US20100095622A1

US20100095622A1 - Vacuum insulation panel and method for the production thereof

Info

Publication number: US20100095622A1
Application number: US12/522,924
Authority: US
Inventors: Gerd Niemoller
Original assignee: Wall AG
Current assignee: Wall AG
Priority date: 2007-01-13
Filing date: 2008-03-13
Publication date: 2010-04-22
Also published as: WO2008141689A1; ZA200904777B; EP2126233A1; DE102007035851A1; CA2674479A1; RU2009130807A

Abstract

The present invention relates to a vacuum insulation panel (1) having a core (5) having insulating hollow spaces and cover layers (11) closing off the core (5) from the environment, the hollow spaces of the core (5) being formed by two chambers (3) sealed off from each other in a gas-tight fashion, extending together with the walls (4) or intermediate walls thereof from one cover layer (11) to the other cover layer (11) and being formed from the walls (4) or intermediate walls and the cover layers (11). The present invention further relates to a method for producing such a vacuum insulation panel (1), wherein a) plates (7) are produced having the shape and arrangement in cross section of walls (4) of the half chamber (3) connecting to each other, but being substantially longer than the height of the walls (4) of the chambers (3), then b) a composite (9) then being produced, in that a further such plate (7) is laid on a first such plate (7) such that the entire chambers (3) are formed, c) the plates (7) are then connected to each other, in a gas-tight and permanent fashion, at the contact points (8) thereof, d) further plates (7) are then laid on the uppermost plate (7) of the composite (9) according to step b) and connected, in a gas-tight and permanent fashion, to the uppermost plate (7) of the composite (9) according to step c), e) the composite (9) is further cut transverse to the plates (7) into chamber discs (17) having the desired thickness corresponding to the intended chamber height, and f) the chamber discs (17) are connected, in a gas-tight and permanent fashion, to the cover layers (11) on the open sides of the chambers (3).

Description

The present invention relates to a vacuum insulation panel according to the preamble of Claim 1 and also to a production method for this panel.
Such vacuum insulation panels are known from practice. They have very high thermal and acoustic insulation properties and are therefore used, e.g., as insulation panels. The vacuum insulation panels named above are made from a core made from an open porous material, for example, a noncompressive foam and sealing cover layers or outer skins.
The vacuum insulation panels named above have the disadvantage, among others, that the vacuum is lost with only slight damage to the outer skin. For example, if a hole penetrating the cover layers is drilled into the panel, then the core draws in air and the insulation effect is lost or significantly reduced. Another disadvantage is that the vacuum insulation panels named above cannot be subjected to finishing work, but instead must already have, from the start of the production in the factory, before the evacuation of the core, the shape in which they are then installed or used in some other way. Later finishing work is not possible without the loss or drastic reduction of the insulation property. Furthermore, the mechanical load capacity of known vacuum insulation panels is insufficient for many applications. These vacuum insulation panels cannot be used as load-bearing elements, but instead are used merely for insulation.
The present invention has the goal of creating a vacuum insulation panel that can be subjected to finishing work and realizes this goal with a vacuum insulation panel according to Claim 1 and also a production method for a vacuum insulation panel according to Claim 18.
Thus, according to the invention, a vacuum insulation panel is created with a core with hollow spaces and also cover layers closing the core in a tight fashion from the surroundings, wherein the hollow spaces of the core are formed by chambers that are closed in a tight fashion relative to each other and that reach, together with their intermediate walls, from one cover layer to the other cover layer.
Such a vacuum insulation panel according to the invention has numerous advantages. It can be used both as a high insulation panel that can be cut arbitrarily, even after the evacuation, and that essentially maintains its function, even with a partially damaged surface, and also as a static structural element from which load-bearing walls could be built.
Advantageously, the walls or intermediate walls of the chambers form a honeycomb structure. Here, it could be further provided advantageously that the honeycomb structure is rectangular, hexagonal, or octagonal, contains circular shapes, or is regular or irregular.
Another preferred configuration is that each cover layer is made from a gas-tight material or is coated with a gas-tight material. Alternatively or additionally, it could be provided that each cover layer contains a layer or plate made from, in particular, reinforced epoxy, melamine, or phenolic resin or the like in direct contact with the walls or intermediate walls of the chambers, wherein, in a further preferable way, the reinforcement of the cover layer contains fiberglass material, kraft paper, sisal or the like.
Another advantageous configuration is that each cover layer has, on its side facing away from the walls or intermediate walls of the chambers, a protective layer, wherein, in particular, the protective layer can contain a reflective high barrier film or an aluminum foil or a high barrier coating or aluminum coating or the like.
Advantageously, each cover layer has a thickness of greater than approximately 0.5 mm, advantageously greater than ca. 1 mm, and especially preferred approximately 1 mm.
Another preferred configuration is that the walls or intermediate walls of the chambers are made from a gas-tight material or are coated with a gas-tight material.
Furthermore, it could advantageously be provided that the walls or intermediate walls of the chambers contain paper or cellulose and/or that the walls or intermediate walls of the chambers have a coating with melamine resin, phenolic resin, or a melamine resin-phenolic resin derivative and/or that the walls or intermediate walls of the chambers contain kraft paper or hard paper, in particular, with reinforcement. Alternatively or additionally, it is preferred that the walls or intermediate walls of the chambers contain a metallic foil or are coated with a metallic layer.
Another advantageous configuration consists of walls or intermediate walls of the chambers exhibiting, with respect to one cubic meter, heat conductivity of less than ca. 0.3 W/mK, advantageously less than approximately 0.2 W/mK, and especially preferred less than approximately 0.1 W/mK. Corresponding values are also influenced by the selection of the material pairing.
Furthermore, the walls or intermediate walls of the chambers could advantageously have a thickness of approximately 0.5 mm.
In the chambers, advantageously a vacuum of approximately 98% prevails, or a heat-insulating gas, such as argon or another noble gas or a corresponding gas mixture, is contained in the chambers.
In another advantageous configuration, it is provided that the core is sealed with artificial resin or the like at its free edges between the cover layers.
In one special configuration, the invention further relates to a vacuum insulation panel with an evacuated core or a core filled with an insulating gas, and the core has, on both sides, cover layers made from a gas-tight material or coated with a gas-tight material. Here, the core is made from a plurality of individual vacuum chambers that are formed by walls or intermediate walls, wherein these walls extend, for example, perpendicular to the cover layers and are arranged, in particular, in a regular pattern and are connected to the cover layers in a gas-tight fashion and are made from a gas-tight material or are coated with a gas-tight material. Here, the walls could form a honeycomb pattern or else, in cross section, circular tubules, or could have other geometries. The walls or intermediate walls of the vacuum chambers or, in general, chambers, could be made, in particular, from cellulose coated with a phenolic resin, wherein, alternatively, the construction from a metallic foil or from a material coated with a metal or another similarly acting material comes into consideration. The walls or intermediate walls thus form a plurality of individual vacuum chambers that are covered on both sides with a cover layer and are thus closed. At least one of the cover layers is formed, for example, under vacuum conditions, so that the chambers are evacuated.
The vacuum insulation panel according to the invention could be produced in a large surface-area or endless configuration and then could be cut to the required size: through cutting, only the insulation effect of the actually cut chambers is lost—which is different than vacuum insulation panels known from practice—because these chambers are each closed in a gas-tight fashion relative to the adjacent chambers. For example, even if a nail is driven into one of the cover layers, the insulation effect of only the affected chamber is lost, but not that of the vacuum insulation panel as a whole.
The walls, advantageously in a regular configuration, and the sandwich construction made from the honeycomb structure between the two cover layers impart high strength to the vacuum insulation panel, especially also relative to forces introduced to the vacuum insulation panel in the plane of the cover layers. The vacuum insulation panel thus could be used as a structural element of a structure and for other purposes. In principle, the chambers could also be filled, for example, with an open-pore foam, as is known from the state of the art, as a planar, continuous core material, or also with a closed-pore foam.
The honeycomb body can absorb high mechanical loads, much higher than can wood plates, in connection with the cover layers and, indeed, the honeycomb core weighs, e.g., only 33-60 kg/m³, in particular, for example, only ca. 44 kg/m³.
It is noted again that, instead of the vacuum in the chambers, heat-insulating gases could also be used. In particular, the possibility is imagined to use, e.g., argon or other noble gases for special applications.
A vacuum insulation panel according to the invention could be used for the following uses (wherein these uses for the construction of the vacuum insulation panel are also disclosed simultaneously as inventive concepts belonging to the invention):
Gates (any type, e.g., garage doors, industrial doors, etc.),
Doors of any type,
Swimming pool insulation,
Coolers, refrigerators, freezers, refrigerated rooms, refrigerated warehouses or cold storage buildings.
Hot-storage containers for keeping food warm (e.g., rolling containers in airplanes, etc.),
Pipe insulation of any type,
Ship insulation, room container construction for ships, etc.,
Container construction, in general, e.g., refrigerated containers, sanitary containers, office containers, magazine containers, mobile homes, etc.,
Floor coverings of any type, e.g., laminate flooring, refrigerated warehouse floors with aluminum, ribbed visual appearance, etc.,
Intermediate coverings, house coverings of any type,
House roof, warehouse roof (flat roof, etc.) with various associated visual appearances,
Walls as structural elements (replacement for stone) and as additional insulation worked into the stone (brick, concrete block, sandstone, etc.),
Door, gate, and window frame insulation of any type,
Roller blind blocks of any type could be produced or at least insulated with vacuum insulation panels,
Heating systems (the system could be insulated),
Mobile home construction,
Swimming building construction,
Prefabricated building construction of any type,
Truck trailer construction (refrigerated trailer construction, etc.),
Prefabricated garage construction (e.g., automobile automatically heats up the garage with the remaining exhaust heat),
Passive warehouse and passive house construction of any type,
Furniture industry, etc.,
Particle board replacement,
Sheetrock replacement,
In a transparent visual appearance, as a window pane replacement or as a multi-wall replacement
Paving stone (ground covering of any type; does not transmit the coldness of the ground)
High-rise rooms, high-rise containers, high-rise structural elements, etc.,
Vehicle insulation for, e.g., battery insulation, etc.,
Solar collector plates that produce distilled water
for hot-water accumulators, etc.
Cover and wall insulation with the associated visual appearance both in areas inside and also outside,
Frost-proof street layer (below the blacktop; no more risk of sliding)
Radiation protection (e.g., from radio waves in house construction)
in any areas where space savings or stability is demanded
Other applications or uses of vacuum insulation panels according to the invention lie in the field of sound suppression and sound insulation.
In addition, the invention creates a production method for such vacuum insulation panels. This method according to the invention for the production of a vacuum insulation panel contains the following steps:
a) plates are produced that have, in cross section, the shape and arrangement of walls of half-chambers connected one next to the other but are significantly longer than the height of the walls of the chambers,
b) then a composite is produced in which, on a first such plate, another such plate is placed so that whole chambers are formed,
c) then the plates are connected to each other in a permanent and gas-tight fashion at their contact points,
d) then additional plates are placed according to step b) one after the other onto the uppermost plate of the composite and are connected in a permanent and gas-tight fashion to the uppermost plate of the composite according to step c),
e) then the composite is cut perpendicular to the plates into chamber discs with the desired thickness corresponding to the intended chamber height, and
f) finally, the chamber discs are connected on the open side of the chambers in a permanent and gas-tight fashion to the cover layers.
Advantageously, in the method it is further provided that the cover layers are connected one after the other to the corresponding honeycomb disk, and that the second cover layer is connected to the assembly made from the chamber disk and the first cover layer at a low pressure, in a vacuum, or in a gas atmosphere with a gas that is provided as a filling for the chambers. Alternatively, it could also be provided that the cover layers are simultaneously connected to the corresponding honeycomb structure and that the cover layers are connected to the chamber disk at a low pressure, in a vacuum, or in a gas atmosphere with a gas that is provided as a filling for the chambers.
In particular, the production of the honeycomb or, more precisely, its walls, from paper coated with melamine resin subject to pressure (30 bar) and heat (185° C.) is advantageous and preferred. This type of honeycomb production has many advantages:
thin honeycomb walls measuring approximately 0.5 mm are produced that can carry high loads;
high thermal load capacity;
low weight; economical production; ultra-fast wetting (for example, in 6 s);
simple production;
favorable tool prices, and many others.
In addition, the process of honeycomb evacuation according to the invention is very advantageous.
Below, a processing section is shown in a special, preferred configuration:
1. Preimpregnated paper is produced
2. The paper is preheated in a heating station, so that it becomes soft and can be deformed
3. In a preform, a ram brings the paper into a mold so that, in a side press, 30 honeycombs, or another desired or suitable number, could be pressed at one time; preferably, each ram moves one after the other into the paper, so that it could be redrawn from one side
4. In the side press, for 30 honeycombs, or another desired or suitable number, the oblique parts are pressed simultaneously, the base remains unlinked
5. The honeycombs are fused in that half honeycombs are placed one on top of the other with their not-yet-linked bases and pressed together with a press, so that the honeycomb bases fuse together and a complete honeycomb is produced; this can be performed in a so-called honeycomb fusing device in which the honeycomb bases are fused to each other.
The honeycomb block is produced from one side in that a half honeycomb is fused onto the previous half honeycomb. This is realized in that an anvil is lowered into the last honeycomb and a fusing ram presses against the anvil from one side. In this way, the two not-yet-linked honeycomb bases are fused to each other. If the anvil is made from a rather delicate ram, it is moved downward into a stabilization plate, so that the anvil is held on two sides. In this way, e.g., 30 honeycomb bases are fused to each other simultaneously.
From the present document, additional preferred and advantageous configurations of the production method for vacuum insulation panels according to the invention are produced. This produces, in particular, additional configurations of this method that are worthy of protection.
Additional preferred and/or advantageous configurations of the invention and their individual aspects will become apparent from the claims and their combinations, as well as from the present application document.

The invention will be explained in greater detail below using embodiments with reference to the drawing merely as an example, in which

FIG. 1 shows, in a schematic perspective view, an embodiment of a preproduction stage of a vacuum insulation panel,

FIG. 2 shows, in a schematic side or longitudinal section view, in cutaway, a vacuum insulation panel according to the embodiment of the preproduction stage in FIG. 1,

FIG. 3 shows, in a schematic view, a part of the production process of the vacuum insulation panel from FIG. 2,

FIG. 4 shows, in a schematic view, a part of the production process that is larger than the diagram of FIG. 3 for the vacuum insulation panel from FIG. 2,

FIG. 5 shows, in a schematic top view, a part of a vacuum insulation panel from FIG. 2 in a preproduction stage,

FIG. 6 shows, in a schematic perspective view, an embodiment of another preproduction stage of a vacuum insulation panel,

FIG. 7 shows, in a schematic view, the penultimate process of the production process for the vacuum insulation panel from FIG. 2,

FIG. 8 shows, in a schematic view, the last process of the production process for the vacuum insulation panel from FIG. 2,

FIG. 9 shows, in a schematic section view, an alternative construction of the layout of the core, and

FIG. 10 shows, in a schematic perspective view, the alternative construction of the layout of the core according to FIG. 9.

With reference to the embodiments and applications described below and shown in the drawings, the invention will be explained in more detail using examples, i.e., it is not limited to these embodiments or applications or to the combinations of features within these embodiments and applications. Features of the method and device are also given analogously from descriptions of the device or method.
Individual features that are specified and/or shown in connection with an actual embodiment are not limited to this embodiment or the combination with the other features of this embodiment, but instead could be combined in the scope of technical possibility with any other variants, even if these are not specifically discussed in the present document.
The same reference symbols in the individual figures and diagrams designate components that are identical or similar or that act identically or similarly. With reference to the diagrams, those features that are not provided with reference symbols are also clear, independent of whether those features are described below or not. On the other hand, features that are included in the present description but are not visible or not shown in the drawing are also easily understandable to someone skilled in the art.
In FIG. 1, a preproduction stage 2 is shown schematically from an embodiment of a vacuum insulation panel 1 in a perspective view for illustrating the shape and arrangement of chambers 3 and also their walls 4 or intermediate walls. FIG. 2 shows schematically, in a side view or a longitudinal section, the layout of the vacuum insulation panel 1. The vacuum insulation panel 1 will be explained in greater detail below in connection with FIGS. 3-8, and in the course of an embodiment of a production method together with the corresponding production steps.
The vacuum insulation panels 1 are made from a chamber core 5, the honeycomb that was understood for the present embodiment and therefore could also be designated as a honeycomb core. A hexagonal shape is used, wherein octagonal and other shapes, including irregular shapes, are also possible. The chamber core 5 is formed by the walls 4 and thus contains the chambers 3. Such constructions and structures are very stable, require little material, and are also very light.
For forming the chambers 3 in the form of half-chambers 6, corresponding plates 7 are pressed and then adhered to each other to form the whole chambers 3, as FIGS. 3-6 show, or alternatively fused. In this way, closed individual systems are produced. The produced plates could also be designated as half-chamber plates 7 and are placed one on top of the other in the arrangement shown in FIG. 1 and adhered, for example, to form a rigid and gas-tight connection at their contact points 8, wherein a new plate 7 is preferably always placed on an existing composite 9 and then adhered, before the next plate 7 is placed and adhered, etc. Such a block or composite 9 is cut perpendicular to the chamber or honeycomb openings 10, so that the height of the chambers 3 and their walls 4 produces the height of the chamber or honeycomb core 5, as is shown in FIG. 6. In FIG. 6, dimensions are specified that are to be understood, furthermore, only as examples.
The chamber openings 10 are closed on both sides with a cover layer 11 by mounting the cover layers 11 in a sealed and rigid fashion on the corresponding sides of the chamber core 5. In this way, many small closed cells or chambers 3 are produced, and the height of the chambers 3 together with the thickness of the cover layers 11 produces the thickness of the vacuum insulation panel 1. Advantageously, the two cover layers 11 are adhered to the chamber core 5 one after the other in separate processing steps, and the second cover layer 11 is adhered, in particular, in a ca. 98% vacuum. Instead of adhesion, other attachment types are possible, such as fusing or direct connection to each other by means of materials that are not yet cured or only partially cured in the chamber core 5 and/or the cover layers 11. Preferably, the material of the cover layers 11 contains a not-yet-cured resin, so that the curing of the resin takes place in a vacuum, in each case during the application and connection of the second cover layer 11, so that this vacuum is automatically produced and maintained in the individual chambers or honeycomb cells 4.
Preferably, the cover layers 11 are made from a reinforced epoxy resin. As the flow chart-like diagrams of FIGS. 7 and 8 show, each cover layer 11 is introduced wet in a single production step into a mold and cures in a vacuum. In this way, the walls 4 of the chambers 3 are pressed into the not-yet-linked cover layers 11, so that during the curing of the resin of each cover layer 11, the walls 4 of the chambers 3 are connected in an air-tight fashion to this cover layer 11. Through this procedure, the advantage is achieved that for the quasi-combined production and attachment of the cover layers 11 on the core 5, the cover layers 11 are connected in a rigid, nondetachable, and also gas-tight fashion to the wall material of the core 5.
In this way, a sandwich material is produced with high stiffness, low weight, and very little framework. The core 5 with the walls 4 of the chambers 3, that is, without cover layers 11, has, for special embodiments, a volume weight of ca. 60 kg/m³and a framework ratio to one cubic meter of 1:17. This ratio, however, could also lie in the range of 1:33. Such a low framework/volume ratio benefits the insulating power.
For the cover layers 11, other materials could also be used, such as a derivative made from melamine and phenolic resin, which represents a very economical solution. Under certain circumstances, such cover layers 11 are connected separately to the core 5 of the vacuum insulation panel 1, for example, by means of adhesion. Other plastics could also be used. In particular, the cover layers 11 could also contain reinforcement 12 made from glass matt, kraft paper, sisal or similar materials. An especially preferred layer thickness of the cover layers 11 lies at approximately 1 mm.
In another configuration, the cover layers 11 are provided on their outsides, i.e., the sides facing away from the core 5, with a protective foil 13, such as, in particular, an aluminum foil 14. Such a protective film 13 and, in particular, an aluminum foil 14, has the advantage that, during the production and connection of a cover layer 11 to the chamber walls 4, the corresponding, mold in which the connection step finally takes place is protected, in particular, from resin material contained in the cover layers 11, so that absolutely no undesired adhesion of such resin material to the mold can take place. Furthermore, such protective foils or layers 13 could form an effective diffusion barrier against the penetration of air into the vacuum chambers 3. Even for the use of an aluminum foil 14 or the like, an additional advantage is also achieved in that this is used with its glossy surface as a reflection barrier for IR radiation, wherein the insulation power of the vacuum insulation panel 1 is also increased.
The heat transfer takes place in the conventional insulation materials known from the practice by means of so-called framework conduction, gas conduction, and radiation conduction. The gas conduction is the largest portion, ca. ⅔ of the entire heat conduction. In order to eliminate this portion, modern heat-insulation materials are evacuated, wherein gas conduction is eliminated at least to a large degree. The radiation conduction is stopped by means of reflective surfaces that reflect IR radiation.
Even in the vacuum insulation panels according to the invention, the air is evacuated, wherein gas conduction is eliminated. For the corresponding construction with the aluminum foil 14 as protective foil 13, IR radiation is prevented by means of the high-gloss surface. What is left is framework conduction that is calculated from the heat conductivity of the base material and its mass.
In the presently discussed embodiment, the core 5 of the vacuum insulation panel 1 is made from so-called hard paper. Hard paper has, according to the reinforcement material that is used, 0.1-0.2 W/mK with respect to one cubic meter. The core with the chambers 2 weighs 30-60 kg/m³, depending on the size of the chambers. From this the framework, portions are given with respect to cubic meters, as was already explained above, with a ratio of, for example, ca. 1:17 to approximately 1:33, wherein these are advantageous values. The thermal conductivity of a hard paper used as an example with the already discussed values of 0.1-0.2 W/mK leads to the result of values for the framework conduction of the vacuum insulation panels 1 of, for example, 0.0058-0.0117 W/mK up to, e.g., 0.0029-0.0058 W/mK.
A significant aspect for vacuum insulation panels 1 is the diffusion of air into evacuated hollow spaces. The vacuum insulation panels 1 are subject to a constant gas pressure that attempts to create a pressure balance between the atmosphere and the vacuum prevailing in the chambers 3 of the vacuum insulation panels 1.
Vacuum insulation panels known from practice are made from a foam core, a protective fleece, and a plastic barrier foil, usually coated with aluminum. Due to its small layer thickness, this barrier foil represents only little protection against diffusion. In vacuum insulation panels known from practice, it is attempted to balance out this deficiency through special barrier foils. Another disadvantage of the known vacuum insulation panels is that they are made from only one vacuum chamber, because the foam core is produced from an open-pore foam, and thus pressure equalization acts simultaneously on the entire system.
The special construction of the vacuum insulation panels 1 according to the present invention here has very decisive advantages, because the pressure is loaded, in general, only on the outer chambers 3 or honeycombs lying at the edge 15 between the cover layers 11. Because the individual chambers 3 are sealed from each other, a pressure balance must first take place in these outer chambers 3 and must then propagate successively inward. This advantage is achieved in that the core 5 of the vacuum insulation panels 1 according to the invention is made from many individual chambers 4 in which air can penetrate only one after the other from the edge 15 between the cover layers 11. In order to further stop this effect, preferred configurations provide that the core 5 is sealed tight, with respect to diffusion at its free edges 15 between the cover layers 11, with artificial resin, such as, for example, artificial resin body filler or the like.
The air pressure also acts on all chambers 4 simultaneously by means of the cover layers 11. Here, the vacuum insulation panels 1 according to corresponding special constructions are especially protected, wherein cover layers 11 of these panels are not made, as is otherwise typical, from a thin sensitive plastic foil, but instead from an, in particular, ca. 1 mm-thick reinforced epoxy resin layer 12 that could also be provided with an aluminum foil 14 as a protective layer 13, as FIG. 2 shows. As an alternative to the aluminum foil 14, a high-barrier film could also be the protective layer 13 or form a component thereof. Instead of the construction as a film, the protective layer 13 could also be realized as a coating.
Below, a few production processes or steps will be discussed in greater detail, within the scope of which additional device features of the vacuum insulation panel 1 will also be specified or illustrated.
In a chamber press station K (see FIG. 4), the plates 7 are pressed that form, in cross section, half-chambers 6 and from which the core 5 is later assembled. The material of the walls 4 or intermediate walls of the chambers 3 or, expressed differently, of the core 5, is made in the shown embodiment from kraft paper that is coated with a melamine-phenolic resin derivative. The resin cures under a pressure of 30 bar and a temperature of 185° C. in ca. 6 s. The advantage of the resin is that the linking takes place only as long as energy is supplied. Thus, the resin could be dried without curing completely. The wall material is delivered ready for further processing and is dry in contrast to other resin systems, and undergoes a curing reaction only under pressure and heat. The linking process is completed within ca. 6 s. Subsequent outgassing no longer takes place. Another advantage of this material is that it is economical and can be stored as a raw material without problems for a long time.
The walls 4 of the chambers 3 are ca. 0.5 mm thick and have dimensions of 10 mm, from which a material length of 49.6 mm for each chamber 3 is given for the walls 4. These values are to be understood as examples and could vary according to construction and requirements.
In order to keep the required pressing force from becoming too high in a press P being used, for example, five half-chambers 6 are pressed simultaneously in one plate 7. In order to eliminate the need to stretch the wall material, the material is advantageously preshaped. For example, the material is flexible at 60° C. and can be deformed with little pressure, which is why a heat emitter W is used at the beginning of the chamber press station K. As an alternative to the heat emitter W, the pressing tool could also be heated. Because the preshaping could furthermore take place very quickly and requires little pressure, a simple prepress VP with a pneumatic cylinder PZ could be used and driven. From the prepress VP, a preplate 7′ is obtained that is completed to form the plate 7 in the subsequent pressing step. One example of this process section is shown schematically in FIGS. 3 and 4. Accordingly, the entire pressing process combines the heating of the paper, the preshaping, and the actual pressing.
The plates 7 produced in this way, with the cross-sectional shape of half-chambers 3, are fed to an automatic core or block adhesion device (not shown) in which these plates 7 are bonded evenly to form a block 16 that could also be designated as a honeycomb block or chamber block. In FIG. 5 it is shown schematically how two such plates 7, are shown only in section, are placed one on top of the other, in order to be able to connect to each other at their contact points 8 in a rigid and gas-tight fashion while forming the chambers 3, wherein this connection could be realized through adhesion or fusing or in some other suitable way.
For example, the points coming into contact with each other or contact points 8 of two plates 7 arranged one on top of the other are provided with a fast-curing adhesive that is deposited, for example, by an automatic device. In practice, the adhesive is deposited on the individual plates 7 before they are brought into contact with each other and thus are bonded to each other quickly and with good effect. These steps are repeated until a sufficient number of plates 7 are rigidly connected to each other to form a block 16.
Instead of the adhesion of plates 7 into a block 16, the latter could also be formed by fusing plates 7, for example, in a press (not shown).
Such a block 16 that is to be seen, for example, with example dimensions in FIG. 6, is then transported to a saw (not shown). From the block 16, chamber discs 17 are then cut perpendicular to the plates 7 according to the panel thickness desired later, i.e., under consideration of the thickness of the cover layers 11 still to be deposited. The chamber discs 17 correspond directly to the cores 5 of the vacuum insulation panels 1 produced in this way.
In the next production processing step, the chamber discs 17 are provided with the cover layers 11 and, for example, a vacuum is generated in the chambers 3. As was already specified further above, a filling of the chambers 3 with selected gas material would also take place here. The process of depositing the first cover layer 11 and also the second cover layer is shown schematically in FIGS. 7 and 8; for details refer to these sequences.
According to FIG. 7, in step S1, the protective foil 13, for example, the aluminum foil 14, is placed in a mold F. In step S2, the reinforced resin layer 12 is placed on the protective foil 13. On this layer, in step S3, a chamber disk 17 or the core 5 is placed, whereupon the mold F is closed with a cover D and the air is drawn out from the interior of the mold F closed with the cover D (step S4). The cover D is loosely covered with a rubber blanket G toward the inside of the mold F, so that the evacuation of the inside of the mold F and an inflow of air between the cover D and the rubber blanket G presses the latter against the free side of the core 5 and thus this core onto the reinforced resin layer 12 that is here also simultaneously pressed onto the protective layer 13, as shown in step S5. Here, the core 5 is rigidly pressed into the wet resin of the cover layer 11. This state is maintained until the resin of the cover layer 11 is cured. In step S6, after this curing, air can flow back into the inside of the mold F and, after opening the cover D, the composite made from the core 5 with the first cover layer 11 can be removed.
Then as shown in FIG. 8, the protective film 13, for example, the aluminum foil 14, is placed in a mold F′ in step S11. In step S12, the reinforced resin layer 12 is placed on the protective foil 13. On this layer, in step S13, the composite made from the core 5 with the first cover layer 11 is placed, whereupon the mold F′ is closed with a cover D′ and the air is drawn out from the inside of the mold F′ closed with the cover D′ (step S14). The cover D′ is loosely covered with a rubber blanket G′ toward the inside of the mold F′, so that the evacuation of the inside of the mold F′ and an inflow of air between the cover D′ and the rubber blanket G′ presses the latter against the free side of the composite made from the core 5 with the first cover layer 11 and thus presses this composite onto the reinforced resin layer 12 that is simultaneously also pressed onto the protective layer 13, as shown in step S15. Here, the composite made from the core 5 with the first cover layer 11 is pressed rigidly into the wet resin of the second cover layer 11. This state is maintained until the resin of the second cover layer 11 is cured. After this curing, in step S16, air can flow back into the inside of the mold F′ and, after opening the cover D′ the completed vacuum insulation panel 1 can be removed from the mold F′. Then the vacuum insulation panel 1 could be cut into any shape.
In FIGS. 9 and 10, an alternative embodiment is shown schematically, in a section view and a perspective view, respectively, for the construction of the chamber core 5 with a design. In this design, semicircular chambers 3′ and cross-shaped chambers 3″ are produced with which a favorable combination is achieved for low heat conduction via the walls 4 between the cover layers 11. With respect to the diagram in FIGS. 9 and 10, for producing the chamber core 5 for a vacuum insulation panel 1 as in the previously described embodiments of the production process, discs are cut (in the diagram of FIG. 10, even and parallel to the surface of the sheet of the drawing) from a block-like preproduction stage.
With respect to the construction of the design of the chambers, other variants are also possible. Thus, hemispheres (not shown) that are equal to each other could be arranged on one side in a plane in the same orientation. A second layer of hemispheres that are equal, in turn, to each other and to the hemispheres of the first layer could then be arranged on top, so that a hemisphere of the first layer and a hemisphere of the second layer contact at exactly one point. The cover layers are attached to the open sides of the hemispheres. Thermal conduction must take place and then can take place only via the contact points of the hemispheres, which means significantly less material. This version is not limited to hemispheres, but instead functions with any coupling-like shape that could also be correspondingly flat according to the small thickness of the vacuum insulation panel 1, such as spherical segments or segments of spherical bodies or other coupling-like formations. Such designs could be produced, for example, through injection molding, deep drawing, and other known techniques both in preproduction stages, for example, individual first and second layers, or as a complete core in a single process.
With respect to the material pairing for the material of the core 5, all combinations are advantageous that result in an optimization of the lowest possible heat conduction. These include others in addition to the already-named material pairing consisting of paper and a melamine/phenolic resin derivative. If the organic material of paper or wood is replaced by an inorganic substance, such as fiberglass matt material, then the heat conduction is reduced. For the material of the core 5, a pure ceramic base material is also conceivable, that is, a combination of several materials is not absolutely necessary.
The invention is shown as an example with reference to the embodiments in the description and in the drawing and is not limited to, but instead includes, all variations, modifications, substitutions, and combinations that someone skilled in the art could take from the present document, in particular, in the scope of the claims and the general statements in the introduction of this description and also from the description of the embodiments, and could combine with his technical knowledge and also with the state of the art. In particular, all of the individual features and construction possibilities of the invention and its embodiments could be combined.

Claims

1. Vacuum insulation panel with a core with insulating hollow spaces and also cover layers closing the core in a tight fashion relative to the surroundings,

wherein the hollow spaces of the core are formed by chambers, wherein these chambers are closed gas-tight relative to each other and reach, together with their walls or intermediate walls, from a cover layer to the other cover layer, and are formed from the walls or intermediate walls and the cover layers.

2. Vacuum insulation panel according to claim 1,

wherein the walls or intermediate walls of the chambers form a honeycomb structure.

3. Vacuum insulation panel according to claim 2,

wherein the honeycomb structure is rectangular, hexagonal, or octagonal, contains circular shapes, or is regular or irregular.

4. Vacuum insulation panel according to claim 1,

wherein each cover layer is made from a gas-tight material or is coated with a gas-tight material.

5. Vacuum insulation panel according to claim 1,

wherein each cover layer contains a layer or plate made from, in particular, reinforced epoxy, melamine, or phenolic resin or the like in direct contact with the walls or intermediate walls of the chambers.

6. Vacuum insulation panel according to claim 5,

wherein the reinforcement of the cover layer contains fiberglass material, kraft paper, sisal or the like.

7. Vacuum insulation panel according to claim 1,

wherein each cover layer has a protective layer on its side facing away from the walls or intermediate walls of the chambers.

8. Vacuum insulation panel according to claim 7,

wherein the protective layer contains a reflective high-barrier film or an aluminum foil or a high-barrier coating or aluminum coating or the like.

9. Vacuum insulation panel according to claim 1,

wherein each cover layer has a thickness greater than approximately 0.5 mm, advantageously greater than ca. 1 mm, and especially preferred approximately 1 mm.

10. Vacuum insulation panel according to claim 1,

wherein the walls or intermediate walls of the chambers are made from a gas-tight material or are coated with a gas-tight material.

11. Vacuum insulation panel according to claim 1,

wherein the walls or intermediate walls of the chambers contain paper or cellulose and/or the walls or intermediate walls of the chambers have a coating with melamine resin, phenolic resin, or a melamine resin-phenolic resin derivative and/or the walls or intermediate walls of the chambers contain kraft paper or hard paper, in particular, with reinforcement.

12. Vacuum insulation panel according to claim 1,

wherein the walls or intermediate walls of the chambers contain a metallic foil or are coated with a metallic layer.

13. Vacuum insulation panel according to claim 1,

wherein the walls or intermediate walls of the chambers exhibit, with respect to one cubic meter, thermal conductivity of less than ca. 0.3 W/mK, advantageously less than approximately 0.2 W/mK, and especially preferred less than approximately 0.1 W/mK.

14. Vacuum insulation panel according to claim 1,

wherein the walls or intermediate walls of the chambers have a thickness of approximately 0.5 mm.

15. Vacuum insulation panel according to claim 1,

wherein a vacuum of approximately 98% prevails in the chambers.

16. Vacuum insulation panel according to claim 1,

wherein a heat-insulating gas, for example, argon or another noble gas or a corresponding gas mixture is contained in the chambers.

17. Vacuum insulation panel according to claim 1, wherein the core is sealed with artificial resin or the like at its free edges between the cover layers.

18. Method for the production of a vacuum insulation panel according to claim 1,

wherein a) first, plates are produced that have, in cross section, the shape and arrangement of walls of half-chambers connected to each other but are significantly longer than the height of the walls of the chambers,

b) then a composite is produced in which, on a first such plate, another such plate is placed so that whole chambers are formed,

c) then the plates are connected to each other in a permanent and gas-tight fashion at their contact points,

d) then additional plates are placed according to step b) one after the other onto the uppermost plate of the composite and are connected in a permanent and gas-tight fashion to the uppermost plate of the composite according to step c),

e) then the composite is cut perpendicular to the plates into chamber discs with the desired thickness corresponding to the intended chamber height, and

f) finally, the chamber discs are connected in a permanent and gas-tight fashion to the cover layers on the open sides of the chambers.

19. Method according to claim 18, wherein the cover layers are connected to the corresponding chamber discs one after the other and that the second cover layer is connected to the assembly made from the chamber discs and the first cover layer at a low pressure, in a vacuum, or in a gas atmosphere with a gas that is provided as a filling for the chambers.

20. Method according to claim 18,

wherein the cover layers are simultaneously connected to the corresponding chamber discs and that the cover layers are connected to the chamber discs at a low pressure, in a vacuum, or in a gas atmosphere with a gas that is provided as a filling for the chambers.