PIEZOELECTRIC TRANSDUCER FOR GASEOUS MEDIUM Russian patent published in 1997 - IPC

FIELD: automatic ultrasonic check-up of liquid and gas level in enclosed vessels. SUBSTANCE: transducer has piezoid 1 in the form of disk, case 2, diaphragm 3, deflector 4, adapter pipe 5. Interior of case 2 is filled with compound 11. Distances between effective surface of piezoid and diaphragm h_d as well as between its rear surface and deflector h_def satisfies expressions on condition that diaphragm thickness Δd ≅ 5•10λ_d, deflector thickness Δ_def≥ 10^-1λ_def, and piezoid disk thickness Δh ≅ 1,5•10^-1λ_p, where λ_d,λ_c,λ_def,λ_p is wavelength at radial resonance frequency of disk piezoid in diaphragm, filling compound, deflector, and piezoid, respectively; ρ_d and ρ_c are densities of diaphragm and compound, respectively. EFFECT: facilitated check-up of gas and liquid level in enclosed vessels. 3 cl, 2 dwg