LAMINATED PIEZOELECTRIC ELEMENT, INJECTION DEVICE HAVING THE ELEMENT, AND FUEL INJECTION SYSTEM

摘要

Provided is a laminated piezoelectric element in which the amount of the positional displacement can be suppressed even when continuous driving is performed for a long time under high field and high pressure, and which may have a good durability. The laminated piezoelectric element comprises a laminated structure formed by alternately laminating piezoelectric layers and metal layers. Each of the metal layers comprises an inner electrode and a low rigid metal layer having the rigidity lower than that of the piezoelectric layer and the inner electrode. The low rigid metal layer includes metal parts separated from each other with gaps therebetween and a covering layer for covering at least a part of the side surface of each metal part.