LAMINATED PIEZOELECTRIC ELEMENT AND MANUFACTURING METHOD THEREFOR

PROBLEM TO BE SOLVED: To provide a laminated piezoelectric element which enhances rigidity and dimensional accuracy of a drive plane, using simple structure. SOLUTION: A groove part 20, reaching from an upper plane to a lower plane, is formed in a part relevant to a ridge part in a lamination direction of laminate 10, and as a conductor part 21 for electrically connecting an internal electrode 12 to an external electrode 13 every layer of the internal electrode is provided in the internal wall of the groove part 20, a stress concentration at the time of operating is mitigated to restrict a generation of cracks, etc., thereby preventing a breakdown. Furthermore, a connection failure of the conductor part 21 is prevented, and since it is unnecessary to provide the external electrode on a drive plane 14, irrespective of a method for forming the external electrode, it is possible to enhance rigidity and dimensional accuracy of the drive plane 14 using a simple structure. Furthermore, as it is unnecessary to form a groove on a side plane of the laminate 10, bending strength is enhanced to prevent breakdown at operating, and since a pair of external electrodes 13 are not close to each other, it is possible to prevent electrical short- circuiting, and to increase an active part area, to increase a displacement to enhance an extension ratio.