This invention is applied, to frameworks eg for windows having structural load-bearing profiles and external dressing (covering) in wood.

Background Art Various types of framework eg. with structural profiles dressed with interchangeable profiles of various materials are used.

The current technical solutions have integrated profiles that can not be dismounted, are robust, but have the drawback that the dressing is not interchangeable.

Other solutions have interchangeable dressing, generally in wood, by using a system of rotating clamps.

This solution is the closest alternative to the invention described hereunder, but has the drawback of being extremely complex during its construction, and requires considerable effort to be dismounted.

Sometimes it is even necessary to completely dismount the whole chassis of the frame to change the dressing.

There are other solutions with dressing profiles that attach to intermediate supports. The most complex problem, however, is the difficulty in dismounting the intermediate support and dressing profile.

Furthermore known profiles and frames are complex, expensive and, above all, have major assembly difficulties, and there are no substantial

guarantees regarding their structural, insulation and waterproofing properties.

Purpose of the invention The purpose of this invention is to overcome the aforementioned drawbacks.

Summary of the invention The problems are solved as claimed by a structural frame profiles dressed with interchangeable profiles, of the type in which: the load-bearing profiles have a means of hooking through a transversal elastic type push fit for an intermediate interconnection profile with joining means and counterpush; the interchangeable dressing laths are equipped with a means for fixing them to the intermediate interconnetion profile; characterised in that the said intermediate interconnection profile has elastic teeth on the internal side in order to hook to the corresponding teeth on the load-bearing profile, and can be unhooked for substitution by simply applying pressure.

In this way a very simple structure with interchangeable dressing is obtained, since the external structure can be unhooked by simply applying pressure Advantageously a composite profile for the frames is used. The composite profile is made up of a load-bearing section dressed with wood, characterised in that the load-bearing section has an intermediate plastic profile internally reinforced with a tubular structural section.

One side is externally dressed, while the other side is internally dressed with laths made of wood or other material. Two external parallel supports protrude from the intermediate structural profile. The ends of the supports have hooks that clamp, due to their plastic deformation, to

small teeth on the parallel supports (18) that protrude from the external dressing. This is then aligned with the intermediate structural profile due to the force generated by the lateral extremity of the internal supports that sit on the ends of the parallel supports of the external profile.

By using this method, frames that are perfectly functional, easily erected and dismounted and, above all, of excellent quality, structurally efficient with excellent insulation and waterproofing properties, are obtained.

Description of a means of applying the invention Description of means of applying the invention These and other advantages will appear in the following description of two solutions, the second one with reinforced-plastic inner profile, which, along with the included drawings, is to be considered simply a typical example of the application.

Figure 1 is a schematic sectional view of the profiles that make up the chassis in a joint between two double-glazed frames.

Figure 2 is a view of the joint of a door or window frame and a perimeter profile.

Figure 1 A is a sectional view of the composite profile on the perimeter side of the frame in the secondo solution with reingorced-plastic inner profile.

Figure 2A is a sectional view of the composite profile with reingorced- plastic inner profile, showing the connection between two sides of the frame.

As is shown in the drawings Figs. 1 and 2, the framework is made up of structural profiles dressed with interchangeable profiles, or load-

bearing profiles (3,4,5) and interchangeable dressing laths in wood or other material (1) characterised in that; the load-bearing profiles (3,4,5) have a means of hooking through a transversal elastic type push fit for an intermediate connection profile (2) preferably, but not necessarily, in plastic; the interchangeable dressing laths in wood or other material (1) have slots on the inside for a hooking means to the intermediate profile (2); the intermediate profile (2) has: on the inside, elastic teeth (22) to hook on to the corresponding teeth of the load-bearing profiles (3); on the outside, toothed pins or ribs (21) to fit inside the slots in the dressing (1).

An advantage of this system is that the load-bearing profile is L- shaped to act with a counter-profile that holds the glass (7) through a T- shaped base (6), the profile of which has a means for fitting an angular dressing lath (8).

A further advantage of this system for fixing the glass panels, or glass chamber (VC), is the use of push fit gaskets with spines on the rib and tapered enlarged heads (91,911).

Another advantage of this system is that the load-bearing profile (3) is in contact with an L-shaped intermediate load-bearing profile (4) through a gasket (92) which forms a sealed contact against the tongue of a U-shaped profile for added security (31), blocked internally to the main load-bearing profile (3).

Another advantage is that the U-shaped internal profile (32) turns back on itself to ensure contact between the gasket (92), having a corresponding external hook (321), and the structural profile.

In particular, the extension (3L) of the structural profile (3) has hooks on the inside (322) and, on the opposite side, thrust teeth (323) to act against the respective hooks (22) and counter thrust teeth (211) on the intermediate profile (2), with the respective seats (223,324).

This leads to a sure, tight fit To sum up: -from the metallic profile (3) two parallel feet protrude and have primary hooking teeth (222), primary contrast teeth (323) and primary support teeth (324); -in the plastic intermediate profile (2) corresponding elastic feet with teeth (22) are foreseen, and hook to the primary hooking teeth (322 -inside the aforementioned items, elastic feet (211) which sit and push fit on the contrast teeth (323) are foreseen, to provide a counter thrust; -inside the hook (22) of the intermediate profile (2) a support point (223) is foreseen and sits against the corresponding tooth (324) of the structural profile (3), placed at the end, externally at"L"to the foot (3L).

-this set up guarantees the constant alignment of the profiles (1,2,3).

-the feet (211) with a counterpressure on the intermediate profile (3), with respect to the external dressing profile (1), are able to slide inside the cavity of the feet (3L), freeing the hooking teeth (22) and allowing the separation of the intermediate and external profiles (2-1) from the structure (3), by simply extracting it.

The secondo solution with reinforcved plastic inner profile as shown in Figs. lA and 2A, disclose.

In these figures the preferred solution provides a composite profile for the construction of frames. It is made of a load-bearing wood- coated section, where the load-bearing section is an intermediate plastic profile (B) internally reinforced by a tubular structural section (X6). On

one side it is dressed by an external profile (C), and on the other by an internal dressing of laths in wood or other material (A). Two external parallel feet (XI) protrude from the intermediate plastic profile (B).

There are hooks at each end (X15) that hook, due to plastic deformation, to small teeth (X2) that protrude from the parallel feet (X18) of the external coating profile (C). It is thus aligned to the intermediate structural profile (B) due to the force generated by the lateral extremity (X16) of the internal parallel feet (X4) which sit on the ends (X3) of the parallel feet (X18) of the dressed external profile (C).

A further advantage is that the load-bearing profile (B) has a slot (X19) for traditional fixing systems and is an integral part of the load-bearing profile (B). The internal reinforcement is given by a tubular component with two or more fins (X5). These are necessary to clamp the stiffening profile (X6) and, at the end of the support (XI), a triangular tooth(X13).

The load-bearing profile (B) has a dedicated slot (X20) with teeth on the side (X21) which clamp a small V-shaped block (X10). A plastic profile (X9) is, in turn, hooked to the V-shaped block (X10). The plastic profile (X9) is joined at the border of the dressing (X22). The plastic profile (X9) has a soft fin (X8) that is compressed on the flat surface of the load- bearing profile (B), forming an air-tight seal.

Other small blocks are provided (X10,110) which snap on to the profile (B) by means of two fins (X23). One of the blocks is V-shaped (X10) with hooks at the two ends (X24), while the other block is U-shaped with a hook at only one of the ends (X25); both blocks (X10, X110) have a flat base (X26) that form a T with respect to the hooking fins (X23).

A fin (Xl 7) protrudes from the dressing profile (C) allowing the insertion of an angle-bar for lining-up purposes.

Gaskets are also foreseen, (X27, X28) to ensure insulation of the glass or panels and another gasket (XI 2) to form an air-tight and water-tight seal between the frame and the door or window. The gasket (X12) closes against the! ip (XH) of the load-bearing profile (B), while the gasket (X28) closes against the lower sill of the internal dressing lath (A).

The internal dressing lath (A) has a U-shaped or V-shaped groove (X7) according to the hooks (X30) of the load-bearing profile (B).

Obviously, the frame or structure with this composite profile forms the object of this innovation, being its end use, and is inclusive of the basic scope and final result.