Electromagnetic flowmeter of the residual magnetism type
US4601209A · kind A · utility
16Cited by
3References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 12, 1985 |
| Grant date | Jul 22, 1986 |
| Priority date | — |
| Expiry date | Apr 12, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/586
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electromagnetic flowmeter has identical exciting coils coupled to portions which exhibit residual magnetism. A control circuit delivers short durations of current to each coil such that the current polarity in each coil determines the polarity of the magnetic flux across the conduit due to each residual magnetic portion. Four states of magnetic flux are repeatedly produced, zero, of one polarity, zero and of the other polarity. Flow note is determined by the difference between sampled voltages in a zero state and a directly succeeding state to eliminate noise components.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.