System, device and method for measurement of fastener loading
US10345173B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 12, 2017 |
| Grant date | Jul 9, 2019 |
| Priority date | — |
| Expiry date | Aug 4, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L1/255
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In the present disclosure, embodiments including a system, device and methods are disclosed for accurately measuring the strain or extension of a fastener that occurs as the nut on the fastener is tightened and the fastener is put under load. The measurement technique is based on measurement of the time for an ultrasonic wave generated on one end of the fastener to travel a round trip through the fastener. As the fastener is tightened, the applied stress causes an associated increase in length. This length can be determined from a measurement of the increase in transit time. In various embodiments, the disclosed device and method uses laser ultrasonic testing (LUT), in which a pulsed laser generates the ultrasonic wave and a type of laser vibrometer detects the wave when it returns to the position of generation following a combination of longitudinal wave reflections and a mode conversion to a shear wave.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.