EP0905330A2

EP0905330A2 - Connection device for infill panels

Info

Publication number: EP0905330A2
Application number: EP98117401A
Authority: EP
Inventors: Alberto Dal Lago
Original assignee: Ruredil SpA
Current assignee: DLC SRL
Priority date: 1997-09-26
Filing date: 1998-09-14
Publication date: 1999-03-31
Anticipated expiration: 2018-09-14
Also published as: ES2256906T3; EP0905330A3; ATE315695T1; EP0905330B1; ITMI972193A1; DE69833153D1; IT1295087B1

Abstract

A connection device for prefabricated infill panels which connects a supported outer layer (1) to a supporting inner layer (2) without interrupting the continuity of the insulating layer (3) or of a ventilation chamber; this connection device for the two layers (1, 2) comprises for the supported layer (1) a support element (4) which by applying a guide also becomes a unidirectional sliding element for the differential expansion of the two layers, and also comprises retention elements (6) which allow even considerable relative sliding of the two layers in every direction without fatigue phenomena arising.

Description

This invention relates to devices for connecting together a supporting layer and a supported layer, separated by continuous insulation or by an air chamber, in infill panels, in accordance with the pre-characterising part of the respective independent claims.
To connect the outer and inner layers together, it is known in the art to use a single support device positioned at the barycentre of the suspended layer in order to maintain continuous insulation without thermal bridges and avoid making between the two layers a rigid connection which would result in both temperature variation and unacceptable deformation in the plane in which the panel lies. This device must be able not only to support the entire weight of the supported layer, but also to resist the inevitable torsion to which the outer layer is subjected during removal from the mould, handling and installation. In this respect, the panel produced lies horizontally during its removal from the mould whereas it lies vertically with its longer side horizontal during storage, and during installation can undergo a vertical 90° rotation so that the longer side lies vertically.
The known support device, which passes through the entire thickness of the insulation to rigidly connect the outer layer to the inner layer only at one point, requires the provision of a plurality of "lacing" members in the form of retention elements inserted into the casting to prevent the two layers separating from each other while enabling them to slide to a limited extent due to temperature variation.
It should be noted that because of the presence of a central connection member between the layers , numerous retention elements have to be positioned a short distance from each other to allow the panel to be removed from the mould and handled. The central connection device and the perimetral retention devices have numerous drawbacks. The first is that relating to heat transmission. In this respect, because of the dimensions of the central device and the fact that it passes totally through the panel (ie the supporting, supported and intermediate layers), it creates a thermal bridge which generally considerably reduces the thermal insulation characteristics of the panel. In addition, essentially because of their large number the retention devices also cause further by no means negligible heat dispersion. A further drawback of the known connection system relates to the fact that, depending on the thickness of the supported and supporting layers and of the insulating layer, support and retention devices constructed and sized for the purpose must be used. It is therefore necessary to produce support and retention devices of different dimensions to satisfy design specifications. This inevitable affects the order time and involves the need to hold in store devices dimensioned for a vast range of thicknesses of the supporting, supported and insulating layers.
An object of this invention is to provide a system for connecting the two panel layers together which reduces heat dispersion to a minimum and uses support and retention devices of the same dimensions for any type of panel, ie which are designed for forming panels in which the supported layer, the supporting layer and the insulation of air chamber are of variable thickness. In addition to the support device, the connection system comprises a retention device allowing unidirectional movement plus retention devices able to withstand a considerable weight during removal from moulds and, whatever the insulation thickness, to always allow a high degree of movement between the two layers (ie movements of the order of 2 cm, which are normal for the temperature difference between the outside and inside in panels of more than 10 metres in height), so as to drastically reduce the number of retention devices compared with the known art, but without any loss in functionality.
This and further objects which will be apparent to an expert of the art are attained by a connection system consisting of a support device which can also become a unidirectional sliding device, and by retention devices in accordance with the characterising part of the independent claims.
The invention will be more apparent from the accompanying drawings, which are provided by way of non-limiting example and on which:
Figures 1 and 2 are schematic front views of a panel of the invention positioned vertically and horizontally respectively;
Figures 3 and 4 are schematic sections through two support devices of the invention, taken on the lines 3/3 and 4/4 of Figure 2 respectively;
Figures 5A-C are three mutually perpendicular schematic views of a first support device;
Figure 6 is a schematic view from above of a second support device;
Figures 7A, B are respectively a schematic front view and a section on the line 7B/7B of Figure 6, showing a guide element far the second support device;
Figure 8 is a partly sectional schematic view of a retention device of the invention;
Figure 9 is a schematic section through the retention device taken on the line 9/9 of Figure 2.
Figures 1-4 show a prefabricated infill panel comprising a supported outer layer 1, a supporting inner layer 2, and an insulating intermediate layer 3. The panel layers are separated by continuous insulation or a thermal cut-off and are constructed of usual materials for this purpose, such as concrete or other similar material. The insulating layer is constructed for example of a polystyrene or polyurethane insulating material, or is in the form of a ventilated air chamber or a combination of insulation and an air chamber. Advantageously, the supporting layer 2 can also comprise a lightening insert 2A, for example polystyrene. To secure the layers 1 and 2 together the panel comprises fixed support devices (Figures 3 and 5A-C), support devices partly slidable unidirectionally (Figures 4, 6, 7A, 7B), and retention devices 6 (Figures 8, 9). The fixed support devices 4 comprise a substantially pin-shaped body 8 (Figures 5B, 5C), for example a 40 mm diameter rod of galvanized or stainless steel. In the present contest the term "pin" means an elongate body with a cross-section of any polygonal shape (circular in the example).
At that end 8A to be embedded in the supporting layer 2, the pin-shaped body 8 comprises a recessed annular portion 7 (Figures 5B, 5C) for improving the anchoring of the body within the panel. At the other end 8B of the body 8 there is provided a T-shaped (in front view) fixing head 9 of greater width L than the pin diameter D and joined lowerly to the pin body 8. The head 9, which has a greater surface area than the body of the pin, performs simultaneously the function of distributing the weight of the outer layer over a greater metal surface and of anchoring the device to the suspended layer.
If the static calculations require it, a concrete reinforcement element 10, which is in the form of a spring in the example (Figures 3, 4, 6), can be secured to the pin body 8. In the described embodiment, this element rests against a disc 11 (Figure 6) which before the supporting layer is cast can slide along the body of the fixed pin and abut against the inner wall 3A of a pocket 3B provided in the insulating material. As shown in Figures 3 and 4, for correct fixing of the pin into the supporting panel 2, that portion T (Figure 6) of the body 8 lying between the disc 11 and the end 8A must be totally embedded in the concrete. For this purpose, if necessary, a part of the insulating layer is removed in order to form the pockets 3B (as shown in Figures 3 and 4). In this manner, the pin always has a fixed nominal loading capacity, independently of the thickness of the insulating layer.
It should also be noted that, as shown in Figure 3, the pin does not totally pass through either the supported panel 1 or the supporting panel 2, but penetrates into and engages only a distance M of the thickness S1 of the supported panel and in addition has an insulating disc at its front. In this manner the pin reduces to a minimum the "thermal bridge" between the outside and inside of the construction element, to ensure a more effective thermal insulation the known devices.
The support device with unidirectional sliding 5 comprises a body 8 identical to that of the aforedescribed device 4, the head 9 being however inserted into a rectilinear guide 12 having a C-shaped profile to engage the head 9 of the pin, so that when installed the pin is able to undergo a longitudinal movement along the guide, but not a transverse movement relative to the guide.
When the head 9 has been inserted into the central part of the guide 12, this latter is filled with a conventional foam able to prevent the guide becoming filled with concrete. The guide and its relative associated pin are then embedded in the supporting panel with the guide arranged parallel to the longer side of the panel, for example along the central line L (Figures 1 and 2).
By virtue of this device, the supported layer can freely expand longitudinally, without any deformation of the entire panel due to prevented expansion, and which remains always supported by the support devices. In the case of a vertical panel, as in Figure 1, the supported panel can be connected for example by providing two fixed connection pins 4, which carry all the weight of the supported layer in two central positions indicated by the arrows C, and two unidirectional sliding pins 5 in two more extreme positions, indicated by the arrows E, but lying on the same longitudinal line L on which the fixed pins are provided.
In the case of horizontal panels, as in Figure 2, it is sufficient to provide a single central fixed device (indicated by the arrow C'), in addition to the unidirectional sliding devices 4 in the positions E. This is because in this case the unidirectional sliding devices are also supporting.
The retention devices 6 comprise substantially a flexible cable 13, for example of 4 mm diameter stainless steel, bent to form an eyelet 13' and closed for this purpose by a ring or splice 14.
A central portion of the cable is housed in a plastic tube 15. This tube is pointed at one end, and at its other end comprises a collar 15A acting as a stop for a cylindrical spacer 16 mounted on the tube and constructed of a yieldable and easily cut material, such as polystyrene. The ends of the cable 13 could also be untwisted (as in Figure 9). The spacer 16, of previously adjustable depth, enables the device to be accurately positioned relative to the position of the insulation. It should also be noted that the use of a stainless steel cable instead of a stainless steel rod as in the known art offers a much higher resistance to traction and does not present the problem of fatigue due to the daily temperature cycles, so allowing larger displacement of the supported layer relative to the supporting layer. Moreover, for equal performance, the number of retention devices required is much reduced, with considerable saving both in working time and in material cost. The smaller number of retention devices results in reduced heat dispersion. Moreover, as can be seen from Figure 9, the retention devices are of fixed dimensions, and hence independent of the insulation thickness. In this respect, the dimensions of the spacer 16 can be modified if the thicknesses of the layers 1, 2, 3 makes it necessary.
By virtue of the connection system formed by the fixed support devices 4, the sliding support devices 5 and the retention devices 6, according to the invention, panels can be formed which do not deform outwards, and offer high insulation and/or ventilation, with thermal bridges absent. The same support and retention devices 6 can also be used on panels of different supported layer, supporting layer and insulating layer thicknesses.
Both the connection devices 4 and 5 and the retention devices 6, according to the invention, could also be used in combination with retention devices or support devices of the known art respectively.
Finally, it should be noted that the aforedescribed embodiment is provided by way of non-limiting example and that numerous modifications are possible all falling within the same inventive concept, for example the form of the head 9 or of the anchoring end 7 could be different from that illustrated, and the spring 10 could be replaced by other reinforcement elements conventional to the expert of the art, for example one or more logs extending from the body 8. In addition, instead of in the guide 12 the head 9 could be inserted in a rectilinear element of yieldable material, for example a polystyrene parallelepiped having substantially the same dimensions as the guide 12. Finally, the cable 13 could be replaced by another conventional element suitable for the purpose, for example flexible braiding.

Claims

A support device for infill panels, particularly of prefabricated type constructed of concrete or similar material, which comprise a supported outer layer (1), a continuous intermediate insulating layer (3) and a supporting inner layer (2), the device being arranged to connect the two layers (1, 2) together, characterised by comprising a pin (8) to be inserted into the two layers (1, 2) and into the insulating layer (3) and be embedded at least in the supporting layer, and by being formed in such a manner as to be able to support the weight of the supported layer (1) or support the weight of the supported layer (1) and to allow the supported layer (1) to slide unidirectionally relative to the supporting layer(2).
A device as claimed in claim 1, characterised in that at that end (8B) inserted into the supported layer the pin (8) comprises a head (9) formed in such a manner as to be able to act both as an anchoring element when the head is embedded in the concrete of the supported layer (1), and as a slidable element when said head is associated with a guide element (123) embedded in the concrete of the supported layer (1).
A device as claimed in claim 2, characterised in that the head (9) has greater transverse dimensions than the transverse dimensions of the pin.
A device as claimed in claim 3, characterised in that the head (9) is substantially of T-shape.
A device as claimed in claim 2, characterised in that the guide element has a profile (12) of substantially C-shaped cross-section enabling the head (9) of the pin (8) to slide unidirectionally.
A device as claimed in claim 2, characterised in that the guide element comprises a rectilinear insert constructed of yieldable material.
A device as claimed in claim 1, characterised in that in correspondence with that portion embedded in the supporting layer (2), the pin (8) comprises a concrete reinforcement element (10) connected to the body of the pin and extending from said body.
A device as claimed in claim 7, characterised in that the reinforcement element comprises a spring (10) slidable along the body of the pin (8).
A device as claimed in claim 1, characterised in that in correspondence with that portion thereof embedded in the supporting layer (2), the pin comprises anchoring means (7).
A device as claimed in claim 9, characterised in that at that end (8A) of the pin (8) inserted into the supported panel (2), the anchoring means comprise a recessed portion (7).
A device as claimed in claim 1, characterised in that the pin is shaped in such a manner that its ends (9, 8A) lie completely within the interior of the two layers (1, 2), and are invisible from the exterior of the construction element.
A device as claimed in claim 1, characterised in that the pin has a substantially cylindrical body (8).
A retention device for infill panels, particularly of prefabricated type constructed of concrete or similar material, which comprise a supported outer layer (1), a continuous intermediate insulating layer (3) and a supporting inner layer (2), the device being arranged to connect the two layers (1, 2) together, characterised by comprising at least one flexible cable (13) formed in such a manner as to be able to be anchored into the supported layer (1) and into the supporting layer (2).
A device as claimed in claim 13, characterised in that the cable (13) is bent to form an eyelet (13)' at one end and comprises an element (14) for closing said eyelet and for acting as a stop for a tubular element (15) in which part of said cable is inserted.
A device as claimed in claim 13, characterised in that a spacer element (16) is mounted about that portion of the cable (13) embedded in the supporting layer (2).
A device as claimed in claim 15, characterised in that the spacer element is formed in such a manner as to be able to vary its dimensions so that it can be adapted to various thicknesses of the panel insulating layer (3).
A device as claimed in claim 14, characterised in that the tubular element (15) has one of its ends pointed, to enable it to be inserted into the insulating layer (3).
A method for connecting together a supported outer layer (1) and a supporting inner layer (2) of an infill panel comprising said layers (1, 2) separated from each other by a continuous insulating layer (3), characterised by securing the supported layer and supporting layer (1, 2) together by at least a first fixed central pin (4) embedded in the two layers, and passing through the insulating layer (2), such that the ends of said pin lie within said layers, and at least one second pin (8) having one portion embedded in the supporting layer (2) and another portion arranged to slide unidirectionally within a guide element (12) embedded in the supported layer (1).
A method as claimed in claim 18, characterised in that the two pins, namely the fixed pin and the slidable pin, are positioned along a longitudinal line (L) of the construction element, the slide means being positioned in such a manner as to allow at least partial sliding of the supported panel (1) along a direction parallel to said longitudinal line (L).
A method as claimed in claim 18, characterised in that the fixed and slidable pins (4, 5) are embedded in the two layers (1, 2) in such a manner as to be invisible from the exterior of the construction element.
A method as claimed in claim 18, characterised in that within the insulating layer (3), in correspondence with the pins (4), there is provided a pocket (3B) in order to be able to vary that pin portion (T) embedded in the supporting layer (2) and to be able to use one and the same pin for panels having different layer thicknesses.
An infill panel of the type comprising at least one supported layer (1) and one supporting layer (2) separated by at least one insulating layer (3), characterised in that the two panels are connected together by devices in accordance with the characterising part of claims 1 to 12.
An infill panel comprising at least one supported layer (1) and one supporting layer (2) separated by at least one insulating layer (3), characterised in that the two panels are connected together by devices in accordance with the characterising part of claims 13 to 17.
A connection system for infill panels, comprising a supported outer layer (1) and a supporting inner layer (2) separated by an intermediate insulating layer (3), characterised in that the layers (1, 2, 3) are connected together by connection devices in accordance with one of claims 1 to 12 and retention devices in accordance with one of claims 13 to 17.