Method and apparatus for monitoring the state of oscillation of the blades of a rotor
US4153388A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1977 |
| Grant date | May 8, 1979 |
| Priority date | — |
| Expiry date | Apr 26, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01H1/006
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pulse generator is used to emit a pulse train of specific frequency while two pick-ups--one adjacent a circumferential array of control lugs on the rotor and the other adjacent the blades--emit start counting and stop counting pulses. The number of pulses generated by an external pulse generator are counted during the time interval for the passage of two lugs past a pick-up and the time interval for the passage of two adjacent blades past a pick-up for each revolution of the rotor. A quotient is then obtained from the two pulse numbers for each revolution and the difference between the maximum and minimum values of the quotients obtained during continued rotation is determined. If the difference exceeds a preset critical value, an activity signal is generated, for example to set off an alarm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.