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. 22, 1986
Filed:
May. 29, 1984
Jeffrey C O'Neil, Tulsa, OK (US);
Nusonics, Inc., Tulsa, OK (US);
Abstract
A timing means for determining the time of travel of ultrasonic pulses between a transmitter and a receiver immersed in a fluid. The first time instant is determined when the transmitter transmits an ultrasonic pulse in the fluid. A second time instant is determined when the ultrasonic wavelet has been detected, converted to electrical signal, and the zero crossing time of the electrical wavelet after a selected positive peak is determined. Timing means are provided to determine the time interval between the first and second time instants. This is done by having a coarse time clock and counter. The number of full clock periods before the second instant is determined, and a ramp of voltage is generated having a known rate of rise. The ramp is negatively biased and the bias voltage is varied until the ramp voltage reaches zero at the second instant. The transmitter upstream is fired, and the wavelet is detected at the downstream transducer. Simultaneously, or sequentially the downstream transducer is powered to generate a wavelet and the second wavelet is detected at the upstream transducer. The rate of flow of the fluid is a function of the difference between these two time intervals.