Current selection circuitry for magnetic flowmeter
US5639970A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1995 |
| Grant date | Jun 17, 1997 |
| Priority date | — |
| Expiry date | Jul 17, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/60
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic flowmeter system provides a volumetric flow rate output and includes flowmeter electronics for coupling to a flowtube assembly. The flowtube assembly includes a coil which receives a magnetic field producing coil current from a supply circuit in the flowmeter electronics. The coil produces a magnetic field which generates an EMF in the field representative of flow. An EMF sensor senses the generated EMF and provides an output indicating flow. The supply circuitry is coupled to coil wires of the coil and is responsive to a control signal. A sensor senses the frequency response of the coil and generates a sensor output. A comparator compares the sensor output with a predetermined level and provides a comparator output based upon the comparison. Control circuitry provides the magnitude control signal to the current based upon the comparison.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.