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 multilayer piezoelectric element includes a piezoelectric body containing a piezoelectric ceramic material, a first electrode, and a second electrode. The piezoelectric body includes a first main surface and a second main surface opposing each other. The first electrode includes an external electrode formed on the first main surface. The second electrode includes an internal electrode formed inside the piezoelectric body to oppose the external electrode. The piezoelectric body includes an active region between the external electrode and the internal electrode, and includes an inactive region opposite to the active region with the internal electrode interposed therebetween. A stress received by the piezoelectric body from the external electrode is larger than a stress received by the piezoelectric body from the internal electrode. A polarization direction of the active region is a direction directed from the external electrode to the internal electrode.

Abstract: A piezoelectric element includes a piezoelectric body, a first electrode, a second electrode, a third electrode, and a first through hole conductor. The piezoelectric body includes first and second main surfaces opposing each other, and first and second end surfaces opposing each other. The first electrode is disposed on the first main surface. The second electrode is disposed apart from the first electrode on the first main surface. The third electrode is disposed in the piezoelectric body to oppose the first electrode. The first through hole conductor is connected to the second and third electrodes. The piezoelectric body includes an active region and an inactive region. The active region includes a region from the first electrode to the third electrode. The inactive region includes a region from the third electrode to the second main surface.

Abstract: In object to provide a unit of piezoelectric element having a preferable bending strength and preferably used as a part of a driving unit, a unit of piezoelectric element comprising: a multilayer piezoelectric element, having internal electrodes laminated having a piezoelectric body layer in-between and a pair of external electrodes formed on side surfaces extending along laminating direction and electrically connected to the internal electrodes, a wiring part connected to the external electrodes via a solder part, wherein a solder is solidified, a resin part, joining one end surface in the laminating direction of the multilayer piezoelectric element and a mounting surface of a connection member placed to face the one end surface, wherein the resin part is continuous from the one end surface and the mounting surface to the solder part; and the resin part covers the solder part, is provided.

Abstract: A piezoelectric element includes a piezoelectric body, an external electrode, and an internal electrode. The piezoelectric body includes first and second main surfaces opposing each other. The external electrode is disposed on the first main surface and has a first polarity. The internal electrode is disposed in the piezoelectric body to oppose the external electrode in a direction in which the first main surface and the second main surface oppose each other and has a second polarity different from the first polarity. A region from the internal electrode to the external electrode in the piezoelectric body is a polarizing region, and a region from the internal electrode to the second main surface in the piezoelectric body is a non-polarizing region.

Abstract: A piezoelectric element includes a piezoelectric body, a first electrode, a second electrode, a third electrode, and a first through hole conductor. The piezoelectric body includes first and second main surfaces opposing each other, and first and second end surfaces opposing each other. The first electrode is disposed on the first main surface. The second electrode is disposed apart from the first electrode on the first main surface. The third electrode is disposed in the piezoelectric body to oppose the first electrode. The first through hole conductor is connected to the second and third electrodes. The piezoelectric body includes an active region and an inactive region. The active region includes a region from the first electrode to the third electrode. The inactive region includes a region from the third electrode to the second main surface.

Abstract: In object to provide a unit of piezoelectric element having a preferable bending strength and preferably used as a part of a driving unit, a unit of piezoelectric element comprising: a multilayer piezoelectric element, having internal electrodes laminated having a piezoelectric body layer in-between and a pair of external electrodes formed on side surfaces extending along laminating direction and electrically connected to the internal electrodes, a wiring part connected to the external electrodes via a solder part, wherein a solder is solidified, a resin part, joining one end surface in the laminating direction of the multilayer piezoelectric element and a mounting surface of a connection member placed to face the one end surface, wherein the resin part is continuous from the one end surface and the mounting surface to the solder part; and the resin part covers the solder part, is provided.

Abstract: In object to provide a unit of piezoelectric element having a preferable bending strength and preferably used as a part of a driving unit, a unit of piezoelectric element comprising: a multilayer piezoelectric element, having internal electrodes laminated having a piezoelectric body layer in-between and a pair of external electrodes formed on side surfaces extending along laminating direction and electrically connected to the internal electrodes, a wiring part connected to the external electrodes via a solder part, wherein a solder is solidified, a resin part, joining one end surface in the laminating direction of the multilayer piezoelectric element and a mounting surface of a connection member placed to face the one end surface, wherein the resin part is continuous from the one end surface and the mounting surface to the solder part; and the resin part covers the solder part, is provided.

Abstract: A piezoelectric element includes a piezoelectric body, an external electrode, and an internal electrode. The piezoelectric body includes first and second main surfaces opposing each other. The external electrode is disposed on the first main surface and has a first polarity. The internal electrode is disposed in the piezoelectric body to oppose the external electrode in a direction in which the first main surface and the second main surface oppose each other and has a second polarity different from the first polarity. A region from the internal electrode to the external electrode in the piezoelectric body is a polarizing region, and a region from the internal electrode to the second main surface in the piezoelectric body is a non-polarizing region.

Abstract: In object to provide a unit of piezoelectric element having a preferable bending strength and preferably used as a part of a driving unit, a unit of piezoelectric element comprising: a multilayer piezoelectric element, having internal electrodes laminated having a piezoelectric body layer in-between and a pair of external electrodes formed on side surfaces extending along laminating direction and electrically connected to the internal electrodes, a wiring part connected to the external electrodes via a solder part, wherein a solder is solidified, a resin part, joining one end surface in the laminating direction of the multilayer piezoelectric element and a mounting surface of a connection member placed to face the one end surface, wherein the resin part is continuous from the one end surface and the mounting surface to the solder part; and the resin part covers the solder part, is provided.