MULTIPLE-USE PIEZOELECTRIC FILM TRANSDUCER FOR MEASUREMENT OF DYNAMIC STRAINS Russian patent published in 2000 - IPC

FIELD: dynamic strain measuring facilities measuring the dynamic strained condition of engineering constructions. SUBSTANCE: the principle of transducer operation is based on direct piezoelectric effect. The transducer body is made of plastic material with a low longitudinal modulus of elasticity. The body material and dimensions are so selected that the stiffness of the adhesive layer would be considerably higher than that of the transducer body base. The base has a rib facing inside the body, oriented normally to the base bearing surface and having a constant thickness. A piezoelectric element with electrodes is applied onto the rib vertical plane by the adhesion method. The transducer has a standard microconnector for connection to a preamplifier, compatible with traditional vibration - metering equipment and can measure very low values of dynamic strains from 10^-6μm/m. The transducer may be used many times with a stability of the amplitude-frequency response within 3 to 9% and phase-frequency response within 0.1 to 0.3 deg. The transducer is attached to the object with the aid of adhesive. EFFECT: enhanced accuracy of measurements and reduced lateral sensitivity and sensitivity to acoustic pressure and electromagnetic fields. 2 dwg