Fastener

Abstract

A fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion includes a first thread that begins toward the tip and extends toward the head, and wherein the engagement portion also includes a second thread that interleaves with the first thread. 20 24 20 32 81 17 M ay 2 02 4 A B S T R A C T 2 0 2 4 2 0 3 2 8 1 1 7 M a y 2 0 2 4 1 / 13 FIGURE 1 10 24 22 12 14 16 20 18 1 / 13 10 12 24 14 22 20 16 18 FIGURE 1 20 24 20 32 81 17 M ay 2 02 4 1 7 M a y 2 0 2 4 1 0 2 0 2 4 2 0 3 2 8 1 1 2 1 4 2 2 2 0 1 6 1 8

Description

TECHNICAL FIELD

[0001] The invention relates to a fastener, in particular a self-drilling fastener. The fastener is particularly, although not exclusively, suitable for use in the construction of timber structures such as roofs and decks. BACKGROUND

[0002] Self-drilling screws are the fastener of choice for many timber-based applications such as roofing and decking.

[0003] As the name implies, self-drilling screws do not require a pilot hole in order to perform as a fastener. Rather, self-drilling screws include a threaded shank that terminates in a drill-like pointed tip, the tip being designed to drive through relatively soft substrate materials including wood, soft steels and metals thus eliminating the need for a pre-drilled pilot hole.

[0004] Generally speaking, the pull-out or hold-down strength of a screw is a function of its surface area - with a denser thread pitch providing an increased surface area that engages with the material and therefore results in a higher the pull-out strength of the fastener. A drawback of a higher thread pitch, however, is the additional number of rotations required to linearly drive the fastener into the material.

[0005] When used in roofing applications, self-drilling screws require a sufficient hold-down or pull-out strength to meet wind load requirements. This typically dictates a comparatively dense thread pitch that results in an increased drive time for each fastener. Furthermore, while selfdrilling screws do not require pilot holes, increased torque demands placed on the power tool to drive the fastener into the substrate can reduce battery life of the power tool and necessitate battery changes that result in down time and further slow the speed of installation.

[0006] Another pain point that is associated with the building of timber structures such as decks is the splitting of plank ends when being fastened to a joist. Such splitting typically necessitates total replacement of the plank, which is time consuming and wasteful.

[0007] The present invention was conceived with these short-comings in mind, and seeks to at least in part alleviate the above-identified problems or to offer the public with a useful alternative. 2024203281   17 May 2024 SUMMARY

[0008] In a first aspect, the invention provides a fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion includes a first thread that begins toward the tip and extends toward the head, and wherein the engagement portion also includes a second thread that interleaves with the first thread.

[0009] The first thread and the second thread may have the same pitch. The first thread and the second thread may extend in parallel along the engagement portion. The second thread may be rotationally offset relative to the first thread. The first thread and the second thread may be of substantially equal depth. The first thread and the second thread may have a pitch of between about 5 and about 10 threads per inch.

[0010] In some embodiments, the first thread and the second thread may have a trilobular profile. The respective lobes of the first thread and the second thread of the engagement portion are offset from one another to form a serrated profile.

[0011] The second thread may begin toward the tip. Alternatively, the first and second threads may have staggered starts. The second thread may begin at least partly up the shank and away from the tip. The first thread and the second thread may terminate an equal distance from the head.

[0012] In a second aspect, the invention provides a fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion begins toward the tip and extends toward the head, and wherein the engagement portion includes at least one thread having a trilobular profile.

[0013] The engagement portion may include a second thread that interleaves with the first thread. The respective lobes of the first thread and the second thread may be offset from one another to form a serrated profile.

[0014] The shank described herein may further comprise a cutting portion disposed between the engagement portion and the head.

[0015] In a third aspect, the invention provides a fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion begins toward the tip and extends toward the head, and wherein the shank further includes a cutting portion disposed between the engagement portion and the head. 2024203281   17 May 2024

[0016] The cutting portion described herein may have a sawtooth profile. The cutting portion may include a plurality of projections that extend along the shank. The projections may wrap at least partly around the shank. The cutting portion may have a diameter that is less than that of the engagement portion. The cutting portion may comprise a plurality of spaced apart burr portions.

[0017] In some embodiments, the tip of the fastener described herein may be a pointed tip. Alternatively, the tip may be spade shaped. Alternatively, the tip may be a fluted cutting tip. The fluted cutting tip may be a triple fluted cutting tip. Alternatively, the tip may be spear shaped.

[0018] The fastener described herein may further comprise a recess that extends longitudinally along the shank from the tip and at least partly through engagement portion. Threads of the engagement portion may be broken by the recess. Alternatively or additionally, such fastener may comprise at least one groove that extends longitudinally along the engagement portion. The groove may extend along a complete length of the engagement portion. The groove may be a discontinuous groove.

[0019] In some embodiments, the head of the fastener described herein may include a plurality of ribs arranged around an undersurface thereof. The ribs may have a saw tooth profile. The ribs may be blade-like ribs that function as embedding teeth. The ribs may be step-like ribs having a height that tapers reducingly that function as counter bore teeth. The ribs may be spokelike ribs comprising substantially planar ramp surfaces that transfer applied loads away from a centre-line of the fastener. Alternatively, the ribs may be scalloped ribs that function as counterbore teeth to assist in embedding the head into the substrate. The scalloped ribs may have a flat leading edge and a curved trailing edge.

[0020] The head may include a receiving portion for a tool to rotationally drive the fastener. The head may have a countersunk profile, having a diameter that tapers reducingly to that of the shank. Alternatively, the head may be a wafer type head. The wafer type head may be substantially devoid of a countersunk detail. The wafer type head may be a soft edged head.

[0021] The fastener described herein may comprise a coating that is applied to at least a portion of the shank, the coating being a low-friction coating. The coating may be applied to the engagement portion of the shank only. The coating may be a PTFE based coating.

[0022] In a fourth aspect, the invention provides a fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the head includes a receiving portion for receiving a corresponding driving portion of a 2024203281   17 May 2024 driving tool, the receiving portion comprising a plurality of cooperating elements spaced toward a periphery of the head.

[0023] The receiving portion may comprise a plurality of notches shaped to receive complementarily shaped bosses of the driving tool. The receiving portion may comprise three notches equispaced around a circumference of the head Alternatively, the receiving portion may comprises a plurality of bosses shaped to be received within correspondingly shaped notches of the driving tool.

[0024] In a fifth aspect, the invention provides a driving tool for use with the fastener of the fourth aspect, with the driving tool having a drive portion that is complementary to the receiving portion of the fastener.

[0025] In a sixth aspect, the invention provides a kit comprising at least one fastener of the fourth aspect, and the driving tool of the fifth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: Figure 1 is an elevation view that shows a fastener in accordance with an embodiment of the invention; Figure 2 is an enlarged perspective view showing an upper portion of a shank of the fastener of Figure 1; Figure 3 is a sectional view along the line A-A of Figure 2; Figures 4 and 5 are perspective views showing a head of the fastener of Figure 1; Figure 6 is a perspective view showing a fastener in accordance with another embodiment of the invention; Figure 7 is an enlarged perspective view of a lower portion of the shank of the fastener of Figure 6; Figure 8 is a perspective view showing a fastener in accordance with another embodiment of the invention; Figure 9 is an enlarged perspective view of a lower portion of the shank of the fastener of Figure 8; 2024203281   17 May 2024 Figures 10 to 15 are enlarged perspective views showing alternative tip geometries that may be incorporated into the shank of the fastener of any one of Figures 1,6 and 8; Figures 16 to 19 are enlarged perspective views showing alternative rib geometries that may be incorporated into the head of fasteners of any one of Figures 1, 6 and 8; Figure 20 is an enlarged perspective view showing an alternative burr geometry that may be incorporated into the cutting portion of fasteners of any one of Figures 1, 6 and 8; Figures 21 and 22 are a perspective view showing an exemplary fastener having the burr geometry of Figure 20, the tip geometry of Figure 15 and the rib geometry of 19; Figure 23 is an enlarged perspective view showing a fastener head having a peripheral receiving portion in accordance with another embodiment of the invention; Figure 24 is a perspective view of a driving tool suitable for use with the fastener head of Figure 23; and Figure 25 schematically illustrates a kit comprising a plurality of fasteners and driving tools for use therewith, in accordance with another embodiment of the invention. DETAILED DESCRIPTION

[0027] In the following detailed description, reference is made to accompanying drawings which form a part of the detailed description. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings may be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are contemplated in this disclosure.

[0028] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present, a limited number of the example methods and materials are described herein.

[0029] In general terms, the fastener 10 shown in the Figures comprises a head 12 and an elongate shank 14 that extends therefrom. The shank 14 terminates in a tip 16. Afirst thread 18 begins toward the tip 16 and extends along the shank 14 toward the head 12. A second thread 20 extends along the shank 14, with the second thread 20 interleaving with the first thread 18. Together, the first and second threads 18, 20 provide an engagement portion 22 of the shank 14. 2024203281   17 May 2024

[0030] Advantageously, because the threads 18, 20 are offset and interleave with one another, the effective surface area provided by the engagement portion 22 is increased. This allows the threads 18, 20 of the fastener 10 to have a reduced or comparatively coarse pitch for a given or desired pull-out strength. For example, it is contemplated that a fastener 10 that is used for batten fastening in the assembly of a timber roof structure may only require a thread density or pitch of, for example, between 5 and 10 threads per inch, and most preferably between 7 and 8 threads per inch.

[0031] The fastener 10 is a self-drilling fastener that is designed to be rotationally driven into a soft substrate material such as timber by a hand-held powered tool (not shown) such as a drill, without the need for pre-drilling of a pilot hole or the like. Beneficially, the coarse pitch of the first and second threads 18, 20 results in greater linear advancement or distance travelled by the fastener 10 into the substrate for each rotation thereof, resulting in faster installation speed and reducing the "power on" time required of a power tool. For example, up to 50% less time may be taken to drive the fastener 10 into the substrate. It is to be understood, however, that the fastener 10 may, alternatively, be manually driven into the substrate by, for example, a screwdriver, with the coarse thread pitch serving to reduce the effort and exertion required.

[0032] An embodiment of the fastener 10 will now be described in detail with reference to Figures 1 to 5.

[0033] With reference to Figure 1, the engagement portion 22 extends from the tip 16 approximately half way up the shank 14. Specifically, each of the first thread 18 and the second thread 20 are helix shaped threads, beginning at the tip 16, wrapping around and extending along the shank 14 towards the head 12. The threads 18, 20 are co-operating threads. What is meant by this is that each thread is of substantially the same depth and pitch, extending in parallel up the shank 14 in the same rotational direction, intertwining with one another. The thread depth is at least partly a function of the material / substrate within which the fastener 10 is designed to be used. In this way, both the first and second thread 18, 20 provide engagement surfaces that engage with the substrate and contribute to the holding strength of the fastener 10. Put differently, whilst a conventional single threaded fastener includes one single helix-shaped engagement surface, the fastener 10 includes a multiplicity of interleaving helix-shaped engagement surfaces - one per each of threads 18, 20. For clarity, different colours / shading are used to distinguish between the threads 18, 20 in the Figures.

[0034] As shown, each thread 18, 20 is of the same length, extending along a complete length of the engagement portion 22. It is also contemplated, however, that either of the first thread 18 and the second thread 20 may not begin immediately proximate the tip 16, and may, 2024203281   17 May 2024 instead, begin at a point partly along the shank 14 that is spaced therefrom. Further, it is contemplated that the first and second threads 18, 20 have "staggered" starts, that is, begin at different distances along the shank 14. Likewise, whilst the illustrated embodiment shows each thread 18, 20 as being of substantially equal length and therefore terminating at a substantially equal distance from the head 12, it is also contemplated that the second thread 20 may have a length that is longer or shorter than the first thread 18.

[0035] The threads 18, 20 are symmetrically arranged around the shank 14, with a rotational offset of approximately 180 degrees. It is understood, however, that in other embodiments, the engagement portion 22 may include additional engagement threads that are equispaced around the shank 14. For example, the engagement portion 22 may have three or four co-operating threads, with each thread being of substantially the same pitch and depth and interleaving with one another. Having additional engagement threads is beneficial in that the pitch of each of the co-operating engagement threads can be reduced for a given pull-out strength - thereby resulting in a faster installation time. It is understood that in such embodiments, the offset between the respective threads will be reduced accordingly.

[0036] Whilst not shown in the Figures, it is contemplated that at least a portion of the shank 14 may be coated in a low friction coating. The coating may, for example, be a PTFE (Polytetrafluoroethylene) based coating. Preferably, the coating is applied to the engagement potion 22 of the shank only. Even more preferably, the coating is applied after the engagement portion 22 has been formed, such that a coverage of the coating extends over the engagement threads 18, 20 and the valley portions of the shank 14 located therebetween. The low friction coating serves to further reduce the drive torque required to advance the fastener 10 into the substrate. Reducing the drive torque is advantageous, because, for example, less power is drawn from a battery of a hand-held power tool for each fastener 10 installation. In this way, a greater number of fasteners 10 can be installed for a given battery charge, reducing the number of battery changes required per job. This can result in time savings for an installer who is using the fastener 10. Further, when the fastener 10 is being used in the assembly of a roof structure, reducing the torque requirements of the fastener 10 can likewise reduce the number of times that the installer is required to climb up and down a ladder to charge and / or replace a battery of the power tool -leading to increased safety. It is also contemplated that the coating may be an anti-corrosive coating leading to increased durability of the fastener 10. Corrosion protection may also be assisted by choice of material from which fastener 10 is formed. For example, in preferred embodiments, the fastener 10 is made from stainless steel 304 or stainless steel 316.

[0037] The shank 14 also includes a cutting portion 24. The cutting portion 24 is best shown in Figures 2 and 3. The cutting portion 24 is provided between the head 12 and the engagement 2024203281   17 May 2024 portion 22. The cutting portion 24 comprises a plurality of ramp-like projections or burrs 26 that project outwardly from and extend longitudinally along the shank 14. As shown, four flute-shaped projections 26 form a thread that wraps at least partly around the shank 14, in an opposite direction to threads 18, 20. It is understood, however, that the cutting portion 24 may comprise a different number of burrs 26. For example, in other embodiments, the cutting portion 24 may comprise as few as a single burr 26, whilst it is also contemplated that the cutting portion 24 may comprise six or as many as eight burrs. The number of burrs 26 may be prescribed based on the application of fastener 10 - i.e. based on intended substrate and similar factors. In addition, it is also contemplated that the projections 26 may extend substantially linearly. Further, the cutting portion 24 as a diameter that is less than that of the engagement portion 22. This is beneficial, for, in use, the engagement portion 22 is the leading portion of the fastener that is inserted into the substrate, with the cutting portion 24 then following into the hole that is formed within the substrate by the engagement portion 22. Put differently, the cutting portion 24 provides a clearance between the fastener 10 and an upper substrate, with a transition between the cutting portion 24 and the engagement portion 22 being preferably located at a junction between the substrate materials that are being joined.

[0038] The projections 26 have a cutting edge 28. The number of cutting edges 28 provided within the cutting portion 24 is a function of the number of projections 26. For example, as illustrated there are four cutting edges 28 within the cutting portion 24. In embodiments where there are six projections 26, for example, there would be six cutting edges 28 and so on. An increased number of cutting edges 28 may produce a superior clearance hole resulting in a tighter join. The cutting edge 28 is adapted such that, as the faster 10 is rotationally driven into the substrate, the cutting edge 28 cuts into the material, with the displaced material being channeled and cleared from the hole formed by the fastener 10 along the projections 26. Best shown in Figure 3, the projections 26 are arranged circumferentially around the shank 14, with the respective cutting edges 28 of each projection 26 together forming a "saw-tooth" like profile to the cutting portion 24. The saw-tooth profile of the cutting portion 24 is an important aspect of the fastener 10. This is because by cutting into and removing debris from the substrate, the sawtooth profile of the cutting portion 24 may assist in reducing the driving torque required to rotate the fastener 10 within the substrate.

[0039] The head 12 of the fastener 10 will now be described with particular reference to Figures 4 and 5. As shown in the Figures, the head 12 includes a substantially flat disc shaped upper surface 30, with a curved undersurface 32 that tapers reducingly towards the shank 14. The undersurface 32 has a countersunk profile. Specifically, the undersurface 32 has a bugle like shape that provides a smooth transition between the diameter of the upper surface of the head 12 and that of the shank 14. This shape can be advantageous when compared to more 2024203281   17 May 2024 conventional straight or linear countersink profiles as the comparatively shallow ramp angle reduces the likelihood of splitting of the substrate. In other embodiments, the head 12 may be a low profile head that sits substantially flush (or slightly proud of) the upper surface of the substrate. Further, the undersurface 32 may, in some embodiments, have a substantially linear taper or other geometries.

[0040] A plurality or ribs 34 are arranged around the undersurface 32 towards the shank 14. The ribs extend in a substantially longitudinal direction from the upper surface 30 towards the shank 14. The ribs 34 may serve to increase the structural integrity of the head 12 and / or to remove displaced material within the substrate. Furthermore, as best shown in Figure 4, each of the ribs 34 includes a cutting edge 36 that allows the head 12 to effectively drill its own hole within the substrate as the fastener is driven into the substrate, allowing the head to sit flush within the substrate and not protrude therefrom. The cutting edge 36 removes or displace material of the substrate, which would otherwise be compressed as the head 12 is driven into the substrate. In the illustrated embodiment, four ribs 34 are equispaced around a circumference of the undersurface 32, however it is understood that there could be more or less ribs 34.

[0041] Best shown in Figure 5, the upper surface 30 of the head 12 includes a receiving portion 38. As shown, the driving portion 38 is provided as a cavity 38 that extends downward into the head 12. The cavity 38 is configured to receive a driving tool. As shown in Figure 5, the cavity 38 may be shaped to accommodate and engage with a 6-point star shaped male tool, such as a Torx bit. Such driving portion 38 is particularly suited to high torque applications providing solid engagement with the driving tool. Alternatively, the cavity 38 may subsist in a 4-pointed star shape capable of receiving a Philips headed bit, or any other shape for receiving a complementary bit of the tool such that the tool is rotatably engaged therewith. It is also contemplated that in other embodiments, the receiving portion of the fastener 10 may be provided as a raised portion (as opposed to a cavity), or, alternatively, that an outer perimeter of the upper surface 30 of the head may, in itself, provide the receiving portion, being profiled, for example, to receive a spanner head therearound. It is noted, however, that such alternative embodiments are not as suitable to decking or other applications where the head 12 is required to sit flush with the substrate.

[0042] An alternative embodiment of the invention, in the form of fastener 110, will now be described with reference to Figures 6 and 7. For clarity, similar components and functional analogues will be described using similar terminology and numerical references.

[0043] Fastener 110 is similar to fastener 10, however may include an engagement portion 12 comprising a single thread 118 only. Notably, fastener 110 may be equipped with a recess 140 that extends longitudinally along the tip 116. As illustrated, the recess 140 has a V-shaped 2024203281   17 May 2024 profile that defines a cut-out or cutting edge 142. The cutting edge 142 cuts into the substrate as the fastener 10 is rotationally driven. It is understood, however, that other cutting profiles are also possible depending on the nature of the substrate for which the fastener 110 is designed to be inserted. The recess 140 may extend partly into the lower end of the shank 114. In particular, thread 118 or threads 118,120 of the engagement portion 122 are broken by the recess 140. The recess 140 has a variable depth that provides a scalloped profile, to cut and displace debris as the tip 116 drives into the substrate. Whilst not clear from the Figures, it is contemplated that the fastener 110 may include more than one recess 140, arranged equidistantly about the tip 116. In a particular example, a twin-recess arrangement may be provided. Specifically, the drilling tip 116 of the fastener 10 pierces the substrate, effectively providing a self-driven pilot hole, before the following engagement portion 122 of the shank 114 enters through the pilot hole.

[0044] Additionally, the fastener 110 may include a groove 144. In the illustrated embodiment, the groove 144 extends longitudinally along the complete length of the engagement portion 122, although it is understood that in other embodiments the groove 144 may extend only partly therealong. The groove 144 is rotationally aligned with the recess 140, such that debris that is displaced by the tip may be directed therealong. The groove 144 cuts into the threads 118, 120 of the engagement portion 122.

[0045] The groove 144 is substantially V shaped, effectively forming teeth 146 within the cut portions of threads 118, 120. The teeth 144 provide a cutting edge of the groove 144 that improves the cutting performance of the fastener 10, reducing the drive torque required. Whilst not clear from the Figures, it is contemplated that the fastener 110 may include more than one groove 144, in particular where the fastener 110 includes more than one recess 140. For example, for a fastener 110 having a twin-recess arrangement, two grooves 144 are provided, with each channel being aligned with and therefore extending longitudinally along the shank 14 from the recess 140. It is also understood that, in other embodiments, the groove 144 and recess 140 may be provided as a single continuous form that extends from the tip 116 and along the engagement portion 122. Further, the groove 144 may also be provided in the absence of the recess 140.

[0046] With particular reference to Figure 6, it is to be understood that, preferably, the respective cutting edges 136, 142 and 146 of the head 112, recess 142 and groove 144 are rotationally aligned, such that a single cutting edge extends along the fastener 110. Together, the cutting edges provide a saw-tooth like effect, with the fastener 110 operating as a serrated knife within the substrate when rotated. The alignment of the respective cutting edges is shown in the shaded area in Figure 6. For clarity, the respective cutting edges in the Figures are indicated in different colour / shading to the engagement areas of the respective threads. 2024203281   17 May 2024

[0047] It is also contemplated that the groove 144 may be a discontinuous groove. What is meant by this is that rather than forming a continuous channel along the engagement portion 122, the groove 144 may resemble plurality of spaced apart notches. For example, the groove 144 may be provided within only one of the threads 118,120. In this manner, it is possible to delineate each thread of the engagement portion 122 to allow a user to easily identify the multi-thread arrangement of the fastener 110. This may, for example, allow the user to correctly set or apply the appropriate torque levels when driving the fastener 110 into substrate - so as, for example, to avoid unexpected speeds at which the fastener 110 is driven into the substrate. It is also contemplated that each thread 118, 120 may include separate, rotationally offset discontinuous grooves to also allow visual delineation of the respective neighbouring threads 118, 120.

[0048] A further alternative embodiment of the invention, in the form of fastener 210, will now be described with reference to Figures 8 and 9. For clarity, similar components and functional analogues will be described using similar terminology and numerical references.

[0049] Fastener 210 is similar to fasteners 10 and / or 110, and may include any of the previously described features thereof. Notably, however, at least one thread of the engagement portion 222 of fastener 210 has a multi-lobular profile 246. With particular reference to the illustrated embodiment, each of the threads 218, 220 have a trilobular profile, with each engagement surface of the respective threads having three distinct lobes 248 for every rotation thereof. It is understood that other profiles including more than three lobes are also contemplated. The lobe portions 248 of the threads 218, 220 serve to increase the planar surface area of the engagement surface of the fastener 222, which can increase the hold-down I pull-out strength thereof for a given thread pitch.

[0050] It is also contemplated that, in other embodiments, only a selection of the threads of the engagement portion 222 may have a multi-lobular profile. For example, the first thread 218 may have a multi-lobular profile (for example a trilobular profile) whereas the second thread 220 may be a single lobe thread (for example a rounded thread). While in the illustrated embodiment the threads 218,220 have the same depth, it is also contemplated that the second thread 220 may have a greater or reduced depth compared to the first thread 218, depending on the substrate material that the fastener 210 is designed for.

[0051] Due to the increased surface / engagement area provided by the prominent flat lobes 248, it is also contemplated that the engagement portion 222 may include only a single thread 218, with said thread requiring a comparatively reduced pitch to provide a comparable hold-down strength of a conventional rounded or single lobe thread. 2024203281   17 May 2024

[0052] Best shown in Figure 9, the lobes 248 of the respective threads 218, 220 are offset from one another, such that the engagement portion 222 of the fastener 210 has a serrated profile 250, with each lobe 248 forming a projecting serration. For example, in the trilobular arrangement 248 shown, lobes 248 are arranged every 60 degrees around the circumference of the engagement portion 222, with the first thread 218 providing lobes 248 at, for example, 0, 120 and 240 degrees and the second thread 220 providing lobes 248 at 60, 180 and 300 degrees. Advantageously, when rotated, the serrated profile 250 of the fastener 210 operates as a knife edge that cuts through the substrate, further reducing the drive torque required. Put differently, the lobe surface 248 creates a serrated knife effect - in a radial direction, with the lobes 248 creating a high point for displacing material. ALTERNATIVE TIP GEOMETRIES

[0053] Depending on desired application, fasteners 10, 110, 210 may be provided with alternative tip geometries. Four such geometries, in the form of tips 16a to 16e are shown in Figures 10 to 15.

[0054] Seen in Figure 10, drilling tip 16a is a type-17 style tip that includes a pointed or drilling point that is provided at a distal or lower end of the shank 14 (with the opposing proximal or upper end of the shank 14 being proximate the head 12). The drilling tip 16 is configured to allow the fastener 10 to be driven into the substrate directly and without the need for a pilot hole. This enables fasteners having such tip to be rotationally driven downwards into the substrate, providing a 'self-drilling' effect. Drilling tip 16a includes a conical reduction 52 in the diameter of the shank 14 towards the distal end. This reduction aids in the speed of the initial piercing of the substrate, and reduces wandering of the tip 16a.

[0055] Turning to Figure 11 which shows an alternative self-drilling tip 16b. Spade tip 16b resembles a spade drill bit. In particular, the spade-like tip 16b includes a pair of spurs 54, which are provided at joined by a paddle-like bridge 56. The spurs 54 are angularly offset from one another - as shown the offset angle is approximately 90 degrees, providing the tip 16b with a Z shape profile. The offset between the spurs 54 assists in scooping debris from the substrate during insertion. The spade tip 16b is particularly suitable for boring comparatively large holes into wooden substrates and may create an optimal hole diameter for improved thread engagement.

[0056] Moving now to Figure 12. Fluted tip 16c resembles a twisted drill bit. In particular, fluted tip 16c includes at least one helix-like flute 58 that spirals from the distal end of the shank 14 towards the engagement portion 22. Edges of the flute provide a cutting edge as a fastener having such tip is rotatably driven into the substrate, whilst the trough thereof provides a passage 2024203281   17 May 2024 for displacement or carrying of debris from the distal end of said fastener. The fluted tip may, for example, extract an increased amount of timber debris during drive and allow for improved thread engagement.

[0057] Figure 13 shows a further variant, in the form of spear tip 16d. Spear tip 16d resembles a spearhead. In particular, the spear-like tip 16d comprises a pointed or V shaped nose 60, with a vertex thereof being particularly suitable for cleanly piercing into substrate. Scallops 62 extend axially from the nose, towards the engagement portion 22. A ridge 64 being provided therebetween the scallops 62. The scallops 62 are similar to recesses 40 described previously, providing a pathway for promoting displacement of debris from the nose 60.

[0058] Moving now to Figures 14 and 15. Multi-fluted cutting tip 16e is similar to fluted tip 16c, resembling a twisted drill bit. Notably, however, multi-fluted tip 16e includes a plurality of helix-like flutes 58 that respectively spiral from the distal end of the shank 14 towards the engagement portion 22. As shown, multi-fluted tip 16e is a triple fluted cutting tip, including three discrete troughs / flutes 58 that spiral along the engagement portion 22. Cutting edges 66 of the respective flutes 58 bite into the substrate as the fastener is rotatably driven into the substrate, whilst the trough thereof provides a passage for displacement or carrying of debris from the distal end of said fastener. The applicant has determined that three flutes is a particularly beneficial arrangement, representing a balance between driveability and debris displacement. ALTERNATIVE RIB GEOMETRIES

[0059] Depending on desired application, respective heads of fasteners 10, 110, 210 may be provided with ribs of different geometries. Three such geometries, in the form of ribs 34a to 34d are shown in Figures 16 to 19.

[0060] Beginning with Figure 16, which illustrates blade type ribs 34a. As shown, six such ribs 34a are equispaced around a circumference of the undersurface 32 of the fastener head, however it is understood that there could be more or less ribs 34. In particular, the blade-like ribs 34a function as embedding teeth to retain fastener within the substrate. Together, the respective cutting edges 36 thereof form a saw-tooth pattern or profile (cutting edges best shown by shading in Figure 4). The saw-tooth profile of the ribs 34a is an important benefit. This is because by cutting into and removing debris from the substrate, the saw-tooth profile of the ribs 34a may assist in reducing the driving torque required to rotate a fastener having such head within the substrate.

[0061] Turning now to Figure 17, which illustrates step or wafer type ribs 34b. As shown, six such ribs 34b are equispaced about and underside of the upper surface 30, extending at least 2024203281   17 May 2024 partly along the under surface 32 towards the shank 14. In particular, the ribs 34b are provided as a series of circumferentially offset steps, with each such step having a height that smoothly tapers towards the underside of the upper surface 30. In this manner, the ribs 34b serve as counter bore teeth that assist in retaining the fastener within the substrate.

[0062] Moving now to Figure 18, which illustrates spoke type ribs 34c. Six such ribs 34c project outwardly from the undersurface 32. In particular, each rib 34c comprising a substantially planar ramped surface that extends from an underside of the upper surface 30 to the shank 14. These ramped surfaces assist in radially spreading the driving loads applied to the fastener across the surface area of the upper surface 30, such that a concentration of said driving loads towards a centerline of the fastener is substantially avoided. This may, for example, allow the provision of a thinner head as the applied loads are born by the ribs 34c as opposed to the upper surface 30.

[0063] Moving now to Figure 19, which illustrates scalloped ribs 34d. As shown, six such ribs 34d project outwardly from an undersurface 32 of a wafer-type head 12. The scalloped ribs 34d have a flat leading edge (with respect to a driving direction of the fastener) and a vane-like or curved trailing edge so as to function as counter-bore teeth, which assists in embedding the wafer head 12 into the substrate. The configuration of the scalloped ribs 34d allows the wafertype head 12 to be provided with a minimal thickness - nominally only 2.5 mm as shown - such that the head 12 can be completely embedded within and sit flush with the substrate without causing cracking or splitting of the timber. ALTERNATIVE BURR GEOMETRIES

[0064] Depending on desired application, respective fasteners 10,110,210 may be provided with cutting portions 24 of different forms. For example, whilst the cutting portion 24 shown in Figures 2 and 3 and described herein comprises at least one burr-like projection 26 that extends substantially continuously along a length of said cutting portion, it is further contemplated that the cutting portion 24 may comprise a plurality of spaced apart burr portions.

[0065] With particular reference to the embodiment shown in Figure 20, cutting portion 24 comprises two spaced apart (i.e. axially offset) burr portions 26a, with each burr portion 26 comprising a plurality of ramped projections that wrap in a spiral-like manner axially along the shank 14. Trials by the applicant have determined that the linear or axial offset between the respective burr portions 26a, 26b results in an improved distribution of debris extracted from the formed hole as the respective fastener is driven into the timber substrate, with the axial spacing between the respective portions 26a, 26b providing a channel 67 for extracted debris to disperse. Preferably, the respective projections of the burr portions 26a, 26b are also rotatably offset from 2024203281   17 May 2024 one another, with the rotational offset promoting a lateral displacement of said debris via the channel. It is understood, therefore, that the provision of offset burr portions 26a, 26b together reduce the possibility in debris clogging or otherwise blocking the flutes formed between the projections, improving the overall drivability of the fastener.

[0066] Fastener 310, shown in Figures 21 and 22, provide an example of a fastener having spaced apart burr portions. In particular, fastener 310 includes a cutting portion 34 having twin spaced apart burr portions 326a, 326b and a triple fluted cutting tip 316e. Fastener 310 also includes a wafer-type head 312 having scalloped ribs 334d. Notably, the wafer-type head has soft edges and is devoid of a countersunk detail, with trials by the applicant having found that such countersunk profile may result in cracking and / or splitting of some timber substrates. ALTERNATIVE RECEIVING PORTION AND DRIVING TOOL

[0067] As previously described, each fastener 10, 110, 210, 310 is provided with a receiving portion 38 that is configured to receive and / or engage a correspondingly shaped driving portion 68 of a driving tool 70 - with said fastener being driven into a substrate via engagement of the drive portion 68 with receiving portion 38. A particularly preferred form of receiving portion 38 in the form of peripheral receiving portion 38a will now be described with reference to Figures 23 and 24. It is understood that peripheral receiving portion 38a is suitable for use with a variety of types of fasteners, and is not limited to fasteners 10, 110, 210, 310 as described herein.

[0068] Referring first to Figure 23, which illustrates peripheral receiving portion 38a. In particular, receiving portion 38a comprises a plurality of spaced apart co-operating elements 72, with said elements 72 being provided along or toward a periphery of the fastener head 12. As shown, the co-operating elements are provided in the form of three notches or crenels that are equispaced around the perimeter of the fastener head 12. This number is thought to be preferred, with the equi-spacing of said notches around the fastener head 12 having a self-centering effect during drive thereof. It is understood, however, that there may be more or less co-operating elements 72. By way of non-limiting example, there may be as few as two or as many as six cooperating elements 72. The co-operating elements 72 have a geometry that is complementary to that of drive portion 68a of a driving tool 70 for use therewith. As shown, the notches have a U or horse-shoe shape, being configured to receive a drive portion comprising complementarily shaped bosses or merlons. It is understood, however, that other shapes are also possible, such as, for example, elongate slots and triangular bites.

[0069] One such driving tool 70 is shown in Figure 24. Driving tool 70 comprises a bit that is suitable for use with conventional screw-driving power tools. The tool 70 includes a generally planar driving portion 68a that includes a plurality of upstanding elements 74 project. As shown, 2024203281   17 May 2024 tool 70 comprises three suitably arranged U or horse-shoe shaped bosses 74 that are sized and shaped to be inserted into and thus received by elements 72 of the fastener. An advantage of this drive arrangement is that applied driving forces are distributed around the perimeter of the fastener head, as opposed to being concentrated along a centerline of the fastener. This results in an increased stability when driving the fastener into hard substrate, with the driving forces being distributed across a substantially complete surface area of the fastener.

[0070] Notably, the cooperating elements 72 are provided within a footprint of the head of the fastener - i.e. the elements 72 do not extend radially beyond a perimeter of the fastener head, but rather project in a substantially axial direction of the fastener. In this way, the complementary shaped driving portion 68a of tool 70 is adapted to be arranged in coaxial abutment with the fastener, as opposed to encircling around a perimeter thereof (such as is required when driving hex head fasteners with socket type driving bits or spanners). This arrangement allows such fasteners to be removably embedded within the substrate, without the requirement of over-sized bore holes, and for the adjustment or re-tightening of such embedded fasteners. For similar reasons, this fastener / tool arrangement be particularly suitable for use in confined or accesslimited situations.

[0071] Whilst not showed in the illustrated embodiments, it is understood that the nature of the nesting of elements 72, 74 can be reversed. That is, the fastener may be provided with upstanding elements 74 and the driving tool 72 may be provided with notches 72 to receive the upstanding elements 74 therein. Such an arrangement may be less suitable for decking applications where it is desirable for the fastener head to sit flush with the timber planks. FASTENER KIT

[0072] It is contemplated that each one of the fasteners described herein may be supplied as part of a kit 76. An example of one such kit 76 is shown in Figure 25.

[0073] As shown, kit 76 includes two types of fastener and a driving tool / bit suitable for the driving thereof. It is understood, however, that the kit 76 need only include a single type of fastener, and may be supplied with or without the applicable driving tool / bit. In particular, kit 76 includes bit 70 and three fasteners 10 having a receiving portion 38a as described herein for use therewith. The kit 70 also includes a further stabilizer bit 70' with a Torx shaped drive portion and three fasteners 10' for use therewith.

[0074] With particular reference to stabilizer bit 70', it is noted that said bit is provided with a bearing portion 78', with a Torx-shaped drive portion 68' projecting therefrom. It is understood that the bearing portion 78' can also be used with tools 70 having other shaped drive portions 68. 2024203281   17 May 2024 The bearing portion 78' has an enlarged diameter that is equal to or slightly greater than that of the head of the fastener. During use, the upper face of bearing portion 78' bears against the head of fastener 10' increasing the surface area of contact therebetween, therefore improving stability and / or promoting positive alignment of the drive portion 68' with the corresponding fastener receiving portion 38.

[0075] Summarily, it is understood that the fastener as described herein provides an alternative to conventional self-drilling screw, where installation speed is restricted by a relatively dense thread pitch required to provide a desired hold-down or pull-out strength. Specifically, the fastener instead provides a multi-threaded engagement portion, with the respective threads thereof being offset from and intertwining with one another. Advantageously, this arrangement permits each of the threads to be of comparatively coarse pitch, such that the fastener advances a greater distance with each revolution thereof whilst each thread provides an engagement surface that engages with the substrate. In this respect, the fastener provides an increased install speed without effecting or otherwise sacrificing the pull-out strength of the fastener. This is particularly useful for the assembly of roof structures or deck structures, which typically require the installation of several fasteners, with the present invention resulting in significant time savings as well as reducing the battery demands on power tools used to drive the fasteners. In addition, the provision of a receiving portion at or towards a periphery of the fastener head has the effect of transferring applied driving torques across a surface area of the fastener head, reducing the concentration of loads applied along a centre-line of the fastener, thereby providing a fastener that is less likely to wander and / or fail when being driven into substrate.

[0076] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavor to which this specification relates.

[0077] Throughout this specification and the claims which follow, unless the context requires otherwise, the word ‘comprise’, and variations such as ‘comprises’ and ‘comprising’, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

[0078] While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, 2024203281   17 May 2024 the present invention should not be limited by any of the above described exemplary embodiments. 2024203281   17 May 2024 LEGEND 10 Fastener 110 Fastener 12 Head 140 Recess 14 Shank 142 Cutting edge of recess 16 Tip 144 Groove 18 First thread 146 Cutting edge of groove 20 Second thread 22 Engagement portion 210 Fastener 24 Cutting portion 246 Multi-lobular thread 26 Projections 248 Lobes 28 Cutting edge of projections 250 Serrated profile 30 Upper surface of head 32 Undersurface of head 310 Fastener 34 Ribs 36 Cutting edge of ribs 38 Receiving portion 52 Conical reduction 54 Spurs 56 Bridge 58 Flute 60 Nose 62 Scallops 64 Ridge 66 Cutting edge of tip 67 Channel 68 Driving portion 70 Driving tool 72 Notch 74 Boss 76 Kit 78 Bearing portion

Claims

1. A fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion includes a first thread that begins toward the tip and extends toward the head, and wherein the engagement portion also includes a second thread that interleaves with the first thread.

2. A fastener as claimed in claim 1, wherein the first thread and the second thread have the same pitch.

3. A fastener as claimed in any one of claims 1 or claim 2, wherein the second thread is rotationally offset relative to the first thread.

4. A fastener as claimed in any one of claims 1 to 3, wherein the first thread and the second thread are of substantially equal depth.

5. A fastener as claimed in any one of claims 1 to 4, wherein the first and second threads have staggered starts.

6. A fastener as claimed in any one of claims 1 to 5, wherein the first thread and the second thread have a tri lobular profile.

7. A fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion begins toward the tip and extends toward the head, and wherein the engagement portion includes at least one thread having a trilobular profile.

8. A fastener as claimed in claim 6 or claim 7, wherein respective lobes of the first thread and a / the second thread of the engagement portion are offset from one another to form a serrated profile.

9. A fastener as claimed in any one of claims 1 to 8, wherein the shank further comprises a cutting portion disposed between the engagement portion and the head.

10. A fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the engagement portion begins toward the tip and extends toward the head, and wherein the shank further includes a cutting portion disposed between the engagement portion and the head.

11. A fastener as claimed in claim 9 or claim 10, wherein the cutting portion has a saw tooth profile.2024203281   17 May 202412. A fastener as claimed in any one of claims 9 to 11, wherein the cutting portion includes a plurality of projections that extend along the shank.

13. A fastener as claimed in claim 9 to 12, wherein the cutting portion includes a plurality of spaced apart burr portions.

14. A fastener as claimed in any one of claims 1 to 13, further comprising a recess that extends longitudinally along the shank from the tip and at least partly through engagement portion.

15. A fastener as claimed in any one of claims 1 to 14, further comprising at least one groove that extends longitudinally along the engagement portion.

16. A fastener as claimed in any one of claims 1 to 15, wherein the head includes a plurality of ribs arranged around an undersurface thereof.

17. A fastener as claimed in claim 16, wherein the ribs have a saw tooth profile.

18. A fastener as claimed in any one of claims 1 to 17, wherein the head is a wafer-type head.

19. A fastener as claimed in any one of claims 1 to 18, wherein the tip is a fluted cutting tip.

20. A fastener as claimed in claim 19, wherein the tip is a triple fluted cutting tip.

21. A fastener comprising a head and an elongate shank that extends therefrom, the shank having a tip and an engagement portion, wherein the head includes a receiving portion for receiving a corresponding driving portion of a driving tool, the receiving portion comprising a plurality of cooperating elements spaced toward a periphery of the head.

22. The fastener as claimed in claim 21, wherein the receiving portion comprises a plurality of notches shaped to receive complementarily shaped bosses of the driving tool.

23. The fastener as claimed in claim 22, wherein the receiving portion comprises three notches equispaced around a circumference of the head.

24. A driving tool for use with the fastener of any one of claims 21 to 23, the driving tool having a drive portion that is complementary to the receiving portion of the fastener.

25. A kit comprising at least one fastener as claimed in any one of claims 21 to 23, and the driving tool of claim 24.

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