Patent · US Expired

Tightening method and system

US4104779A · kind A · utility

24Cited by
3References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 29, 1976
Grant dateAug 8, 1978
Priority date
Expiry dateDec 29, 1996

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49766
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A preferred embodiment of the invention disclosed herein relates to a method of and tightening system for tightening a joint assembly including a fastener system to a yield point of one of the members in the assembly. According to the method, torque is applied and rotation is imparted to a fastener member, and the torque and rotational displacement of the fastener are determined at predetermined increments of rotation for use in determining the area between successive increments of rotation under the Torque-Rotation curve which could be plotted. The incremental areas are compared to determine when some member in the joint assembly has been tightened to its yield point or some similarly significant point. The tightening system includes a wrench and a control system associated with the wrench including measuring systems for developing a first signal representative of the torque applied to the fastener and a second signal representative of the rotation of the fastener. Both the first and second signals are fed to an incremental area calculating system included in the control system, which calculates and develops a signal representative of the area under the Torque-Rotation curve which…

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