Patent · US Expired

Method of and apparatus for controlling nut runner

US4908926A · kind A · utility

55Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 1988
Grant dateMar 20, 1990
Priority date
Expiry dateDec 22, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49863
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

The output shaft of a nut runner for tightening a fastener such as a bolt is first rotated with a first torque at a first speed. When the tightening torque of the output shaft reaches a preset switching torque, the first torque first speed rotation of the output shaft is interrupted, and thereafter the output shaft is rotated with a second torque at a second speed. When the tightening torque then reaches a preset snug torque, the second torque second speed rotation of the output shaft is interrupted, and thereafter the output shaft is rotated with a third torque at a third speed. When the tightening torque reaches a preset final torque, the third torque third speed rotation of the output shaft is stopped, thus completing the tightening of the fastener.

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