SPECIFICATIONWall or roof elements composed of a foamed core and metallic covering layersThis invention relates to wall or roof elements comprising two metallic covering layers with a foamed core therebetween, where adjacent longitudinal sides of the elements have a tongued and grooved configuration for snap connection.
Such wall or roof elements have the especial advantage of easy assembly, since the snap connection enables a prealignment of the wall or roof elements to be connected together.
In one insulating panel as described in WestGerman Gebrauchsmuster DE-GM 8108886 it is considered as being worthy of improvement that the outwardly positioned seal is acted upon directly by weather conditions. Because of this, embrittlement of the seal can lead to a degradation of the sealing effect. Also, movements of the panels in the longitudinal and transverse planes due to the effects of wind and temperature lead to an opening of the sealing region and thus again to a decrease in the effectiveness of the seal.
Moreover, in the case of fire, the longitudinal connection between the parts opens up very easily and destroys the seal due to it being subjected directly to the heat. The seal is a special profile.
Usually, it has to be matched in terms of its colour to the appearance of the particular panels, without being able to utilise the optimum properties of black sealing materials which have a higher resistance to embrittlement.
It is an object of the present invention therefore to provide wall or roof elements in which the sealing action against environmental influences, and possibly also in the case of fire, is reliably maintained, and which also permits the utilisation of simple sealing materials which have the optimum effect.
This is achieved in accordance with the invention by a pair of wall or roof elements each comprising two metallic covering layers with a core of foamed material therebetween, adjacent longitudinal sides of the elements being tongued and grooved for snap connection, wherein there is provided between the said sides at most one seal arranged internally within a recess of the grooved side and interacting with a prominent longitudinal portion of the tongued side, with another recess between the sides being provided as an expansion chamber.
The wall or roof elements produce, in addition to a longitudinal connection which is characterised by a high stability, extremely favourable transmission values, especially in respect of imperviousness to air, so it is not necessary to provide two seals for use under normal circumstances.
In certain cases, with lesser demands, and particuiarly by virtue of the high continuous contact presure of the snap connection, it may even be sufficient as a sealing means for both recesses to be effective as expansion chambers.
Furthermore, it is particularly advantageous that, for all circumstances of use, the same wall or roof elements can be used, equipped with or changed over to the necessary number of seals in accordance with the particular demands.
Furthermore, the seal is protected against the direct action of environmental influences and fire, and a high degree of security is achieved against the splitting apart of the connection. A seal can be used which is simple, economical, and yet highly resistant to embrittlement, and indeed which is independent of the appearance of the particular elements themselves.
For the sealing action, it is particularly advantageous, through increased surface pressure with small impressed forces, if in accordance with a further feature of the invention the prominent longitudinal portion of the tongue side is formed as a knife-edge sealing lip.
A high stability of the lengthwise connection is achieved if the interengagement of the adjacent longitudinal sides comprises four metallic bordered tongue/groove connections.
Preferably, the longitudinal edge of one of the covering layers at the tongued side is turned back on itself through 1800 at its end to form said prominent portion, and this end overlaps the end of the covering layer of the grooved side.
Preferably, the recesses have a part-circular cross-section and are defined by the end portions of the covering layers at the grooved side, and the ends of said end portions are turned back on themselves to form hook-shaped ends.
By arranging that the element which provides the grooved side is provided with projecting lugs, the element which provides the tongued side is provided with matching retaining recesses, and the lugs and retaining recesses define a stop by their abutment, one ensures a constantly accurate assembly of the parts in a simple manner and constancy of the compression of the seal.
The snap connection is preferably formed by lugs which are substantially semi-circular in crosssection and retaining grooves which are recessed substantially at right-angles to the surface of the elements.
Simple inlaid strips can be used as the seal.
According to requirements, in one embodiment of the invention, the seal and expansion chamber, or the two expansion chambers if no seal is provided, are arranged offset relative to one another in the plane of the elements and the ends of the recesses act as holders for a common fastening sheet between the two elements.
In order that the invention may be fully understood, a number of embodiments in accordance with the invention will now be described by way of example and with reference to the drawings, in which:Fig. 1 is a cross-sectional view, on an enlarged scale, through one longitudinal connection of two wall or roof elements with one seal;Fig. 2 is a cross-section corresponding to Fig. 1 of an embodiment incorporating a fastening sheet;Fig. 3 is a cross-sectional view, on an enlarged scale, through a longitudinal connection between two wall or roof elements with two expansion chambers; and Fig. 4 is a cross-section corresponding to Fig. 3 of an embodiment incorporating a fastening sheet.
As shown in Fig. each of the wall or roof elements comprises an upper covering layer 1, a lower covering layer 2 and a central core 3 of foamed material. The longitudinal edge 4 of the lefthand element 5, which is grooved along the edge 4, and the longitudinal edge 6 of the right-hand element 7, which is tongued along the edge 6, are designed to interengage as a snap connection 8 by the interengagement of upper and lower projecting lugs 9 and retaining grooves 10.
Each of the covering layers of the left-hand grooved-edge element is turned back on itself around the respective lug 9, forming an internal web 11 extending towards a part-circular recess 12. One of these recesses 12, here the internal recess, is fitted with a seal 13. The end portion 14 of each covering layer beyond the respective recess is turned back through 180 , with the two end portions 14 held spaced apart by being embedded in a protuberance 15 of the foamed core 3. The other recess, here the outer recess 12, is left vacant to act as an expansion chamber 27.
Each of the covering layers of the right-hand tongued-edge element 7, after being turned in to define the respective retaining groove 10, forms a projecting web 16 which terminates in a knife-edge sealing lip 17 with the end 1 8 of the covering layer turned back again through 1800. The space between these ends 18 delimits a groove-like recess 19 in the foamed core 3 along the margin of the right-hand element.
The general groove in the left-hand element 5 is denoted by the reference numeral 20 and the general tongue on the right-hand element 7 is denoted by the reference numeral 21.
Along the longitudinal margins 4 and 6 of the two interengageable elements there are thus four metallic bordered tongue and groove connections; namely I from groove 20 with lugs 9/tongue 21 with retaining grooves 10; 11 from recess 10/protuberance 15; and Ill and IV from the recesses 12/sealing lips 17.
By virtue of this quadruple connection there is a high resistance to the elements splitting apart (tilting of the connected elements relative to each other) in the event of an appropriate strain, and by reducing the spacing between the end portions 14 and the sealing lips 17 one achieves a greater deformation of the seal 13 and therefore an increased sealing action.
The true ends 22 and 23 of the metallic end portions 14 and 18 respectively of the covering layers are protected by being embedded in the foamed core 3.
The lugs 9 and retaining grooves 10 abut one another, defining a "joint" 24, to facilitate their assembly.
In order to assemble the parts, the outer faces of the sealing lips 17 on each side of the tongue 21 slide along and between the lugs 9 into the groove 20. When the thickest portion of the tongue 21 has passed the position of minimum width in the entry passage, after slight elastic outward bending of the lugs 9, the lugs 9 snap into the retaining grooves 10 from their outwardly bowed positions in a resilient manner. The lugs 9 and retaining grooves 10 define the joint 24 and the inner knife-edge sealing lip 17 deforms the seal 13.
In the modified embodiment shown in Fig. 2, the seal 13 and expansion chamber 27 are arranged offset relative to each other. The end portions 14 of the covering layers inwardly of the two recesses 12 serve as holders for individual fitted securement sheets 25 which receive enclosed fastening screws which are not shown but which are indicated by the chain-dotted line 26.
In two embodiments shown in Figs. 1 and 2, the expansion chamber 27 is in each case arranged on the side which is opposite to the seal 13, for example on the outside ofthe wall or roof element.
Wind pressure acting on the external face and the effect of which is already reduced by the high contact pressure force of the outer, metallic reinforced snap connection 8, is further substantially reduced in the expansion chamber 27 and consequently, by virtue of this chamber, only a very small pressure is exerted on the seal 13. Seal 13 and inner snap connection 8 take care of the residual sealing.
Any dampness which occurs on the external face collects in the expansion chamber 27 and runs away as droplets of water, due to gravity, from the bottom of the wall or roof element.
A similar advantageous effect is achieved, when the demands on the structure are smaller, with the embodiments shown in Figs. 3 and 4, in which two expansion chambers 27 are provided, with no seal 13.
The two chambers 27 act in tandem, one behind the other.