Multi-Layer Piezoelectric Element, Ejection Apparatus Using the Same and Fuel Ejection System

Abstract

To provide a multi-layer piezoelectric element which is easy to be fabricated and which exhibits excellent durability, even when it is driven continuously for a long time under high electric field and high pressure. The multi-layer piezoelectric element comprising a stacked body wherein a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately one on another and it is driven by applying a voltage to adjacent and opposing metal layers, wherein an average grain size of the piezoelectric crystal grains in a side face of the stacked body is larger than an average grain size of the piezoelectric crystal grains in the piezoelectric layer which is sandwiched between the adjacent and opposing metal layers.

Dependencies are inferred from the claim text.