Facade panel screw and fastening arrangement therewith

Abstract

A facade panel screw for the optimized fastening of facade panel elements to a substructure has a head having a very large diameter, a subsequent, essentially cylindrical shaft section (22) extending along a central longitudinal axis (A) and a subsequent tip region (23). The shaft section (22) includes, as viewed from the head, a threadless underhead section (24), a stop collar (25) and a threaded section (28). The thread in a first part (26) of the threaded section (28) subsequent to the stop collar (25) has an outer diameter D.sub.r, which is attenuated compared to the thread in a second part (27) with outer diameter D.sub.n, over several convolutions, so that D.sub.r<D.sub.n. This threaded section 26 allows a controlled overwinding of the facade panel screw in use. A corresponding fastening arrangement includes a facade panel, a substructure for transferring the load to a building surface and the facade panel screw.

Claims

1. A facade panel screw (20), comprising: a head (21); a cylindrical shaft section (22) that extends along a central longitudinal axis (A); a tip region (23); the cylindrical shaft section (22), viewed from the head, comprises: a threadless underhead section (24), a stop collar (25), and a threaded section (28); a thread in a first part (26) of the threaded section (28) subsequent to the stop collar (25) has an outer diameter D.sub.r, which is attenuated over several convolutions compared to the thread in a second part (27) having an outer diameter D.sub.n, so that D.sub.r<D.sub.n.

2. The facade panel screw (20) according to claim 1, wherein the thread of the first part of threaded section (26) merges continuously into the thread of the second part of the threaded section (27).

3. The facade panel screw (20) according to claim 1, wherein a pitch in an entirety of the threaded section (28) is equally large.

4. The facade panel screw (20) according to claim 1, wherein the thread in the threaded section (28) includes multiple threads.

5. The facade panel screw (20) according to claim 1, wherein D.sub.r=a D.sub.n, and a can assume values between 0.7 and 0.9, each inclusive.

6. The facade panel screw (20) according to claim 1, wherein the attenuation is achieved by axially parallel removal of thread crests (29).

7. The facade panel screw (30) according to claim 1, wherein the stop collar (25) has a diameter D.sub.b for which applies: D.sub.b=b D.sub.n, wherein b assumes values between 1.07 and 1.24, each inclusive.

8. The facade panel screw (20) according to claim 1, wherein the stop collar (25) has an axial extent of less than 1 mm.

9. The facade panel screw (20) according to claim 1, wherein the stop collar (25), viewed radially, protrudes beyond thread crests of the thread in the second part of the threaded section (27) by less than 1 mm.

10. The facade panel screw (20) according to claim 1, wherein the tip region (23) is self-drilling, self-tapping, or a drill bit.

11. A fastening arrangement comprising: a substructure; a facade panel; and the facade panel screw (20) according to claim 1 that connects the facade panel to the substructure.

12. The fastening arrangement according to claim 11, wherein the substructure is a metal construction and at a fastening point has a material thickness of 2 to 6.5 mm of aluminum or 0.9 to 2.5 mm of steel.

13. The fastening arrangement according to claim 11, wherein the facade panel is made of plastic, metal, fiber cement, insulation materials or a composite of one or more such materials.

14. The fastening arrangement according to claim 11, wherein the underhead section (24) has an extension in an axial direction, which results as a thickness of the facade panel plus 2-4 mm.

15. The fastening arrangement (20) according to claim 11, further comprising at least one of a damping, insulating, friction-reducing or adhesive intermediate layer attached between the substructure and the facade panel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a facade panel screw according to the prior art; and

(2) FIG. 2 shows a facade panel screw according to the invention.

DETAILED DESCRIPTION

(3) FIG. 1 shows a facade panel screw 10 with its most important components. It has a large diameter head 11, the diameter of which is usually chosen so that a covering of the borehole is ensured, which is provided in the facade panel. By default, this borehole is chosen to be larger than the nominal diameter of the screw in order to give lateral clearance even in the fastened state of the facade panel. Differences in thermal expansion between the substructure and facade panel can be compensated by this. The head 11 must therefore usually be significantly oversized.

(4) The head is followed by a threadless underhead section 12 and a stop collar 13. Its effect has already been described in the “Prior Art” section above. Subsequently, seen facing away from the head toward the tip, a threaded section 14 follows, which merges into a tip 15. The thread is usually continued at least partially on the tip. There are many known designs of tips in the prior art that are shown here, shown only by way of example.

(5) FIG. 2 shows a direct comparison of a facade panel screw 20 according to the invention. It has a head 21, the dimensions of which must meet the same requirements as the design according to the prior art. An essentially cylindrical shaft 22 follows the head 21 with a subsequent or the screw final tip region 23. All three have a common, central center axis A.

(6) The shaft section 22 is comprised of a threadless underhead section 24 following the underside of the screw head 21, a stop collar 25 having a design according to the invention and a threaded section 28. This in turn is divided into a section 26 having attenuated thread 29 and a section 27 with conventional thread design. The thread in section 27 has a nominal diameter D.sub.n as shown in FIG. 2. The attenuated thread 29 has a diameter D.sub.r<D.sub.n. The stop collar 25 has a diameter D.sub.b, so that in total D.sub.b>D.sub.n>D.sub.r.

(7) The screw tip in the tip region 23 is again shown here by way of example as a self-tapping embodiment, but this is not to be understood as limiting.

(8) The features of the invention disclosed in the above description, in the drawings and in the claims can be essential for the realization of the invention both individually and in any however technically reasonable or advantageous combination. A non-explicit representation or description of a combination of features does not mean that such a combination is excluded.