Tdk Corporation

Katsuya Inaba

Satoshi Sasaki

Kazushi Tachimoto

Yoshiki Ohta

Yoko Abe

Masayoshi Inoue

Yoshiaki Ohta

Yasuyuki Satoh

Katsumi Yamauchi

Takahiro Kezuka

Rin Sato

Yuzo Komatsu

A piezoelectric actuator () includes: a piezoelectric element (); and a first frictional portion () and a second frictional portion () that are disposed on one principal surface () of the piezoelectric element (). The first frictional portion () is disposed at a position other than the antinodes of the piezoelectric element () at which a distance from one of the end surfaces () is less than &#x2153; L, where L represents a length in the longitudinal direction of the piezoelectric element (). The second frictional portion () is disposed at a position other than the antinodes of the piezoelectric element () at which a distance from the other of the end surfaces () is less than &#x2153; L.

Piezoelectric actuator having separate frictional portions

In a piezoelectric element, internal stress generated in an inactive portion at the time of sintering when a piezoelectric element is fabricated or stress applied from the outside to the inactive portion is absorbed by a recess of a lower surface of a first through hole conductor and a recess of an upper surface of a second through hole conductor. Accordingly, for example, deformation, rupture, or the like of the through hole conductor is prevented, and conduction failure or disconnection of an electrode layer or a through hole conductor is prevented. Further, in the inactive portion, since a protrusion of the piezoelectric layer enters the recess of the through hole conductor, a holding force of the piezoelectric layer with respect to the through hole conductor increases, and deformation of the through hole conductor is prevented or obstructed.

Piezoelectric element

Growing community of inventors

Tokyo, Japan

Katsuya Inaba