| US 7,501,742 B2 | ||
| Mechanical actuator comprising an active linear piston | ||
| Oscar D'Almeida, Boulogne Billancourt (France); Mathias Woydt, Berlin (Germany); and Jean-Thierry Audren, Saint Remy les Chevreuses (France) | ||
| Assigned to Sagem Defense Securite, Paris (France) | ||
| Filed on May 30, 2006, as Appl. No. 11/443,662. | ||
| Claims priority of application No. 05 05475 (FR), filed on May 31, 2005. | ||
| Prior Publication US 2007/0114886 A1, May 24, 2007 | ||
| Int. Cl. H01L 41/08 (2006.01) | ||
| U.S. Cl. 310—328 | 14 Claims |
| 1. An actuator comprising a sliding sleeve and a piston having a plurality of sections made of an active material, wherein
control means are capable of acting on said materials so that the sections block with respect to the sliding sleeve or extend
longitudinally according to a sequence which leads to the axial movement of the piston in the sliding sleeve, wherein the
sliding sleeve and the piston have at their interface at least one pair of friction layers,
wherein at least one friction layer is a material selected from the following:
an oxide of a Ti and Cr alloy, where the oxide is in the form of a stabilised solid solution and/or in the form of a non-stoechiometric
solid solution;
a zirconium matrix stabilised by Sc2O3 and/or Al2O3 and/or Cr2O3;
a zirconium oxide in tetragonal phase stabilised by Y2O3, where the size of the oxide grains is less than 100 nm; and/or
any possible combination of these materials.
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