Fastener insert with improved anti-rotation and pull-out characteristics
US4007659A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 13, 1975 |
| Grant date | Feb 15, 1977 |
| Priority date | — |
| Expiry date | Feb 13, 1995 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B19/1072
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A blind fastener system comprising a ductile sleeve having an expansion portion of small inner diameter in a thin workpiece and having a bulbing portion of larger inner diameter extending on the blind side of the workpiece, and a threaded expander member having an expander portion for expanding the sleeve expansion portion and a head portion for bulbously deforming the sleeve bulbing portion, both actions occurring on axially pulling the expander member. The expander portion has a tapered, radiused leading end followed by a configured (splined, knurled, etc.) portion for the remainder of the active length. The protrusions of the configured portion leave a void volume between them and between the minor and major diameters of the protrusions, and the volume of the sleeve expansion portion between the small inner diameter and the projection of the large inner diameter is approximately 0.5 to 0.8 of the void volume of the configured portion. The protrusions have blunt outer surfaces. The expander member may be a nut, in which case the minor diameter of the protrusion is at least 1.23 times the major diameter of the internal threads of the expander member, which threads are inwardly of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.