Method and apparatus for fastener tension inspection
US3962910A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1973 |
| Grant date | Jun 15, 1976 |
| Priority date | — |
| Expiry date | Aug 20, 1993 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25B23/1456
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A fastener tension inspection system for use with torque producing power tools such as nut runners, screwdrivers, or the like. The inspection system includes a means for measuring torque or other tension proportional function applied to a fastener and a means for measuring at least one additional parameter associated with fastener tightening; for example, time or rotation. With appropriate electronic circuitry, the torquing cycle is started by freerunning the fastener and bringing it up to a predetermined low level of torque sufficient to seat the fastener. Upon reaching the predetermined low level of torque, the means for measuring the additional parameter is initiated and continues until final torquing is completed. The predetermined minimum torque level on the fastener must be reached and a predetermined maximum torque level not exceeded within a predetermined range of the additional parameter or the fastener is rejected. The system is capable of detecting such common fastener defects as insufficient final torque, cross-threading, defective threads or thread stripping.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.