A DOUBLE-GLAZED PANEL FOR THE BUILDING AND FURNISHING INDUSTRIES, AND PROCESS DESCRIPTION The invention relates to the field of building and furnishings. In the building and furnishing industries, vertical or subvertical walls made of glass panels with various functions are used. In particular, the problem at the basis of the invention will be set forth with reference to the so-called"structural"walls or façades comprising coating or cladding panels made of glass plates (or plates of other materials) applied on a supporting framework of the wall. In detail, reference will be made to façades made of glass elements or panels or insulating glazings of a type known as"double glazing". These comprise two parallel glass plates with a gap therebetween and connected together along a peripheral frame, or a frame near the periphery, by means of an adhesive or bonding agent, generally a silicone cement, referred to more briefly as"silicone", or preferably a "silicone"having particular features of mechanical strength that remain constant over time, known as"structural silicone". The gap is kept dry by interposing a beading containing a de-humidifying material.

The walls made up as described above must satisfy two conflicting requirements; i. e., they must guarantee maximum safety and durability and, at the same time, have an attractive appearance according to the current requirements of architectural standards, that is, the supporting structure must be practically invisible.

A large variety of systems have been designed to solve the problems referred to above. In what follows, a few of the ones deemed more important are recalled.

One known system involves the use of a section bar applied to the double-glazed panel on the entire perimeter of the latter. The section bar comprises a flange with supporting parts for the two glass plates, and a channel-shaped intermediate part, which is set between the two glass plates within the silicone, as well as a second flange with fixing means for fixing to a supporting framework.

Another known system involves the insertion, in the structural silicone around the periphery of the panel, of a metal bar provided with a longitudinal groove having internal scores for fixing to a section bar of a supporting framework.

These known systems achieve a good mechanical retention on the inner glass plate of the panel, whilst the outer glass plate is connected to the inner glass plate and to the metal section by means of a peripheral bead of structural silicone. It has been proved that, whilst the adhesion of the structural silicone to the glass is reliable and durable, the adhesion of the structural silicone to the metal presents several uncertainties, particularly as regards its durability.

In the event of breakage of the inner glass plate of the panel (which is frequently made of tempered glass, and hence breaks into small fragments), the outer plate would remain anchored only to metal surfaces by means of structural silicone, with all the risks that this involves.

The applicant proposes a solution to the problem outlined above with the invention that fonns the subject of the present application, as expressed in Claim 1. Further new and useful characteristics are said in the dependent claims.

In other words, according to this application, a glazed or glazing panel of the double- glazing type, which comprises two parallel glass plates connected together by a bead of adhesive cement set between them, comprises, in the compartment delimited by the edges of the said plates, a retaining means that includes a metal section bar and a surface of <BR> <BR> <BR> "consistent"or"compatible"material, or the like, a bead or portion of"consistent" cement being provided at least between the said"consistent"material surface and the outer glass plate of the said glazing panel.

A"consistent"or"compatible"material, a"consistent"or"compatible"sealing means or adhesive are here defined as a material, respectively sealing means or adhesive, which show a good bonding or adhering action when are bonded/adhered together, i. e. wherein the adhesion of the sealing means or adhesive on the material is good and durable; as examples of"consistent"means, glass and structural silicone are here mentioned. The said surface of"consistent"material is generally a surface of a rod retained within the metal section.

Preferably, the glazing frame is prefabricated, with the section bar and the rod, in glassworks or glassworkers shops, so that it can be easily installed in the supporting framework in situ. According to a variant, however, it is possible to assemble a

traditional double-glazed panel in the glassworks, and subsequently apply the retaining means in the factory.

The invention enables an excellent retention to be achieved for the outer plate of the glazing panel around the entire periphery of the latter, with optimal working conditions for the silicone cement, even in the event of breakage of the inner glass plate.

Examplary embodiments of the invention will be described in the following, with reference to the attached figures, in which: <BR> <BR> <BR> <BR> <BR> -Fig. 1 is a schematic front view of a glazing frame on a reduced scale;<BR> <BR> <BR> <BR> -Fig. 2 is a cross-sectional broken-away view along a plane 2-2 of Fig. 1 of a first embodiment of a double-glazed glass panel according to the invention mounted on a section bar of a supporting framework, this too being shown broken-away; <BR> <BR> <BR> -Fig. 3 is a cross-sectional view along a plane indicated by 3-3 in Fig. 1, interrupted;<BR> <BR> <BR> <BR> -Fig. 4 is a broken-away perspective view, on a reduced scale, of a retaining means used in the first embodiment; <BR> <BR> <BR> -Fig. 4a is a perspective view of a variant of the retaining means;<BR> <BR> <BR> <BR> -Fig. 5 is a broken-away cross-sectional view, similar to that of Fig. 2, of a second embodiment of the glazing pane of the invention; <BR> <BR> <BR> -Fig. 6 is a broken-away perspective view, on a reduced scale, of the retaining means used for the panel of Fig. 5; <BR> <BR> <BR> -Fig. 7 is a cross-sectional view of a further embodiment of the panel;<BR> <BR> <BR> <BR> -Fig. 8 is a perspective view of the retaining means of Fig. 7;<BR> <BR> <BR> <BR> -Fig. 9 is a sectional view, similar to Fig. 2, of a modified embodiment;<BR> <BR> <BR> <BR> -Fig. 10 shows the embodiments of Fig. 2, wherein a pin-shaped fixing means has been shown.

In the present text, by the term"adhesive""bonding agent"or"cement"is meant any material suitable for holding joined together glass plates. By"silicone"or"silicone cement"is meant a silicone-based adhesive material, as is normally used in the glass- production sector. By the term"structural silicone"is meant a per se known material, which has particular durable qualities of strength. By the term"glazing panel"or"glazing pane"is meant a component element for a wall; the wall may be a glazing-panel façade, a partition wall, a decorative wall for indoor furnishing, or something else of the sort. By the term"double glazing"or"insulating glazed panel"is meant a panel that comprises

two glass plates with a de-humidified air gap, obtained by interposing between the glass plates a mechanical retaining means provided with a cement, preferably, but not exclusively, silicone cement or structural silicone, and a beading containing hygroscopic material. In the examples, reference is made to a structural façade; the glass plate of the glazing pane designed to face towards the supporting structure is designated as"inner" glass plate, the glass plate on sight as"outer"glass plate.

With reference first of all to Figs. 1 to 4, an examplary glazing pane 10 of the invention comprises a first"inner"glass plate 12, a second"outer"glass plate 14, possibly with a peripheral bevel 15, separated from one another by a gap 13, and joined together by means of a layer or bead of adhesive cement or sealant 16, generally silicone or structural silicone. The gap between the glass plates is kept dry, in a per se known way, by a beading 18 containing a dehumidifying material.

According to the invention, the panel 10 comprises a retaining means, referenced 20, accommodated completely, or almost completely, in a peripheral space between the glass plate 12 and the glass plate 14. In the embodiment illustrated in Figs. 1-4, the retention means 20 comprises a metal section bar or strip 21 and a glass rod 22. The section bar 21 is preferably connected by means of a bi-adhesive material 23 (or silicone bed or glazing putty) to the face of the inner plate 12 facing towards the gap. The material 23 may be of any known type; its function is only to hold the metal section bar 21 in position until the latter is fixed.

The section bar 21 in the embodiment of Fig. 1 has a C-shaped or channel shaped cross section, with rounded edges or lips of the C facing one another for a length. In a longitudinal space delimited by the C, the channel shaped section bar receives the glass rod 22. The glass rod 22 may be a continuous rod or may be made up of a number of adjacent rod portions. The rod 22 is accommodated with clearance in the space defined by the channel section and is firmly held in the channel section by means of filler material 25. The filler material 25 may comprise one or more of the following materials: adhesive cements, silicone, glazing putties, sticking plasters, strips of nylon sheet.

Between the facing surfaces 21'and 21", of the flanges of channel section or section bar 21, a wide surface of the glass rod 22 remains exposed. A structural-silicone sealing filler material 26 is set between the face of the outer plate facing the inner plate, the channel section 21 and the glass rod 22. Note that, even though a distinction is indicated between

the adhesive cement body 16 which defines the double-glazing panel and the structural- silicone body 26 which fixes the plate 14 to the rod 22, in actual fact, it is possible and preferable to have a single body 16,26 of structural silicone without any apparent separations.

The double-glazing panel 10 comprises the retaining means 20 preferably around its perimeter ; possibly, only on portions of its sides.

The channel section 21 is fixed with traditional fixing means not shown (generally engaging its back, where it is thicker), to a section bar P, of a supporting framework of a curtain wall or similar façade. Preferably the section bar P has a flange extended out to the outer glass plate 14 of the panel. The fixing means may include, e. g. screws and threaded holes in the section 21.

Whereas Fig. 2 shows a bottom edge of panel 10, Fig. 3 shows a top edge or a side edge of the same panel. Along the top edge or side edges, the plate 14 projects beyond the plate 12 for a length, and the section bar Pa of the supporting framework extends up to a certain distance from the plate 14. Elements referenced 21a, 22a, 23a, 25a are the same as elements 21,22,23, and 25, described above for Fig. 2.

It may be noted that in this way the panel 10 is fixed by fixing and mechanically supporting inner glass plate 12. The outer glass plate 14 is supported, as regards vertical loads, on the section bar P and is stably held in position by means of the cement 16, with a glass-to-glass fit over an area in which the silicone compound 16 is present, and by means of structural silicone 26, with a glass-to-glass fit over an area of the rod 22 (or 22a). In the event of breakage of the glass plate 12, the glass plate 14 remains even so firmly fixed.

Figure 4a shows a modified embodiment of the channel section, designated by 21a. The section 21a does not provide an upper lip facing an opposite lip of the channel section.

Note also that the section bar 21 may be used turned upside down with respect to the position illustrated in the figure.

In the embodiment of Figs. 5 and 6, a glazing panel 110 comprises an inner glass plate 112, an outer glass plate 114 with peripheral bevel 115. An inside gap 113, between the two glass plates is kept de-humidified by a hygroscopic means contained within the

beading 118. The plates 112 and 114 are joined together by an adhesive cement body 116. All the elements described are similar to those of the previous panel. The panel 110 comprises a retaining means 120 with an exposed glass surface. The retaining means 120 comprises a section bar 121 and a glass plate 122 accommodated in the section bar 121 by filler means 125. The section bar 121 is held on the inner plate by means of a bi- adhesive or bonding agent or silicone 123. The section bar 121 has a shape with a thickened bottom part, for engagement with traditional fixing means (not shown), which, in the embodiment of Figs. 1 to 4, were engaged in the thickened back of the section bar.

A layer of structural silicone 126 is laid between the outer plate 114 and the retaining means 120. Figure 5 shows the bottom edge of the panel 110. The side and top edges can be easily understood by referring to Fig. 3 and do not require further description.

In a panel 210 of Figs. 7 and 8, the same elements as those of the panel shown in Fig. 1 bear the same reference numbers increased by 200 and will not be described in detail.

The retaining means 220 comprises a U-shaped section bar 221 and a glass rod 222 partially accommodated therein and projecting from it at the top. A filler material 225 is provided. The reference 223 is a bi-adhesive means or the like, as described above with reference to the means 23. The reference 226 indicates the structural silicone. Also in this case, the side and top edges of the panel will have the outer glass plate protruding, as shown in Fig. 3.

In the embodiment of Fig. 9, which is a variant of Fig. 2, the same reference number as in Fig. 2 have been used for the same elements, which will not be further described. The rod of the retaining means in this embodiment is referenced 22a and comprises a protruding spline-like portion on one side, so as to have a surface substantially flush with the outer surface of section bar 21.

In the embodiment shown in Fig. 10, the same reference numbers as in Fig. 2 have been used, and a pin-shaped means 27 has been shown, for fixing together a section bar P of the framework and a section bar 21 of the retaining means. A plurality of means 27 are integral to section bar P and the double-glazed panel engages thereon by means of recesses in section 20.

Though the above exemplary embodiments have been described with reference to a glass or glass-type material for rod 22 (122; 222) and to structural silicone for bonding or sealing material 26 (126; 226), the scope of the invention is intended to include a

combination of a rod and a bonding/sealing material made of"consistent"or "compatible"materials as said above, also different from glass or structural silicone.

According to a preferred embodiment of the invention, the entire panel or pane 10, or respectively 110 or 210, comprising the retaining means 20, or respectively 120 or 220, is manufactured in a glassworks and assembled on site on the sectional strips P. However, the invention also contemplates that the retaining means is applied in a factory on a traditional double-glazed panel produced by the glassworks.

It may be noted that, even though the preferred retaining means of the invention is at present a metal sectional strip with a glass rod, also different retaining means are comprised within the scope of the invention, provided that they have a surface at least partially vitrified or glazed.