抄録
Accelerometers are typical examples of piezoelectric elements applying the piezoelectric effect that causes a charge production by applying inertia force on them. Despite the advances of piezoelectric devices and materials in the field of electronics engineering, of decisive importance for piezoelectric effect has not been correctly understood in some branch of mechanical engineering. Especially ,accelerometer is wrongly misused for the unfit purpose,"Innocent misapprehension of jerk, the rate at which acceleration changes". The nature of the piezoelectric effect is closely related to the occurrence of electric charge and a voltage at electrodes. The best-known application is the piezoelectric accelerometer, but direct detection of acceleration variations in the form of jerk is the most unreasonable sensor application. The author will discuss the principles of piezoelectric element using the equivalent of electric circuit from a view point of designing machine elements.
