METHOD OF ULTRASONIC TEST OF THICKNESS OF ARTICLES Russian patent published in 1998 - IPC

FIELD: ultrasonic measurement of thickness. SUBSTANCE: method consists in excitation of ultrasonic oscillations in article, in determination of derivative of optimally filtered received signal reflected from lower surface of article, in computation of its absolute value and in determination of point of maximum. Time of delay of echo signal is determined in point of minimal error of measurement of time delay corresponding to maximum of absolute value of derivative. Device proposed for realization of given method is composed of synchronizer, generator of probing pulses, emitting electroacoustic converter, receiving electroacoustic converter, input amplifier, optimal filter and meter of time intervals electroacoustically connected in series. Delay of signal at output of filter is proportional to measured thickness. Signal-to-noise ratio increases thanks to optimal filtration. EFFECT: increased precision of determination of both thicknesses of elongated sheet materials and diameters of bars. 4 dwg