Patent ID: 7851978

Claim:
A piezo actuator with multilayer encapsulation, or a multilayer actuator, such that the piezo actuator is externally protected without an additional solid casing-type enveloping structure, comprising: a piezo actuator, an electrically insulating elastic layer on a surface of the piezo actuator, said surface running parallel with the longitudinal or stacking direction of the piezo actuator, a metallic layer on the electrically insulating elastic layer, said metallic layer covering the electrically insulating elastic layer in a planar manner, a further electrically insulating elastic layer on the metallic layer, and a further metallic layer on the further electrically insulating elastic layer, wherein the electrically insulating layer, the further electrically insulating elastic layer and the further metallic layer are adapted in terms of material and thickness, such that a gradual property transition from the piezo actuator to the further metallic layer is created, thereby ensuring compatible material behavior of encapsulation and piezo actuator.