ELECTRIC ACTUATOR DEVICE

PROBLEM TO BE SOLVED: To prevent intrusion of water or dust into a motor chamber or a gear chamber of an electric actuator device more certainly.SOLUTION: A breather passage that connects a motor chamber in an electric motor 37 of an actuator 26 with the atmosphere, is configured so that a plurality of breather chambers C1, C2, C3, and C4 are communicated by passages 31j and 32d with a smaller passage area than that of the breather chambers C1, C2, C3, and C4. Therefore, when a total volume of the breather passage is enlarged and a temperature of the actuator 26 is lowered, a flow rate of air drawn into actuator housings 31, 32, and 39 from exterior is reduced to enable to make water and dust less likely be drawn into the motor chamber. Further, a labyrinth structure of the breather passage is complicated to enable to make water and dust even more less likely be drawn into the motor chamber.