The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 20, 1999
Filed:
Dec. 28, 1995
Shiquan Wang, Northboro, MA (US);
Peter B Lewis, North Attleboro, MA (US);
Norman O Fonteneau, Acushnet, MA (US);
Vincent W Devore, Farmington, ME (US);
The Foxboro Company, Foxboro, MA (US);
Abstract
A magnetic flowmeter has a tube for supporting fluid flow and a circuit for indicating when the tube is empty. The circuit includes an amplifier connected to two electrodes in the tube and a variable resistor. The amplifier produces an oscillating signal when the tube is empty. The circuit is calibrated for a particular fluid by finding a range of resistances for the variable resistor at which the circuit provides an accurate indication that the tube is empty, and storing information in the processor indicating a resistance in the range for the fluid.