DE19931170A1 - Heat-insulating wall such as a refrigerator housing or a refrigerator door - Google Patents

Abstract

The invention relates to a heat-insulating wall, such as a refrigerator housing (10) or a refrigerator door (13), comprising an inner jacket layer (17) and an outer jacket layer (14), these two jacket layers (14, 15) being interconnected and surrounding an intermediate chamber (17) that can be evacuated. Heat-insulating material (18) is introduced into said intermediate chamber. Said heat insulating material (18) consists of vacuum insulated components (18) which are introduced into the evacuable intermediate chamber (17) in such a way that an evacuable residual volume (21) is formed.

Description

The invention relates to a heat-insulating wall such as a refrigerator housing or a refrigerator door, a dishwasher housing, a washing machine or a laundry schetrocker housing with an inner cladding layer and an outer cladding layer, wherein the two cladding layers are connected to one another and an evacuable intermediate Enclose space in which thermal insulation material is inserted.

With vacuum-insulated walls, such as those for refrigeration device housings or Refrigerator doors are proposed is the state of the art, their interior and their Form outer shell made of stainless steel to ensure a useful life in size External arrangement for 15 years, for housings based on vacuum insulation technology and reach doors. The stainless steel cladding layer is the one for required usability period to be considered leak or permeation rate enough, but the shape of the cladding layers and the functional and connection technology to be used, due to the principle, quite expensive to manufacture and therefore costly. With regard to the construction of the heat insulating walls e.g. B. to ensure that heat conduction via the inner, a room with reduced temperature level surrounding the outer layer, the room temperature maturity of the refrigerator or the refrigerator door exposed cladding layer at least white is avoided. For this purpose, membrane-like thin-walled connecting elements are found ment application, which are particularly sensitive to shock due to their thin walls and even with appropriate treatment a potential source of danger in the outward direction view of a leak in the evacuated wall and for this reason be covered with additional protective elements. Furthermore, it is necessary  the individual components of the heat-insulating walls, such as the inner and outer cladding layer and the connection serving to connect them element with a Ver ensuring the vacuum long-term stability of the connection binding technology, in the form of laser welding technology. That kind of verb Manure technology brings relatively high investment costs for the production of with heat-insulating walls. By using stainless steel for the Her position of the inner and outer cover layer is the weight of a refrigerator house or a power tool door, although thin-walled stainless steel for these cladding layers is used, also not insignificant.

The invention has for its object to propose measures based on which with a heat-insulating wall according to the preamble of claim 1 simple way the disadvantages of the prior art are avoided.

This object is achieved according to the invention in that the thermal insulation mat rial is formed from vacuum-insulated components, which with the formation of an evacu ible residual volume are introduced into the evacuable space.

The inventive construction of a heat-insulating wall for use dung z. B. in a refrigerator housing or a refrigerator door are so far to the Tightness of such walls over their useful life ge high demands significantly reduced. This is because the actual insulation capacity of the heat-insulating walls through the one low thermal conductivity, vacuum-insulated components provided which is at the same time arranged within a pressure-reduced space are, whereby the pressure difference with respect to the vacuum-insulated components is reduced is. By reducing the pressure difference, the gas entry is dependent on this the vacuum-insulated components significantly reduced, so that the combined Structure and the resulting interaction of the evacuated insulation Components, namely the vacuum-insulated components on the one hand and the evacuated Residual volume between the outer and the inner cladding layer, on the other hand, a fro position of heat-insulating walls is possible, their heat insulation capacity at least essentially that with thermal insulation based on stainless steel cladding layers corresponding walls. In contrast to stainless steel cladding The manufacture of the walls according to the invention is much easier and walls with reduced manufacturing costs. In addition, for the manufacture of in  neren and the outer cladding materials to which ge to make stricter requirements for gas and water vapor permeability and which are used to connect the cladding layers in the course of producing the war insulating walls using cost-effective connection techniques to let.

Adequate positional stability of the inner and outer covering layer reached when according to a preferred embodiment of the counter state of the invention is provided that the vacuum insulated components as a support serve to support the inner cladding layer and the outer cladding layer.

The heat-insulating tubs are particularly flat and can be manufactured without sink marks applications for cooling unit housings, cooling unit doors, dishwasher housings se, washing machine and dryer housing, if after a next one drafted embodiment of the invention provides that the vacuum-insulated construction elements have a material thickness which is at least approximately the clear width between the inner cladding layer and the outer cladding layer.

According to a next preferred embodiment of the subject of the invention it is provided that the vacuum-insulated components are plate-like and / or as molded parts are trained.

Through the use of such components, a particularly homogeneous backfill is possible of the space between the inner and outer cladding layer possible, wherein in particular through the use of those adapted to the contour of the intermediate space Moldings a particularly favorable filling of the space under simultaneous Preservation of the buffer volume serving as the remaining volume has been reached. In particular through a provision of molded parts with a clearance between the inner and material thickness corresponding to the outer cladding layer results in a high level flatness of the heat-insulating walls after the evacuation of the intermediate space. The moldings can z. B. as a corner element or as in a refrigerator Housing U-shaped component used to form the housing walls Find application.

Particularly favorable, long-term stable values for the thermal insulation result himself, if after a further advantageous embodiment of the subject matter of the invention  is provided that the vacuum insulated components as in an aluminum ver Sheets of open-cell polystyrene foam or open-cell foam inserted in bund-film Polyurethane foam are formed or pressed into sheet form and opposed by one Gas permeability acting plastic film surrounding silica are formed.

According to a further preferred embodiment of the subject of the Er Invention is provided that the inner cladding layer and / or the outer cladding layer non-cutting deformable, thermoplastic and / or non-cutting deformable pla tin-like, metallic material are formed.

Leave through the use of non-cutting deformable, thermoplastic example in a particularly simple and inexpensive way during the molding process as a plastic present in board form in refrigerators and freezers functional parts, such as support measures for evaporator shelves, cooling Store well, condensate drainage channels or the like directly on. By the use of plastic materials to create the inner and outer Envelope is the problem of a given by the connection of the two layers If necessary, the thermal bridge is clearly mitigated, which means the energy consumption use of a refrigerator is not insignificantly reduced. Furthermore, the inventor construction according to the heat-insulating wall also a combination of possible from metallic material and a covering layer made of plastic, where in particular through the use of metallic material for production the inner cladding layer facing the cold room of a refrigerator, a special one can achieve hygienic cleaning for this.

According to a preferred embodiment of the subject matter of the invention, it is provided hen that the inner cladding layer and / or the outer cladding layer with reinforcing element elements and / or stiffening elements is provided, which form the evacuator serve residual volume.

By attaching reinforcement and / or stiffening elements to the view surfaces of the inner and / or the outer cladding layer are also small Wall thicknesses sufficiently stable, so that even after the evacuation of the rest one by supporting the reinforcing and / or stiffening elements on the vacuum-insulated components there is already sufficient flatness for the is reached in both layers. At the same time by the after the evacuation of the  Remaining volume acting on the vacuum-insulated components and / or stiffening elements fixing the vacuum-insulated components internally half of the space.

The stiffening and / or reinforcing elements can be produced particularly cost-effectively elements, if after a next advantageous embodiment of the subject Invention is provided that the inner wall and / or the outer wall at least at least partially, as a reinforcing and / or stiffening design to form the evacuable residual volume. Especially in deep drawing drive non-cutting deformed plastic boards for the production of the inner and / or outer cladding can be inexpensively targeted shapes in the visible Chen bring these cladding walls, the shapes at the same time as a function elements, for example, for holding evaporator shelves or for support of refrigerated goods shelves or the like can be formed.

According to an alternative embodiment of the object of the invention is provided see that the evacuable residual volume by an outside of the evacuable Zwi arranged additional volume is formed, which is fluidically the space is coupled.

This results in the possibility of the two cladding walls without stiffening and / or Reinforcement measures to support them directly on the vacuum-insulated components elements to bring the system, whereby the flatness of the envelope walls directly from the Flatness of the vacuum insulated components depends, so that the flatness of the cladding walls can be mastered with high precision.

Particularly favorable in terms of maintaining the evacuated residual volume an inner and / or outer shell layer has emerged if after a wide one ren, preferred embodiment of the object of the invention is provided that the inner cladding layer and / or outer cladding layer is provided with means which the At least reduce water vapor and oxygen permeability as much as possible.

As particularly effective in terms of reduction and / or even avoidance the water vapor permeability on the outer covering layer and / or the inner covering Layer based on polyolyfins or polyvinylidene chloride or Perfluoroalkoxy polymers highlighted.  

Particularly effective in reducing or even avoiding gas permeability to the outer covering layer and / or inner covering layer have become apparent Ethylene-vinyl alcohol copolymer or by polyacrylonitrile or by polyamide made funds exposed.

In a particularly simple and effective way, both the gas permeability is also the water vapor permeability in the case of an outer envelope made of plastic layer and / or avoided with an inner envelope wall formed of plastic, if according to a last preferred embodiment of the subject of the invention is seen that the means by sputtering on the outer cladding layer and / or the inner cladding layer produced metal layer are formed.

In this context, a metal layer made of aluminum in particular has proven favorable.

The layer to reduce water vapor and gas permeability is both in In the case of the metal layer produced by sputtering as well as in the case of the specially for Avoidance of water vapor permeability, gas permeability oriented Layers each applied to the surfaces of the envelope walls, which the space are facing, both the single layer to reduce or avoid the Water vapor permeability as well as the single layer for reduction or avoidance gas permeability by lamination or co-extrusion to the inner and / or the outer covering layer is applied.

The invention is in the following description using the example of two in the beige added drawing simplified refrigerator housings explained.

Show it:

Fig. 1 in a simplified schematic representation of a first Ausfüh approximate shape of a refrigerator housing with a closed door with bounded by cladding, equipped with vacuum-insulated elements, evacuated space in sectional representation from the side and

Fig. 2 shows a simplified schematic representation of a second embodiment of a refrigerator housing with the door closed with an evacuated space bordering, on vacuum-sealed components adjacent wall walls, in sectional representation from the side.

Referring to FIG. 1 a purely schematic for use in a domestic, refrigerator or freezer suitable, heat-insulating casing 10 is simplified shown, the thermal insulation is based on vacuum insulation technique. The heat-insulating housing 10 has a usable space 11 designed as a cold space and is equipped for closing bees usable space 11 with a door 13 resiliently resting on its opening edge via a magnetic seal 12 . The door 13 and the housing 10 are vacuum-insulated based on the same technology and have a wall structure which serves to achieve their heat-insulating effect. In the present exemplary embodiment, the wall structure of the door 13 has a one-piece outer cladding 14 , which is made from thermoplastic material without cutting, for example in the deep-drawing process, which is used for fastening it to the door 13 for fastening a door handle (not shown) and which is used on the housing 10 to form its outer casing or outer cladding layer is seen. Spaced from the outer cladding 14 , the wall structure used for the door 13 and the housing 10 in the present case also has a one-piece inner cladding 15 , for example in the deep-drawing process made of thermoplastic plastic, which in the present case already introduced stiffening elements 16 during its manufacturing process in the form of stiffening ribs or stiffening beads, which face the outer cladding with their free end. Both the outer lining 14 and the inner lining 15 are made, for example, of impact-resistant polystyrene with a material thickness of 0.8 to 2.0 mm and have a layer-like structure which, in addition to the thermoplastic plastic, has a layer for reducing or even inhibiting the gas permeability and a layer for reducing or even inhibiting the Wasserdampfdurchläs liquid, the counteracting the water vapor permeability layer z. B. is applied by coextrusion or lamination and on the basis of polyolefins such as high density polyethylene, or polypropylene or other materials such. B. polyvinylidene chloride or perfluoroalkoxy polymers is formed. The layer downstream of this layer, which counteracts the gas permeability, is likewise applied to the thermoplastic material by coextrusion or lamination and consists, for example, of ethylene-phenyl alcohol copolymer or polyacrylonitrile or polyamide. In combination with the outer clothing 14 made of polystyrene or the inner lining 15 , there is a layer of ethylene-phenyl alcohol copolymer with a layer thickness of approximately 470 μm and a layer of perfluoroalkoxy polymer serving as a water vapor barrier, which counteracts or prevents gas permeability a layer thickness of 30-35 microns be proven. The outer lining 14 provided with the layers or inner lining 15 are connected to one another at their free end in a vacuum-tight manner by welding, gluing or the like and, in the present case, together enclose an intermediate space 17 which can be evacuated. In this vacuum-insulated components 18 are introduced, which are formed in the present embodiment as vacuum insulation panels. The plate-shaped, vacuum-insulated components 18 have a support body 19 formed, for example, from open-cell polystyrene foam, or open-cell polyurethane foam or from silica, which is arranged within a vacuum-tight envelope 20 , which in the evacuated state on the upper surface of the support body 19 is present and which is formed in the case of an open-cell polyurethane foam or an open-cell polystyrene foam from an aluminum composite film of the trade name "Toyo" and in addition to a layer of polyethylene, aluminum, a metallized layer of polyethylene terephthalate has a layer of polyamide, which creates both a water vapor and a gas barrier. In the event that 19 silica is used for the support body, for their vacuum-tight envelope, for example formed from a plastic film, mainly to a barrier against gas permeability to eight, since the silica itself acts as a cooler for water vapor. The vacuum-insulated components 18 introduced into the intermediate space 17 lie with their sheathing 20 on the free ends of the stiffening elements 16 projecting into the intermediate space 17 , whereby an evacuable residual volume 21 is formed within the intermediate space 17 , through which a significantly reduced volume after its evacuation process Pressure difference between the vacuum-insulated components 18 and the space 17 is generated, whereby the gas passage to the vacuum-insulated components 18 , which depends on this pressure difference and contributes to reducing the heat insulation capacity, is significantly reduced.

Fig. 2 shows a simplified schematic representation of a second embodiment of a thermally insulating housing 30 formed on a vacuum insulation basis, which accommodates at least one cold space 31 , which is accessible via a magnetic seal 32 resiliently resting on the opening edge of the housing door 33 by means of a magnetic seal 32 . Both the door 33 and the housing 30 are based on identical Wärmiso lationstechnik and also have an identical wall structure, so that in the following description for the wall structure of the door 33 and that of the components used for the housing 30 with identical reference numerals are. To achieve the heat insulation for the door 33 and the housing 30 both have a thermoplastic plastic, for example, by thermoforming, molded one-piece outer panel 34 , which serves in the case of the door 33 for fastening a door handle, not shown, while the outer panel 34 for their use on the housing 30 forms the outer jacket or outer cladding layer. In contrast to the door 33 , the outer panel is equipped in the case of its use as an outer jacket for the housing 30 with, for example, directly on the outer panel with molded, serving as a residual volume 35 additional volume.

At a distance from the outer panel 34 , both the door 33 and the housing 30 also have a non-cutting material made of thermoplastic, e.g. B. in the deep-drawing process, molded, one-piece inner lining 36 or inner cladding, which is provided in the case of Ge housing 30 for lining the cold room 31 and which for their use at the door 33 facing the cold room 31 .

On the inner panel 36 of the door 33 , in contrast to the inner panel 36 used for the housing 30 , an additional volume serving as a residual volume 37 is also formed, which projects into the cold space 31 in the present exemplary embodiment. Both the inner panel 36 and the outer panel 34 is in both use cases, namely for the door 33 and the housing 30 in terms of their wall construction identical to that for the door 13 and the housing 10 for use coming inner panel 15 or outer panel 14 . The outer cladding 34 and the inner cladding 36 are connected at their free ends such as the outer cladding 14 and the inner cladding 15 in a vacuum-tight manner by connection techniques such as welding, gluing or the like and enclose an evacuable space 38 in which vacuum-insulated components 39 , for example in Form of so-called vacuum insulation panels are introduced, which, like the vacuum-insulated components 18, have a plate-like support body 40 and a cover 41 surrounding the support body 40 in a vacuum-tight manner, 41 materials being used for the support body 40 and its cover, which are identical to the support body 19 used for the components 18 and de ren envelope 20 are formed. The vacuum-insulated components 39 are matched in their vorlie exemplary embodiment in terms of their strength to the clear width of the intermediate space 38 , so that the vacuum-insulated components 39 after the evacuation process of the vacuum-tight, enclosed by the inner lining 36 and the outer lining 34 intermediate space 38 to support the inner lining 36 and the outer cover 34 serve, whereby at least largely flat visible surfaces are generated for both the door 33 and the housing 30 . After the evacuation of the intermediate space 38 , both in the case of the housing 30 afs and in the case of the door 33 through the additional volumetric coupling 35 to the fluid mechanically coupled to the intermediate space 38 or 37, as in the case of the housing 10 or the door 13, there is a reduction in the pressure difference between the vacuum-insulated components 39 and the intermediate space 38 are generated, whereby the heat insulation effect of the door 33 and the housing 30 gas passage to the vacuum-insulating components 39 is considerably reduced. Here, the additional volumes 35 and 37 serve as a buffer for maintaining a reduced pressure difference between the intermediate space 38 and the vacuum-insulating components 39 for long-term stable maintenance of the thermal insulation capacity of the door 33 and the housing 30 .

Contrary to the two exemplary embodiments described, by preventing the water vapor and gas permeability, an aluminum layer produced by sputtering can be used both for the outer cladding 14 and 34 and for the inner cladding 15 and 36, respectively. Furthermore, it is also possible to either manufacture the outer linings 14 or 34 and the inner linings 15 or 36 from stainless steel, or else to provide a combination of the two materials for the production of the housing and the door, it being expedient for hygienic reasons is to design the inner cladding from stainless steel.

Claims (13)

1. Heat-insulating housing such as a refrigerator housing or a refrigerator door, a dishwasher housing, a washing machine or laundry dryer housing or the like with an inner cladding layer and an outer cladding layer, the two cladding layers being connected to one another and an evacuated space enclose in which heat insulation material is introduced, characterized in that the heat insulation material is formed from vacuum-insulated components ( 18 , 39 ) which, with formation of an evacuable residual volume ( 21 , 35 ) in the evacuable space ( 17 , 38 ) are. 2. Heat-insulating wall according to claim 1, characterized in that the vacuum-insulated components ( 18 , 39 ) serve as a support body for supporting the inner cladding layer ( 15 , 36 ) and the outer cladding layer ( 14 , 34 ). 3. Heat-insulating wall according to one of claims 1 or 2, characterized in that the vacuum-insulated components ( 39 ) have a material thickness which corresponds at least approximately to the clear width between the inner cladding layer ( 36 ) and the outer cladding layer ( 34 ). 4. Heat-insulating wall according to one of claims 1 to 3, characterized in that the vacuum-insulated components ( 18 , 39 ) are plate-like and / or are formed as molded parts. 5. Heat-insulating wall according to one of claims 1 to 4, characterized in that the vacuum-insulated components ( 18 , 39 ) are formed as a vacuum-tight in an aluminum composite sheet made of open-cell polystyrene foam or open-cell polyurethane foam or as vacuum-tight in a plastic sheet introduced as a gas barrier is formed. 6. Heat-insulating wall according to one of claims 1 to 5, characterized in that the inner cladding layer ( 15 , 36 ) and / or the outer cladding layer ( 14 , 34 ) made of non-cutting deformable, thermoplastic and / or non-cutting deformable, board-like , metallic materials are formed. 7. Heat-insulating wall according to one of claims 1-6, characterized in that the inner cladding layer ( 15 ) and / or the outer cladding layer ( 14 ) is provided with reinforcing and / or stiffening elements, which form the remaining volume ( 21 ) serve. 8. Heat-insulating wall according to one of claims 1 to 7, characterized in that the inner cladding layer ( 15 ) and / or the outer cladding layer ( 14 ) at least partially, as stiffening and / or reinforcing elements ( 16 ) serving shapes for formation of the evacuable residual volume ( 21 ). 9. Heat-insulating wall according to one of claims 1 to 8, characterized in that the evacuable residual volume ( 37 ) is formed by an additional volume outside the evacuable space ( 38 ) arranged, which is fluidically coupled to the space ( 38 ). 10. Heat-insulating wall according to one of claims 1 to 9, characterized in that the inner cladding layer ( 15 , 36 ) and / or the outer cladding layer ( 14 , 34 ) is provided with means which at least the water vapor and oxygen permeability reduce as much as possible. 11. Heat-insulating wall according to claim 10, characterized in that the means for at least largely reducing the water vapor permeability speed on the outer cladding layer ( 14 , 34 ) and / or the inner cladding layer ( 15 , 36 ) by polyolyfins or by polyvenylidene chloride or by perfluoroacoxypolyme re are formed. 12. Heat-insulating wall according to claim 9, characterized in that the means for at least largely reducing the oxygen permeability of the outer covering layer ( 14 , 34 ) and / or the inner covering layer ( 15 , 36 ) by ethylene-vinyl alcohol copolymer or by polyacrylonitrile or polyamide are formed. 13. Heat-insulating wall according to claim 9, characterized in that the means are formed by an aluminum layer produced by sputtering on the outer cladding layer ( 14 , 34 ) and / or the inner cladding layer ( 15 , 36 ).