Steam turbine blade arrival time processor with automatic gain control
US5015949A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1988 |
| Grant date | May 14, 1991 |
| Priority date | — |
| Expiry date | Dec 22, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01H1/006
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for detecting turbine blade passing times includes a sensor for producing an input signal each time a blade passes the sensor. Automatic gain control circuitry including a digital multiplier, peak detector and error amplifier regulates the amplitude of the input signal. A zero-crossing detector produces an output signal each time the input signal crosses a reference axis. A pre-trigger comparator produces a gating signal coinciding with the expected arrival time of the blade at the sensor. A gating device is responsive to the gating signal for conducting output signals which occur during the expected arrival time of the blade at the sensor. A monostable vibrator produces a digital pulse coinciding with the time at which the blade passes the sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.