[0001] The present invention relates to sandwich panels.
[0002] Sandwich panels have been used for a considerable time now in the building trade
and incorporate a front and rear sheet, usually formed of metal, and sandwiched between
these sheets is an insulating core which can be formed of a variety of materials such
as cellular or foam plastic, reconstituted wood, fibrous materials or the like or
a mixture of all of these.
[0003] Many different proposals have been made for joining the edges of such panels and
one such proposal is in GB-A-1072595. Here one abutting panel edge is provided with
a profiled strip, which includes two edge flanges around which are bent the ends of
the front and rear sheets respectively, and a protruding tongue portion. The interior
of the tongue portion and the space between the front and rear sheets is filled with
the insulation. The other co-operating member has both a front and rear sheet bent
first inwardly and then longitudinally parallel to the main surfaces of the sheet
material to provide free edges, the tongue of the first panel being inserted between
these free edges to provide a joint. A clamp is provided by which the assembly can
be secured to a supporting structure, the clamp engaging one of the flanges of the
profiled edge member.
[0004] While such a construction is generally satisfactory, it does have a number of problems.
Firstly, particularly if the sandwich panel arrangement is used for cladding the exterior
of a building, and to a lesser extent on internal partioning, the result of wind on
the outside of the structure can produce a suction effect. This puts the sheet metal
which projects beyond the second panel edge and engages the exterior surfaces of the
tongue under considerable loading, the sheet material not really having sufficient
strength to support any substantial loading. Secondly there is a significant reduction
in the insulating effect in the vicinity of the junction between two panels.
[0005] It is now proposed, according to the present invention, to provide a sandwich panel
comprising an insulating material core sandwiched between first and second spaced
sheets, at least one edge of the panel being closed by a connection profile in the
form of an elongate channel member of constant cross section, said cross section including
a web portion, having first and second flanges extending parallel to one another from
opposite edges to define, with the web, a channel shape, said first and second sheets
being bent around the free edges of said first and second flanges respectively, with
the opposite face of the web abutting the insulating core, a third flange extending
from said web parallel to and between said first and second flanges and spaced from
said first flange by a distance sufficiently to accommodate in said space the clamping
part of a support clamp and a tongue of an adjacent panel, the third flange being
positioned to engage an outer face of said tongue, a fourth flange extending from
said web parallel to and between said first and third flanges, said fourth flange
being positioned and shaped to co-operate with and extend into a recess formed in
the end of said tongue, so that a part of said tongue and the clamping portion of
said support clamp are between the fourth flange and the first flange when the clamping
portion of said clamp is engaged with the inner surface of said first flange to hole
said panel.
[0006] With such a construction the provision of the third and fourth flanges greatly rigidifies
the connection profile and enables the fourth flange to extend into a recess formed
in the end of the tongue of the co-operating panel. This also allows the insulating
core material to enter to immediately adjacent the end of the tongue. These provisions
both increase the rigidity of the structure and improve the insulating effect. Furthermore,
it enables one to use a sandwich panel construction which is very similar to that
already available and is shown in GB-A-1072595 with very little modification. Thus
the construction of the present invention allows one to use identical first and second
sheets, one on each face of the panel, and it enables one to maintain the same thickness
of panels and the same clamps while overcoming the problems previously mentioned.
[0007] Preferably the first, third and fourth flanges have a sufficient length to allow
for adjustable telescoping interlocking with the tongue of an adjacent panel and/or
to allow compressible sealing to be accommodated between the third and fourth flanges
this again helping to rigidify the junction and improve the insulation effect.
[0008] In a most convenient construction, the fourth flange is positioned substantially
centrally between the first and second flanges. It can therefore engage substantially
centrally in the tongue of the adjacent panel so that this tongue is equally strong
in either direction should a laterial load be put on the panels, for example, by the
wind or some other external force.
[0009] Desirably the fourth flange is tapered towards its free end to facilitate insertion
into the recess during construction of a panelling wall with the sandwich panels of
the invention.
[0010] In order to ensure that the connection profile is firmly secured to the insulating
core, to distribute the load and to rigidify the structure, at least one achoring
portion is preferably provided to project from the face of the web portion opposite
to face from which the flanges project, to be engaged by the insulating material,
which is preferably a cellular material.
[0011] In order to make up a seried of panels, preferably the edge of the panel opposite
to the one edge, which carried the connecting profile, may include a thinned down
tongue configuration with a sheet extending along each of the opposite faces of the
tongue configuration, the front edge of the tongue having an axially extending recess
formed therein, to accommodate the fourth flange of an adjacent similar panel. It
is also contemplated that any given panel could have two connection profiles on opposite
edges to co-operate with a tongue on an adjacent panel which may itself be provided
with two tongues if this is appropriate. Normally the connection profiles will be
provided on at least one side edge but it is also contemplated that they could be
provided on the top and/or bottom edge when one is building a structure which has
several panels one above the other.
[0012] The anchoring portion preferably comprises two L-section ribs extending parallel
to one another and to the flanges and having a first arm extending away from the face
of the web portion opposite to the face from which the flanges project, and a second
arm angled to said first arm, said second arms extending towards one another. This
enables a strip of rigid material to be inseeted between the arms of the anchoring
portions to join two adjacent connection profiles end to end and also improve the
anchoring of the correction profile to the insulating core.
[0013] Further to improve the seal between adjacent panels, the third flange may include
a resilient sealing lip extending from adjacent the free end of the third flange,
on the side thereof nearer said fourth flange, the free end of the sealing lip being
spaced from the web. The third flange may be provided, on its side facing the fourth
flange, with a recess in which said sealing lip can be accommodated and the face of
the sealing lip facing the fourth flange may be ribbed.
[0014] Preferably the connection profile is extruded from a relatively hard plastics material
and said sealing lip is simultaneously extruded from a relatively soft plastics material.
[0015] In order that the present invention may be more readily understood, the following
description is given, merely by way of example, reference being made to the accompanying
drawing, in which:-
Figure 1 is a cross section which shows a junction between two sandwich panesl according
to one embodiment fo the invention;
Figure 2 is a section on the line A-A of Figure 1;
Figure 3 is an end view of the connection profile of the panel of Figure 1; and
Figure 4 is a view similar to Figure 3 of a modified connection profile.
[0016] Referring first to Figure 1 there is illustrated a first sandwich panel 10 and an
adjacent second sandwich panel 11. The first panel 10 includes rear and front sheets
12, 13 of metal, eg aluminium, and which are preferably parallel. Between these is
sandwiched an insulating material 14, which may for example be cellular foam polystyrene
material, which can adhere firmly to the sheets 12,13. The insulating material is
thinned down, on the right, to provide a tongue 15, and the sheets 12, 13 continue
to cover this tongue at 16 and 17 respectively. The tongue is substantially centrally
of the thickness of the panel 10.
[0017] The second panel 11 has rear and front sheets 18 and 19 respectively sandwiching
therebetween further similar insulating material 20. The edge of the panel 11 is provided
with a connection profile indicated by the general reference numeral 21, this being
of a generally channel cross section having a web 22 and first and second flanges
23 and 24 extending generally parallel to one another and to the left, in Figure 1,
of the web 22. The profile connection 21 is secured to the insulation by anchoring
portions 25 and 26 which extend in the opposite direction from the web from the flanges
23 and 24. Free edge portions 27 and 28 of the front and rear sheets 19 and 18 are
bent around the free edges of the first and second flanges 23 and 24. A third flange
29 extends from the web portion 22 parallel and between the first and second flanges
23 and 24. The flange is spaced from the first flange by a distance sufficiently to
accommodate in the space the whole of the tongue portion 15 and the clamping part
30 of a support clamp 31 to be described further later. The third flange is then positioned
to engage the outer face of the sheet 16 defining the outer face of the tongue 15.
[0018] A fourth flange 32 extends from the web 22 parallel to, and between, the first flange
23 and the third flange 29, the fourth flange 32 being positioned and shaped to co-operate
with, and extend into a recess 33 formed in the end of the tongue 15, so that part
of the tongue and the clamping portion of the support clamp are between the fourth
flange 32 and the first flange 23 when the clamping portion 30 fo the clamp 31 is
engaged with the inner surface of the first flange to hold the panel. The panel is
in fact held by the clamp 31, which includes a bolt 33 and a nut 34, to a support
member 35 and is engaged and disengaged by turning the clamp 31 about the axid of
the bot 33 so that the clamping portion 30 can engage and disengage the flange 23.
[0019] A compressible sealing element 36 is inserted between the third and fourth flanges
29 and 32.
[0020] If reference is made to Figure 3 it will be seen that the first flange 23, the second
flange 24, the third flange 29 and the fourth flange 32 of the connection profile
21 are all substantially of the same length. The first and second profiles 23 and
24 are provided, on their inner face, with grooves 36 and 37 respectively, to receive
the free ends of the inturned portions 27, 28. The inner surface of third flange 29
is serrated at 38 to improve engagement with the sheet 16 of the tongue 15 and the
fourth flange 32 is tapered to facilitate insertion into the recess 33.
[0021] The dimensioning of the first, third and fourth flanges, particularly their length,
is adequate to allow adjustable telescoping and interlocking with the tongue 15 of
the adjacent panel and also allows the compressible sealing element 36 to be inserted
and accommodated between the third and fourth flanges.
[0022] Figure 4 illustrates a similar embodiment to that Figure 3 and like parts have been
indicated by like reference numerals with the addition of 100. It will be noted that
the two major changes involve the addition to the third flange 129 of a sealing lip
and a modification of the anchoring portions 125 an d126.
[0023] With regard to the third flange 129, this has attached to it a flexible sealing lip
140 which is formed of a relatively soft material such as a PVC having a Shore hardness
of 75. Preferably this is extruded at the same time as the remainder is extruded for
example from a rigid, high impact resistant PVC.
[0024] It will be seen that the outer face of the sealing lip 140, facing the fourth flange
132, is provided with ribs 141 and that the face of the third flange 129 facing the
fourth flange 132 is provided with a recess 142 of a sufficient size to accommodate
the sealing lip, at least partially.
[0025] It will be understood that this sealing lip provides a better seal against the tongue
15.
[0026] With regard to the anchoring portions 125, 126, these are both L-shaped having arms
125a, 126a, extending towards one another. The purpose of this is two-fold. Firstly
it provides a better anchoring with the insulating material and secondly it enables
one to insert a rigid element 150 adjacent the ends of two profiles so that the profiles
can be held together in end to end relationship. Thus one can provide a stock of standard
length profiles and these can be made up into longer profiles by use of this expedient.
1. A sandwich panel comprising an insulating material core sandwiched between first
and second spaced sheets, at least one edge of the panel being closed by a connection
profile in the form of an elongate channel member of constant cross section, said
cross section including a web portion, having first and second flanges extending parallel
to one another from opposite edges to define, with the web, a channel shape, said
first and second sheets being bent around the free edges of said first and second
flanges respectively, with the opposite face of the web abutting the insulating core,
a third flange extending from said web parallel to and between said first and second
flanges and spaced from said first flange by a distance sufficiently to accommodate
in said space the clamping part of a support clamp and a tongue of an adjacent panel,
the third flange being positioned to engage an outer face of said tongue, a fouth
flange extending from said web parallel to and between said first and third flanges,
said fourth flange being positioned and shaped to co-operate with and extend into
a recess formed in the end of said tongue, so that a part of said tongue and the clamping
portion of said support clamp are between the fourth flange and the first flange when
the clamping portion of said clamp is engaged with the inner surface of said first
flange to hold said panel.
2. A sandwich panel according to claim 1, wherein the first, third and fourth flanges
have a sufficient length to allow adjustable telescoping interlocking with the tongue
of an adjacent panel and/or to allow a compressible sealing element to be accommodated
between the third and fourth flanges.
3. A sandwich panel according to claim 1 or 2, wherein said fourth flange is positioned
substantially centrally between first and second flanges.
4. A sandwich panel according to claim 1, 2 or 3, wherein said fourth flange is tapered
towards its free edge to facilitate insertion in said recess.
5. A sandwich panel according to any preceding claim, wherein at least one achoring
portion projects from the face of said web portion opposite to said face from which
the flange projects, to be engaged by said insulating core.
6. A sandwich panel according to claim 5, wherein said at least one anchoring portion
comprises two L-section ribs extending parallel to one another and to the flanges
and having a first arm extending away from the face of the web portion opposite to
the face from which the flanges project, and a second arm angled to said first arm,
said second arms extending towards one another.
7. A sandwich panel according to any preceding claim, wherein the edge of said panel
opposite said one edge includes a thinned down tongue configuration with the sheets
extending along each of the opposite faces of the tongue configuration, the front
edge of said tongue having a generally axially extending recess formed therein, to
accommodate the fourth flange of an adjacent similar panel.
8. A sandwich panel according to any preceding claims, wherein the third flange further
comprises a resilient sealing lip extending from adjacent the free end of the third
flange, on the side thereof nearer said fourth flange, the free end of the sealing
lip being spaced from the web.
9. A sandwich panel according to claim 8, wherein the third flange is provided, on
its side facing the fourth flange, with a recess in which said sealing lip can be
accommodated.
10. A sandwich panel according to claims 8 or 9, wherein the face of the sealing lip
facing said fourth flange is ribbed.
11. A sandwich panel according to claims 8, 9 or 10, wherein said connection profile
is extruded from a relatively hard plastics material and said sealing lip is simultaneously
extruded from a relatively soft plastics material.