Piezoelectric accelerometers based on ferro electric ceramics first surfaced in the late 40's as means of collecting data on the dynamic behaviour of airframes and a variety of military and avionic hardware, supplanting the heavier, less robust velocity transducer. Early devices comprised a piezoceramic disc sandwiched between a reaction mass and a cylindrical base (the means of attachment to the test object), and this manner of construction features in several manufacturers products today.
However the art has moved on; disadvantages inherent in this compression disc design, namely high strain sensitivity and cross axis error, preclude their use for many applications and have directly led to several innovations whereby the acceleration/charge conversion is accomplished by means of a shear couple applied to a piezoceramic plate or tube.
Specifically, our KONIC shear design (UK pat 1507251), comprising a truncated hollow piezoceramic cone, spigot, and concentric reaction mass, provides virtual isolation of the sensing element from mounting induced strain, with the further benefit of minimal cross axis error deriving from its radial symmetry.
The DJB range of accelerometers provides both Charge Output and Votage Output IEPE Accelerometers including the worlds smallest stainless steel accelerometers (A/28/E and A/128/V), modal clip mounted triaxial accelerometers (AT/13), and IEPE Accelerometers capable of operating in extreme temperatures ranging from 185°C to 900°C. DJB's wide range of accelerometers are suitable for almost any vibration measurement application requiring a high degree of accuracy, in a potentially hostile environment.