to the sheath 3 of a flexible cable actuator device on the sheath 3 is secured a bushing 102 intended to come into contact against a fixed stop 103 being part of the structure 104 of the locking device of the hatch door the cooperating action of the bushing 102 integral with the sheath 3 and of the end stop 103 prevents a movement of the sheath 3 in an opposite direction to the one of activation inside the sheath 3 is fitted a flexible cable 2 of memory shape material let it be clearly understood that it is also possible to realize the device with a rigid cable instead of a flexible one which is secured at an end 2 a to a cylindrical body 5 which is in turn connected through an opening 105 made in the wall of the casing of the lock 104 to the controlled mechanism of the lock not illustrated means of electricity supply not illustrated are also foreseen to apply an electric tension to the two opposite ends of the shape memory cable 2 with the aim to cause it to shorten when the actuator is operated manually acting on the ring 100 the mechanical traction is transmitted through the sheath 3 which is shifting towards the right with reference to fig1 causing a distancing of the bushing 102 from the fixed stop 103 the movement of the sheath 3 causes a corresponding movement of.