| 摘要 |
PURPOSE:To lessen the length of a pipe and thereby to reduce an inter-earthing- point resistance by a construction wherein only a magnetic pole giving a magnetic field to a fluid from the outside of the pipe passing the fluid through is disposed in the vicinity of the outer wall of the pipe, while exciting coils are disposed apart from the pipe. CONSTITUTION:In an electromagnetic flowmeter measuring the flow rate of a fluid flowing through a conduit pipe in water-works, a drainage or the like, a magnetic field is applied to the fluid flowing through a conduit pipe 13 by exciting coils perpendicularly to the flowing direction thereof, and the flow rate of the fluid is measured from an electromotive force induced in the fluid. In this flowmeter, exciting coils 17-19 are disposed above the pipe 13 and fitted on the side of the shorter magnetic pole (a) of a core 20. Thereby a detecting element having a pipe length lp and a magnetic pole area lcXW, which ae the minimum necessary for a pipe diameter D can be constructed irrespective of the form and size of the exciting coils working as a magnetic field generating source, and consequently, the effect of a common-mode noise voltage generated in a low- conductivity fluid in a small-diametler detector can be reduced. |
