Electromagnetic flowmeter

US4281552A · kind A · utility

Assignee

• Fischer & Porter GmbH · US

Inventors

• Peter Neal Nissen · Frederikssund, DK
• Wilfried Kiene · Menden, DE
• Eggert Appel · Dransfeld, DE

Key dates

• Filing date: Jul 5, 1979
• Grant date: Aug 4, 1981
• Expiry date: Jul 5, 1999

Classification

• Technology area (CPC G): Physics
• CPC primary: G01F1/586
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An electromagnetic flowmeter in which the fluid to be metered is conducted through a flow tube formed of nonmagnetizable metal and provided with an inner lining of electrical-insulating material. The fluid intercepts a transverse electromagnetic field established in the tube whereby the voltage induced in the fluid is transferred to a pair of electrodes disposed at diametrically-opposed positions on the tube to yield a signal indicative of flow rate. The electromagnet is constituted by at least one solid core surrounded by a coil to which a low-frequency excitation current is applied, the core having a cavity in a region therein which serves to reduce the mass of the core without, however, significantly affecting the intensity of the magnetic field produced thereby.