Electromagnetic flow meter

An electromagnetic flow meter in which a magnetic field is generated by excitation coil means provided in the outside of a conduit and electromotive force generated in electrodes attached on said conduit is detected to thereby measure a flow rate of a fluid flowing in said conduit, said electromagnetic flow meter comprising:

• a detection portion in which an axial length of said conduit is selected so as to be shorter than an inside diameter of said conduit;
• and
• correction means for correcting an output of said detection portion in accordance with conditions of a mate piping to which said detection portion is connected.

An electromagnetic flow meter comprising a conduit portion in which a fluid to be measured is made to flow, a magnetic circuit for exerting a magnetic field onto said conduit portion perpendicularly to an axial direction of said conduit portion, and a pair of electrodes arranged in a position so as to be in opposition to each other and so as to perpendicularly intersect a direction of flow of said fluid, in which said magnetic circuit includes a core made of a sheet of or a plurality of laminated sheets of magnetic material and disposed perpendicularly to the axial direction of said conduit portion, and in which flange attaching metal-fittings for attaching a flange of a mate piping to which said conduit portion is to be connected are provided on said core.

An electromagnetic flow meter comprising a conduit portion in which a fluid to be measured is made to flow, a magnetic circuit for exerting a magnetic field onto said conduit portion perpendicularly to an axial direction of said conduit portion, and a pair of electrodes arranged in a position so as to be in opposition to each other and so as to perpendicularly intersect a direction of flow of said fluid, in which said electromagnetic flow meter further comprises a core made of a sheet of or a plurality of laminated sheets of magnetic material so as to serve as said magnetic circuit as well as a support, said electrodes being mechanically fixed to said core through insulators, flange attaching metal-fittings mechanically fixed to said core, and coil means fixed on projecting pole portions of said core, said core, said electrodes, said flange attaching metal-fittings and said coil means being integrally embedded in resin molding, and in which an axial length of said conduit portion is selected so as to be shorter than an inside diameter of said conduit portion.

In an apparatus for measuring a flow rate by using an electromagnetic flow meter, an electromagnetic flow measurement correction device comprising:

• a parameter setting portion for setting parameters including conditions of a mate piping to which said electromagnetic flow meter is connected;
• a storage portion for storing span correction data previously set correspondingly to said parameters;
• and a correction operation portion for correcting a detection signal from said electromagnetic flow meter on the basis of said correction data to thereby output a flow rate measurement signal.