Patent attributes
A piezoelectric expansion actuator for d33 piezoelements, which allows vibrations in structures to be suppressed. An expansion actuator (1) includes a piezoelectric stack (2), which consists of d33 piezoelectric elements and is arranged between output elements (4), which are attached to the surface of the structure (7). The invention applies to a piezoelectric extension actuator, which is used to control vibrations in structures. Alternatively, in order to damp vibrations between the main gearbox of a helicopter rotor and the cellular structure of the cockpit, a power application point of the output element (18, 19, 180, 190; 35, 36) is arranged at a distance from the corresponding end plate of the piezoelectric stack (22, 220; 31, 32, 33) in the axial direction (X).