Transit-time difference type ultrasonic flowmeter
A transit-time difference type ultrasonic flowmeter comprises a pair of ultrasonic transducers mounted on a flow tube at an upstream side and a downstream side respectively, a switching device for switching the operational mode of each of the transducers alternatively to its transmitting or receiving mode, an amplifier for amplifying the signal received by the transducer of the receiving side, and a data reduction equipment includes an analog-digital converter and a digital signal processor; the converter converts the waveform into a plurality of voltage-time data sets; and the processor picks up an object peak of the voltage-time data sets on the basis of the time, or the data on the voltage, or determines the peaks of maximum voltage included within the waveform of the voltage-time data sets as an object peak, estimates at least one zero-cross point confined by the object peak or a peak adjacent to the object peak through the calculation made on the plurality of voltage-time data sets distributing along the time axis close to the zero-cross points, and finds the time required for propagating the wave from one zero-cross point or the average time required for propagating the wave from a plurality of zero-cross points.
Tokyo Keiso Kabushiki-Kaisha
G G
G01F G01F
inventional inventional
Kunikazu Toru Tamotsu
Shigeta Fujii Kobayashi