EP2507463A1

EP2507463A1 - Heat-insulating arrangement and method for heat insulation

Info

Publication number: EP2507463A1
Application number: EP10784992A
Authority: EP
Inventors: Herbert Sinnesbichler; Michael Eberl
Original assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Current assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Priority date: 2009-12-01
Filing date: 2010-11-27
Publication date: 2012-10-10
Anticipated expiration: 2030-11-27
Also published as: WO2011066929A1; PL2507463T3; DE102009056329A1; EP2507463B1

Abstract

The invention relates to a heat-insulating arrangement for a building window, containing a first sheet-like element and a second sheet-like element, which are spaced apart from one another, wherein at least one sheet-like element is of at least partially reflecting design in the infrared spectrum range, wherein the first sheet-like element and the second sheet-like element are arranged on the outside of the building window and the first sheet-like element is arranged with a first fastening device in front of the building window and the second sheet-like element is arranged with a second fastening device in front of the building window, it being possible for the first sheet-like element and the second sheet-like element to be operated independently of one another thereby. The invention also relates to a method for the heat insulation of a building window, in the case of which a first sheet-like element and a second sheet-like element are spaced apart from one another on the outside of the building window, wherein at least the second sheet-like element is of at least partially transparent design in the visible spectrum range and of at least partially reflecting design in the infrared spectrum range, and the second sheet-like element is arranged in a permanent or movable manner in front of the building window by means of a second fastening device and the first sheet-like element is arranged in a movable manner in front of the building window by means of a first fastening device.

Description

Patent Application:

Thermal protection device and method for thermal insulation

applicant:

The invention relates to a heat protection device for a building window, comprising a first surface element and a second surface element, which are arranged at a distance from one another, wherein at least one surface element in the infrared

Spectral region is formed at least partially reflective.

EP 0 074 952 B1 discloses a heat-insulating blind of the type mentioned in the introduction. This known blind consists of two thin and transparent

Layers of material. By means of a spacer, both layers of material can be lowered at a predeterminable distance on the inner side of the window facing the room. In this way, the loss of heat energy through the window should be reduced without restricting the view through the window. A disadvantage of this prior art, however, that the material layers of only 75 μητι have a low mechanical stability. Furthermore, the heat protection device affects the visual impression of the room.

The invention is therefore based on the object to reduce heat loss through glass facades or window openings, without having to accept the disadvantages mentioned.

The object is achieved by a thermal protection device for a building window, comprising a first surface element and a second surface element, which are spaced from each other, wherein at least one surface element in the infrared spectral region is at least partially reflective, wherein the first surface element and the second surface element on the Outside of the building window are arranged and the first surface element with a first

Fastening device is arranged in front of the building window and the second surface element with a second fastening device in front of the building window is arranged, by means of which the first surface element and the second surface element are independently operable.

Furthermore, the solution of the object in a method for thermal insulation of a building window, in which a first surface element and a second surface element spaced from each other on the outside of the building window are arranged, wherein at least the second surface element in the visible spectral region at least partially transparent and in the infrared spectral region at least partially is reflective and the second surface element by means of a second

Fastening device is arranged permanently or movably in front of the building window and the first surface element is arranged by means of a first fastening device movable in front of the building window.

The heat protection device according to the invention is suitable for building windows, which can be opened by means of appropriate fittings or for fixed glazing. A building window according to the present invention is therefore an at least partially transparent component, such as a facade element, a window or a roof window.

On the outside of the building, a first and a second surface element is arranged at least in front of the building window. Both surface elements have a predeterminable distance from each other. At least one surface element is at least partially reflective, at least in the infrared spectral range. In this way, two insulating layers of air are formed between the outside of the building window, the second surface element and the first surface element. Due to the additional static layers of air between the outside of the building window and the surrounding atmosphere, the heat loss through convection is effectively reduced. Due to the infrared reflecting properties of at least one

Surface element also emanating from the building window radiant heat can be reflected back into the interior. In this way, the heat loss is effectively reduced.

According to the invention, the surface elements can either be arranged permanently in front of the window and reduce the heat loss 24 hours a day. In other

Embodiments of the invention, the surface elements may be movable, so that These do not obstruct the view, the ventilation or the exit from the window. According to the invention, the surface elements can be operated independently of one another so that either one or both or none of the surface elements is arranged in front of the window opening. In some embodiments of the invention, a surface element or both

Surface elements in the visible spectral range to be at least partially transparent. In this way, the surface element can be arranged permanently in front of the building window. Due to the transparency of the surface element in the visible spectral range, the view from the building is impaired only slightly by the building window equipped according to the invention.

In some embodiments of the invention, a surface element with partial transparency is formed from a material which, in the spectral range between 780 nm and 380 nm wavelength at at least one wavelength or in at least one wavelength range, absorbs less than 50% or less than 30% or less than 10% of the irradiated intensity. In some embodiments of the invention, a surface element with partial transparency is formed from a material which is in the spectral range between 780 nm and 380 nm wavelength at at least one wavelength or wavelength in at least one wavelength range has a transmission of less than 30% or less than 20% or less than 10% of the radiated intensity and has recesses or holes which have an area fraction of more than 10% or more than 20% or more than 40 % of the total area of the area element, in this case the term "partial" refers to the location area. In some embodiments of the invention, at least one surface element may be made opaque. As an added benefit, the surface element can then be used to darken the room and during that effectively reduce the heat loss through the building window, especially during the night hours. On the other hand, such a surface element already exists on the building

Include darkening, so that an existing building retrofitted in a particularly simple manner with the heat protection device according to the invention can be, by only a second surface element fixed or movable mounted in front of the window.

If the first surface element of the heat protection device is made opaque and the second surface element is at least partially optically transparent or at least translucent, the second surface element can remain permanently arranged in front of the building window, whereas the first surface element is designed to be movable. Such a movable attachment of the surface element can be realized by means of a fastening device, by means of which the surface element is rollable, hinged or displaceable. As a result, a partial effect of the heat protection device is achieved permanently and the full effect of the heat protection device during the darkening of the room, for example, at night, although the heat losses through the building windows are maximum.

If the second surface element has an infrared-reflecting coating on the side facing the building window, heat radiation emerging from the building through the building window is reflected back into the building by the second surface element. If the second surface element has an infrared-reflecting coating on both sides or consists of an infrared-reflecting material, the second surface element can be arranged all year in front of the building window and in the same way reduce excessive heating of the building interior in intense sunlight. In this way, the second surface element can have a positive effect on the indoor climate and the whole year all year round

Exercise energy use of the building. During the winter months and / or during the night, when due to a reduced outdoor temperature, increased heat loss through the building window occurs, the heat loss through the building window can be further reduced by means of the second surface element.

In some embodiments of the invention, the first surface element and the second surface element may be arranged with a common fastening device in front of the building window, by means of which the first surface element and the second surface element is jointly movable. This allows a simple temporary

Removal of the entire thermal insulation, for example, to ventilate the room behind the window or the exit of one with a French window to allow equipped room. The fastening device may be configured to roll, displace or pivot the surface elements.

The invention will be explained in more detail with reference to an embodiment without limitation of the general inventive concept. 1 shows a cross section through a building window with the heat protection device according to the invention.

In the cross section according to FIG. 1, parts of a building wall 1 can be seen. The building wall 1 defines a room of a building, for example a residential or office building. The interior extends on the right side of the building wall. 1 The exterior of the building extends in Figure 1 on the left side of the building wall. 1 The building wall 1 has an opening. The opening is closed by means of a building window 3, in order to avoid drafts and to ensure a comfortable climate in the interior of the building.

The building window 3 has a glazing, which in some embodiments of the invention in the interior of persons located the view from the building window 3 allows. In other embodiments of the invention, the glazing 10 of the building window 3 as tinting a tint and / or a

Have mirroring, which prevents the view from the room or the view of the room in whole or in part or at least difficult. The glazing 10 may be an insulating glazing containing a plurality of individual slices. Between a plurality of disks, a gap may be formed which is filled with an insulating gas of predeterminable composition and specifiable pressure. In other embodiments, the

The space between the panes can be evacuated in order to further reduce the heat transmission through the glazing 10 in this way. Each individual pane of the glazing 10 may have a coating which increases the scratch resistance of the pane and / or reflects incident heat radiation. The reflection of heat radiation can on the one hand be provided to reduce the heat loss from the interior of the building in the cold season. In other embodiments, the

Coating can be used to prevent in the warm season the excessive entry of solar heat radiation into the room. The glazing 10 of the building window 3 is fixed in the wall opening by means of a frame 2. The frame 2 can be made in two parts, so that the glazing can be opened by means of a tilting and / or rotating and / or sliding mechanism. In other embodiments of the invention, the frame 2 may be in one piece, so that the glazing 10 of the building window 3 is designed as fixed glazing.

On the side facing away from the room of the building window 3 and thus on the outside of the building, the heat protection device 9 according to the invention is arranged. The thermal protection device 9 includes a first surface element 5 and a second surface element 4, which are arranged at a distance from each other. In some embodiments, the distance 12 between the building window 3 and the second surface element 4 may correspond approximately to the distance 11 between the second surface element 4 and the first surface element 5. In this way, the best possible thermal insulation and the lowest possible heat loss is achieved by the proposed heat protection device 9. In both spaces 1 1 and 12 formed in this way ever an insulating air cushion, which prevents the direct action of atmospheric air movements on the glazing 10 of the building window 3 and the associated discharge of heat energy.

In addition to the heat loss by convection can be effectively prevented by the proposed heat protection device 9, the heat loss by radiation. For this purpose, it can be provided in some embodiments of the invention that at least one of the surface elements 4 and / or 5 is at least partially reflective in the infrared spectral range. Such a reflection property can be achieved, for example, by a coating. Such a coating may contain or consist of gold, aluminum or titanium oxide. The coating can be applied on one or both sides. In some embodiments, the coating is applied at least on one side to the second surface element 4 on the side facing the building window 3. In another embodiment of the invention, the second surface element 4 can have an infrared-reflecting coating on both sides or consist entirely of an infrared-reflecting material. In this way, the second surface element reduces both the heat loss from the room as well as the penetration of unwanted solar heat in the room. A special High thermal insulation results when the second surface element 4 is provided on both sides at least partially with an infrared-reflective coating.

In some embodiments, the infrared-reflecting coating may be designed to produce a reflectivity of more than 50%, at least in the spectral range between about 40 μm and about 0.8 μm wavelength, at least in a sub-range. In a further development of the invention, the reflectivity can be more than 80%. In some embodiments of the invention, a reflectivity of more than 60% in the spectral range between 30 μητι and 3 pm wavelength can be achieved.

In some embodiments of the invention, the second surface element 4 may be transparent at least in the visible spectral range between about 780 nm and about 380 nm wavelength. In another embodiment of the invention, the transparency range extends at least between about 550 nm and about 380 nm wavelength. In yet another embodiment of the invention, the transparency range extends at least between about 780 nm and about 550 nm

Wavelength. Transparency in the sense of the present invention is understood in some embodiments of the invention to mean a permeability of more than 25%, in some embodiments more than 60%, in yet another embodiment more than 80% of the incident radiation. In this way, the view from the room through the second surface element 4 is not obstructed. Thus, the second surface element 4 may be almost invisible to the occupant of the building.

In some embodiments of the invention, the first surface element 5 may also be transparent, as described above for the second surface element 4. In this case, both surface elements can remain permanently installed in front of the building window 3 and in this way permanently reduce the heat loss of the building through the building window 3.

In other embodiments of the invention, the first surface element 5 may be opaque in the visible spectral range. In this way, the first surface element 5 can be used in a manner known per se for darkening the space behind the building window 3. Thus stands during the

Daytime alone, the second surface element 4 and the enclosed by this Air space 12 for the insulation of the building window 3 available. As a result, the heat loss of a known building window 3 can be reduced throughout the day. During the night, when the outside temperature falls particularly low and the heat loss through the building window 3 is particularly large, by additional darkening of the room through the second surface element 5, a further air space 1 1 are created.

In some embodiments, a further infrared-reflecting layer may be brought in front of the building window 3 by the first surface element 5. As a result, the insulation of the building window 3 is further increased during the particularly cold night hours. In order to be able to operate the first area element and the second area element independently of one another, it may be provided in some embodiments that the first area element 5 is arranged with a first attachment device 7 in front of the building window 3 and the second area element 4 with a second attachment device 8 in front of the building window 3 is arranged. For example, it can comprise a frame, which can be permanently or detachably connected to the frame 2 of the building window 3. In this way, the second surface element 4 can be mounted seasonally or permanently in the window recess in front of the building window 3. In some embodiments of the invention, the second fastening device 8 can also be designed to arrange the second surface element 4 movably in front of the building window 3, for example rollable or displaceable. As a result, the second surface element 4 can be removed for ventilation, for cleaning or for exit from the building window 3. In some

Embodiments of the invention, the second surface element 4 with the

Fixing device 8 for energetic building renovation in the inventory subsequently be attached to the frame 2 of the building window 3.

The first fastening device 7 can likewise allow a static fastening of the first surface element 5. In some embodiments of the invention,

However, especially when the first surface element 5 is configured opaque, the first fastening device 7 allows a movable mounting of the first surface element 5. In the embodiment shown in Figure 1, the first surface element 5 on a arranged in the first fastening device 7 shaft 6 is rollable. The shaft 6 can in a conventional manner by a hand crank, a winding belt or a Electric motor can be rotated, whereby the first surface element 5 can be wound up or unwound. Thus, the proposed thermal protection device 9 is particularly suitable for the energetic renovation of old buildings, if as the first surface element 5 and as a first fastening device 7 an already existing on the building roller shutter is used. In some cases, the material of the shutter during the installation of the heat protection device 9 can be provided on the inside with an additional infrared-reflective coating or replaced by an infrared-reflective material.

The effectiveness of the proposed thermal protection device will be illustrated below with reference to a comparative example. It was an interior of a

Building heated to a constant temperature of about 21 ° C. In the room was a building window 3, which was equipped with a double glazing known per se. In a first experiment, the building window 3 was used without the proposed heat protection device 9, ie without the first Flächenele- element 5 and the second surface element 4. At an outside air temperature of B ° C, a heat flux of 16.3 W / m ^{2 was} determined. This results in a heat transfer coefficient of 1, 02 W / m ² K.

In the next experiment, a well-known shutter was closed on the outside of the building window 3. In this case, a heat flux of 14.4 W / m ^{2 was} determined at an outside air temperature of 3.2 ° C. This results in a heat transfer coefficient of 0.81 W / m ² K.

Finally, an experiment was carried out with the heat protection device 9 proposed according to the invention. The heat protection device 9 comprised a second surface element 4, which consisted of a double-sided infrared-reflecting film. The first surface element 5 consisted of a commercial roller shutter with

Plastic blades. At an outside temperature of -1.5 ° C, the heat flow was reduced to 10, 1 W / m ² . Thus, the heat transfer coefficient of the building window 3 by the heat protection device 9 according to the invention improves to 0.45 W / m ² K. Thus, the heat loss through the building windows 3 can be approximately halved by the heat protection device proposed according to the invention. Of course, the invention is not limited to the embodiments shown in the figure and the embodiments. The above description is therefore not to be considered as limiting, but as illustrative. The following claims are to be understood so that a named feature is present in at least one embodiment of the invention. This does not exclude the presence of further features. If the claims and the above description define "first" and "second" features, then this term serves to distinguish two similar features without prioritizing them.

Claims

claims

Heat protection device (9) for a building window (3), comprising a first surface element (5) and a second surface element (4), which are spaced from each other, wherein at least one surface element (4, 5) is formed in the infrared spectral region at least partially reflective and the first surface element (5) and the second surface element (4) on the

Outside of the building window (3) are arranged, characterized in that the first surface element (5) with a first fastening device (7) in front of the building window (3) is arranged and the second surface element (4) with a second fastening device (8) in front of the Building window (3) is arranged, by means of which the first surface element (5) and the second surface element (4) are operable independently of each other.

Apparatus according to claim 1, characterized in that the first surface element (5) by means of the first fastening device (7) is movable.

Device according to one of claims 1 or 2, characterized in that the second fastening device (8) comprises a frame.

Device according to one of claims 1 to 3, characterized in that the second surface element (4) by means of the second fastening device (8) is movable.

Device according to one of claims 1 to 4, characterized in that the first surface element (5) and the second surface element (4) and the building window (3) are arranged approximately parallel to each other and the distance (12) between the building window (3). and the second surface element (4) corresponds approximately to the distance (1 1) between the second surface element (4) and the first surface element (5).

Device according to one of claims 1 to 5, characterized in that the second surface element (4) on the building window (3) facing side and / or on the building window (3) facing away from an infrared reflective coating.

7. Device according to one of claims 1 to 5, characterized in that the second surface element (4) has on both sides an infrared-reflective coating or contains or consists of an infrared-reflective material.

8. Device according to one of claims 1 to 7, characterized in that the second surface element (4) is at least partially transparent, at least in the spectral range between 780 nm and 380 nm wavelength

9. Device according to one of claims 1 to 8, characterized in that the first surface element (5) is at least partially opaque at least in the spectral range between 2500 nm and 280 nm wavelength. 10. Device according to one of claims 1 to 9, characterized in that the second surface element (4) at least in the infrared spectral range between 50 pm and 0.8 pm wavelength has a reflectivity of more than 60%, in particular more than 80%.

1 1. Process for the thermal insulation of a building window (3), in which a

first surface element (5) and a second surface element (4) spaced apart on the outside of the building window (3) are arranged, wherein at least the second surface element (4) in the visible spectral region is at least partially transparent and at least partially reflective in the infrared spectral region and the second surface element (4) by means of a second fastening device (8) permanently or movably in front of the building window (3) is arranged and the first surface element (5) by means of a first fastening device (7) movable in front of the building window (3) is arranged.

12. The method of claim 1 1, characterized in that electromagnetic radiation having a wavelength between 780 nm and 380 nm, the second

Surface element (4) at least partially penetrates

13. The method of claim 1 1 or 12, characterized in that

electromagnetic radiation having a wavelength between 2500 nm and 280 nm is at least partially absorbed by the first surface element (5).