An actuator device is described, apt at varying its functional condition from a state of rest to a working state, both stable, comprising a body (2,3) of contained dimensions, within which the following are housed:
actuating means, comprising a thermal actuator (5), an electric heater (6), electric contacting elements (7) and a transmission shaft (10,11) of the thrust generated by the actuator (5); means for maintaining the working state, also in absence of electrical supply to the actuating means, comprising bistable kinematic motion (20-30) of inclined planes and/or cams.