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:
Sep. 05, 2000
Filed:
Dec. 18, 1998
Alain Bazin, Villejuif, FR;
Schlumberger Industries, S.A., Montrouge, FR;
Abstract
The invention relates to a method of measuring the flow rate of a flowing fluid on the basis of two ultrasonic signals transmitted consecutively in mutually opposite directions between two ultrasonic transducers. In the method, n clock signals CK.sub.i, where i=1 to n, that are at mutual phase offsets of 2.pi./n are formed, the first clock signal, referenced CLS, that occurs immediately after a characteristic portion the first received ultrasonic signal SIG.sub.1 appears is identified and stored, the time t.sub.1 is determined that corresponds to the sum, over an integer number m of consecutive periods, of the times elapsed between the instant at which the characteristic portion of each of the m periods of the signal SIG.sub.1 appears, and the instant at which the following signal CLS appears, likewise, for the signal SIG.sub.2 received in the opposite direction, the time t.sub.2 is determined that corresponds to the sum, over m consecutive periods, of the times elapsed between the instant at which the characteristic portion of each period appears and the instant at which the following signal CLS appears, the difference .vertline.t2-t1.vertline. is taken, and the flow rate is deduced therefrom.