Programmable pulsed torque recovery system
US5094301A · kind A · utility
14Cited by
11References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1990 |
| Grant date | Mar 10, 1992 |
| Priority date | — |
| Expiry date | Mar 5, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B23/147
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for recovering torque lost due to joint relaxation in threaded fastener assemblies or joints. The present invention is especially adapted for use with medium-to-short or gasketed joints. In the practice of an exemplary embodiment of the invention, the torque of an electric nutrunner is pulsed at the end of a fastener tightening cycle between programmed maximum and minimum torque values which have been selected to overcome the static to dynamic torque ratio of the joint while maintaining the motor and gearing of the nutrunner in a loaded condition to ensure maximum nutrunner durability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.