FLEXURAL-VIBRATION ULTRASONIC TRANSDUCER FOR GASEOUS MEDIA Russian patent published in 1998 - IPC

FIELD: nondestructive tests of materials and parts through gaseous media for controlling objects in air, measuring level of liquids and loose materials, etc. SUBSTANCE: transducer has case, bimorph in the form of thin metal disk carrying piezoelectric disk on one of its ends, horn, and metal washers with axisymmetric stepped inner hole to secure bimorph in case; diameter of piezoelectric disk is smaller than λ_иfmax/2, where λ_иfmax is wavelength of bimorph flexural vibrations at its upper working frequency. Bimorph has radial slits which divide it into pairs of opposing sectors whose radius is other than that of adjacent pairs. Metal screens are placed at certain distance from effective and rear ends of bimorph; placed in center of screen at effective end of piezoelectric disk is matching structure whose diameter equals that of piezoelectric disk. EFFECT: enlarged ultrasonic operating frequency range and improved efficiency of transducer. 5 cl, 1 dwg