CROSS-REFERENCE TO RELATED APPLICATION
 This application claims the benefit of Netherlands patent application NL 1022956 filed Mar. 18, 2003, and U.S. provisional application 60/459,815, filed Apr. 2, 2003, and is a continuation in part of U.S. patent application Ser. No. 10/801,491, filed Mar. 16, 2004, all of which are relied on and incorporated herein by reference.
INTRODUCTION AND BACKGROUND
 The invention relates to an improved cover or cladding profile or section system for forming a variety of structures such as decking, roof and floor surfaces or siding, walls, a wall surface or a retaining wall. More particularly, the present invention relates to an improvement whereby a resilient member is placed at selected locations in the profile to avoid incorrect installation of the profiles and to enable traverse; i.e., side to side, expansion caused by initial moisture uptake of wood fibres.
 Known cover profile systems comprise elongated elements, at first only in the form of solid wooden boards, but later on also in the form of hollow or solid profiles made from other materials. Wood, wood fibre/thermoplastic composites, wood fibre/thermoset composites, synthetic material, metal, and stony materials, are examples of currently used materials.
 In an embodiment of such known systems, the boards or profiles are provided with a tongue and groove for fitting them into each other, wherein the tongue is provided with holes for passing an attachment means through, such as a nail or screw.
 Although a cover having a closed look can be obtained with the known boards or profiles, the attachment holes form a point of leakage through which water is able to penetrate the construction parts lying below or behind them or the underlying space. An example of this is a cover arranged on a wooden balcony, wherein water is able to seep down between the boards or profiles, through the balcony to the residence or parking space situated below it.
 Our earlier development described in U.S. patent application Ser. No. 10/801,491 improved on the previously known system by providing a cover profile system for forming a walking surface, roof surface, decking, siding, wall surface or wall, or the like, comprising a plurality of generally flat, elongated hollow profile bodies, or panels, each comprising a first wall, a second wall, a first longitudinal edge and a second longitudinal edge, wherein the first longitudinal edge is provided with a first longitudinal strip having holes for attachment to an underlying base, wherein the second longitudinal edge is provided with a space for accommodating an edge area of the first longitudinal strip of a matingly engaged profile body, wherein one of either longitudinal edges is provided with a second longitudinal strip, which at the side of the first strip that faces the first wall, extends over the first strip to at least at an opposite longitudinal wall of the opposite longitudinal edge. In case the profile is to be used in a horizontal position, such as for providing a tread surface, the first wall is an upper wall and the second wall is a lower wall. In case the profile is to be used in a vertical position, such as in a cladding or as a wall, the first wall is an outer wall and the second wall is an inner wall.
 As used herein, the term "generally flat" means planar profiles that would be considered as having their major dimension in one direction and, therefore, includes surfaces such as corrugated surfaces.
 As all wood composite materials will expand in the traverse direction due to moisture uptake from freshly produced wood components, it is critical that the installer keeps the required distance in between the board when installing the product. It has been observed that sometimes the installers do not correctly install the earlier described profile system of our above patent application.
 With mechanical means it often happened that the installer forced the boards or planks too close to each other for the reason that typical installation personnel are accustomed to installing normal wooden planks tight to each other as it would be expected that fresh wooden planks would shrink due to release of moisture.
 Hence, there has arisen a need for a solution to the problem of how to properly install wood-resin composites because the wood-resin composites behave just appositively from newly installed fresh wooden planks.
 Applicant has sought a way to make certain that the installation personnel always position the boards or planks in the correct distance to each other, allowing the wood-resin composite products to expand in the traverse; i.e. side to side, direction without damaging or buckling the product.
SUMMARY OF THE INVENTION
 Applicant has now improved on the system described and illustrated in the earlier U.S. patent application Ser. No. 10/801,491 filed Mar. 16, 2004 by configuring the space for accommodating the edge area of the first longitudinal strip of a matingly engaged profile body as a groove to also accommodate a resilient member. The resilient member helps to avoid incorrect installation by inexperienced workers and also makes possible traverse expansion of the adjacent profile panels to prevent damage or buckling caused by change in moisture content of the wood fibres. Further, the improved system described herein provides for the second longitudinal strip, which at the side of the first strip that faces the first wall, to extend over the first longitudinal strip into a space. Optionally, that space can also contain a resilient member. This embodiment of the invention provides for a resilient member such as a foam strip that provides expansion possibility in the width direction.
 Thus, according to the improved embodiment of the earlier invention, the same advantages from the standpoint of resistance against penetration by water are obtained. Due to the arrangement of the second longitudinal strip extending over the first strip of an adjacent profile into or in abutment against an imaginary longitudinal plane in the longitudinal wall of the adjacent profile that is perpendicular to the first and second wall, this results in covering of the first strip provided with the attachment holes. This arrangement of parts largely prevents water from entering the attachment holes so that the underlying construction space is kept free from the leakage of water. As also pointed out in the earlier application, this arrangement also prevents dirt from entering and accumulating there, which would affect the construction parts. The strip of flexible and resilient material such as foam, located in the groove space to matingly receive the first longitudinal strip, is partly compressed during and after installation to assure a snug fit between adjacent panels.
 The stiffness and dimensioning of the resilient member or strip is so chosen that this will hardly undergo a compression when the boards are installed but with the high expansion forces that may occur later will certainly do so, preventing buckling at a later stage, which may take place with conventional compositions due to lack of expansion possibilities between boards.
 As described in our earlier application, the opposite longitudinal wall is provided with a first opening for accommodating the second longitudinal strip of an adjacent profile, which further improves the shielding of the attachment holes. The first opening extends about the second longitudinal strip preferably with little play that allows an ingoing and outgoing motion. The said first opening has a space for accommodating the resilient member described herein. A relative expanding motion between both adjacent cover profiles is thus made possible after installation, in a direction traverse to the direction of the longitudinal edges, in a plane parallel to the first and second walls.
 Preferably the first opening is arranged in a first substantially raised longitudinal wall. The opening inwardly opens into a first longitudinal chamber, that may be tight fitting or widened, particularly widened in downward direction. According to an optional embodiment of the present invention, the longitudinal chamber can be filled or partially filled with the flexible and deformable material, such as foam, which is then partially compressed when the second longitudinal strip is positioned into the longitudinal chamber during installation. In this embodiment, the longitudinal chamber can be fitted with the resilient member instead of in the groove of the adjacent profile.
 In a further embodiment thereof the first longitudinal chamber is bounded by an inwardly recessed portion of the first longitudinal wall. Thus the first longitudinal wall will continue to form a unity with the first and second walls, which is advantageous to the stability and the manufacturing process.
 When the first opening ends in a first longitudinal chamber bounded by a first partition extending between the first wall and the second wall, said longitudinal chamber can be used for discharge therein of water discharged from the second longitudinal strip of an adjacent profile, when the latter is not completely tight fitting into the second opening.
 Preferably, the second longitudinal strip is formed at the second longitudinal edge, which results in a system having two longitudinal strips positioned above one another, but oriented in opposite directions, which further improves the shielding of the attachment holes.
 In a further development of the system according to the invention the space for accommodating the first longitudinal strip is formed by a second opening in the adjacent profile. The second opening is defined by a groove formed in the second longitudinal edge, which groove is bounded by groove walls. The first longitudinal strip fits into this groove and abuts the resilient member fitted into the space formed by the groove walls of the adjacent profile. The degree of penetration of the first longitudinal strip or tongue within the groove of the adjacent profile is determined by the resiliency of the resilient member contained therein. A correct positioning of the profile bodies during installation is thus facilitated.
 Preferably the second longitudinal strip extends in line with the uppermost groove wall.
 Insertion of the first longitudinal strip into the groove of an adjacent panel is enhanced when the first longitudinal strip is provided with a pilot edge at the side that faces the bottom side.
 For enhancing the discharge of intercepted water it is preferred that the first and second longitudinal edge together with the second longitudinal strip form an upwardly opening channel.
 For increasing the rigidity of the profile bodies it is furthermore preferred that between the first wall and the second wall a number of partitions are formed for defining a number of longitudinal chambers. This also improves the heat-insulation properties.
 According to the invention the first wall has a generally flat top surface which preferably is provided with an integrally formed texture. This texture can not only offer improved grip to the user's feet, but also can provide a woody look. The texture can be formed by a number of parallel oriented longitudinal grooves, for instance having a depth in the order of less than 0.5 mm to 2 mm or more. Additionally or alternatively the texture may comprise small fine longitudinal grooves, for instance having a depth in the order of 0.1 mm, and preferably being irregularly shaped and/or limited in length and/or at an acute angle to the longitudinal direction of the profile body. As is known in the art, any suitable surface texture, embossing or brushing can be applied to the profiles of this invention to give a wood grain look to the products.
 The second wall can be provided with longitudinal grooves, optionally the lower or inner side of the second longitudinal strip as well.
 Although generally flat or panel-shaped profiles are described herein as detailed embodiments of the invention, it will be apparent to those skilled in this art that the profiles or sections can have other shapes such as corner profiles.
 Preferably the profile body is formed through extrusion from a composite material of a thermoplastic polymer containing cellulose fibres. The content of cellulose fibres preferably is more than 50% by weight, more preferably at least 70% by weight, most preferably 70-80% by weight. Such composite material has the appearance of wood. In this way, the need for an add-on layer that provides a wood-like appearance afterwards, as is often done in the conventional manufacture of known synthetic siding profiles, can be dispensed with. This is particularly the case when the aforementioned texture is present on the top surface of the composites of the present invention.
 The strength and the wood-like appearance is further enhanced when the cellulose fibres comprise a quantity of relatively short, randomly oriented fibres, as well as a quantity of relatively long fibres that are oriented in profile direction, as described in applicant's U.S. Pat. No. 6,929,841 which is relied on and incorporated herein by reference, and corresponding to other products of the applicant that have been registered under the trade name TECH-WOOD.RTM..
 Preferably the short fibres have a length in the range of 0.2-2 mm and the long fibres have a length in the range of 2-8 mm, preferably 4-6 mm. The average length of the short fibres is shorter than the average length of the long fibres.
 The improved profile systems of the present invention can be used for forming a walking surface, roof surface, wall surface, wall or retaining element, or the like, and comprise a plurality of essentially flat elongated hollow profile bodies, each comprising a first wall, a second wall, a first longitudinal edge and a second longitudinal edge, wherein the first longitudinal edge is provided with a first longitudinal strip having holes for attachment to a base surface. The second longitudinal edge is provided with an opening for accommodating an edge area of a first longitudinal strip of the adjacent profile. The edge area of the first longitudinal strip is accommodated into a groove like space which contains a resilient member.
 In a further aspect, the invention provides a cover profile system for forming a walking surface, roof surface, wall surface, wall or retaining element, comprising a plurality of flat elongated hollow profile bodies, each comprising a first wall, a second wall, a first longitudinal edge and a second longitudinal edge, wherein the first longitudinal edge is provided with a first longitudinal strip serving as a tongue and the second longitudinal edge is provided with an opening serving as a groove for holding the resilient member in place and for accommodating an edge area of the first longitudinal strip of an adjacent profile. The groove is fitted with a resilient member such as foam. These profile bodies are formed through an extrusion process from a composite material of a thermoplastic polymer containing cellulose fibres. During the manufacturing process the hollow profile bodies acquire a woody look. As a result, such a system is an attractive alternative to the existing hollow aluminium and synthetic profiles.
 Although the foregoing description refers to hollow profiles, it is contemplated within this invention that profiles without a plurality of hollow chambers also come within the purview of the present invention. That is, profiles formed of a single wall suitable for example as siding are contemplated in this convention. Thus, the invention can be used for hollow and non-hollow or essentially solid products in varying thicknesses. Typical thicknesses range from 2 mm to 50 mm or more.
 In this case as well, it is preferred that the content of cellulose fibres--such as wood fibres or other cellulose containing particles--be more than 50% by weight, preferably at least 70% by weight, most preferably 70 to 80% by weight, and/or that the cellulose fibres comprise a quantity of relatively short, randomly oriented fibres, as well as a quantity of relatively long fibres that are oriented in profile direction. The short fibres have a length in the order of 0.2-2 mm and the long fibres have a length in the order of 2-8 mm, preferably 4-6 mm.
 In the formation of hollow profiles, a plurality of partitions are formed between the first wall and the second wall for defining a plurality of longitudinal chambers, as a result of which the panel or profile made of wood/synthetic composite can be lightweight and strong. In the case of single wall profiles, the profile structure is essentially solid with openings or chambers only at the ends of the profiles to facilitate mating engagement.
 In all above-described embodiments, the thermoplastic polymer used can be a polyolefin, such as polypropylene or polyethylene, or polyvinylchloride, polyamide, or other suitable polymers.
 The hollow and single wall structures of the present invention can be used to form a floor, roof or wall constructed using a cover profile system as described herein.
 Thus, in an aspect of the invention, there is provided a panel for use in a cover profile system for forming a walking surface, roof surface, wall surface, wall member, retaining wall or the like, comprising a generally flat, elongated profile body, having at least a first wall, a first longitudinal edge and a second longitudinal edge, wherein the first longitudinal edge is provided with a first longitudinal strip having at least one hole for attachment means, wherein said second longitudinal edge is provided with a space for accommodating an edge area of a first longitudinal strip of a second panel to be located in an adjacent position, said space containing a resilient member, wherein the second longitudinal edge of said panel is provided with a second longitudinal strip, which when in mating engagement with an adjacent panel, extends over a first longitudinal strip of said adjacent panel towards at least an oppositely located longitudinal wall of said adjacent panel when in mating engagement therewith.
 In another aspect, the invention provides a cover profile system, comprising a plurality of generally flat, elongated profile bodies in mating engagement with each other, each of said bodies comprising at least a first wall, a first longitudinal edge and a second longitudinal edge, wherein the first longitudinal edge is provided with a first longitudinal strip having at least one hole for attachment means, wherein said second longitudinal edge is provided with a space for accommodating an edge area of a first longitudinal strip of an adjacent profile body, said space containing a resilient member, wherein the second longitudinal edge is provided with a second longitudinal strip, which is in mating engagement with the side of the first strip of the adjacent profile body that faces the first wall and extends over the first strip towards an opposite longitudinal wall of the opposite longitudinal edge.
 In still a further aspect, the present invention provides a profile system for forming a walking surface, roof surface, wall surface, wall or retaining element comprising a plurality of generally flat elongated profile bodies, each comprising at least a first wall, a first longitudinal edge and a second longitudinal edge, wherein the first longitudinal edge is provided with a first longitudinal strip serving as a tongue and the second longitudinal edge is provided with an opening serving as a groove and containing in said groove a resilient member and for accommodating an edge area of the first longitudinal strip, wherein the profile bodies have been formed through extrusion from a composite material of a thermoplastic polymer containing cellulose fibres.
BRIEF DESCRIPTION OF THE DRAWINGS
 The present invention will be illustrated on the basis of an exemplary embodiment shown in the attached drawings, in which:
 FIG. 1 shows a symmetrical perspective view of a hollow profile part or profile member or panel according to the invention;
 FIG. 2 shows a top view of a portion of the profile part of FIG. 1;
 FIGS. 3A and 3B show details in cross-section at the location of both longitudinal edges of the profile part according to FIGS. 1 and 2 and illustrate two different locations and positions for the resilient member;
 FIG. 4 is a cross-section view and shows two profile parts according to FIG. 1, joined together and placed on a base and show the position and location of the resilient members;
 FIG. 4A shows an enlarged detailed sectional view IVA of FIG. 4;
 FIG. 5 is a cross-section view and shows two profile parts in an alternative embodiment, in joined condition and show the position and location of the resilient members;
 FIG. 5A is a cross-section view and shows an edge detail of the alternative embodiment of the profile part according to FIG. 5; and
 FIGS. 6 and 7 are cross-section views and show cross-profiles of a first and a second other embodiment, respectively, of a profile part with resilient member in the location to enable expansion according to the invention.
DETAILED DESCRIPTION OF INVENTION
 The profile part or profile member 1 is shown in FIG. 1 and further, is manufactured by an extrusion or pushtrusion process in direction S, and is formed from a composite material, comprising a matrix of synthetic thermoplastic polymer, particularly a polyolefin, preferably polypropylene, including a plurality of, for instance 70% by weight or more, preferably 70 to 80% by weight of a mixture of short wood fibres and long wood fibres, wherein the short wood fibres have a length in the range of 0.2-2 mm and the long fibres are in the range of 2-8 mm, preferably 4-6 mm. In a manner as for instance described in U.S. Pat. No. 6,929,841, the long fibres V during manufacturing have been oriented substantially in direction S, whereas the short fibres are randomly oriented. During production of the profile part 1, use is made of dried wood fibre material that contains moisture content less than 1%, preferably less than 0.5% by weight.
 In the embodiment of a hollow profile, the profile part 1 has an upper wall 2 and a lower wall 3, having a top surface 2a and a lower surface 3a, respectively. At the longitudinal wall 8, in the first longitudinal edge 4, a first longitudinal strip 11 having a tongue 13 (see FIG. 3A) has been formed, and at the opposite second longitudinal edge 5 a groove 30 for the tongue 13 has been formed, see FIG. 3B.
 Between the longitudinal edges 4 and 5 and the upper wall 2 and lower wall 3 partitions 16 have been integrally formed, thus defining longitudinal chambers 6, 6a and 6b.
 As can be seen in FIG. 2, the top surface 2a has a series of parallel grooves 20 which extend in the longitudinal direction and which have a depth of, for instance, 1 mm. The surface in between and adjacent to the parallel grooves 20 is provided with finer grooves 21, which, for instance, have a depth of 0.1 mm and provide the surface 2a with a wood grain-like look. This fine texture is also present on pendent wall member 8a that is a part of the longitudinal wall 8, (FIG. 3A) on the first longitudinal edge 4, and also on the wall member 38 and on the top surface of the second longitudinal strip 36 (see FIG. 3B) at the second longitudinal edge 5. In fact all surfaces that are visible in use are thus provided with a fine wood grain texture. Any suitable or desirable surface decoration can be formed on these surfaces. As will be apparent, the appearance of the top surface can be altered in many ways depending upon the visual and decorative effect intended.
 As can be seen in FIG. 2 and FIG. 3A, the tongue 13 of the first longitudinal strip 11 is provided with one or more continuous holes 10, intended for an attachment means such as a screw or a nail 90 (FIG. 4). The first longitudinal strip 11 is lip-shaped and buckled, having a portion 12 positioned lower and a tongue or end portion 13 that is positioned higher than portion 12 and recessed.
 In this example shown in FIG. 3A, the above-mentioned wall member 8 is not continued into the lower wall 3 but ends at a distance below the pendant wall member 8a in order to form an opening or slit 7 extending in the longitudinal direction, which opening or slit is bounded in the downwards direction by a raised edge 9 formed in the lower wall 3, at the location of the beginning of the first longitudinal strip 11. The first longitudinal strip 11 as it were protrudes from the longitudinal wall 8 formed at the first longitudinal edge 4. Longitudinal chamber 6 can be fitted to contain the resilient member 70, which permits expansion of the system when in place and prevents any tendency to buckle or catastrophically separate.
 The second longitudinal edge 5, shown in FIG. 3B, has a groove 30, which at the lower side is defined by a lowermost groove wall 31 which is in one plane with the rest of the lower wall 3, and an uppermost groove wall 32, which continues beyond the pendent wall member 38 in order to form the protruding second longitudinal strip 36. Groove 30 has positioned therein a resilient member 70 such as a foam rubber member. Hence, one or both of the resilient members 70 can be present as shown in FIGS. 3A and 3B. The resilient member 70 provides the necessary expansion possibilities in the width direction and facilitates installation in the correct position only. Thus, the system of the present invention aims to prevent installation errors that can lead to failure.
 The joining of both longitudinal edges 4 and 5 takes place, as schematically shown in FIG. 4A, by inserting the second longitudinal strip 36 of a first profile part into the slit 7 of an adjacent second profile part in the direction A. Simultaneously, the portion 13 of the second profile part is inserted into the groove 30 of the first profile part in the direction B. This inserting action continues until the end portion 13 of the second profile part meets the resilient member 70 in groove 30. The top surface 17 of the second profile's longitudinal edge again abuts the bottom surface of the groove wall 32, so that when exerting normal forces the limit is reached for joining, whereby the forming of the channel 81 having the indicated width is accomplished. The second longitudinal strip 36 as it were extends up to or in this case beyond a imaginary plane T through the location where the strip 11 begins to project from the longitudinal wall 8, which is perpendicular to the lower wall 3. As a result the area above the first longitudinal strip 11 is shielded. This shielding is enhanced because the strip 36 lies on the upper edge of raised edge 9. The top surface of the strip 36 keeps the slit open to the lower edge of pendent wall member 8a.
 In fact a double tongue and groove connection with a possibility of expanding and which is operative in two directions is provided with on the one hand the longitudinal strip 11, particularly strip portion 13, and with groove 30, and on the other hand with the second longitudinal strip 36 and with the slit 7. As can be seen in FIGS. 4 and 4A, in assembled condition, situated on, for instance, a wooden undersurface 60, there results the shielding of the space 50 situated immediately above the attachment holes 10. The attachment means 90 are shielded as a result, whereas also moisture, such as water falling in the direction D, cannot end up in said space 50 and thus in the holes 10, and therefore not on the structure 60.
 Also at the other side an expansion possibility is provided, due to accommodation of the second longitudinal strip 36 in the opening 7, wherein the lower surface of the strip 36 is slidably positioned on the upper edge of raised edge 9.
 Due to the long fibres oriented in the longitudinal direction of the profile part 1 the expansion--in particular as a result of the absorption of moisture in the fibres after the cover profiles have been exposed to the outside air for some time--per unit of length in the longitudinal direction is considerably lower (for instance twice as low) than the expansion in traverse direction. The above-discussed interconnection of the profile parts with the resilient member provides protection against unwanted deformation.
 As can be seen in the FIGS. 3A, 4 and 4A the bottom surface 3a is provided with longitudinal grooves 22.
 The panels or profile parts 1 of the FIGS. 1-4A are particularly suitable to be used as floor boards, for instance on balconies, but also on decking, siding, jetties or wooden platforms, wherein the underlying structure is shielded. The profile provides the advantage that it does not splinter, which makes its tread surface easily accessible for bare feet.
 In FIGS. 5 and 5A an alternative form of the first longitudinal edge 4 is shown, wherein the slit 7' is bounded by a continuation of wall 8', in this case horizontally inwardly turned wall member 8'a and vertically turned wall member 8'b that merges into bottom wall 3. The wall members 8a,b together with bottom wall 3 form a first longitudinal chamber 6a', which is much smaller than first longitudinal chamber 6a of the embodiment of FIG. 1. Resilient member 70 is located in groove 30. The resilient member can also be placed in the chamber.
 In the joined situation shown in FIG. 5, the second longitudinal strip 36 extends into the slit 7', wherein the lower surface lies slidably on the raised edge 9' and the end edge thereof is at a short distance from wall member 8'b. Resilient member 70 is located in the groove 30 and/or in chamber 6a'.
 In FIGS. 6 and 7 profile parts are shown in mating engagement that are particularly suitable for use as siding parts, in particular in wall surfaces, or wall panels. The panels shown in these figures could easily be formed to be solid, that is, without the cavities 106 and 206.
 The profile parts 100 and 200 are made of the same material as profile part 1. They have an upper wall 102, 202 and an inner wall 103, 203, a first longitudinal edge 104, 204 and a second longitudinal edge 105, 205, in between which longitudinal chambers 106, 206 have been defined.
 The first longitudinal edge 104, 204 is provided with a first longitudinal strip 111, 211, having raised end lip 113, 213. In the longitudinal edge 111, 211 attachment holes 110, 210 have been made for nails and screws and the like, and namely in the portions 112, 212 thereof, which however are situated at a distance above the lower surface 103A, 203A, raised by means of, for example, longitudinal legs 117, which have been provided with support surfaces 119, 219 for abutment against an undersurface.
 The second longitudinal edges 105, 205 have been provided with a short, with respect to the end lip 113, 213, broadened groove 130, 230, downwardly or inwardly bounded by groove wall 132, 232 and upwardly bounded by second longitudinal strip 136, 236. The broadened grooves 130 and 230 are fitted with resilient members 70, such as foam or rubber. In this case the first longitudinal edge 104, 204 is not provided with a slit, as is the case indeed in the embodiment of the preceding figures. Instead the outer wall 102, 202 is extended with the second longitudinal strip 136, 236, which also forms a continuation of the uppermost groove wall, and at the end is provided with a downward stop 134, 234, as a result of which a substantially sealing stop against the top surface 102a, 202a of the adjacent profile part 100, 200 is obtained.