Kyocera Corporation

Shinsaku Satoi

Masahiro Inagaki

Katsuhiko Hanada

A piezoelectric actuator includes: a piezoelectric element; and a case including a base body and a tubular body, the case being configured to receive the piezoelectric element. The base body includes a bottom plate portion and an annular projection disposed upright on the bottom plate portion. The annular projection includes an upper-side first region having a relatively small outside diameter and a lower-side second region having a relatively large outside diameter, and includes a stepped outer surface defined by an outer surface of the first region and an outer surface of the second region that are connected with each other. The first region is inserted inside the tubular body, an end face of the tubular body abuts on an upper end of the second region, and the tubular body and the second region is joined to each other.

Piezoelectric actuator

A multi-layer piezoelectric element includes a stacked body including piezoelectric layers and internal electrode layers, which are alternately stacked; an external electrode layer attached to a side surface of the stacked body, the external electrode layer being elongated in a stacking direction of the stacked body and electrically connected with ends of the internal electrode layers which are exposed on the side surface; and an external electrode plate bonded to the external electrode layer therealong by an electrically conducting bonding material. The external electrode plate is provided with slits which extend from opposite long sides toward a center thereof in such a manner that tips of the respective slits overlap each other when viewed in the stacking direction of the stacked body, and a portion thereof where the tips of the respective slits overlap each other is provided with a hole extending along an extension direction of the slit.

Growing community of inventors

Kirishima, Japan

Shinsaku Satoi