DE102009038461B4 - Thermal insulation element and method for its production - Google Patents

Abstract

Thermal thermal insulation element comprising at least two layers (2, 2A, 2B, 2C, 2E, 2F), wherein:
- The layers (2, 2A, 2B, 2C, 2E, 2F) each of a plurality of strands (3, 3A, 3B, 3C, 3D) are formed, which are arranged approximately parallel to each other and connected to each other in a plane, characterized marked that
- the strands (3, 3A, 3B, 3C, 3D) are each formed from a plurality of hollow, at least partially evacuated elongated cells (4A, 4B, 4C) arranged in a row one behind the other and separated from each other by constrictions (5A, 5B) and the cells (4A, 4B, 4C) of one layer (2, 2A, 2B, 2C, 2E, 2F) to the respective adjacent cells (4A, 4B, 4C) of an adjacent layer (2, 2A, 2B, 2C, 2E, 2F) are arranged offset in layer plane,
- wherein the cells (4A, 4B, 4C) are made of glass and assembled during curing in such a way that each cell (4A, 4B, 4C) with the cells of the adjacent strands (3A, 3B, 3C, 3D) of the same layer and the cells of the adjacent layers (2A, 2B, 2C, 2D) are directly connected.

Description

Field of the invention

The invention relates to a thermal thermal insulation element of low thermal conductivity, for example for thermal insulation or thermal insulation of buildings or technical equipment, with multicellular, individually sealed, evacuated cavities and a method for producing such thermal insulation elements.

Background of the invention

Thermal insulation elements are used in many areas from the refrigerator to the thermal insulation of space capsules. Due to the need for energy savings in heating and cooling energy consumption of houses, buildings and refrigerators and freezers and rooms highly efficient heat-insulating sheaths are necessary and useful.

The amount of heat transferred from a warmer area to a colder area in a given period of time is called a heat flow. The heat flow through a solid depends on its thermal conductivity. The thermal conductivity of a solid results from its length, the passage area of the heat flow and a material-specific thermal conductivity λ. In this case, the thermal conductivity for a solid at a minimum passage area and / or a maximum path length for the heat flow through the solid body is minimal. In addition to the heat conduction in the interior of the solid, heat is released outside the solid by convection, ie the transport of molecules, and heat radiation of the solid. Thermal insulation or insulation means reducing at least one of these effects.

In homes, buildings, refrigerators and freezers and rooms nowadays readily available and large-scale cost-effective insulation materials, which have low thermal conductivity are used. One representative of these materials is polystyrene (Styropor ™). This consists essentially of foam balls filled with gases or air. Other low thermal conductivity materials used for thermal insulation purposes are mineral wool and fibers, hollow fibers, perlites, as well as natural or biological materials such as mineral wool. New wool or straw. With these materials, a thermal conductivity λ of 0.03 to 0.08 W / (mK) is typically achieved. The low thermal conductivity is based on the one hand on the low thermal conductivity of the framework itself, but on the other hand, significantly on the low thermal conductivity of the enclosed gas. In the case of most conventional insulation materials, air is trapped. Air has a thermal conductivity of λ ≈0.0261 W / (mK). In order to reduce the thermal conductivity of the insulating material in addition to the optimization of the framework material, the thermal conductivity of the trapped gas must be reduced.

A gas with very low thermal conductivity is carbon dioxide (λ ≈ 0.015 W / (mK)), which is therefore often used in high-damping materials. A permanent inclusion in, for example, foamed plastics is difficult because it comes to the outdiffusion of the gas over time. At present, many efforts are being made to further reduce the thermal conductivity of thermal insulation materials.

A technologically sophisticated approach is to reduce the number of gas molecules by creating a vacuum. "Evacuated" or "vacuum" means that a fluid in a volume, for example in one of the cells 4A . 4B . 4C , of the has a pressure which is significantly lower than the atmospheric pressure under normal conditions. It may be a rough vacuum at 10 ⁵ to 10 ² Pa, a fine vacuum of 10 ² to 10 ^-1 Pa, a high vacuum of 10 ^-1 to 10 ^-4 Pa or even an ultra-high vacuum of less than 10 ^-4 Pa act.

A known embodiment of such a vacuum insulation is to evacuate the cavity of a double-walled container. This is used for example in thermoses or Dewar vessels. The double-walled cavities, the walls of which are a few millimeters apart, usually consist of glass or stainless steel surfaces and have no supporting structures. Residual pressure is in the range of 10 ^-1 Pa. Due to the lack of support core mainly rotationally symmetric container can be realized. In such vacuum-insulated structures without support core, the edge losses via the contact points of the two parts of the double jacket make up the largest part of the heat losses.

In the early 1990s, there were activities in the USA for the development of insulating materials based on partially evacuated glass microspheres (cf. US 5 500 287 A and US 5 501 871 A ). To the best of our knowledge, there are no commercial products based on these patents.

The other possibility of vacuum insulation is the use of a support core. Such an evacuated body with low thermal conductivity for thermal insulation is known as vacuum insulation panel (Vacuum Insulated Panel, short VIP) known (eg DE 1 434 758 A . DE 38 28 669 A1 ). It consists of a porous core material and a sufficiently gastight envelope. The core material serves as a support body and the shell prevents the gas entry into the insulation board. With such materials, thermal conductivities of about 0.004 W / (mK) can be realized. This value is by a factor compared to conventional insulation materials (eg polystyrene) 5 - 10 lower. Due to the ecological and economic advantages, a great development and market potential is seen for vacuum insulation panels, in particular for insulation in house construction, especially after Passivhausstandart.

So far, the production of these materials is expensive and therefore the associated price is high. In addition, such an insulating board is very sensitive to mechanical damage. No matter how small damage in the airtight shell at any point can penetrate ambient air and thus leads to a massive increase in the thermal conductivity of the entire insulation board. Even when laying these panels damage can easily occur and these are not easily detected in the installed state. Another disadvantage of the VIPs is that the high insulation value is achieved only theoretically. In practice, joints in the millimeter range occur during laying, which can not be completely avoided. Such joints already cause significant unwanted thermal bridges.

As a problem with the current state of the art of vacuum insulation panels is also seen that the long-term stability of the hermeticity of the envelope can not be guaranteed easily over decades. When the shell of a vacuum insulation panel is damaged, the vacuum collapses and the thermal conductivity of the panel drastically increases, making it virtually unusable. Especially in house building a stability of the vacuum over well over 20 years is desired.

A solution to this problem provides the patent US 4,468,423 , It discloses a thermal insulation element which is composed of a plurality of individually evacuated chambers. The chambers are initially each an opening to be sucked by the gases contained; after suction, the opening is closed. In one example, multiple layers of such chambers are stacked.

Another approach is in patent US 3,769,770 disclosed. It describes a thermal insulation element with hollow fibers whose interior is evacuated. The hollow fibers are intertwined and coated with a reflective material.

DE 10 2004 026 894 A1 further discloses a heat-insulating mat according to the preamble of claim 1, wherein a porous insulating material of silica or polystyrene or polyurethane foam is disposed in a cladding film, wherein individual evacuated areas are separated from each other gas-tight. The individual areas are evacuated after the insulation has been arranged, then the areas are each closed. Several mats can be layered.

The font DE 29 54 563 C2 describes a cover for a solar collector. The cover has vacuum microballoons for thermal insulation. The microballoons in one embodiment are embedded in multiple layers in a polyolefin or polyester foam.

The present invention is based on the object, heat insulation elements of the type mentioned but to further improve.

The invention provides a thermal insulation element according to the subject of independent claim 1 ready.

The invention also provides a method for producing a thermal insulation element according to the subject-matter of independent claim 18.

Further aspects and embodiments of the invention will become apparent from the dependent claims, the following description and the drawings.

In one embodiment, the cells are made of glass.

In an alternative embodiment, the cells are made of plastic.

In another embodiment, the cells are configured approximately tubular.

The at least partially evacuated cells may also be filled with an insulating material according to a further embodiment.

In another embodiment, a cross-section of the at least two superposed layers has a pattern of regular hexagons.

In a further embodiment, the heat-insulating element further comprises at least one infrared-reflective coating.

In a particular embodiment, the infrared-reflective coating is disposed between the layers.

In a further embodiment, the heat-insulating element is permeable to light in the visible range.

In a further embodiment, the thermal insulation element further comprises a layer for protection against mechanical stress.

In a further embodiment, the thermal insulation element is configured to enter into a connection with a facade coating.

In a particular embodiment, the thermal insulation element has at least four layers.

In a further embodiment, in each case at least two adjacent layers are each combined in a layer packet in which the constrictions of the layers are arranged at equal intervals, wherein adjacent constrictions of different layers are arranged in a constriction perpendicular to the strand direction, and offset the constricting planes of adjacent layer packets to each other are arranged.

In one embodiment, gaps between the cells are evacuated.

In one embodiment, a thermal insulation effect depends on a direction of a temperature gradient.

In a further embodiment, the heat-insulating element at lateral edges on a connection profile for the positive connection with an adjacent thermal insulation element.

In an alternative embodiment, the thermal insulation element on lateral edges on a coating for thermally insulating connection with an adjacent thermal insulation element.

In a further embodiment, the thermal insulation element is combined with a photovoltaic element or a solar collector.

In one embodiment, a layer is formed from a plurality of strands, in which the strands are connected and extend approximately parallel to each other and in which each strand is adjacent to at most two further strands.

In one embodiment, the layer is adapted to the shape of a body to be insulated.

In a particular embodiment, the layer is rolled up into a tubular thermal insulation element.

In another embodiment, at least two layers are stacked.

In a further embodiment, the constrictions of the strands of one of the at least two layers to the constrictions in a further layer are arranged staggered in strand direction.

In a particular embodiment, the at least two layers are divided into uniform sections.

In a particular embodiment, the at least two layers are divided into uniform sections in such a way that they have a connection profile at lateral edges for a positive connection with an adjacent thermal insulation element.

In one embodiment, the at least two layers form a thermal insulation element.

In one embodiment, the strands are arranged parallel to a pipeline. They serve in the form of a pipe jacket the insulation of the pipe and could be used for insulation requirements in pipeline construction and in solar thermal energy.

In a further embodiment, one or more layers on the inside or outside are provided with a photovoltaic layer.

In a further embodiment, the thermal insulation element is removed through a vacuum lock from the evacuated chamber.

list of figures

• 1 eine perspektivische Ansicht eines Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit mehreren Zellen;
• 2 eine perspektivische Ansicht eines weiteren Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit mehreren Zellen und einer ebenen Querschnittsfläche;
• 3a eine Querschnittsansicht eines weiteren Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit Zellen mit rundem Querschnitt;
• 3b eine Querschnittsansicht eines weiteren Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit sechseckigen Zellen;
• 3c eine Querschnittsansicht eines weiteren Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit achteckigen Zellen; und
• 4 eine perspektivische Ansicht eines Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit aufeinanderliegenden Schichten, die Schichtpakete bilden.
• 5 eine perspektivische Ansicht eines Ausführungsbeispiels eines erfindungsgemäßen Wärmedämmelements mit aufeinanderliegenden Schichten umgeben von einer Schutzstruktur sowie einer Falz als Verbindungsprofil zur formschlüssigen Verbindung mit einem benachbarten Wärmedämmelements zur Reduktion von Wärmebrücken.

Further features, advantages and details of the invention will become apparent from the following description of preferred embodiments of the invention and from the drawing. Here are shown schematically:

• 1 a perspective view of an embodiment of a thermal insulation element according to the invention with a plurality of cells;
• 2 a perspective view of another embodiment of a thermal barrier elements of the invention having a plurality of cells and a planar cross-sectional area;
• 3a a cross-sectional view of another embodiment of a heat-insulating element according to the invention with cells with a round cross-section;
• 3b a cross-sectional view of another embodiment of a heat-insulating element according to the invention with hexagonal cells;
• 3c a cross-sectional view of another embodiment of an inventive heat-insulating element with octagonal cells; and
• 4 a perspective view of an embodiment of a heat-insulating element according to the invention with superposed layers, the layer packages form.
• 5 a perspective view of an embodiment of a thermal insulation element according to the invention with superimposed layers surrounded by a protective structure and a fold as a connection profile for positive connection with an adjacent heat-insulating element for the reduction of thermal bridges.

The drawing is not necessarily to scale. Some parts are only shown schematically. Attention was paid to the principle of the invention.

Description of the preferred embodiments

1 shows a perspective view of an embodiment of a thermal insulation element according to the invention with four layers 2A . 2 B . 2C . 2D Of course, a multiple of these may be contained in a thermal insulation element as needed. The layers 2A . 2 B . 2C . 2D are approximately parallel and border each other. every layer 2A . 2 B . 2C . 2D includes several strands, exemplified with 3A . 3B . 3C . 3D designated. The strands 3A . 3B . 3C . 3D a layer 2A . 2 B . 2C . 2D are approximately parallel to each other. In the illustrated embodiment, the strands 3A . 3B . 3C . 3D a layer 2A . 2 B . 2C . 2D also approximately parallel to the strands of the adjacent layers. Every strand 3A . 3B . 3C . 3D comprises several cells, by way of example with 4A . 4B . 4C designated. The cells 4A . 4B . 4C in a strand 3A . 3B . 3C . 3D are arranged in a row, ie every cell 4A . 4B . 4C has in the same strand 3A . 3B . 3C . 3D at most two adjacent neighboring cells. The cells 4A . 4B . 4C are approximately tubular, that is, their dimension in Strangrichtung is greater than their dimensions transverse to the strand direction. The cells 4A . 4B . 4C are respectively evacuated or at least partially evacuated, ie in the cells there is a pressure of about 10 ² Pa. Every cell 4A . 4B . 4C is individually gas-tight, ie, a gas exchange between the cells 4A . 4B . 4C or between a cell 4A . 4B . 4C and an environment does not take place.

The anisotropic elongated geometry of the structure also causes anisotropy of the thermal conductivity in the ratio of about 2: 1. The main insulating effect is given perpendicular to the element structure. The strands 3A . 3B . 3C . 3D Therefore, run approximately at right angles to a thermal insulation direction, wherein the thermal insulation direction for the field of application describes the mean direction of heat flows through the thermal insulation element when used as intended. The thermal insulation direction thus runs approximately parallel to a gradient of the temperature in the region of the heat-insulating element 1 ,

The cells 4A . 4B . 4C form a regular or irregularly arranged structure and are individually evacuated. This is the thermal insulation element 1 composed of individual mutually thermally independent cells. In the case of a mechanical effect on the component, such as a shock, drilling a hole or penetrating sharp objects (eg by a nail), only locally damaged cells and lose only their highly insulating properties. The thermal insulation element 1 as such, it will continue to function. Such damage would in comparison with a vacuum insulation panel, as it is commonly used in construction at the time of application, bring about a breakdown of the thermal insulation of the entire vacuum insulation panel, ie the thermal conductivity would rise to the level of an ambient fluid.

2 shows a perspective view of another embodiment of a thermal insulation element according to the invention 1 , In the illustrated embodiment, each strand 3A . 3B . 3C . 3D a round cross-section. every layer 2A . 2 B . 2C . 2D is half the strand width to the adjacent layers 2A . 2 B . 2C . 2D offset so that, for example, the strands 3A . 3B . 3C the layer 2D one border each 6A . 6B . 6C between two strands of the adjacent layer 2C cover. Every cell 4A . 4B . 4C is with the cells 4A . 4B . 4C the neighboring strands 3A . 3B . 3C . 3D the same layer and the adjacent layers 2A . 2 B . 2C . 2D mechanically connected. The positioning of the strands is similar to the positioning of hexagons of a regular hexagon pattern, as is known from honeycombs.

By arranging these individual evacuated cells 4A . 4B . 4C in the manner of a honeycomb structure, at which the cells 4A . 4B . 4C in the strands 3A . 3B . 3C . 3D are mechanically connected to adjacent cells, receives the thermal insulation element 1 in addition to the thermal insulation effect a very high mechanical stability. Thus, it is basically conceivable that the thermal insulation element 1 In addition to its thermal insulation effect can also assume a structural-static function.

In 1 and 2 close constrictions 5A . 5B the cells 4A . 4B . 4C in a strand 3A . 3B . 3C . 3D against each other. The cells are arranged in one embodiment so that the constrictions 5A . 5B not for all cells 4A . 4B . 4C are arranged at the same height, but that the constrictions 5A . 5B offset to the constrictions 5A . 5B be arranged in the adjacent strands and / or layers. This arrangement reduces heat flows through the thermal insulation element 1 :

In the thermal insulation element 1 occurs a heat flow substantially along the cell walls, as in the interior of the cells by the vacuum, a heat flow is minimal. The thermal conductivity of the thermal insulation element 1 is therefore essentially dependent on the thermal conductivity of the cell walls and the geometry of the thermal insulation element 1 influenced, namely by a heat flow through the surface and a path length through the thermal insulation element 1 , To reduce the heat flow, the cell walls are not only made as thin as possible, the staggered arrangement of the cells also extends the average path length through the heat-insulating element 1 in relation to the thickness of the thermal insulation element 1 , which reduces a relative heat conductivity.

The constrictions 5A . 5B offer a path through the heat-insulating element, which has a higher thermal conductivity, as a way exclusively along the lateral cell walls. The first reason is that when constricting the hollow strands, the cell walls are pulled together and the strands are shortened slightly, so that in the area of constrictions 5A . 5B more material in relation to the surface of the thermal insulation element in the area of the constrictions 5A . 5B As a result, the passage area is increased in relation to the heat-insulating element surface.

In the embodiment in 1 and 2 are the constrictions 5A . 5B the layer 2D also in the vicinity of the constrictions of the next but one layer 2 B arranged. Between these constrictions are cell walls of adjacent strands of the intervening layer 2C , This results along these constrictions and the cell walls, an approximately rectilinear and therefore relatively short path through the thermal insulation element 1 , whereby a thermal conductivity is increased in this area. In a particular embodiment, therefore, the constrictions are arranged in three successive layers each offset from the other two layers, so that such short paths through the thermal insulation element 1 be avoided.

3a shows a cross section of a further embodiment of a thermal insulation element according to the invention 1 with six layers 2A - 2F from strands 3 with round cross section. The thermal insulation element 1 indicates its outer layers 2A . 2F one cover each 8A . 8B on top of the cells of the heat-insulating element 1 protects against mechanical stress. Due to the round cross section of the strands 3 can the strands 3 a volume of thermal insulation element 1 do not fill completely. It is therefore located between the strands 3 interspaces 7 , The gaps 7 extend along the strands 3 and form a passage for fluids. As in the 1 and 2 can be seen, are also about the constrictions 5A . 5B free areas. The free areas around the constrictions 5A . 5B form in conjunction with the interstices 7 a passage for fluids that spread over several layers 2A - 2F extends. As well as the fluids in these spaces 7 and the free areas around the constrictions 5A . 5B are suitable to transfer heat by convection, in one embodiment, the spaces 7 and / or the free areas around the constrictions 5A . 5B at least partially blocked for fluid transport and evacuated, allowing a heat flow through the interstices 7 is prevented. Blocking in a particular embodiment are designed so that a heat conduction through the blocks remains minimal. The blockages are as thin as possible in this embodiment and made of a material with a low thermal conductivity.

Also in this variant, it is basically conceivable that the thermal insulation element 1 In addition to its thermal insulation effect can also assume a structural-static function.

In another embodiment, the spaces are 7 the thermal insulation element 1 filled with a solid having low thermal conductivity to prevent convection through the thermal insulation element.

In a further embodiment, not shown, the constrictions surround the strands 3 not complete, but are only as depressions on one side or on two opposite sides of the strands 3 formed so that the diameter of the strands 3 Partially preserved even in the area of constrictions. at a suitable orientation about the longitudinal axis of the strands 3 the layers are thus impermeable to fluids in the heat-insulating direction.

3b shows an alternative embodiment in which the cross section of a strand 3 is about hexagonal, giving the volume of a heat-insulating element 1 from the strands 3 is filled in and spaces 7 between the strands 3 are minimal or avoided. In one embodiment, a heat flow along the free areas around the constrictions is prevented by arranging all the constrictions such that the free areas of the constrictions are not in fluid-permeable communication with each other. Although the free areas are evacuated around the constrictions, a heat flow along the constrictions is largely prevented. The areas where the strands 3 touch are greatly increased in this arrangement. This gives the structure additional stability, but it also increases a contact surface along which a heat flow over several layers through the thermal insulation element 1 spreads.

Since each wall in the area of the contacting surfaces is formed by the walls of two cells, these walls are twice as thick as the cell walls of a single strand 3 , Therefore strands can be used for this area 3 be used with further reduced wall thickness.

If the wall thickness of the cells of a structure having round cross sections is reduced to a technically possible minimum, without thereby falling below a required mechanical strength, it may optionally be calculated and / or tested whether this structure offers better thermal resistance than a structure with a hexagonal cross section , It depends on various parameters. For example, an increased contact surface between strands increases 3 superimposed layers, the thermal conductivity of the thermal insulation element 1 , Also the blockages or the solid to seal the gaps 7 contributes in such embodiments to a heat conduction along the heat-insulating direction.

Other embodiments for the cross section of a heat-insulating element 1 are also conceivable. In 3c has a thermal insulation element I cells with a cross-sectional pattern of regular octagons. Such a cross section arises, for example, when superposed strands 3 not offset but arranged in thermal insulation direction each other. This arrangement results in the same thickness of the individual layers to a thicker thermal insulation element 1 , A thicker thermal insulation element 1 is basically better suited to a bending load of the thermal insulation element 1 to suffer. In addition, the number of spaces 7 between two layers 2 diminished, leaving fewer gaps 7 need to be blocked. Also the number of contact points between two layers 2 is lower than in a staggered structure, which provides thermal resistance of the thermal insulation element 1 basically increased.

4 shows a further embodiment of an arrangement of several layers, in which each three successive layers thermal insulation elements or layer packages 20A . 20B . 20C form. In every shift package 20A . 20B . 20C For example, all constrictions are approximately equidistant, and adjacent constrictions of different layers are each about at a constriction level 50A . 50B . 50C arranged perpendicular to the strand direction in constriction groups. In the middle layer package 20B is the constriction level 50C offset to the constriction levels 50A . 50B of the outer layer package 20A arranged. In this embodiment, short paths through the thermal insulation element 1 avoided in the area of constrictions, as on a straight path through the thermal insulation element 1 along the constrictions not only lie the boundaries between two strands, but also each at least one strand is superimposed on the border. In this embodiment, since the constrictions of multiple layers are located at the same locations, it is easier to produce than embodiments in which the locations of the constrictions for each layer deviate from adjacent layers.

5 shows a detail of the perspective view of another embodiment of a thermal insulation element according to the invention 1 consisting of several sub-elements. The thermal insulation element 1 Here, by way of example, has nine layers 2A - 2A , each grouped in three groups, made of strands 3 each consisting of a plurality of closed cells 4 on. Between the shift 2C and the layer 2D as well as between the layer 2G and the layer 2H is an infrared reflecting layer 9 arranged. The outside of the thermal insulation element 1 is with a protective layer 10 envelops. This has, for example, predominantly two functions: First, it provides mechanical protection of the layers, on the other hand, it allows a simple mechanical processing or installation of the elements. To minimize thermal bridges caused by air gaps between adjacent elements is the thermal insulation element 1 to 5 designed so that there is a groove or recess on the lateral edge surface 12 contains. An adjacent (not shown) Wärmdämmelement has at the lateral edge surface, for example a Spring or one to the recess 12 formed complementary recess so that two adjacent heat-insulating elements can be connected at the lateral abutment surface via the coupling of the example, tongue / groove.

In 5 shows the area 5 ' Cuts in the thermal insulation element 1 for better representation of the internal structure. In this area is the enveloping layer 10 not shown.

Basically it is for a function of the thermal insulation elements 1 less important from the above embodiments, whether the cells have the same lengths or different lengths. The diameter of the cells may be the same for all cells or vary.

A preferred embodiment comprises cells in the form of a honeycomb structure with a diameter of 1-10mm and a wall thickness of 5-150μm. The cells have a length of 1-50 cm in this embodiment. The thermal insulation element preferably consists of 3-1000 layers of these cells and is designed to cover an area of 100 × 100 mm ² to 1000 × 1000 mm ² . To the heat conduction of a heat-insulating element 1 along the edges to reduce, the edge region may be formed in the form of a groove or a step, so that profiles of adjacent thermal insulation elements interlock or overlap. In order to ensure a permanent vacuum enclosure, it is preferable to use glass or an air-impermeable plastic as the material. The quality of the vacuum is preferably to be chosen so that the free path of the remaining gas molecules is a multiple of the diameter of the elements, for example, in a fine or high vacuum at a pressure of 10 to 10 ^-4 Pa.

A preferred embodiment is a thermal insulation element based on 1 , The thermal barrier element according to the invention consists essentially of a glass structure. Glass as a material combines the advantages of high diffusion-tightness and pressure stability with low raw material costs. This glass structure consists of eight layers each with a honeycomb diameter of 5 mm, a length of each honeycomb element of 50 mm and a wall thickness of 0.050 mm embedded in a polystyrene shell of 5 mm thickness. The entire element has a width of 750 × 750mm ² and a thickness of 50mm. The residual pressure of the trapped gas (air) is less than 1 Pa (to withstand this pressure against the external pressure would require at least a wall thickness of 8.5 microns). Between each of the eight layers is an infrared-reflective aluminum layer. The thus formed thermal insulation element has a thermal conductivity of λ ≈0.01 W / mK. By comparison, this value is at least a factor 4 smaller than the best classical insulating materials (eg mineral wool λ ≈0.04 W / mK). This means, for example, that an extremely well-insulated house wall of a passive house can not be realized with an insulation thickness of 350mm, but with an insulating layer of 100mm. This allows for the same insulating effect significantly slimmer wall structures. In passive house construction, the classically insulated walls are sometimes provided with insulating material with a layer thickness of 350mm. This typically leads to a total wall construction with a wall thickness of 500mm and more for solid houses in the passive house standard. This aesthetic disadvantage is avoided with the device according to the invention. An essential second advantage, which plays a major role in the urban housing sector in particular, is land use. With the same external size of the house is significantly more living space available through the use of the device according to the invention (per meter wall surface and floor results in a surface difference of 0.25m ² ). In a two-story single-family house with a floor space of ten by ten meters, this corresponds to an area gain of 18m ² (20m ² minus 10% wall portion). The total cost of a home is typically quoted in Euros per square meter of living space. The area profit would correspond with a total price of 1200 € / m ² a sum of 21600 €. Even if this is only a very simplified estimate, it nevertheless quickly becomes apparent that possible additional costs of such a system can be relativized or even overcompensated for today compared to insulating materials commonly used today and according to the state of the art.

In order to improve the processability of the thermal insulation element, the thermal insulation element may be surrounded by an outer shell. This shell is preferably made of relatively soft material with thermal insulation properties. This may, for example, be a wrapper with liquid wood or polystyrene.

To reduce radiation heat losses, in some embodiments within the cells, between the individual cells and / or between the layers, an infrared-reflective coatings are applied. The coating is realized in one embodiment by vapor deposition of a metal layer, for example a thin aluminum layer. Even small infrared-reflecting particles between the cells or as part of the material of the cells can take over the function of infrared reflection. The infrared-reflective coating not only reflects heat radiation from a warmer area outside the thermal barrier element, it also reduces one Heat radiation from the thermal insulation element to an environment.

In a further embodiment, the thermal insulation element is made transparent and acts in conjunction with a light-absorbing layer on the inside of the building as a transparent thermal insulation.

In a further embodiment, photovoltaic elements are integrated on or in the thermal insulation element. This makes it possible to produce cost-effective and functionally optimized facade and roof elements with integrated photovoltaic technology or with solar collectors. This can go so far that the thermal insulation element takes on both a structural-like function as masonry, as well as the thermal insulation function for the thermal building shell takes over and serves as a housing and weatherproof encapsulation of photovoltaic elements.

Another embodiment is a thermal insulation element which is composed of individual closed honeycomb, cuboid or round cells. These cells are evacuated or filled with a gas with low residual pressure. The closed cells are also filled with a filling material (e.g., foams, perlites, natural or synthetic fibers). An advantage of the invention that only individual cells are affected by damage of the element and the overall functionality of the heat-insulating element is maintained, is also given in this embodiment.

Another embodiment may include getters that bind possible residual gases and moisture present in the individual cells.

In the following, an embodiment of a manufacturing process of a heat-insulating element will be described.

A raw material, such as glass or plastic, is melted and passed by means of a supply line in an evacuated manufacturing chamber (vacuum chamber). In one embodiment, in the manufacturing chamber, the raw material is pressed through a mold in a continuous process. This shape forms, for example, a series of tubes or a honeycomb structure two-dimensionally, so that strands emerge from this shape, which have a corresponding cross-section. The manufacturing chamber is completely evacuated or may still have a residual pressure of special gases or air. The molded material is mechanically guided after leaving the mold so that the desired shape is formed. In one embodiment, the structure is thereby stretched to achieve very thin uniform wall thicknesses. The strands are tapered in the following step at regular intervals by means of mechanical devices, for example by impellers, so that they are closed at intervals by constrictions. This closure leads to the formation of local three-dimensional chambers, ie the cells in which the production chamber pressure is enclosed and thus preserved. The order of the process steps can also be designed differently: first constrict, then stretch, or first stretch and then constrict. The structure cools down in the further course and hardens.

The thus pressed and drawn structure of several strands with cells in a plane represents a layer of insulating material.

To produce a multi-layer thermal insulation element, the o.g. Manufacturing arrangement spatially arranged several times in a row in one embodiment. The individual layers are laid one on top of the other in the course of the process and connect to the thermal insulation element. In another embodiment, only one layer is formed and superimposed in meanders. In an alternative embodiment, at least one layer is rolled up into a tube.

Depending on the temperature and the resulting strength, the contact surfaces between the strands are larger or smaller. For example, if the strands are already nearly cured when stacked, they barely change shape, leaving the contact areas small. If the strands are not so far hardened, the contact surfaces become larger due to adhesion forces and it can form in a particular embodiment strands with hexagonal cross-sections.

Before the strands are assembled in multiple layers, they are at least cooled to the extent that the cavities are preserved inside the cells despite a load by adjacent strands. In one embodiment, the strands are joined together before they are fully cured so that they bond to adjacent strands so that no fluid penetrates between the strands.

In one embodiment, spaces become 7 sealed between strands and / or free areas around constrictions in some places before two layers are stacked on top of each other so that the interstices 7 and / or free areas around the constrictions remain evacuated when the thermal insulation element is removed from the manufacturing chamber.

In some embodiments, individual layers are provided with an infrared light and heat radiation reflecting layer. This can be realized in the form of a vapor deposition with metallic layers by a sputtering process or by applying thin films.

In one embodiment, a cutting device cuts off the heat-insulating elements in the desired length. The heat insulation elements are then removed after sufficient cooling and thus fixing the mold out of the production chamber via a vacuum lock.

Thus, a thermal insulation element with very low thermal conductivity is obtained.

For further processing, the process chain mentioned above can optionally be followed by a further process chain in which the finished modules are introduced into a mold. The mold is filled with a low cost thermal insulating material (e.g., styrofoam, plastics, natural or liquid wood). Through this process step, the inner structure is surrounded by a protective cover. The material properties of the protective cover can be chosen so that they can be used directly as a carrier material for the intended use, e.g. suitable for plasters. The protective cover is equipped in some embodiments with tongue and groove or similar structures that can bring elements almost free of heat bridges together. In addition, the protective cover facilitates the processing and prevents functional damage to the insulating element, as in particular in the construction industry often harsh environmental conditions are to be found.

Other variants and embodiments of the present invention will become apparent to those skilled in the art within the scope of the following claims.

Claims (28)

Thermal thermal insulation element, comprising at least two layers (2, 2A, 2B, 2C, 2E, 2F), wherein: - the layers (2, 2A, 2B, 2C, 2E, 2F) each consist of a plurality of strands (3, 3A, 3B, 3C, 3D), which are arranged approximately parallel to one another and connected to each other in a plane, characterized in that - the strands (3, 3A, 3B, 3C, 3D) each of a plurality of hollow, at least partially evacuated elongated cells (4A, 4B, 4C) arranged in a row one behind the other and separated from each other by constrictions (5A, 5B), and the cells (4A, 4B, 4C) of a layer (2, 2A, 2B, 2C, 2E, 2F) to the respective adjacent cells (4A, 4B, 4C) of an adjacent layer (2, 2A, 2B, 2C, 2E, 2F) are arranged offset in layer plane, - wherein the cells (4A, 4B, 4C ) were made of glass and assembled during curing in such a way that each cell (4A, 4B, 4C) with the cells of the adjacent strands (3A, 3B, 3C, 3D) of the same layer and the cells of the adjacent layers (2A, 2B, 2C, 2D) is directly connected. After heat insulation element Claim 1 in which the cells (4A, 4B, 4C) are approximately tubular. Thermal insulation element according to one of Claims 1 or 2 in which a cross section of the at least two superimposed layers (2, 2A, 2B, 2C, 2E, 2F) has a pattern of regular hexagons. The thermal barrier element of any one of the preceding claims, further comprising an infrared reflective coating. After heat insulation element Claim 4 in which the infrared-reflective coating is disposed between the layers (2, 2A, 2B, 2C, 2E, 2F). Thermal insulation element according to one of the preceding claims, which is transparent to light in the visible range. Heat-insulating element according to one of the preceding claims, which is transparent to light in the visible range and which is provided on the back with a light-absorbing layer or a photovoltaic layer. A thermal barrier element according to any one of the preceding claims which is coated on a surface with a photovoltaic layer. A thermal insulation element according to any one of the preceding claims, further comprising a cover (8A, 8B) for protection against mechanical stress. Thermal insulation element according to one of the preceding claims, which is designed to enter into a connection with a facade coating. Thermal insulation element according to one of the preceding claims, which has at least four layers (2, 2A, 2B, 2C, 2E, 2F). After heat insulation element Claim 11 in which in each case at least two adjacent layers (2, 2A, 2B, 2C, 2E, 2F) are each combined in a layer package (20A, 20B, 20C) in which the constrictions of the layers (2, 2A, 2B, 2C, 2E, 2F) are in the same Are arranged with adjacent constrictions of different layers (2, 2A, 2B, 2C, 2D, 2E, 2F) in each constriction plane (50A, 50B, 50C) perpendicular to the strand direction, and the constriction planes (50A, 50B, 50C ) of adjacent layer packages (20A, 20B, 20C) are offset from each other. A thermal barrier element according to any one of the preceding claims, wherein gaps (7) between the cells (4A, 4B, 4C) are evacuated. A thermal insulation element according to any one of the preceding claims, wherein an insulating effect depends on a direction of a temperature gradient. Thermal insulation element according to one of the preceding claims, which has at lateral edges a connection profile for the positive connection with an adjacent thermal insulation element. Thermal insulation element according to one of Claims 1 to 14 , which has a coating on the side edges for thermally insulating connection with an adjacent heat-insulating element. Thermal insulation element according to one of the preceding claims, which is combined with a photovoltaic element or a solar collector. A method for producing a thermal insulation element, comprising: - melting raw material for the thermal insulation element, - injecting the molten material through an opening in an evacuated chamber as at least one strand (3, 3A, 3B, 3C, 3D), enclosing one or more cavities, - multiple entangling of the or each strand (3, 3A, 3B, 3C, 3D) at intervals along the strand (3, 3A, 3B, 3C, 3D), and - stretching the or each strand (3, 3A, 3B, 3C , 3D), such that the wall thickness of the strand (3, 3A, 3B, 3C, 3D) is reduced to the desired degree, characterized in that a plurality of strands (3, 3A, 3B, 3C, 3D) of a Layer (2, 2A, 2B, 2C, 2E, 2F) is formed, in which the strands (3, 3A, 3B, 3C, 3D) are arranged approximately parallel to each other and connected in a plane and in which each strand (3 3A, 3B, 3C, 3D) abuts two further strands (3, 3A, 3B, 3C, 3D), the material being glass and the strands (3, 3A, 3B, 3C, 3D) before they are cured. Method according to Claim 18 in which the layer (2, 2A, 2B, 2C, 2E, 2F) is provided with an infrared-reflective coating. Method according to one of Claims 18 or 19 in which the layer (2, 2A, 2B, 2C, 2E, 2F) is adapted to the shape of a body to be insulated. Method according to Claim 19 in which the layer (2, 2A, 2B, 2C, 2E, 2F) is rolled up into a tubular thermal insulation element. Method according to one of Claims 18 to 21 in which at least two layers (2, 2A, 2B, 2C, 2E, 2F) are stacked. Method according to Claim 22 in which the constrictions of the strands (3, 3A, 3B, 3C, 3D) of one of the at least two layers (2, 2A, 2B, 2C, 2E, 2F) to the constrictions in a further layer (2, 2A, 2B, 2C, 2E, 2F) are offset in the direction of the strand. Method according to Claim 22 in which in each case at least two layers (2, 2A, 2B, 2C, 2E, 2F) are arranged in layer packages, wherein adjacent constrictions of different layers (2, 2A, 2B, 2C, 2E, 2F) are arranged in each layer package in a constriction plane and the constricting planes of adjacent layer packages are offset from each other. Method according to one of Claims 22 to 24 in which the at least two layers (2, 2A, 2B, 2C, 2E, 2F) are divided into uniform sections. Method according to Claim 25 in which the at least two layers (2, 2A, 2B, 2C, 2E, 2F) are divided into uniform sections in such a way that they have a connection profile to a positive connection at lateral edges. Method according to one of Claims 22 to 26 in which the at least two layers (2, 2A, 2B, 2C, 2E, 2F) form a thermal insulation element. Method according to one of Claims 21 or 27 in which the thermal insulation element is removed through a vacuum lock from the evacuated chamber.

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