EP0069837A2 - Self-supporting insulating element - Google Patents

Abstract

A single foil is biaxially stretched on a frame for movement relative thereto by being secured intermittently to a single rubbing strip over a guide ledge. The rubbing strip is stretchable and movable lengthwise of the associated frame side. Torsional forces arising because of the one-sided loading of the frame by the stretched foil are taken up by the frame which is made with a torsionally rigid cross-section. The single foil can be clamped without creasing and in a manner which ensures freedom from creasing notwithstanding differences in the heat expansion of the foil and frame.

Description

The invention relates to a self-supporting insulation element for insertion between the panes of a double or composite window, consisting of a single coated film which is biaxially stretched longitudinally and stretched over a clamping frame, the sides of which are bent in the untensioned state according to a curve curved on one side.

From DE-OS 28 50 749 an insulation element, preferably for windows with a rectangular or square surface in the usual way, is known, in which foils connected in pairs are stretched out in the manner described above via a tenter frame, the sides of which are untensioned relative to the straight one The connecting seam of the two foils runs along a curve that is continuously curved on one side, preferably along the bending line of a uniformly loaded, non-clamped beam.

• - Es muss sichergestellt sein, dass die Spannkräfte nicht zu gross und nicht zu klein werden. Zu grosse Spannkräfte verursachen bei beschichteten Folien Beschädigungen der Beschichtung, wodurch Ansatzstellen für einen erhöhten Korrosionsangriff geschaffen werden; zu kleine oder unregelmässige Spannkräfte führen zu Faltenbildungen. Bei Raumtemperatur, d.h. etwa 20⁰ C, sollen die Spannkräfte beispielsweise etwa 1 N/cm Länge betragen; die Sicherstellung geeigneter Spannkräfte soll sich dabei auf einen Temperaturbereich von -20° bis +50⁰ C erstrecken.
• - Das Isolationselement soll freitragend ausgebildet sein, damit die Reaktionskräfte der Folienspannung bei Verbundfenstern nicht durch den luft- und wasserdampfdichten und daher sehr empfindlichen Randverbund aufgenommen werden müssen; ein selbsttragendes Isolationselement ist darüberhinaus in einfacher Weise in bestehende Doppelfenster einsetzbar.

Since on the one hand each additional film leads to loss of absorption and reflection in the visible spectral range and reduces the optical sharpness and clarity of the view, and on the other hand with coated films available today a single stretched film is already very good and the heat transfer is sufficiently inhibited to achieve insulation values the endeavor to provide the insulation elements discussed above with only a single, biaxially stretched film. Accordingly, the invention has for its object to provide a way to biaxially stretch a single film in the desired manner, ie in relation to the frame due to different thermal expansions in the longitudinal direction. The solution to this task must also satisfy the following boundary conditions, which have already been taken into account in the insulation element according to DE-OS 28 50 749:

• - It must be ensured that the clamping forces do not become too large and not too small. Excessive clamping forces cause damage to the coating on coated foils, creating points of contact for increased corrosion attack; too small or irregular tension forces lead to wrinkles. At room temperature, ie about 20 ^° C., the clamping forces should be, for example, about 1 N / cm in length; ensuring suitable clamping forces should extend to a temperature range of -20 ° to +50 ⁰ C.
• - The insulation element should be self-supporting, so that the reaction forces of the film tension in composite windows do not have to be absorbed by the air and water vapor-tight and therefore very sensitive edge bond; a self-supporting insulation element can also be used in a simple manner in existing double windows.

This object is achieved according to the invention in that the frame consists of a torsionally stiff profile which carries a guide strip on one side, through which at least one slide band, which is stretchable in its longitudinal direction, is slidably held and guided along each frame side, and that the film is also connected to the slide tape via separate adhesive points such that the adhesive points are offset from the frame relative to the plane of the stretched film.

In this way, the film is firmly connected only to the sliding band; Different thermal expansions of the film and frame are therefore possible. The required one-sided arrangement of the film causes asymmetrical force effects on the frame; this is therefore subject to torsional stress. Due to its torsional rigidity, this load is counteracted and a disruptive twisting of the profile is prevented. The longitudinal extensibility of the slide tape, which can also be ensured by its separation into individual sections, in conjunction with the separate adhesive points ensures that when the curved frame is tensioned, the tensioning forces acting on the film are evened out over the entire length of one side of the frame. Due to the separate points of adhesion, local defects occur on the film, which cause small "micro" distortions and wrinkles; their influence on the stretched film in the visible area is avoided by moving the adhesion points from the plane of the stretched film, which causes the film to be stretched over a protruding continuous edge.

Ensuring the "right", i.e. Clamping forces that are not too large and not too small are carried out with the help of the curvature of the unstressed frame sides determined by calculation or experiment relative to the "straight" frame in the tensioned state. The self-supporting property of the element is guaranteed by the strength of the self-contained, stretched frame.

The torsional stiffness of the frame can advantageously be achieved by a hollow profile closed in the circumferential direction; metals used as frame material are primarily used in window construction. However, it is also possible to use fiber-reinforced plastic frames with additional metal inserts if necessary.

In order to avoid or at least make it difficult to flow around in a composite or double window when the insulation element is inserted on the outside between the frame and the window boundary, it is expedient if the film overlaps the tensioned frame beyond the point of adhesion to the outside. A simple possibility for tensioning the frame is obtained if the frame sides are tensioned vertically displaceably at their corners via corner pieces fitted into their hollow profile. This construction detail also has the advantage that the described torsional load on the frame can be absorbed in a simple manner at its corners. Finally, it is also advantageous if the displacement takes place at least approximately through the last point of adhesion of the sliding band on one side and at least approximately in the longitudinal axis of the points of adhesion on the side perpendicular thereto, since this also means that the direction of action of the clamping forces at the corners is essentially perpendicular or parallel runs to the points of adhesion of the foils and the sliding tape, thus reducing the possibility of wrinkles.

The connection of the film to the slide belt, which is preferably made of plastic, is expediently carried out in the case of prestressed frames in which the slide belt is already inserted, by welding or gluing.

• Fig. 1 zeigt in einem Ausschnitt eine Aufsicht - von rechts in Fig. 2 - auf die Fläche eines Verbundfensters, das mit dem erfindungsgemässen Isolationselement ausgestattet ist;
• Fig. 2 ist ein Schnitt II-II von Fig. 1;
• Fig. 3 gibt als Detail aus Fig. 2 vergrössert das Rahmenprofil und die daran befestigte Folie wieder;
• Fig. 4 ist ein Schnitt IV-IV von Fig. 3 durch eine Ecke des Rahmenprofils;
• Fig. 5 zeigt in gleicher Darstellung wie Fig. 3 ein zweites Ausführungsbeispiel eines Rahmenprofils, während
• Fig. 6 eine zweite Ausführungsform des Gleitbandes wiedergibt.

In the following the invention based on execution examples explained in more detail.

• FIG. 1 shows a detail of a top view - from the right in FIG. 2 - of the area of a composite window which is equipped with the insulation element according to the invention;
• Fig. 2 is a section II-II of Fig. 1;
• FIG. 3 shows, as a detail from FIG. 2, an enlarged view of the frame profile and the film attached to it;
• Fig. 4 is a section IV-IV of Fig. 3 through a corner of the frame profile;
• Fig. 5 shows in the same representation as Fig. 3, a second embodiment of a frame profile, while
• Fig. 6 shows a second embodiment of the sliding tape.

The glass panes 1 (FIG. 2) of a composite window are glued airtight and water vapor-tight onto a metallic hollow frame 2 by means of a butyl adhesive and are surrounded on the outside by a waterproof and mechanically load-bearing seal 3; this consists, for example, of a silicone or a polysulfide polymer.

A frame 7, covered with a film 6, is inserted as a self-supporting insulation element between the panes 1 through a spacer 4 and a spacer 5; the film 6 is provided in a known manner with a coating consisting, for example, of a metal, such as gold or silver, which is transparent in the visible spectral range and highly reflective in the infrared. While the spacers 5 each in the corners of the Cavities 2 are provided and have a recess in a corner for receiving the frame 7, the spacers 4 are glued distributed over the long sides of the frame 7 on its back facing away from the film 6.

In the torsionally rigid frame 7 according to the invention, the construction of which is described in more detail, a large number of individual sliding elements 8 ′ are inserted on one side as a sliding band 8 and are held displaceably relative to the frame 7.

As FIG. 6 shows, the sliding band 8 can also consist of one piece, the longitudinal extensibility of which is ensured by incisions 9 which are arranged at a distance and alternate from both edges.

The sliding band 8 or the sliding elements 8 'are connected to the film 6 via individual, interrupted adhesive spots 10, which are, for example, individual welding or adhesive spots.

The torsionally rigid frame 7 according to the invention has a closed hollow profile which has been produced, for example, by extrusion; the cavity of the profile is advantageously filled with a commercially available physical or chemical drying agent 11. Bores 22 in one of the cavity walls of the frame profile, preferably on the side covered by the sliding band 8, establish a connection between the drying agent in the interior of the hollow profile and the gas volume to be dried.

On one side of its square cross-section, the hollow profile carries on the outside a guide strip or slide-in rail 13 which is formed by bending over its elongated edges 12 for receiving the sliding band 8 or the sliding elements 8 '.

As shown in FIG. 5, however, a frame 17 can also have a profile such that the sliding band 18 or its elements are not pushed in, but rather are pushed onto a guide bar formed by longitudinal grooves 20, the displacement of the adhesion points 10 with respect to the plane of the stretched film 6 is ensured by a bead 19 present on the sliding band 18.

To the outside, the foils 6 protrude beyond the frame 7 beyond the adhesion points 10 in loose flaps 21. These flaps lie against the hollow frame 2 of the window in the case of insulation elements installed in the window (FIG. 1) and thus prevent outside air circulation around the frame 7 around between the two subspaces in the window separated by the insulation element.

Two mutually perpendicular sides of the frame 7 are each connected to one another by corner pieces 24 (FIG. 4) fitted into their hollow profile; for tensioning the frame 7, each side is supported at one end on the angle of the corner piece 24, while its other end can slide on one leg of a corner piece 24. The displacement of two mutually perpendicular sides takes place in the exemplary embodiment shown with the aid of a screw 25 which is screwed into a threaded bore 26 parallel to the leg of the corner piece 24 which forms the “slideway”. In the area of the "slideway" leg covered by the frame side to be displaced, the threaded bore 26 merges into a thread-free, open half-shell 27. By screwing in the screw 25, a gap of width s (FIG. 4) is created between the two frame sides during tensioning, for example, but is covered by the stretched film 6 (not shown in FIG. 4).

The corner pieces 24 fitted into the frame 7 simultaneously absorb the torsional forces acting on the frame sides at the ends of the frame sides due to the one-sided loading of the frame.

Around the train in the longitudinal direction of the film when the frame 7 is stretched as far out as possible on the edge and as parallel as possible to the edge, i.e. As far as possible in the longitudinal direction, the slide bands 8 and 8 'are arranged at the corners so that, as shown in Fig. 1, the line of action of the tensioning forces (arrow 28 in Fig. 1) at each corner perpendicular to the plane of the trap the supported side, advantageously through the last point of adhesion 10 '(FIG. 1) of this side and, if possible, in the axis of the points of adhesion 10 of the side perpendicular thereto.

Claims (6)

1. Self-supporting insulation element for insertion between the panes of a double or composite window, consisting of a single coated film which is biaxially stretched in the longitudinal direction and stretched over a tenter frame, the sides of which are bent in the untensioned state according to a curve curved on one side, characterized in that that the frame consists of a torsionally stiff profile that carries a guide bar (13, 20) on one side, through which at least one slide band (8, 8 '; 18) that is stretchable in its longitudinal direction is slidably held and guided along each side of the frame, and that furthermore, the film (6) is connected to the sliding band (8, 8 '; 18) via mutually separate adhesion points (10) in such a way that the adhesion points (10) are offset relative to the plane of the stretched film (6) towards the frame (7) are. 2. Insulation element according to claim 1, characterized in that the sliding band (8; 18) consists of a plurality of mutually separate sliding elements (8 '), each of which has at least one adhesion point (10). 3. Insulation element according to claim 1, characterized in that the torsionally rigid profile is formed by a hollow profile closed in the circumferential direction. 4. Insulation element according to claim 1, characterized in that the film (6) overlaps the tensioned frame (7, 17) beyond the point of adhesion (10) to the outside. 5. Insulation element according to claim 3, characterized in that the frame sides are stretched vertically displaceable at their corners over corner pieces fitted into their hollow profile. 6. Insulation element according to claim 5, characterized in that the displacement at least approximately by the last point of adhesion (10 ') of the sliding band (8, 8 ¹ ) on one side and at least approximately in the longitudinal axis of the points of adhesion (10) of the sliding band (8, 8 ') of the vertical side.

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