Multi-piece fastener with self-indexing nut

• US 8,555,481 B2
• Filed: 03/05/2012
• Issued: 10/15/2013
• Est. Priority Date: 09/02/2005
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Porter, John R., Rufin, Antonio
• Primary Examiner(s): Bryant, David
• Assistant Examiner(s): CIGNA, JACOB JAMES
• Application Number:
  US13/400,354
• Publication Number:
  US 20120144653A1
• Time in Patent Office: 589 Days
• Field of Search: 411/116, 411190-337, 411/388, 411/389, 295/250.2
• US Class Current: 29/525.02
• CPC Class Codes: B64C 1/06 Frames; Stringers; Longerons ; Fuselage sections
• CPC Class Codes: B64C 1/26 Attaching the wing or tail units or stabilising surfaces
• CPC Class Codes: F16B 5/0275 the screw-threaded element having at least two axially separated threaded portions F16B5/0283 takes precedence
• CPC Class Codes: Y10T 29/49948 Multipart cooperating fastener [e.g., bolt and nut]
• CPC Class Codes: Y10T 403/75 having a joining piece extending through aligned openings in plural members

Abstract

According to a preferred embodiment, a multi-piece fastener with self-indexing nut is disclosed. The multi-piece fastener is designed for use in low clearance areas such as aircraft wing side-of-body joint locations. The multi-piece fastener comprises a stud comprising an elongated part extending between a first end face and a second end face, a threaded head fastener, a threaded tail fastener, and a wrenching feature. A self-indexing feature is provided on the stud and head fastener which allows automatic orientation of the head fastener with respect to the stud.

Claims

1. A method of coupling a first member to a second member, comprising:

positioning a threaded head fastener having a top end and a bottom end over a hole extending through the first member and the second member, such that the bottom end is proximate an outer surface of the first member, the threaded head fastener comprising a stop indentation in an outer surface of the top end;

providing a cylindrical stud having a first end face, a second end face, a first threaded area spaced from said first end face and extending to an unthreaded central area, a second threaded area spaced from said second end face and extending to said unthreaded central area, and an unthreaded stop projection area extending between said second threaded area and said second end face, said unthreaded stop projection area having a stop projection;

rotating the threaded head fastener around the second threaded area until the stop projection engages with the stop indentation in the outer surface of the top end of the threaded head fastener to prevent rotation of the threaded head fastener with respect to the cylindrical stud;

rotating a threaded tail fastener around the first threaded area; and

engaging a wrenching feature positioned adjacent to and affixed to the first end face of the cylindrical stud to restrain the cylindrical stud while the threaded tail fastener is rotated.

2. The method of claim 1, wherein the wrenching feature comprises a spline recess formed in the first end face of the cylindrical stud.

3. The method of claim 1, wherein:

the wrenching feature extends past the first end face; and

the method further comprises breaking off the wrenching feature after the first member is secured against the second member.

4. The method of claim 1, further comprising inserting the second end face of the cylindrical stud through the hole in the second member and then the hole in the first member.

5. The method of claim 1, wherein:

the stop projection is spring loaded; and

rotating the threaded head fastener further comprises rotating the threaded head fastener until the stop projection protrudes out from the stop indentation.

6. The method of claim 5, wherein:

the stop projection is movable between a depressed position and a raised position; and

the stop projection is in the depressed position while the threaded head fastener is being rotating and the stop projection moves to the raised position upon protruding out from the stop indentation.

7. A method of coupling a skin element to a chord assembly having an internal reduced clearance section in an aerospace wing side-of-body joint assembly comprising:

positioning a threaded head fastener having a top end and a bottom end in the internal reduced clearance section over a hole extending through the skin element and the chord element, such that the bottom end is proximate an inner surface of the chord element, the threaded head fastener comprising a stop indentation in an outer surface of the top end;

providing a cylindrical stud having a first end face, a second end face, a first threaded area spaced from said first end face and extending to an unthreaded central area, a second threaded area spaced from said second end face and extending to the unthreaded central area, and an unthreaded stop projection area extending between the second threaded area and the second end face, the unthreaded stop projection area having a stop projection;

rotating the threaded head fastener around the second threaded area until the stop projection engages with the stop indentation in the outer surface of the top end of the threaded head fastener to prevent rotation of the threaded head fastener with respect to the cylindrical stud;

engaging a threaded tail fastener with the first threaded area;

rotating the threaded tail fastener until the skin element is secured against the chord element; and

engaging a wrenching feature positioned adjacent to and affixed to the first end face of the cylindrical stud to restrain the cylindrical stud while the threaded tail fastener is rotated.

8. The method of claim 7, wherein the wrenching feature comprises a spline recess formed in the first end face of the cylindrical stud.

9. The method of claim 7, wherein:

the wrenching feature extends past the first end face; and

the method further comprises breaking off said wrenching feature after the skin element is secured against the chord element.

10. The method of claim 7, further comprising inserting the second end face of the cylindrical stud through the hole in the skin element and then the hole in the chord assembly.

11. The method of claim 7, wherein:

the stop projection is spring loaded; and

rotating said threaded head fastener further comprises rotating said threaded head fastener until said stop projection protrudes out from said stop indentation.

12. The method of claim 11, wherein:

said stop projection is movable between a depressed position and a raised position; and

said stop projection is in said depressed position while said threaded head fastener is being rotating and said stop projection moves to said raised position upon protruding out from said stop indentation.