Fastener with protective cap

Abstract

The invention relates to a fastening element (1) with a protective cap (2). The protective cap (2) has an end face (5) and an opening (3) opposite the end face (5), in particular a cylindrical opening, for an external threaded section (4) of the fastening element (1). To enable the protective cap (2) to be easily detached from the fastening element (1), one or more predetermined breaking points (6) are arranged on the protective cap (2).

Description

[0001] The invention relates to a fastening element with a protective cap having the features of the preamble of claim 1.

[0002] A protective cap with an end face and an opposite opening for a threaded pipe is described in US4425945 A. The protective cap has a lining with an elastic material that adapts to the shape of the component to be protected in order to create a threaded engagement of the protective cap with the threaded pipe.

[0003] Patent DE 199 13 164 C1 discloses a cylindrical protective cap with one end and an opposite opening. This cap is screwed onto a threaded rod, thereby cutting a thread into the cap. To simplify installation on the threaded rod, the wall thickness at the lower end of the protective cap is slightly thinner.

[0004] US7487801 B2 describes a protective cap with a front end and an opposite opening that is clamped onto a tube or rod. A round projection extends inward on the front end, creating a hollow dome between the front end of the component to be protected and the protective cap. To facilitate assembly and disassembly, the protective cap is self-venting. This is achieved by an internal geometry with a circumferential rib for clamping onto the tube or rod, with at least one gas venting groove running in the side wall.

[0005] The object of the invention is to propose a fastening element with a protective cap that is easy to manufacture and can be easily removed from the fastening element.

[0006] This object is achieved according to the invention by the features of claim 1. The fastening element according to the invention has an external thread section which extends at one end of the fastening element along a longitudinal axis of the fastening element. The fastening element can be, for example, a threaded rod, a concrete screw, a drop-in anchor, a chemical anchor or a bolt anchor. The protective cap has an end face and an opening opposite the end face. The opening is arranged on the outside of the external thread section of the fastening element. The protective cap is held on the external thread section in particular by clamping and / or by a screw connection. The protective cap is preferably cylindrical, with a plate-shaped end face. A further preferred embodiment is a polygonal base area of ​​the end face, for example a hexagonal base area.The protective cap is easy to manufacture because it does not require complex geometries.

[0007] For better understanding, the protective cap is not considered as part of the fastening element, but as a separate element.

[0008] According to the invention, one or more predetermined breaking points are arranged on the circumference and / or the end face of the protective cap. At a predetermined breaking point, the strength of the protective cap is deliberately weakened such that a crack occurs at the predetermined breaking point upon tensile or peeling stress. As a result, the clamping and / or screwing of the protective cap on the external thread section is no longer maintained or at least weakened, and the protective cap can be removed from the fastening element without great effort.

[0009] The one or more predetermined breaking points can, for example, extend parallel to the longitudinal axis over the outer circumference and / or orthogonal to the longitudinal axis over the end face.

[0010] A preferred embodiment of the invention provides for one or more predetermined breaking points to be formed by reducing the wall thickness and / or by creating a perforation in the protective cap. In particular, the at least one predetermined breaking point is a groove in the outer surface of the protective cap. Another possible embodiment is, for example, by creating perforations in the protective cap in a line.

[0011] Another embodiment of the invention provides for a gripping means to be arranged on a portion of the circumference of the protective cap. The gripping means is, for example, an extension on a side wall of the protective cap, which a user can grasp to easily remove the protective cap from the fastening element. In particular, the gripping means is designed as a tab.

[0012] A further embodiment of the invention provides that the gripping means extends in a direction away from the end face of the protective cap. The gripping means essentially extends parallel to a central axis of the fastening element, for example, along an outer contour of the external thread section. As a result, the fastening element with the protective cap does not become longer, as would be the case with an opposite extension, and is easy to handle.

[0013] The invention particularly proposes that the gripping means be adjacent to one or more predetermined breaking points. The gripping means is preferably a tab, at the transition of which to a part that is clamped and / or screwed to the external thread section, one or more predetermined breaking points are arranged. The one or more predetermined breaking points are arranged parallel to a tab's longitudinal axis, so that when tensile stress is applied to the tab orthogonally to the longitudinal axis of the external thread section, a particularly high load acts on the part of the protective cap provided with predetermined breaking points, causing it to easily tear.

[0014] In a preferred embodiment of the fastening element with a protective cap, the protective cap is made of a plastic, for example, polyamide, polyester, polyethylene, polypropylene, or polystyrene. The use of plastic makes the protective cap lightweight, resistant to external influences, and easy to manufacture, for example, by injection molding.

[0015] The features and combinations of features, embodiments and configurations of the invention mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or drawn in a figure can be used not only in the respective combination specified or drawn, but also in principle any other combinations or individually. Embodiments of the invention are possible which do not have all the features of a dependent claim. Individual features of a claim can also be replaced by other disclosed features or combinations of features. Embodiments of the invention which do not have all the features of an embodiment, but which have in principle any part of the characterized features of an embodiment, optionally in combination with one, several or all of the features of the further embodiment, are possible.

[0016] The invention is described below using three exemplary embodiments.

[0017] They show: Fig. 1 a perspective partial view of a first fastening element according to the invention with a protective cap; Fig. 2 a second protective cap according to the invention with fastening element in a partial side view; and Fig. 3 a third embodiment of a protective cap according to the invention in perspective view.

[0018] In Fig. 1 shows a rear section of a fastening element 1 according to the invention with a protective cap 2. The fastening element 1 is, for example, a bolt anchor or a composite anchor and extends along a central axis 9. The rear section of the fastening element 1 comprises an external thread section 4. The protective cap 2 comprises an end face 5 and a cylindrical opening 3 on an opening side 31, into which the external thread section 4 of the fastening element 1 is inserted, whereby the external thread section 4 is protected from external influences. In order to create a defined crack when the protective cap is subjected to a normal force orthogonal to the central axis 9 or a peeling stress, a predetermined breaking point 6 in the form of a linear groove 10 is arranged on the circumference of the protective cap 7.On the opening side 31, a gripping means 8 extends from the cylindrical opening 3 in the direction away from the end face 5, parallel to the central axis 9 of the fastening element along the external thread section 4. The gripping means 8 can be easily gripped to apply the required normal force and, at the same time, does not protrude from the fastening element, making the fastening element 1 with the protective cap 2 easy to handle and compact.

[0019] The Fig. 2 shows an alternative embodiment of the protective cap 2 on the fastening element 1. Here, the protective cap 2 is screwed onto the external thread section 4 of the fastening element 1. Instead of the linear groove, the predetermined breaking point 6 in this embodiment is formed by rectangular openings 11 on the circumference 7 of the protective cap 2, which run in a line from the opening side 31 to the end face 5. When a peeling stress is applied, the small webs between the rectangular openings 11 break open. This releases the threaded engagement and the protective cap 2 can be easily removed from the fastening element 1. The second embodiment does not have a gripping means, although such a means could be provided.

[0020] At the Fig.In the third embodiment of the protective cap 2 without the fastening element shown in Figure 3, the predetermined breaking points 6 are formed by two spirally circumferential grooves 12 around the outside of the protective cap 2. In this embodiment, the gripping means 8 is not arranged on the opening side 31 of the protective cap 2, but rather on a circumferential section between the circumferential grooves 12 tangential to the circumference 7 of the protective cap 2. When the user pulls on the gripping means 8, the predetermined breaking point 6 breaks open, and the resulting spiral-shaped sections of the protective cap 2 can be removed from the fastening element 1. List of reference symbols 1 fastening element 2 protective caps 3 Opening 4 external thread section 5 Front side 6 Predetermined breaking point 7 Circumference of the protective cap 8 gripping devices 9 Center axis of the fastener 10 linear groove 11 rectangular openings 12 circumferential groove 31 Opening side QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 4425945 A

[0002] DE 199 13 164 C1

[0003] US 7487801 B2

[0004]

Claims

[1] Fastening element (1) with protective cap (2), wherein the protective cap (2) has an end face (5) and an opening (3) opposite the end face (5), in particular a cylindrical opening, for an external thread section (4) of the fastening element (1), characterized by that one or more predetermined breaking points (6) are arranged on the circumference (7) and / or the front side (5) of the protective cap (2). [2] Fastening element (1) with protective cap (2) according to claim 1, characterized by that at least one predetermined breaking point (6) is formed by a reduction in a wall thickness and / or by an opening (11) at one or more points on the circumference (7) of the protective cap (2). [3] Fastening element (1) with protective cap (2) according to claim 1 or 2, characterized by that a gripping means (8) is arranged on a part of the circumference (7) of the protective cap (2). [4] Fastening element (1) with protective cap (2) according to claim 3, characterized bythat the gripping means (8) extends in a direction facing away from the end face (5), in particular substantially parallel to a central axis (9) of the fastening element (1). [5] Fastening element (1) with protective cap (2) according to claim 3 or 4, characterized by that the gripping means (8) is adjacent to one or more predetermined breaking points (6). [6] Fastening element (1) with protective cap (2) according to one of the preceding claims, characterized by that the protective cap (2) is made of plastic.

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