20130112104 | LINEAR ACTUATOR AND ROCKING CONTROLLER FOR RAILWAY VEHICLE - A compact linear actuator in which a back drive force is small and sticking due to abrasion powder and the like hardly occurs, and a rocking controller for a railway vehicle having the linear actuator are provided. The linear actuator has a main body of a hollow structure having an open end portion and a closed end portion, a cylinder that is fixed to a closed end portion side in the main body, and has an open end at an open end portion side, a linear motion rod that has one end portion extending from the open end portion of the main body, has a wear ring on an outer circumferential portion of the other end portion, and is housed in the cylinder slidably in an axial direction, and a hollow shaft rotatably supported in the main body, wherein the hollow shaft has a permanent magnet on a part of an outer circumferential surface, a winding section included on a part of an inner surface of the main body and the permanent magnet configure a hollow motor, a nut section coaxially fixed to the hollow shaft and a screw section on an outer circumferential surface of the linear motion rod are engaged with each other to configure a rotation/linear motion converting mechanism, and rotary oil seal sections that seal a gap between the hollow shaft and the main body in both sides in the axial direction relative to the nut section are included. | 05-09-2013 |