P/00/012 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION INNOVATION PATENT Invention Title: "FLOORBOARDS FOR A FLOORING SYSTEM" The following statement is a full description of this invention, including the best method of performing it known to me: 1 TITLE: FLOORBOARDS FOR A FLOORING SYSTEM BACKGROUND OF THE INVENTION 1. Field of the Invention THIS INVENTION relates to floorboards for a flooring system. 5 The invention particularly relates, but is not limited to, floorboards for a flooring system enabling (substantially) concealed fixing of the floorboards to the supporting floor structure (eg., joists). Throughout the specification, the term "flooring system" shall be used to include flooring systems, wall systems (eg., wall cladding), ceiling 10 systems, and other building construction systems. 2. Prior Art Until fairly recently, the floorboards of flooring systems were secured to the supporting floor joists by nails, screws or other like fasteners. These systems had a number of limitations, especially when the upper 15 surfaces of the floors were to be left exposed (ie., coated with a protective finish; and not covered by carpet(s), rug(s), vinyl sheeting, ceramic- or vinyl stiles, or similar floor-coverings ). Firstly, recesses (eg., countersunk holes) needed to be provided in the upper surfaces of the floorboards to enable the heads of the 20 fasteners to at least lie flush with the upper surfaces; or, alternatively, the fasteners needed to be individually driven into the floorboards, eg., by a hammer-and-nail punch or by a nailing gun, so that the heads of the fasteners are at least flush with the upper surfaces. When it is intended that the upper surfaces of the floorboards 2 will be left exposed (and eg. covered with a protective polyurethane or like coating to provide a hard-wearing surface), to display the aesthetic features of the floorboards, it is necessary to individually fill each "hole" in the upper surfaces of the floorboards adjacent the heads of the fasteners. 5 Various floorboard systems have been produced where the floorboards have complementary interlocking profiles along respective sidewalls of the floorboards. Typically, one sidewall of each floorboard has a projection (or tongue), engageable in a complementary recess or groove in the other sidewall of a similar floorboard, when the two floorboards are 10 placed together. In some examples of these systems, the projections may be releasably lockable within the recesses or grooves, the projections typically having hook-like profiles in end view. A further type of flooring system which has been adopted uses fixing members, commonly called "biscuits", which are placed at (usually 15 regular) spacings along the floor joists and are engageable in the recesses or grooves, having parallel sides, provided along the sidewalls of the floorboards. Typically with these flooring systems, a first floorboard is laid on the floor joist; a set of biscuits are engaged with the recess or groove of the first floorboard and the biscuits are fixed to their respective floor joists; and a 20 second floorboard is placed in position, with one sidewall engaged with the first set of biscuits, and then secured along its other sidewall by a second set of the biscuits fixed to their respective floor joists. All of the existing flooring systems hereinbefore described have one or more practical limitations, eg., in the requirements for their installation.
3 However, a major limitation with all the existing flooring systems is the inability to maintain the floorboards in secure (ie., non-rattling) connection to the supporting floor joists, as the floorboards typically undergo expansion and contraction, due to differences in temperature and/or (more 5 particularly) humidity, in the building locations, where they are installed. Any flooring system which is subject to "rattling" or "drumming" of the floorboards, as the floor is traversed is unacceptable to the market place. SUMMARY OF THE PRESENT INVENTION 10 Throughout the specification, the term "biscuit" shall be hereinafter used to identify the fixing member which secures a floorboard to a supporting floor (or other) structure of the flooring system (as hereinbefore defined.) It is an object of the present invention to provide floorboards for 15 a flooring system (as hereinbefore defined) which overcomes, or ameliorates, the limitation(s) of the prior art flooring systems. It is a preferred object of the present invention to provide floorboards for a flooring system which will enable easy, but secure, fixing of the floorboards to the supporting floor structure (eg., floor joists), whilst 20 accommodating expansion or contraction of the floorboards. It is a further preferred object of the present invention to provide profiles of the grooves or recesses in the sidewalls of the floorboards complementary to the profiles of the biscuits to form a "wedging" engagement therebetween.
4 It is a still further preferred object of the present invention to provide a special profile for the side faces of the floorboards complementary to the configuration of the biscuits, which prevents retention of water within the side faces of the floorboards. 5 Other preferred objects of the present invention will become apparent from the following description. In one aspect, the present invention resides in a sidewall of a floorboard for a flooring system (as hereinbefore defined), and operable with a biscuit (as hereinbefore defined), the sidewall extending along the body of 10 the floorboard and including: at least one groove or recess bifurcating the sidewall into upper and lower sidewall portions, the or each groove or recess being defined by inwardly-convergent upper and lower groove faces, the upper and lower groove faces being respectively inclined upwardly and downwardly relative to 15 a central plane of the body; and the lower sidewall portion lying substantially parallel to, but spaced inwardly from, the upper sidewall portion. Preferably, the included angle between the upper and lower groove faces does not exceed 90 degrees; more preferably does not exceed 20 40 degrees; most preferably is in the range of 10 - 20 degrees. Preferably, the included angle between the upper and lower groove faces is less than the included angle between the upper and lower faces of the side edges of the biscuit, so that the side edges of the biscuit engage the grooves or recesses with an interference-fit. 25 Preferably, an apex interconnecting the upper and lower groove faces is of curved, ie. concave, profile to minimize the likelihood of 5 cracks generating, and being transmitted from, the apex. In a second aspect, the present invention resides in a floorboard for a flooring system (as hereinbefore defined) having at least one side wall as hereinbefore described. 5 In a third aspect, the present invention resides in a flooring system (as hereinbefore defined) including: a supporting floor structure; a plurality of the floorboards, as hereinbefore described, laid substantially parallel on the supporting floor structure; 10 a plurality of sets of biscuits, as hereinbefore described; and respective fasteners fixing the sets of biscuits to the supporting floor structure; wherein: each set of biscuits is operably engaged with the groove(s) or recess(es) in opposed sidewalls of an adjacent pair of the floorboards, to 15 securely fix the adjacent pair of floorboards to the supporting floor structure. If preferred, a sealant material, which is preferably resiliently flexible, may be provided in any gap(s) between the adjacent pairs of floorboards. BRIEF DESCRIPTION OF THE DRAWINGS 20 To enable the present invention to be fully understood, preferred embodiments will now be described, with respect to the accompanying drawings, in which: FIGS. 1 and 2 are respective, part-sectional, perspective 6 views showing steps in the installation of a flooring system incorporating floorboards in accordance with the present invention; FIGS. 3 and 4 are respective top and bottom perspective views of a biscuit suitable for use with the present invention; 5 FIGS. 5, 6, 7 and 8 are respective top plan, bottom plan, side (from either side) and end (from either end) views of the biscuit; FIG. 9 is a sectional end view of the biscuit taken on line 9-9 on FIG. 5; FIG. 10 is a sectional end view, on an enlarged scale, showing 10 the engagement of a fastener within the hole in the biscuit; and FIG. 11 is an end view of a floorboard suitable for use in the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 15 Referring to FIGS. 1 and 2, the flooring system 10 is to be installed on the spaced timber joists J of the supporting floor structure SF of a building (not shown). The flooring system 10 employs biscuits 20 provided at spaced intervals along the joists J to securely fix floor boards 60 to the joists J, and 20 thereby their support floor structure SF; where the biscuits 20 are fixed to the joists J by suitable fasteners 80. For timber joists J, the fasteners 80 may comprise nails or screws; while for metal joists J (eg., of RHS-, C- or Z-section), self-drilling screws (eg., known under the trade mark "TEK-SCREWS") may be used.
7 As will be described hereinafter in more detail, a first floor board 60 is laid over a plurality of the joists J, and one side wall of the floor board 60 is engaged by, and secured to, the joists J by a first set of the biscuits 20, each fixed to respective joists J by respective fasteners 80. 5 As shown in FIG. 2, a second similar floor board 60 is advanced towards the first set of biscuits 20, and its side wall is engaged with the first set of biscuits 20 to fix that side portion of the second floor board 60 to the joists J. A second set of the biscuits 20 is then engaged with the other 10 side wall of the second floor board 60 to fixedly secure the second floor board 60 to the joists J, and thereby the supporting floor structure SF. This procedure is repeated until the flooring system 10 has been fully laid. A biscuit 20, suitable for the flooring system 10 , will now be 15 described with reference to FIGS. 3 to 10. The biscuit 20 has a body 21, with an upper body portion 22 and a lower body portion 23, each to be hereinafter described in more detail. The body 21 is of "modified-rectangular" shape in plan view, with curved ends 24, 25; and of "modified-T" section in end view - see FIGS. 8 to 9. 20 The lower body section 23 has a substantially central block portion 26, interconnected by end walls 27, 28 by side walls 29, 30 (which have cutaway portions). It will be noted that the end walls 27, 28 extend past the side walls 29, 30, and their extremities are aligned with reinforcing ribs 31 on 8 opposite sides of the block-portion 26. The upper body portion 22 is formed integrally with the lower body portion 23 from suitable tough, resilient plastics-material (eg., PVC), which may be reinforced with suitable glass-, carbon- or like fibres to 5 increase the mechanical strength of the biscuit 20. The cavities 32, 33 in the lower body portion 23 enable the volume of plastics-material required to manufacture each biscuit 20 to be minimised, without compromising the mechanical strength, or utility, of the biscuits 20. 10 The upper body portion 22 has elongate side edges 32, 33, each with convex (or planar) upper faces 34, 35, and lower faces 36, 37, interconnected by convex noses 38, 39. Compressible flanges 36a, 37a extend downwardly from the lower faces 36, 37, respectively. They can assist in alignment of the floorboards 60 with the biscuits 20, & can be 15 compressed or expand as the adjacent floorboards expand or contract. The included angle y between the upper and lower faces 34, 36 and 35, 37 of the side edges 32, 33 is preferably in the range 10* to 40; more preferably in the range 15* to 20*. The upper faces 34, 35 of the side edges 32, 33 are 20 interconnected by a top face 40, which extends along the body 21 of the biscuit 20. As shown in more detail in FIGS. 9 and 10, a hole 41 extends through the upper body portion 22, and centrally through the block portion 26 of the lower body portion 23. The side wall 42 of the hole 41 is 9 downwardly divergent to the bottom face 26a of the block-portion 26, and at its upper end, is in communication with an annular recess 43 in the upper body portion 22; the annular recess being terminated, at its inner end, by a "convex" frusto-conical abutment face 44. 5 The skilled addressee will appreciate that, when the fastener 80 is driven through the hole 41 (and annular recess 43) in the body 21 of the biscuit 20, the fastener 80 can be driven with its shank 81 "skewed" to the axis of the hole 41, ie., to assist in the insertion of the fastener 80 - see FIG. 1 - while the head 82 of the fastener 80 may engage, and compress, 10 the abutment face 44 to provide sealing engagement between the abutment face 44 and the head 82 of the fastener 80. FIG. 11 illustrates an end profile of a floor board 60 suitable for use with the biscuits 20 to produce the floor system 10. The floor boards 60 are preferably machined of lengths of 15 suitable timbers and may be reduced to different lengths L, widths W and/or thicknesses T to suit the particular intended application for the flooring system 10. As the dimensions of the biscuits 20 will determine the location of the longitudinal grooves in the side walls of the floor boards 60, to be 20 hereinafter described, the overall thickness T of the floor boards 60 will be varied by increasing the thickness t 1 of the upper portion of the floor boards 60 above the elongate grooves, whilst maintaining the thickness t 2 of the lower portion of the floor boards 60 substantially constant. In this embodiment, the floor board 60 has a body 61 with 10 planar top and bottom faces 62, 63, where the bottom face 63 engages, and is supported by, the spaced joists J of the supporting floor structure SF. It will be readily apparent to the skilled addressee that when the flooring system 10 has been installed, floor coverings (eg., carpets, vinyl 5 sheeting, or tiles) may be laid over the top surfaces 62 of the floor boards 60; or suitable coating(s) or paint(s) be applied thereto. For example, 2-pak polyurethane or other resinous-type coatings may be applied to the top surfaces 62 (either before or after installation) to enable the grain of the timber of the floor boards 60 aesthetically displayed, 10 The respective side walls 64 of the floor boards 60 are "mirror images," and an elongate groove 65 bifurcates each side wall 64 into upper and lower side wall portions 66, 67, where the lower side wall portion 67 is provided substantially parallel to, but spaced inwardly from, the upper side wall portion 66 by a distance X. 15 The elongate groove 65 has upper and lower groove faces 68, 69 terminating at a curved (concave) apex 70 (which may have spaced centres of curvature). The respective included angles a and p between the upper and lower groove faces 68, 69 and the central plane through the body 61 of 20 the floor board 60 are preferably equal, but may be different; and preferably the sum of the included angles, ie. (a + p), is in the range 10* to 400, more preferably 150 to 200, most preferably 200 (Preferably the sum of the included angles (a + P) is less than the included angle y between the upper and lower faces 34, 36 and 35, 37 of the side edges 32, 33 of the biscuit 20, so that the 11 side edges 32, 33 will engage the grooves 65 with an "interference-fit". It will be readily apparent to the skilled addressee that the specific profiles of the side walls 64 of the floor boards 60 will be varied to suit the particular intended application of the flooring system 10; and the final 5 profile will be dependent, inter alia, on the actual values of the upper and lower side wall thicknesses t 1 , t 2 ; the distance X by which the lower side wall portion 67 is inset relative to the upper side wall portion 66; and / or the angles a and P of the upper and lower groove faces 68, 69. By way of illustration only, the lower side wall thickness t 2 may 10 be in the range 4-7 mm; and the inset distance X may be in the range 3 5mm. The downward inclination of the lower groove faces 69 prevents retention of water in the grooves 65, promoting the life-span of the floorboards 60. 15 As illustrated in FIG. 2, the upper side wall portions 66 may be provided with a "chamfer" 71 or a convex curve (or "bull-nose") profile 72. It will also be readily apparent to the skilled addressee that the overall configuration of the biscuits 20 may also be varied by way of variations to, inter alia, the relative height of the lower body portion 23; the 20 length of the body 21 of the biscuit 20; whether or not the end walls 24, 25 are curved, concave, planar or convex; the width of the upper and lower faces 34, 35 and 36, 37 of the side edges 32, 33; the profiles of the noses 38, 39 and/or the included angle y between the upper and lower faces 34, 36 and 35, 37 of the side edges 32, 33.
12 In the embodiment illustrated, a single hole 41 (and annular recess 43) has been provided to enable the fixing of the biscuits 20 by single fasteners 80 to the floor joists J of the supporting floor structure FS. It will be readily apparent to the skilled addressee that the biscuits 20 may be 5 modified, eg., when used to fix the floor board 60 as "wall cladding" to a supporting wall, where the biscuits 20 are of increased length and have two or more holes 41 to enable the biscuits 20 to be fixed to the supporting wall by a plurality of the fasteners 80. The skilled addressee will appreciate that the present invention 10 provides a flooring system 10 (as hereinbefore defined) which enables a simple, efficient and effective method of construction; and it provides complementary biscuits 20 and floor boards 60 which can be easily and economically produced; and where the resultant wall system 10 is both strong and can have high aesthetic appeal. 15 If preferred, a sealant may be provided along the joints between the adjacent floor boards 60 to form a flexible, continuous, surface therebetween. The end walls 27 and projections or reinforcing ribs 31 on the lower body portions 23 of the biscuits 20 can absorb, eg., 1-2mm of 20 expansion or contraction of the floor boards 60 due to changes in, eg., ambient temperature and/or humidity where the wall system 10 is installed; and the "wedging" engagement between the side edges 32, 33 of the biscuits 20 with the corresponding grooves 65 of the side walls 64 of the floor boards 60 will ensure that the floor boards 60are always maintained in secure fixed 13 engagement with the joists J of the supporting floor system FS throughout the expansion/contraction range of the floor boards 60. It will also be readily apparent to the skilled addressee that, in certain applications, the floor boards 60 may be moulded, cast or extruded 5 from plastics- or metal-materials, eg., aluminium; or may be laminated or otherwise assembled from a combination of materials; where the top faces 62 have, eg., decorative finish(es) applied thereto, but where the side walls 64 are provided with profiles equal, or similar, to the profiles for the side walls 64 hereinbefore described. 10 Various changes and modifications may be made to the embodiments described and illustrated without departing from the present invention.