公开(公告)号：US11730060B2

公开(公告)日：2023-08-15

申请号：US16941705

申请日：2020-07-29

Applicant: Murata Manufacturing Co., Ltd.

Inventor： Yoshiyuki Yamakawa ,  Seishiro Goto ,  Shinichiro Kawada ,  Shigetoshi Hayashi ,  Akio Fujita ,  Yusuke Nakamura

IPC: H10N30/853 ,  H10N30/50 ,  H10N30/87

CPC classification number: H10N30/8536 ,  H10N30/50 ,  H10N30/872

Abstract: A piezoelectric actuator that includes a multilayer body, a low-potential outer electrode, and a high-potential outer electrode. The multilayer body includes multiple alternately stacked piezoelectric ceramic layers and planar electrodes. The planar electrodes include low-potential planar electrodes electrically connected to the low-potential outer electrode and high-potential planar electrodes electrically connected to the high-potential outer electrode. The planar electrode positioned most outwardly on the side of a first main surface of the multilayer body is a low-potential planar electrode. The inner surface of this low-potential planar electrode contacts the − side of polarization in an active region, and the outer surface of this low-potential planar electrode is exposed on an outside of the multilayer body. On the side of a second main surface of the multilayer body, a high-potential planar electrode is not exposed on the outside of the multilayer body.