Piezoelectric actuator for use in rotor of piezoelectric rotary engine, has cylindrical surface partially made of piezoelectric material surrounding axis, and protuberance turned around axis

摘要

The actuator (10) has a cylindrical surface partially made of piezoelectric material (9) surrounding an axis (X), where the cylindrical surface is a surface of a revolution cylinder (11). Two external electrodes (21, 22) and an internal electrode (23) are induced on the cylindrical surface by piezoelectric effect, where a polarization vector (P) of the piezoelectric material is radial. A protuberance is turned around the axis. One of the electrodes is located in an external periphery (12) of the actuator. The other electrode is located in an internal periphery (13) of the actuator. An independent claim is also included for a piezoelectric rotary engine.