[0001] The invention relates to a panel provided with two cover plates and with layers of
an insulating material and of a fire-retardant material located between said cover
plates.
[0002] A panel of this type is known from DE-A-4 137 241.
[0003] With this known construction layers of a fire-retardant material abut against the
inside of the cover plates, whilst a layer of insulating material is arranged between
said layers of fire-retardant material. This arrangement seems to be the only logic
arrangement, since the layers of fire-retardant material are located closest to those
surfaces that will be exposed to great heat in case of a fire.
[0004] According to the invention, however, a layer of a fire-retardant material is provided
between two layers of a thermally insulating material abutting against said cover
plates.
[0005] Surprisingly it has become apparent, that with such a construction of the panel it
is still very well possible to meet the requirements with regard to the fire-retarding
effect that are made of such panels, which are for example used for making walls in
buildings. The provision of layers of an insulating material on the outside of the
core of the panel, which is to be clad with the cover plates, thereby offers great
advantages in comparison with a construction wherein the outsides of the panel to
be clad with the cover plates are made up of layers of a fire-retardant material.
[0006] In many cases the outer surfaces of the core of the panel made up of the layers of
insulating material and fire-retardant material require machining, for example trimming
or milling, so as to give the core its correct thickness and/or to form grooves which
are to correspond with a profiled version of a cover plate.
[0007] The outer surfaces of a core can be worked much more easily when said outer surfaces
are made up of an insulating material than when said outer surfaces are made up of
a fire-retardant material, which is usually much harder than the thermally insulating
material. Furthermore, when providing the cover plates on the core it will be readily
possible to press any roughnesses still present in the insulating material or any
impurities present on the insulating slightly into the layers of insulating material,
so that an adequate smoothness and a taut outline of the cover plates can be ensured,
while retaining conventional simple methods of providing the cover plates, which is
of great importance in order to ensure an attractive appearance of the panels.
[0008] The invention will be explained in more detail hereafter with reference to the accompanying
Figure, which is a diagrammatic perspective view of a part of a panel according to
the invention.
[0009] The panel shown in Figure 1 comprises two cover plates 1 and 2 of a metal, for example
steel, which make up the outside of the panel. As is shown in the Figure, the cover
plates are profiled, in such a manner that for example parts 3 and 4 of cover plate
1 are staggered with respect to each other, in a direction perpendicularly to the
longitudinal direction of the panel. In a similar manner the cover plate 2 comprises
parts 5 and 6 which are staggered in a direction perpendicularly to the longitudinal
direction of the panel.
[0010] The longitudinal edges of the cover plates 1 and 2 are flanged in the manner shown
in the Figure, which is known per se, such that a longitudinal edge of corresponding
panels fits between the flanged parts of the cover plates 1 and 2 of another longitudinal
edge of a correspondingly shaped panel.
[0011] Two layers 7 and 8 of a thermally insulating material, generally expanded polystyrene,
are provided between the cover plates 1 and 2, whilst a layer 9 of a special fire-retardant
material is provided between said layers 7 and 8.
[0012] As already explained above, the outer layers of polystyrene can be readily machined,
inter alia with a view to forming longitudinal grooves for receiving the deflected
parts 4 and 5 of the cover plates 1 and 2. Partly because of the slightly resilient
nature of the polystyrene said cover plates 1 and 2 can thereby be glued to the layers
7 and 8 of an insulating material in such manner as to closely abut against said layers.
[0013] It is preferred to form grooves 10 and 11 extending in the longitudinal direction
of the profile in the longitudinal edges of the layer 9 of a fire-resistant material.
When assembling a wall consisting of panels of this type tongues may be inserted in
the grooves 10 and 11 of adjoining panels in order to prevent the occurrence of a
leak near the layers of fire-retardant material.
[0014] Another possibility is to coat the sides of the layers 7 - 9 with a fire-resistant
paint, which will foam at high temperatures, thus providing a seal between adjoining
panels.
[0015] Furthermore a fire-retardant putty may be provided between adjoining panels when
assembling a wall on the construction site.
1. A panel provided with two cover plates and with layers of an insulating material and
of a fire-retardant material located between said cover plates, characterized in that
a layer of a fire-retardant material is provided between two layers of a thermally
insulating material abutting against said cover plates.
2. A panel according to claim 1, characterized in that at least one of said cover plates
is profiled, seen in its longitudinal direction, in such a manner that parts of said
cover plate are staggered with respect to each other in a direction perpendicularly
to the longitudinal direction of the panel, and that said layers of a thermally insulating
material are provided with recesses for receiving parts of said cover plate.
3. A panel according to claim 1 or 2, characterized in that the longitudinal edges of
said panels are profiled in such a manner that a longitudinal edge of corresponding
panels can be inserted into ends of the cover plates of another panel projecting from
said thermally insulating material of said other panel.
4. A panel according to any one of the preceding claims, characterized in that grooves
are formed in the longitudinal edges of said layer of a fire-resistant material.
5. A panel according to any one of the preceding claims, characterized in that said cover
plates are made of a metal.
6. A panel according to any one of the preceding claims, characterized in that said insulating
material is expanded polystyrene.
7. A panel according to any one of the preceding claims, characterized in that edges
of said layers of material are coated with a fire-resistant paint.
8. An assembly comprising panels according to any one of the preceding claims, characterized
in that a fire-resistant putty is provided between adjoining panels.