SCREW, FASTENING ARRANGEMENT, USE OF A FASTENING ARRANGEMENT, AND METHOD FOR PRODUCING A SCREW

Abstract

The invention relates to a screw (10) including a head (12), a shaft (14), and a thread (16), with the thread (16) having at least two different thread sections (18, 20), with an external diameter D.sub.Gn of a thread section (18) near the head being smaller than an external diameter D.sub.Gf of a thread section (20) distant from the head and greater than an external diameter D.sub.Sf of the shaft (14) in the area of the thread section (20) distant from the head. According to the invention it is provided that the thread (16) extends up to the bottom of the head (12). The invention further relates to a fastening arrangement (24), the use thereof, and a method.

Claims

1. A screw comprising a head, a shaft, and a thread, with the thread comprising at least first and second different thread sections, with an external diameter D.sub.Gn of the first thread section that is near the head being smaller than an external diameter D.sub.Gf of the second thread section that is distant from the head and being greater than an external diameter D.sub.Sf of the shaft in an area of the second thread section that is distant from the head, and the thread extends up to a bottom of the head.

2. The screw according to claim 1, wherein the first thread section that is near the head and the second thread section that is distant from the head have a same pitch.

3. The screw according to claim 1, wherein the external diameter D.sub.Gf of the second thread section that is distant from the head transfers continuously over a certain thread section to the external diameter D.sub.Gn of the first thread section that is near the head.

4. The screw according to claim 1, wherein the external diameter D.sub.Gf of the second thread section that is distant from the head transfers in steps to the external diameter D.sub.Gn of the first thread section that is near the head.

5. The screw according to claim 1, further comprising a drill bit.

6. A fastening arrangement comprising a screw according to claim 1, at least one flat element near the head, and a flat element distant from the head, which are connected via the screw.

7. The fastening arrangement according to claim 6, wherein a thread is inserted in the element that is distant from the head by the thread section of the screw distant from the head.

8. The fastening arrangement according to claim 6, wherein the two flat elements are held together by the head and the first thread section that is near the head, with the first thread section that is near the head applying a holding force upon the element distant from the head.

9. The fastening arrangement according to claim 6, wherein the two flat elements are held together by the head and the second thread section that is distant from the head, with the first thread section that is near the head being present in the element distant from the head in an overwound state.

10. The fastening arrangement according to claim 6, wherein the flat elements form a part of a façade substructure.

11. A method for the production of a screw according to claim 1, the method comprising: first producing a screw with the first thread section that is near the head having an external diameter as the second thread section that is distant from the head, and finishing the screw by deforming the first thread section that is near the head and this way causing a reduction of the external diameter thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The invention is now explained with reference to the attached drawings based on particularly preferred exemplary embodiments.

[0019] FIG. 1 shows a screw according to the invention;

[0020] FIG. 2 shows the screw according to the invention according to FIG. 1 for the purpose of defining diameters;

[0021] FIG. 3 shows a fastening arrangement according to the invention;

[0022] FIG. 4 shows a fastening arrangement according to the invention based on a first variant;

[0023] FIG. 5 shows a detail of FIG. 4;

[0024] FIG. 6 shows a fastening arrangement according to the invention based on a second variant; and

[0025] FIG. 7 shows a detail of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] In the following description of the drawing identical reference characters mark the same or comparable components.

[0027] FIG. 1 shows a screw 10 according to the invention. FIG. 2 shows the screw 10 according to the invention based on FIG. 1 for the purpose of defining diameters. FIG. 3 shows the fastening arrangement 24 according to the invention. The screw 10 has a head 12, which provides an engagement force, and a shaft 14. The shaft 14 carries a thread 16 which has a thread section 18 near the head and a thread section 20 distant from the head, with these two thread sections 18, 20 having different external diameters. The external diameters D.sub.Gf of the thread section 20 distant from the head is greater than the external diameter D.sub.Gn of the thread section 18 near the head. The latter is in turn greater than the external diameter D.sub.Sf of the shaft. The present screw is further equipped with a drill bit 22.

[0028] For producing a fastening arrangement 24, as shown in FIG. 3, a planar element 28 near the head having a predrilled hole is used, and further a planar element 26 distant from the head without such a predrilled hole. The screw 10 is guided through the predrilled hole of the planar element 28 near the head and it drills with its drill bit a hole into the planar element 26 distant from the head. Subsequently the thread 16 with the thread section 20 distant from the head penetrates into the element 26 distant from the head, causing an internal thread to be generated in the planar element 26 distant from the head. The feed of the screw 10 then occurs until the head 12 of the screw makes contact at the element 28 near the head. At this moment the thread section 18 near the head is already arranged in the planar element 26 distant from the head, of course only in case of an appropriate adjustment of the thickness of the planar element 28 near the head and the length of the threaded section 18 near the head. With the head 12 making contact at the planar element 28 near the head there are now two variants how to complete the fastening arrangement. This is explained in the context with the following FIGS. 4, 5, 6, and 7.

[0029] FIG. 4 shows a fastening arrangement according to the invention based on a first variant. FIG. 5 shows a detail of FIG. 4. FIG. 6 shows a fastening arrangement according to the invention based on a second variant. FIG. 7 shows a detail of FIG. 6. FIGS. 4 and 5 illustrate the status reached when the head 12 of the screw 10 has just abutted the element 26 near the head. It is further discernible that the thread section 18 near the head is located in the element 28 distant from the head, with the external thread of the screw engaging the internal thread generated by the screw. The elements 26, 28 are held together by different forces. One of the forces is the force applied by the head 12 upon the element 26 near the head. The counterforce is applied by the threaded section 18 near the head upon the element 28 distant from the head. This is perhaps supported by a force of the threaded section 20 distant from the head, which acts in the same direction. This configuration therefore achieves a tight connection of the screw 10 and the elements 26, 28. However, the screw 10 can be easily wound out of the fastening arrangement, or it may release therefrom by some external influences, because the internal thread in the part 28 distant from the head is completely intact.

[0030] The latter is different in the status illustrated in FIGS. 6 and 7. Here the screw 10 was overwound such that the internal thread is destroyed in the element 28 distant from the head. This is discernible from the fact that the material 30 of the element 28 distant from the head present in FIG. 5 is no longer present in FIG. 7. The fastening arrangement is generated in this situation by the holding force of the head 12 as well as the one of the thread section 20 distant from the head. The overwound thread in the area of the thread section near the head no longer contributes to the fastening force or only to a minor extent. However, now a protection from reverse rotation is given because the internal thread in the part 28 near the head is destroyed.

[0031] The present invention was explained using the example of two parts to be connected to each other. Of course, an arbitrary number of parts can be connected to each other if the screw is designed appropriately. Here, it is only essential that the thread section near the head in the finished fastening arrangement is located in the part showing the greatest distance from the head of the screw.

[0032] The features of the invention disclosed in the above-stated description, the drawings, as well as the claims can be essential for the implementation of the invention either individually as well as in arbitrary combinations.

LIST OF REFERENCE CHARACTERS

[0033] 10 screw [0034] 12 head [0035] 14 shaft [0036] 16 thread [0037] 18 thread section near the head [0038] 20 thread section distant from the head [0039] 22 drill bit [0040] 24 fastening arrangement [0041] 26 planar element distant from the head [0042] 28 planar element near the head [0043] 30 material