Apparatus to measure the eccentricity of a shaft
US4057754A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 6, 1976 |
| Grant date | Nov 8, 1977 |
| Priority date | — |
| Expiry date | May 6, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/34
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A transducer is utilized to convert the eccentricity of a turbine shaft into a sinusoidal electrical voltage signal having a given frequency, amplitude and a DC bias. This electrical signal is provided to a circuit which periodically measures the maximum and minimum peaks of the sinusoidal signal. The frequency at which the latter measurements occur is related to the frequency of the sinusoidal input signal. The maximum and minimum levels of magnitude are stored periodically as DC levels and subtracted from each other to determine the absolute value of eccentricity. In addition the stored minimum value is compared with the sinusoidal signal to reduce the DC bias of the sinusoidal signal to a point where the negative peaks thereof are at zero.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.