Method and apparatus for remotely detecting pressure, force, temperature, density, vibration, viscosity and speed of sound in a fluid
US6286361A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1998 |
| Grant date | Sep 11, 2001 |
| Priority date | — |
| Expiry date | Jan 5, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/02827
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for detecting pressure in a hollow fan blade of a turbofan gas turbine engine comprises a magnetostriction transducer arranged in a sub chamber of the fan blade which is interconnected to a main chamber. A magnetic coil is arranged in the fan casing of the turbofan remote from the fan blade, and an alternating current is supplied from a supply to the magnetic coil to produce an alternating magnetic field. The alternating magnetic field causes the magnetostriction transducer to generate vibrations in the fan blade and the magnetostriction transducer. A magnetic search coil detects changes in the magnetic field, which corresponds to the vibrations, and a processor analyses the vibrations to determine if there has been a change in the resonant frequency of the vibrations which is indicative of a change in the pressure in the fan blade. The processor supplies a signal to a display or to an alarm. The change in the pressure is indicative that the fan blade is cracked and needs replacing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.