Lock with emergency actuator

A lock for closing a door with respect to a frame, comprising a lock body and a striker, wherein the lock body is mounted on the door and the striker is mounted on the frame, or vice versa, wherein the lock body comprises:

• a catch element mounted so as to rotate between a striker keep position and a striker release position;
• elastic means suitable for driving the catch element from the striker keep position to the striker release position;
• a lever suitable for moving between a closing position in which the lever maintains the catch element in the striker keep position and an opening position in which the lever is disengaged from the catch element;
• a service actuator suitable for applying a service actuator force on the lever to bring the lever from the closing position to the opening position;
• wherein the lock body further comprises a shape memory alloy actuator with a shape memory alloy wire suitable for applying a shape memory alloy wire force directly on the lever so as to bring the lever from the closing position to the opening position, wherein the shape memory alloy actuator is configured to apply a shape memory alloy wire force higher than 100 N,
• wherein the shape memory alloy actuator comprises a detent for allowing the shape memory alloy wire force to be applied on the lever only when the shape memory alloy wire force exceeds a predetermined threshold value as effect of a fracture or sudden deformation of said detent, and
• wherein the detent comprises a hook designed to break in an emergency condition, thus the detent being irreversibly damaged in an emergency condition.