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. 20, 1998
Filed:
Apr. 25, 1996
Edwin G Haas, Sayville, NY (US);
James R Kennedy, Southampton, NY (US);
Alvin Levy, Stony Brook, NY (US);
John M Papazian, Great Neck, NY (US);
Northrop Grumman Corporation, Los Angeles, CA (US);
Abstract
A gauge for measuring an out-of-plane surface displacement profile around a cold-worked fastener hole in relation to the distribution of residual compressive stresses around the hole and related fatigue life. The gauge has a deformable strain sensor positionable to be deformed in accord with the out-of-plane surface of the structural material circumferentially surrounding the cold-worked hole. A measurement reporting readout device is in communication with the strain sensor and relates three-dimensional surface-profile measurement data in accord with strain sensor deformation to determine or verify the cold expansion magnitude, uniformity and consequent fatigue life through three-dimensional elastoplastic finite element comparative analyses and/or experimental measurements for a hole in any material of given thickness.