| 摘要 |
An electromagnetic flowmeter having a frame assembly formed by an octagonal metal frame within which are mounted a pair of electromagnets and a pair of electrode holders. The electromagnets are secured to one set of opposing sides of the frame along a first transverse axis which passes through the geometric center of the frame while the holders are secured to another set of opposing sides along a second tranverse axis which passes through the center at right angles to the first axis. The frame assembly is encapsulated within a generally cylindrical plastic insulating body of polymeric material having a longitudinal bore therein defining a flow conduit whose flow axis passes through the geometric center of the frame and is perpendicular both to the first and second transverse axes whereby when the fluid flows therethrough it intersects the magnetic lines of flux produced by the electromagnets. The resultant voltage induced in the fluid is a function of its flow rate and is picked up by the electrodes to provide a flow rate signal. To prevent the plastic body from cracking as a result of differences between the thermal coefficient of expansion of the metal frame and that of the polymeric material, an interfacial layer is formed therebetween having elastomeric properties.
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