Patent · US Expired

Method and apparatus for fastener tensioning

US4104778A · kind A · utility

80Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 27, 1977
Grant dateAug 8, 1978
Priority date
Expiry dateJan 27, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49767
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A fastener tensioning method and apparatus for obtaining a desired degree of tension in a fastener. The apparatus includes a means for applying rotation to a fastener, a means for measuring the torque applied by the means for rotating the fastener, a means for determining a rate of change of torque applied to the fastener with respect to the rotation applied to the fastener, a means for detecting when the rate of change of torque with respect to rotation becomes a constant, a means for accomplishing a desired amount of rotation of the fastener beyond the rotation required to achieve the constant rate of change of torque with respect to rotation, and a means for shutting off the means for applying rotation to the fastener in response to the total desired rotation being achieved. The embodiment herein described improves the well-known "turn of the nut" method for fastener tensioning by providing that method with a well determined starting point.

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