Patent ID: 7851979
Filing Date: 2010-12-14
Classification: H01L,Y10T

Abstract:
1. A piezoceramic multilayer actuator comprising a piezo-stack, which has a plurality N of piezo layers having at least one expandable outer electrode which provides at least two current paths between a supply potential connecting area of the outer electrode and a respective inner electrode of the piezo-stack with which the outer electrode makes contact, wherein the piezo-stack has a plurality N of first inner electrodes and a plurality N of second inner electrodes, with a piezo layer being arranged between a first inner electrode and a second inner electrode and the plurality N of first inner electrodes being electrically coupled to a first outer electrode and the plurality N of second inner electrodes to a second outer electrode, wherein, the first outer electrode and the second outer electrode essentially span the piezo-stack, with the first outer electrode being connected to a first metallization, which electrically contacts the N first inner electrodes and the second outer electrode to a second metallization, which electrically contacts the N second inner electrodes, wherein the outer electrode comprises: the supply potential connecting area; a plurality of N fingers, which are electronically contacted parallel to the metallization in the area of an inner electrode in each case; a plurality N of contact links arranged in parallel in the axial direction of the piezo-stack, which span the piezo-stack in the circumferential direction and feature a first distance to the piezo-stack, with two adjacent contact links in each case being separated from each other by means of at least one slot arranged in the circumferential direction in order to increase the expansion capacity of the outer electrode and being connected to each other by means of at least one bridge section arranged in the longitudinal direction of the piezo-stack for conveying the current; a plurality N of connecting sections arranged in the transverse direction of the piezo-stack, with one connecting section in each case electrically connecting one specific finger to the corresponding contact link.