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:
Jul. 09, 1985
Filed:
Nov. 07, 1983
Jeffrey S Gutterman, Hilton, NY (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An acoustic fluid flow meter determines the flow velocity or volumetric flow from a measurement of the phase shift of acoustic signals propagated upstream and downstream along an acoustical path in the fluid. High resolution measurements of the phase difference of transmitted and received signals represent the fractional wavelength which exceeds the integral number of waves along the acoustic path. The low resolution determination of the integral and fractional number of waves for each direction is made by measuring the fractional phase shift at one frequency of the acoustic signal and again at a slightly different frequency of the acoustic signal. The difference of those phase shift measurements is proportional to the number of waves along the path for a given direction of propagation. That value is combined with high resolution fractional phase shift measurement to obtain a high resolution total wave number value for each direction of propagation. The difference of those two values then is proportional to the fluid flow.