Electromechanical actuator assembly with mechanical override feature

An aircraft passenger seat assembly, comprising:

• a seat bottom;
• a seat back;
• and
• an electromechanical actuator assembly (EMA) configured to adjust the seat back between an upright sitting position and a reclined position, the EMA comprising:
• a housing;
• an electric motor including a rotating drive shaft;
• an epicyclic gearbox disposed in the housing and rotationally coupled to the rotating drive shaft, the epicyclic gearbox including a first ring gear and a second ring gear;
• and
• a mechanical override mechanism, comprising:
• a first spring-loaded shoot bolt disposed in the housing and coupled to the first ring gear;
• a second spring-loaded shoot bolt disposed in the housing and coupled to the first ring gear;
• a displaceable plate disposed in housing and engaging one end of each of the first and second spring-loaded shoot bolts;
• and
• a manual release pin coupled to the displaceable plate;
• wherein:
• during a powered condition of the EMA, the manual release pin is positioned in a first position such that each of the first and second spring-loaded shoot bolts are coupled to the second ring gear such that the first and second spring-loaded shoot bolts couple the first and second ring gears;
• and
• during a power loss condition of the EMA, the manual release pin is moveable to a second position in which the displaceable plate displaces toward the first ring gear to simultaneously displace the first and second spring-loaded shoot bolts toward the first ring gear to decouple the first and second ring gears to permit the second ring gear to be rotated manually relative to the first ring gear.

A mechanism for releasing a coupling between a first ring gear and a second ring gear, the mechanism comprising:

• at least one spring-loaded shoot bolt including:
• a spring cup coupled to the first ring gear;
• a shoot bolt housing coupled to the second ring gear;
• and
• a compression spring having a first end engaged in the spring cup and a second end engaged in the shoot bolt housing;
• a displaceable plate engaging an end of the shoot bolt housing opposite the spring cup;
• and
• a displaceable pin mounted to the displaceable plate;
• wherein movement of the displaceable pin in a direction of the first ring gear causes the displaceable plate to displace the shoot bolt housing thereby causing the compression spring to compress and the shoot bolt housing to move out of coupling with the second gear thereby allowing the second gear to rotate relative to the first gear.