An apparatus for actuating a rocking motion of a movable component comprises a adjustable length actuator (14,34), a lever (15,40) whose angular position is controlled by the actuator and a force transfer element (12；48,49) attached to the movable component, and wherein the lever (15) is provided with a pair of oppositely placed pawls (20,21), the pawls being shaped so as to interact with the force transfer element for respectively actuating movement of the component in one of two opposite directions, when the lever exits a neutral positional range in which range any interaction between both pawls and the force transfer element is prohibited. The neutral range may be defined by a support plate (25) positioned, shaped and dimensioned so as to prohibit interaction between the pawls and the force transfer element. Advantageously, the displacement of the component in one direction may be larger than in the opposite direction.
