Electric jack comprising stress-limiting means and space launcher comprising a nozzle supported by such a jack

An engine for a space launcher, including

• at least one jet nozzle, and
• at least one electromechanical actuator for moving a first element with respect to a second element, said at least one electromechanical actuator comprising:
• a movable member (14) provided with connecting means for being attached to said first element,
• a frame provided with attaching means for being attached to said second element, wherein said movable member is translationally movable with respect to said frame,
• a driving unit which drives the movable member in translation, and
• at least one mechanical energy absorbing-dissipating structure located on a strain path between said first element and said frame of the actuator, said at least one mechanical energy absorbing-dissipating structure comprising:
• a deformable chamber containing at least one porous capillary matrix having open pores and an associated liquid having a wetting angle higher than 90 degrees relative to said matrix and selected such that at least part of said liquid penetrates the pores of said matrix, when an external mechanical pressure applied to the chamber is equal to or higher than a first pressure level PI, and is spontaneously rejected off the pores of said matrix by capillary action, when said external mechanical pressure applied to the chamber is lower than a second pressure level P2 which is lower than said first pressure level P1 such that the at least one energy absorbing-dissipating structure limits a level of strains which may be transmitted to the frame of the electromechanical actuator by the first element via the movable member of the electromechanical actuator,
• wherein said movable member is in said strain path and said external mechanical pressure applied to said deformable chamber is a sum of forces applied to said movable member by said driving unit and an external strain applied to said first element.

A space launcher, comprising at least one engine including:

• at least one jet nozzle, and
• at least one electromechanical actuator for moving a first element with respect to a second element, the at least one electromechanical actuator comprising:
• a movable member provided with connecting means for being attached to said first element,
• a frame provided with attaching means for being attached to said second element, wherein said movable member is translationally movable with respect to said frame,
• a driving unit which drives the movable member in translation, wherein said actuator;
• and
• at least one mechanical energy absorbing-dissipating structure located on a strain path between said first element and said frame of the actuator, the at least one mechanical energy absorbing-dissipating structure comprising
• a deformable chamber containing at least one porous capillary matrix having open pores and an associated liquid having a wetting angle higher than 90 degrees relative to said matrix and selected such that at least part of said liquid penetrates the pores of said matrix, when an external mechanical pressure applied to the chamber is equal to or higher than a first pressure level PI, and is spontaneously rejected off the pores of said matrix by capillary action, when said external mechanical pressure applied to the chamber is lower than a second pressure level P2 which is lower than said first pressure level P1 such that the at least one energy absorbing-dissipating structure limits a level of strains which may be transmitted to the frame of the electromechanical actuator by the first element via the movable member of the electromechanical actuator,
• wherein said movable member is in said strain path and said external mechanical pressure applied to said deformable chamber is a sum of forces applied to said movable member by said driving unit and an external strain applied to said first element.