Patent · US Expired

Method and apparatus for tightening threaded fastener assemblies

US4375120A · kind A · utility

37Cited by
6References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 7, 1980
Grant dateMar 1, 1983
Priority date
Expiry dateApr 7, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/53687
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

Apparatus and method for tightening assemblies held together by threaded fasteners. The desired tightened condition is achieved by calculating the tightening torque required to induce a desired preload in the threaded fastener and comparing this calculated tightening torque with the torque being imparted to the fastener to tighten the assembly. When the two torques are equal, the torque imparted to the fastener is stopped. The tightening torque is calculated by identifying properly the relationship between the torque-rotation curve through which the assembly is taken as it is being tightened and the preload-rotation curve for the assembly.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.