[0001] 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.
[0002] 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.
[0003] 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.
[0004] 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.
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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).
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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.
[0013] 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).
[0014] 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.
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
1. 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).
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).
3. A device as claimed in claim 2, characterised in that the head (9) has greater transverse
dimensions than the transverse dimensions of the pin.
4. A device as claimed in claim 3, characterised in that the head (9) is substantially
of T-shape.
5. 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.
6. A device as claimed in claim 2, characterised in that the guide element comprises
a rectilinear insert constructed of yieldable material.
7. 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.
8. 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).
9. 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).
10. 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).
11. 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.
12. A device as claimed in claim 1, characterised in that the pin has a substantially
cylindrical body (8).
13. 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).
14. 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.
15. 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).
16. 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).
17. 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).
18. 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).
19. 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).
20. 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.
21. 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.
22. 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.
23. 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.
24. 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.