EP2330356A1 - Door seal strip and cooking device - Google Patents

Abstract

The strip (30) has two sealing surfaces (35) for sealing against a cooking chamber flange (10) and cooking chamber door, where the strip is made of temperature-resistant plastic material. An orifice is provided between the sealing surfaces and connected with an aperture (38), which allows vapor- and/or liquid passage in a transverse direction by the strip. A core strand (34) i.e. fabric tube, is made from a heat-resistant fiber material and solid material, and the passage is realized by penetration of the core strand. A sealing body (32) includes a sealing lip with one of the sealing surfaces.

Description

The invention relates to a door sealing strip of a cooking appliance according to the preamble of claim 1 and a cooking appliance according to the preamble of claim 10.

Door sealing strands are well known and are used to seal the cooking chamber of the cooking appliance against the environment or more specifically the cooking chamber flange of the oven muff against the cooking chamber door.

A cooking appliance may for example be an oven, a stove, a grill or a microwave oven, in particular such a device with pyrolytic self-cleaning function.

It is an essential task of modern cooking appliances to work energy efficiently. In particular, this means that the seal between the cooking chamber flange and cooking chamber door should close as tightly as possible, so that as little air exchange with the environment as possible can occur and that a corresponding energy loss is thus minimized. Here, simple silicone seals are known. Out EP 0 900 984 A1 Furthermore, a furnace with a pyrolytic self-cleaning with a seal of glass silk is known. Glass silk is extremely temperature resistant and inexpensive to produce. However, due to lack of elasticity, it can not adequately bridge and seal gaps of unequal width flexibly and over the life of the cooking appliance.

Out DE 101 56 778 A1 It is known to partially encase a glass fiber core strand with a silicone material, so that only the core strand, but not the shell material rests as a sealing material on particularly hot Gargerätebereichen.

Cooking device seals made of silicone, which reliably seal the gap from the cooking chamber flange to the cooking chamber door, have the problem that condensate can accumulate in the lower region of the gap and above the seal, do not run out of it and run uncoordinated when opening the oven door and surge out of the device can. This can be dirty attachment furniture or the floor. It is not an acceptable solution to the problem, for example, to leave in the longitudinal direction a gap or interruption in the seal for the drainage of the condensate, since this would take place an inadmissibly large heat flow. Also, the is off EP 0 900 984 A1 known effect that Garkondensat can penetrate the glass silk after some time, no solution of Problems, since, as already described, the sealing function of glass fiber is not sufficient.

According to the invention, a door sealing strip of a cooking appliance is provided for sealing between a cooking chamber flange and a cooking chamber door, wherein a first sealing surface for sealing against the cooking chamber flange and a second sealing surface for sealing against the cooking chamber door are provided from a temperature-resistant plastic. In this case, a passage is provided between the first sealing surface and the second sealing surface, which in particular has a plastic-free region and which allows a vapor and / or liquid passage in the transverse direction through the door sealing strand. Due to the possibility of liquid passage, a drainage of the condensate (vapor) is possible and thus prevents accumulation above the seal, which thus can not pour out like a gush when opening the door. By the described features a functional separation of the sealing function of the seal and the liquid passage is achieved. Each of the subfunctions can thus be optimized separately for themselves. Thus, the size of the passage and in particular (as will be described later) the passage through the fiber material of a core strand can be construed deliberately constructive, and on the other hand, the seal with its sealing surfaces are optimized for optimal sealing effect. If, on the other hand, a liquid passage would be made possible on the sealing surface, the sealing effect would depend on the surface finish of the opposite side, ie the cooking appliance flange or the cooking chamber door, which can hardly be designed constructively.

Advantageously, the door sealing strip has a core strand of a heat-resistant fiber material and the passage of steam and / or liquid is realized by penetrating the core strand. An advantage of the core strand is to increase the mechanical strength and bending stiffness of the door seal. In addition, the material costs of a heat-resistant plastic material, such as silicone, are significantly higher than a glass fiber or glass fiber material of the core strand, so that costs can be reduced by the choice of materials. In addition, liquid can penetrate the fiber material of the core strand to a defined extent and the fiber material is still a limitation of the free air exchange of the cooking chamber with the outside environment.

In addition, the sealing body may comprise a sealing lip with the first sealing surface for sealing against the cooking chamber door and also a guide surface for guiding condensed and draining liquid to the cooking chamber door to the passage. Since i.d.R. The cooking chamber door is colder than the rest of the cooking chamber, condensate forms here, which is led via the guide surface directly to the passage, so that accumulations of condensate are increasingly reduced.

In a further embodiment of the invention, a plurality of passages are provided, which extend in particular in the axial direction of the door seal. In this way, on the one hand, a large number of regions of the penetration of the door sealing strip can be produced, on the other hand, the door sealing strand can be manufactured in a continuous process as a semi-finished product without having to be adapted to a special cooking device during its production.

Next, the core strand is designed as a fabric tube with a hollow chamber. The hollow chamber increases the deformability of the core strand in the radial direction and ensures that the sealing surfaces can create as uniform a pressure as possible, even with uneven gap distances from the cooking chamber flange to the cooking chamber door on corresponding surfaces.

Alternatively, the core strand is designed as a solid material. A core strand made of solid material has a significantly higher strength and rigidity and if the door sealing strip only at some places on the cooking chamber (or the Garraumtür) such. attached to the corners, the rigidity prevents sagging of the door weatherstrip.

In addition, the passage has two plastic-resistant regions which extend continuously in the longitudinal direction of the door seal strand and thus divide the plastic of the first and second sealing surfaces into two separate segments which are not connected to one another and are attached to the core strand. Since this results in an undercut-free structure in the axial direction, a corresponding door sealing strip, in particular in an extrusion process, can be produced well. Furthermore, the possibility of penetrating the core strand is thus made possible over the entire length of the door sealing strand. While in other embodiments of the invention in the region of the passage recesses in the surface arise, in which In this case, a continuous channel, which can be easily wiped, results.

Alternatively, the core strand is coated in a net-like structure with the temperature-resistant plastic, so that a large number of non-plastic-coated regions of the core strand result axially and radially circumferentially. This embodiment may be preferred for a door seal string having a circular cross section, so that attention must not be paid to the angular orientation during its installation. Since the size of the individual plastic-free areas is always smaller than the contact surface of the seal the corresponding opposite sides is ensured that at the sealing surfaces always a sufficient sealing effect is achieved.

Furthermore, door sealing strip is designed as a closed ring for circumferential sealing of the cooking chamber opening. Since all around a good sealing effect is to be achieved, a continuous ring is advantageous because so no front sides of a seal against each other and could arise at this point either a gap or a compression. The door weatherstrip can be manufactured by injection molding or as a continuous strand in an extrusion process. In the latter, the door sealing strip can be produced as a semi-finished product and not specifically for a special cooking appliance and then converted into a ring in an adhesive or plug-in process and subsequently installed.

Also, the door sealing strip may have a hollow chamber with radially arranged openings of the hollow chamber, which show the door seal strand installed in the direction of the cooking chamber and further radially arranged openings of the hollow chamber, which show the built-in door seal in the direction of the device exterior. In particular, no core strand is used. Radial openings for hollow sections are already known because they are needed to bring warming air out of the hollow section. Also, when closing the cooking chamber door, the seal deformed, so that therefore air must be able to leave the hollow profile. These known openings always show in known embodiments, however, only in one direction, so with appropriate installation of the seal either to the oven or to the outside. This conventionally preferred arrangement resulted from the fact that the sealing effect would be reduced if openings were provided in two directions. However, it was recognized that through above-described openings on both sides of the sealing effect against heat dissipation is only slightly deteriorated, but the passage already described is made possible.

In the cooking appliance according to the invention, a corresponding door sealing strip is arranged at least partially on the lower sealing surface of the cooking chamber opening between cooking chamber flange and cooking chamber door. Preferably, a corresponding Türdichtungsstrang is used on the entire lower sealing surface. Since the condensate formed collects just in the lower area due to gravity, the described function of the door seal string is necessary here. Alternatively, the corresponding door sealing strip can also completely seal the cooking space flange circumferentially, and as a result, production costs can be saved by using only a single strand with a constant configuration in its axial direction.

Fig. 1:

eine Frontansicht des Gargeräts mit einer als Klappe ausgestalteten Garraumtür, welche geöffnet nach unten geklappt ist,

Fig. 2:

einen Teilquerschnitt längs der Ebene I - I der Fig.1,

Fig. 3:

einen entsprechenden Teilquerschnitt mit einem Abschnitt der Garraumtür,

Fig. 4 und Fig. 5

unterschiedliche Ausführungsformen des Strangs als 3D-Ausschnitt,

Fig. 6:

einen Schnitt durch den Türdichtungsstrang mit je einem oben und unten liegender Freimachung 38,

Fig. 7:

einen Schnitt eines Türdichtungsstrangs mit einer Dichtlippe,

Fig. 8:

einen Schnitt durch einen Türdichtungsstrang mit einer Darstellung eines Befestigungsprofils,

Fig. 9:

einen Schnitt durch einen weiteren Türdichtungsstrang mit Hohlkammer und ohne Kernstrang und

Fig. 10:

einen Abschnitt des Türdichtungsstrangs im Längsschnitt.

In the following, the invention will be described by way of example with reference to the drawings with reference to preferred embodiments. Show it:

Fig. 1:

a front view of the cooking appliance with a designed as a flap cooking chamber door, which is open when folded down,

Fig. 2:

a partial cross section along the plane I - I of Fig.1 .

3:

a corresponding partial cross-section with a portion of the cooking chamber door,

4 and FIG. 5

different embodiments of the strand as a 3D cutout,

Fig. 6:

a section through the door sealing strip, each with a top and bottom franking 38,

Fig. 7:

a section of a door seal with a sealing lip,

Fig. 8:

a section through a door sealing strip with a representation of a fastening profile,

Fig. 9:

a section through another door sealing strip with hollow chamber and without core strand and

Fig. 10:

a section of the door sealing strip in longitudinal section.

The cooking appliance 1 has a cooking chamber flange 10 and a cooking chamber door 20, with which a cooking chamber opening for charging the cooking chamber 5, which is formed in the Garraummuffel (oven), can be closed.

There is a door sealing strip 30 between the cooking chamber 10 and the cooking chamber door 20. The door sealing strip 30 may be in different ways either be attached to the cooking chamber 10 or the cooking chamber door 20 and seal against both parts. In the following, non-limiting exemplary embodiments, the door seal strip 30 is always fastened to the cooking chamber flange 10. Gluing is possible here, even if the high temperatures make special demands on the adhesive. The door sealing strip may comprise a sealing body with a hook profile or tooth profile 50 (FIG. Figure 8 ), which can be integrally formed as an extrusion profile on the length of the door sealing strip 30 or locally limited position and in openings or undercuts of the Garraumflansches 10 can be inserted and -rastbar.

Also can - like Fig. 6 shows - a holding profile 39 may be provided, such as a dovetail profile, in which an adapter (not shown) can be received, which can be plugged or snapped with the cooking chamber. The adapter is arranged in particular at the deflection radii of the door sealing strip at the corners of the cooking chamber flange, so as to predetermine the position of the door sealing strip exactly at these locations. In this case, the door seal is on the four longitudinal sides, ie the area between the Umlenkradien without an attachment to the Garraumflansch and held by an axial tension in its position.

It is an important task of the door sealing strip as close as possible to close the cooking chamber 5 against the environment, since any leak causes an exchange of air and thus energy loss, which reduces the efficiency of the cooking device 1. For this purpose, the door sealing strip according to Fig. 2 a core strand 34 made of a fiber material, preferably glass fiber, so extremely fine glass fibers, which gives the door seal a certain stiffness, without its ability to be guided along the curves of the corners of the cooking chamber, significantly obstruct. This core strand is coated on the sealing surfaces, so the contact surfaces to the cooking chamber 10 and the cooking chamber 20, with an elastic plastic. Since the fiber material of the core strand does not have sufficient elasticity or Anschmiegeigenschaft, it is less suitable for sealing tasks and therefore the plastic sheath is used accordingly.

Due to the high temperatures of the cooking chamber of over 200 ° C in normal operation and well above 300 ° C in the pyrolytic cleaning must be used according to temperature-resistant materials. As a core strand 34 is thus particularly suitable for a glass-fiber seal, which cost to finished and is also highly heat resistant. The diameter of the core strand is 5 mm. Also diameters in the range of 3 - 8 mm are commonly used. In the core strand metal cores are often braided or provided as a soul to increase the rigidity. The sealing body 32 is preferably made of silicone, which is a known heat resistant sealing material with good elasticity for good sealing properties. However, the seal body 32 may be formed of any other sufficiently heat-resistant and elastic plastics.

In each cooking appliance temperature profiles arise, often the door and in particular the gap between the cooking chamber 10 and the cooking chamber door 20 and between the seal to the cooking chamber, a low temperature, as the center of the cooking chamber. Also, often the inside of the cooking chamber door and in particular its glazing has a lower temperature than the rest of the cooking chamber. For foodstuffs with a high moisture content, condensate formation may occur at these cooler areas. This condensate 8, also called vapors, can in conventional sealing systems according to Fig. 3 accumulate above the door seal and leave the device when you open the oven door gushing and pour on add-on furniture, or the floor.

In order to avoid this effect, a clearance 38 is provided on the door sealing strip 30, which is functionally and spatially removed from the sealing surfaces at which the material of the core rod 34 is accessible to the outside. Here, the well-known effect is exploited that Garkondensat glass fiber can penetrate after some time.

Fig. 2 shows a core strand 34 of a solid material with a circular section. The core strand is in principle encased on all sides by a sealing body 32 made of a plastic. Fig. 2 shows passages 38 as openings in this seal body, which extend from the core strand up and down, but not to the left and right to the sealing surfaces 35 and 36. Condensate, which forms at the bottom sealing line from cooking chamber to cooking chamber above the door sealing strip, can reach the upper franking 38, there penetrate the core strand and will be derived by the lower clearance down. Below the cooking chamber flange is a trough 60, in which the condensate can drain or drain and collect there. Since a certain proportion of the heat of the cooking chamber is also emitted to the trough 60, the so elevated temperature ensures that the condensate evaporates from the tub and gaseous to the Outside or in the environment of the cooking appliance passes. Fig. 5 Fig. 3 shows how the clearances 38 in the door weatherstrip 30 are designed as round or oval jacket-free areas. Between the passages in each case a kind of web is provided as a connection of the material of the first to the second sealing surface, which gives the sheathing of the core strand a mechanical stability.

In the execution of the Fig. 2 and 5 it is essential that the passages 38 are oriented up and down to allow correspondingly the flow of condensate. Fig. 3 and 4 shows an alternative embodiment in which no solid material of the core strand 34, but this is a fabric tube is used, which has a hollow hollow chamber 45. The seal body 32 is according to Fig. 4 designed as a network structure, in which both in the longitudinal direction of the door seal strip 30, a plurality of clearances 38, as well as radially surrounding a plurality of corresponding clearances is provided. Fig. 3 shows on average four of these clearances 38. On the right side of the door seal is in a stamped in the sheet of Garraumflanschs and preferably circumferential recess, so that the sealing effect is generated by contact of two areas of the seal body to the cooking chamber 10. By pressing the cooking chamber door 20, the core strand deforms and the sealing body 32 comes with two areas in contact with the cooking chamber door 20. The steam and / or liquid passage is realized by the two above and below franking 38. An advantage of this embodiment is that no angular alignment of the door seal string 30 is necessary.

Fig. 6 shows an alternative of the door sealing strip in section with a retaining profile 39 which is clipped over a corresponding contact surface of the Garraumflansches 10, or via a corresponding adapter (not shown) can be attached to the cooking chamber. Here, the first sealing surface 35 and the second sealing surface 36 are marked with dashed lines.

In the variant of Fig. 6 the sealing body is divided into two parts. In this case, the franking 38 is not designed as a local plastic-free point or area, but as a non-continuous region running continuously in the longitudinal direction of the door sealing strip. This would be the appearance of the Fig. 5 correspond if the webs between the passages 38 were omitted. A corresponding profile is easy to produce in an extrusion process and the large surface of z. B. fiberglass material of the core strand ensures good mechanical adhesion of the two-part seal body to the core strand.

As in Fig. 7 is shown in a further variant on the sealing body 32, a sealing lip 42 is formed, which forms the first sealing surface 35 on the one hand. Even though the sealing lip only seals with a line (seen axially), in the sense of this patent it means a sealing surface. In addition, a guide surface 37 is provided on the sealing lip, which has such a tilt angle that condensate, which runs down the cooking chamber door 20, is directed to the franking 38 and from there can penetrate the fiber material of the core strand.

Fig. 8 shows a fir-like hook profile, which is integrally formed on the sealing body and with the door seal 30 in a corresponding gap or undercut of the cooking chamber flange can be inserted. This profile may extend continuously over the length of the door seal string or alternatively at certain locations, such as for the corners of the cooking chamber opening. In this illustration, for the sake of simplicity, no frankings are shown.

In Fig. 9 another alternative of the door seal without a core strand is shown, in which a hollow chamber 45 extends continuously in the axial direction of the door seal 30; the door sealing strip thus has the basic shape of a hose. Above and below radially arranged frankings 38 are provided. These clearances or openings can be punched after the extrusion of the strand and one opening is directed towards the cooking appliance interior, the other opening in the direction of the device exterior. Such openings are provided at regular intervals of, for example, 20 to 50 mm. Through the defined openings in the tube, the said passage results and so the condensate can drain. Possible contaminations that could lead to blockages of the openings are eliminated when the air escapes from the hollow chamber, as happens when the cooking chamber door is heated or closed. There are opposite openings without axial offset.

Fig. 10 shows a further variant of the door sealing strip in longitudinal section with sections of core strands 34 at regular intervals, which alternate with sections 45 without core strands. The clearances 38 of the passages are axially corresponding to the core strands and thus allow the already described above several penetrations of the seal. Often the

Door sealing strip attached only at the corners of the cooking chamber flange and held in the middle areas by bias. Since the elasticity of the core strands in the longitudinal direction is very low, the core-strand-free areas provide the desired elasticity. This embodiment is particularly advantageous when the door seal is made as a circumferentially closed ring.

Different embodiments of the invention can be freely combined. In particular, the different ways of attaching the door seal string are applicable to each of the illustrated types of the passage or passages. Parts with the same function are shown with the same reference numerals, even if they can be configured differently from embodiment to embodiment.

Reference numerals:

1.

Cooking appliance

5th

oven

8th.

Vapor / condensate

10th

Garraumflansch

20th

oven door

30th

Door sealing strip

32nd

seal body

34th

core strand

35th

First sealing surface

36th

Second sealing surface

37th

baffle

38th

Clearance / plastic-free area

39th

retaining profile

42nd

sealing lip

45th

hollow

50th

hook profile

60th

tub

Claims (13)

Door seal (30) of a cooking appliance (1) for sealing between a cooking chamber (10) and a cooking chamber door (20), wherein a first sealing surface (35) for sealing against the cooking chamber flange (10) and a second sealing surface (36 ) are provided for sealing against the cooking chamber door (20), characterized in that between the first sealing surface (35) and the second sealing surface (36) has a passage, in particular with clearances (38), provided a steam and / or Liquid passage in the transverse direction through the door seal (30) allows. Door seal (30) according to claim 1, characterized in that the door seal (30) has a core strand (34) made of a heat-resistant fiber material and that the passage of steam and / or liquid is realized by a penetration of the core strand. Door seal (30) according to one of the preceding claims, characterized in that the sealing body (32) comprises a sealing lip (42) with the first sealing surface (35) for sealing against the cooking chamber door (20) and further comprises a guide surface (37) for conducting the cooking chamber door (20) condensed and draining liquid to the passage. Door seal (30) according to the preceding claims, characterized in that a plurality of passages is provided. Door seal (30) according to one of claims 2 to 4, characterized in that the core strand (34) is designed as a fabric tube with a hollow chamber (45). Door seal (30) according to one of claims 2 to 4, characterized in that the core strand (34) is designed as a solid material. Door sealing strip (30) according to any one of claims 2-6, characterized in that the passage has two plastic-resistant portions (38) which extend continuously in the longitudinal direction of the door sealing strip and so the sealing body (32) of the first and second sealing surfaces (35, 36) divides into two separate, non-interconnected and adhering to the core strand segments. Door sealing strip (30) according to one of the claims 2-6, characterized in that the core strand (34) is coated in a net-like structure with the sealing body (32), so that a large number of not axially and radially surrounding the sealing body (32). 32) yield coated areas of the core strand. Door sealing strip (30) according to one of the preceding claims, characterized in that the door sealing strip (30) is designed as a closed ring for circumferential sealing of a cooking chamber opening of a cooking appliance (1). Door sealing strip (30) according to one of the preceding claims, characterized in that the door sealing strip (30) is manufactured as a continuous strand and preferably in an extrusion process. Door sealing strip (30) according to one of the preceding claims, characterized in that the door sealing strip comprises a hollow chamber (45) with radially arranged openings (38) of the hollow chamber (45), which in the installed Türdichtungsstrang (30) in the direction of the cooking chamber (5) and with radially arranged openings (38) of the hollow chamber, which in the installed door seal strand (30) point in the direction of the outside of the device. Cooking appliance (1) characterized in that a door sealing strip (30) according to one of the preceding claims at least partially on the lower sealing surface of the cooking chamber opening between the cooking chamber (10) and cooking chamber door (20) is arranged. Cooking appliance (1) according to claim 12, characterized in that a door sealing strip (30) according to one of claims 1 to 11 completely seals the cooking chamber flange.

Images