An output shaft, to which the rotational force of a motor is transmitted, is rotatably supported and housed in a case. One end of the output shaft protrudes from the case, and a pinion gear is provided on this one end. Teeth that mesh with the pinion gear are provided on the outer circumferential surface of cables. A guide member for guiding the cables in such a way that they mesh with the pinion gear is mounted on the case. An urging plate portion that presses against the side of the pinion gear is provided on the guide member. The urging plate portion urges the output shaft in the axial direction and, as a result, rattle of the output shaft is alleviated.