BLIND RIVET-NUT AND METHOD FOR SECURING A COMPONENT TO A CARRIER

Abstract

A blind rivet-nut having an annular-flange-like setting head and a hollow shaft for securing a blind rivet-nut in an opening of a carrier. The hollow shaft has a free end having a threaded portion for receiving a threaded element of a tensioning tool. A clamping portion adjacent to the setting head forms a bead-like deformation when the tensioning tool is used to clamp the carrier between the bead-like deformation and the setting head. A threadless shaft portion is formed between the clamping portion and the threaded portion. The threadless shaft portion is threaded by a thread self-rolling or thread self-tapping fastener. The fastener is received in a positive-locking manner when the fastener is screwed into the thread formed on the previously threadless shaft portion. A method is also disclosed for securing a component to a carrier by a blind rivet-nut.

Claims

1. A blind rivet-nut having a setting head and a hollow shaft received in an opening defined by a carrier, wherein the hollow shaft has at a free end opposite the setting head, the free end includes a first threaded portion that is adapted to receive a threaded element of a tensioning tool, the hollow shaft having a clamping portion adjacent to the setting head, the clamping portion being adapted to form a bead-like deformation during a setting operation of the blind rivet-nut on the carrier to clamp the carrier between the bead-like deformation and the setting head, wherein a portion a threadless shaft portion is provided between the clamping portion and the first threaded portion, wherein a self-tapping fastener forms a second thread on the threadless shaft portion, and wherein the self-tapping fastener is attached in a positive-locking manner to the second thread.

2. The blind rivet-nut of claim 1, wherein the threadless shaft portion has a hole diameter which is smaller than a first diameter of the clamping portion and greater than a second diameter of the first threaded portion.

3. The blind rivet-nut of claim 1, wherein a wall of the threadless shaft portion has a thickness sufficient to have an inner thread formed in the wall.

4. The blind rivet-nut of claim 1, wherein a wall of the threadless shaft portion has a thickness that is sufficient to resist plastic deformation during a setting operation of the blind rivet-nut on the carrier.

5. An assembly comprising: a rivet-nut having a head, a free end, and a sleeve between the head and the free end; a carrier defining an opening that receives the rivet-nut, wherein the rivet-nut is compressed to form a bead securing the rivet-nut to the carrier; and a self-tapping fastener forming a thread on the sleeve that positively locks the self-tapping fastener to the thread.

6. The assembly of claim 5 wherein the rivet-nut is a blind rivet that is deformed by a tensioning tool that engages the free end to pull the free end towards the head and thereby form the bead.

7. The assembly of claim 5 wherein the sleeve has a smooth internal surface until the self-tapping fastener forms the thread on the smooth internal surface.

8. The assembly of claim 5 wherein the rivet-nut has an internal opening including an intermediate portion formed by a smooth internal surface that defines a hole having a smaller internal diameter than a clamping portion of the internal opening that is formed into the bead and a greater internal diameter than an end portion of the internal opening at the free end.

9. A method comprising: assembling a carrier defining an opening to a rivet-nut including a hollow shaft having an internal thread on a free end, a head, and an internal portion between the head and the free end; compressing the rivet-nut by pulling the free end toward the head to form a bead on the opposite side of the carrier from the head; and tapping a thread on the internal portion with a fastener.

10. The method of claim 9 further comprising: clamping the carrier between the head and the bead.

11. The method of claim 9 wherein the fastener is a self-tapping bolt.

12. The method of claim 9 wherein the step of compressing the rivet-nut is performed by a tensioning tool having a threaded end that is threaded into the internal thread on the free end to pull the free end toward the head and thereby form the bead.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is a cross-section of an embodiment of a blind rivet-nut according to the invention before a setting operation on a carrier,

[0020] FIG. 2 is a cross-section of the blind rivet-nut from FIG. 1 after the setting operation on the carrier, and

[0021] FIG. 3 is a cross-section of the blind rivet-nut from FIG. 2 which is set on the carrier and to which another component is secured.

DETAILED DESCRIPTION

[0022] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

[0023] In the different Figures, components which are equivalent in terms of their function are always given the same reference numerals so that they are generally also described only once.

[0024] FIG. 1 is a cross-section of an embodiment of a blind rivet-nut 1 made according to this disclosure before a setting operation on a carrier 2. FIG. 1 shows that the blind rivet-nut 1 has an annular-flange-like setting head 3 and a hollow shaft 4 which is integrally connected to and adjacent to the setting head 3.

[0025] The hollow shaft 4 of the blind rivet-nut 1 illustrated in FIG. 1 comprises at the free end thereof opposite the setting head 3 a threaded portion 5 for receiving a threaded element 6 which is fitted, for example, to a tension screw 7 as shown in FIG. 1. The tension screw 7 serves to set the blind rivet-nut 1 on the carrier 2, as will be further explained with reference to FIG. 2.

[0026] Furthermore, the hollow shaft 4 has a clamping portion 8 adjacent to the setting head 3 that deforms in a bead-like manner during a setting operation of the blind rivet-nut 1 on the carrier 2. The bead-like deformation 9 of the clamping portion 8 clamps the carrier against the setting head 3, as illustrated in FIG. 2.

[0027] In the embodiment of the blind rivet-nut 1 illustrated in FIG. 1, a threadless shaft portion 10 is constructed between the clamping portion 8 and the threaded portion 5. This threadless shaft portion 10, or sleeve, is constructed to receive a thread self-rolling or thread self-tapping screw 11 or bolt in a positive-locking manner when the screw/bolt is screwed into the shaft portion 10, as illustrated in FIG. 3.

[0028] FIG. 1 further shows that the threadless shaft portion 10 has a hole diameter 12 which is smaller than the diameter 13 of the clamping portion 8 and greater than the diameter 14 of the threaded portion 5. The hollow shaft 4 of the blind rivet-nut 1 as shown in FIG. 4 has a substantially constant outer diameter along the clamping portion 8, the threadless shaft portion 10 and the threaded portion 5. Different wall thicknesses are provided for the clamping portion 8, the threadless shaft portion 10 and the threaded portion 5. The wall thickness of the threadless shaft portion 10 is sized in such a manner that an inner thread can be rolled or cut in the threadless shaft portion 10. The blind rivet-nut 1 when set on the carrier 2 plastically deforms the clamping portion 8 but does not plastically deform the threadless shaft portion 10 during the setting operation.

[0029] As indicated in FIG. 1, the blind rivet-nut 1 is first introduced into the opening defined by the carrier 2 and a suitable setting tool, such as a tension screw 7 is used to set the blind rivet-nut 1. The threaded element 6 of the tension screw 7 is screwed into the threaded portion 5 of the blind rivet-nut 1 to apply an axial pulling force to the hollow shaft 4 of the blind rivet-nut 1.

[0030] FIG. 2 is a cross-section of the blind rivet-nut 1 from FIG. 1 after setting the blind rivet-nut on the carrier 2. The clamping portion 8 of the blind rivet-nut 1 is plastically deformed by the axial pulling force applied by the tension screw 7. The plastic deformation creates the bead-like deformation 9 of the clamping portion 8. The carrier 2 is clamped between the bead-like deformation 9 of the clamping portion 8 and the setting head 3 after the setting operation.

[0031] FIG. 3 is a cross-section of the blind rivet-nut 1 of FIG. 2 set on the carrier 2 and to which another component 15, for example, a metal sheet, is secured by means of the securing screw 11. The thread self-rolling or thread self-tapping securing screw 11 is screwed into the shaft portion 10 to secure the component 15 to the blind rivet-nut 1 or to the carrier 2. The shaft portion 10 is threadless before the self-tapping screw is screwed into the shaft portion 10. The self-tapping screw forms, rolls or cuts a thread into shaft portion 10 and the screw 11 is received in a positive-locking manner in the thread.

[0032] The blind rivet-nut according to the invention is used to secure a component to a carrier by means of a thread self-rolling or thread self-tapping screw or bolt. The blind rivet-nut, the securing arrangement and the securing method are, however, not limited to the embodiment described herein, but instead also include other embodiments which have the same effect.

[0033] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.