Blind fasteners

Patent metadata

Field	Value
Publication number	US-10006478-B2
Application number	US-201615001979-A
Country	US
Kind code	B2
Filing date	Jan 20, 2016
Priority date	Jan 22, 2015
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

A fastener includes a sleeve, a core bolt, and an insert. The sleeve includes a first portion having a first inner diameter, a second portion having a second inner diameter, and a step intermediate the first and second portions. The core bolt includes a cylindrical portion having a first diameter, a threaded portion having a major diameter, and a thread run-out intermediate the cylindrical and threaded portions. The insert is disposed within the sleeve and is sized and shaped to be retained between the step of the sleeve and the thread run-out of the core bolt when the fastener is in a pre-installation position. The fastener compresses the insert between the step of the sleeve and the thread run-out of the core bolt by an installation motion of the core bolt. The insert deforms away from the core bolt to initiate formation of a bulb in response to the compression.

First claim

What is claimed is:

1. A fastener, comprising:
a sleeve having a tubular portion, a first end, a second end opposite said first end, and a head located at said first end, said tubular portion including a first portion proximate to said first end and having a first inner diameter, a second portion adjacent said first portion and having a second inner diameter that is less than said first inner diameter of said first portion, a third portion proximate to said second end and having an internal threads, and a step located intermediate said first and second portions;
a core bolt disposed within said sleeve and having a first end, a second end opposite said first end of said core bolt, and a shank portion between said first and second ends of said core bolt, said shank portion including a threaded portion proximate to said second end of said core bolt including an external thread, and a thread run-out said external thread of said threaded portion engage threadedly said internal thread of said sleeve; and
an insert disposed within said sleeve and encircling a portion of said core bolt, said insert being sized and shaped to abut and be retained between said step of said sleeve and said thread run-out of said core bolt when said fastener is in a pre-installation position,
wherein said insert is adapted to be compressed between said step of said sleeve and said thread run-out of said core bolt by an installation motion of said core bolt with respect to said sleeve before said installation motion of said core bolt generates a compressive load on said sleeve, and wherein said insert is adapted to deform away from said core bolt to initiate formation of a bulb at said second end of said sleeve in response to said compression.

2. The fastener of claim 1 , wherein said insert is made from copper.

3. The fastener of claim 2 , wherein said sleeve includes a band annealed portion proximate said insert.

4. The fastener of claim 3 , wherein said band annealed portion is band annealed by one of a laser and a radio frequency induction coil.

5. The fastener of claim 3 , wherein said insert includes a tubular member having an internal thread engaged threadedly with said external thread of said threaded portion of said core bolt.

6. The fastener of claim 5 , wherein said core bolt includes a head at said first end.

7. The fastener of claim 6 , wherein said head of said sleeve includes a pocket sized and shaped to receive said head of said core bolt.

8. The fastener of claim 7 , wherein said insert is sized such that when said fastener is in its pre-installation position, said core bolt is positioned within said sleeve such that said core bolt can be rotated approximately two to three times with respect to said sleeve before said head of said core bolt seats within said pocket of said sleeve.

9. The fastener of claim 8 , wherein said core bolt includes an annular groove adjacent said thread run-out.

10. The fastener of claim 8 , wherein said core bolt includes a splined head.

11. The fastener of claim 10 , wherein said insert is sized such that a diameter of said bulb is greater than one and one half times an outer diameter of said tubular portion of said sleeve.

Assignees

• Alcoa Inc
• Arconic Inc

Inventors

• Hufnagl Gerhart
• Desalvo Douglas
• Torrence Randy

Classifications

• F16B19/1072

  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

• F16B19/1054

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

• F16B13/124

  fastened by inserting a threaded element, e.g. screw or bolt (F16B13/122, F16B13/128 take precedence) · CPC title

• F16B13/0866

  with prongs penetrating into the wall of the hole by a retractile movement of a threaded member · CPC title

• F16B13/066 Primary

  fastened by extracting a separate expander-part, actuated by the screw, nail or the like · CPC title