Ultrasonic load indicating member, apparatus and method
US4899591A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 9, 1989 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Feb 9, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49005
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of measuring the load in a member subjected to longitudinal stress, a load measuring device and a fastener tightening device using the method of measuring, a load indicating member and a load indicating fastener for use in conjunction with the method of measuring, a method of making the load indicating fastener, a method of tightening the load indicating fastener and a transducer for instrumenting a load bearing member are each disclosed and claimed. A thin piezoelectric sensor consisting of a piezoelectric film sandwiched between two thin electrodes is permanently mechanically and acoustically coupled to the upper surface of a member and is used to determine the length, tensile load, stress, or other tensile load dependent characteristic of the member by ultrasonic techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.