Abstract: A piezoelectric element includes a piezoelectric body and first, second, third, and fourth electrode layers disposed in the piezoelectric body. Each of the first, second, third, and fourth electrode layers includes a pair of first electrodes and a pair of second electrodes. The first and second electrodes included in the first electrode layer oppose the second and first electrodes included in the second electrode layer, respectively, with a part of the piezoelectric body. The first and second electrodes included in the second electrode layer oppose the first and second electrodes included in the third electrode layer, respectively, with a part of the piezoelectric body. The first and second electrodes included in the third electrode layer oppose the second and first electrodes included in the fourth electrode layer, respectively, with a part of the piezoelectric body.

Abstract: A piezoelectric actuator includes a piezoelectric element having a rectangular shape, a first supporter, and a second supporter. The piezoelectric element includes a pair of main surfaces opposing each other, a first end surface and a second end surface opposing each other in a long side direction of the pair of main surfaces, and a first side surface and a second side surface opposing each other in a short side direction of the pair of main surfaces. The first supporter is provided to be movable according to deformation of the first end surface. The second supporter is provided to be movable according to deformation of the first side surface. The first supporter includes an opposing portion and a protruding portion. The opposing portion opposes the second supporter in the long side direction. The protruding portion protrudes from the opposing portion and abuts on the second supporter.

Abstract: A laminated piezoelectric element has excellent suppression effect on characteristics deterioration caused by a pyroelectric effect. Inside an element main body are a first internal electrode, a piezoelectric layer, and a second internal electrode that has different polarity from the first internal electrode, which are repeatedly layered a plurality of times along the lamination direction. A first external electrode is formed on a first side surface of the element main body. A second external electrode is formed on a second side surface of the element main body. A resistance layer connected to the internal electrodes is formed in at least part of a third side surface of the element main body in which the internal electrodes are exposed. An insulating layer is formed on a third side of the element main body so as to cover the resistance layer.

Abstract: A piezoelectric element includes a laminate, a plurality of internal electrodes, and a plurality of external electrodes. The laminate includes a plurality of piezoelectric layers that is laminated. The laminate includes a pair of main faces facing away from each other in a laminating direction of the plurality of piezoelectric layers, a pair of end faces facing away from each other in a first direction crossing the laminating direction, and a pair of side faces facing away from each other in a second direction crossing the laminating direction and the first direction. The plurality of internal electrodes is disposed in the laminate to be laminated in the laminating direction. Each of the pair of main faces, the pair of end faces, and the pair of side faces is a polished surface that is polished. Each ridge portion of the laminate has a rounded chamfered shape.

Abstract: A piezoelectric element includes a laminate and a first internal electrode. The laminate includes a pair of main faces, a pair of end faces, and a pair of side faces. The first internal electrode includes four electrode portions and a connector. The four electrode portions include a first pair of electrode portions and a second pair of electrode portions. The connector connects the first pair of electrode portions. The connector is spaced apart from each of the second pair of electrode portions by a first distance. Each of the four electrode portions includes a main electrode part. The main electrode part is spaced apart from the pair of end faces by a second distance. The main electrode part is spaced apart from the pair of side faces by a third distance. The first distance is longer than each of the second distance and the third distance.

Abstract: A piezoelectric actuator (1) includes: a piezoelectric element (3); and a first frictional portion (10) and a second frictional portion (12) that are disposed on one principal surface (2d) of the piezoelectric element (3). The first frictional portion (10) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from one of the end surfaces (2a) is less than ? L, where L represents a length in the longitudinal direction of the piezoelectric element (3). The second frictional portion (12) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from the other of the end surfaces (2b) is less than ? L.

Abstract: A piezoelectric actuator (1) includes: a piezoelectric element (3); and a first frictional portion (10) and a second frictional portion (12) that are disposed on one principal surface (2d) of the piezoelectric element (3). The first frictional portion (10) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from one of the end surfaces (2a) is less than ? L, where L represents a length in the longitudinal direction of the piezoelectric element (3). The second frictional portion (12) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from the other of the end surfaces (2b) is less than ? L.

Abstract: A multilayer piezoelectric device comprises a multilayer body and first and second outer electrodes. The multilayer body has base, first and second driving parts, and non-driving part. The driving parts and non-driving part extend from the base along stacking direction. The first driving part is closer to the non-driving part than the second driving part. Each driving part has first and second inner electrodes opposing each other in stacking direction. The base has a third inner electrode extending along a plane orthogonal to the stacking direction. The first outer electrode is connected to the first inner electrode. The second outer electrode is connected to the second and third inner electrodes. In the stacking direction, the overlap area of the third and second inner electrode of the first driving part is greater than the overlap area of the third and second inner electrode of the second driving part.

Abstract: A multilayer piezoelectric device comprises a multilayer body and first and second outer electrodes. The multilayer body has base, first and second driving parts, and non-driving part. The driving parts and non-driving part extend from the base along stacking direction. The first driving part is closer to the non-driving part than the second driving part. Each driving part has first and second inner electrodes opposing each other in stacking direction. The base has a third inner electrode extending along a plane orthogonal to the stacking direction. The first outer electrode is connected to the first inner electrode. The second outer electrode is connected to the second and third inner electrodes. In the stacking direction, the overlap area of the third and second inner electrode of the first driving part is greater than the overlap area of the third and second inner electrode of the second driving part.