Blind fasteners and methods of fastening

Patent metadata

Field	Value
Publication number	US-12276294-B2
Application number	US-201917594569-A
Country	US
Kind code	B2
Filing date	May 15, 2019
Priority date	May 15, 2019
Publication date	Apr 15, 2025
Grant date	Apr 15, 2025

Abstract

Blind fasteners and methods of fastening are provided. A blind fastener comprises a sleeve and a mandrel. The sleeve is adapted for installation into a threaded bore in a structure. The sleeve comprises a head portion configured to receive a torque, a first sleeve end, a second sleeve end, an elongate portion extending intermediate the first sleeve end and the second sleeve end, and a cavity extending from the first sleeve end to the second sleeve end. The mandrel is at least partially disposed through the cavity of the sleeve. The mandrel comprises a first mandrel end disposed adjacent to the first sleeve end. The first mandrel end comprises an enlarged portion having a diameter greater than a diameter of the cavity. The elongate portion is configured to at least partially deform into threads of the threaded bore responsive to forcible contact between the enlarged portion and the sleeve.

First claim

What is claimed is:

1. A blind fastener comprising:
a sleeve adapted for installation into a threaded bore in a structure, the sleeve comprising
a head portion wherein the head portion comprises at least one feature configured to receive a torque selected from the group consisting of a substantially flat side, a rib, a spline, an indent, a knurl, a lobe, a bore, and a tab,
a first sleeve end,
a second sleeve end,
an elongate portion extending intermediate the first sleeve end and the second sleeve end, and
a cavity extending from the first sleeve end to the second sleeve end; and

a mandrel at least partially disposed through the cavity of the sleeve, the mandrel comprising
a first mandrel end disposed adjacent to the first sleeve end and comprising an enlarged portion having a diameter greater than a diameter of the cavity, wherein the enlarged portion is hollow;

wherein the elongate portion is configured to at least partially deform into threads of the threaded bore thereby forming external threads on the elongate portion and the diameter of the enlarged portion is configured to be at least partially reduced responsive to forcible contact between the enlarged portion and the sleeve,
wherein the blind fastener is capable of removal from the threads in the threaded bore after forming the external threads by rotation of the blind fastener.

2. The blind fastener of claim 1 , wherein the external threads is configured to correspond to the threads of the threaded bore.

3. The blind fastener of claim 1 , wherein the mandrel further comprises:
a second mandrel end comprising a pull region, and
a shank region extending between the first mandrel end and the second mandrel end, wherein the shank region is at least partially disposed through the cavity of the sleeve.

4. The blind fastener of claim 3 , wherein the shank region comprises at least one of a generally smooth region, threads, an annular shoulder, and a groove.

5. The blind fastener of claim 3 , wherein the pull region comprises at least one of a generally smooth region, threads, an annular shoulder, and a groove.

6. The blind fastener of claim 1 , wherein the mandrel comprises a breakneck groove.

7. The blind fastener of claim 1 , wherein the sleeve is generally cylindrical and the mandrel is generally cylindrical.

8. The blind fastener of claim 1 , further comprising a flange disposed adjacent to the head portion.

9. The blind fastener of claim 1 , wherein the blind fastener comprises at least one of a metal, a metal alloy, and a composite material.

10. The blind fastener of claim 1 , wherein the structure comprises at least one of a metal, a metal alloy, and a composite material.

11. The blind fastener of claim 1 , wherein the structure is configured as at least one of an aerospace part or component, an automotive part or component, a transportation part or component, and a building and construction part or component.

12. A blind fastener comprising:
a sleeve comprising
a head portion, wherein the head portion comprises at least one feature configured to receive a torque selected from the group consisting of a substantially flat side, a rib, a spline, an indent, a knurl, a lobe, a bore, and a tab,
a first sleeve end,
a second sleeve end,
an elongate portion extending intermediate the first sleeve end and the second sleeve end, and
a cavity extending from the first sleeve end to the second sleeve end; and

a mandrel at least partially disposed through the cavity of the sleeve, the mandrel comprising
a first mandrel end disposed adjacent to the first sleeve end and comprising an enlarged portion having a diameter greater than a diameter of the cavity, wherein the enlarged portion is hollow;

wherein the elongate portion is configured to at least partially deform into threads of the threaded bore thereby forming external threads on the elongate portion and the diameter of the enlarged portion is configured to be at least partially reduced responsive to forcible contact between the enlarged portion and the sleeve,
wherein the blind fastener is capable of removal from the threads in the threaded bore after forming the external threads by rotation of the blind fastener.

13. A method for fastening, the method comprising:
inserting a blind fastener into a threaded bore in a structure, the blind fastener comprising:
a sleeve adapted for installation into the threaded bore, the sleeve comprising
a head portion,
a first sleeve end,
a second sleeve end,
an elongate portion extending intermediate the first sleeve end and the second sleeve end, and
a cavity extending from the first sleeve end to the second sleeve end; and

a mandrel configured to be at least partially disposed through the cavity of the sleeve, the mandrel comprising
a first mandrel end disposed adjacent to the first sleeve end and comprising an enlarged portion having a diameter greater than a diameter of the cavity, wherein the enlarged portion is hollow; and

deforming the elongate portion onto threads of the threaded bore and reducing the diameter of the enlarged portion, thereby securing at least a portion of the blind fastener into the structure.

14. The method of claim 13 , wherein deforming the sleeve further comprises forming external threads on the elongate portion, wherein the external threads correspond to the threads of the threaded bore.

15. The method of claim 13 , further comprising, after the inserting, forcibly contacting the second sleeve end of the blind fastener with an anvil of an installation tool and moving a pull region of a second mandrel end of the mandrel distal from the second sleeve end utilizing the installation tool until the mandrel fractures.

16. The method of claim 15 , further comprising:
deforming the sleeve on a first side of the structure, and swaging the second sleeve end onto a shank region of the sleeve on an oppositely disposed second side of the structure.

17. The method of claim 13 , wherein the structure is configured as at least one of an aerospace part or component, an automotive part or component, a transportation part or component, and a building and construction part or component.

Assignees

• Howmet Aerospace Inc

Inventors

• Pierce Troy Don
• Wilcox Robert B
• Branch Justin

Classifications

• F16B19/1045

  fastened by a pull - mandrel or the like (F16B19/109 takes precedence) · CPC title

• F16B37/002

  cutting threads during screwing; removing paint or dirt layers covering threaded shanks · CPC title

• F16B13/065

  fastened by extracting the screw, nail or the like · CPC title

• F16B19/1054

  the pull-mandrel or the like being frangible · CPC title

• F16B19/1072 Primary

  the pull-mandrel or the like comprising a thread and being rotated with respect to the rivet, thereby mechanically expanding and fastening the rivet (nuts fastened by riveting F16B37/067) · CPC title