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:
Jan. 01, 1980
Filed:
Sep. 12, 1978
Hokushin Electric Works, Ltd., Tokyo, JP;
Abstract
An electromagnetic flowmeter in which a low-frequency rectangular wave is supplied to the electromagnet coil of the flowmeter to produce an excitation current establishing a magnetic field which is intercepted by the fluid passing through the flow tube to induce a signal voltage in the electrodes disposed in the tube. This signal voltage is proportional to flow rate and is accompanied by an objectionable D-C noise component. To eliminate this noise component, the signal voltage is passed through a first high-pass filter, and to compensate for errors introduced by this filter, the signal voltage derived from the first filter is divided by a comparison voltage derived from the excitation current, but only after this comparison voltage passes through a second high-pass filter having essentially the same characteristics as the first filter.