TITLE OF THE INVENTION:
WINDOW ELEMENT
TECHNICAL FIELD:
The present invention relates to window elements, such as window frames and window sashes, mor particularly such elements which are constructed from metal profiles and plastic foam keeping the profiles together.
BACKGROUND ART:
Window elements of traditional type, i.e. made from traditional timber wood, primarily pine and spruce, normally fulfil their function well in different building structures but are yet burdened with drawbacks. Thus, with increasing rationalization in the building technique there are difficulties in drying the timber for a sufficiently long time, so that when it has been put into place it does not move in an unacceptable manner, i.e. warp, with accompanying inconvenience. Furthermore, modern timber wood is associated with the disadvantage that for for example window element constructions one no longer selects so-called heartwood but utilizes the material irrespective of the manner of growth of the tree or part of the trunc as seen in cross section, whereby the construction relatively fast in view of influence of surrounding atmosphere will be destroyed by rotting, formation of fissures or the like. This is further aggravated by the fact that the price of wood during the last years has rapidly increased.
Against .this background there is thus a need for other types of window elements which can replace the traditional window elements based on timber wood.
SUMMARY OF THE INVENTION:
The, present invention has thus for its purpose to provide a window element which is not subjected to the traditional disadvantages of window elements and additionally can be prepared to competitive prices.
Another object of the invention is to provide a window element which can be made out of easily accessible raw materials.
For these and other purposes it has been found in connection to the birth of the invention that a quite useful window element can be produced starting from sheet metal profiles and plastic materials keeping same together.
For the use of the window element as a window frame it has in cross-section mainly rectangular shape and the outer part of the inner face is somewhat bevelled to facilitate water drainage. As seen in cross-section the window element in this embodiment is built up from at least two profile elements, one of which having largely U-shape with edge flanges bent inwardly over more than 90°. Also the other profile element has largely U-shape except the part forming the bevel, and also this profile element is provided with edge flanges bent inwardly over more than 90 and facing the edge flanges of the first-mentioned profile element. The two profileelements are kept together by means of foam plastic arranged in the space formed by the profile elements.
In this embodiment of the invention said other profile element in its intermediary part may be divided up Into two part elements each provided with its Inwardly bent edge flange, and between said part elements a window sheet can be Inserted or moulded in place in connection with the manufacture of the window frame.
In using the window element as a window sash it is designed with an essentially T-shaped cross-section. In
this case the element is built up from two profile elements, one of which has largely rectangular shape with the middle part of one long side taken away and the remaining parts being provided with longitudinally extending edge flanges bent inwardly over more than 90°. The second profile element has largely U-shape and is also provided with longitudinally extending edge flanges bent inwardly over more than 90° and facing the edge flanges of the first-mentioned profile element. As previously the profile elements are kept together by means of foam plastic arranged in the space formed by the profile elements.
In the window element according to the present invention it is preferred to arrange the edge flanges at some distance from each other to avoid formation of thermal bridges. In the gap between the edge flanges there may be arranged, if desired, a rubber or plastic ledge.
The plastics material arranged between the profile elements is suitably constituted by a hard foam plastic, and here it is preferred that the material is foamed up in situ between the profile elements in conjunction with producing the window element.
As a starting material for the hard foam plastic used as a plastic material there may be used any of the conventional materials, such as polystyrene, poly urethane, polyepoxy plastics, polyethylene, polyvlnyl chloride, cellulose acetate, phenol and carbamide resins or silicon plastics. Foaming may take place conventionally by using a foaming agent. In view of the fact that high strength is desirable it is preferred to use a foam plastic having a closed cell structure consisting of so-called integrated foam. A particularly preferred foam plastic is hard polyurethane foam, which can be produced while using a halogenated hydrocarbon as a
foam-forming agent..
The material in the profiles incorporated in the window element is preferably sheet metal, for example sheet steel, galvanized sheet steel, aluminium sheet metal or the like. In appropriate cases, however, the profile elements 3iay also be made from some other material, for example hard plastic. In using sheet metal as a material In the profile elements the thickness may vary from some tenths of millimeter up to around 1 mm. A preferred thickness is, however, within the range of about 0.25 to 0.75 mm, particularly about 0.4 to 0.6mm.
EXAMPLES:
The invention will in the following be described further by a non-limiting example in connection with the appended drawing. In same:
Fig. 1 shows a perspective view partly In cross-section of a window element according to the invention in the form of a part of a window frame; Fig. 2 shows a perspective view partly in cross-section of another embodiment of the window element according to the present invention, namely a part of a window sash.
In Fig. 1 there is shown in perspective part of a window frame designed in accordance with the invention. This window frame generally designated 1 has an essentially rectangular cross-section except for an outwardly facing bevelled part β intended to facilitate drainage of water. The window frame 1 is built up from three profile elements 3, 5, 7. The inwardly facing profile element 3 has U-shape and is provided with longitudinally extending inwardly bent edge flanges 9a,
9b, which, in the embodiment shown, are inwardly bent over about 150°, i.e. form an angle of about 30° to the corresponding part of the profile element 3.
Window frame 1 further includes a second profile element 5, one part 6 of which forms bevel of window frame 1. Also this profile element 5 is provided with longitudinally extended inwardly bent edge flanges 11a, lib.
Finally, the window frame 1 includes a third profile element 7. which is right-angled and is provided with longitudinally extending inwardly bent edge flanges 13a, 13b. The three profile elements 3, 5, 7 are assembled together by means of a foam plastic 15 in a manner shown in Fig. 1. Between opposite edge flanges 9a, 11a and 9b, 13b, respectively, there are interspaces 17 and 19, respectively, resulting in the advantage that thermal bridges do not exist between the inwardly facing part of window frame 1 and its outwardly facing part. Moreover, there is a gap 16 between edge flanges 11b, 13a the function of which is to enable arrangement of a window sheet not shown in Fig. 1 which can be either inserted afterwards in gap 16 or can be moulded in situ in connection with the manufacture of the window frame 1.
Window frame 1 of which only a part is shown in Fig. 1 Is in other respects designed in the traditional manner, i.e. in the form of a rectangular round-going frame with a bevel 6 facing outwardly. The joining of the part elements of the frame can be made in a wholly conventional manner, either by joining the corners with 45° chamfer or while using right-angled joints. The assembly can be made by gluing and/or screwing or any other traditional manner.
Fig. 2 shows the building element according to the invention designed as a window sash. The window sash, generally designated 18, has a general T-shaped cross-section. The window sash includes two profile elements 20, 22, one 20 of which has twice over 90º bent
edge sections 21a, 21b provided with longitudinally extending inwardly bent edge flanges 24a and 24b, respectively, the bending angle of the embodiment shown being largely the same as that shown in Fig. 1. The second profile element 22 has a U-shaped cross-section and is provided with longitudinally extending edge flanges 26a, 26b bent Inwardly In the same manner.
The profile elements 20, 22 put together according to Fig. 2 are kept together by foam plastic 13 foamed in situ in the space between same. The profile elements 20, 22 are assembled under the formation of a gap 28 between the longitudinally extending edge flanges, thereby avoiding the drawback of the formation of a thermal bridge between the inwardly facing part of the window sash and its outwardly facing part. In this gap 28 a rubber or plastic ledge can be moulded in situ for example for sealing purposes.
Window sash 18 is otherwise arranged in a traditional manner, i.e. rectangularly framing two or three window glass panes. The window sash is designed to cooperate with the window frame shown in Fig. 1, the lower part of profile element 20 sealingly cooperating with the rear-upper edge of window frame 1. The opposite side of window sash 18 Is designed to hold a frame for example of light-weight metal surrounding the window sheets, the frame being arranged in the space on the upper side of window sash 18. The part-elements of window sash 18 can be jointed in a conventional manner, for example with 45 chamfer at the corners or with right-angled joints, the attachment being obtained by for example gluing and/or screwing or the like.
The advantages of the window element according to the invention are many. Thus, the window element can be produced at a comparatively low price and be made with any cross-section and any length. Furthermore, in using
the window element the formation of thermal bridges is avoided as. a rule, the cohering foam plastic serving as an insulation. Moreover, the window element according to the invention, gives a very good strength. It should be noted that the .Invention is not limited to the embodiments shown above but can be modified in several respects within the scope of the invention. Thus, the bent edge flanges can be formed in a multitude of ways as long as they are bent at least about 90 for anchoring in the plastic material. Moreover, they can have double bends "to provide even better anchorage. Furthermore, the cross-sectional form of the window element can be varied arbitrarily.