Multilayer-type piezoelectric actuator

摘要

A multilayer-type piezoelectric actuator having a multilayer piezoelectric unit which is capable of enduring the extension of contraction thereof to prevent the disconnection of external electrodes. The multilayer piezoelectric unit (2) includes a plurality of piezoelectric plates (21) of a piezoelectric material and a plurality of internal electrodes (22) of a conductive material arranged in alternate layers. The external electrodes (3) are arranged on the side surfaces (23), respectively, of the multilayer piezoelectric unit (2) and electrically connected to a plurality of the internal electrodes (22). The external electrodes (3) are each configured of an electrode base (31) arranged in contact with a corresponding side surface (23) of the multilayer piezoelectric unit (2), a tabular metal net conductor (32) arranged on the electrode base (31), and a plurality of conductive adhesives (33) for partially bonding the electrode base (31) and the tabular metal net conductor (32). Adjacent ones of the conductive adhesives (33) have a portion mutually superposed in the direction parallel to the piezoelectric plates (21).