PIEZOELECTRIC ACTUATOR AND VALVE

To easily realize a configuration capable of generating a larger displacement or force with a lower applied voltage.SOLUTION: A piezoelectric actuator has a configuration in which a first piezoelectric element 10 is disposed on a shim plate 40 and a second piezoelectric element 20 is disposed on the first piezoelectric element 10. The first piezoelectric element 10 has a first polarity on the first electrode 14 side and a second polarity on the second electrode 16 side, and the second piezoelectric element 20 has a second polarity on the third electrode 24 side, and a first polarity on the four electrode 26 side. In the first piezoelectric element 10 and the second piezoelectric element 20, the second electrode 16 and the third electrode 24 are joined to each other, and are electrically connected to each other, and the first electrode 14 is joined to one main surface 41 of the shim plate 40.SELECTED DRAWING: Figure 3 【課題】より低い印加電圧で、より大きな変位又は力を生じさせ得る構成を、簡易に実現する。【解決手段】圧電アクチュエータは、シム板４０上に第１圧電素子１０が配置され、第１圧電素子１０上に第２圧電素子２０が配置された構成をなす。第１圧電素子１０は、第１電極１４側が第１極性とされ、第２電極１６側が第２極性とされており、第２圧電素子２０は、第３電極２４側が第２極性とされ、第４電極２６側が第１極性とされている。第１圧電素子１０及び第２圧電素子２０において、第２電極１６と第３電極２４とが互いに接合され、且つ、互いに電気的に接続されており、シム板４０の一方の主面４１に第１電極１４が接合されている。【選択図】図３