way are all comprised inside the protection scope
of the invention, as defined in the following claims.
1. An oven (1) comprising an air cooled door (4), movable from a closed position, inhibiting
access to the oven cooking chamber (2), to an open position, allowing access to the
chamber (2), wherein said door (4) comprises a first outermost gap (51) and a second
innermost gap (52), which are positioned on the outer and inner side of the door (4),
respectively, when the door (4) is in its closed position, wherein the door (4) comprises
an external plate and an internal plate, whereby when the oven is operating and the door (4) is in its
closed position, air moving means (5) draw a first air flow, rising through said second
gap (52), through a suction duct (6), and blow it to the outside, through an expulsion
duct (7), wherein through said first gap (51) a second air flow rises, not being able
to pass through said suction duct (6), wherein said second air flow encounters said
first air flow exiting from the expulsion duct (7), immediately after having left
the first gap (51), at a narrowing (70), which is formed by a deflector (21), when
the door (4) is in its closed position, said first gap (51) being connected to the
expulsion duct (7) at the narrowing (70),
characterized in that said door (4) further comprises a central gap (53) and two further plate-like elements,
the external plate, the internal plate and the two further plate-like elements being
opposed and parallel to each other in order to form said three gaps, and a terminal
body (20), said terminal body (20) having a first portion (21) which forms a deflector
and a second separating portion (22) associated to the door (4), which separates said
second gap (52) from said first gap (51), so that the second air flow cannot be drawn
through the suction duct, whereby said deflector (21) is associated to said door (4),
and said separating portion (22) is formed by a flat profile integral with said deflector
(21), which separating portion is inserted into the central gap (53), directly contacting
the outermost plate-like element (43) along its whole width, inhibiting the flow of
air from the innermost gap (52) to the outermost gap (51), said terminal body (20)
being positioned along the upper edge of the door (4).
2. Oven according to claim 1, wherein said deflector (.21) forms an extension of the
expulsion duct (7), and is located downstream with respect to the direction of flow.
3. Oven according to claims 1 or 2, wherein said deflector (21) is positioned above said
second gap (52), and is fixed to two lateral supporting struts (8) of the door (4).
4. Oven according to any of the preceding claims, wherein said suction duct (6) and said
expulsion duct (7) are generally horizontal and have an inlet section (6a) and an
outlet section (7a) positioned in the upper area of said gaps (51, 52).
5. Oven according to any of the preceding claims, in which said suction (6) and expulsion
(7) ducts are overlapping, wherein the expulsion duct is in the upper position, and
both are separated by a common separating wall (67), and are formed by a respective
flared conduit.
6. Oven according to any of the preceding claims, wherein said air moving means comprise
a blower (5), which is mounted above the chamber (2) and is positioned on the side
opposed to the side where the door (4) is mounted, in order to generate an air flow
which is perpendicular to the plane of the door (4), in its closed position.
1. Backofen (1), der eine luftgekühlte Tür (4) aufweist, die sich aus einer geschlossenen
Position, die den Zugang zum Kochraum (2) des Backofens verhindert, in eine offene
Position, die den Zugang zum Kochraum (2) erlaubt, bewegen lässt, wobei besagte Tür
(4) einen ersten äußeren Zwischenraum (51) und einen zweiten inneren Zwischenraum
(52) aufweist, die sich auf der äußeren bzw. auf der inneren Seite der Tür (4) befinden,
wenn die Tür (4) in ihrer geschlossenen Position ist, wobei die Tür (4) eine äußere
Platte und eine innere Platte beinhaltet, wodurch, wenn der Ofen in Betrieb und die
Tür (4) in ihrer geschlossenen Position ist, Luftförder-Vorrichtungen (5) einen ersten
Luftstrom, der durch besagten zweiten Zwischenraum (52) aufsteigt, durch einen Saugkanal
(6) ansaugen und ihn durch einen Ausstoßkanal (7) nach außen blasen, wobei durch besagten
ersten Zwischenraum (51) ein zweiter Luftstrom aufsteigt, der nicht durch besagten
Saugkanal (6) hindurchströmen kann, wobei besagter zweiter Luftstrom auf besagten
ersten Luftstrom, der aus dem Ausstoßkanal (7) herauskommt, trifft, unmittelbar nachdem
er den ersten Zwischenraum (51) an einer Engstelle (70) verlassen hat, die durch einen
Deflektor (21) gebildet wird, wenn die Tür (4) sich in ihrer geschlossenen Position
befindet, wobei besagter erster Zwischenraum (51) mit dem Ausstoßkanal (7) an der
Engstelle (70) verbunden ist, verlassen hat,
dadurch gekennzeichnet, dass besagte Tür (4) ferner einen zentralen Zwischenraum (53) und zwei weitere plattenförmige
Elemente aufweist, wobei die äußere Platte, die innere Platte und die beiden weiteren
plattenförmigen Elemente einander gegenüber und parallel zueinander angeordnet sind,
um besagte drei Zwischenräume zu bilden, und ein Abschlussgehäuse (20), wobei besagtes
Abschlussgehäuse (20) einen ersten Teil (21), der einen Deflektor bildet, und einen
zweiten, mit der Tür (4) verbundenen Abstandsteil (22), der besagten zweiten Zwischenraum
(52) vom ersten Zwischenraum (51) trennt, aufweist, so dass der zweite Luftstrom nicht
durch den Saugkanal gesogen werden kann, wobei besagter Deflektor (21) mit besagter
Tür (4) verbunden ist, und besagter Abstandsteil (22) durch ein flaches Profil gebildet
ist, das mit besagtem Deflektor (21) ein integrales Bauteil bildet, dessen Abstandsteil
in den zentralen Zwischenraum (53) hineingesteckt ist, wobei er das äußere plattenförmige
Elemente (43) entlang seiner vollen Breite direkt berührt und damit das Strömen von
Luft vom inneren Zwischenraum (52) zum äußeren Zwischenraum (51) verhindert, wobei
besagtes Abschlussgehäuse (20) entlang der oberen Kante der Tür (4) angeordnet ist.
2. Backofen nach Anspruch 1, wobei besagter Deflektor (21) eine Verlängerung des Ausstoßkanals
(7) bildet und stromabwärts bezogen auf die Strömungsrichtung angeordnet ist.
3. Backofen nach Anspruch 1 oder 2, wobei besagter Deflektor (21) oberhalb besagtem zweiten
Zwischenraum (52) angeordnet und an zwei seitlichen Stützstreben (8) der Tür (4) befestigt
ist.
4. Backofen nach einem der vorangehenden Ansprüche, wobei besagter Saugkanal (6) und
besagter Ausstoßkanal (7) normalerweise horizontal sind und einen Einlassbereich (6a)
und einen Auslassbereich (7a) aufweisen, die im oberen Bereich besagter Zwischenräume
(51, 52) angeordnet sind.
5. Backofen nach einem der vorangehenden Ansprüche, bei dem besagter Saugkanal (6) und
besagter Ausstoßkanal (7) einander überlappen, wobei der Ausstoßkanal in der oberen
Position ist und beide durch eine gemeinsame Trennwand (67) getrennt sind und jeweils
durch einen sich weitenden Kanal gebildet werden.
6. Backofen nach einem der vorangehenden Ansprüche, wobei besagte Luftförder-Vorrichtungen
ein Gebläse (5) beinhaltet, das oberhalb des Kochraums (2) montiert und an der Seite
gegenüber der Seite, wo die Tür (4) montiert ist, angeordnet ist, um einen Luftstrom
zu erzeugen, der senkrecht zur Ebene der Tür (4) in ihrer geschlossenen Position ist.
1. Four (1) comprenant une porte refroidie à l'air (4), pouvant être déplacée d'une position
fermée, empêchant l'accès à la chambre de cuisson de four (2), à une position ouverte,
permettant l'accès à la chambre (2), dans lequel ladite porte (4) comprend un premier
espace le plus à l'extérieur (51) et un deuxième espace le plus à l'intérieur (52),
qui sont positionnés sur le côté extérieur et le côté intérieur de la porte (4), respectivement,
lorsque la porte (4) est en position fermée, dans lequel la porte (4) comprend une
plaque externe et une plaque interne, grâce à quoi lorsque le four fonctionne et que
la porte (4) est en position fermée, des moyens de déplacement d'air (5) prélèvent
un premier écoulement d'air, s'élevant à travers ledit deuxième espace (52), à travers
une gaine d'aspiration (6), et le soufflent vers l'extérieur, à travers une gaine
d'expulsion (7), dans lequel à travers ledit premier espace (51), un deuxième écoulement
d'air s'élève, n'étant pas en mesure de passer à travers ladite gaine d'aspiration
(6), dans lequel ledit deuxième écoulement d'air rencontre le premier écoulement d'air
sortant de la gaine d'expulsion (7), immédiatement après avoir quitté le premier espace
(51), au niveau d'un rétrécissement (70), qui est formé par un déflecteur (21), lorsque
la porte (4) est en position fermée, ledit premier espace (51) étant raccordé à la
gaine d'expulsion (7) au niveau du rétrécissement (70),
caractérisé en ce que ladite porte (4) comprend en outre un espace central (53) et deux éléments supplémentaires
semblables à des plaques, la plaque externe, la plaque interne et les deux éléments
supplémentaires semblables à des plaques étant opposés et parallèles les uns aux autres
pour former lesdits trois espaces, et un corps terminal (20), ledit corps terminal
(20) présentant une première portion (21) qui forme un déflecteur et une deuxième
portion de séparation (22) associée à la porte (4), qui sépare ledit deuxième espace
(52) dudit premier espace (51), de sorte que le deuxième écoulement d'air ne peut
pas être prélevé à travers la gaine d'aspiration, ledit déflecteur (21) étant associé
à ladite porte (4), et ladite portion de séparation (22) est formée par un profilé
plat intégré audit déflecteur (21), laquelle la portion de séparation est insérée
dans l'espace central (53), entrant directement en contact avec l'élément semblable
à une plaque le plus à l'extérieur (43) le long de l'ensemble de sa largeur, empêchant
l'écoulement d'air de l'espace le plus à l'intérieur (52) vers l'espace le plus à
l'extérieur (51), ledit corps terminal (20) étant positionné le long du bord supérieur
de la porte (4).
2. Four selon la revendication 1, dans lequel ledit déflecteur (21) forme une extension
de la gaine d'expulsion (7), et est situé en aval par rapport à la direction d'écoulement.
3. Four selon les revendications 1 ou 2, dans lequel ledit déflecteur (21) est situé
au-dessus dudit deuxième espace (52), et est fixé sur deux entretoises de support
latérales (8) de la porte (4).
4. Four selon l'une quelconque des revendications précédentes, dans lequel ladite gaine
d'aspiration (6) et ladite gaine d'expulsion (7) sont généralement horizontales et
présentent une section d'entrée (6a) et une section de sortie (7a) positionnées dans
la zone supérieure desdits espaces (51, 52).
5. Four selon l'une quelconque des revendications précédentes, dans lequel lesdites gaines
d'aspiration (6) et d'expulsion (7) se superposent, dans lequel la gaine d'expulsion
est dans la position supérieure, et les deux gaines sont séparées par une paroi de
séparation commune (67), et sont formées par un conduit évasé respectif.
6. Four selon l'une quelconque des revendications précédentes, dans lequel lesdits moyens
de déplacement d'air comprennent une turbine de ventilation (5), qui est installé
au-dessus de la chambre (2) et est positionné sur le côté opposé au côté où la porte
(4) est installée, afin de générer un écoulement d'air qui est perpendiculaire au
plan de la porte (4) en position fermée.