WO2015071802A1

WO2015071802A1 - Oven muffle comprising a magnetic gasket

Info

Publication number: WO2015071802A1
Application number: PCT/IB2014/065816
Authority: WO
Inventors: Fabio Gambardella; Matteo Scoponi
Original assignee: Indesit Company S.P.A.
Priority date: 2013-11-13
Filing date: 2014-11-05
Publication date: 2015-05-21
Also published as: ITTO20130917A1

Abstract

The invention relates to an oven gasket and an oven (100) for cooking foods, wherein said oven (100) comprises a muffle (1), in turn comprising a plurality of walls (2-6) circumscribing a cooking cavity, and an aperture (10) for accessing the cavity, which can be closed by a door of the oven, a perimetric edge (7,9) around said aperture (10), a door sealing gasket (8) applied along said perimetric edge (7,9) by means of a magnet (82).

Description

"OVEN MUFFLE COMPRISING A MAGNE TIC GASKE T"

DESCRIPTION

The present invention relates to an oven for cooking foods and to an oven gasket.

As is known, an oven for household use or anyway for cooking foods comprises a gasket positioned along its aperture, so that the oven door, when closed, stays in abutment with said gasket .

This gasket is useful for preventing the heated air within the oven from exiting, thus causing a reduction in the energetic efficiency of said oven.

When the oven is in operation, the different parts of the gasket reach very different temperatures; therefore, internal strains arise in said gasket due to different levels of thermal expansion.

These stresses increase even further when the oven is executing the so-called pyrolysis cycle, during which the internal temperature of the oven may reach, or even exceed, 550 °C.

In order to prevent the gasket from suffering damage, some ovens offer the possibility of removing the gasket from its seat. In fact, the gasket seat has a profile that is compatible with that of the gasket itself, thus ensuring a stable coupling between the two parts. This solution, however, has the drawback that the gasket might be damaged and/or break during removal due to excessive mechanical stress caused by excessive force exerted by an operator and/or by the gasket being caught in its seat, thus making it necessary to replace the gasket.

Moreover, near or on the external surface of the gasket dirt is often formed by deposits of solid particles contained in the fumes that are generated while food is being cooked.

Because of this dirt, the gasket and the surrounding area typically need to be cleaned at shorter intervals than required for the pyrolysis cycle, resulting in a higher probability of damage to said gasket. Even though the gasket is not removed from its seat while cleaning, it may however be damaged by a cleaning rag, since this type of cleaning requires that a strong pressure be applied with the cleaning rag against the muffle mouth, and hence against the gasket, which consequently will be subjected to a pulling force that will tend to lengthen it and might therefore damage it.

Another solution for fastening the gasket to the muffle consists of the use of a glue that keeps the gasket attached to the muffle. This solution has the drawback that the gasket cannot be removed from the muffle, unless new glue is used. Furthermore, while separating the gasket from the muffle it is very likely that the gasket will get irreversibly damaged, thus needing replacement.

It is one object of the present invention to overcome these drawbacks; in other words, to prevent the gasket from undergoing excessive stress during separation from the muffle. The basic idea of the present invention is to include at least one magnet within an oven gasket, so that the gasket can be fixed to the muffle by means of said magnet.

The features of the present invention will be specifically set out in the appended claims.

These features as well as further advantages of the present invention will become more apparent from the following description of an embodiment thereof as shown in the annexed drawings, which are supplied by way of non-limiting example, wherein :

Fig. 1 is a perspective view of a muffle of an oven according to the invention;

Fig. 2 is a front view of a part of the oven according to the invention, comprising the part of Fig. 1 coupled to a support frame ;

Fig. 3 is a view along section A-A of Fig. 2 ;

Fig. 4 is a view of the detail B of Fig. 3.

With reference to Figures 1 and 2, an oven 100 according to the invention comprises a muffle 1, which in turn comprises a pair of side walls 2,4, a back wall 3, a bottom 5, and a top wall 6, which delimit a cooking cavity or chamber having an aperture 10 towards the outside.

In addition, said oven 100 may also comprise a support frame 7 coupled to an edge 9 of said aperture 10, thus allowing said muffle 1 to be positioned and secured in a casing (not shown in the annexed drawings) or in a cavity of a kitchen cabinet (not shown in the drawings) .

For the purpose of allowing foods to be placed into the muffle 1, the frame 7 comprises an aperture that, when the frame is coupled to the edge 9, puts the inside of the cooking chamber of the muffle 1 in flow communication with the outside environment .

Furthermore, the size and shape of this aperture preferably are such that the edge 9 can be at least partially visible and/or reachable from outside the muffle, thus allowing an oven gasket to be positioned on said edge. In fact, the dimensions of the aperture delimited by the edge 9 are preferably smaller than those of the aperture of the support frame 7.

The support frame 7 is coupled to the edge 9 by means of fastening tabs 91,92,93, preferably arranged along the edge 9 and preferably obtained while pressing the walls 2-6, which cooperate with fastening means such as screws, rivets or the like .

The man skilled in the art may however use fastening means other than those described above, without however departing from the teachings of the present invention. Also with reference to Figures 3 and 4, the coupling between the edge 9 and the support frame 7 forms a seat 71 into which an oven gasket 8 can be positioned.

The seat 71 is formed by an inner part 71a and an outer part 71b, respectively consisting of the edge 9 and the support frame 7. These two parts 71a, 71b are spaced apart so as to create a cavity 72 that advantageously allows preventing the heat coming from within the muffle 1 from being transferred to the support frame 7.

The gasket 8 has an elongated shape and comprises a central part 81, which is preferably made of silicone and comprises a channel 811 in which at least one magnet 82 is positioned. The central part 81 and the magnet 82 can be obtained, for example, by co-extrusion.

The section of the central part 81 may have an internally hollow shape, preferably a tubular one, so that the channel 811 will completely surround or incorporate said magnet 82. In this manner, the magnet 82 will be protected against dirt caused by grease and vapour in the oven, and the gasket can advantageously be applied to the edge of the aperture 10.

As an alternative, the magnet may be set into the gasket, without being wholly contained within the central part 81. This magnet 82 generates a magnetic field that, since it is only minimally altered by the silicone around it, allows the gasket 8 to be kept in contact with the edge 9 of the muffle 1. In fact, the edge 9 is made of a material, preferably a metallic one, that interacts with said magnetic field generated by the magnet 82. The force generated by said magnet 82 is preferably equal to 0.24 N/m (24 g/m) .

As an alternative to or in combination with the above, it must be pointed out that the gasket 8 may also be coupled to a part of the frame 7. Generally speaking, the gasket 8 is applicable, by means of the magnet 82, to a perimetric edge around the aperture 10 of the muffle 1, wherein said perimetric edge comprises the edge 9 and/or the frame 7.

The magnet is made of a material, preferably iron or an alloy thereof, having a Curie temperature higher than the temperature that can be reached inside the muffle 1 during the normal operation of the oven (about 200-300 °C) , so as to ensure that the magnet 82 will always generate a substantially constant magnetic field. Moreover, the magnet 82 preferably has an elongated shape extending along the whole length of the gasket 8. Alternatively, a plurality of magnets 82 may be arranged along the gasket 8, preferably within the channel 811 of the central part 81, at more or less regular intervals, so as to advantageously allow bending the gasket 8 for transportation or cleaning purposes. Also, the presence of more than one magnet 82 within the gasket 8 allows the latter to be stably kept in a folded condition, thus facilitating transportation and/or storage thereof. In fact, the magnets 82, when close to each other, attract and repel each other, thus advantageously providing indications to a service technician about how said gasket 8 must be folded.

The gasket 8 is arranged along the entire edge 9, and may advantageously be formed by four independent sections, preferably prevalently straight ones, each of which is associated with one side of the edge 9, thereby advantageously facilitating the assembly and/or transportation operations. In fact, the straight sections allow one-hand removal and minimize the risk of damage, whereas a rectangular gasket 8 would require the use of both hands to avoid subjecting the gasket 8 to excessive stress that might break and/or damage it.

To ensure better sealing, the gasket 8 also comprises an external lip 83 extending mainly outwards from the muffle 1 and towards the centre of the aperture 10 of said muffle 1, i.e. said lip 83 protrudes from the central part 81.

In an operating condition, a door (not shown in the annexed drawings) is coupled to the muffle 1 by means of fastening cavities 73 located in the lower part of the support frame 7. When the door is closed, said door abuts against the external lip 83 of the gasket 8, thereby deforming it and improving the sealing effect. As a matter of fact, the presence of the magnet 82 within the channel 811 of the central part 81 makes the whole gasket 8 more rigid, reducing its sealing effect; the external lip 83 solves this problem by adding highly deformable material (e.g. silicone or the like) in front of the central part 81, so as to avoid any direct contact between the oven door and said central part 81.

The gasket 8 also comprises an internal lip 84 that preferably extends towards the cavity 72, i.e. in the direction opposite to the external lip 83, so as to advantageously allow the gasket 8 to be properly positioned.

In addition, said internal lip 84 advantageously allows obstructing said cavity 72, thus preventing dirt from accumulating into said cavity 72.

In a first variant, the seat 71 can be obtained by moulding, along the edge 9, a cavity (not shown in the annexed drawings) having dimensions suitable for housing the gasket 8, thus advantageously making the seat 71 independent of the support frame 7. In a second variant, the seat 71 may solely consist of the edge 9, because a gasket (not shown in the annexed drawings), similar to the gasket 8 employed in the above- described embodiments, may be so shaped as to fit the shape of the edge 9.

Of course, the example described herein may be subject to further variations, which will nonetheless still fall within the scope of the following claims.

Claims

1. Oven (100) suitable for cooking foods, comprising

- a muffle (1), in turn comprising a plurality of walls (2-6) circumscribing a cooking cavity, and an aperture (10) for accessing the cavity, which can be closed by a door of the oven,

- a perimetric edge (7,9) around said aperture (10),

- a door sealing gasket (8), applied along said perimetric edge (7,9) ,

characterized in that

the gasket (8) is associated with at least one magnet (82) that keeps it applied to the perimetric edge (7,9) .

2. Oven (100) according to claim 1, wherein the gasket (8) comprises a central part (81) comprising a channel (811) in which said at least one magnet (82) is positioned.

3. Oven (100) according to claim 2, wherein the central part (81) has a tubular cross-section that surrounds or fully incorporates said magnet (82) .

4. Oven (100) according to claim 2 or 3, wherein the gasket (8) comprises an external lip (83) that protrudes from the central part (81), wherein said external lip (83) is so configured as to abut against the door of the oven.

5. Oven (100) according to any one of claims 1 to 4, wherein two or more magnets (82) are arranged along the gasket (8) .

6. Oven (100) according to any one of claims 1 to 5, wherein the magnet (82) has an elongated shape extending along the entire length of the gasket (8) .

7. Oven (100) according to any one of claims 1 to 6, wherein the perimetric edge (7,9) comprises a support frame (7) coupled to the muffle (1) .

8. Oven (100) according to any one of claims 1 to 7, wherein the perimetric edge (7,9) comprises an edge (9) delimiting the aperture (10) of the muffle (1) .

9. Oven (100) according to claims 7 and 8, wherein the support frame (7) is coupled to the edge (9) of the aperture (10) in such a way as to form a seat (71) for housing the gasket ( 8 ) .

10. Oven (100) according to claim 8 or 9, wherein the gasket (8) comprises four independent sections, each one of which is associated with one side of the edge (9) .

11. Oven (100) according to any one of claims 8 to 10, wherein the edge (9) of the aperture (10) comprises a slot in which the oven gasket (8) can be positioned.

12. Oven (100) according to any one of claims 8 to 11, wherein the gasket (8) is so shaped as to adapt itself to the shape of the edge (9) of the aperture (10) .

13. Oven (100) according to any one of the preceding claims, wherein the magnet (82) is made of iron or an alloy thereof having a Curie temperature higher than the temperature which will be reached in said muffle (1) .

14. Oven (100) according to any one of the preceding claims, wherein the external part of the gasket (8) is at least partly made of silicone.

15. Oven gasket (8) which can be positioned along a perimetric edge (7,9) that surrounds an aperture (10) of a muffle (1), wherein said muffle (1) is comprised in an oven

(100) according to any one of claims 1 to 14,

characterized in that

it comprises at least one magnet (82) capable of keeping said gasket (8) in contact with the perimetric edge (7,9) .