Patent ID: 7449077
Filing Date: 2008-11-11
Classification: H01L

Abstract:
1. A method for the production of a monolithic multilayer actuator a comprising a piezoceramic or electrostrictive material, with the actuator being formed as a stack arrangement in a quasi mechanical series connection of a plurality of piezoplates by sintering of green foils, existing inner electrodes in the plate stack being routed to at least two opposite outer surfaces of the stack, where they are connected in parallel by a basic metallic coating as well as an external contact of respective electrode groups, wherein specific microdisturbances are incorporated in the actuator structure along the longitudinal axis of the stack essentially parallel and spaced from the inner electrodes in the area of the at least two opposite outer surfaces to which the inner electrodes known per se are brought out, which at the earliest during polarisation of the actuator are subject to a pregiven, limited, stress-reducing growth into the interior of the actuator; wherein the microdisturbances permit transmission of pressure, but not tensile stress, between the piezoplates; and wherein additionally the external contact is formed elongation-resistant or elastic at least in the area of the microdisturbances.