| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an expansion actuator having flexibility in an axial direction, capable of converting rotational motion of a motor and the like into an axial motion even when a shaft is bent, and being proper for a driving source of a service robot which stably operates.SOLUTION: The expansion actuator includes: rotational driving means; rotation-axial length converting means driven by the rotational driving means and changing an axial length; and restricting means which houses the rotation-axial length converting means, is joined to a housing of the rotational driving means and restricts deformation of the entire shape of the rotation-axial length converting means accompanying the rotation. The rotation-axial length converting means is composed of a fixed portion having a first member which is joined to the rotational driving means and rotationally driven, and a moving portion having a second member which is engaged with the first member and axially moves. At least one of the first member and the second member has the spiral shape in the axial direction, and the other member has the shape to be engaged therewith, and a rotational frequency or rotational driving force of the rotational driving means is not over a prescribed value.</p> |
