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:
Mar. 10, 1992
Filed:
Mar. 05, 1990
Applicant:
Inventors:
Lloyd H Wipperman, Rochester Hills, MI (US);
Curt D Gilmore, Fenton, MI (US);
Assignee:
Dresser Industries, Inc., Dallas, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B23Q / ;
U.S. Cl.
CPC ...
173-1 ; 173-5 ; 73761 ; 81469 ;
Abstract
A method and apparatus for recovering torque lost due to joint relaxation in threaded fastener assemblies or joints. The present invention is especially adapted for use with medium-to-short or gasketed joints. In the practice of an exemplary embodiment of the invention, the torque of an electric nutrunner is pulsed at the end of a fastener tightening cycle between programmed maximum and minimum torque values which have been selected to overcome the static to dynamic torque ratio of the joint while maintaining the motor and gearing of the nutrunner in a loaded condition to ensure maximum nutrunner durability.