Piezo sensors are used to convert mechanical movements, such as force, acceleration or pressure, into electric signals.
Apart from classical vibration recorders to detect imbalances of rotating machine parts or in crash detectors in the automotive industry, they are being used more and more in ultrasonic level measurement and flow rate measurement applications.
There, for example, the propagation time of the reflected echo of an ultrasonic wave is evaluated. Flow rate measurements are based on propagation time measurements or on the Doppler effect (measurement of phase difference). Further typical applications of “soft“ piezo ceramics are to be found in object identification and surveillance (e. g. surveillance sensors for cars, glass tampering detectors, etc.), sound transmitters (buzzers) and sound receivers (microphones), to their use in the sound pickups of musical instruments.