LINEAR ACTUATOR AND FORKLIFT

摘要

A linear actuator comprising: a screw shaft (1); a screw thread (30) helically formed on the outer periphery of the screw shaft; main rollers (4) each having a rolling surface (4c) for making contact with a flank surface (1a) of the screw thread and rolling on the flank surface through the rolling surface by rotating about the rotation axis (D) of the main roller; roller support members (6) for supporting the main rollers so that the main rollers can rotate about the rotation axes of thereof; and a roller cage (2) for supporting the roller support members so that the roller support members can rock against the force transmitted from the flank surface to the main rollers through the rolling surfaces, the roller cage (2) being adapted to rotate about the screw shaft relative thereto when the main rollers rolls. Even if there is play between parts due to dimensional errors thereof, the rollers and the screw shaft can be reliably caused to be in linear contact with each other.