Assembly having a decking

Abstract

The invention relates to an assembly having: a decking, in particular at least one board consisting of wood, wood material or plastics material; a screw having a drilling tip and a fastening thread, wherein the fastening thread extends from the drilling tip to a screw-head-side end of the fastening thread on the shank, and the screw-head-side end of the fastening thread is arranged at a first distance from an underside of a screw head; and a metal profile comprising two bearing regions for the decking, comprising at least one transverse web, which is at a second distance from the bearing regions, for the fastening thread of the screw to be screwed into, and comprising two support regions for supporting the metal profile on a ground surface or a substructure; wherein, as viewed in a screwing-in direction of the screw, a third distance from the drilling tip of the screw to the screw-head-side end of the fastening screw is shorter than or equal to the second distance from the bearing regions of the metal profile to the transverse web of the metal profile.

Description

[0001] Arrangement with a terrace covering

[0002] The invention relates to an arrangement comprising a terrace covering, in particular at least one plank made of wood, wood-based material or plastic, a screw with a drill tip and a fastening thread, wherein the fastening thread extends from the drill tip to a screw-head-side end of the fastening thread on the shaft, wherein the screw-head-side end of the fastening thread is arranged at a first distance from a bottom of a screw head, a metal profile with two support areas for the terrace covering, at least one transverse web at a second distance from the support areas for screwing in the fastening thread of the screw and two support areas for supporting the metal profile on a floor surface or a substructure.

[0003] For example, aluminum profiles can be used as the substructure for terrace construction. To ensure corrosion resistance of the finished structure, stainless steel screws are typically used. These stainless steel screws usually have a drill tip. When the stainless steel screw with the drill tip is driven through the terrace decking, the drill tip reaches the underside of the decking and, after overcoming a short gap, enters the crossbar of the metal profile. The screw's thread engages in the hole created in the decking by the drill tip. Once the drill tip makes contact with the crossbar, the screw is turned. The thread engaging with the decking then forces the drill tip forward toward the crossbar, according to the thread pitch.The resulting pressure forces on the drill bit are usually so great that the bit is destroyed. This can be remedied by pre-drilling the decking material so that the screw can be inserted through the pre-drilled hole until the drill bit touches the crossbar of the metal profile. When the screw is then turned in the pre-drilled hole in the decking material, the screw's thread does not engage with the decking material, and consequently, no forced feed occurs. The drill bit can then penetrate the crossbar of the metal profile, and the screw can be inserted into the resulting hole. Pre-drilling the decking material is time-consuming, which results in a considerable increase in time, especially when a large number of screws need to be driven into the decking. The decking material can be made of wood, engineered wood, or plastic, for example.A mixture of wood and plastic, such as so-called Wood Plastic Composite (WPC), is also considered a wood-based material. The invention aims to improve an arrangement with a terrace covering.

[0004] According to the invention, an arrangement with the features of claim 1 is provided for this purpose. Advantageous embodiments of the invention are mentioned in the dependent claims.

[0005] In an arrangement comprising a terrace covering, in particular at least one plank made of wood, wood-based material or plastic, a screw with a drill tip and a fastening thread, wherein the fastening thread extends from the drill tip to a screw-head-side end of the fastening thread on the shank, wherein the screw-head-side end of the fastening thread is arranged at a first distance from a bottom of the screw head, a metal profile with two support areas for the terrace covering, at least one transverse web at a second distance from the support areas for screwing in the fastening thread of the screw with two support areas for supporting the metal profile on a floor surface or a substructure, it is provided that, viewed in the screw-in direction of the screw,a third distance from the drill tip of the screw to the screw head end of the fastening thread is less than or equal to the second distance from the bearing areas of the metal profile to the cross web of the metal profile.

[0006] This ensures that when the drill bit is placed on the crossbar of the metal profile, the screw's fastening thread is completely outside the decking material. The screw is then driven through the decking material to such an extent that only the area between the screw-head end of the fastening thread and the underside of the screw head remains within the hole created in the decking material by the drill bit. Since the fastening thread does not engage in the hole in the decking material, it does not cause any forced feed when the drill bit is placed on the crossbar and the screw is turned. This allows the drill bit to reliably create a hole in the crossbar.The fastening thread is then screwed into the borehole created in the crossbar by means of the drill tip until an underside of the screw head rests on a top side of the terrace covering or lies in a countersink in the top side of the terrace covering.

[0007] In a further development of the invention, the shank of the screw from the screw head-side end of the fastening thread of the screw to the underside of the screw head is either smooth, with a structural thread with a smaller flank height and / or a different shape than the fastening thread or with a ribbed or grooved structure, so that after the drill tip of the screw is placed on the cross web of the metal profile, no forced feed of the screw occurs when the screw is turned.

[0008] Therefore, if the screw shank, with the section between the screw head end of the fastening thread and the underside of the screw head, is positioned in the hole created in the decking material by the drill bit, no forced feed occurs when the screw is turned. This is because the screw shank, which is either smooth, has a textured thread, or a ribbed or grooved structure, slips relative to the decking material and does not engage the wall of the hole in the decking material in such a way as to force the screw forward. The textured thread, the ribbed or grooved structure, or any other surface texture of the screw shank primarily serves to work-harden the screw shank through cold forming. The flank height of the textured thread is, in particular, only half that of the fastening thread.The structural thread can also be designed as a round thread, so that it does not engage in the decking material. In any case, the section between the screw head end of the fastening thread and the underside of the screw head must be designed such that the pull-out force of the shank section between the screw head end of the fastening thread and the underside of the screw head from the decking material is so small that no forced feed of the drill bit occurs, which could damage the drill bit during drilling. For example, the structural thread has a maximum pull-out force of 20% of that of the fastening thread in the decking material.

[0009] In a further development of the invention, the screw is made of a uniform material or different materials, in particular stainless steel.

[0010] In the arrangement according to the invention, screws made of stainless steel, whether unhardened or hardened, can be used. For example, austenitic or martensitic stainless steel can be used. The drill tip can also be made of stainless steel, in particular A2 or A4. This allows the arrangement to be used outdoors without corrosion. Within the scope of the invention, screws made of different materials can also be used, for example, with a head and shank made of stainless steel and a drill tip made of hardened carbon steel. The metal profile can, for example, be an aluminum profile.

[0011] Further features and advantages of the invention will become apparent from the claims and the following description of a preferred embodiment of the invention in conjunction with the drawings. In the drawings, Fig. 1 shows an arrangement with a terrace covering, a metal profile, and a screw according to the prior art.

[0012] Fig. 2 shows a schematic side view of an arrangement according to the invention in a first state,

[0013] Fig. 3 shows the arrangement of Fig. 3 in a second state,

[0014] Fig. 4 is a schematic representation of the arrangement of Fig. 2 from a slant above and

[0015] Fig. 5 shows the arrangement of Fig. 4 in the state corresponding to the state of Fig. 3.

[0016] Fig. 1 shows a prior art arrangement comprising a terrace covering 12, for example, a plank made of wood, wood-based material, or plastic, a screw 14 with a drill point 16, a fastening thread 18, and a screw head 20 with a drive element not visible in Fig. 1, as well as a metal profile 22. The metal profile 22 rests on a substrate 24 or a substructure with two support areas. One underside of the terrace covering 12 rests on two support areas of the metal profile 22. A transverse web 26 of the metal profile 22 provides stability to the metal profile 22 and is designed to be drilled through by the drill point 16 of the screw 14. The hole created in the transverse web 26 by the drill point 16 is then designed to allow the fastening thread 18 to be screwed into this hole, thereby anchoring the screw 14 in the transverse web 26.

[0017] As can be seen from the illustration in Fig. 1, in the depicted state where the drill bit 16 is already seated on the crossbar 26, a section of the fastening thread 18 is still located within the terrace surface 12. The borehole produced by the drill bit 16 in the terrace surface 12 has an inner diameter that is smaller than the outer diameter of the fastening thread 18. This is necessary to ensure that the borehole produced by the drill bit 16 in the crossbar 26 of the metal profile 22 also has a diameter that is smaller than the outer diameter of the fastening thread 18, so that the screw 14 with its fastening thread 18 can engage in the borehole in the crossbar 26 and thus be securely anchored to the crossbar 26.

[0018] Starting from the position shown in Fig. 1, if the screw 20 is turned clockwise, the section of the fastening thread 18 located in the terrace covering 12 causes a forced feed of the drill bit 16. This forced feed is greater than the feed with which the drill bit 16 could penetrate the transverse web 26. Consequently, considerable forces occur in the area of ​​the drill bit 16, which generally lead to the destruction of the drill bit 16 and thus to the unusability of the screw 14. Typically, the drill bit 16 is completely deformed, and the defective screw 16 must then be removed from the terrace covering 12. It is known to prevent such destruction of the screw 14 by pre-drilling the terrace covering 12.The inner diameter of the pre-drilled hole should be larger than or equal to the outer diameter of the fastening thread 18 and smaller than the outer diameter of the screw head 20. When the drill bit 16 is placed on the crossbar 26 and the screw 14 is then turned, the fastening thread 18 can slip through the pre-drilled hole or even rotate freely. The drill bit 16 can then drill a hole in the crossbar 26 as intended, namely with the feed rate determined by the drill bit. Pre-drilling the terrace surface 12 is quite labor-intensive.

[0019] Fig. 2 shows a schematic sectional view of an arrangement 30 according to the invention. The arrangement 30 according to the invention comprises the terrace covering 12, the screw 14 and a metal profile 32.

[0020] A first distance between a screw-head end of the fastening thread 18 and the underside of the screw head 20 is designated by the number A in Fig. 1. A second distance between two bearing areas 34 of the metal profile 32 for the underside of the terrace covering 12 and a transverse web 36 in the metal profile 32 is designated by the letter B. A third distance from the drill tip of the screw to the screw-head end of the fastening thread is designated by the number C in Fig. 2.

[0021] As can be seen from Fig. 2, the third distance C from the drill bit 16, specifically the free end of the drill bit 16 resting on the crossbar 36, to the screw-head end of the fastening thread 18 is smaller than the second distance B between the bearing areas of the metal profile 32 and the top of the crossbar 36. Within the scope of the invention, the distance C can also be equal to the distance B. Such a dimensioning of the third distance C and the second distance B ensures that when, as shown in Fig. 2, the drill bit 16 rests on the top of the crossbar 36, the fastening thread 18 of the screw 14 is located completely outside, or in Fig. 2 below, the terrace covering 12. If the screw 14 is inserted starting from the state shown in Fig. 2, the thread 18 of the screw 14 is located completely outside, or in Fig. 2 below, the terrace covering 12.When rotated, particularly clockwise, the drill tip 16 can create a borehole in the crossbar 36 without the fastening thread 18 in the terrace covering 12 generating a forced feed. This is because only the section of the screw shank located between the screw-head end of the fastening thread 18 and the underside of the screw head 20 is positioned in the borehole created by the drill tip 16 in the terrace covering 12.

[0022] The drill bit 16 can thus create a borehole in the crossbar 36. After creating the borehole, the fastening thread 18 can be used to form a mating thread into the borehole in the crossbar 36, in order to securely anchor the screw 14 in the crossbar 36. The screw 14 is then screwed in until the top of the screw head 20 is flush with the top surface of the terrace covering 12. The underside of the screw head 20, which may, for example, have milled pockets, can create a countersink in the top surface of the terrace covering 20 and then rest in this countersink. The screw 14 then pre-tensions the underside of the terrace covering 12 against the top surface of the support areas 34, so that the terrace covering 12 is fixed to the metal profile 32.

[0023] Fig. 3 shows this described state, in which the fastening thread 18 engages in the borehole created by the drill tip 16 in the cross web 36 and a lower side of the screw head 20 of the screw 14 lies in a countersink in the upper side of the terrace covering 12 and the terrace covering 12 is pre-tensioned against the support areas 34 of the metal profile 32 by means of the screw 14.

[0024] Fig. 4 shows a view of the arrangement 30 of Fig. 1 in the first state, which corresponds to the state of Fig. 2, from an oblique angle above.

[0025] Fig. 5 shows the arrangement 30 in a state corresponding to the state of Fig. 3, in a view from an oblique top.

[0026] In the illustrated embodiment, the screw 14 is provided with a structural thread in the area of ​​length A between the screw-head end of the fastening thread 18 and the underside of the screw head 20. This structural thread has a smaller flank height and a different shape than the fastening thread 18. The structural thread is provided on the screw shank to work-harden the screw shank by cold forming. However, the structural thread 38 is designed such that, when rotated in the borehole created in the terrace surface 12 by the drill bit 16, it does not force the drill bit 16 forward when the drill bit 16 rests on the top side of the cross rib 36 as shown in Fig. 2. Instead, the structural thread 38 slips through the borehole in the terrace surface 12.For example, extracting the structural thread from the terrace surface requires a maximum of 20% of the pull-out force needed to extract the fastening thread from the terrace surface. This prevents forced feed that could damage the drill bit. As an alternative to the structural thread 38, the shank in the section with length A can also be smooth or have a ribbed or grooved structure.

Claims

Patent claims 1. An arrangement comprising a terrace covering, in particular at least one plank made of wood, wood-based material or plastic, a screw with a drill tip and a fastening thread, wherein the fastening thread extends from the drill tip to a screw-head-side end of the fastening thread on the shank, wherein the screw-head-side end of the fastening thread is arranged at a first distance from an underside of a screw head, a metal profile with two support areas for the terrace covering, at least one transverse web at a second distance from the support areas for screwing in the fastening thread of the screw and two support areas for supporting the metal profile on a floor surface or a substructure, characterized in that, viewed in the screw-in direction of the screw,a third distance from the drill tip of the screw to the screw head end of the fastening thread is less than or equal to the second distance from the bearing areas of the metal profile to the cross web of the metal profile.

2. Arrangement according to claim 1, characterized in that the shank of the screw from the screw head-side end of the fastening thread of the screw to the underside of the screw head is either smooth, provided with a structural thread with a smaller flank height and / or a different shape than the fastening thread or with a ribbed or grooved structure, so that after the drill tip of the screw is placed on the transverse web of the metal profile, no forced feed of the screw occurs when the screw is turned.

3. Arrangement according to claim 1 or 2, characterized in that the screw is made of a single material or of different materials, in particular of stainless steel.

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