Patent attributes
A feed screw mechanism includes internally threaded member fixed within an output rod. The internally threaded member is threadedly engaged with an externally threaded member connected at axially one end in the direction of an axis thereof to a drive source, so that the output rod is moved in a direction of the axis relative to the externally threaded member by the relative rotation of the externally threaded member and the internally threaded member. The internally threaded member is coupled to the output rod at the axially other end in the direction of the axis by a threadedly coupling portion. Therefore, when pulling loads in directions away from each other are applied to the output rod and the externally threaded member, a compression load can be prevented from being applied from the output rod to the internally threaded member.
