Patent · US Expired

Magnetic flowmeter with improved accuracy

US5544532A · kind A · utility

27Cited by
41References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 25, 1994
Grant dateAug 13, 1996
Priority date
Expiry dateMay 25, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/4902
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A monolithic flowtube for use with an electromagnetic flowmeter includes an inner portion formed of an improved purity dielectric material having a reduced number of mobile ions, a pair of electrodes adjacent the exterior surface of the inner portion and capacitively coupled thereto, and an outer layer of ceramic material adjacent the exterior surface of the inner conduit and electrodes. A method of manufacturing the flowtube includes the steps of forming a dielectric material into a substantially tubular conduit, depositing a conductive material, preferably a refractory metal, onto the exterior of the tubular conduit, forming an outer layer of ceramic material over the tubular conduit, and firing all components simultaneously in a reducing atmosphere to form a monolithic flowtube body. A magnetic flowmeter includes, in addition to a flow tube and a pair of electrodes, a magnetic field source for creating a time-varying magnetic field passing through the flow tube, and special circuitry, including secondary coil windings, for electrically altering the average direction of the magnetic field relative to the flow tube access so as to minimize the zero offset present in the output flo…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.