A DEVICE FOR ATTACHING A WALL ELEMENT TO A BACKING STRUCTURE

Abstract: The present invention is related to a device for fastening a wall panel comprising at least an outer skin lining (1) and a thermal insulation (6) placed under said skin lining to a backing structure (5). Such a standard wall panel has at least one of the edges of the panel outer skin lining shaped into a tongue-and-groove joint surface (7) serving to join the panel to an adjacent panel. The fastening device comprises a claw clamp member (2) capable of gripping the tongue-and-groove joint surface of the outer skin lining (1) from under the panel edge joint, said claw clamp member (2) having a limited dimension in the thickness direction of the wall panel in order to avoid thermal bridging. This type of fastening device offers the benefit of efficient clamping of the panel against thermal expansion without using members remaining visible on the exterior surface of the finished wall.

Description: A device for attaching a wall element to a backing struc¬ ture The present invention is related to a device for attach- ing a panel-type wall element to a backing structure. The panel, for which the fastening device is designed, com¬ prises at least an outer skin lining and a thermal insul¬ ation placed under said skin lining. The fastening device is also suitable for mounting such a wall panel in which the outer skin lining is complemented with an inner ba¬ lance skin lining placed on the opposed side of the ther¬ mal insulation core. The skin is conventionally made from sheet metal, and mineral wool is used as the thermal in¬ sulation core. The outer skin members are fixed to the thermal insulation, advantageously by adhesive bonding. To make the wall panel resistant to wind forces and ther¬ mal expansion stresses, the panel must be fastened to its backing structure at least by its outer skin. A wall pa¬ nel having an inner balance skin may also be anchored by its inner skin lining to the backing structure. In such a wall panel, the corners of at least one edge of the panel are shaped so that the complementary shapes of the edge cornerε form a tongue-and-groove joint serving to join adjacent panels to each other. For aesthetic reasons, the such panels are preferably fastened to their backing structure so that no discerni¬ ble marks of the fixtures remain visible on the ready- installed exterior wall. This kind of mounting method presumes the fastening to be made using members that are embedded in the joint structure and concealed therein, such members being exemplified by the fastening member embodiment disclosed in the international patent applica¬ tion publication No. WO 89/12149. This approach is based on a fastening member designed to grip the tongue-and- groove joint edge of the panel, said fastening member being attached to the wall structure by means of a fas¬ tening system remaining concealed under the mounted pa- nels. The fastening member is shaped to fit between the tongue-and-groove joints of the wall panels being joined at their edges to each other. While the above-described fastening method is highly functional in terms of panel anchoring, it is hampered by the drawback that the fastening element remains in the tongue-and-groove joint formed by the adjacent mating surfaces of the skin linings, thus unavoidably causing an untight joint over those lengths of the joint between the panels that are not gapped by the fastening device. Furt¬ hermore, such a fastening arrangement uses a metallic member extending through the entire joint gap from the outer side to the inner side of the wall. This member thus acts as an effective thermal bridge, which particu¬ larly in this type of wall panel forms, in addition to the above-mentioned untightness of the joint, a shortco¬ ming in terms of fire resistance. From FI Pat. Appl. No. 940751 is also known a fastening member for wall panels, said member being comprised of a sheet metal fixture which is adapted to align longitudi¬ nally along the joint between the panels being joined and is moulded to a shape conformant with the cross section of the joint. One end of the fixture is shaped for ancho¬ ring to the backing surface, while the other end is bent for gripping the outer skin lining of the wall panel being installed, from under a pleat made to the edge of the panel. A wall panel comprising linings and a mineral wool core placed between them is inherently highly fire-resistant. In a properly erected wall, the thermal insulations should form a tightly abutting joint between the adjacent insulating panels, whereby the joint becomes tight with¬ out incorporating any fastening members capable of form¬ ing a thermal bridge through the joint. It is thus an ob- ject of the present invention to achieve a reliable fas¬ tening system for such wall panels that is capable of providing positive and indiscernible anchoring of the panels to a backing structure with a minimal impairment of thermal insulation at the joint between adjacent pa¬ nels. The goal of the invention is achieved by virtue of a fas¬ tening device comprising a claw clamp member capable of gripping the tongue-and-groove joint surface from under the panel edge joint and a fastening member suitable for anchoring said claw clamp member to the backing structure of the wall panel. The fastening device according to the invention is characterized in that, in the thickness di- rection of the wall panel, the dimension of the claw clamp member gripping the tongue-and-groove joint is smaller than the panel thickness. The fastening system disclosed herein achieves fastening of panels to a backing structure so that the interpanel joint will be free from members that could disturb an intimate mating of the tongue-and-groove joint surfaces of adjacent skin-structure panels. Those members of the fastening device that extend into the interpanel joint area can be adapted into such a region of the thermal insulation in the wall panels that can embed said members by yielding in a resilient manner, or alternatively, the edges of the thermal insulation can be provided with sui¬ table recesses to accommodate the gripping members of the fastening device. Then, the fastening device will not cause any disturbance to the tightness of a finished joint or impair its fire resistance properties. Further¬ more, the members of the fastening device will be mainly concealed within the thermal insulation against any stresses imposed by external heat. In the following, the invention will be explained in mo- re detail with reference to exemplifying embodiments il¬ lustrated in the attached drawings in which Figure 1 is a sectional view of a first embodiment of the invention suitable for fastening a wall panel to a back¬ ing structure; Figure 2 is a sectional view of a second embodiment of the invention suitable for fastening a wall panel to a backing structure; Figure 3 is a sectional view of the fastening system shown in Fig. 2, now with the adjacent wall panels joint¬ ed with each other; Figure 4 is a perspective view of fastening members used in the fastening system shown in Figs. 2 and 3; Figure 5 is a sectional view of a third embodiment of the invention during the mounting step of the panels; Figure 6 is a sectional view of wall panels mounted using the fastening system shown in Fig. 5; Figure 7 is a longitudinal side of a first half of a fas¬ tening member suitable for gripping the tongue-and-groove joint shown in Figs. 5 and 6; Figure 8 is a cross-sectional view of the fastening mem- ber shown in Fig. 7; Figure 9 is a longitudinal side of a second half of a fastening member suitable for gripping the tongue-and- groove joint shown in Figs. 5 and 6; and Figure 10 is a cross-sectional view of the fastening mem¬ ber shown in Fig. 9. Referring to Fig. 1, the embodiment shown therein is adapted for anchoring wall panels comprising a two-sided skin structure having a thermal insulation 6 placed bet¬ ween the lining skins. The linings are shaped at the re- gion of the panel edges into mating edges of a tongue- and-groove joint for the purpose of joining the panels with each other. During the installation of the panels, one of the panels is first fastened to the backing struc¬ ture by its edge. Then, the next panel will be correctly aligned in place simply by pushing the tongue-and-groove joint laterally home. In a first embodiment of the invention, the fastening de¬ vice incorporates a claw clamp member 2 shaped to firstly grip the tongue-and-groove joint from under the panel edge and to secondly accept an anchoring member which in the illustrated embodiment is a fixing screw 4. In the thickness direction of the wall panel, the dimension of the claw clamp member 2 is smaller than the panel thick- ness. In practice, the claw clamp member can be made into a continuous U-shaped section, whose one side is dimen¬ sioned suitable for slipping by virtue of the resilience of the thermal insulation 6 under the joint lip 7 pleated at the edge of the outer lining 1. The other side of the claw clamp section may be made slightly longer to provide a sufficiently strong attachment for a fixing screw 4. The screw 4 is dimensioned to extend essentially through the entire thickness of the wall panel, and thus, this screw 4 is the only metallic element passing through the interpanel joint essentially for the entire thickness of the wall panel. Said screw 4 can be directed for most of its length embedded in the thermal insulation 6 of the wall panel, where it remains protected against any stres¬ ses from external heat. For different applications, the design of the screw 4 can be varied suitably. In the il¬ lustrated embodiment, the screw is made self-tapping, whereby the screw can be driven first through any parts of the panels as required, and then, further through the backing structure 5 and finally tightened to exert a suf¬ ficient anchoring force. The claw clamp element 2 itself may be fixed in place into the tongue-and-groove structu¬ re 7 using, e.g., screws or similar fixtures driven through the skin lining 1. After the fastening step of the panel is completed, the adjacent panel is pushed in place by first aligning the mating surfaces of the inter¬ panel joint in the manner shown in the drawing. Referring to Fig. 2, a second embodiment of the invention shown therein has also the inner balance skin lining of the wall panel provided with a fastening device. This type of fastening device incorporates a second claw clamp member 8 corresponding to the claw clamp member 2 desig¬ ned for the outer skin lining. The claw clamp member 8 is shaped for slipping under the joint lip formed to the edge of the inner lining and is provided with a Z-fold or other suitable shape for accepting a fixing screw 11. In the illustrated embodiment, the fixing screw is shown driven onto the claw clamp member of the outer skin li¬ ning, whereby the other Z-fold of the member is shaped appropriately to accept said fixing screw. Alternatively, the claw clamp member 8 fastening the inner skin lining 9 can be attached directly to the backing structure 5. Referring to Fig. 3, a wall panel system anchored using the second embodiment of the invention is shown ready- installed. In Fig. 4 is shown an illustration of an exem- plifying shaping of the claw clamp members 2 and 8 used in a practical embodiment of the fastening device. In the embodiment shown in Figs. 5 - 10, two claw clamp members 2 and 3 are used that in paired cooperation with each other form a fastening device capable of anchoring the mating lips 7 and 12 of a tongue-and-groove joint of adjacent wall panels. These claw clamp members are fabri- eated into essentially U-shaped sections, in which one side of the section, namely, the claw clamp Z-folds 2 1 and 3 1 , respectively, is dimensioned to fit under the joint lips 7 and 12, respectively, formed to the mating edges of the outer lining 1 of the tongue-and-groove joint structure of the wall panel being installed. On the Z-fold 2 M opposed to the clamping Z-fold, one of these claw clamp members is provided with a hole 13 suited to accept a fixing screw 4. Correspondingly, the opposed the claw member 3 is dimen¬ sioned and shaped by its clamping Z-fold 3" to slip in springing manner under the opposed clamping Z-fold 2" when the panels are pushed together at their joint. To avoid collision with the fixing screw 4, the Z-fold 3" is provided with a compatible notch 14. The edges of the Z-folds 2" and 3", respectively, are advantageously sha¬ ped to provide guidance to the mating movement of the clamp members 2 and 3. Said claw clamp members 2 and 3 are advantageously made from continuous sections cut to lengths of about 20 - 30 cm, whereby one such length is used per each anchorage point of the joint. However, there is either no practical hindrance for making the claw clamp members 2 and 3 into full-length continuous sections extending over the entire joint and fixing the sections to the backing structure 5 of the wall panel at suitable spacings with screws 4. The above-described fastening system makes it possible to anchor a skin-structure wall panel equipped with mating tongue-and-groove joint edges at its edges to a backing structure at the interpanel joints so that each of the interjoining panels will be directly subjected to the fastening force of the fastening device and that the fi¬ nished interpanel joint is free from any discernible mem¬ bers or installation marks related to the fastening met- hod. A further important benefit is the minimized number of metallic, heat-conducting members extending through the entire thickness of the wall panel in the interpanel joint area.

Claims: Claims: 1. A device for fastening a wall panel comprising at least an outer skin lining (1) and a thermal insulation (6) placed under said skin lining to a backing structure (5) , said wall panel having at least one of the edges of the panel outer skin lining shaped into a tongue-and- groove joint surface (7) serving to join the panel to an adjacent panel, and said fastening device comprising a claw clamp member (2) capable of gripping said tongue- and-groove joint surface from under the panel edge joint and a fixing member (4) suitable for anchoring said claw clamp member (2) , which is locked to said tongue-and- groove joint (7) , to said backing structure (5) of the wall panel, c h a r a c t e r i z e d in that, in the thickness direction of the wall panel, the dimension of the claw clamp member (2) gripping the tongue-and-groove joint (7) is smaller than the panel thickness. 2. A fastening device as defined in claim 1 for use with wall panels also including an inner balance skin lining (9), c h a r a c t e r i z e d in that the fastening device incorporates a second claw clamp member (8) shaped to grip the tongue-and-groove joint surface (10) of the inner skin lining (9) of the adjacent wall panel from under and to accept a fixing element (ll) serving to at¬ tach said second claw clamp member (8) to said first claw clamp member (2) . 3. A fastening device as defined in claim 1, c h a r ¬ a c t e r i z e d in that said fastening device incor¬ porates a second claw clamp member (3) , which is shaped to grip the tongue-and-groove joint surface (12) of the outer skin lining (1) of the adjacent wall panel from under, and that both claw clamp members (2, 3) are shaped to interlock with each other during the mounting step of the wall panels. 4. A fastening device as defined in any of claims 1-3, c h a r a c t e r i z e d in that said fixing member (4) for anchoring said claw clamp member (2) to said backing structure (5) is a screw extending essentially through the entire thickness of said wall panel.

Inventors: RANTAKYLAE KARI, RANTAKYLAE, KARI
Applicants: PAROC OY AB, RANTAKYLAE KARI, RANTAKYLAE, KARI
Application year: 1996
Main classification: E04B1
IPC codes: F16B5