Method and circuit for providing electrical runout reduction in rotating shaft vibration detection systems
US4134303A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 20, 1977 |
| Grant date | Jan 16, 1979 |
| Priority date | — |
| Expiry date | Jul 20, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M1/22
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and circuit for reducing by electrical runout subtraction, the runout signal portion of a composite runout signal and vibration signal, which runout subtraction signal is provided by a pre-programmed digital memory circuit module, PROM, that is selectively inserted into the circuit for a given rotating shaft. The PROM is accessed by a phase lock loop, master dynamic clock, synchronized to the tachometer signal, which provides the subtract signal in digital form that is changed to an analog signal and then fed with the composite signal to a differential amplifier circuit that subtracts the PROM waveform from the composite signal. In one mode the subtract amplifier circuit is inhibited in operation when the tachometer signal falls below a given CPM, or when the tachometer signal is lost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.