Sfim Industries

Barthelemy Groult

Jean-Claude Charrier

A piezoelectric or electrostrictive actuator, comprising a plurality of stages of piezoelectric or electrostrictive active blocks distributed so as to form a tubular structure, the polarization of the active blocks alternating from one stage to the next, separation elements separating the unit active blocks of any one stage in pairs, said elements being superposed on one another in the height direction of the structure, being suitable for sliding over one another, and being of stiffness greater than that of the unit active blocks, a separation element extending over the height of two stages of active blocks, the separation elements on either side of a given unit active block extending respectively through both stages on either side of said unit active block, electrode-forming means enabling voltages of alternating sign to be applied to the various stacks of active blocks, and wherein a separation element is constituted by two bonded-together slabs each belonging to a different stage, the slabs of any one stage alternating between slabs that are integral with a prestress structure which extends inside said stage, and slabs that are bonded to slabs of the preceding stage which are integral with the prestress structure of said other stage.

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Paris, France

Barthelemy Groult