Views:22 Author:Site Editor Publish Time: 2019-09-05 Origin:Site
Structure of piezoelectric diaphragm
The piezoelectric sound element must have a piezoelectric diaphragm.
This is a simple structure in which a piezoelectric ceramic adheres to brass or nickel alloy metal plate.
Mechanism of producing sound for piezo diaphragms
When a voltage is applied to the piezoelectric ceramic, it extends in its plane. When a voltage is applied to the piezoelectric diaphragm, since the metal plate is not stretched, it is bent as shown in (a). When the polarity of the applied voltage is reversed, the piezoelectric ceramic shrinks and the metal plate is bent toward the opposite side as shown in (b).
When the direction of the applied voltage alternates, the states of (a) and (b) are repeated, and as shown in (c), sound waves are generated in the air.