Technical field

The invention relates generally to the field of construction, and more specifically to window and door framework. More particularly, the invention relates to structures of frame profiles used in the manufacture of windows and doors. The object of the invention is also a window made of frame profiles characterized by a low heat transfer coefficient and high torsional stiffness, i.e. non-deformable during operation and during installation, which prevents loss of tightness to air infiltration.

Background

Design solutions for windows are known, wherein wooden parts are reinforced with pressed-in plastic spacers. Such a structure is characterized by reduced thermal conductivity, while the stiffness does not change due to the fact that the transverse dimensions do not change, and the shear moduli of wood and plastic are similar.

Also known are window profiles made of plastic, having two main supporting chambers and a few auxiliary chambers filled with air. These chambers reduce the heat transfer coefficient. The torsional stiffness of the frames made of such profiles is relatively low due to a high flexibility of the plastic. To increase the stiffness of large sized frames, rectangular cross section or plate-shaped cross section open steel profiles are for example inserted in the frames. It follows from the theory of torsion bars that open cross section bars have torsional stiffness several tens of times lower than analogous closed profiles. Accordingly, the stiffness of the window frame and casement frame would change slightly. The introduction of steel reinforcements virtually does not reduce (and may even increase) the heat transfer coefficient of window frames due to a high thermal conductivity of steel, and hence the thermal performance of the window would deteriorate.

To reduce thermal losses, frames with multi-chambered sections have been introduced, wherein plastic spacers with the conductivity coefficient lower than that of steel are used in the two main (largest) chambers, which reduces the heat transfer coefficient of the frame, while minimally affecting the stiffness of the structure.

Polish patent PL225174B1 discloses a method of manufacturing windows consisting of multi-chambered casement and window frame profiles. Openings are made in these profiles to suck air out of the chambers. The vacuum produced in this way in the chambers ensures better parameters of the thermal and acoustic insulation coefficient.

Another Polish patent PL184029B1 discloses a window design consisting of multichambered profiles of a window frame and a casement. Inside the chambers, metal reinforcement strips coated with a heat-reflecting layer are embedded, which results in a lower thermal conductivity coefficient.

Yet another Polish patent PL219804B1 discloses a window frame having window frame elements in the form of multi-chambered plastic profiles, reinforced with metal sections located inside the multi-chambered profile. In the chambers of the plastic profile, reinforcing and stiffening inserts made of a low thermal conductivity material, preferably wood, are inserted. Polish patent application P.383438 discloses a PVC window or door profile, made of walls forming in cross section a box structure with interior chambers in which a longitudinal reinforcing brace extending along the profile is inserted. The brace is made of a PVC-based composite material and a comminuted lignocellulosic material, preferably a wood powder.

Yet another Polish patent PL232782B1 discloses a window having a frame and a casement manufactured of multi-chambered PVC profiles, with metal reinforcing inserts placed in the space of some profiles.

Polish patent application P.404064, in turn, discloses a set of profiles with thermal reinforcement, comprising a frame profile and a casement frame profile. These profiles have a plurality of walls partitioning the profile interior into chambers extending along the longitudinal axis of the frame profile and the casement frame profile. One of the chambers houses a stiffening element with at least one reinforced wall and an insulating material remaining in contact with the stiffening element. The insulating material is a plastic insert, e.g. made of polyurethane foam, aerogel or polystyrene. The stiffening element is a metal section. This solution provides better bending strength in the plane parallel to the glazing surface.

Summary of the invention

The purpose of the invention is to provide a window design with a low heat transfer coefficient, but at the same time characterized by a high torsional stiffness.

According to a first aspect of the present invention there is provided a frame profile for the manufacture of windows and doors, having a plurality of chambers formed by a system of longitudinally extending walls, wherein in at least one of these chambers, at least along a part of its length, a stiffening element and an insulating material are inserted. The stiffening element is a closed section made of a textile material reinforced composite and filled with an insulation material.

Preferably, the textile material is made of natural or artificial fibres or a combination thereof.

The textile material is a woven fabric, and more preferably a glass woven fabric.

Preferably, the section is made of a composite that is a glass fibre based laminate.

Preferably, the stiffening element in the form of a closed section is located in the largest main chamber or in at least one smaller additional chamber.

Preferably, the stiffening element in the form of a closed section adheres closely to the inner surface of the chamber along its entire length, and the insulating material with a low heat transfer coefficient fills tightly the interior of the section.

According to a second aspect of the present invention, there is provided a window comprising a window frame and a casement frame, wherein the window frame or the casement frame is made of the frame profiles according to the invention.

The casement frame has glazing, preferably in the form of a single pane, a composite pane or a set of multiple panes.

Advantageous effects of the invention

The solution according to the invention allows to increase the torsional stiffness of window or door frames, which prevents them from warping and loss of air infiltration tightness, as well as to reduce the heat transfer coefficient, which in turn reduces heat losses.

Brief description of the Drawings The invention is presented in an embodiment in the accompanying drawing, wherein:

Fig. 1 - shows a window frame profile in a cross section.

Fig. 2 - shows a casement frame profile in a cross section.

Fig. 3 - shows an assembly of components from Fig. 1 and Fig. 2 into a window.

Detailed description of preferred embodiments of the invention

Fig. 1 and Fig. 2 show two embodiments of a frame profile according to the invention, wherein the frame profile shown in Fig. 1 is a profile of a window frame and the frame profile shown in Fig. 2 is a frame profile of a casement.

The frame profile 1 of the window frame shown in a cross section in Fig. 1 is made as a multi-chambered structure by joining a plurality of longitudinally extending walls 5 which divide the frame profile 1 into a plurality of air-filled chambers 3, 4. In this example, the frame profile 1 has a plurality of smaller additional chambers 4 and one largest main chamber 3. The frame profile 1 is mostly made as a single piece of plastic, usually PVC, by extrusion. In the main chamber 3, a stiffening element closely adhering to its walls is inserted, in the form of a closed section 6 with a cross section matching the shape of the main chamber 3 - in this case with a rectangular cross section. The section 6 is made of a textile material reinforced composite and filled tightly with an insulating material 7 with a low heat transfer coefficient, i.e. much lower than steel. In a preferred embodiment, the composite used to manufacture the section 6 is a fabric or generally textile material reinforced laminate. The fabric can be made of artificial or natural fibres or a combination thereof. Preferably, the laminate is formed by impregnating a glass fibre fabric with a resin, whereby a stiffening element with a very low heat transfer coefficient and a high torsional stiffness is obtained. The insulating material 7 that fills the profile 6 tightly is, for example, polyurethane foam.

The stiffening element in the form of a closed section 6 can also be inserted in one or more additional chambers 4.

The structure of the frame profile 2 of a casement, as shown in Fig. 2, is substantially the same as that of the frame profile 1 of a window frame of Fig. 1 and will therefore not be described in detail again.

Fig. 3 shows, in turn, a section through a window which comprises a frame profile 1 of the window frame of Fig. 1 and a frame profile 2 of a casement which is pivotally attached to the window frame. The frame profiles are connected to each other with gaskets 10. In the presented embodiment, both the frame profile 1 of the window frame and the frame profile 2 of the casement have a stiffening element, placed in the main chamber 3, in the form of a section 6 tightly adhering to the main chamber 6, made of a textile material reinforced composite and filled with an insulating material 7. In this embodiment, the casement has also a filling in the form of glazing 8 which is in the form of a glazing unit consisting of three glass panels. The glazing is installed in the frame profile 2 with a longitudinal strip 9 and gaskets 10.

The introduction of closed sections made of glass fabric based laminates significantly increases the torsional stiffness of a window element, which reduces warping of windows, especially the large sized ones.

The use of laminate sections filled with thermal insulation, where both the laminate and the thermal insulation have much lower heat conduction coefficients than steel, contributes to reduction of the heat transfer coefficient, and hence to reduction of heat losses in the rooms.