The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 28, 1980
Filed:
Jul. 31, 1978
Hollis B Merrell, Renton, WA (US);
The Boeing Company, Seattle, WA (US);
Abstract
An improved interference fit, fatigue-rated pin-type, nondeformable fastener and joints formed thereby are disclosed in countersunk flush head and protruding flat head embodiments, each characterized by a straight interference fit shank with a lead-in convex shoulder adjacent its threaded end operable to cold work the wall material of the straight fastener hole during fastener insertion, and with the shank progressively expanded in a concave curvilinear profile to its head end starting at a location preferably intermediate the ends of the shank. Curvature of the expansion profile fairs smoothly at relatively large radius into the straight intermediate portion of the shank. At its opposite end, the expansion profile curvature merges into a relatively sharp curvature of very small radius (i.e., of the order of 1% of the first and larger radius) that fairs smoothly into the lower face of the fastener head. Fatigue failures and corrosion problems in the fastener hole wall material starting at the hole entrance, and in some instances problems with warpage of a structural member caused by fastener installation are substantially avoided by the improved fastener.