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:
Jul. 17, 1979
Filed:
Nov. 17, 1977
Applicant:
Inventors:
Carl-Gustaf Carlin, Tyreso, SE;
Stefan M Skyllermark, Nacka, SE;
Assignee:
Atlas Copco Aktiebolag, Nacka, SE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23Q / ;
U.S. Cl.
CPC ...
173-1 ; 173 12 ;
Abstract
A method and apparatus for tightening a screw joint to a predetermined axial load F.sub.p providing the spring constant k=F/.phi. of the joint is known, wherein the joint stiffness or torque/rotation radient dM/d.phi. is calculated during the tightening process and the torque application on the joint is interrupted as a torque level M.sub.s is obtained that according to the spring constant or axial load/rotation relationship F/.phi. and the calculated joint stiffness dM/d.phi. corresponds to the predetermined axial load F.sub.p.